Blocked polyisocyanate composition and use thereof

Abstract

A blocked polyisocyanate composition containing a blocked polyisocyanate obtained from a polyisocyanate and at least one blocking agent, wherein the blocking agent contains a compound represented by general formula (I) shown below, and the amount of methane tetracarbonyl structures represented by general formula (II) shown below, relative to the total molar amount within the blocked polyisocyanate of bonded structures in which the compound represented by general formula (I) is bonded to the polyisocyanate, is at least 0.5 mol % but not more than 10 mol %.

Claims

1. A blocked polyisocyanate composition comprising a blocked polyisocyanate obtained from a polyisocyanate and at least one blocking agent, wherein the blocking agent comprises a compound represented by general formula (I) shown below, and an amount of methane tetracarbonyl structures represented by general formula (II) shown below, relative to a total molar amount within the blocked polyisocyanate of bonded structures in which the compound represented by general formula (I) is bonded to the polyisocyanate, is at least 0.5 mol % but not more than 10 mol %: ##STR00029## wherein in general formula (I), R.sup.11 represents a hydroxyl group; an alkyl group which may contain at least one substituent selected from the group consisting of a hydroxyl group and an amino group; an amino group which may contain at least one substituent selected from the group consisting of a hydroxyl group and an alkyl group; an aryl group which may contain at least one substituent selected from the group consisting of a hydroxyl group and an amino group; or an alkoxy group which may contain at least one substituent selected from the group consisting of a hydroxyl group and an amino group, and in the amino group, two of the substituents may be linked together to form a ring, each of R.sup.12, R.sup.13 and R.sup.14 independently represents a hydrogen atom; a hydroxyl group; an alkyl group which may contain at least one substituent selected from the group consisting of a hydroxyl group and an amino group; an amino group which may contain at least one substituent selected from the group consisting of a hydroxyl group and an alkyl group; an aryl group which may contain at least one substituent selected from the group consisting of a hydroxyl group and an amino group; or an alkoxy group which may contain at least one substituent selected from the group consisting of a hydroxyl group and an amino group, and in the amino group, two of the substituents may be linked together to form a ring, but structures in which two or more of R.sup.12, R.sup.13 and R.sup.14 represent hydrogen atoms are excluded, ##STR00030## wherein in general formula (II), R.sup.21 represents a hydroxyl group; an alkyl group which may contain at least one substituent selected from the group consisting of a hydroxyl group and an amino group; an amino group which may contain at least one substituent selected from the group consisting of a hydroxyl group and an alkyl group; an aryl group which may contain at least one substituent selected from the group consisting of a hydroxyl group and an amino group; or an alkoxy group which may contain at least one substituent selected from the group consisting of a hydroxyl group and an amino group, and in the amino group, two of the substituents may be linked together to form a ring, each of R.sup.22, R.sup.23 and R.sup.24 independently represents a hydrogen atom; a hydroxyl group; an alkyl group which may contain at least one substituent selected from the group consisting of a hydroxyl group and an amino group; an amino group which may contain at least one substituent selected from the group consisting of a hydroxyl group and an alkyl group; an aryl group which may contain at least one substituent selected from the group consisting of a hydroxyl group and an amino group; or an alkoxy group which may contain at least one substituent selected from the group consisting of a hydroxyl group and an amino group, and in the amino group, two of the substituents may be linked together to form a ring, but structures in which two or more of R.sup.22, R.sup.23 and R.sup.24 represent hydrogen atoms are excluded, wherein a portion of, or all of, the blocked polyisocyanate comprises a structural unit derived from a hydrophilic compound, the hydrophilic compound comprises at least one group selected from the group consisting of nonionic hydrophilic groups and anionic hydrophilic groups, and an amount of the nonionic hydrophilic group relative to a solid fraction mass of the blocked polyisocyanate composition is 5.1% by mass or less.

2. The blocked polyisocyanate composition according to claim 1, wherein an amount of methane tetracarbonyl structures represented by general formula (II) shown above, relative to a total molar amount within the blocked polyisocyanate of bonded structures in which the compound represented by the general formula (I) is bonded to the polyisocyanate, is at least 0.5 mol % but not more than 8 mol %.

3. The blocked polyisocyanate composition according to claim 1, wherein an amount of methane tetracarbonyl structures represented by general formula (II) shown above, relative to a total molar amount within the blocked polyisocyanate of bonded structures in which the compound represented by the general formula (I) is bonded to the polyisocyanate, may be at least 0.5 mol % but not more than 6 mol %.

4. The blocked polyisocyanate composition according to claim 1, wherein each of R.sup.12, R.sup.13 and R.sup.14 independently represents a hydrogen atom; an alkyl group which may contain at least one substituent selected from the group consisting of a hydroxyl group and an amino group; or an aryl group which may contain at least one substituent selected from the group consisting of a hydroxyl group and an amino group; provided that structures in which two or more of R.sup.12, R.sup.13 and R.sup.14 represent hydrogen atoms are excluded.

5. The blocked polyisocyanate composition according to claim 1, wherein R.sup.11 represents an alkoxy group, R.sup.12 represents a hydrogen atom or an alkyl group, and R.sup.13 and R.sup.14 represent alkyl groups.

6. The blocked polyisocyanate composition according to claim 1, wherein an amount of the compound represented by the general formula (I), relative to a total molar amount of the blocking agent, is at least 80 mol % but not more than 100 mol %.

7. The blocked polyisocyanate composition according to claim 1, wherein the blocked polyisocyanate comprises a blocked isocyanurate trimer, and an amount of the blocked isocyanurate trimer, relative to a solid fraction amount of the blocked polyisocyanate composition, is at least 10% by mass.

8. The blocked polyisocyanate composition according to claim 1, wherein the blocked polyisocyanate contains an allophanate group and at least one functional group selected from the group consisting of an uretdione group, an iminooxadiazinedione group, an isocyanurate group, a urethane group and a biuret group, and if molar amounts of allophanate groups, uretdione groups, iminooxadiazinedione groups, isocyanurate groups, urethane groups and biurets groups are labelled a, b, c, d, e and f respectively, then a value of a/(a+b+c+d+e+f) is 0.05 or greater.

9. The blocked polyisocyanate composition according to claim 1, further comprising an active hydrogen group-containing compound.

10. The blocked polyisocyanate composition according to claim 9, wherein the active hydrogen group-containing compound comprises a monoalcohol.

11. The blocked polyisocyanate composition according to claim 10, wherein the monoalcohol is a secondary monoalcohol.

12. The blocked polyisocyanate composition according to claim 10, wherein the monoalcohol is 2-propanol or isobutyl alcohol.

13. The blocked polyisocyanate composition according to claim 9, wherein a molar amount of the active hydrogen group-containing compound, relative to a total molar amount of blocked isocyanate groups in the blocked polyisocyanate composition, is at least 10 mol % but not more than 1,000 mol %.

14. The blocked polyisocyanate composition according to claim 9, wherein a molar amount of the active hydrogen group-containing compound, relative to a total molar amount of blocked isocyanate groups in the blocked polyisocyanate composition, is at least 50 mol % but not more than 800 mol %.

15. The blocked polyisocyanate composition according to claim 1, wherein the polyisocyanate is a polyisocyanate obtained from at least one diisocyanate selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates.

16. The blocked polyisocyanate composition according to claim 15, wherein the diisocyanate comprises hexamethylene diisocyanate.

17. The blocked polyisocyanate composition according to claim 1, wherein an average number of isocyanate groups in the polyisocyanate is at least 3.3.

18. A coating material composition comprising the blocked polyisocyanate composition according to claim 1, and a polyhydric hydroxy compound.

19. A coating film obtained by curing the coating material composition according to claim 18.

20. A method for forming a coating film, comprising curing the coating material composition according to claim 18 by heating at a temperature of 80° C. or lower.

21. An article comprising a resin substrate having a melting point of not more than 120° C., and a coating film obtained by curing the coating material composition according to claim 18 on top of the resin substrate.

22. An adhesive composition comprising the blocked polyisocyanate composition according to claim 1.

23. An easy adhesion treated laminate comprising an adherend, and an easy adhesion treated layer obtained by applying the adhesive composition according to claim 22 to the adherend.

24. The easy adhesion treated laminate according to claim 23, wherein the adherend is a film or a plate.

25. A multilayer coating film laminate obtained by laminating a plurality of coating films to a substrate, wherein among the plurality of coating films, at least one coating film is obtained by curing a water-based coating material composition comprising the blocked polyisocyanate composition according to claim 1.

26. A method for forming a coating film, comprising forming a coating film by applying a water-based coating material composition comprising the blocked polyisocyanate composition according to claim 1 to a substrate.

27. The blocked polyisocyanate composition according to claim 9, wherein an average number of isocyanate groups in the polyisocyanate is at least 3.3.

28. The blocked polyisocyanate composition according to claim 1, wherein a lower limit of the amount of the nonionic hydrophilic group relative to the solid fraction mass of the blocked polyisocyanate composition is 1% by mass.

Description

EXAMPLES

(1) Embodiments of present invention are described below in further detail based on a series of examples and comparative examples, but the embodiments of the present invention are in no way limited by the following examples.

(2) The units “parts” used in the examples and comparative examples represents mass-referenced values. Further, “%” in the examples and comparative examples represents “% by mass”.

Examples 1-1 to 1-13, and Comparative Example 1-1

(3) <Test Items>

(4) The polyisocyanates obtained in the synthesis examples, the blocked polyisocyanate compositions produced in the examples and comparative example, the coating material compositions containing those blocked polyisocyanate compositions, and the coating films obtained from the coating material compositions were each subjected to measurement and evaluation of various physical properties in accordance with the methods described below.

(5) [Physical Property 1-1] Isocyanate Group (NCO) Content of Polyisocyanate

(6) First, 1 to 3 g of the polyisocyanate was weighed accurately into a conical flask (W g). Next, 20 mL of toluene was added, and the polyisocyanate was dissolved. Subsequently, 10 mL of a 2N toluene solution of di-n-butylamine was added, and following mixing, the mixture was left to stand for 15 minutes at room temperature. Next, 70 mL of isopropyl alcohol was added and mixed. The resulting liquid was then titrated with a 1N hydrochloric acid solution (factor F) using an indicator. The thus obtained titer was deemed V2 mL. Subsequently, the same operation was repeated without the polyisocyanate, and the obtained titer was deemed V1 mL. The formula (1) shown below was then used to calculate the isocyanate group (NCO) content of the polyisocyanate.
NCO content [% by mass]=(V1−V2)×F×42/(W×1000)×100  (1)
[Physical Property 1-2] Number Average Molecular Weight (Mn) of Polyisocyanate

(7) Using the polyisocyanate as a sample, the number average molecular weight (Mn) of the polyisocyanate was determined as the polystyrene-equivalent number average molecular weight by performing measurement by gel permeation chromatography (GPC) using the apparatus and conditions described below.

(8) (Measurement Conditions)

(9) Apparatus: HLC-802A (manufactured by Tosoh Corporation)

(10) Columns: 1×G1000HXL (manufactured by Tosoh Corporation), 1×G2000HXL (manufactured by Tosoh Corporation), and 1×G3000HXL (manufactured by Tosoh Corporation)

(11) Carrier: tetrahydrofuran

(12) Flow rate: 0.6 mL/minute

(13) Sample concentration: 1.0% by mass

(14) Injection volume: 20 μL

(15) Temperature: 40° C.

(16) Detection method: refractive index detector

(17) [Physical Property 1-3] Average Isocyanate Number of Polyisocyanate

(18) Using the polyisocyanate as a sample, the average isocyanate number was determined using formula (2) shown below.
Average isocyanate number=(number average molecular weight (Mn) of polyisocyanate×NCO content (% by mass): 0.01)/42  (2)
[Physical Property 1-4] Solid Fraction Amount of Blocked Polyisocyanate Composition

(19) The solid fraction amount of the blocked polyisocyanate composition was determined in the following manner.

(20) First, an aluminum dish with a base diameter of 38 mm was weighed accurately. About 1 g of the blocked polyisocyanate composition produced in the example or comparative example was then weighed accurately onto the aluminum dish (W1). Subsequently, the blocked polyisocyanate composition was adjusted to a uniform thickness. The blocked polyisocyanate composition mounted on the aluminum dish was then placed in a 105° C. oven for one hour. The aluminum dish was then returned to room temperature, and the blocked polyisocyanate composition remaining on the aluminum dish was weighed accurately (W2). The solid fraction amount (% by mass) of the blocked polyisocyanate composition was then calculated from formula (3) shown below.
Solid fraction amount of blocked polyisocyanate composition [% by mass]=W2/W1×100  (3)
[Physical Property 1-5] Effective Isocyanate Group (NCO) Content of Blocked Polyisocyanate Composition

(21) The effective isocyanate group (NCO) content of the blocked polyisocyanate composition was determined in the following manner.

(22) Here, the expression “effective isocyanate group (NCO) content” is a quantification of the amount of blocked isocyanate groups capable of participating in crosslinking reactions that exist within the blocked polyisocyanate composition following the blocking reaction, and is expressed as a % by mass value of the isocyanate groups.

(23) The effective NCO content was calculated using formula (4) shown below. In formula (4), the “NCO content of the polyisocyanate” and the “solid fraction amount of the blocked polyisocyanate composition” used the values calculated above for the physical property 1-1 and the physical property 1-4 respectively. In those cases where the sample was diluted with a solvent or the like, the effective NCO content value was calculated in the diluted state.
Effective NCO Content [% by mass]=[(solid fraction amount of blocked polyisocyanate composition [% by mass])×{(mass of polyisocyanate used in blocking reaction)×(NCO content of polyisocyanate [% by mass])}]/(mass of blocked polyisocyanate composition following blocking reaction)  (4)
[Physical Property 1-6] Amount of Isocyanurate Trimer Blocked with Three Molecules of Blocking Agent in Blocked Polyisocyanate Composition

(24) Using the blocked polyisocyanate composition as a sample, and using the same method as that described for the number average molecular weight of the polyisocyanate determined above in “physical property 1-2”, the blocked polyisocyanate composition was subjected to a GPC measurement. The obtained measurement results were then used to determine the ratio of the surface area for the isocyanurate trimer blocked with three molecules of the blocking agent relative to the surface area for the entire blocked polyisocyanate composition, and this ratio was deemed to represent the amount of the isocyanurate trimer blocked with three molecules of the blocking agent within the blocked polyisocyanate composition.

(25) [Physical Property 1-7] a/(a+b+c+d+e+f)

(26) Using a Biospin Avance 600 (product name) manufactured by Bruker Corporation, a .sup.13C-NMR measurement was conducted under the conditions listed below, and the molar amounts of allophanate groups, isocyanurate groups, uretdione groups, iminooxadiazinedione groups, urethane groups and biuret groups in the blocked isocyanate composition were each determined.

(27) (Measurement Conditions)

(28) .sup.13C-NMR apparatus: AVANCE 600 (manufactured by Bruker Corporation)

(29) CryoProbe CPDUL 600S3-C/H-D-05Z (manufactured by Bruker Corporation)

(30) Resonance frequency: 150 MHz

(31) Concentration: 60 wt/vol %

(32) Shift reference: CDCl.sub.3 (77 ppm)

(33) Accumulation number: 10,000

(34) Pulse program: zgpg 30 (proton perfect decoupling method, waiting time: 2 sec)

(35) Subsequently, based on the obtained measurement results, the following signal integral values were divided by the number of measured carbons, and the resulting values were used to determine the molar amount of each functional group.

(36) Uretdione group: integral value near 157 ppm÷2

(37) Iminooxadiazinedione group: integral value near 144 ppm÷1

(38) Isocyanurate group: integral value near 148 ppm÷3

(39) Allophanate group: integral value near 154 ppm÷1

(40) Urethane group: integral value near 156.5 ppm÷1−allophanate group integral value Biuret group: integral value near 156 ppm÷2

(41) Subsequently, the molar amounts determined for the allophanate groups, uretdione groups, iminooxadiazinedione groups, isocyanurate groups, urethane groups and biuret groups were labeled a, b, c, d, e and f respectively, and the ratio (a/a+b+c+d+e+f) of the molar amount of allophanate groups (a) relative to the total molar amount of allophanate groups, uretdione groups, iminooxadiazinedione groups, isocyanurate groups, urethane groups and biuret groups (a+b+c+d+e+f) was determined.

(42) [Physical Property 1-8] Amount of Methane Tetracarbonyl Structures in Blocked Polyisocyanate Composition

(43) The amount of methane tetracarbonyl structures relative to the total molar amount within the blocked polyisocyanate composition of polyisocyanates having the compound (I) bonded thereto was calculated using the method described below.

(44) Specifically, based on the results of an .sup.1H-NMR measurement performed using an Avance 600 (product name) manufactured by Bruker BioSpin Corporation, the ratio of the molar amount of methane tetracarbonyl structures relative to the total molar amount of methane tetracarbonyl structures, the keto forms of methane tricarbonyl structures and the enol forms of methane tricarbonyl structures (methane tetracarbonyl structures/(methane tetracarbonyl structures+methane tricarbonyl structure keto forms+methane tricarbonyl structure enol forms)) was determined, and this ratio was deemed the amount of methane tetracarbonyl structures. The measurement conditions were as follows.

(45) (Measurement Conditions)

(46) Apparatus: Avance 600 (product name) manufactured by Bruker BioSpin Corporation

(47) Solvent: deuterated chloroform

(48) Accumulation number: 256

(49) Sample concentration: 5.0% by mass

(50) Chemical shift reference: tetramethylsilane was deemed 0 ppm

(51) Further, the signal integral values described below were divided by the number of measured carbons, and the resulting values were used to determine the molar amounts of the various structures.

(52) NH protons of methane tetracarbonyl structure represented by general formula (II) shown below: near 8.0 ppm, integral value÷2

(53) ##STR00007##
(In general formula (II), R.sup.21, R.sup.22, R.sup.23 and R.sup.24 are the same as R.sup.11, R.sup.12, R.sup.13 and R.sup.14 respectively described above.)

(54) NH proton of keto form of methane tricarbonyl structure represented by general formula (III) shown below and enol form of methane tricarbonyl structure represented by general formula (IV) shown below: near 9.8 ppm, integral value÷1

(55) ##STR00008##
(In general formula (III), R.sup.31, R.sup.32, R.sup.33 and R.sup.34 are the same as R.sup.11, R.sup.12, R.sup.13 and R.sup.14 respectively described above.

(56) In general formula (IV), R.sup.41, R.sup.42, R.sup.43 and R.sup.44 are the same as R.sup.11, R.sup.12, R.sup.13 and R.sup.14 respectively described above.)

(57) NH proton of enol form of methane tricarbonyl structure represented by general formula (V) shown below: near 7.3 ppm integral value÷1

(58) ##STR00009##
(In general formula (V), R.sup.51, R.sup.52, R.sup.53 and R.sup.54 are the same as R.sup.11, R.sup.12, R.sup.13 and R.sup.14 respectively described above.)
[Evaluation 1-1] Viscosity Stability of Coating Material Composition

(59) An acrylic polyol (Setalux 1767 (product name) manufactured by Nuplex Resin Inc., resin fraction hydroxyl value: 150 mgKOH/g, resin fraction: 65%) was blended with each of the polyisocyanate compositions so as to achieve a ratio (isocyanate group/hydroxyl group) of the molar amount of isocyanate groups relative to the molar amount of hydroxyl groups of 0.8, and butyl acetate was then added to adjust the solid fraction to 40% by mass, thus obtaining a series of coating material compositions. Subsequently, 20 g of each of the thus obtained coating material compositions was subjected to an initial viscosity measurement, and then a measurement of the viscosity after storage in a 20 mL glass vial at 40° C. for 10 days (viscometer: RE-85R manufactured by Toki Sangyo Co., Ltd.). The change in the viscosity after storage relative to the initial viscosity was calculated, and the viscosity stability was evaluated against the following evaluation criteria.

(60) (Evaluation Criteria)

(61) OO: change in viscosity of less than ±30%

(62) O: change in viscosity of at least ±30% but less than ±50%

(63) Δ: change in viscosity of at least ±50%

(64) x: a solid formed

(65) [Evaluation 1-2] Low-Temperature Curability of Coating Film

(66) Various coating material compositions were prepared using the same method as that described for “evaluation 1-1”. Subsequently, each of the obtained coating material compositions was applied to a polypropylene plate in an amount sufficient to form a dried film thickness of 40 μm, and the applied composition was then heated and dried at 80° C. for 30 minutes, thus obtaining a cured coating film. The gel fraction of the obtained coating film was measured, and the low-temperature curability was evaluated against the following evaluation criteria. The gel fraction was determined by immersing the coating film in acetone at 23° C. for 24 hours, and was calculated as the value of the mass of the insoluble portion divided by the mass prior to immersion, expressed as a percentage (% by mass).

(67) (Evaluation Criteria)

(68) OO: gel fraction of at least 80% by mass

(69) O: gel fraction of at least 60% by mass but less than 80% by mass

(70) Δ: gel fraction of less than 60% by mass

(71) [Evaluation 1-3] Hardness Retention of Coating Film

(72) Various coating material compositions were prepared using the same method as that described for “evaluation 1-1”. Subsequently, 20 g of each of the obtained coating material compositions was stored in a 20 mL glass vial at 40° C. for 10 days. The initially prepared coating material composition and the coating material composition following storage were each applied to a glass plate in an amount sufficient to generate a dried film thickness of 40 μm, and then heated and dried at 100° C. for 30 minutes, thus obtaining a cured coating film. The Konig hardness of the obtained coating film was measured, the ratio of the hardness following storage relative to the initial hardness (hardness following storage/initial hardness) was calculated, and the coating film hardness retention was evaluated against the following evaluation criteria.

(73) (Evaluation Criteria)

(74) OO: hardness following storage/initial hardness of less than 1.2

(75) O: hardness following storage/initial hardness of at least 1.2 but less than 1.5

(76) Δ: hardness following storage/initial hardness of 1.5 or greater

(77) [Evaluation 1-4] Water Resistance of Coating Film

(78) Various coating material compositions were prepared using the same method as that described for “evaluation 1-1”. Subsequently, each of the obtained coating material compositions was applied to a glass plate in an amount sufficient to generate a dried film thickness of 40 μm, and was then heated and dried at 100° C. for 30 minutes, thus obtaining a cured coating film. The obtained coating film was immersed in water at 23° C., and after 24 hours, the external appearance of the coating film was inspected for the occurrence of coating film cloudiness or blistering, and the water resistance was evaluated against the following evaluation criteria.

(79) (Evaluation Criteria)

(80) OO: no occurrence of coating film cloudiness or blistering

(81) O: some minor occurrence of coating film cloudiness or blistering

(82) Δ: significant occurrence of coating film cloudiness or blistering

(83) [Evaluation 1-5] Coating Film Adhesion

(84) Various coating material compositions were prepared using the same method as that described for “evaluation 1-1”. Subsequently, each of the obtained coating material compositions was applied to a substrate formed from an ABS resin (melting point: 110° C.) in an amount sufficient to generate a dried film thickness of 40 μm, and the applied coating was then heated at 80° C. for 30 minutes in the case of the examples, or at 100° C. for 30 minutes in the case of the comparative example, thus forming a cured coating film. Using a cutting guide with a spacing interval of 2 mm, the obtained coating film was then cut to a depth that only penetrated through the coating film layer to form 100 grid squares. A cellophane adhesive tape (No. 405 manufactured by Nichiban Co., Ltd., width: 24 mm) was then affixed to the grid-shaped cut surface and rubbed with an eraser to ensure complete adhesion. Subsequently, the cellophane adhesive tape was pulled rapidly from the substrate formed from the ABS resin at a peel angle of 180°. The peeled surface was then inspected, the number of peeled grid squares was counted, and the coating film adhesion was evaluated against the following evaluation criteria.

(85) (Evaluation Criteria)

(86) OO: number of peeled grid squares was 0

(87) O: number of peeled grid squares was at least 1 but not more than 10

(88) Δ: number of peeled grid squares was at least 11 but not more than 31

(89) x: number of peeled grid squares was 31 or greater

(90) <Synthesis of Polyisocyanates>

[Synthesis Example 1-1] Synthesis of Polyisocyanate P1-1

(91) A four-neck flask fitted with a thermometer, a stirring blade and a reflux condenser was charged with 1,000 g of HDI and 33 g of trimethylolpropane under a stream of nitrogen, and the internal temperature of the flask was held at 70° C. while the contents were stirred. Tetramethylammonium hydroxide was then added to the flask, and when the yield reached 48%, phosphoric acid was added to halt the reaction. Following filtering of the reaction liquid, the unreacted HDI was removed using a thin-film distillation device, thus obtaining an isocyanurate polyisocyanate (hereafter sometimes referred to as the “polyisocyanate P1-1”).

(92) The NCO content of the obtained polyisocyanate P1-1 was 19.9% by mass, the number average molecular weight was 1,080, and the average isocyanate group number was 5.1.

[Synthesis Example 1-2] Synthesis of Polyisocyanate P1-2

(93) A four-neck flask fitted with a thermometer, a stirring blade and a reflux condenser was charged with 800 g of HDI, 200 g of IPDI and 75 g of trimethylolpropane under a stream of nitrogen, and the internal temperature of the flask was held at 70° C. while the contents were stirred. Tetramethylammonium hydroxide was then added to the flask, and when the yield reached 46%, phosphoric acid was added to halt the reaction. Following filtering of the reaction liquid, the unreacted HDI and IPDI were removed using a thin-film distillation device, thus obtaining an isocyanurate polyisocyanate (hereafter sometimes referred to as the “polyisocyanate P1-2”).

(94) The NCO content of the obtained polyisocyanate P1-2 was 18.5% by mass, the number average molecular weight was 1,200, and the average isocyanate group number was 5.3.

[Synthesis Example 1-3] Synthesis of Polyisocyanate P1-3

(95) A four-neck flask fitted with a thermometer, a stirring blade and a reflux condenser was charged with 1,000 g of HDI and 2 g of 2-ethylhexane-1,3-diol under a stream of nitrogen, and the internal temperature of the flask was held at 70° C. while the contents were stirred. Tetramethylammonium hydroxide was then added to the flask, and when the yield reached 40%, phosphoric acid was added to halt the reaction. Following filtering of the reaction liquid, the unreacted HDI was removed using a thin-film distillation device, thus obtaining an isocyanurate polyisocyanate (hereafter sometimes referred to as the “polyisocyanate P1-3”).

(96) The NCO content of the obtained polyisocyanate P1-3 was 21.8% by mass, the number average molecular weight was 655, and the average isocyanate group number was 3.4.

Production of Polyisocyanate Compositions

[Example 1-1] Production of Blocked Polyisocyanate Composition BL1-a1

(97) A four-neck flask fitted with a thermometer, a stirring blade and a reflux condenser was charged, under a stream of nitrogen, with 100 g of the polyisocyanate P1-1 obtained in Synthesis Example 1-1, 98 g of diisopropyl malonate and 117 g of dipropylene glycol dimethyl ether (DPDM), 0.9 parts of a methanol solution containing sodium methylate (28% by mass) was then added at room temperature, and a blocking reaction was conducted at 40° C. for 4 hours, thus obtaining a blocked polyisocyanate composition BL1-a1. The obtained blocked polyisocyanate composition BL1-a1 had a solid fraction of 60% by mass, an effective NCO content of 6.3% by mass, an amount of isocyanurate trimer of 14% by mass, a value for a/(a+b+c+d+e+f) of 0.28, and an amount of methane tetracarbonyl structures of 3.1 mol %. Using the methods described above, each of the various evaluations was performed. The results are shown below in Table 1.

[Examples 1-2 to 1-13, and Comparative Example 1-1] Production of Blocked Polyisocyanate Compositions BL1-a2 to BL1-a13 and BL1-b1

(98) With the exceptions of using the types and amounts of polyisocyanates and blocking agents and the amounts of solvent shown in Table 1, and adding 2-propanol following the blocking reaction at 40° C. for 4 hours and then stirring at 40° C. for one hour, the same method as that described for Example 1-1 was used to produce blocked polyisocyanate compositions BL1-a2 to BL1-a13 and BL1-b1.

(99) The compositions, physical properties and evaluation results for the obtained blocked isocyanate compositions BL1-a1 to BL1-a13 and BL1-b1 are shown below in Table 1. The types of blocking agents shown in Table 1 are as follows.

(100) (Blocking Agents)

(101) B1-1: diisopropyl malonate

(102) B1-2: di-sec-butyl malonate

(103) B1-3: di-tert-butyl malonate

(104) B1-4: tert-butylethyl malonate

(105) B1-5: isopropylethyl malonate

(106) B1-6: diethyl malonate

(107) B1-7: isopropyl acetoacetate

[Examples 1-14 and 1-15, and Comparative Examples 1-2 and 1-3] Production of Blocked Polyisocyanate Compositions BL1-a14 and BL1-a15, and BL1-b2 and BL1-b3

(108) With the exceptions of using the types and amounts of polyisocyanates and blocking agents, the amounts of solvent, the blocking reaction conditions, and the addition or otherwise of 2-propanol as shown in Table 1, the same method as that described for Example 1-1 was used to produce blocked polyisocyanate compositions BL1-a14 and BL1-a15, and BL1-b2 and BL1-b3.

(109) The compositions, physical properties and evaluation results for the obtained blocked isocyanate compositions BL1-a14 and BL1-a15, and BL1-b2 and BL1-b3 are shown below in Table 1. In the case of the hardness stability of the coating film from “evaluation 1-3” for the composition BL1-b3, solid matter developed in the coating material composition following storage, and therefore no evaluation was performed.

(110) TABLE-US-00001 TABLE 1 Example Example Example Example Example Example Example Example Example 1-1 1-2 1-3 1-4 1-5 1-6 1-7 1-8 1-9 Blocked polyisocyanate composition BL1-a1 BL1-a2 BL1-a3 BL1-a4 BL1-a5 BL1-a6 BL1-a7 BL1-a8 BL1-a9 Compo- Polyisocyanate P1-1 P1-1 P1-1 P1-1 P1-1 P1-1 P1-1 P1-2 P1-3 sition 100 g 100 g 100 g 100 g 100 g 100 g 100 g 100 g 100 g Blocking agent B1-1 B1-1 B1-2 B1-3 B1-4 B1-5 B1-1 B1-1 B1-1  98 g  98 g 113 g 113 g  98 g  91 g  49 g  91 g 107 g B-7  38 g Solvent: DPDM 117 g 117 g 124 g 124 g 117 g 113 g 111 g 113 g 122 g Alcohol: 2-propanol  0 g 158 g 169 g 169 g 158 g 152 g 149 g 153 g 165 g Reaction Temperature and time 40° C. 40° C. 40° C. 40° C. 40° C. 40° C. 40° C. 40° C. 40° C. conditions of blocking reaction 4 h 4 h 4 h 4 h 4 h 4 h 4 h 4 h 4 h Physical [Physical property 1-4] 60% 40% 40% 40% 40% 40% 40% 40% 40% properties Solid fraction amount [% by mass] [Physical property 1-5] 6.3%  4.2%  3.9%  3.9%  4.2%  4.4%  4.5%  4.0%  4.4%  Effective NCO content [% by mass] [Physical property 1-6] 14% 14% 14% 14% 14% 14% 14% 13% 55% Amount of isocyanurate trimer [% by mass] [Physical property 1-7] 0.28 0.28 0.28 0.28 0.28 0.28 0.26 0.31 0.10 a/(a + b + c + d + e + f) [Physical property 1-8] 3.1 3.1 3.5 3.5 3.3 3.5 2.8 3.0 3.5 Amount of methane tetracarbonyl structures [mol %] Evalua- [Evaluation 1-1] ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ tions Viscosity stability of coating material composition [Evaluation 1-2] ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Low-temperature curability of coating film [Evaluation 1-3] Hardness ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ retention of coating film [Evaluation 1-4] Water ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ resistance of coating film [Evaluation Coating 80° C. 1-5] film baking Adhesion temperature of Adhesion ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ coating of ABS film substrate and coating film Compara- Compara- Compara- tive tive tive Example Example Example Example Example Example Example Example Example 1-10 1-11 1-12 1-13 1-14 1-15 1-1 1-2 1-3 Blocked polyisocyanate composition BL1-a10 BL1-a11 BL1-a12 BL1-a13 BL1-a14 BL1-a15 BL-b1 BL-b2 BL-b3 Compo- Polyisocyanate P1-1 P1-1 P1-1 P1-1 P1-1 P1-1 P1-1 P1-1 P1-1 sition 100 g 100 g 100 g 100 g 100 g 100 g 100 g 100 g 100 g Blocking agent B1-1 B1-1 B1-1 B1-1 B1-1 B1-1 B1-6 B1-1 B1-1  98 g  98 g  98 g  98 g  98 g  98 g  83 g  98 g  98 g Solvent: DPDM 117 g 117 g 117 g 117 g 117 g 117 g 109 g 142 g 102 g Alcohol: 2-propanol 158 g 158 g 158 g 158 g 158 g  0 g 147 g 158 g  0 g Reaction Temperature and time of 40° C. 40° C. 40° C. 40° C. 30° C. 80° C. 40° C. 30° C. 80° C. conditions blocking reaction 4 h 4 h 4 h 4 h 8 h 1 h 4 h 8 h 1 h Physical [Physical property 1-4] 40% 40% 40% 40% 40% 60% 40% 38% 63% properties Solid fraction amount [% by mass] [Physical property 1-5] 4.2%  4.2%  4.2%  4.2%  4.2%  6.3%  4.6%  4.0%  6.6%  Effective NCO content [% by mass] [Physical property 1-6] 14% 14% 14% 14% 14% 14% 14% 14% 14% Amount of isocyanurate trimer [% by mass] [Physical property 1-7] 0.28 0.29 0.29 0.30 0.28 0.28 0.28 0.28 0.28 a/(a + b + c + d + e + f) [Physical property 1-8] 3.0 3.1 3.1 2.9 0.5 9.5 0.0 0.2 10.4 Amount of methane tetracarbonyl structures [mol %] Evalua- [Evaluation 1-1] ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Δ ○ ○ ○ ○ × tions Viscosity stability of coating material composition [Evaluation 1-2] ○ ○ ○ ○ ○ ○ ○ Δ ○ ○ ○ Low-temperature curability of coating film [Evaluation 1-3] Hardness ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ — retention of coating film [Evaluation 1-4] Water ○ ○ ○ ○ ○ ○ Δ Δ ○ resistance of coating film [Evaluation Coating 80° C. 100° C. 1-5] film baking Adhesion temperature of Adhesion ○ ○ ○ ○ ○ ○ Δ Δ Δ coating of ABS film substrate and coating film

(111) Table 1 reveals that for the blocked polyisocyanate compositions BL1-a1 to BL1-a15 containing a blocked polyisocyanate obtained from a polyisocyanate and the compound (I) (Examples 1-1 to 1-15), coating material compositions of excellent viscosity stability were able to be obtained. Further, by using these coating material compositions, coating films having excellent low-temperature curability, hardness retention and water resistance were able to be obtained. Furthermore, the coating films that used the blocked polyisocyanate compositions BL1-a1 to BL1-a15 (Examples 1-1 to 1-15) exhibited excellent adhesion to resin substrates.

(112) In contrast, for the blocked polyisocyanate composition BL1-b1 containing a blocked polyisocyanate that used a blocking agent other than the compound (I) (Comparative Example 1-1), and the blocked polyisocyanate compositions BL1-b2 and BL1-b3 in which the amount of methane tetracarbonyl structures was either less than 0.5 mol % or greater than 10 mol % (Comparative Examples 1-2 and 1-3), a combination of favorable viscosity stability when used as a coating material composition and favorable low-temperature curability, hardness retention and water resistance when used as a coating film could not be achieved. Further, the coating films that used the blocked polyisocyanate compositions BL1-b1 to BL1-b3 (Comparative Examples 1-1 to 1-3) exhibited inferior adhesion to resin substrates.

(113) Further, in the blocked polyisocyanate compositions BL1-a2 to BL1-a14 containing added 2-propanol (Examples 1-2 to 1-14), the viscosity stability when used as a coating material was particularly favorable compare with that obtained for the blocked polyisocyanate compositions BL1-a1 and BL1-a15 that did not contain 2-propanol (Examples 1-1 and 1-15).

(114) Further, in the blocked polyisocyanate compositions BL1-a4 and BL1-a5 that used either B1-3 (di-tert-butyl malonate) or B1-4 (tert-butylethyl malonate) as the blocking agent (Examples 1-4 and 1-5), the low-temperature curability and water resistance and the like when used as a coating film were more favorable than those obtained for the blocked polyisocyanate compositions BL1-a1 to BL1-a3 and BL1-a6 to BL1-a15 that used other blocking agents (Examples 1-1 to 1-3 and 1-6 to 1-15).

(115) Furthermore, in the blocked polyisocyanate compositions BL1-a1 to BL1-a3 and BL1-a7 to BL1-a15 that used either B1-1 (diisopropyl malonate) or B1-2 (di-sec-butyl malonate) as the blocking agent (Examples 1-1 to 1-3 and 1-7 to 1-15), the hardness retention when used as a coating film was particularly favorable compared with that obtained for the blocked polyisocyanate compositions BL1-a4 and BL1-a6 that used other blocking agents (Examples 1-4 to 1-6).

Examples 2-1 to 2-13 and Comparative Examples 2-1 and 2-2

(116) <Test Items>

(117) The blocked polyisocyanate compositions produced in the examples and comparative examples, the one-component coating material compositions containing those blocked polyisocyanate compositions, and the coating films obtained from the one-component coating material compositions were each subjected to measurement and evaluation of various physical properties in accordance with the methods described below.

(118) [Physical Property 2-1] NCO Content of Polyisocyanate

(119) First, 1 to 3 g of the polyisocyanate was weighed accurately into a conical flask (W g). Next, 20 mL of toluene was added, and the polyisocyanate was dissolved. Subsequently, 10 mL of a 2N toluene solution of di-n-butylamine was added, and following mixing, the mixture was left to stand for 15 minutes at room temperature. Next, 70 mL of isopropyl alcohol was added and mixed. The resulting liquid was then titrated with a 1N hydrochloric acid solution (factor F) using an indicator. The thus obtained titer was deemed V2 mL. Subsequently, the same operation was repeated without the polyisocyanate, and the obtained titer was deemed V mL. The formula (1) shown below was then used to calculate the NCO content of the polyisocyanate.
NCO content [% by mass]=(V1−V2)×F×42/(W×1000)×100  (1)
[Physical Property 2-2] Non-Volatile Fraction (Solid Fraction Amount) of Blocked Polyisocyanate Composition

(120) The non-volatile fraction (solid fraction amount) of the blocked polyisocyanate composition was determined in the following manner.

(121) First, an aluminum dish with a base diameter of 38 mm was weighed accurately. About 1 g of the blocked polyisocyanate composition produced in the example or comparative example was then weighed accurately onto the aluminum dish (W1). Subsequently, the blocked polyisocyanate composition was adjusted to a uniform thickness. The blocked polyisocyanate composition mounted on the aluminum dish was then placed in a 105° C. oven for one hour. The aluminum dish was then returned to room temperature, and the blocked polyisocyanate composition remaining on the aluminum dish was weighed accurately (W2). The non-volatile fraction (solid fraction amount) of the blocked polyisocyanate composition was then calculated from formula (3) shown below.
Solid fraction amount of blocked polyisocyanate composition [% by mass]=W2/W1×100  (3)
[Physical Property 2-3] Effective NCO Content

(122) The effective NCO content of each of the blocked polyisocyanate compositions produced in the examples and comparative examples was determined in the following manner.

(123) Here, the expression “effective NCO content” is a quantification of the amount of blocked isocyanate groups capable of participating in crosslinking reactions that exist within the blocked polyisocyanate composition following the blocking reaction, and is expressed as a % by mass value of the isocyanate groups.

(124) The effective NCO content was calculated using formula (4) shown below. In formula (4), the “NCO content of the polyisocyanate” and the “non-volatile fraction of the blocked polyisocyanate composition” used the values calculated above for the physical property 2-1 and the physical property 2-2 respectively. In those cases where the sample was diluted with a solvent or the like, the effective NCO content value was calculated in the diluted state.
Effective NCO Content [% by mass]=[(solid fraction amount of blocked polyisocyanate composition [% by mass])×{(mass of polyisocyanate used in blocking reaction)×(NCO content of polyisocyanate [% by mass])}]/(mass of blocked polyisocyanate composition following blocking reaction)  (4)
[Physical Property 2-4] Amount of Methane Tetracarbonyl Structures

(125) The amount of methane tetracarbonyl structures relative to the total molar amount within the blocked polyisocyanate of polyisocyanates having a compound represented by general formula (I-1) shown below (hereafter sometimes referred to as the “compound (I-1)”) bonded thereto was calculated using the method described below.

(126) ##STR00010##
(In general formula (I-1), R.sup.111 represents a methyl group, diethylamino group, ethoxy group, or 1,1-dimethylethoxy group.)

(127) Specifically, based on the results of an .sup.1H-NMR measurement performed using an Avance 600 (product name) manufactured by Bruker BioSpin Corporation, the molar ratio of methane tetracarbonyl structures/(methane tetracarbonyl structures+methane tricarbonyl structure keto forms+methane tricarbonyl structure enol forms) was determined, and this molar ratio was deemed the amount of methane tetracarbonyl structures. The measurement conditions were as follows.

(128) (Measurement Conditions)

(129) Apparatus: Avance 600 (product name) manufactured by Bruker BioSpin Corporation

(130) Solvent: deuterated chloroform

(131) Accumulation number: 256

(132) Sample concentration: 5.0% by mass

(133) Chemical shift reference: tetramethylsilane was deemed 0 ppm

(134) Further, the signal integral values described below were divided by the number of measured carbons, and the resulting values were used to determine the various molar ratios.

(135) NH proton of keto form of methane tetracarbonyl structure represented by general formula (III-1) shown below: near 7.3 ppm, integral value÷1

(136) ##STR00011##
(In general formula (III-1), R.sup.311 is the same as R.sup.111 described above.)

(137) NH proton of enol form of methane tricarbonyl structure represented by general formula (IV-1) shown below and enol form of methane tricarbonyl structure represented by general formula (V-1) shown below: near 9.8 ppm, integral value÷1

(138) ##STR00012##
(In general formulas (IV-1) and (V-1), R.sup.411 and R.sup.511 are each the same as R.sup.111 described above.)

(139) NH protons of methane tetracarbonyl structure represented by general formula (II-1) shown below: near 8.0 ppm integral value 2

(140) ##STR00013##
(In general formula (II-1), R.sup.211 is the same as R.sup.111 described above.)
[Evaluation 2-1] Low-Temperature Curability Evaluation

(141) The low-temperature curability of the coating films produced in the examples and comparative examples was evaluated by measuring the gel fraction in the manner described below. A higher value for the gel fraction can be deemed to indicate superior low-temperature curability.

(142) Each of the coating films produced in the examples and comparative examples was immersed in acetone at 20° C. for 24 hours. The gel fraction [% by mass] was then determined as the value of the mass of the insoluble portion divided by the mass prior to immersion.

(143) [Evaluation 2-2] Storage Stability Evaluation

(144) The storage stability of the one-component coating material compositions produced in the examples and comparative examples was evaluated using the method described below.

(145) The viscosity of a 20 g sample of the one-component coating material composition that had been stored in a 20 mL glass vial at 40° C. for one day was measured (viscometer: RE-85R manufactured by Toki Sangyo Co., Ltd.). Based on the measurement result, the storage stability was evaluated against the following evaluation criteria.

(146) (Evaluation Criteria)

(147) O: increase of not more than 1.5-fold relative to initial viscosity

(148) Δ: increase of 1.5-fold or greater relative to initial viscosity

(149) x: sample gelled

[Synthesis Example 2-1] Synthesis of Isocyanurate Polyisocyanate

(150) A four-neck flask fitted with a thermometer, a stirring blade and a reflux condenser was charged with 1,000 parts of HDI, and the internal temperature of the flask was held at 70° C. while the contents were stirred. Tetramethylammonium caprate was then added to the flask, and when the yield reached 40%, phosphoric acid was added to halt the reaction. Following filtering of the reaction liquid, the unreacted HDI was removed using a thin-film distillation device, thus obtaining an isocyanurate polyisocyanate (hereafter referred to as the “polyisocyanate P2-1”).

(151) The NCO content of the obtained polyisocyanate P2-1 was 21.8% by mass.

Example 2-1

(152) (1) Production of Blocked Polyisocyanate Composition BL2-1a

(153) A four-neck flask fitted with a thermometer, a stirring blade and a reflux condenser was charged, under a stream of nitrogen and at room temperature, with 100 parts of P2-1 obtained in Synthesis Example 2-1, 112 parts of di-tert-butyl malonate (100 mol % equivalence relative to the isocyanate (NCO) groups), 141 parts of butyl acetate, and 0.9 parts of a methanol solution containing sodium methylate (28% by mass) (equivalent to 0.252 parts of sodium methylate), and a blocking reaction was conducted at 40° C. for 4 hours, thus obtaining a blocked polyisocyanate composition BL2-1a. The obtained blocked polyisocyanate composition BL2-1a had an effective NCO content of 6.2% by mass and a non-volatile fraction of 60% by mass.

(154) (2) Production of One-Component Coating Material Composition T2-1a

(155) Subsequently, the blocked polyisocyanate composition BL2-1a obtained above in (1) and an acrylic polyol (Setalux 1767 (product name) manufactured by Nuplex Resin Inc., resin fraction hydroxyl value: 150 mgKOH/g, resin fraction: 65%) were blended so as to achieve equivalence between the blocked NCO groups and the hydroxyl groups of the acrylic polyol. Butyl acetate was then added to obtain a one-component coating material composition T2-1a with a total resin fraction of 45%.

(156) (3) Production of Coating Films

(157) Subsequently, the one-component coating material composition T2-1a obtained above in (2) was applied in an amount sufficient to form a dried film thickness of 30 μm Samples of the films were baked for 30 minutes in a drying oven held at 70° C., 80° C. or 90° C. to obtain a series of coating films.

(158) Each of the obtained coating films was evaluated for low-temperature curability (gel fraction) in accordance with the evaluation method described above. The results revealed a gel fraction of 76% by mass for the coating film baked at 70° C., a gel fraction of 86% by mass for the coating film baked at 80° C., and a gel fraction of 90% by mass for the coating film baked at 90° C. These results are also shown below in Table 2.

Examples 2-2 to 2-8, 2-10 and 2-11, and Comparative Examples 2-2 and 2-3

(159) (1) Production of Blocked Polyisocyanate Compositions BL2-2a to BL2-8a, BL2-10a and BL2-11a, and BL2-2b and BL2-3b

(160) With the exceptions of altering the types and masses of polyisocyanates and blocking agents and the blocking reaction conditions as shown in Table 2, the same method as that described for (1) of Example 2-1 was used to produce blocked polyisocyanate compositions BL2-2a to BL2-8a, BL2-10a and BL2-11a, and BL2-2b and BL2-3b. The effective NCO content and the non-volatile fraction for each of the obtained blocked isocyanate compositions are shown below in Table 2. The blocking agent used in Example 2-4 was a compound represented by formula (VI) shown below.

(161) ##STR00014##
(2) Production of One-Component Coating Material Compositions T2-2a to T2-8a, T2-10a and T2-11a, and T2-2b and T2-3b

(162) Subsequently, using the blocked isocyanate compositions obtained above in (1), the same method as that described for (2) of Example 2-1 was used to produce one-component coating material compositions T2-2a to T2-8a, T2-10a and T2-11a, and T2-2b and T2-3b.

(163) (3) Production of Coating Films

(164) Subsequently, for each of the one-component coating material compositions obtained above in (2), the same method as that described for (3) of Example 2-1 was used to produce coating films. Each of the obtained coating films was evaluated for low-temperature curability (gel fraction) in accordance with the evaluation method described above. The results are shown below in Table 2.

Examples 2-9 and 2-12 to 2-14, and Comparative Examples 2-1 and 2-4

(165) (1) Production of Blocked Polyisocyanate Compositions BL2-9a, BL2-12a to BL2-14a, and BL2-1b and BL2-4b

(166) With the exceptions of altering the types and masses of polyisocyanates and blocking agents and the reaction conditions as shown in Table 2, the same method as that described for (1) of Example 2-1 was used to conduct blocking reactions. Subsequently, a solvent 2 (n-butanol or isobutanol) was added to the product of the blocking reaction in a mass shown in Table 2, and the mixture was mixed at 80° C. for one hour to obtain blocked polyisocyanate compositions BL2-9a, BL2-12a to BL2-14a, and BL2-1b and BL2-4b. The effective NCO content and the non-volatile fraction for each of the obtained blocked isocyanate compositions are shown below in Table 2.

(167) (2) Production of One-Component Coating Material Compositions T2-9a. T2-12a to T2-14a, and T2-1b and T2-4b

(168) Subsequently, using the blocked isocyanate compositions obtained above in (1), the same method as that described for (2) of Example 2-1 was used to produce one-component coating material compositions T2-9a, T2-12a to T2-14a, and T2-1b and T2-4b.

(169) (3) Production of Coating Films

(170) Subsequently, for each of the one-component coating material compositions obtained above in (2), the same method as that described for (3) of Example 2-1 was used to produce coating films. Each of the obtained coating films was evaluated for low-temperature curability (gel fraction) in accordance with the evaluation method described above. The results are shown below in Table 2.

(171) TABLE-US-00002 TABLE 2 Example Example Example Example Example Example Example Example Example 2-1 2-2 2-3 2-4 2-5 2-6 2-7 2-8 2-9 Blocking Polyisocyanate P2-1 P2-1 P2-1 P2-1 P2-1 P2-1 P2-1 P2-1 P2-1 100 parts 100 parts 100 parts 100 parts 100 parts 100 parts 100 parts 100 parts 100 parts Blocking di-t-butyl 112 parts  56 parts  8 parts  45 parts  67 parts  22 parts agent malonate t-butylethyl  98 parts  78 parts malonate t-butyl  82 parts  41 parts acetoacetate Compound 141 parts represented by formula (VI) Diethyl  63 parts  40 parts  27 parts malonate Ethyl acetoacetate 28% sodium  0.9 parts  0.8 parts  0.8 parts  1.0 parts  0.8 parts  0.7 parts  0.8 parts  0.8 parts  0.8 parts methylate solution Solvent 1 Butyl acetate 141 parts 131 parts 121 parts 160 parts 131 parts 113 parts 123 parts 129 parts 50 parts Blocking Temperature, 40° C. 40° C. 40° C. 40° C. 40° C. 40° C. 40° C. 40° C. 80° C. reaction time 4 h 4 h 4 h 4 h 4 h 4 h 4 h 4 h 3 h Mixing Solvent 2 n-butanol conditions Isobutanol 84 parts Mixing Temperature, 80° C. time 1 h Physical Effective NCO content 6.2% 6.6% 7.2% 5.4% 6.6% 7.7% 7.0% 6.7% 6.5% properties Non-volatile fraction  60%  60%  60%  60%  60%  60%  60%  60%  60% Methane tetracarbonyl 4.8% 5.3% 2.8% 3.5% 4.2% 2.7% 4.1% 4.6% 6.8% fraction Evaluation Gel fraction 70° C.  76%  74%  70%  72%  72%  30%  51%  62%  70% results 80° C.  86%  85%  78%  80%  81%  65%  68%  70%  77% 90° C.  90%  91%  88%  89%  88%  87%  89%  90%  88% Storage stability × × × × × × × × × Compar- Compar- Compar- Compar- ative ative ative ative Example Example Example Example Example Example Example Example Example 2-10 2-11 2-12 2-13 2-14 2-1 2-2 2-3 2-4 Blocking Polyisocyanate P2-1 P2-1 P2-1 P2-1 P2-1 P2-1 P2-1 P2-1 P2-1 100 parts 100 parts 100 parts 100 parts 100 parts 100 parts 100 parts 100 parts 100 parts Blocking di-t-butyl 112 parts 112 parts 112 parts 112 parts 112 parts 112 parts 112 parts agent malonate t-butylethyl malonate t-butyl acetoacetate Compound represented by formula (VI) Diethyl  61 parts  83 parts malonate Ethyl  21 parts acetoacetate 28% sodium  0.9 parts  0.9 parts  0.9 parts  0.9 parts  0.9 parts  0.8 parts  0.8 parts  0.9 parts  0.9 parts methylate solution Solvent 1 Butyl acetate 318 parts 318 parts  52 parts 141 parts 141 parts  45 parts 122 parts 346 parts  37 parts Blocking Temperature, 30° C. 40° C. 80° C. 40° C. 40° C. 80° C. 40° C. 30° C. 80° C. reaction time 8 h 4 h 3 h 4 h 4 h 3 h 4 h 8 h 3 h Mixing Solvent 2 n-butanol 177 parts  76 parts conditions Isobutanol  88 parts 177 parts  88 parts Mixing Temperature, 80° C. 40° C. 40° C. 80° C. 80° C. time 1 h 2 h 2 h 1 h 1 h Physical Effective NCO content 4.1% 4.1% 6.2% 4.1% 4.1% 7.5% 7.1% 3.9% 6.5% properties Non-volatile fraction  40%  40%  60%  40%  40%  60%  60%  38%  63% Methane tetracarbonyl 0.5% 1.2% 9.8% 5.1% 4.7% 0.0% 0.0% 0.3% 10.3%  fraction Evaluation Gel 70° C.  75%  76%  75%  68%  72%  0%   0%  76%  76% results fraction 80° C.  83%  85%  82%  76%  80%  51%  25%  85%  83% 90° C.  90%  90%  92%  87%  88%  80%  76%  90%  91% Storage stability Δ Δ ○ ○ ○ ○ × × Δ

(172) The coating films produced using the blocked polyisocyanate compositions BL2-1a to BL2-14a obtained from the polyisocyanate P2-1 and a compound represented by general formula (I-1) shown above (Examples 2-1 to 2-14) exhibited excellent low-temperature curability, with a gel fraction of at least 87% by mass at a curing temperature of 90° C., a gel fraction of at least 65% by mass at a curing temperature of 80° C., and a gel fraction of at least 30% by mass at a curing temperature of 70° C. Further, the blocked polyisocyanate compositions BL2-12a to BL2-14a which used only di-tert-butyl malonate as the blocking agent, and also contained n-butanol or isobutanol (Examples 2-12 to 2-14) also exhibited particularly superior storage stability.

(173) In contrast, the coating films produced using the blocked polyisocyanate compositions BL2-1b and BL2-2b obtained from the polyisocyanate P2-1 and at least one compound selected from the group consisting of diethyl malonate and ethyl acetoacetate (Comparative Examples 2-1 and 2-2) had inferior low-temperature curability, with a gel fraction of at least 75% by mass at a curing temperature of 90° C., a gel fraction of at least 25% by mass at a curing temperature of 80° C., and a gel fraction of at least 0% by mass at a curing temperature of 70° C.

(174) Further, the coating films produced using the blocked polyisocyanate compositions BL2-3b and BL2-4b having an amount of methane tetracarbonyl structures (a methane tetracarbonyl fraction) of less than 0.5 mol % or greater than 10.0 mol % (Comparative Examples 2-3 and 2-4) exhibited excellent low-temperature curability but had poor storage stability.

(175) The above results confirmed that the blocked polyisocyanate composition of an embodiment of the present invention was able to produce a coating film having excellent low-temperature curability.

Examples 3-1 to 3-12, and Comparative Examples 3-1 and 3-2

(176) <Test Items>

(177) The blocked polyisocyanate compositions produced in the examples and comparative examples, the coating material compositions containing those blocked polyisocyanate compositions, and the coating films obtained from the coating material compositions were each subjected to measurement and evaluation of various physical properties in accordance with the methods described below.

(178) [Physical Property 3-1] NCO Content of Polyisocyanate

(179) First, 1 to 3 g of the polyisocyanate was weighed accurately into a conical flask (W g). Next, 20 mL of toluene was added, and the polyisocyanate was dissolved. Subsequently, 10 mL of a 2N toluene solution of di-n-butylamine was added, and following mixing, the mixture was left to stand for 15 minutes at room temperature. Next, 70 mL of isopropyl alcohol was added and mixed. The resulting liquid was then titrated with a 1N hydrochloric acid solution (factor F) using an indicator. The thus obtained titer was deemed V2 mL. Subsequently, the same operation was repeated without the polyisocyanate, and the obtained titer was deemed V1 mL. The formula (1) shown below was then used to calculate the NCO content of the polyisocyanate.
NCO content [% by mass]=(V1−V2)×F×42(W×1000)×100  (1)
[Physical Property 3-2] Non-Volatile Fraction (Solid Fraction Amount) of Blocked Polyisocyanate Composition

(180) The non-volatile fraction of the blocked polyisocyanate composition was determined in the following manner.

(181) First, an aluminum dish with a base diameter of 38 mm was weighed accurately. About 1 g of the blocked polyisocyanate composition produced in the example or comparative example was then weighed accurately onto the aluminum dish (W1). Subsequently, the blocked polyisocyanate composition was adjusted to a uniform thickness. The blocked polyisocyanate composition mounted on the aluminum dish was then placed in a 105° C. oven for one hour. The aluminum dish was then returned to room temperature, and the blocked polyisocyanate composition remaining on the aluminum dish was weighed accurately (W2). The non-volatile fraction (solid fraction amount) of the blocked polyisocyanate composition was then calculated from formula (3) shown below.
Solid fraction amount of blocked polyisocyanate composition [% by mass]=W2/W1*100  (3)
[Physical Property 3-3] Effective NCO Content

(182) The effective NCO content of each of the blocked polyisocyanate compositions produced in the examples and comparative examples was determined in the following manner.

(183) Here, the expression “effective NCO content” is a quantification of the amount of blocked isocyanate groups capable of participating in crosslinking reactions that exist within the blocked polyisocyanate composition following the blocking reaction, and is expressed as a % by mass value of the isocyanate groups.

(184) The effective NCO content was calculated using formula (4) shown below. In formula (4) below, the “NCO content of the polyisocyanate” and the “non-volatile fraction of the blocked polyisocyanate composition” used the values calculated above for the physical property 3-1 and the physical property 3-2 respectively. In those cases where the sample was diluted with a solvent or the like, the effective NCO content value was calculated in the diluted state.
Effective NCO Content [% by mass]=[(solid fraction amount of blocked polyisocyanate composition [% by mass])×{(mass of polyisocyanate used in blocking reaction)×(NCO content of polyisocyanate [% by mass])}]/(mass of blocked polyisocyanate composition following blocking reaction)  (4)
[Physical Property 3-4] Amount of Methane Tetracarbonyl Structures

(185) The amount of methane tetracarbonyl structures represented by general formula (II-2) shown below relative to the total molar amount within the blocked polyisocyanate composition of polyisocyanates having a compound represented by general formula (I-2) shown below (hereafter sometimes referred to as the “compound (I-2)”) bonded thereto was calculated using the method described below.

(186) ##STR00015##
(In general formula (I-2), R.sup.121 represents an ethoxy group or a 1,1-dimethylethoxy group.)

(187) ##STR00016##
(In general formula (11-2), R.sup.221 is the same as R.sup.121 described above.)

(188) Specifically, based on the results of an .sup.1H-NMR measurement performed using an Avance 600 (product name) manufactured by Bruker BioSpin Corporation, the molar ratio of methane tetracarbonyl structures/(methane tetracarbonyl structures+methane tricarbonyl structure keto forms+methane tricarbonyl structure enol forms) was determined, and this molar ratio was deemed the amount of methane tetracarbonyl structures. The measurement conditions were as follows.

(189) (Measurement Conditions)

(190) Apparatus: Avance 600 (product name) manufactured by Bruker BioSpin Corporation

(191) Solvent: deuterated chloroform

(192) Accumulation number: 256

(193) Sample concentration: 5.0% by mass

(194) Chemical shift reference: tetramethylsilane was deemed 0 ppm

(195) Further, the signal integral values described below were divided by the number of measured carbons, and the resulting values were used to determine the various molar ratios.

(196) NH proton of keto form of methane tetracarbonyl structure represented by general formula (III-2) shown below: near 7.3 ppm, integral value÷1

(197) ##STR00017##
(In general formula (III-2), R.sup.321 is the same as R.sup.121 described above.)

(198) NH proton of enol form of methane tricarbonyl structure represented by general formula (IV-2) shown below and enol form of methane tricarbonyl structure represented by general formula (V-2) shown below: near 9.8 ppm, integral value÷1

(199) ##STR00018##
(In general formulas (IV-2) and (V-2), R.sup.421 and R.sup.521 are each the same as R.sup.121 described above.)

(200) NH protons of methane tetracarbonyl structure represented by general formula (II-2) shown below: near 8.0 ppm, integral value÷2

(201) ##STR00019##
(In general formula (II-2), R.sup.221 is the same as R.sup.121 described above.)
[Evaluation 3-1] Low-Temperature Curability Evaluation

(202) The low-temperature curability of the coating films produced in the examples and comparative examples was evaluated by measuring the gel fraction in the manner described below. A higher value for the gel fraction can be deemed to indicate superior low-temperature curability.

(203) Each of the coating films from the examples and comparative examples was immersed in acetone at 20° C. for 24 hours. The gel fraction [% by mass] was then determined as the value of the mass of the insoluble portion divided by the mass prior to immersion.

(204) [Evaluation 3-2] Storage Stability Evaluation

(205) The storage stability of the coating material compositions produced in the examples and comparative examples was evaluated using the method described below.

(206) The viscosity of a 20 g sample of the coating material composition that had been stored in a glass vial at 40° C. for 10 days was measured (viscometer: RE-85R manufactured by Toki Sangyo Co., Ltd.). Based on the measurement result, the storage stability was evaluated against the following evaluation criteria.

(207) (Evaluation Criteria)

(208) O: increase of less than 3.0-fold relative to initial viscosity

(209) Δ: increase of 3.0-fold or greater relative to initial viscosity

(210) x: sample gelled

[Synthesis Example 3-1] Synthesis of Isocyanurate Polyisocyanate

(211) A four-neck flask fitted with a thermometer, a stirring blade and a reflux condenser was charged with 1,000 parts of HDI under a stream of nitrogen, and the internal temperature of the flask was held at 70° C. while the contents were stirred. Tetramethylammonium caprate was then added to the flask, and when the yield reached 40%, phosphoric acid was added to halt the reaction. Following filtering of the reaction liquid, the unreacted HDI was removed using a thin-film distillation device, thus obtaining an isocyanurate polyisocyanate (hereafter referred to as the “polyisocyanate P3-1”). The NCO content of the obtained polyisocyanate P3-1 was 21.8% by mass.

Examples 3-1 to 3-4

(212) (1) Production of Blocked Polyisocyanate Compositions BL3-1a to BL3-4a

(213) Into a four-neck flask fitted with a thermometer, a stirring blade and a reflux condenser were weighed, under a stream of nitrogen, P3-1 obtained in Synthesis Example 3-1, di-tert-butyl malonate (100 mol % equivalence relative to the isocyanate (NCO) groups) or tert-butylethyl malonate (100 mol % equivalence relative to the isocyanate (NCO) groups) and butyl acetate, and the resulting mixture was stirred at room temperature for several minutes until a uniform mixture was obtained. Subsequently, a methanol solution containing sodium methylate (28% by mass) (equivalent to 0.252 parts of sodium methylate) was added at room temperature, the temperature was raised to either 40° C. or 80° C., and a blocking reaction was conducted for 4 hours. The amounts used of the various components are shown in Table 3. Next, a solvent 2 (n-butanol, isobutanol or 2-propanol) was added in a mass shown in Table 3, as an active hydrogen group-containing compound, to the product of the blocking reaction, and the mixture was mixed at 40° C. for one hour, thus obtaining a series of blocked polyisocyanate compositions BL3-1a to BL3-4a. The effective NCO content and the non-volatile fraction of each of the obtained blocked polyisocyanate compositions BL3-1a to BL3-4a are shown in Table 3.

(214) (2) Production of Coating Material Compositions T3-1a to T3-4a (Blending Method 1)

(215) First, an acrylic polyol (Setalux 1767 (product name) manufactured by Nuplex Resin Inc., resin fraction hydroxyl value: 150 mgKOH/g, resin fraction: 65%) was diluted with butyl acetate. Subsequently, with each of the blocked polyisocyanate compositions BL3-1a to BL3-4a obtained above in (1) undergoing constant stirring, the acrylic polyol was added gradually to obtain coating material compositions T3-1a to T3-4a with a total resin fraction of 45%. The blend amounts were adjusted to achieve equivalence between the blocked NCO groups of the blocked polyisocyanate compositions BL3-1a to BL3-4a and the hydroxyl groups of the acrylic polyol. The storage stability of the obtained coating material compositions was evaluated in accordance with the evaluation method described above. The results are shown below in Table 3.

(216) (3) Production of Coating Films

(217) Subsequently, the coating material compositions T3-1a to T3-4a obtained above in (2) were each applied in an amount sufficient to form a dried film thickness of 30 μm. Subsequently, samples of the films were baked for 30 minutes in a drying oven held at 70° C., 80° C. or 90° C. to obtain a series of coating films.

(218) Each of the obtained coating films was evaluated for low-temperature curability (gel fraction) in accordance with the evaluation method described above. The results are shown below in Table 3.

Examples 3-5 and 3-6

(219) (1) Production of Blocked Polyisocyanate Compositions BL3-5a and BL3-6a

(220) The types and masses of polyisocyanates and blocking agents were altered as shown in Table 3, and blocking reactions were performed. After the blocking reaction, butyl acetate was removed under reduced pressure conditions to adjust the non-volatile fraction to 60%. Subsequently, a solvent 2 (n-butanol) was added, and the mixture was mixed at 40° C. for one hour to obtain blocked polyisocyanate compositions BL3-5a and BL3-6a. The effective NCO content and the non-volatile fraction for each of the obtained blocked polyisocyanate compositions are shown below in Table 3.

(221) (2) Production of Coating Material Compositions T3-5a and T3-6a (Blending Method 1)

(222) Subsequently, using the blocked polyisocyanate compositions obtained above in (1), the same method as that described for (2) of Example 3-1 was used to produce coating material compositions T3-5a and T3-6a. The storage stability of each of the obtained coating material compositions T3-5a and T3-6a was evaluated in accordance with the evaluation method described above. The results are shown below in Table 3.

(223) (3) Production of Coating Films

(224) Subsequently, for each of the coating material compositions obtained above in (2), the same method as that described for (3) of Example 3-1 was used to produce coating films. Each of the obtained coating films was evaluated for low-temperature curability (gel fraction) in accordance with the evaluation method described above. The results are shown below in Table 3.

Examples 3-7 to 3-11

(225) (1) Production of Blocked Polyisocyanate Compositions BL3-7a to BL3-11a

(226) With the exceptions of altering the types and masses of polyisocyanates and blocking agents as shown in Table 3, and not adding the solvent 2 (n-butanol, isobutanol or 2-propanol), the same method as that described for (1) of Example 3-1 was used to produce blocked polyisocyanate compositions BL3-7a to BL3-11a. The effective NCO content and the non-volatile fraction for each of the obtained blocked polyisocyanate compositions are shown below in Table 3.

(227) (2) Production of Coating Material Compositions T3-7a to T3-11a (Blending Method 2)

(228) First, an acrylic polyol (Setalux 1767 (product name) manufactured by Nuplex Resin Inc., resin fraction hydroxyl value: 150 mgKOH/g, resin fraction: 65%) was diluted with butyl acetate. Subsequently, a mass of an active hydrogen compound (isobutanol, 2-propanol or 1,3-butanediol) shown in Table 3 was added to each of the blocked polyisocyanate compositions BL3-7a to BL3-11a obtained above in (1), and with each of the resulting mixtures undergoing constant stirring, the acrylic polyol was added gradually to obtain coating material compositions T3-7a to T3-11a having a total resin fraction of 45%. The blend amounts were adjusted to achieve equivalence between the blocked NCO groups of the blocked polyisocyanate compositions BL3-7a to BL3-11a and the hydroxyl groups of the acrylic polyol. The storage stability of the obtained coating material compositions was evaluated in accordance with the evaluation method described above. The results are shown below in Table 3.

(229) (3) Production of Coating Films

(230) Subsequently, for each of the coating material compositions obtained above in (2), the same method as that described for (3) of Example 3-1 was used to produce coating films. Each of the obtained coating films was evaluated for low-temperature curability (gel fraction) in accordance with the evaluation method described above. The results are shown below in Table 3.

Example 3-121

(231) (1) Production of Blocked Polyisocyanate Composition BL3-12a

(232) With the exceptions of altering the types and masses of polyisocyanate and blocking agent as shown in Table 3, and not adding the solvent 2 (n-butanol, isobutanol or 2-propanol), the same method as that described for (1) of Example 3-1 was used to produce a blocked polyisocyanate composition BL3-12a. The effective NCO content and the non-volatile fraction for the obtained blocked polyisocyanate composition are shown below in Table 3.

(233) (2) Production of Coating Material Composition T3-12a (Blending Method 3)

(234) Subsequently, the blocked polyisocyanate composition BL3-12a obtained above in (1) and an acrylic polyol (Setalux 1767 (product name) manufactured by Nuplex Resin Inc., resin fraction hydroxyl value: 150 mgKOH/g, resin fraction: 65%) were blended so as to achieve equivalence between the blocked NCO groups and the hydroxyl groups of the acrylic polyol. Butyl acetate was then added and mixed, and then finally, the mass of active hydrogen compound (2-propanol) shown in Table 3 was added, thus obtaining a coating material composition T3-12a with a total resin fraction of 45%. The storage stability of the obtained coating material composition was evaluated in accordance with the evaluation method described above. The result is shown below in Table 3.

(235) (3) Production of Coating Films

(236) Subsequently, using the coating material composition obtained above in (2), the same method as that described for (3) of Example 3-1 was used to produce a coating film. The obtained coating film was evaluated for low-temperature curability (gel fraction) in accordance with the evaluation method described above. The result is shown below in Table 3.

Comparative Examples 3-1 and 3-2

(237) (1) Production of Blocked Polyisocyanate Compositions BL3-11b and BL3-2b

(238) With the exceptions of altering the types and masses of polyisocyanates and blocking agents and the reaction conditions as shown in Table 3, the same method as that described for (1) of Example 3-1 was used to conduct blocking reactions. Subsequently, a solvent 2 (n-butanol) was added to the product of the blocking reaction in a mass shown in Table 3, and the mixture was mixed at 80° C. for one hour to obtain blocked polyisocyanate compositions BL3-1b and BL3-2b. The effective NCO content and the non-volatile fraction for each of the obtained blocked polyisocyanate compositions BL3-1b and BL3-2b are shown below in Table 3.

(239) (2) Production of Coating Material Compositions T3-1b and T3-2b (Blending Method 1)

(240) Subsequently, using the blocked polyisocyanate compositions BL3-1b and BL3-2b obtained above in (1), the same method as that described for (2) of Example 3-1 was used to produce coating material compositions T3-1b and T3-2b. The storage stability of each of the obtained coating material compositions was evaluated in accordance with the evaluation method described above. The results are shown below in Table 3.

(241) (3) Production of Coating Films

(242) Subsequently, for each of the coating material compositions T3-1b and T3-2b obtained above in (2), the same method as that described for (3) of Example 3-1 was used to produce coating films. Each of the obtained coating films was evaluated for low-temperature curability (gel fraction) in accordance with the evaluation method described above. The results are shown below in Table 3.

(243) TABLE-US-00003 TABLE 3 Example Example Example Example Example Example Example Example 3-1 3-2 3-3 3-4 3-5 3-6 3-7 3-8 Blocking Polyisocyanate P3-1 P3-1 P3-1 P3-1 P3-1 P3-1 P3-1 P3-1 100 parts 100 parts 100 parts 100 parts 100 parts 100 parts 100 parts 100 parts Blocking di-t-butyl malonate 112 parts 112 parts 112 parts 112 parts 112 parts 112 parts 112 parts agent t-butylethyl  98 parts malonate Diethyl malonate Ethyl acetoacetate 28% sodium  0.9 parts  0.9 parts  0.9 parts  0.8 parts  0.9 parts  0.9 parts  0.9 parts  0.9 parts methylate solution Solvent 1 Butyl acetate 141 parts 141 parts 141 parts 131 parts 318 parts 849 parts 141 parts 141 parts Blocking reaction Temperature, time 40° C. 4 h 40° C. 4 h 40° C. 4 h 40° C. 4 h 40° C. 4 h 40° C. 4 h 40° C. 4 h 40° C. 4 h Solvent removal step performed performed Mixing Solvent 2 (active n-butanol 177 parts 177 parts 177 parts hydrogen group- Isobutanol 177 parts containing compound) 2-propnaol 177 parts 165 parts Mixing Temperature, 40° C. 1 h 40° C. 1 h 40° C. 1 h 40° C. 1 h 40° C. 1 h 40° C. 1 h time Physical Effective NCO content  4.1%  4.1%  4.1%  4.4%  4.1%  4.1%  6.2%  6.2% properties Non-volatile fraction  40%  40%  40%  40%  40%  40%  60%  60% Methane tetracarbonyl fraction  5.1%  4.7%  4.7%  4.8%  1.2%  0.5%  5.2%  5.0% Material Material blending Blending Blending Blending Blending Blending Blending Blending Blending blending method method 1 method 1 method 1 method 1 method 1 method 1 method 2 method 2 Active hydrogen Isobutanol 165 parts 300 parts group-containing 2-propnaol compound 1,3-butanediol Alcohol mol %/NCO 461% 461% 568% 529% 461% 461% 521% 932% Evaluation Gel fraction 70° C.  75%  76%  78%  72%  71%  70%  79%  69% results 80° C.  81%  80%  81%  81%  79%  77%  82%  80% 90° C.  88%  87%  90%  88%  88%  87%  90%  87% Storage stability Viscosity increase ○ 1.2-fold ○ 1.3-fold ○ 1.4-fold ○ 1.4-fold ○ 1.3-fold ○ 1.2-fold ○ 1.3-fold ○ 1.2-fold Example Example Example Example Comparative Comparative 3-9 3-10 3-11 3-12 Example 3-1 Example 3-2 Blocking Polyisocyanate P3-1 P3-1 P3-1 P3-1 P3-1 P3-1 100 parts 100 parts 100 parts 100 parts 100 parts 100 parts Blocking di-t-butyl malonate 112 parts 112 parts 112 parts 112 parts 112 parts agent t-butylethyl malonate Diethyl malonate  61 parts Ethyl acetoacetate  21 parts 28% sodium  0.9 parts  0.9 parts  0.9 parts  0.9 parts  0.8 parts  0.9 parts methylate solution Solvent 1 Butyl acetate 141 parts 141 parts 141 parts 141 parts  45 parts  37 parts Blocking Temperature, 40° C. 4 h 40° C. 4 h 40° C. 4 h 40° C. 4 h 80° C. 3 h 80° C. 4 h reaction time Solvent removal step Mixing Solvent 2 (active n-butanol  76 parts 104 parts hydrogen group- Isobutanol containing 2-propnaol compound) Mixing Temperature, 80° C. 1 h 40° C. 1 h time Physical Effective NCO content  6.2%  6.2%  6.2%  6.2% 7.5%  6.2% properties Non-volatile fraction  60%  60%  60%  60%  60%  60% Methane tetracarbonyl fraction  5.3%  4.8%  4.9%  5.4% 0.0% 19.5%  Material Material blending Blending Blending Blending Blending Blending Blending blending method method 2 method 2 method 2 method 3 method 1 method 1 Active hydrogen Isobutanol 100 parts group-containing 2-propnaol  15 parts 100 parts 165 parts compound 1,3-butanediol 165 parts Alcohol mol %/NCO 46% 561% 521% 521% 271% Evaluation Gel fraction 70° C.  81%  80%  76%  80%   0%  79% results 80° C.  86%  84%  80%  84%  51%  82% 90° C.  91%  90%  88%  90%  80%  91% Storage stability Viscosity increase ○ 2.5-fold ○ 1.3-fold ○ 1.6-fold ○ 1.8-fold ○ 1.2-fold Δ 3.2-fold

(244) The coating films produced using the coating material compositions containing a blocked polyisocyanate composition and an active hydrogen group-containing compound (Examples 3-1 to 3-12) exhibited excellent low-temperature curability, with a gel fraction of at least 87% by mass at a curing temperature of 90° C., a gel fraction of at least 77% by mass at a curing temperature of 80° C., and a gel fraction of at least 69% by mass at a curing temperature of 70° C. Further, the coating material compositions also exhibited excellent storage stability upon storage at 40° C. for 10 days.

(245) In contrast, in Comparative Examples 3-1 and 3-2, a combination of favorable low-temperature curability and favorable storage stability could not be achieved.

(246) The above results confirmed that the coating material composition of an embodiment of the present invention exhibited excellent low-temperature curability and storage stability.

Examples 4-1 to 4-13, and Comparative Example 4-1

(247) <Test Items>

(248) The blocked polyisocyanate compositions produced in the examples and comparative example, the coating material compositions containing those blocked polyisocyanate compositions, and the coating films obtained from the coating material compositions were each subjected to measurement and evaluation of various physical properties in accordance with the methods described below.

(249) [Physical Property 4-1] Isocyanate Group (NCO) Content of Polyisocyanate

(250) First, 1 to 3 g of the polyisocyanate was weighed accurately into a conical flask (W g). Next, 20 mL of toluene was added, and the polyisocyanate was dissolved. Subsequently, 10 mL of a 2N toluene solution of di-n-butylamine was added, and following mixing, the mixture was left to stand for 15 minutes at room temperature. Next, 70 mL of isopropyl alcohol was added and mixed. The resulting liquid was then titrated with a 1N hydrochloric acid solution (factor F) using an indicator. The thus obtained titer was deemed V2 mL. Subsequently, the same operation was repeated without the polyisocyanate, and the obtained titer was deemed V1 mL. The formula (1) shown below was then used to calculate the isocyanate group (NCO) content of the polyisocyanate.
NCO content [% by mass]=(V1−V2)×F×42/(W×1000)×100  (1)
[Physical Property 4-2] Number Average Molecular Weight of Polyisocyanate

(251) Using the polyisocyanate as a sample, the number average molecular weight of the polyisocyanate was determined as the polystyrene-equivalent number average molecular weight by measurement with a gel permeation chromatograph using the apparatus and conditions described below.

(252) (Measurement Conditions)

(253) Apparatus: HLC-802A (manufactured by Tosoh Corporation)

(254) Columns: 1 G1000HXL (manufactured by Tosoh Corporation), 1×G2000HXL (manufactured by Tosoh Corporation), and 1×G3000HXL (manufactured by Tosoh Corporation)

(255) Carrier: tetrahydrofuran

(256) Flow rate: 0.6 mL/minute

(257) Sample concentration: 1.0% by mass

(258) Injection volume: 20 μL

(259) Temperature: 40° C.

(260) Detection method: refractive index detector

(261) [Physical Property 4-3] Average Isocyanate Number of Polyisocyanate

(262) Using the polyisocyanate as a sample, the average isocyanate number was determined using formula (2) shown below.
Average isocyanate number=(number average molecular weight (Mn) of polyisocyanate×NCO content (% by mass)×0.01)/42  (2)
[Physical Property 4-4] Non-Volatile Fraction (Solid Fraction Amount) of Blocked Polyisocyanate Composition

(263) The non-volatile fraction (solid fraction amount) of the blocked polyisocyanate composition was determined in the following manner.

(264) First, an aluminum dish with a base diameter of 38 mm was weighed accurately. About 1 g of the blocked polyisocyanate composition produced in the example or comparative example was then weighed accurately onto the aluminum dish (W1). Subsequently, the blocked polyisocyanate composition was adjusted to a uniform thickness. The blocked polyisocyanate composition mounted on the aluminum dish was then placed in a 105° C. oven for one hour. The aluminum dish was then returned to room temperature, and the blocked polyisocyanate composition remaining on the aluminum dish was weighed accurately (W2). The non-volatile fraction (solid fraction) of the blocked polyisocyanate composition was then calculated from formula (3) shown below.
Solid fraction amount of blocked polyisocyanate composition [% by mass]=W2/W1×100  (3)
[Physical Property 4-5] Effective Isocyanate Group (NCO) Content of Blocked Polyisocyanate Composition

(265) The effective isocyanate group (NCO) content of the blocked polyisocyanate compositions produced in the examples and comparative example was determined in the following manner.

(266) Here, the expression “effective isocyanate group (NCO) content” is a quantification of the amount of blocked isocyanate groups capable of participating in crosslinking reactions that exist within the blocked polyisocyanate composition following the blocking reaction, and is expressed as a % by mass value of the isocyanate groups.

(267) The effective NCO content was calculated using formula (4) shown below. In formula (4), the “NCO content of the polyisocyanate” and the “non-volatile fraction of the blocked polyisocyanate composition” used the values calculated above for the physical property 4-1 and the physical property 4-4 respectively. In those cases where the sample was diluted with a solvent or the like, the effective NCO content value was calculated in the diluted state.
Effective NCO Content [% by mass]=[(solid fraction amount of blocked polyisocyanate composition [% by mass])×{(mass of polyisocyanate used in blocking reaction)×(NCO content of polyisocyanate [% by mass])}]/(mass of blocked polyisocyanate composition following blocking reaction)  (4)
[Physical Property 4-6] Amount of Isocyanurate Trimer in Blocked Polyisocyanate Composition

(268) Using the blocked polyisocyanate composition as a sample, and using the same measurement method as that described for the number average molecular weight of the polyisocyanate determined above in “physical property 4-2”, the blocked polyisocyanate composition was subjected to a gel permeation chromatography measurement. The obtained measurement results were then used to determine the ratio of the surface area for the isocyanurate trimer blocked with three molecules of the blocking agent relative to the surface area for the entire blocked polyisocyanate composition, and this ratio was deemed to represent the amount of the isocyanurate trimer within the blocked polyisocyanate composition.

(269) [Physical Property 4-7] a/(a+b+c+d+e+f)

(270) Using a Biospin Avance 600 (product name) manufactured by Bruker Corporation, a .sup.13C-NMR measurement was conducted under the conditions listed below, and the molar amounts of allophanate groups, isocyanurate groups, uretdione groups, iminooxadiazinedione groups, urethane groups and biuret groups were each determined.

(271) (Measurement Conditions)

(272) .sup.13C-NMR apparatus: AVANCE 600 (manufactured by Bruker Corporation)

(273) CryoProbe CPDUL 600S3-C/H-D-05Z (manufactured by Bruker Corporation)

(274) Resonance frequency: 150 MHz

(275) Concentration: 60 wt/vol %

(276) Shift reference: CDCl.sub.3 (77 ppm)

(277) Accumulation number: 10.000

(278) Pulse program: zgpg 30 (proton perfect decoupling method, waiting time: 2 sec)

(279) Subsequently, based on the obtained measurement results, the following signal integral values were divided by the number of measured carbons, and the resulting values were used to determine the molar amount of each functional group.

(280) Uretdione group: integral value near 157 ppm÷2

(281) Iminooxadiazinedione group: integral value near 144 ppm÷1

(282) Isocyanurate group: integral value near 148 ppm÷3

(283) Allophanate group: integral value near 154 ppm÷1

(284) Urethane group: integral value near 156.5 ppm÷1−allophanate group integral value

(285) Biuret group: integral value near 156 ppm÷2

(286) Subsequently, the molar amounts determined for the allophanate groups, uretdione groups, iminooxadiazinedione groups, isocyanurate groups, urethane groups and biuret groups were labeled a, b, c, d, e and f respectively, and the ratio (a/a+b+c+d+e+f) of the molar amount of allophanate groups (a) relative to the total molar amount of allophanate groups, uretdione groups, iminooxadiazinedione groups, isocyanurate groups, urethane groups and biuret groups (a+b+c+d+e+f) was determined.

(287) [Physical Property 4-8] Amount of Methane Tetracarbonyl Structures in Blocked Polyisocyanate Composition

(288) The amount of methane tetracarbonyl structures relative to the total molar amount within the blocked polyisocyanate composition of polyisocyanates having the compound (I) bonded thereto was calculated using the method described below.

(289) Specifically, based on the results of an .sup.1H-NMR measurement performed using an Avance 600 (product name) manufactured by Bruker BioSpin Corporation, the ratio of the molar amount of methane tetracarbonyl structures relative to the total molar amount of methane tetracarbonyl structures, the keto forms of methane tricarbonyl structures and the enol forms of methane tricarbonyl structures (methane tetracarbonyl structures/(methane tetracarbonyl structures+methane tricarbonyl structure keto forms+methane tricarbonyl structure enol forms)) was determined, and this ratio was deemed the amount of methane tetracarbonyl structures. The measurement conditions were as follows.

(290) (Measurement Conditions)

(291) Apparatus: Avance 600 (product name) manufactured by Bruker BioSpin Corporation

(292) Solvent: deuterated chloroform

(293) Accumulation number: 256

(294) Sample concentration: 5.0% by mass

(295) Chemical shift reference: tetramethylsilane was deemed 0 ppm

(296) Further, the signal integral values described below were divided by the number of measured carbons, and the resulting values were used to determine the molar amounts of the various structures.

(297) NH protons of methane tetracarbonyl structure represented by general formula (II) shown below: near 8.0 ppm, integral value÷2

(298) ##STR00020##
(In general formula (II), R.sup.21, R.sup.22, R.sup.23 and R.sup.24 are the same as R.sup.11, R.sup.12, R.sup.13 and R.sup.14 respectively described above.)

(299) NH proton of keto form of methane tricarbonyl structure represented by general formula (III) shown below and enol form of methane tricarbonyl structure represented by general formula (IV) shown below: near 9.8 ppm, integral value÷1

(300) ##STR00021##
(In general formula (III), R.sup.31, R.sup.32, R.sup.33 and R.sup.34 are the same as R.sup.11, R.sup.12, R.sup.13 and R.sup.14 respectively described above.

(301) In general formula (IV), R.sup.41, R.sup.42, R.sup.43 and R.sup.44 are the same as R.sup.11, R.sup.12, R.sup.13 and R.sup.14 respectively described above.)

(302) NH proton of enol form of methane tricarbonyl structure represented by general formula (V) shown below: near 7.3 ppm integral value÷1

(303) ##STR00022##
(In general formula (V), R.sup.51, R.sup.52, R.sup.53 and R.sup.54 are the same as R.sup.11, R.sup.12, R.sup.13 and R.sup.14 respectively described above.)
[Physical Property 4-9] Amount of Nonionic Hydrophilic Groups in Blocked Polyisocyanate Composition

(304) The ratio of the mass of the compound having a nonionic hydrophilic group that was used relative to the mass of the non-volatile fraction (solid fraction amount) of the blocked polyisocyanate composition was determined, and this ratio was deemed the amount of nonionic hydroxyl groups within the blocked polyisocyanate composition.

(305) [Evaluation 4-1] Low-Temperature Curability of Coating Film

(306) An acrylic dispersion (product name: SETAQUA 6510, manufactured by Nuplex Resin Inc., resin fraction concentration: 42%, hydroxyl group concentration: 4.2% (relative to resin)) was blended with each of the polyisocyanate compositions so as to achieve a ratio (isocyanate group/hydroxyl group) of the molar amount of isocyanate groups relative to the molar amount of hydroxyl groups of 0.8, and a mixed solution having a ratio of the mass of water relative to the mass of dipropylene glycol monomethyl ether (water/dipropylene glycol monomethyl ether) of 90/10 was then added to adjust the solid fraction to 37% by mass, thus obtaining a series of coating material compositions. Subsequently, each of the obtained coating material compositions was applied to a polypropylene plate in an amount sufficient to form a dried film thickness of 40 μm, and the applied composition was then heated and dried at 80° C. for 30 minutes, thus obtaining a cured coating film. The low-temperature curability was evaluated by measuring the gel fraction of the obtained coating film. The gel fraction was determined by immersing the coating film in acetone at 23° C. for 24 hours, and was calculated as the value of the mass of the insoluble portion divided by the mass prior to immersion, expressed as a percentage (% by mass).

(307) The obtained gel fraction was used to evaluate the low-temperature curability against the following evaluation criteria.

(308) (Evaluation Criteria)

(309) OO: gel fraction of at least 80% by mass

(310) O: gel fraction of at least 60% by mass but less than 80% by mass

(311) Δ: gel fraction of less than 60% by mass

(312) [Evaluation 4-2] Water Dispersion Stability of Coating Material Composition

(313) Various coating material compositions were prepared using the same method as that described above for “evaluation 4-1”. Subsequently, 20 g of each of the obtained coating material compositions was stored in a 20 mL glass vial at 23° C., the external appearance of the composition was inspected, and the occurrence or absence of precipitation and/or separation was evaluated over time. The water dispersion stability was evaluated against the following evaluation criteria.

(314) (Evaluation Criteria)

(315) OO: neither precipitation nor separation occurred

(316) O: precipitation or separation occurred at a time exceeding 10 days

(317) Δ: precipitation or separation occurred at a time prior to 10 days

(318) [Evaluation 4-3] Viscosity Stability of Coating Material Composition

(319) Various coating material compositions were prepared using the same method as that described above for “evaluation 4-1”. Subsequently, the viscosity of a 20 g sample of each of the obtained coating material compositions that had been stored in a 20 mL glass vial at 40° C. for 10 days was measured (viscometer: RE-85R manufactured by Toki Sangyo Co., Ltd.). The viscosity stability was evaluated against the following evaluation criteria.

(320) (Evaluation Criteria)

(321) OO: change in viscosity after storage relative to initial viscosity of less than ±30%

(322) O: change in viscosity after storage relative to initial viscosity of at least ±30% but less than ±50%

(323) Δ: change in viscosity after storage relative to initial viscosity of at least ±50%, or a solid formed

(324) [Evaluation 4-4] Coating Film Hardness Retention for Coating Material Composition

(325) Various coating material compositions were prepared using the same method as that described above for “evaluation 4-1”. Subsequently, 20 g of each coating material composition was stored in a 20 mL glass vial at 40° C. for 10 days. The coating material composition following initial preparation and the coating material composition following storage were each applied to a glass plate in an amount sufficient to generate a dried film thickness of 40 μm, and the applied composition was then heated and dried at 100° C. for 30 minutes, thus obtaining a cured coating film. The Konig hardness of each of the obtained coating films was measured, and the coating film hardness retention was evaluated based on the change in the hardness following storage relative to the initial hardness.

(326) The specific evaluation criteria for the coating film hardness retention were as follows.

(327) (Evaluation Criteria)

(328) OO: ratio of hardness following storage to initial hardness (hardness following storage/initial hardness) of less than 1.2

(329) O: hardness following storage/initial hardness of at least 1.2 but less than 1.5

(330) Δ: hardness following storage/initial hardness of 1.5 or greater

(331) [Evaluation 4-5] Water Resistance of Coating Film

(332) Various coating material compositions were prepared using the same method as that described above for “evaluation 4-1”. Subsequently, each of the obtained coating material compositions was applied to a glass plate in an amount sufficient to generate a dried film thickness of 40 μm, and the applied composition was then heated and dried at 100° C. for 30 minutes, thus obtaining a cured coating film. The obtained coating film was immersed in water at 23° C., and after 24 hours, the external appearance of the coating film was inspected and evaluated for the occurrence of coating film cloudiness or blistering. The evaluation criteria for the water resistance were as follows.

(333) (Evaluation Criteria)

(334) O: no occurrence of coating film cloudiness or blistering

(335) Δ: coating film cloudiness or blistering occurred

[Synthesis Example 4-1] Production of Polyisocyanate P4-1

(336) A four-neck flask fitted with a thermometer, a stirring blade and a reflux condenser was charged with 1,000 g of HDI and 33 g of trimethylolpropane under a stream of nitrogen, and the internal temperature of the flask was held at 70° C. while the contents were stirred. Tetramethylammonium hydroxide was then added to the flask, and when the yield reached 48%, phosphoric acid was added to halt the reaction. Following filtering of the reaction liquid, the unreacted HDI was removed using a thin-film distillation device, thus obtaining an isocyanurate polyisocyanate (hereafter sometimes referred to as the “polyisocyanate P4-1”).

(337) The NCO content of the obtained polyisocyanate P4-1 was 19.9% by mass, the number average molecular weight was 1,080, and the average isocyanate group number was 5.1.

[Synthesis Example 4-2] Production of Polyisocyanate P4-2

(338) A four-neck flask fitted with a thermometer, a stirring blade and a reflux condenser was charged with 800 g of HDI, 200 g of IPDI and 75 g of trimethylolpropane under a stream of nitrogen, and the internal temperature of the flask was held at 70° C. while the contents were stirred. Tetramethylammonium hydroxide was then added to the flask, and when the yield reached 46%, phosphoric acid was added to halt the reaction. Following filtering of the reaction liquid, the unreacted HDI and IPDI were removed using a thin-film distillation device, thus obtaining an isocyanurate polyisocyanate (hereafter sometimes referred to as the “polyisocyanate P4-2”).

(339) The NCO content of the obtained polyisocyanate P4-2 was 18.5% by mass, the number average molecular weight was 1,200, and the average isocyanate group number was 5.3.

[Synthesis Example 4-3] Production of Polyisocyanate P4-3

(340) A four-neck flask fitted with a thermometer, a stirring blade and a reflux condenser was charged with 1,000 g of HDI and 2 g of 2-ethylhexane-1,3-diol under a stream of nitrogen, and the internal temperature of the flask was held at 70° C. while the contents were stirred. Tetramethylammonium hydroxide was then added to the flask, and when the yield reached 40%, phosphoric acid was added to halt the reaction. Following filtering of the reaction liquid, the unreacted HDI was removed using a thin-film distillation device, thus obtaining an isocyanurate polyisocyanate (hereafter sometimes referred to as the “polyisocyanate P4-3”).

(341) The NCO content of the obtained polyisocyanate P4-3 was 21.8% by mass, the number average molecular weight was 655, and the average isocyanate group number was 3.4.

[Example 4-1] Production of Blocked Polyisocyanate Composition BL4-1a

(342) A four-neck flask fitted with a thermometer, a stirring blade and a reflux condenser was charged, under a stream of nitrogen, with 100 g of the polyisocyanate P4-1 obtained in Synthesis Example 4-1 and 33 g of a polyethylene oxide (product name: MPG-081, manufactured by Nippon Nyukazai Co., Ltd., number average molecular weight: 690) as a hydrophilic compound, and the mixture was stirred under heating at 120° C. for 4 hours. Subsequently, the reaction liquid was cooled to room temperature, 80 g of diisopropyl malonate and 142 g of dipropylene glycol dimethyl ether (DPDM) were added, 0.9 parts of a methanol solution containing sodium methylate (28% by mass) was then added at room temperature, and a blocking reaction was conducted at 40° C. for 4 hours, thus obtaining a blocked polyisocyanate composition BL4-1a. The obtained blocked polyisocyanate composition BL4-1a had a non-volatile fraction of 60% by mass, an effective NCO content of 5.0% by mass, an amount of isocyanurate trimer of 12% by mass, a value for a/(a+b+c+d+e+f) of 0.28, an amount of methane tetracarbonyl structures of 3.1 mol %, and an amount of nonionic hydrophilic groups of 15.4% by mass.

(343) The low-temperature curability of a coating film obtained using the blocked polyisocyanate composition BL4-1a was evaluated OO, the water dispersion stability of the coating material composition was evaluated OO, the viscosity change for the coating material composition was evaluated OO, the coating film hardness retention for the coating material composition was evaluated OO, and the coating film water resistance was evaluated O. The above physical properties and evaluations are also shown in Table 4.

[Examples 4-2 to 4-13, and Comparative Example 4-1] Production of Blocked Polyisocyanate Compositions BL4-2a to BL4-13a and BL4-1b

(344) With the exceptions of using the types and amounts of polyisocyanates, hydrophilic compounds and blocking agents and the amounts of solvent shown in Table 4, the same method as that described for Example 4-1 was used to produce blocked polyisocyanate compositions.

(345) The types of hydrophilic compounds and blocking agents shown in Table 4 are as follows.

(346) (Hydrophilic Compounds)

(347) H4-1: a polyethylene oxide (product name: MPG-081, manufactured by Nippon Nyukazai Co., Ltd., number average molecular weight: 690)

(348) H4-2: a polyethylene oxide (product name: MPG-130U, manufactured by Nippon Nyukazai Co., Ltd., number average molecular weight: 420)

(349) H4-3: hydroxypivalic acid (HPA) (number average molecular weight: 119)

(350) (Blocking Agents)

(351) B4-1: diisopropyl malonate

(352) B4-2: di-sec-butyl malonate

(353) B4-3: di-tert-butyl malonate

(354) B4-4: di-tert-pentyl malonate

(355) B4-5: tert-butylethyl malonate

(356) B4-6: isopropylethyl malonate

(357) B4-7: diethyl malonate

(358) B4-8: isopropyl acetoacetate

(359) Further, evaluation of various physical properties of the obtained blocked polyisocyanate compositions, and evaluations of the coating material compositions and coating films obtained using the blocked polyisocyanate compositions were conducted using the methods described above. The results are shown in Table 4.

(360) TABLE-US-00004 TABLE 4 Example Example Example Example Example Example Example 4-1 4-2 4-3 4-4 4-5 4-6 4-7 Blocked polyisocyanate composition BL4-1a BL4-2a BL4-3a BL4-4a BL4-5a BL4-6a BL4-7a Polyisocyanate P4-1 P4-1 P4-1 P4-1 P4-1 P4-1 P4-1 100 g 100 g 100 g 100 g 100 g 100 g 100 g Hydrophilic compound H4-1 H4-1 H4-1 H4-1 H4-1 H4-1 H4-1  33 g  33 g  33 g  33 g  33 g  33 g  33 g Blocking agent B4-1 B4-2 B4-3 B4-4 B4-5 B4-6 B4-1  80 g  92 g  92 g  104 g  74 g  68 g  71 g B4-8  14 g Solvent: DPDM 142 g 150 g 150 g 158 g 138 g 134 g 145 g [Physical property 4-4] 60 60 60 60 60 60 60 Non-volatile fraction [% by mass] [Physical property 4-5] 5.0 4.8 4.8 4.5 5.2 5.3 4.9 Effective NCO content [% by mass] [Physical property 4-6] Amount of 12 13 12 13 13 13 14 isocyanurate trimer [% by mass] [Physical property 4-7] 0.28 0.27 0.28 0.29 0.28 0.28 0.26 a/(a + b + c + d + e + f) [Physical property 4-8] Amount of methane 3.1 2.9 3.5 3.1 3.3 3.5 2.8 tetracarbonyl structures [% by mass] [Physical property 4-9] Amount of nonionic 15.4 14.5 14.5 13.8 15.8 16.3 15.0 hydrophilic groups [% by mass] [Evaluation 4-1] ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Low-temperature curability of coating film [Evaluation 4-2] Water dispersion stability ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ of coating material composition [Evaluation 4-3] Viscosity stability of ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ coating material composition [Evaluation 4-4] Coating film hardness ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ retention for coating material composition [Evaluation 4-5] Water ○ ○ ○ ○ ○ ○ ○ resistance of coating film Example Example Example Example Example Example Comparative 4-8 4-9 4-10 4-11 4-12 4-13 Example 4-1 Blocked polyisocyanate composition BL4-8a BL4-9a BL4-10a BL4-11a B.L.4-12a BL4-13a BL4-1b Polyisocyanate P4-2 P4-3 P4-1 P4-1 P4-1 P4-1 P4-1 100 g 100 g 100 g 100 g 100 g 100 g 100 g Hydrophilic compound H4-1 H4-1 H4-2 H4-3 H4-2 H4-2 H4-1  30 g  36 g  20 g  14 g  10 g  6 g  33 g Blocking agent B4-1 B4-1 B4-1 B4-1 B4-1 B4-1 B4-7  75 g  88 g  80 g  67 g  85 g  86 g  68 g Solvent: DPDM 137 g 149 g 133 g 121 g 130 g 128 g 134 g [Physical property 4-4] 60 60 60 60 60 60 60 Non-volatile fraction [% by mass] [Physical property 4-5] 4.9 5.3 5.4 5.9 5.5 5.6 5.3 Effective NCO content [% by mass] [Physical property 4-6] Amount of 11 46 18 20 20 22 13 isocyanurate trimer [% by mass] [Physical property 4-7] 0.31 0.10 0.28 0.29 0.29 0.30 0.28 a/(a + b + c + d + e + f) [Physical property 4-8] Amount of methane 3.0 3.5 3.0 3.1 3.1 2.9 0.0 tetracarbonyl structures [% by mass] [Physical property 4-9] Amount of nonionic 14.8 16.0 9.9 — 5.1 3.1 16.3 hydrophilic groups [% by mass] [Evaluation 4-1] ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Δ Low-temperature curability of coating film [Evaluation 4-2] Water dispersion stability ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Δ of coating material composition [Evaluation 4-3] Viscosity stability of ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Δ coating material composition [Evaluation 4-4] Coating film hardness ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Δ retention for coating material composition [Evaluation 4-5] Water ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ resistance of coating film

(361) Table 4 reveals that for the blocked polyisocyanate compositions BL4-1a to BL4-13a containing a blocked polyisocyanate obtained from a polyisocyanate, the compound (I) as a blocking agent, and a hydrophilic compound (Examples 4-1 to 4-13), coating material compositions of excellent water dispersion stability, viscosity stability and coating film hardness retention were able to be obtained. Further, by using these coating material compositions, coating films having excellent low-temperature curability and water resistance were able to be obtained.

(362) In contrast, for the blocked polyisocyanate composition BL4-1b containing a blocked polyisocyanate obtained from a polyisocyanate, a blocking agent other than the compound (I), and a hydrophilic compound (Comparative Example 4-1), a combination of favorable water dispersion stability, viscosity stability and coating film hardness retention when used as a coating material composition, and favorable low-temperature curability and water resistance when used as a coating film could not be achieved.

(363) Further, in the blocked polyisocyanate compositions BL4-1a to BL4-13a (Examples 4-1 to 4-13), as the amount of the hydrophilic compound was increased, a tendency for improved water dispersion stability of the coating material composition was observed.

(364) Furthermore, in the blocked polyisocyanate compositions BL4-1a, BL4-2a, and BL4-7a to BL4-13a that used either B4-1 (diisopropyl malonate) or B4-2 (di-sec-butyl malonate) as the blocking agent (Examples 4-1, 4-2, and 4-7 to 4-13), the viscosity stability and coating film hardness retention when used as a coating material composition were particularly superior compared with the blocked polyisocyanate compositions BL4-3a to BL4-6a that used the blocking agents B4-3 to B4-6 (Examples 4-3 to 4-6).

(365) Further, the blocked polyisocyanate compositions BL4-11a to BL4-13a in which the amount of nonionic hydrophilic groups was 5.1% by mass or less (Examples 4-11 to 4-13) exhibited particularly favorable water resistance as a coating film compared with the blocked polyisocyanate compositions BL4-1a to BL4-10a in which the amount of nonionic hydrophilic groups was greater than the above value (Examples 4-1 to 4-10).

Examples 5-1 to 5-13, and Comparative Example 5-1

(366) The polyisocyanates synthesized in the synthesis examples, the blocked polyisocyanate compositions produced in the production examples, the adhesive compositions produced in the examples and comparative example, and the easy adhesion treated laminate containing an easy adhesion treated layer obtained by applying the adhesive composition to an adherend were each subjected to measurement and evaluation of various physical properties in accordance with the methods described below.

(367) [Physical Property 5-1] Isocyanate Group (NCO) Content of Polyisocyanate

(368) First, 1 to 3 g of the polyisocyanate was weighed accurately into a conical flask (W g). Next, 20 mL of toluene was added, and the polyisocyanate was dissolved. Subsequently, 10 mL of a 2N toluene solution of di-n-butylamine was added, and following mixing, the mixture was left to stand for 15 minutes at room temperature. Next, 70 mL of isopropyl alcohol was added and mixed. The resulting liquid was then titrated with a 1N hydrochloric acid solution (factor F) using an indicator. The thus obtained titer was deemed V2 mL. Subsequently, the same operation was repeated without the polyisocyanate, and the obtained titer was deemed V1 mL. The formula (1) shown below was then used to calculate the isocyanate group (NCO) content of the polyisocyanate.
NCO content [% by mass]=(V1−V2)×F×42/(W×1000)×100  (1)
[Physical Property 5-2] Number Average Molecular Weight (Mn) of Polyisocyanate

(369) Using the polyisocyanate as a sample, the number average molecular weight (Mn) of the polyisocyanate was determined as the polystyrene-equivalent number average molecular weight by measurement with a gel permeation chromatograph using the apparatus and conditions described below.

(370) (Measurement Conditions)

(371) Apparatus: HLC-802A (manufactured by Tosoh Corporation)

(372) Columns: 1×G1000HXL (manufactured by Tosoh Corporation), 1×G2000HXL (manufactured by Tosoh Corporation), and 1×G3000HXL (manufactured by Tosoh Corporation)

(373) Carrier: tetrahydrofuran

(374) Flow rate: 0.6 mL/minute

(375) Sample concentration: 1.0% by mass

(376) Injection volume: 20 μL

(377) Temperature: 40° C.

(378) Detection method: refractive index detector

(379) [Physical Property 5-3] Average Isocyanate Number of Polyisocyanate

(380) Using the polyisocyanate as a sample, the average isocyanate number was determined using formula (2) shown below.
Average isocyanate number=(number average molecular weight (Mn) of polyisocyanate×NCO content (% by mass)×0.01)/42  (2)
[Physical Property 5-4] Solid Fraction Amount of Blocked Polyisocyanate Composition

(381) The solid fraction amount of the blocked polyisocyanate composition was determined in the following manner.

(382) First, an aluminum dish with a base diameter of 38 mm was weighed accurately. About 1 g of the blocked polyisocyanate composition produced in the example or comparative example was then weighed accurately onto the aluminum dish (W1). Subsequently, the blocked polyisocyanate composition was adjusted to a uniform thickness. The blocked polyisocyanate composition mounted on the aluminum dish was then placed in a 105° C. oven for one hour. The aluminum dish was then returned to room temperature, and the blocked polyisocyanate composition remaining on the aluminum dish was weighed accurately (W2). The solid fraction amount (% by mass) of the blocked polyisocyanate composition was then calculated from formula (3) shown below.
Solid fraction amount of blocked polyisocyanate composition [% by mass]=W2/W1×100  (3)
[Physical Property 5-5] Effective Isocyanate Group (NCO) Content of Blocked Polyisocyanate Composition

(383) The effective isocyanate group (NCO) content of the blocked polyisocyanate composition was determined in the following manner.

(384) Here, the expression “effective isocyanate group (NCO) content” is a quantification of the amount of blocked isocyanate groups capable of participating in crosslinking reactions that exist within the blocked polyisocyanate composition following the blocking reaction, and is expressed as a % by mass value of the isocyanate groups.

(385) The effective NCO content was calculated using formula (4) shown below. In formula (4), the “NCO content of the polyisocyanate” and the “solid fraction amount of the blocked polyisocyanate composition” used the values calculated above for the physical property 5-1 and the physical property 5-4 respectively. In those cases where the sample was diluted with a solvent or the like, the effective NCO content value was calculated in the diluted state.
Effective NCO Content [% by mass]=[(solid fraction amount of blocked polyisocyanate composition [% by mass])×{(mass of polyisocyanate used in blocking reaction)×(NCO content of polyisocyanate [% by mass])}]/(mass of blocked polyisocyanate composition following blocking reaction)  (4)
[Physical Property 5-6] Amount of Isocyanurate Trimer Blocked with Three Molecules of Blocking Agent in Blocked Polyisocyanate Composition

(386) Using the blocked polyisocyanate composition as a sample, and using the same measurement method as that described for the number average molecular weight of the polyisocyanate determined above in “physical property 5-2”, the blocked polyisocyanate composition was subjected to a gel permeation chromatography measurement. The obtained measurement results were then used to determine the ratio of the surface area for the isocyanurate trimer blocked with three molecules of the blocking agent relative to the surface area for the entire blocked polyisocyanate composition, and this ratio was deemed to represent the amount of the isocyanurate trimer blocked with three molecules of the blocking agent within the blocked polyisocyanate composition.

(387) [Physical Property 5-7] Ratio of Molar Amount of Allophanate groups Relative to Total Molar Amount of Allophanate Groups, Uretdione Groups, Iminooxadiazinedione Groups, Isocyanurate Groups, Urethane groups and Biuret Groups a/(a+b+c+d+e+f)

(388) Using a Biospin Avance 600 (product name) manufactured by Bruker Corporation, a .sup.13C-NMR measurement was conducted under the conditions listed below, and the molar amounts of allophanate groups, isocyanurate groups, uretdione groups, iminooxadiazinedione groups, urethane groups and biuret groups in the blocked isocyanate component were each determined.

(389) (Measurement Conditions)

(390) .sup.13C-NMR apparatus: AVANCE 600 (manufactured by Bruker Corporation)

(391) CryoProbe CPDUL 600S3-C/H-D-05Z (manufactured by Bruker Corporation)

(392) Resonance frequency: 150 MHz

(393) Concentration: 60 wt/vol %

(394) Shift reference: CDCl.sub.3 (77 ppm)

(395) Accumulation number: 10,000

(396) Pulse program: zgpg 30 (proton perfect decoupling method, waiting time: 2 sec)

(397) Subsequently, based on the obtained measurement results, the following signal integral values were divided by the number of measured carbons, and the resulting values were used to determine the molar amount of each functional group.

(398) Uretdione group: integral value near 157 ppm÷2

(399) Iminooxadiazinedione group: integral value near 144 ppm÷1

(400) Isocyanurate group: integral value near 148 ppm÷3

(401) Allophanate group: integral value near 154 ppm÷1

(402) Urethane group: integral value near 156.5 ppm÷1−allophanate group integral value

(403) Biuret group: integral value near 156 ppm÷2

(404) Subsequently, the molar amounts determined for the allophanate groups, uretdione groups, iminooxadiazinedione groups, isocyanurate groups, urethane groups and biuret groups were labeled a, b, c, d, e and f respectively, and the ratio (a/a+b+c+d+e+f) of the molar amount of allophanate groups (a) relative to the total molar amount of allophanate groups, uretdione groups, iminooxadiazinedione groups, isocyanurate groups, urethane groups and biuret groups (a+b+c+d+e+f) was determined.

(405) [Physical Property 5-8] Amount of Methane Tetracarbonyl Structures in Blocked Polyisocyanate Composition

(406) The amount of methane tetracarbonyl structures relative to the total molar amount within the blocked polyisocyanate composition of polyisocyanates having the compound (1) bonded thereto was calculated using the method described below.

(407) Specifically, based on the results of an .sup.1H-NMR measurement performed using an Avance 600 (product name) manufactured by Bruker BioSpin Corporation, the ratio of the molar amount of methane tetracarbonyl structures relative to the total molar amount of methane tetracarbonyl structures, the keto forms of methane tricarbonyl structures and the enol forms of methane tricarbonyl structures (methane tetracarbonyl structures/(methane tetracarbonyl structures+methane tricarbonyl structure keto forms+methane tricarbonyl structure enol forms)) was determined, and this ratio was deemed the amount of methane tetracarbonyl structures. The measurement conditions were as follows.

(408) (Measurement Conditions)

(409) Apparatus: Avance 600 (product name) manufactured by Bruker BioSpin Corporation

(410) Solvent: deuterated chloroform

(411) Accumulation number: 256

(412) Sample concentration: 5.0% by mass

(413) Chemical shift reference: tetramethylsilane was deemed 0 ppm

(414) Further, the signal integral values described below were divided by the number of measured carbons, and the resulting values were used to determine the molar amounts of the various structures.

(415) NH protons of methane tetracarbonyl structure represented by general formula (II) shown below: near 8.0 ppm, integral value÷2

(416) ##STR00023##
(In general formula (II), R.sup.21, R.sup.22, R.sup.23 and R.sup.24 are the same as R.sup.11, R.sup.12, R.sup.13 and R.sup.14 respectively described above.)

(417) NH proton of keto form of methane tricarbonyl structure represented by general formula (III) shown below and enol form of methane tricarbonyl structure represented by general formula (IV) shown below: near 9.8 ppm, integral value÷1

(418) ##STR00024##
(In general formula (III), R.sup.31, R.sup.32, R.sup.33 and R.sup.34 are the same as R.sup.11, R.sup.12, R.sup.13 and R.sup.14 respectively described above.

(419) In general formula (IV), R.sup.41, R.sup.42, R.sup.43 and R.sup.44 are the same as R.sup.11, R.sup.12, R.sup.13 and R.sup.14 respectively described above.)

(420) NH proton of enol form of methane tricarbonyl structure represented by general formula (V) shown below: near 7.3 ppm, integral value÷1

(421) ##STR00025##
(In general formula (V), R.sup.51, R.sup.52, R.sup.53 and R.sup.54 are the same as R.sup.11, R.sup.12, R.sup.13 and R.sup.14 respectively described above.)
[Physical Property 5-9] Amount of Nonionic Hydrophilic Groups in Blocked Polyisocyanate Composition

(422) The ratio of the mass of the compound having a nonionic hydrophilic group that was used relative to the mass of the solid fraction amount of the blocked polyisocyanate composition was determined, and this ratio was deemed the amount of nonionic hydroxyl groups within the blocked polyisocyanate composition.

(423) [Production of Laminated Polyester Plate]

(424) A polyethylene terephthalate plate (product name: Super PET Plate PET-6010, film thickness: 4 mm) manufactured by TAXIRON Corporation was used as a polyester plate.

(425) Each of the adhesive compositions prepared with a resin solid fraction of 10% by mass was applied to the surface of an aforementioned polyethylene terephthalate plate with an applicator, and was then dried at 90° C. for 30 minutes. Subsequently, a heat treatment step was conducted at 200° C. for one minute, and the resulting structure was then cooled to obtain an easy adhesion treated polyester plate having an easy adhesion treated layer with a thickness of 0.1 μm.

(426) Further, with the exception of performing the heat treatment step under conditions of 180° C. for one minute, a separate easy adhesion treated polyester plate was produced using the same method as that described above.

(427) Moreover, an ultraviolet-curable acrylic resin having the composition described below was applied to the surface of the easy adhesion treated layer using an applicator, and the plate surface of the resulting structure was then irradiated for 5 minutes with ultraviolet rays having a cumulative dose of 900 mJ/cm.sup.2 using an ultraviolet lamp, thus obtaining a laminated polyester plate having an ultraviolet-cured acrylic resin layer with a thickness of 20 μm.

(428) (Ultraviolet-Curable Acrylic Resin Composition)

(429) 2,2-bis(4-(acryloxydiethoxy)phenyl)propane (NK Ester A-BPE-4 (product name), manufactured by Shin-Nakamura Chemical Co., Ltd.): 50% by mass

(430) Tetrahydrofurfuryl acrylate (Viscoat #150 (product name), manufactured by Osaka Organic Chemistry Industry Ltd.): 40% by mass

(431) Photopolymerization initiator (IRGACURE (a registered trademark) 184 (product name), manufactured by Ciba Specialty Chemicals Inc.): 10% by mass

(432) [Evaluation 5-1] Initial Adhesion

(433) Using a cutting guide with a spacing interval of 2 mm, the ultraviolet-cured acrylic resin layer surface of each of the obtained laminated polyester plates was cut to a depth that only penetrated through the ultraviolet-cured acrylic resin layer to form 100 grid squares. Subsequently, a cellophane adhesive tape (No. 405 manufactured by Nichiban Co., Ltd., width: 24 mm) was affixed to the grid-shaped cut surface and rubbed with an eraser to ensure complete adhesion. The cellophane adhesive tape was then pulled rapidly from ultraviolet-cured acrylic resin layer surface of the laminated polyester plate at a peel angle of 180°, the peeled surface was inspected, and the number of peeled grid squares was counted. The evaluation criteria for the initial adhesion were as follows.

(434) (Evaluation Criteria)

(435) OO: number of peeled grid squares was 0

(436) O: number of peeled grid squares was at least 1 but not more than 20

(437) Δ: number of peeled grid squares was at least 21 but not more than 40

(438) x: number of peeled grid squares was 41 or greater

(439) [Evaluation 5-2] Adhesion Following Humidity and Heat Resistance Test

(440) Each of the obtained laminated polyester plates was left to stand in a high-temperature high-humidity chamber in an environment of 80° C. and 95% RH for 48 hours. Subsequently, the laminated polyester plate was removed and left to stand at normal temperature for 10 hours. Using the same method as the initial adhesion evaluation, the adhesion following a humidity and heat resistance test was then evaluated against the following evaluation criteria

(441) (Evaluation Criteria)

(442) OO: number of peeled grid squares was 0

(443) O: number of peeled grid squares was at least 1 but not more than 20

(444) Δ: number of peeled grid squares was at least 21 but not more than 40

(445) x: number of peeled grid squares was 41 or greater

Synthesis of Polyisocyanates

[Synthesis Example 5-1] Synthesis of Polyisocyanate P5-1

(446) A four-neck flask fitted with a thermometer, a stirring blade and a reflux condenser was charged with 1.000 g of HDI and 33 g of trimethylolpropane under a stream of nitrogen, and the internal temperature of the flask was held at 70° C. while the contents were stirred. Tetramethylammonium hydroxide was then added to the flask, and when the yield reached 48%, phosphoric acid was added to halt the reaction. Following filtering of the reaction liquid, the unreacted HDI was removed using a thin-film distillation device, thus obtaining an isocyanurate polyisocyanate (hereafter sometimes referred to as the “polyisocyanate P5-1”).

(447) The NCO content of the obtained polyisocyanate P5-1 was 19.9% by mass, the number average molecular weight was 1,080, and the average isocyanate group number was 5.1.

[Synthesis Example 5-2] Synthesis of Polyisocyanate P5-2

(448) A four-neck flask fitted with a thermometer, a stirring blade and a reflux condenser was charged with 800 g of HDI, 200 g of IPDI and 75 g of trimethylolpropane under a stream of nitrogen, and the internal temperature of the flask was held at 70° C. while the contents were stirred. Tetramethylammonium hydroxide was then added to the flask, and when the yield reached 46%, phosphoric acid was added to halt the reaction. Following filtering of the reaction liquid, the unreacted HDI and IPDI were removed using a thin-film distillation device, thus obtaining an isocyanurate polyisocyanate (hereafter sometimes referred to as the “polyisocyanate P5-2”).

(449) The NCO content of the obtained polyisocyanate P5-2 was 18.5% by mass, the number average molecular weight was 1,200, and the average isocyanate group number was 5.3.

[Synthesis Example 5-3] Synthesis of Polyisocyanate P5-3

(450) A four-neck flask fitted with a thermometer, a stirring blade and a reflux condenser was charged with 1,000 g of HDI and 2 g of 2-ethylhexane-1,3-diol under a stream of nitrogen, and the internal temperature of the flask was held at 70° C. while the contents were stirred. Tetramethylammonium hydroxide was then added to the flask, and when the yield reached 40%, phosphoric acid was added to halt the reaction. Following filtering of the reaction liquid, the unreacted HDI was removed using a thin-film distillation device, thus obtaining an isocyanurate polyisocyanate (hereafter sometimes referred to as the “polyisocyanate P5-3”).

(451) The NCO content of the obtained polyisocyanate P5-3 was 21.8% by mass, the number average molecular weight was 655, and the average isocyanate group number was 3.4.

Production of Blocked Isocyanate Component

[Production Example 5-1] Production of Blocked Polyisocyanate Composition BL5-1a

(452) A four-neck flask fitted with a thermometer, a stirring blade and a reflux condenser was charged, under a stream of nitrogen, with 100 g of the polyisocyanate P5-1 obtained in Synthesis Example 5-1 and 33 g of a polyethylene oxide (product name: MPG-081, manufactured by Nippon Nyukazai Co., Ltd., number average molecular weight: 690) as a hydrophilic compound, and the mixture was stirred under heating at 120° C. for 4 hours. Subsequently, the reaction liquid was cooled to room temperature, 80 g of diisopropyl malonate and 142 g of dipropylene glycol dimethyl ether (DPDM) were added, 0.9 parts of a methanol solution containing sodium methylate (28% by mass) was then added at room temperature, and a blocking reaction was conducted at 40° C. for 4 hours, thus obtaining a blocked polyisocyanate composition BL5-1a. The obtained blocked polyisocyanate composition BL5-1a had a solid fraction of 60% by mass, an effective NCO content of 5.0% by mass, an amount of isocyanurate trimer of 12% by mass, a value for a/(a+b+c+d+e+f) of 0.28, an amount of methane tetracarbonyl structures of 3.1 mol %, and an amount of nonionic hydrophilic groups of 15.4% by mass.

[Production Examples 5-2 to 5-14] Production of Blocked Polyisocyanate Compositions BL5-2a to BL5-13a and BL5-1b

(453) With the exceptions of using the types and amounts of polyisocyanates, hydrophilic compounds and blocking agents and the amounts of solvent shown in Table 5, the same method as that described for Production Example 5-1 was used to produce blocked polyisocyanate compositions BL5-2a to BL5-13a and BL5-1 b.

(454) The composition and physical properties of each of the obtained blocked polyisocyanate compositions BL5-2a to BL5-13a and BL5-1b are shown in Table 5. In Table 5, the types of hydrophilic compounds and blocking agents are as follows.

(455) (Hydrophilic Compounds)

(456) H5-1: a polyethylene oxide (product name: MPG-081, manufactured by Nippon Nyukazai Co., Ltd., number average molecular weight: 690)

(457) H5-2: a polyethylene oxide (product name: MPG-130U, manufactured by Nippon Nyukazai Co., Ltd., number average molecular weight: 420)

(458) H5-3: hydroxypivalic acid (HPA) (number average molecular weight: 119)

(459) (Blocking Agents)

(460) B5-1: diisopropyl malonate

(461) B5-2: di-sec-butyl malonate

(462) B5-3: di-tert-butyl malonate

(463) B5-4: di-tert-pentyl malonate

(464) B5-5: tert-butylethyl malonate

(465) B5-6: isopropylethyl malonate

(466) B5-7: diethyl malonate

(467) B5-8: isopropyl acetoacetate

(468) TABLE-US-00005 TABLE 5 Production Production Production Production Production Production Production Example 5-1 Example 5-2 Example 5-3 Example 5-4 Example 5-5 Example 5-6 Example 5-7 Blocked polyisocyanate composition BL5-1a BL5-2a BL5-3a BL5-4a BL5-5a BL5-6a BL5-7a Composition Polyisocyanate P5-1 P5-1 P5-1 P5-1 P5-1 P5-1 P5-1 100 g 100 g 100 g 100 g 100 g 100 g 100 g Hydrophilic compound H5-1 H5-1 H5-1 H5-1 H5-1 H5-1 H5-1  33 g  33 g  33 g  33 g  33 g  33 g  33 g Blocking agent B5-1 B5-2 B5-3 B5-4 B5-5 B5-6 B5-1  80 g  92 g  92 g 104 g  74 g  68 g  71 g B5-8  14 g Solvent: DPDM 142 g 150 g 150 g 158 g 138 g 134 g 145 g Physical [Physical property 5-4] 60 60 60 60 60 60 60 properties Solid fraction [% by mass] [Physical property 5-5] 5 4.8 4.8 4.5 5.2 5.3 4.9 Effective NCO content [% by mass] [Physical property 5-6] Amount of 12 13 12 13 13 13 14 isocyanurate trimer [% by mass] [Physical property 5-7] 0.28 0.27 0.28 0.29 0.28 0.28 0.26 a/(a + b + c + d + e + f) [Physical properly 5-8] 3.1 2.9 3.5 3.1 3.3 3.5 2.8 Amount of methane tetracarbonyl structures [% by mass] [Physical property 4-9] 15.4 14.5 14.5 13.8 15.8 16.3 15 Amount of nonionic hydrophilic groups [% by mass ] Production Production Production Production Production Production Production Example 5-8 Example 5-9 Example 5-10 Example 5-11 Example 5-12 Example 5-13 Example 5-14 Blocked polyisocyanate composition BL5-8a BL5-9a BL5-10a BL5-11a BL5-12a BL5-13a BL5-1b Composition Polyisocyanate P5-2 P5-3 P5-1 P5-1 P5-1 P5-1 P5-1 100 g 100 g 100 g 100 g 100 g 100 g 100 g Hydrophilic compound H5-1 H5-1 H5-2 H5-3 H5-2 H5-2 H5-1  30 g  36 g  20 g  14 g  10 g  6 g  33 g Blocking agent B5-1 B5-1 B5-1 B5-1 B5-1 B5-1 B5-7  75 g  88 g  80 g  67 g  85 g  86 g  68 g Solvent: DPDM 137 g 149 g 133 g 121 g 130 g 128 g 134 g Physical [Physical property 5-4] 60 60 60 60 60 60 60 properties Solid fraction [% by mass] [Physical property 5-5] 4.9 5.3 5.4 5.9 5.5 5.6 5.3 Effective NCO content [% by mass] [Physical property 5-6] Amount of 11 46 18 20 20 22 13 isocyanurate trimer [% by mass] [Physical property 5-7] 0.31 0.1 0.28 0.29 0.29 0.3 0.28 a/(a + b + c + d + e + f) [Physical properly 5-8] 3 3.5 3 3.1 3.1 2.9 0 Amount of methane tetracarbonyl structures [% by mass] [Physical property 4-9] 14.8 16 9.9 — 5.1 3.1 16.3 Amount of nonionic hydrophilic groups [% by mass ]
<Production of Binder Resin Component>

(469) A resin composed of 80 parts of a polycarbonate formed from 1,6-hexanediol and diethyl carbonate and having a number average molecular weight of 2,000, 4 parts of a polyethylene glycol having a number average molecular weight of 400, 8 parts of 4,4′-dicyclohexylmethane diisocyanate and 3 parts of dimethylolpropionic acid was neutralized with triethylamine to obtain a polycarbonate resin 1.

Production of Adhesive Compositions

[Example 5-1] Production of Adhesive Composition S5-1a

(470) First, 7.0 parts of the polycarbonate resin 1, 3.0 parts of the blocked polyisocyanate BL5-1a obtained in Production Example 1, 5.0 parts of diethylene glycol dimethyl ether and 85.0 parts of water were added to a flask and mixed under constant stirring. Following addition of all of these components, stirring was continued for a further 10 minutes, thus obtaining an adhesive composition S5-1a with a solid fraction of 10% by mass. The components and proportions in the obtained adhesive composition S5-1a are shown below in Table 6. Using the thus obtained adhesive composition S5-1a, a laminated polyester plate was produced using the method described above, and various evaluations were then conducted. The results are shown below in Table 6.

[Examples 5-2 to 5-13, and Comparative Example 5-1] Production of Adhesive Compositions S5-2a to S5-13a and S5-1b

(471) With the exception of altering the composition as shown in Table 6, adhesive compositions S5-2a to S5-13a and S5-1b were produced using the same method as Example 5-1. The components and proportions in the obtained adhesive compositions S5-2a to S5-13a and S5-1b are shown below in Table 6. Further, using the thus obtained adhesive compositions S5-2a to S5-13a and S5-1b, laminated polyester plates were produced using the method described above, and various evaluations were then conducted. The results are shown below in Table 6.

(472) TABLE-US-00006 TABLE 6 Example Example Example Example Example Example Example 5-1 5-2 5-3 5-4 5-5 5-6 5-7 Adhesive composition S5-1a S5-2a S5-3a S5-4a S5-5a S5-6a S5-7a Composition Binder resin component Polycarbonate 7 7 7 7 7 7 7 resin 1 amount [parts] Crosslinking agent Type BL5-1a BL5-2a BL5-3a BL5-4a BL5-5a BL5-6a BL5-7a component Amount [parts] 3 3 3 3 3 3 3 Water Amount [parts] 85 85 85 85 85 85 85 Diethylene glycol Amount [parts] 5 5 5 5 5 5 5 dimethyl ether Evaluations [Evaluation 5-1] 200° C. × 1 min ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Initial adhesion 180° C. × 1 min ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ [Evaluation 5-2] Adhesion 200° C. × 1 min ○ ○ ○ ○ ○ ○ ○ Δ ○ following humidity 180° C. × 1 min Δ Δ ○ ○ ○ ○ Δ Δ Δ and heat resistance test Example Example Example Example Example Example Comparative 5-8 5-8 5-10 5-11 5-12 5-13 Example 5-1 Adhesive composition S5-8a S5-9a S5-10a S5-11a S5-12a S5-13a S5-1b Composition Binder resin component Polycarbonate 7 7 7 7 7 7 7 resin 1 amount [parts] Crosslinking agent Type BL5-8a BL5-9a BL5-10a BL5-11a BL5-12a BL5-13a BL5-1b component Amount [parts] 3 3 3 3 3 3 3 Water Amount [parts] 85 85 85 85 85 85 85 Diethylene glycol Amount [parts] 5 5 5 5 5 5 5 dimethyl ether Evaluations [Evaluation 5-1] 200° C. × 1 min ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Δ Initial adhesion 180° C. × 1 min ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Δ [Evaluation 5-2] Adhesion 200° C. × 1 min ○ ○ ○ ○ ○ ○ × following humidity 180° C. × 1 min ○ Δ Δ Δ ○ ○ × and heat resistance test

(473) Table 6 reveals that the easy adhesion treated layers obtained by applying the adhesive compositions S5-1a to S5-13a containing a blocked polyisocyanate composition using the compound (I) described above as a blocking agent (Examples 5-1 to 5-13) exhibited both favorable initial adhesion and favorable adhesion following a humidity and heat resistance test, even in those cases where a heat treatment was performed for one minute at a temperature of either 180° C. or 200° C.

(474) Further, in the adhesive compositions S5-1a to S5-7a containing blocked polyisocyanate compositions obtained using different types of blocking agents, the easy adhesion treated layers obtained by applying the adhesive compositions S5-1a to S5-5a containing a blocked polyisocyanate composition that used a single blocking agent B5-1 to B5-5 respectively, exhibited particularly favorable initial adhesion, even in the case of the heat treatment at 200° C. for one minute, compared with the easy adhesion treated layers obtained by applying the adhesive composition S5-6a containing a blocked polyisocyanate composition that used the blocking agent B5-6 and the adhesive composition S5-7a containing a blocked polyisocyanate composition that used a combination of the blocking agents B5-1 and B5-8.

(475) Furthermore, in the adhesive compositions S5-1a to S5-6a containing blocked polyisocyanate compositions obtained using different types of blocking agents, the easy adhesion treated layers obtained by applying the adhesive compositions S5-3a and S5-4a containing a blocked polyisocyanate composition that used the blocking agent B5-3 to B5-4 respectively exhibited particularly favorable adhesion following the humidity and heat resistance test, even in those cases where a heat treatment was performed for one minute at a temperature of either 180° C. or 200° C., compared with the easy adhesion treated layers obtained by applying the adhesive compositions S5-1a, S5-2a, S5-5a and S5-6a containing a blocked polyisocyanate composition that used a different blocking agent.

(476) In contrast, the easy adhesion treated layer obtained by applying the adhesive composition S5-1b containing a blocked polyisocyanate composition that did not use the compound (I) described above as a blocking agent exhibited both inferior initial adhesion and inferior adhesion following the humidity and heat resistance test, even in those cases where a heat treatment was performed for one minute at a temperature of either 180° C. or 200° C.

Examples 6-1 to 6-13, and Comparative Examples 6-1 and 6-2

(477) <Test Items>

(478) The blocked polyisocyanate compositions produced in the examples and comparative examples, the water-based coating material compositions containing those blocked polyisocyanate compositions, and the test plates prepared by coating substrates with coating films obtained from the water-based coating material compositions were each subjected to measurement and evaluation of various physical properties in accordance with the methods described below.

(479) [Physical Property 6-1] Isocyanate Group (NCO) Content of Polyisocyanate

(480) First, 1 to 3 g of the polyisocyanate was weighed accurately into a conical flask (W g). Next, 20 mL of toluene was added, and the polyisocyanate was dissolved. Subsequently, 10 mL of a 2N toluene solution of di-n-butylamine was added, and following mixing, the mixture was left to stand for 15 minutes at room temperature. Next, 70 mL of isopropyl alcohol was added and mixed. The resulting liquid was then titrated with a 1N hydrochloric acid solution (factor F) using an indicator. The thus obtained titer was deemed V2 mL. Subsequently, the same operation was repeated without the polyisocyanate, and the obtained titer was deemed V1 mL. The formula (1) shown below was then used to calculate the isocyanate group (NCO) content of the polyisocyanate.
NCO content [% by mass]=(V1−V2)×F×42/(W×1000)×100  (1)
[Physical Property 6-2] Number Average Molecular Weight (Mn) of Polyisocyanate

(481) Using the polyisocyanate as a sample, the number average molecular weight (Mn) of the polyisocyanate was determined as the polystyrene-equivalent number average molecular weight by performing measurement by gel permeation chromatography (GPC) using the apparatus and conditions described below.

(482) (Measurement Conditions)

(483) Apparatus: HLC-802A (manufactured by Tosoh Corporation)

(484) Columns: 1×G1000HXL (manufactured by Tosoh Corporation), 1×G2000HXL (manufactured by Tosoh Corporation), and 1×G3000HXL (manufactured by Tosoh Corporation)

(485) Carrier: tetrahydrofuran

(486) Flow rate: 0.6 mL/minute

(487) Sample concentration: 1.0% by mass

(488) Injection volume: 20 μL

(489) Temperature: 40° C.

(490) Detection method: refractive index detector

(491) [Physical Property 6-3] Average Isocyanate Number of Polyisocyanate

(492) Using the polyisocyanate as a sample, the average isocyanate number was determined using formula (2) shown below.
Average isocyanate number=(number average molecular weight (Mn) of polyisocyanate×NCO content (% by mass)×0.01)/42  (2)
[Physical Property 6-4] Solid Fraction Amount of Blocked Polyisocyanate Composition

(493) The solid fraction amount of the blocked polyisocyanate composition was determined in the following manner.

(494) First, an aluminum dish with a base diameter of 38 mm was weighed accurately. About 1 g of the blocked polyisocyanate composition produced in the example or comparative example was then weighed accurately onto the aluminum dish (W1).

(495) Subsequently, the blocked polyisocyanate composition was adjusted to a uniform thickness. The blocked polyisocyanate composition mounted on the aluminum dish was then placed in a 105° C. oven for one hour. The aluminum dish was then returned to room temperature, and the blocked polyisocyanate composition remaining on the aluminum dish was weighed accurately (W2). The solid fraction amount (% by mass) of the blocked polyisocyanate composition was then calculated from formula (3) shown below.
Solid fraction amount of blocked polyisocyanate composition [% by mass]=W2/W1×100  (3)
[Physical Property 6-5] Effective Isocyanate Group (NCO) Content of Blocked Polyisocyanate Composition

(496) The effective isocyanate group (NCO) content of the blocked polyisocyanate composition was determined in the following manner.

(497) Here, the expression “effective isocyanate group (NCO) content” is a quantification of the amount of blocked isocyanate groups capable of participating in crosslinking reactions that exist within the blocked polyisocyanate composition following the blocking reaction, and is expressed as a % by mass value of the isocyanate groups.

(498) The effective NCO content was calculated using formula (4) shown below. In formula (4), the “NCO content of the polyisocyanate” and the “solid fraction amount of the blocked polyisocyanate composition” used the values calculated above for the physical property 6-1 and the physical property 6-4 respectively. In those cases where the sample was diluted with a solvent or the like, the effective NCO content value was calculated in the diluted state.
Effective NCO Content [% by mass]=[(solid fraction amount of blocked polyisocyanate composition [% by mass])×{(mass of polyisocyanate used in blocking reaction)×(NCO content of polyisocyanate [% by mass])}]/(mass of blocked polyisocyanate composition following blocking reaction)  (4)
[Physical Property 6-6] Amount of Isocyanurate Trimer Blocked with Three Molecules of Blocking Agent in Blocked Polyisocyanate Composition

(499) Using the blocked polyisocyanate composition as a sample, and using the same measurement method as that described for the number average molecular weight of the polyisocyanate determined above in “physical property 6-2”, the blocked polyisocyanate composition was subjected to a GPC measurement. The obtained measurement results were then used to determine the ratio of the surface area for the isocyanurate trimer blocked with three molecules of the blocking agent relative to the surface area for the entire blocked polyisocyanate composition, and this ratio was deemed to represent the amount of the isocyanurate trimer blocked with three molecules of the blocking agent within the blocked polyisocyanate composition.

(500) [Physical Property 6-7] a/(a+b+c+d+e+f)

(501) Using a Biospin Avance 600 (product name) manufactured by Bruker Corporation, a .sup.13C-NMR measurement was conducted under the conditions listed below, and the molar amounts of allophanate groups, isocyanurate groups, uretdione groups, iminooxadiazinedione groups, urethane groups and biuret groups in the blocked polyisocyanate composition were each determined.

(502) (Measurement Conditions)

(503) .sup.13C-NMR apparatus: AVANCE 600 (manufactured by Bruker Corporation)

(504) CryoProbe CPDUL 600S3-C/H-D-05Z (manufactured by Bruker Corporation)

(505) Resonance frequency: 150 MHz

(506) Concentration: 60 wt/vol %

(507) Shift reference: CDCl.sub.3 (77 ppm)

(508) Accumulation number: 10,000

(509) Pulse program: zgpg 30 (proton perfect decoupling method, waiting time: 2 sec)

(510) Subsequently, based on the obtained measurement results, the following signal integral values were divided by the number of measured carbons, and the resulting values were used to determine the molar amount of each functional group.

(511) Uretdione group: integral value near 157 ppm÷2

(512) Iminooxadiazinedione group: integral value near 144 ppm÷1

(513) Isocyanurate group: integral value near 148 ppm÷3

(514) Allophanate group: integral value near 154 ppm÷1

(515) Urethane group: integral value near 156.5 ppm÷1−allophanate group integral value

(516) Biuret group: integral value near 156 ppm÷2

(517) Subsequently, the molar amounts determined for the allophanate groups, uretdione groups, iminooxadiazinedione groups, isocyanurate groups, urethane groups and biuret groups were labeled a, b, c, d, e and f respectively, and the ratio (a/a+b+c+d+e+f) of the molar amount of allophanate groups (a) relative to the total molar amount of allophanate groups, uretdione groups, iminooxadiazinedione groups, isocyanurate groups, urethane groups and biuret groups (a+b+c+d+e+f) was determined.

(518) [Physical Property 6-8] Amount of Methane Tetracarbonyl Structures in Blocked Polyisocyanate Composition

(519) The amount of methane tetracarbonyl structures relative to the total molar amount within the blocked polyisocyanate composition of polyisocyanates having the compound (I) bonded thereto was calculated using the method described below.

(520) Specifically, based on the results of an .sup.1H-NMR measurement performed using an Avance 600 (product name) manufactured by Bruker BioSpin Corporation, the ratio of the molar amount of methane tetracarbonyl structures relative to the total molar amount of methane tetracarbonyl structures, the keto forms of methane tricarbonyl structures and the enol forms of methane tricarbonyl structures (methane tetracarbonyl structures/(methane tetracarbonyl structures+methane tricarbonyl structure keto forms+methane tricarbonyl structure enol forms)) was determined, and this ratio was deemed the amount of methane tetracarbonyl structures. The measurement conditions were as follows.

(521) (Measurement Conditions)

(522) Apparatus: Avance 600 (product name) manufactured by Bruker BioSpin Corporation

(523) Solvent: deuterated chloroform

(524) Accumulation number: 256

(525) Sample concentration: 5.0% by mass

(526) Chemical shift reference: tetramethylsilane was deemed 0 ppm

(527) Further, the signal integral values described below were divided by the number of measured carbons, and the resulting values were used to determine the molar amounts of the various structures.

(528) NH protons of methane tetracarbonyl structure represented by general formula (II) shown below: near 8.0 ppm, integral value÷2

(529) ##STR00026##
(In general formula (II), R.sup.21, R.sup.22, R.sup.23 and R.sup.24 are the same as R.sup.11, R.sup.12, R.sup.13 and R.sup.14 respectively described above.)

(530) NH proton of keto form of methane tricarbonyl structure represented by general formula (III) shown below and enol form of methane tricarbonyl structure represented by general formula (IV) shown below: near 9.8 ppm, integral value÷1

(531) ##STR00027##
(In general formula (III), R.sup.31, R.sup.32, R.sup.33 and R.sup.34 are the same as R.sup.11, R.sup.12, R.sup.13 and R.sup.14 respectively described above.

(532) In general formula (IV), R.sup.41, R.sup.42, R.sup.43 and R.sup.44 are the same as R.sup.11, R.sup.12, R.sup.13 and R.sup.14 respectively described above.)

(533) NH proton of enol form of methane tricarbonyl structure represented by general formula (V) shown below: near 7.3 ppm, integral value÷1

(534) ##STR00028##
(In general formula (V), R.sup.51, R.sup.52, R.sup.53 and R.sup.51 are the same as R.sup.11, R.sup.12, R.sup.13 and R.sup.14 respectively described above.)
[Physical Property 6-9] Amount of Nonionic Hydrophilic Groups in Blocked Polyisocyanate Composition

(535) The ratio of the mass of the compound having a nonionic hydrophilic group that was used relative to the mass of the solid fraction amount of the blocked polyisocyanate composition was determined, and this ratio was deemed the amount of nonionic hydroxyl groups within the blocked polyisocyanate composition.

(536) [Physical Property 6-10] Hydroxyl Value and Acid Value

(537) The hydroxyl value and the acid value of the coating material were measured in accordance with JIS K1557. Specifically, measurements were conducted using the methods described below.

(538) (1) Measurement of Hydroxyl Value

(539) First, an appropriate amount of the sample was weighed into a conical flask (W g). Subsequently, 25 mL of an acetylation reagent was added dropwise to the flask to dissolve the sample. A condenser was fitted to the conical flask, the joint section was sealed with 1 or 2 drops of pyridine, and the mixture was refluxed for 30 minutes. Following refluxing, the conical flask was cooled, and the condenser and the joint section were rinsed with water, with the rinse water being added to the conical flask. The solution was then transferred to a beaker, and the inside of the conical flask was rinsed with water, with the rinse water being added to the beaker. This solution was then titrated with a 0.5 (c) mol/L solution of sodium hydroxide using an indicator. The obtained titer was deemed V2 mL. The same operation was then repeated without the sample, and the obtained titer was deemed V1 mL. The hydroxyl value was then calculated from formula (5) shown below.
Hydroxyl value [mgKOH/g]=((V1−V2)×c×56.1)/W  (5)
(2) Measurement of Acid Value

(540) A sample of about 50 g was weighed accurately into a 300 mL beaker (W g). Subsequently, 125 mL of acetone was added to dissolve the sample. A potentiometric titration was performed using a 0.1 (c) mol/L solution of sodium hydroxide, and the inflection point (V1 mL) of the thus obtained titration curve was deemed the end point. The same operation was then repeated without the sample, and an inflection point (V2 mL) was determined. The acid value was then calculated from formula (6) shown below.
Acid value [mgKOH/g]=(5.61×(V1−V2)×c)/W  (6)
[Evaluation 6-1] Smoothness

(541) Each test plate was measured using a non-contact surface profiler NewView 600s manufactured by Zygo Corporation, using scanning white light interferometry under conditions including an observation field of view of 2.8×2.1 mm and an objective lens of 2.5 times. Based on the measurement results, the smoothness was evaluated against the following evaluation criteria

(542) (Evaluation Criteria)

(543) O: unevenness in perpendicular direction of less than 0.025 μm

(544) x: unevenness in perpendicular direction of 0.025 μm or greater

(545) [Evaluation 6-2] Clarity

(546) Each test plate was scanned with a Wave Scan DOI (product name) manufactured by BYK-Gardner GmbH, and the Wa value was measured. Based on the measured Wa value, the clarity was evaluated against the following evaluation criteria.

(547) (Evaluation Criteria)

(548) O: Wa value of less than 20

(549) x: Wa value of 20 or greater

(550) [Evaluation 6-3] Water-Resistant Adhesion (Initial)

(551) Each test plate was immersed in 50° C. hot water for 240 hours, and following removal from the water and drying at 20° C. for 12 hours, the multilayer coating film of the test plate was cut into a lattice shape with a cutter to a depth that reached the base substrate, thus forming 100 grid squares with a size of 2 mm×2 mm. A cellophane tape was affixed to the surface, the cellophane tape was then peeled rapidly from the test plate at 20° C., and the number of grid squares of the coating film retained on the test plate was investigated. Based on the number of retained grid squares of the coating film, the water-resistant adhesion (initial) was evaluated against the following evaluation criteria.

(552) (Evaluation Criteria)

(553) O: number of retained grid squares of the coating film was 100

(554) Δ: number of retained grid squares of the coating film was at least 90 but not more than 99

(555) x: number of retained grid squares of the coating film was 89 or fewer

(556) [Evaluation 6-4] Water-Resistant Adhesion (After Storage)

(557) Using each of the water-based coating material compositions that had been stored at 40° C. for one month, a series of test plates having multilayer coating films were produced. Each test plate was immersed in 50° C. hot water for 240 hours, and following removal from the water and drying at 20° C. for 12 hours, the multilayer coating film of the test plate was cut into a lattice shape with a cutter to a depth that reached the base substrate, thus forming 100 grid squares with a size of 2 mm×2 mm. A cellophane tape was affixed to the surface, the cellophane tape was then peeled rapidly from the test plate at 20° C., and the number of grid squares of the coating film retained on the test plate was investigated. Based on the number of retained grid squares of the coating film, the water-resistant adhesion (after storage) was evaluated against the following evaluation criteria.

(558) (Evaluation Criteria)

(559) O: number of retained grid squares of the coating film was 100

(560) Δ: number of retained grid squares of the coating film was at least 90 but not more than 99

(561) x: number of retained grid squares of the coating film was 89 or fewer

Synthesis of Polyisocyanates

[Synthesis Example 6-1] Production of Polyisocyanate P6-1

(562) A four-neck flask fitted with a thermometer, a stirring blade and a reflux condenser was charged with 1.000 g of HDI and 33 g of trimethylolpropane under a stream of nitrogen, and the internal temperature of the flask was held at 70° C. while the contents were stirred. Tetramethylammonium hydroxide was then added to the flask, and when the yield reached 48%, phosphoric acid was added to halt the reaction. Following filtering of the reaction liquid, the unreacted HDI was removed using a thin-film distillation device, thus obtaining an isocyanurate polyisocyanate (hereafter sometimes referred to as the “polyisocyanate P6-1”).

(563) The NCO content of the obtained polyisocyanate P6-1 was 19.9% by mass, the number average molecular weight was 1,080, and the average isocyanate group number was 5.1.

[Synthesis Example 6-2] Production of Polyisocyanate P6-2

(564) A four-neck flask fitted with a thermometer, a stirring blade and a reflux condenser was charged with 800 g of HDI, 200 g of IPDI and 75 g of trimethylolpropane under a stream of nitrogen, and the internal temperature of the flask was held at 70° C. while the contents were stirred. Tetramethylammonium hydroxide was then added to the flask, and when the yield reached 46%, phosphoric acid was added to halt the reaction. Following filtering of the reaction liquid, the unreacted HDI and IPDI were removed using a thin-film distillation device, thus obtaining an isocyanurate polyisocyanate (hereafter sometimes referred to as the “polyisocyanate P6-2”).

(565) The NCO content of the obtained polyisocyanate P6-2 was 18.5% by mass, the number average molecular weight was 1,200, and the average isocyanate group number was 5.3.

[Synthesis Example 6-3] Production of Polyisocyanate P6-3

(566) A four-neck flask fitted with a thermometer, a stirring blade and a reflux condenser was charged with 1,000 g of HDI and 2 g of 2-ethylhexane-1,3-diol under a stream of nitrogen, and the internal temperature of the flask was held at 70° C. while the contents were stirred. Tetramethylammonium hydroxide was then added to the flask, and when the yield reached 40%, phosphoric acid was added to halt the reaction. Following filtering of the reaction liquid, the unreacted HDI was removed using a thin-film distillation device, thus obtaining an isocyanurate polyisocyanate (hereafter sometimes referred to as the “polyisocyanate P6-3”).

(567) The NCO content of the obtained polyisocyanate P6-3 was 21.8% by mass, the number average molecular weight was 655, and the average isocyanate group number was 3.4.

Synthesis of Raw Materials for Water-Based Coating Material Compositions

[Synthesis Example 6-4] Production of Hydroxyl Group-Containing Acrylic Resin (AC)

(568) A reaction vessel fitted with a thermometer, a thermostat, a stirring device, a reflux condenser and a water separator was charged with 60 parts of ethylene glycol monobutyl ether and 15 parts of isobutyl alcohol, and the contents of the vessel were then heated to 110° C. under a stream of nitrogen. When the temperature of the contents reached 110° C., a mixture containing 10 parts of styrene, 48 parts of methyl methacrylate, 26 parts of n-butyl acrylate, 10 parts of 2-hydroxyethyl methacrylate, 6 parts of acrylic acid and 1 part of azobisisobutyronitrile was added dropwise to the reaction vessel over a period of 3 hours. Following completion of the addition, the reaction liquid was aged at 110° C. for 30 minutes, and a mixture containing 1 part of azobisisobutyronitrile and 15 parts of ethylene glycol monobutyl ether was then added dropwise to the reaction vessel over a period of one hour. Following aging of the reaction liquid at 110° C. for an additional one hour, the reaction liquid was cooled and neutralized with an equivalent amount of dimethylaminoethanol, and deionized water was then added to obtain a solution of a hydroxyl group-containing acrylic resin (AC). The solid fraction of the solution of the hydroxyl group-containing acrylic resin was 50%.

[Synthesis Example 6-5] Production of Water-Based Primer Coating Material

(569) 1. Production of Hydroxyl Group-Containing Polyester Resin (PE)

(570) A reaction vessel fitted with a thermometer, a thermostat, a stirring device, a reflux condenser and a water separator was charged with 109 parts of trimethylolpropane, 141 parts of 1,6-hexanediol, 126 parts of 1,2-cyclohexane dicarboxylic anhydride and 120 parts of adipic acid. Subsequently, the temperature of the contents was raised from 160° C. to 230° C. over a period of 3 hours, and the contents were subjected to a condensation reaction at 230° C. for 4 hours while the produced water of condensation was removed by the water separator. In order to add carboxyl groups to the thus obtained condensation reaction product, 38.3 parts of trimellitic anhydride was added to the reaction vessel, and a reaction was conducted at 170° C. for 30 minutes. Subsequently, the contents were diluted with ethylene glycol monobutyl ether, thus obtaining a solution of a hydroxyl group-containing polyester resin (PE) with a solid fraction concentration of 70%. The hydroxyl group-containing polyester resin (PE) had an acid value of 46 mgKOH/g, a hydroxyl value of 150 mgKOH/g, and a number average molecular weight of 1.400.

(571) 2. Preparation of Pigment Dispersion

(572) A mixing vessel was charged with 42.9 parts (solid fraction: 30 parts) of the solution of the hydroxyl group-containing polyester resin (PE) obtained above in “1.”, 112 parts of JR-806 (product name, a rutile titanium dioxide, manufactured by TAYCA Corporation), 8 parts of Ketchen Black EC600J (product name, a conductive carbon, manufactured by Lion Corporation), and 137.1 parts of deionized water, and the contents were mixed. Subsequently, the pH of the contents was adjusted to 8.0 using 2-(dimethylamino)ethanol. The contents and glass beads having a diameter of about 1.3 mm ø as dispersion media were then placed in a wide-mouth glass container, and the wide-mouth glass container was sealed. The wide-mouth glass container was then shaken for 4 hours using a paint shaker, thus obtaining a pigment dispersion.

(573) 3. Production of Water-Based Primer Coating Material

(574) A mixing vessel was charged with 30 parts (solid fraction: 15 parts) of the solution of the hydroxyl group-containing acrylic resin obtained in Synthesis Example 6-4, 50 parts (solid fraction: 15 parts) of TAKELAC WS5000 (product name, a polyurethane dispersion manufactured by Mitsui Takeda Chemicals, Inc., a silanol group-containing self-crosslinking dispersion, solid fraction: 30%), 133.3 parts (solid fraction: 40 parts) of SUPERCHLON E-403 (product name, manufactured by Nippon Paper Industries Co., Ltd., a water dispersion of a chlorinated polypropylene, chlorine content of resin: 15%, solid fraction: 30%), and 300 parts of the pigment dispersion obtained above in “2.”, and the contents were mixed. Subsequently, ACRYSOL ASE-60 (product name, a polyacrylic-based thickener, manufactured by Rohm and Haas Co., Ltd.), 2-(dimethylamino)ethanol and deionized water were used to adjust the pH, the concentration and the viscosity of the mixed liquid, thus obtaining a water-based primer coating material having a pH of 8.0, a solid fraction concentration of 45%, and a viscosity of 40 seconds (Ford cup No. 4, 20° C.).

[Synthesis Example 6-6] Production of Water Dispersion of Acrylic-Modified Polyester Resin

(575) A reaction vessel fitted with a thermometer, a thermostat, a stirrer, a heating device and a fractionating column was charged with 92.4 parts of hexahbydrophthalic anhydride, 52.6 parts of adipic acid, 82.6 parts of 1,6-hexanediol, 10.5 parts of neopentyl glycol, 32 parts of 2-butyl-2-ethyl-1,3-propanediol, 1.96 parts of maleic anhydride, and 0.12 parts of dibutyltin oxide, and the reaction vessel was heated to 160° C. with the contents undergoing constant stirring. Subsequently, the temperature of the contents was gradually raised from 160° C. to 240° C. over a period of 4 hours, and the produced water of condensation was removed by distillation through the fractionating column. Following continuous reaction at 240° C. for 90 minutes, the fractionating column was replaced with a water separator, about 15 parts of toluene was added to the reaction vessel, and the water of condensation was removed by azeotropic distillation of the water and toluene. One hour after addition of the toluene, measurements of the acid value of the contents were started, and when the acid value of the contents fell to less than 3.5, heating was halted. Subsequently, toluene was removed from the reaction vessel by distillation under reduced pressure, the reaction vessel was cooled, and 58 parts of 2-butyl-2-ethyl-1,3-propanediol was then added to the reaction vessel. Following cooling of the reaction vessel to 130° C. a mixture containing 8.7 parts of styrene, 12.2 parts of acrylic acid, 22.7 parts of 2-ethylhexyl acrylate and 2.2 parts of tert-butylperoxy-2-ethylhexanoate was added dropwise to the reaction vessel over a period of two hours. The 130° C. temperature was maintained for 30 minutes, an additional 0.44 parts of tert-butylperoxy-2-ethylhexanoate was added as additional catalyst to the reaction vessel, and the reaction mixture was aged for one hour. The reaction vessel was then cooled to 85° C., the contents were neutralized with 14.6 parts of dimethylethanolamine, 468.7 parts of deionized water was added to the contents, and the contents were dispersed in the water to obtain a water dispersion of an acrylic-modified water-based polyester resin having a solid fraction of 35%. The thus obtained acrylic-modified water-based polyester resin had an acid value of 35 mgKOH/g, a hydroxyl value of 11 mgKOH/g, and a number average molecular weight of 13,000.

[Synthesis Example 6-7] Production of Water Dispersion of Acrylic-Based Polymer Microparticles

(576) 1. Preparation of Monomer Emulsion for Core Portion

(577) A monomer emulsion for a core portion was obtained by mixing 54 parts of deionized water, 3.1 parts of ADEKA REASOAP SR-1025, 1 part of allyl methacrylate, 10 parts of styrene, 35 parts of n-butyl acrylate, 10 parts of methyl methacrylate, 20 parts of ethyl acrylate, and 1 part of 2-hydroxyethyl methacrylate.

(578) 2. Preparation of Monomer Emulsion for Shell Portion

(579) A monomer emulsion for a shell portion was obtained by mixing 50 parts of deionized water, 1.8 parts of ADEKA REASOAP SR-1025, 0.04 parts of a 6% aqueous solution of ammonium persulfate, 5.3 parts of 2-hydroxyethyl methacrylate, 2.6 parts of methacrylic acid, 8 parts of ethyl acrylate, and 7.1 parts of methyl methacrylate.

(580) 3. Production of Water Dispersion of Acrylic-Based Polymer Microparticles

(581) A reaction vessel fitted with a thermometer, a thermostat, a stirring device, a reflux condenser, a nitrogen inlet tube, and a dropping funnel was charged with 120 parts of deionized water and 0.8 parts of ADEKA REASOAP SR-1025 (product name, manufactured by ADEKA Corporation, an emulsifying agent, active ingredient: 25%), and the reaction vessel was heated to 80° C. while the contents were stirred under a stream of nitrogen. Subsequently, 5% of the total mass of the monomer emulsion for a core portion obtained in “1.” and 2.5 parts of a 6% aqueous solution of ammonium persulfate were added to the reaction vessel, and the temperature was held at 80° C. for 15 minutes. The remainder of the monomer emulsion for a core portion was then added dropwise to the reaction vessel over a period of 3 hours with the same temperature maintained, and following completion of the dropwise addition, the reaction mixture was aged for one hour. Next, the monomer emulsion for a shell portion obtained in “2.” was added dropwise over a period of one hour, and following subsequent aging for an additional one hour, 3.8 parts of a 5% aqueous solution of 2-(dimethylamino)ethanol was added gradually to the reaction container while the container was cooled to 30° C., and the reaction mixture was then discharged and filtered through a 100-mesh nylon cloth, thus obtaining a water dispersion of acrylic-based polymer microparticles having an average particle size of 100 nm and a solid fraction of 30%. The thus obtained acrylic-based polymer microparticles had an acid value of 17.2 mgKOH/g and a hydroxyl value of 27.2 mgKOH/g.

[Synthesis Example 6-8] Production of Luminescent Pigment Dispersion (AL)

(582) 1. Preparation of Phosphate Group-Containing Polymerizable Unsaturated Monomer

(583) A reaction vessel fitted with a thermometer, a thermostat, a stirrer, a reflux condenser, a nitrogen inlet tube, and a dropping funnel was charged with 57.5 parts of monobutylphosphoric acid and 41 parts of isobutanol, the temperature of the reaction vessel was then raised to 90° C., 42.5 parts of glycidyl methacrylate was added dropwise to the reaction vessel over a period of two hours, and the contents were then aged for one hour under constant stirring. Subsequently, 59 parts of isopropanol was added to the reaction vessel, thus obtaining a solution of a phosphate group-containing polymerizable unsaturated monomer with a solid fraction concentration of 50%. The thus obtained phosphate group-containing polymerizable unsaturated monomer had an acid value derived from the phosphate groups of 285 mgKOH/g.

(584) 2. Preparation of Solution of Phosphate Group-Containing Dispersion Resin

(585) A reaction vessel fitted with a thermometer, a thermostat, a stirrer, a reflux condenser, a nitrogen inlet tube, and a dropping funnel was charged with a mixed solvent containing 27.5 parts of methoxypropanol and 27.5 parts of isobutanol, the reaction vessel was then heated to 110° C., and 121.5 parts of a mixture containing 25 parts of styrene, 27.5 parts of n-butyl methacrylate, 20 parts of isostearyl acrylate (product name, a branched higher alkyl acrylate, manufactured by Osaka Organic Chemical Industry Co., Ltd.), 7.5 parts of 4-hydroxybutyl acrylate, 15 parts of the phosphate group-containing polymerizable unsaturated monomer obtained in “1.”, 12.5 parts of 2-methacryloyloxyethyl acid phosphate, 10 parts of isobutanol and 4 parts of tert-butylperoxy octanoate was then added to the reaction vessel over a period of 4 hours. Subsequently, a mixture containing 0.5 parts of tert-butylperoxy octanoate and 20 parts of isopropanol was added dropwise to the reaction vessel over a period of one hour. The contents were then aged for one hour under constant stirring, thus obtaining a solution of a phosphate group-containing dispersion resin with a solid fraction concentration of 50%. The thus obtained phosphate group-containing dispersion resin had an acid value of 83 mgKOH/g, a hydroxyl value of 29 mgKOH/g, and a weight average molecular weight of 10,000.

(586) 3. Production of Luminescent Pigment Dispersion (AL)

(587) A mixing vessel was charged with 17.5 parts of an aluminum pigment paste GX-180A (product name, manufactured by Asahi Kasei Metals Ltd., metal content: 74%), 34.8 parts of 2-ethyl-1-hexanol, 10 parts (solid fraction: 5 parts) of the solution of the phosphate group-containing dispersion resin obtained in “2.”, and 0.2 parts of 2-(dimethylamino)ethanol, and the contents were mixed uniformly to obtain a luminescent pigment dispersion (AL).

Production of Test Plates

[Example 6-1] Production of Test Plate S6-1a

(588) 1. Production of Blocked Polyisocyanate Composition BL6-1a

(589) A four-neck flask fitted with a thermometer, a stirring blade and a reflux condenser was charged, under a stream of nitrogen, with 100 g of the polyisocyanate P6-1 obtained in Synthesis Example 6-1 and 33 g of a polyethylene oxide (product name: MPG-081, manufactured by Nippon Nyukazai Co., Ltd., number average molecular weight: 690) as a hydrophilic compound, and the mixture was stirred under heating at 120° C. for 4 hours. Subsequently, the reaction liquid was cooled to room temperature, 80 g of diisopropyl malonate and 142 g of dipropylene glycol dimethyl ether (DPDM) were added, 0.9 parts of a methanol solution containing sodium methylate (28% by mass) was then added at room temperature, and a blocking reaction was conducted at 40° C. for 4 hours, thus obtaining a blocked polyisocyanate composition BL6-1a. Various physical properties of the obtained blocked polyisocyanate composition BL6-1a were measured using the methods described above, and revealed a solid fraction amount of 60% by mass, an effective NCO content of 5.0% by mass, an amount of isocyanurate trimer of 12% by mass, a value for a/(a+b+c+d+e+f) of 0.28, an amount of methane tetracarbonyl structures of 3.1 mol %, and an amount of nonionic hydrophilic groups of 15.4% by mass.

(590) 2. Production of Water-Based Coating Material Composition T6-1a

(591) A mixing vessel was charged with 50.0 parts (solid fraction: 40 parts) of the water dispersion of the acrylic-modified polyester resin obtained in Synthesis Example 6-4, 33.3 parts (solid fraction: 20 parts) of the solution of the blocked polyisocyanate composition BL6-1a obtained in “1.”, 133.3 parts (solid fraction: 35 parts) of the water dispersion of the acrylic-based polymer microparticles obtained in Synthesis Example 6-7, 67.5 parts (resin solid fraction: 5 parts) of the luminescent pigment dispersion (AL) obtained in Synthesis Example 6-8, and 10 parts of 2-ethyl-1-hexanol, and the contents were uniformly mixed. Subsequently, ACRYSOL ASE-60, 2-(dimethylamino)ethanol and deionized water were used to adjust the pH, the solid fraction concentration and the viscosity of the mixed liquid, thus obtaining a water-based coating material composition T6-1a having a pH of 8.0, a solid fraction concentration of 25%, and a viscosity of 40 seconds (Ford cup No. 4, 20° C.).

(592) 3. Production of Test Plate S6-1a

(593) The primer coating liquid obtained in Synthesis Example 6-5 was applied by air spraying to a degreased polypropylene plate (PP plate) in an amount sufficient to generate a cured film thickness of 15 μm, thereby forming an uncured primer coating film on the PP plate. The PP plate having the uncured primer coating film was left to stand for 3 minutes, and was then preheated at 60° C. for 3 minutes. Subsequently, the water-based coating material composition T6-a1 was applied by air spraying to the PP plate having the uncured primer coating film in an amount sufficient to generate a cured film thickness of 15 μm, thereby forming an uncured basecoat coating film on top of the uncured primer coating film. The PP plate having the uncured basecoat coating film was left to stand for 5 minutes, and was then preheated at 60° C. for 5 minutes. Subsequently, a clear coating material “Soflex #520 Clear” (product name, manufactured by Kansai Paint Co., Ltd., a two-component acrylic urethane organic solvent-based clear coating material containing a polyisocyanate compound) was applied by air spraying to the PP plate having the uncured basecoat coating film in an amount sufficient to generate a cured film thickness of 35 μm, thereby forming an uncured clear coating film on top of the uncured basecoat coating film. The PP plate having the uncured clear coating film was left to stand for 7 minutes, and was then heated at 80° C. for 30 minutes, thereby simultaneously curing the primer coating film, the basecoat coating film and the clear coating film, and completing production of a test plate S6-1a. Using the obtained test plate S6-1a, various evaluations were conducted using the methods described above. The results are shown below in Table 7.

[Examples 6-2 to 6-13, and Comparative Example 6-1] Production of Multilayer Coating Film Laminates S6-2a to S6-13a and S6-1b

(594) 1. Production of Blocked Polyisocyanate Compositions BL6-2a to BL6-13a and BL6-1b

(595) With the exceptions of using the types and amounts of polyisocyanates, hydrophilic compounds and blocking agents and the amounts of solvent shown in Table 7, the same method as that described for Example 6-1 was used to produce blocked polyisocyanate compositions BL6-2a to BL6-13a and BL6-1b. Various physical properties of each of the blocked polyisocyanate compositions were measured using the methods described above. The results are shown below in Table 7.

(596) 2. Production of Water-Based Coating Material Compositions T6-2a to T6-13a and T6-1b

(597) Subsequently, with the exception of using each of the blocked polyisocyanate compositions BL6-2a to BL6-13a and BL6-1 b obtained in “1.” instead of the blocked polyisocyanate composition BL6-1a, the same method as that described for Example 6-1 was used to produce water-based coating material compositions T6-2a to T6-13a and T6-1b.

(598) 3. Production of Test Plates S6-2a to S6-13a and S6-1b

(599) Next, with the exception of using each of the water-based coating material compositions T6-2a to T6-13a and T6-1b obtained in “2.” instead of the water-based coating material composition T6-1a, the same method as that described for Example 6-1 was used to produce test plates S6-2a to S6-13a and S6-1b. Using the thus obtained test plates S6-2a to S6-13a and S6-1b, various evaluations were conducted using the methods described above. The results are shown below in Table 7.

[Comparative Example 2] Production of Test Plate S6-2b

(600) 1. Production of Blocked Polyisocyanate Composition BL6-2b

(601) A four-neck flask fitted with a thermometer, a stirring blade and a reflux condenser was charged, under a stream of nitrogen, with 100 g of the polyisocyanate P6-3 obtained in Synthesis Example 6-3 and 17 g of a polyethylene oxide (product name: MPG-130U, manufactured by Nippon Nyukazai Co., Ltd., number average molecular weight: 420) as a hydrophilic compound, and the mixture was stirred under heating at 120° C. for 4 hours. Subsequently, the reaction liquid was cooled to room temperature, 70 g of diisopropyl malonate and 34 g of DPDM were added, 0.9 parts of a methanol solution containing sodium methylate (28% by mass) was then added at room temperature, and a blocking reaction was conducted at 65° C. for 8 hours. Subsequently, 189 parts of 4-methyl-2-pentanol was added to the reaction liquid, and solvent was removed by distillation at 80° C. over a period of 3 hours, thus obtaining a blocked polyisocyanate composition BL6-2b. Various physical properties of the obtained blocked polyisocyanate composition BL6-2b were measured using the methods described above, and revealed a solid fraction amount of 60% by mass, an effective NCO content of 6.5% by mass, an amount of isocyanurate trimer of 47% by mass, a value for a/(a+b+c+d+e+f) of 0.10, an amount of methane tetracarbonyl structures of 13 mol %, and an amount of nonionic hydrophilic groups of 9.1% by mass.

(602) 2. Production of Water-Based Coating Material Composition T6-2b

(603) Subsequently, with the exception of using the blocked polyisocyanate composition BL6-2b obtained in “1.” instead of the blocked polyisocyanate composition BL6-1a, the same method as that described for Example 6-1 was used to produce a water-based coating material composition T6-2b.

(604) 3. Production of Test Plate S6-2b

(605) Next, with the exception of using the water-based coating material composition T6-2b obtained in “2.” instead of the water-based coating material composition T6-1a, the same method as that described for Example 6-1 was used to produce a test plate S6-2b. Using the thus obtained test plate S6-2b, various evaluations were conducted using the methods described above. The results are shown below in Table 7.

(606) The types of hydrophilic compounds and blocking agents shown in Table 7 are as follows.

(607) (Hydrophilic Compounds)

(608) H6-1: a polyethylene oxide (product name: MPG-081, manufactured by Nippon Nyukazai Co., Ltd., number average molecular weight: 690)

(609) H6-2: a polyethylene oxide (product name: MPG-130U, manufactured by Nippon Nyukazai Co., Ltd., number average molecular weight: 420)

(610) H6-3: hydroxypivalic acid (HPA) (number average molecular weight: 119)

(611) (Blocking Agents)

(612) B6-1: diisopropyl malonate

(613) B6-2: di-sec-butyl malonate

(614) B6-3: di-tert-butyl malonate

(615) B6-4: di-tert-pentyl malonate

(616) B6-5: tert-butylethyl malonate

(617) B6-6: isopropylethyl malonate

(618) B6-7: diethyl malonate

(619) B6-8: isopropyl acetoacetate

(620) TABLE-US-00007 TABLE 7 Example Example Example Example Example Example Example Example 6-1 6-2 6-3 6-4 6-5 6-6 6-7 6-8 Water-based coating material composition T6-1a T6-2a T6-3a T6-4a T6-5a T6-6a T6-7a T6-8a Blocked polyisocyanate composition BL6-1a BL6-2a BL6-3a BL6-4a BL6-5a BL6-6a BL6-7a BL6-8a Raw materials Polyisocyanate P6-1 P6-1 P6-1 P6-1 P6-1 P6-1 P6-1 P6-2 of blocked 100 g 100 g 100 g 100 g 100 g 100 g 100 g 100 g polyisocyanate Hydrophilic compound H6-1 H6-1 H6-1 H6-1 H6-1 H6-1 H6-1 H6-1 composition  33 g  33 g  33 g  33 g  33 g  33 g  33 g  30 g Blocking agent B6-1 B6-2 B6-3 B6-4 B6-5 B6-6 B6-1 B6-1  80 g  92 g  92 g 104 g  74 g  68 g  71 g  75 g B6-8  14 g 4-methyl-2-pentanol Solvent: DPDM 142 g 150 g 150 g 158 g 138 g 134 g 145 g 137 g Physical [Physical property 6-4] 60 60 60 60 60 60 60 60 properties Solid fraction amount [% by mass] [Physical property 6-5] 5 4.8 4.8 4.5 5.2 5.3 4.9 4.9 Effective NCO content [% by mass] [Physical property 6-6] 12 13 12 13 13 13 14 11 Amount of isocyanurate trimer [% by mass] [Physical property 6-7] 0.28 0.27 0.28 0.29 0.28 0.28 0.26 0.31 a/(a + b + c + d + e + f) [Physical property 6-8] Amount of methane 3.1 1.9 3.5 3.1 3.3 3.5 2.8 3 tetracarbonyl structures [mol %] [Physical property 6-9] Amount of nonionic 15.4 14.5 14.5 13.8 15.8 16.3 15 14.8 hydrophilic groups [% by mass] Evaluations [Evaluation 6-1] Smoothness ○ ○ ○ ○ ○ ○ ○ ○ [Evaluation 6-2] Clarity ○ ○ ○ ○ ○ ○ ○ ○ [Evaluation 6-3] Water-resistant ○ ○ ○ ○ ○ ○ ○ ○ adhesion (initial) [Evaluation 1-4] Water-resistant ○ ○ ○ ○ ○ ○ ○ ○ adhesion (after storage) Example Example Example Example Example Comparative Comparative 6-9 6-10 6-11 6-12 6-13 Example 6-1 Example 6-2 Water-based coating material composition T6-9a T6-10a T6-11a T6-12a T6-13a T6-1b T6-2b Blocked polyisocyanate composition BL6-9a BL6-10a BL6-11a BL6-12a BL6-13a BL6-1b BL6-2b Raw materials Polyisocyanate P6-3 P6-1 P6-1 P6-1 P6-1 P6-1 P6-3 of blocked 100 g 100 g 100 g 100 g 100 g 100 g 100 g polyisocyanate Hydrophilic compound H6-1 H6-2 H6-3 H6-2 H6-2 H6-1 H6-2 composition  36 g  20 g  14 g  10 g  6 g  33 g  17 g Blocking agent B6-1 B6-1 B6-1 B6-1 B6-1 B6-7 B6-1  88 g  80 g  67 g  85 g  86 g  68 g  70 g 4-methyl-2-pentanol 189 g Solvent: DPDM 149 g 133 g 121 g 130 g 128 g 134 g  34 g Physical [Physical property 6-4] 60 60 60 60 60 60 60 properties Solid fraction amount [% by mass] [Physical property 6-5] 5.3 5.4 5.9 5.5 5.6 5.3 6.5 Effective NCO content [% by mass] [Physical property 6-6] 46 18 20 20 22 13 47 Amount of isocyanurate trimer [% by mass] [Physical property 6-7] 0.1 0.28 0.29 0.29 0.3 0.28 0.1 a/(a + b + c + d + e + f) [Physical property 6-8] Amount of methane 3.5 3 3.1 3.1 2.9 — 13 tetracarbonyl structures [mol %] [Physical property 6-9] Amount of nonionic 16 9.9 — 5.1 3.1 16.3 9.1 hydrophilic groups [% by mass] Evaluations [Evaluation 6-1] Smoothness ○ ○ ○ ○ ○ × ○ [Evaluation 6-2] Clarity ○ ○ ○ ○ ○ × ○ [Evaluation 6-3] Water-resistant ○ ○ ○ ○ ○ Δ Δ adhesion (initial) [Evaluation 1-4] ○ ○ ○ ○ ○ Δ Δ Water-resistant adhesion (after storage)

(621) Table 7 reveals that the test plates S6-1a to S6-13a that used the water-based coating material compositions containing blocked polyisocyanate compositions that used the compound (I) as the blocking agent and has an amount of methane tetracarbonyl structures of not more than 10 mol % (Examples 6-1 to 6-13) exhibited favorable results for all of the smoothness, the clarity, and the water-resistant adhesion, both initially and following storage.

(622) In contrast, the test plate S6-1 b that used a water-based coating material composition containing a blocked polyisocyanate composition that used a blocking agent other than the compound (I) (Comparative Example 6-1) exhibited inferior results for each of the smoothness, the clarity, and the water-resistant adhesion, both initially and following storage. Further, the test plate S6-2b that used a water-based coating material composition containing a blocked polyisocyanate composition for which the amount of methane tetracarbonyl structures exceeded 10 mol % (Comparative Example 6-2) exhibited favorable results for the external appearance properties such as the smoothness and the clarity, but exhibited poor water-resistant adhesion, both initially and following storage.

INDUSTRIAL APPLICABILITY

(623) The blocked polyisocyanate composition of an embodiment of the present invention can be used favorably as the curing agent for a coating material composition. A coating material composition of an embodiment of the present invention exhibits excellent viscosity stability, and superior low-temperature curability, hardness retention and water resistance when used as a coating film, and can therefore be used favorably for coating materials having low heat resistance.

(624) An adhesive composition of an embodiment of the present invention can provide an adhesive composition having excellent initial adhesion to adherends and excellent adhesion following a humidity and heat resistance test. An easy adhesion treated laminate of an embodiment of the present invention contains an easy adhesion treated layer formed from the above adhesive composition, and exhibits excellent adhesion to adherends and excellent adhesion following a humidity and heat resistance test.

(625) A multilayer coating film laminate of an embodiment of the present invention can be cured at low temperature, exhibits excellent coating film external appearance, adhesion and water resistance, and can be used favorably for exterior plate components for automobile bodies or automobile components or the like.