Polyaspartic coating composition, coating film, and coated article

Abstract

The present invention provides a polyaspartic coating composition containing (A) an aspartic acid ester compound represented by the following formula (I) ##STR00001## [in formula (I), X is an n-valent organic group, and R.sub.1 and R.sub.2 are organic groups which are inert to the isocyanate group under a reaction condition, and n is an integer of 2 or more.], and (B) a polyisocyanate obtained by using one or more diisocyanate monomers selected from the group consisting of an aliphatic and alicyclic diisocyanate and a polycaprolactone polyol having a number-average molecular weight of 500 to 1,500, wherein a ratio of the polycaprolactone polyol is 20% by mass or more, and the polyisocyanate component contains 10.0% by mass or less of an isocyanurate trimer.

Claims

1. A method for preventing corrosion of a structure, comprising: coating the structure with a polyaspartic coating composition, comprising: (A) an aspartic acid ester compound represented by the following formula (I) ##STR00006## wherein X is an n-valent organic group obtained by removing a primary amino group of an n-valent polyamine, and R.sub.1 and R.sub.2 are the same or different organic groups which are inert to the isocyanate group under a reaction condition, and n is an integer of 2 or more, and (B) a polyisocyanate component obtained by reacting one or two or more diisocyanate monomers selected from the group consisting of an aliphatic and alicyclic diisocyanate with a polycaprolactone polyol having a number-average molecular weight of 500 to 1,500, wherein a ratio of the polycaprolactone polyol to a total amount of the polyol is 20% by mass or more, the polyisocyanate component contains 10.0% by mass or less of an isocyanurate trimer with respect to a total amount of the polyisocyanate component, the structure is a bridge, a highway, a power transmission tower, or a wind power generation blade, and the polyol further contains a polyoxyalkylene polyol.

2. The method according to claim 1, wherein a ratio of the polyoxyalkylene polyol to a total amount of the polyoxyalkylene polyol and the polycaprolactone polyol is 80% by mass or less.

3. The method according to claim 1, wherein an equivalent ratio between the amino group of (A) the aspartic acid ester compound and the isocyanate group of (B) the polyisocyanate component is amino group:isocyanate group=10:1 to 1:10.

4. A method for preventing corrosion of a structure, comprising: coating the structure with a polyaspartic coating composition, comprising: (A) an aspartic acid ester compound represented by the following general formula ##STR00007## wherein X is an n-valent organic group obtained by removing a primary amino group of an n-valent polyamine, and R.sub.1 and R.sub.2 are the same or different organic groups which are inert to the isocyanate group under a reaction condition, and n is an integer of 2 or more, and (B′) a polyisocyanate component obtained by reacting one or two or more diisocyanate monomers selected from the group consisting of an aliphatic diisocyanate and an alicyclic diisocyanate, wherein an average number of isocyanate groups in the polyisocyanate component is 3.5 to 10, a number-average molecular weight of the polyisocyanate component is 870 to 2,000, and the structure is a bridge, a highway, a power transmission tower, or a wind power generation blade.

5. The method according to claim 4, wherein an equivalent ratio between the amino group of (A) the aspartic acid ester compound and the isocyanate group of (B′) the polyisocyanate component is amino group:isocyanate group=10:1 to 1:10.

6. The method according to claim 1, wherein the diisocyanate monomer contains a hexamethylene diisocyanate.

7. Use of a polyaspartic coating composition for heavy-duty anticorrosion coating of bridges, highways, power transmission towers, or wind power generation blades, wherein the polyaspartic coating composition comprises: (A) an aspartic acid ester compound represented by the following formula (I) ##STR00008## X is an n-valent organic group obtained by removing a primary amino group of an n-valent polyamine, and R.sub.1 and R.sub.2 are the same or different organic groups which are inert to the isocyanate group under a reaction condition, and n is an integer of 2 or more, and (B) a polyisocyanate component obtained by reacting one or two or more diisocyanate monomers selected from the group consisting of an aliphatic and alicyclic diisocyanate with a polycaprolactone polyol having a number-average molecular weight of 500 to 1,500, wherein a ratio of the polycaprolactone polyol to a total amount of the polyol is 20% by mass or more, and the polyisocyanate component contains 2.7% by mass or more and 10.0% by mass or less of an isocyanurate trimer with respect to a total amount of the polyisocyanate component.

8. The method according to claim 4, wherein the diisocyanate monomer contains a hexamethylene diisocyanate.

9. A method for preventing corrosion of a structure, comprising: coating the structure with a polyaspartic coating composition comprising: (A) an aspartic acid ester compound represented by the following formula (I) ##STR00009## X is an n-valent organic group obtained by removing a primary amino group of an n-valent polyamine, and R.sub.1 and R.sub.2 are the same or different organic groups which are inert to the isocyanate group under a reaction condition, and n is an integer of 2 or more, and (B) a polyisocyanate component obtained by reacting one or two or more diisocyanate monomers selected from the group consisting of an aliphatic and alicyclic diisocyanate with a polycaprolactone polyol having a number-average molecular weight of 500 to 1,500, wherein a ratio of the polycaprolactone polyol to a total amount of the polyol is 20% by mass or more, the polyisocyanate component contains 10.0% by mass or less of an isocyanurate trimer with respect to a total amount of the polyisocyanate component, and the polyol further contains a polyoxyalkylene polyol.

10. The method according to claim 9, wherein a ratio of the polyoxyalkylene polyol to a total amount of the polyoxyalkylene polyol and the polycaprolactone polyol is 80% by mass or less.

11. The method according to claim 9, wherein an equivalent ratio between the amino group of (A) the aspartic acid ester compound and the isocyanate group of (B) the polyisocyanate component is amino group:isocyanate group=10:1 to 1:10.

12. The method according to claim 9, wherein the diisocyanate monomer contains a hexamethylene diisocyanate.

13. The method for preventing corrosion of a structure according to claim 1, wherein a number-average molecular weight of the polyisocyanate component is 1,350 to 2,000.

14. The method for preventing corrosion of a structure according to claim 7, wherein a number-average molecular weight of the polyisocyanate component is 1,350 to 2,000.

15. The method for preventing corrosion of a structure according to claim 9, wherein a number-average molecular weight of the polyisocyanate component is 1,350 to 2,000.

16. A method for preventing corrosion of a structure, comprising: coating the structure with a polyaspartic coating composition, comprising: (A) an aspartic acid ester compound represented by the following formula (I) ##STR00010## wherein X is an n-valent organic group obtained by removing a primary amino group of an n-valent polyamine, and R.sub.1 and R.sub.2 are the same or different organic groups which are inert to the isocyanate group under a reaction condition, and n is an integer of 2 or more, and (B) a polyisocyanate component obtained by reacting one or two or more diisocyanate monomers selected from the group consisting of an aliphatic and alicyclic diisocyanate with a polycaprolactone polyol having a number-average molecular weight of 500 to 1,500, wherein a ratio of the polycaprolactone polyol to a total amount of the polyol is 20% by mass or more, the structure is a bridge, a highway, a power transmission tower, or a wind power generation blade, and the polyisocyanate component contains 2.7% by mass or more and 10.0% by mass or less of an isocyanurate trimer with respect to a total amount of the polyisocyanate component.

17. The method for preventing corrosion of a structure according to claim 9, wherein the polyisocyanate component contains 2.7% by mass or more and 10.0% by mass or less of an isocyanurate trimer with respect to a total amount of the polyisocyanate component.

Description

EXAMPLES

(1) Hereinafter, the present embodiment will be described in more detail by using the Examples. However, the present embodiment is not limited to the Examples. The measurement of the various physical properties and various evaluation methods are demonstrated below. In addition, “part” and “%” refer to “part by mass” and “% by mass”, unless otherwise specified.

(2) (Physical Property 1) NCO Content (% by Mass)

(3) The NCO content (isocyanate content, % by mass) of a polyisocyanate was measured as follows. First, 1 to 3 g (Wg) of a polyisocyanate prepared in a Production Example was precisely weighed into an Erlenmeyer flask, 20 mL of toluene was added, and the polyisocyanate was completely dissolved. Thereafter, 10 mL of a solution of 2N di-n-butylamine in toluene was added and completely mixed, and then the mixture was allowed to stand for 15 minutes at room temperature. Moreover, 70 mL of isopropyl alcohol was added to this solution and completely mixed. This solution was then titrated with IN hydrochloric acid solution (factor F) using an indicator, and thus a titration value V.sub.2 mL was obtained. The same titration operation was performed without polyisocyanate, and a titration value V.sub.1 mL was obtained. The NCO content of the polyisocyanate was calculated from the resulting titration value V.sub.2 mL and the titration value V.sub.1 mL based on the following equation:
NCO content=(V.sub.1−V.sub.2)×F×42/(W×1000)×100
(Physical Property 2) Viscosity (mPa.Math.s)

(4) The viscosity of the polyisocyanate was measured at 25° C. using an E-type viscometer (trade name: RE-85R, manufactured by Toki Sangyo Co., Ltd.). In the measurement, a standard rotor (1°34′×R24) was used. The rotation speed was set as follows.

(5) 100 r.p.m. (in the case of less than 128 mPa.Math.s)

(6) 50 r.p.m. (in the case of 128 mPa.Math.s or more and less than 256 mPa.Math.s)

(7) 20 r.p.m. (in the case of 256 mPa.Math.s or more and less than 640 mPa.Math.s)

(8) 10 r.p.m. (in the case of 640 mPa.Math.s or more and less than 1,280 mPa.Math.s)

(9) 5 r.p.m. (in the case of 1,280 mPa.Math.s or more and less than 2,560 mPa.Math.s)

(10) 2.5 r.p.m. (in the case of 2,560mPa.Math.s or more and less than 5,184 mPa.Math.s)

(11) 1.0 r.p.m. (in the case of 5,184 mPa.Math.s or more and less than 12,960 mPa.Math.s)

(12) 0.5 r.p.m. (in the case of 12,960 mPa.Math.s or more and less than 25,920 mPa.Math.s)

(13) (Physical Property 3) Number-Average Molecular Weight

(14) The number-average molecular weight of the polyisocyanate was determined as a number-average molecular weight in terms of polystyrene by gel permeation chromatography (hereinafter abbreviated as “GPC”) using the following device.

(15) Device: “HLC-8120GPC” (trade name) manufactured by Tosoh Corporation

(16) Column: “TSKgel Super H1000” (trade name)×1, “TSKgel Super H2000” (product name)×1, “TSKgel Super H 3000” (product name)×1, manufactured by Tosoh Corporation

(17) Carrier: Tetrahydrofuran

(18) Detection method: Differential refractometer

(19) (Physical Property 4) Average Number of Isocyanate Groups

(20) The average number of isocyanate groups of the polyisocyanate was calculated from the NCO content (physical property 1) and the number-average molecular weight (physical property 3) based on the following equation.
Average number of isocyanate groups=number-average molecular weight×NCO content/100/42
(Physical Property 5) Mass Concentration of Diisocyanate Monomer (% by Mass)

(21) The diisocyanate mass concentration of the polyisocyanate was determined as follows. First, a 20 mL sample bottle was placed on a digital balance scale, and approximately 1 g of the sample was precisely weighed. Next, 0.03 to 0.04 g of nitrobenzene (internal standard solution) was added and precisely weighed. Finally, after adding about 9 mL of ethyl acetate, the lid was tightly closed and the sample was mixed well. The prepared sample was analyzed and quantified by gas chromatography under the following conditions.

(22) Device: “GC-8A” manufactured by SHIMADZU Corporation

(23) Column: “Silicone OV-17” manufactured by Shinwa Chemical Industries Ltd.

(24) Column oven temperature: 120° C.

(25) Injection/detector temperature: 160° C.

(26) (Physical Property 6) Polycaprolactone Polyol Ratio

(27) The ratio of the polycaprolactone polyol to the total amount of polyol was calculated from the charged amounts of the polycaprolactone polyol and the entire polyol based on the following equation.

(28) Polycaprolactone polyol ratio=charged amount of polycaprolactone polyol/total amount of charged polyol x 100

(29) (Physical Property 7) Polyoxyalkylene Polyol Ratio

(30) The polyoxyalkylene polyol ratio was calculated from the charged amounts of the polycaprolactone polyol and the polyoxyalkylene polyol based on the following equation.

(31) Polyoxyalkylene polyol ratio=charged amount of polyoxyalkylene polyol/(charged amount of polycaprolactone polyol+charged amount of polyoxyalkylene polyol)×100

(32) (Physical Property 8) Content of Isocyanurate Trimer

(33) The content of the isocyanurate trimer was quantified by GPC measurement shown in the number-average molecular weight (physical property 3). The peak area % corresponding to a molecular weight three times that of the diisocyanate used as a raw material was taken as the content of the isocyanurate trimer.

(34) (Evaluation 1) Drying Property

(35) “Desmophen 1420” (aspartic acid ester compound, trade name, manufactured by Covestro, amine value: 201 mg KOH/resin (g)) and “Desmophen 1520” (aspartic acid ester compound, trade name, manufactured by Covestro, amine value: 191 mg KOH/resin (g)) were pre-blended at a weight ratio of 1/1. The blended aspartic acid ester compounds and a polyisocyanate component were then blended so that NCO/NH=1.1, and adjusted with n-butyl acetate so that the solid content of the coating composition =80% by mass to obtain a polyaspartic coating composition. The obtained polyaspartic coating composition was coated to a glass plate with an applicator so that the dried film thickness was 80 to 100 μm, followed by drying at 23° C. The tack-free time was investigated and the drying property was evaluated according to the following criteria.

(36) ⊚: less than 90 minutes

(37) ∘: 90 minutes or more and less than 120 minutes

(38) Δ: 120 minutes or more and less than 180 minutes

(39) ×: 180 minutes or more

(40) (Evaluation 2) Scratch Resistance

(41) A commercially available solvent type two-pack acrylic urethane white enamel paint was spray-coated on an aluminum plate in advance and baked for 2 hours at 80° C., and then aged at room temperature for 2 weeks or more. Thereafter, a white plate whose surface was polished with #1000 sandpaper until the gloss value at 60° reached 10% or less was prepared as a base material. A polyaspartic coating composition obtained in the same manner as in (Evaluation 1) was coated on the white plate with an applicator so that the dried film thickness was 80 to 100 μm and dried at 23° C. for 7 days, thereby obtaining a cured coating film. The scratch resistance test was performed on the obtained coating film using a rubbing tester (manufactured by Taisei Rika Kogyo Co. LTD) by the following method.

(42) The 20° gloss value of the coated surface was measured in advance. About 1 g of polishing agent prepared by mixing a cleanser (trade name: Marzen Cleanser, manufactured by Maruzen Cleanser, Inc.) and water at a ratio of 3:2 was applied to the rubbing tester sponge, and the coating film of the test plate was rubbed back and forth 20 times under a load of 200 g. The coated surface was washed with running water, and after natural drying, the 20° gloss value of the coated surface was measured. The retention rate of the 20° gloss value was calculated based on the following equation, and the scratch resistance was evaluated according to the following criteria.
Retention rate of 20° gloss value=(20° gloss value after test/20° gloss value before test)×100

(43) If the retention rate of the 20° gloss value is 90% or more, it was evaluated as “⊚”, if less than 90% to 80% or more, it was evaluated as “∘”, if less than 80% to 50% or more, it was evaluated as “Δ”, and if less than 50%, it was evaluated as “×”.

(44) ⊚: 90% or more of gloss retention rate

(45) ∘: 80% or more and less than 90% of gloss retention rate

(46) Δ: 50% or more and less than 80% of gloss retention rate

(47) ×: less than 50% of gloss retention rate

(48) (Evaluation 3) Weather Resistance

(49) A polyaspartic coating composition obtained in the same manner as in (Evaluation 1) was coated on a white plate with an applicator so that the dried film thickness was 80 to 100 μm and dried at 23° C. for 7 days, thereby obtaining a cured coating film. Thereafter, evaluation was performed under the conditions of JIS K5600-7-8 using Dewpanel light control weather meter FDP manufactured by Suga Test Instruments Co., Ltd.

(50) ⊚: 90% or more of gloss retention rate at 60° after exposure for 3000 hours

(51) ∘: 90% or more of gloss retention rate at 60° after exposure for 2000 hours

(52) Δ: 80% or more and less than 90% of gloss retention rate at 60° after exposure for 1800 hours

(53) ×: less than 80% of gloss retention rate at 60° after exposure for 1600 hours (Evaluation 4) Curability

(54) A polyaspartic coating composition obtained in the same manner as in (Evaluation 2) was coated on a glass plate with an applicator so that the dried film thickness was 80 to 100 μm, and then dried at 23° C. for 6 hours, thereby obtaining a cured coating film.

(55) The obtained cured coating film was peeled off from the PP plate and immersed in acetone at 23° C. for 24 hours, and then the mass value of the undissolved portion relative to the mass before immersion (gel fraction) was calculated. Thereafter, the curability was evaluated according to the evaluation criteria shown below. (Evaluation criteria)

(56) ⊚: 80% or more of gel fraction

(57) ∘: 70% or more and less than 80% of gel fraction

(58) Δ: 60% or more and less than 70% of gel fraction

(59) ×: less than 60% of gel fraction

(60) (Evaluation 5) Chemical Resistance

(61) A polyaspartic coating composition obtained in the same manner as in (Evaluation 2) was coated on a glass plate with an applicator so that the dried film thickness was 80 to 100 μm, followed by drying at 23° C. for 7 days to obtain a cured coating film.

(62) Subsequently, “Skydrol 500B-4” (phosphate ester-based flame retardant hydraulic fluid for aircraft, trade name, manufactured by EASTMAN) was dropped on the obtained cured coating film, and allowed to stand at 23° C. for 24 hours. Subsequently, the appearance change of the coating film after 24 hours was observed. Subsequently, chemical resistance was evaluated according to the evaluation criteria shown below.

(63) (Evaluation Criteria)

(64) ∘: No change in appearance of coating film

(65) Δ: slight change in appearance of coating film

(66) ×: change in appearance of coating film

Production Example 1-1

(67) The inside of a four-necked flask equipped with a stirrer, thermometer, reflux condenser, nitrogen blow-in pipe and dropping funnel was made into a nitrogen atmosphere, and 100 parts of HDI was charged thereto, and the temperature inside the reactor was kept at 60° C. while stirring. 0.15 parts of a solution prepared by diluting an isocyanuration reaction catalyst of tetrabutylammonium acetate with 2-ethyl-1-hexanol to 10% by mass was added to carry out an isocyanuration reaction, and phosphoric acid was added at the time when the NCO content of the reaction solution reached 43.8% by mass to stop the reaction. Thereafter, the reaction solution was kept at 90° C. for 1 hour. The cooled reaction solution was filtered and then the unreacted HDI was removed using a thin film evaporator. A polyisocyanate P1-1 having an NCO content of 23.1% by mass, a viscosity at 25° C. of 1,350 mPa.Math.s, a number-average molecular weight of 590, an isocyanate group average number of 3.2, an HDI monomer mass concentration of 0.1% by mass, and an isocyanurate trimer content of 65.2% by mass was obtained.

Production Example 1-2

(68) The inside of a four-necked flask equipped with a stirrer, thermometer, reflux condenser, nitrogen blow-in pipe and dropping funnel was made into a nitrogen atmosphere, and 100 parts of HDI and 33.7 parts of polycaprolactone triol having a number-average molecular weight of 850 were charged thereto, and the temperature inside the reactor was kept at 95° C. for 90 minutes while stirring to carry out the urethanization reaction. The cooled reaction solution was filtered and then the unreacted HDI was removed using a thin film evaporator. A polyisocyanate P1-2 having an NCO content of 9.0% by mass, a viscosity at 25° C. of 4,980 mPa.Math.s, a number-average molecular weight of 1,520, an isocyanate group average number of 3.3, an HDI monomer mass concentration of 0.2% by mass, and an isocyanurate trimer content of 0.0% by mass was obtained.

Production Example 1-3

(69) The inside of a four-necked flask equipped with a stirrer, thermometer, reflux condenser, nitrogen blow-in pipe and dropping funnel was made into a nitrogen atmosphere, and 100 parts of HDI, 6.9 parts of polycaprolactone triol having a number-average molecular weight of 550 and 12.8 parts of polytetramethylene glycol having a number-average molecular weight of 1,000 were charged thereto, and the temperature inside the reactor was kept at 90° C. for 1 hour while stirring to carry out the urethanization reaction. The cooled reaction solution was filtered and then the unreacted HDI was removed using a thin film evaporator. A polyisocyanate P1-3 having an NCO content of 8.9% by mass, a viscosity at 25° C. of 2,740 mPa.Math.s, a number-average molecular weight of 1,570, an isocyanate group average number of 3.3, an HDI monomer mass concentration of 0.2% by mass, and an isocyanurate trimer content of 0.0% by mass was obtained.

Production Example 1-4

(70) The inside of a four-necked flask equipped with a stirrer, thermometer, reflux condenser and nitrogen blow-in pipe was made into a nitrogen atmosphere, and 100 parts of the polyisocyanate P1-1 and 8 parts of polycaprolactone diol having a number-average molecular weight of 500 were charged thereto, and the temperature inside the reactor was kept at 80° C. for 1 hour while stirring to carry out the urethanization reaction. A polyisocyanate P1-4 having an NCO content of 10.9% by mass, a viscosity at 25° C. of 4,610 mPa.Math.s, a number-average molecular weight of 1,330, an isocyanate group average number of 3.5, an HDI monomer mass concentration of 0.2% by mass, and an isocyanurate trimer content of 11.7% by mass was obtained.

Production Example 1-5

(71) The inside of a four-necked flask equipped with a stirrer, thermometer, reflux condenser, nitrogen blow-in pipe and dropping funnel was made into a nitrogen atmosphere, and 100 parts of HDI and 78.5 parts of polypropylene glycol having a number-average molecular weight of 2,000 were charged thereto, and the temperature inside the reactor was kept at 100° C. for 1 hour while stirring to carry out a urethanization reaction. 0.025 parts of a solution prepared by diluting an allophanatization catalyst of 2-zirconium ethylhexanoate with 2-ethyl-1-hexanol to 20% by mass was added thereto to carry out an isocyanuration reaction, and phosphoric acid was added at the time when the refractive index of the reaction solution increased to 0.0052 to stop the reaction. Thereafter, the reaction solution was kept at 130° C. for 1 hour. The cooled reaction solution was filtered and then the unreacted HDI was removed using a thin film evaporator. A polyisocyanate P1-5 having an NCO content of 6.0% by mass, a viscosity at 25° C. of 2,150 mPa.Math.s, a number-average molecular weight of 2,870, an isocyanate group average number of 4.1, a reacted HDI mass concentration of 0.1% by mass, and an isocyanurate trimer content of 3.0% by mass was obtained.

(72) TABLE-US-00001 TABLE 1 Production Production Production Production Production Example Example Example Example Example 1-1 1-2 1-3 1-4 1-5 Polyisocyanate P1-1 P1-2 P1-3 P1-4 P1-5 (Physical Property 1) 23.1 9.0 8.9 10.9 6.0 NCO Content[% by mass] (Physical Property 2) 1,350 4,980 2,740 4,610 2,150 Viscosity[mPa .Math. s/25° C.] (Physical Property 3) 590 1,520 1,570 1,330 2,870 Number-Average Molecular Weight (Physical Property 4) 3.2 3.3 3.3 3.5 4.1 Average Number of Isocyanate Groups (Physical Property 5) 0.1 0.2 0.2 0.2 0.1 Diisocyanate Monomer Mass Concentration [% by mass] (Physical Property 6) — 100.0 35.0 100.0 0.0 Polycaprolactone Polyol Ratio [% by mass] (Physical Property 7) — 0.0 65.0 0.0 100.0 Polyoxyalkylene Polyol Ratio [% by mass] (Physical Property 8) 65.2 0.0 0.0 11.7 3.0 Isocyanurate Trimer Mass Concentration [% by mass]

Example 1-1

(73) The inside of a four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen blow-in tube was made into a nitrogen atmosphere, 18 parts of the polyisocyanate P1-1 and 132 parts of the polyisocyanate P1-2 were charged thereto and stirred until it became uniform to obtain a polyisocyanate component. The results of the physical properties of the obtained polyisocyanate component are shown in Table 2. The drying property and chemical resistance of the aspartic acid ester compound were also evaluated. The results are shown in Table 2.

Examples 1-2 to 1-9, Comparative Examples 1-1 to 1-4

(74) A polyisocyanate component was obtained in the same manner as in Example 1-1 except that the compositions were as shown in Table 2. The results of the physical properties of the obtained polyisocyanate are shown in Table 2. The dryness and chemical resistance of the aspartic acid esters were also evaluated. The results are shown in Table 2.

(75) TABLE-US-00002 TABLE 2 Comp. Comp. Comp. Comp. Ex. Ex. Ex. Ex. Ex. Ex. Ex. Ex. Ex. Ex. Ex. Ex. Ex. 1-1 1-2 1-3 1-4 1-5 1-6 1-7 1-8 1-9 1-1 1-2 1-3 1-4 (A) Aspartic Desmophen 50 50 50 50 50 50 50 50 50 50 50 50 50 Acid Ester NH1420 Compound [mass by part] Desmophen 50 50 50 50 50 50 50 50 50 50 50 50 50 NH1520 [mass by part] (B) Polyisocyanate P-1 [mass by part] 18 13 7 — 22 16 8 — — 23 28 — — Component P-2 [mass by part] 132 147 161 180 — — — — 90 121 — — — P-3 [mass by part] — — — — 124 140 160 180 90 — 111 — — P-4 [mass by part] — — — — — — — — — — — 148 — P-5 [mass by part] — — — — — — — — — — — — 268 (Physical Property 1) 10.7 10.1 9.6 9.0 11.0 10.4 9.6 8.9 9.0 11.3 11.8 10.9 6.0 NCO Content [% by mass] (Physical Property 2) 4,260 4,490 4,730 4,980 2,470 2,560 2,650 2,740 3,690 4,050 2,380 4,610 2,150 Viscosity [mPa .Math. s/25° C.] (Physical Property 3) 1,310 1,380 1,450 1,520 1,260 1,350 1,460 1,570 1,550 1,240 1,170 1,330 2,870 Number-average Molecular Weight (Physical Property 4) 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.5 4.1 Average Number of Isocyanate Groups (Physical Property 5) 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.1 Diisocyanate Monomer Mass Concen- tration [% by mass] (Physical Property 7) 0.0 0.0 0.0 0.0 65.0 65.0 65.0 65.0 24.0 0.0 65.0 0.0 100.0 Polyoxyalkylene Polyol Ratio [% by mass] (Physical Property 8) 7.8 5.3 2.7 0.0 9.8 6.7 3.1 0.0 0.0 10.4 13.1 11.7 3.0 lsocyanurate Trimer Mass Concen- tration [% by mass] Compounding Molar Ratio 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1 Ratio of NCO/NH Solvent n-Butyl Acetate 62 65 67 70 61 64 67 70 70 61 60 62 92 [mass by part] (Evaluation 1) Drying Property ⊚ ◯ ◯ Δ ⊚ ◯ ◯ Δ Δ ⊚ ⊚ ⊚ X (Evaluation 2) Scratch Property ◯ ◯ ◯ ⊚ Δ ◯ ◯ ⊚ ⊚ X X X ⊚ (Evaluation 3) Weather Resistance Δ ◯ ◯ ⊚ Δ ◯ ◯ ◯ ⊚ Δ Δ Δ X

(76) As shown in the above results, it was possible to obtain a coating film having excellent scratch resistance and excellent weather resistance while maintaining the drying property by using the polyaspartic coating compositions containing an aliphatic polyisocyanate component of the Examples.

Production Example 2-1

Production of P2-1

(77) The inside of a four-necked flask equipped with a stirrer, a thermometer, a reflux condenser, a nitrogen blowing pipe and a dropping funnel was made into a nitrogen atmosphere, and 100 parts of HDI and 5.0 parts of polycaprolactone triol having a number-average molecular weight of 300 were charged thereto. Then, the temperature inside the reactor was kept at 90° C. for 1 hour while stirring to carry out a urethanization reaction. Next, the temperature inside the reactor was lowered and kept at 80° C., and an isocyanuration reaction catalyst of tetramethylammonium capriate was added to carry out an isocyanuration reaction. Then, phosphoric acid was added at the time when the refractive index of the reaction solution increased to 0.0172 to stop the reaction. Then, the temperature inside the reactor was raised and kept at 90° C. for 1 hour. Then, the reaction solution was cooled and filtered, and then the unreacted HDI was removed using a thin film evaporator to obtain a polyisocyanate P2-1. The obtained P2-1 had an NCO content of 18.2% by mass, a viscosity at 25° C. of 21,310 mPa.Math.s, a number-average molecular weight of 1,240, an isocyanate group average number of 5.4, and an HDI monomer mass concentration of 0.1% by mass. The above physical properties are also shown in Table 3.

Production Example 2-2

Production of P2-2

(78) The inside of a four-necked flask equipped with a stirrer, a thermometer, a reflux condenser, a nitrogen blowing pipe and a dropping funnel was made into a nitrogen atmosphere, and 100 parts of HDI and 4.0 parts of 1,3-butanediol were charged thereto. Then, the temperature inside the reactor was kept at 90° C. for 1 hour while stirring to carry out a urethanization reaction. Next, the temperature inside the reactor was lowered and kept at 80° C., and an isocyanuration reaction catalyst of tetramethylammonium capriate was added to carry out an isocyanuration reaction. Then, phosphoric acid was added at the time when the yield reached 55% to stop the reaction. Then, the temperature inside the reactor was raised and kept at 90° C. for 1 hour. Then, the reaction solution was cooled and filtered, and the unreacted HDI was removed using a thin film evaporator to obtain a polyisocyanate P2-2. The obtained P2-2 had an NCO content of 19.1% by mass, a viscosity at 25° C. of 13,760 mPa.Math.s, a number-average molecular weight of 1,040, an isocyanate group average number of 4.7, and an HDI monomer mass concentration of 0.1% by mass. The above physical properties are shown in Table 3.

Production Example 2-3

Production of P2-3

(79) The inside of a four-necked flask equipped with a stirrer, a thermometer, a reflux condenser, a nitrogen blowing pipe and a dropping funnel was made into a nitrogen atmosphere, and 100 parts of HDI and 6.3 parts of polycaprolactone triol having a number-average molecular weight of 300 were charged thereto. Next, the temperature inside the reactor was kept at 130° C. for 1 hour while stirring to carry out a urethanization reaction. Then, the temperature inside the reactor was kept at 130° C. for 1 hour while stirring to carry out a urethanization reaction. Next, 0.037 parts of a solution prepared by diluting an allophanate reaction catalyst of 2-ethylhexanoate zirconium with 2-ethyl-1-hexanol to 20% by mass was added to carry out an allophanatization reaction. Then, phosphoric acid was added at the time when the refractive index of the reaction solution increased to 0.0052 to stop the reaction. Then, the temperature inside the reactor was kept at 90° C. for 1 hour. Then, the reaction solution was cooled and filtered, and then the unreacted HDI was removed using a thin film evaporator to obtain a polyisocyanate P2-3. The obtained P2-3 had an NCO content of 17.7% by mass, a viscosity at 25° C. of 9,250 mPa.Math.s, a number-average molecular weight of 1,450, an isocyanate group average number of 6.1, and an HDI monomer mass concentration of 0.2% by mass. The above physical properties are also shown in Table 3.

Production Example 2-4

Production of P2-4

(80) The inside of a four-necked flask equipped with a stirrer, a thermometer, a reflux condenser, a nitrogen blowing pipe and a dropping funnel was made into a nitrogen atmosphere, and 100 parts of HDI and 17.0 parts of polycaprolactone triol having a number-average molecular weight of 850 were charged thereto. Next, the temperature inside the reactor was kept at 130° C. for 1 hour while stirring to carry out a urethanization reaction. Next, 0.037 parts of a solution prepared by diluting an allophanate reaction catalyst of 2-ethylhexanoate zirconium with 2-ethyl-1-hexanol to 20% by mass was added to carry out an allophanatization reaction. Then, phosphoric acid was added at the time when the refractive index of the reaction solution increased to 0.0052 to stop the reaction. Then, the temperature inside the reactor was kept at 130° C. for 1 hour. Then, the reaction solution was cooled and filtered, and then the unreacted HDI was removed using a thin film evaporator to obtain a polyisocyanate P2-4. The obtained P2-4 had an NCO content of 13.2% by mass, a viscosity at 25° C. of 8,010 mPa.Math.s, a number-average molecular weight of 1,970, an isocyanate group average number of 6.2, and an HDI monomer mass concentration of 0.2% by mass. The above physical properties are also shown in Table 3.

Production Example 2-5

Production of P2-5

(81) The inside of a four-necked flask equipped with a stirrer, a thermometer, a reflux condenser, a nitrogen blowing pipe and a dropping funnel was made into a nitrogen atmosphere, and 100 parts of HDI and 15.5 parts of polycaprolactone diol having a number-average molecular weight of 500 were charged thereto. Next, the temperature inside the reactor was kept at 130° C. for 1 hour while stirring to carry out a urethanization reaction. Next, 0.037 parts of a solution prepared by diluting an allophanate reaction catalyst of 2-ethylhexanoate zirconium with 2-ethyl-1-hexanol to 20% by mass was added to carry out an allophanatization reaction. Then, phosphoric acid was added at the time when the refractive index of the reaction solution increased to 0.0052 to stop the reaction. Then, the temperature inside the reactor was kept at 130° C. for 1 hour. Then, the reaction solution was cooled and filtered, and then the unreacted HDI was removed using a thin film evaporator to obtain a polyisocyanate P2-5. The obtained P2-5 had an NCO content of 14.0% by mass, a viscosity at 25° C. of 4,870 mPa.Math.s, a number-average molecular weight of 1,260, an isocyanate group average number of 4.2, and an HDI monomer mass concentration of 0.2% by mass. The above physical properties are also shown in Table 3.

Production Example 2-6

Production of P2-6

(82) The inside of a four-necked flask equipped with a stirrer, a thermometer, a reflux condenser, a nitrogen blowing pipe and a dropping funnel was made into a nitrogen atmosphere, and 100 parts of HDI was charged thereto. Next, the temperature inside the reactor was kept at 60° C. while stirring. Next, 0.15 parts of a solution prepared by diluting an isocyanuration reaction catalyst of tetrabutylammonium acetate with 2-ethyl-1-hexanol to 10% by mass was added to carry out an isocyanuration reaction. Then, phosphoric acid was added at the time when the NCO content of the reaction solution reached 43.8% by mass to stop the reaction. Then, the temperature inside the reactor was kept at 90° C. for 1 hour. Then, the reaction solution was cooled and filtered, and then the unreacted HDI was removed using a thin film evaporator to obtain a polyisocyanate P2-6. The obtained P2-6 had an NCO content of 23.1% by mass, a viscosity at 25° C. of 1,350 mPa.Math.s, a number-average molecular weight of 590, an isocyanate group average number of 3.2, and an HDI monomer mass concentration of 0.1% by mass. The above physical properties are also shown in Table 3.

(83) TABLE-US-00003 TABLE 3 Production Production Production Production Production Production Example Example Example Example Example Example 2-1 2-2 2-3 2-4 2-5 2-6 Polyisocyanate P2-1 P2-2 P2-3 P2-4 P2-5 P2-6 (Physical Property 1) 18.2 19.1 17.7 13.2 14.0 23.1 NCO Content [% by mass] (Physical Property 2) 21,310 13,760 9,250 8,010 4,870 1,350 Viscosity [mPa .Math. s/25° C.] (Physical Property 3) 1,240 1,040 1,450 1,970 1,260 590 Number-average Molecular Weight (Physical Property 4) 5.4 4.7 6.1 6.2 4.2 3.2 Average Number of Isocyanate Groups (Physical Property 5) 0.1 0.1 0.2 0.2 0.2 0.1 Diisocyanate Monomer Mass Concentration [% by mass]

Example 2-1

(84) 1. Preparation of polyisocyanate component B′-1

(85) The inside of a four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen blow-in tube was made into a nitrogen atmosphere, 88 parts of the polyisocyanate P2-1 was charged thereto and stirred until it became uniform to obtain a polyisocyanate component B′-1. The physical properties of the obtained polyisocyanate component are B′-1 shown in Table 4. 2. Production of polyaspartic coating composition 1

(86) “Desmophen 1420” (aspartic acid ester compound, trade name, manufactured by Covestro, amine value: 201 mg KOH/resin (g)) and “Desmophen 1520” (aspartic acid ester compound, trade name, manufactured by Covestro, amine value: 191 mg KOH/resin (g)) were pre-blended at a mass ratio of 1/1. The blended aspartic acid ester compounds and a polyisocyanate component B′-1 were then blended so that NCO/NH=1.1, and then adjusted with n-butyl acetate so that the solid content of the coating composition=80% by mass to obtain the polyaspartic coating composition 1. The obtained polyaspartic coating composition 1 was used to prepare a coating film and the evaluations 1 to 3 were performed. The results are shown in Table 4.

Examples 2-2 to 2-10, Comparative Examples 2-1 to 2-4

(87) 1. Preparation of polyisocyanate components B′-2 to B′-10 and B′-11 to B′-14

(88) Polyisocyanate components B′-2 to B′-10 and B′-11 to B′-14 were obtained in the same manner as in “1.” of Example 2-1 except that the compositions were as shown in Tables 2 and 3. The physical properties of the obtained polyisocyanate components B′-2 to B′-10 and B′-11 to B′-14 are shown in Tables 4 and 5. 2. Production of polyaspartic coating compositions 2 to 10 and 11 to 14

(89) Subsequently, polyaspartic coating compositions 2 to 10 and 11 to 14 were obtained in the same manner as in “2.” of Example 2-1 except that the compositions were as shown in Tables 2 and 3. The obtained polyaspartic coating compositions 2 to 10 and 11 to 14 were used to prepare coating films, and the evaluations 1 to 3 were performed. The results are shown in Tables 4 and 5.

(90) TABLE-US-00004 TABLE 4 Example 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 2-10 (A) Aspartic Acid Desmophen NH1420 50 50 50 50 50 50 50 50 50 50 ester Compound [mass by part] Desmophen NH1520 50 50 50 50 50 50 50 50 50 50 [mass by part] (B′) Polyisocyanate P2-1 [mass by part] 88 63 39 — — — — — — — Component P2-2 [mass by part] — — — 84 30 — — — — — P2-3 [mass by part] — — — — — 91 15 — — — P2-4 [mass by part] — — — — — — — 122 24 — P2-5 [mass by part] — — — — — — — — — 116 P2-6 [mass by part] — 21 39 — 45 — 58 — 56 — (Physical Property 1) 18.2 19.4 20.7 19.1 21.5 17.7 22.0 13.2 20.1 14.0 NCO Content [% by mass] (Physical Property 2) 21,310 10,580 5,260 13,760 3,460 9,250 2,020 8,010 2,270 4,870 Viscosity [mPa .Math. s/25° C.] (Physical Property 3) 1,240 1,050 870 1,040 750 1,450 720 1,970 850 1,260 Number-average Molecular Weight (Physical Property 4) 5.4 4.9 4.3 4.7 3.8 6.1 3.8 6.2 4.1 4.2 Average Number of Isocyanate Groups (Physical Property 5) 0.1 0.1 0.1 0.1 0.1 0.2 0.1 0.2 0.1 0.2 Diisocyanate Monomer Mass Concentration [% by mass] Compounding Ratio Molar Ratio of NCO/NH 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1 Solvent n-Butyl Acetate 47 46 45 46 44 48 43 56 45 54 [mass by part] (Evaluation 4) Curability ⊚ ⊚ ◯ ⊚ ◯ ⊚ ◯ ⊚ ◯ ◯ (Evaluation 5) Chemical Resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ (Evaluation 3) Weather Resistance ◯ ◯ ◯ ◯ Δ ◯ Δ ◯ ◯ ◯

(91) TABLE-US-00005 TABLE 5 Comp. Comp. Comp. Comp. Ex. Ex. Ex. Ex. 2-1 2-2 2-3 2-4 (A)Aspartic Acid ester Desmophen NH1420 50 50 50 50 Compound [mass by part] Desmophen NH1520 50 50 50 50 [mass by part] (B′)Polyisocyanate P2-1[mass by part] — — — — Component P2-2[mass by part] 18 — — — P2-3[mass by part] — 7 — — P2-4[mass by part] — — — — P2-5[mass by part] — — 24 — P2-6[mass by part] 55 65 56 70 (Physical Property 1) 22.1 22.6 20.4 23.1 NCO Content[% by mass] (Physical Property 2) 2,450 1,670 1,960 1,350 Viscosity[mPa .Math. s/25° C.] (Physical Property 3) 650 630 710 590 Number-average Molecular Weight (Physical Property 4) 3.4 3.4 3.4 3.2 Average Number of Isocyanate Groups (Physical Property 5) 0.1 0.1 0.1 0.1 Diisocyanate Monomer Mass Concentration[% by mass] Compounding Ratio Molar Ratio of NCO/NH 1.1 1.1 1.1 1.1 Solvent n-Butyl Acetate [mass by part] 43 43 45 42 (Evaluation 4)Curability Δ Δ Δ X (Evaluation 5)Chemical Resistance Δ Δ Δ X (Evaluation 3)Weather Resistance X X X X

(92) As shown in Table 4, the coating films using the polyaspartic coating compositions of Examples 2-1 to 2-10 containing (A) an aspartic acid ester and (B) a polyisocyanate component and having an average number of isocyanate groups of 3.8 to 6.2 had excellent curability and chemical resistance.

(93) In addition, the coating films using the polyaspartic coating compositions of Examples 2-1, 2-2, 2-4, 2-6 and 2-8 having an average number of isocyanate groups of 4.7 or more had particularly excellent curability.

(94) Moreover, the coating films using the polyaspartic coating compositions of Examples 2-1 to 2-4, 2-6, and 2-8 to 2-10 having an average number of isocyanate groups of 4.1 or more had particularly excellent weather resistance.

(95) On the other hand, as shown in Table 5, the coating films using the polyaspartic coating compositions of Comparative Examples 1 to 4 containing (A) an aspartic acid ester compound and (B) a polyisocyanate component and having an average number of isocyanate groups of 3.2 to 3.4 had inferior curability, chemical resistance and weather resistance.

(96) In addition, the coating film using the polyaspartic coating composition of Comparative Example 4 having an average number of isocyanate groups of 3.2 had particularly inferior curability, chemical resistance and weather resistance.

(97) From the above, it was confirmed that a coating film having excellent curability, weather resistance and chemical resistance can be obtained by using the polyaspartic coating composition of the present embodiment.

INDUSTRIAL APPLICABILITY

(98) The polyaspartic coating composition of the present invention can be suitably used as a primer or an intermediate or upper coating material for metals such as steel plates or surface-treated steel plates, plastics, ceramics such as inorganic materials, glass and concrete by roll coating, curtain flow coating, spray coating, electrostatic coating, bell coating, immersion, roller coating, brush coating or the like. The polyaspartic coating composition of the present invention can be suitably used to impart aesthetics, weather resistance, acid resistance, rust resistance, chipping resistance, adhesion and the like. In addition, the polyaspartic coating composition of the present invention is also useful as an adhesive, a pressure-sensitive adhesive, an elastomer, a foam, a surface treatment agent and the like.