Epoxy acrylic hybrid resins

Abstract

An aqueous dispersion comprising at least one fatty acid-modified epoxy amine adduct wherein the fatty acid has an iodine number of lower than 30 and at least one polymer obtained from the polymerization of one or more ethylenically unsaturated monomers and their use for forming coatings or binder agents, especially for decorative and protective coating applications on various substrates.

Claims

1. An aqueous dispersion comprising: at least one fatty acid-modified epoxy amine adduct ZYW.sub.S containing amino groups which are at least partially protonated, wherein the fatty acid W.sub.S of the at least one fatty acid-modified epoxy amine adduct ZYW.sub.S is a fatty acid that contains at least 8 carbon atoms and has an iodine number according to DIN 53241-1:1995-05 of lower than 30, and the fatty acid W.sub.S of the at least one fatty acid-modified epoxy amine adduct ZYW.sub.S is bound to the epoxy amine adduct through a hydroxyl ester link, and at least one polymer V obtained from the polymerization of one or more ethylenically unsaturated monomers, said at least one polymer V being hydrophobic.

2. The aqueous dispersion according to claim 1, wherein the at least one fatty acid-modified epoxy amine adduct ZYW.sub.S comprises a chain extended product (ZYW.sub.SX) obtained from the reaction of: an aqueous solution of a fatty acid-modified epoxy amine adduct ZYW.sub.S emulsion polymer, wherein at least part of the amine groups present in the fatty acid-modified epoxy amine adduct ZYW.sub.S is converted in a salt form by an acid, with at least one epoxy compound X.

3. The aqueous dispersion according to claim 2, wherein the at least one epoxide compound X has at least two epoxide groups per molecule and is selected from diglycidyl ethers of aromatic or aliphatic diols and diglycidyl esters of aromatic or aliphatic diacids.

4. The aqueous dispersion according to claim 1 wherein the dispersion is obtained by a process comprising the steps of: a) obtaining a fatty acid-modified epoxy amine adduct ZYW.sub.S by a process comprising the steps of reacting: at least one epoxide compound Z containing at least one epoxide groups, at least one amine Y containing at least one primary or secondary amino group, and at least one fatty acid W.sub.S, wherein the fatty acid contains at least 8 carbon atoms and has an iodine number according to DIN 53241-1:1995-05 lower than 30, b) adding to the fatty acid-modified epoxy amine adduct ZYW.sub.S obtained in step (a) water and at least one acid, in an amount such that the ratio acid value/amine value of the fatty acid-modified epoxy amine adduct ZYW.sub.S is at least 0.05 thereby at least partially protonating the amino groups, c) optionally reacting the adduct ZYW.sub.S obtained in step (b) with at least an epoxide compound X having at least one epoxy groups per molecule, the amount of said epoxide compound X being such that the equivalent number of amino groups in ZYW.sub.S which are reactive in respect of reaction with an epoxide group is at least equal to the equivalent number of the epoxide groups in the epoxide compound X, thereby obtaining a compound ZYW.sub.SX, and d) polymerizing one or more ethylenically unsaturated monomers in presence of the fatty acid-modified epoxide amine adduct ZYW.sub.S obtained at step (b) or in presence of the compound ZYW.sub.SX obtained at step (c), said one or more unsaturated monomers having less than 15% solubility in water, measured at 25° C. as a percentage of grams of dissolved monomers per 100 grams of water, thereby forming a hydrophobic polymer V.

5. The aqueous dispersion according to claim 4, wherein the at least one fatty acid-modified epoxy amine adduct ZYW.sub.S and/or the ZYW.sub.SX has an amine value according to DIN 53176:2002-11 of at least 50 mg KOH/g.

6. The aqueous dispersion according to claim 4, comprising from 10 to 40 wt % of the at least one fatty acid-modified epoxy amine adduct ZYW.sub.S and/or the ZYW.sub.SX, and from 60 to 90 wt % of at least one polymer V, based on the sum of the at least one fatty acid-modified epoxy amine adduct ZYW.sub.S and/or the ZYW.sub.SX and V.

7. The aqueous dispersion according to claim 1, wherein the epoxy Z of the at least one fatty acid-modified epoxy amine adduct ZYW.sub.S is an epoxide compound that has at least two epoxide groups per molecule and is selected from diglycidyl ethers of aromatic or aliphatic diols and diglycidyl esters of aromatic or aliphatic diacids.

8. The aqueous dispersion according to claim 1, wherein the amine Y of the at least one fatty acid-modified epoxy amine adduct ZYW.sub.S is an amine that is selected from aliphatic, linear, branched or cyclic amines comprising from 2 to 20 carbon atoms and comprises at least an amine Y1 comprising at least one primary amine and/or an amine Y2 comprising at least one secondary amine.

9. The aqueous dispersion according to claim 1, wherein the fatty acid W.sub.S of the at least one fatty acid-modified epoxy amine adduct ZYW.sub.S is a fatty acid that is selected from the group consisting of caprylic acid, decanoic acid, lauric acid, myristic acid, palmic acid, stearic acid, and mixtures thereof.

10. The aqueous dispersion according to claim 1, wherein the at least one polymer V is obtained from the polymerization of at least one or more (meth)acrylate monomers, styrenic monomers, (meth)acrylamide monomers, vinyl carboxylate monomers or a combination thereof.

11. The aqueous dispersion according to claim 1, wherein the at least one polymer V is obtained from a monomer mixture containing at least 15 wt % and not more than 90 wt % of monomers having a glass transition temperature Tg of their homopolymerisate of at least 50° C.

12. The aqueous dispersion according to claim 1, having a mass fraction of solid of from 10 to 60%, as determined according to DIN 55671:2002-09.

13. Process for the preparation of the aqueous dispersion according to claim 1 comprising the steps of: a) obtaining the fatty acid-modified epoxy amine adduct ZYW.sub.S by a process comprising the steps of reacting: at least one epoxide compound Z containing at least one, epoxide groups, at least one amine Y containing at least one primary or secondary amino group, and at least one fatty acid W.sub.S, wherein the fatty acid contains at least 8 carbon atoms and has an iodine number according to DIN 53241-1:1995-05 lower than 30, b) adding to the fatty acid-modified epoxy amine adduct ZYW.sub.S obtained in step (a) water and at least one acid, in an amount such that the ratio acid value/amine value of the fatty acid-modified epoxy amine adduct ZYW.sub.S is at least 0.05 thereby at least partially protonating the amino groups, c) optionally reacting the adduct ZYW.sub.S obtained in step (b) with at least an epoxide compound X having at least one, epoxy groups per molecule, the amount of said epoxide compound X being such that the equivalent number of amino groups in ZYW.sub.S which are reactive in respect of reaction with an epoxide group is at least equal to the equivalent number of the epoxide groups in the epoxide compound X, thereby obtaining a compound ZYW.sub.SX, and d) polymerizing one or more ethylenically unsaturated monomers in presence of the fatty acid-modified epoxide amine adduct ZYW.sub.S obtained at step (b) or in presence of the compound ZYW.sub.SX obtained at step (c) thereby forming the polymer V.

14. The process according to claim 13, wherein step c) is executed and wherein the amount of each of said epoxide compound X is such that the equivalent number of amino groups in ZYW.sub.S which are reactive in respect of addition reaction with an epoxide group is at least 10% greater than the equivalent number of the epoxide groups in the epoxide compound X.

15. The process according to claim 13, wherein in step b) the ratio acid value/amine value of the fatty acid-modified epoxy amine adduct ZYW.sub.S is from 0.2 to 1.0.

16. A process for preparing a coated substrate or article, comprising the step of coating at least part of the surface of the substrate or article with the aqueous dispersion according to claim 1.

17. A substrate or article having at least part of its surface coated with the aqueous dispersion according to claim 1.

Description

PREPARATION OF EMULSIFIER POLYMERS ZYW.SUB.S .(EXAMPLE 1)

(1) In a 4-necked round glass reactor 214.0 g (1.0 mole) of Coconut oil fatty acid (W.sub.S), 306.6 g (3.0 mole) of dimethylaminopropyl amine (Y1) and 105.1 g (1.0 mole) of diethanol amine (Y2) were mixed upon stirring and heated to 60° C. Then 1520 g (4.0 mole) of bisphenol-A-diglycidyl ether (BADGE; Z) were continuously added over 60 minutes to the reaction mixture. Due to the exothermic nature of the reaction, the reaction temperature gradually rose to 160° C. during the addition of the epoxide. The resulting reaction mixture was stirred for one additional hour at 160° C. Then the viscous reaction product was poured into a pre-mixed solution of 220 g aqueous formic acid (85%) in 5000 g de-ionized water and further stirred at 70° C. until a clear, transparent, brownish aqueous solution of the emulsifier polymer ZYW.sub.S was obtained. Finally, the resulting reaction product was adjusted to an overall solids content of 25.1% by the addition of de-ionized water.

PREPARATION OF EMULSIFIER POLYMERS ZYW.SUB.S.X (EXAMPLE 2)

(2) Example 1 was repeated except that before adjusting the reaction product to the overall solids content of 25.1%, an additional portion of 107.3 g (0.28 mole) bisphenol-A-diglycidyl ether (BADGE; X) was added to this aqueous solution in one shot and stirred for 3 to 5 hours at 70° C. until full conversion of the epoxide was observed by titration. A transparent, clear, brownish aqueous solution of emulsifier polymer ZYW.sub.SX was obtained as reaction product. Finally, the resulting reaction product was adjusted to an overall solids content of 25.1% by the addition of de-ionized water.

PREPARATION OF EMULSIFIER POLYMERS ZYWX (COMPARATIVE EXAMPLE 3)

(3) Example 2 was repeated except that 280.0 g (1.00 mole) of tall oil fatty acid was used instead of the 214.0 g (1.00 mole) coconut oil fatty acid.

(4) The types and amounts of reagents used to prepare polymers of examples 1 and 2 and comparative example 3 are summarized in Table 1.

(5) Characteristics of polymers of examples 1 and 2 and comparative example 3 are summarized in Table 1 and are obtained according to the test methods described in the specification.

(6) TABLE-US-00001 TABLE 1 Composition (g) of Polymers 1, 2 and Comparative Polymer 3: Component Example 1 Example 2 Comp. Example 3 Coconut oil fatty acid  214.0 g (1.0 mole)  214.0 g (1.00 mole) — (Ws) Tall oil fatty acid (W) — —  280.0 g (1.00 mole) Dimethylaminopropyl  306.6 g (3.0 mole)  306.6 g (3.00 mole)  306.6 g (3.00 mole) amine (Y1) Diethanol amine (Y2)  105.1 g (1.0 mole)  105.1 g (1.00 mole)  105.1 g (1.00 mole) BADGE (Z) 1520.0 g (4.00 mole) 1520.0 g (4.00 mole) 1520.0 g (4.00 mole) Deionized H.sub.2O (in 6183 g 6500 g 6700 g total) Aqueous formic acid  220 g (4.06 mole)  220 g (4.06 mole)  220 g (4.06 mole) (85%) BADGE (X) —  107.3 g (0.28 mole)  107.3 g (0.28 mole) Solids content %  25.1%  25.1%  25.1% Amine value 183 174 170 (mg KOH/g solids) Acid value (mg 108  94  93 KOH/g solids) pH  5.4  5.4  5.3

(7) The types and amounts of reagents used to prepare final dispersions of examples 4 and 5 and comparative example 6 are summarized in Table 2.

PREPARATION OF FINAL DISPERSIONS ZYW.SUB.S.V (EXAMPLE 4)

(8) 1505 g of Emulsifier Polymer solution obtained as reaction product of Example 1 and 660 g of de-ionized water were added to a 4-necked round glass reactor and heated to 65° C. upon stirring. Then 7.2 g of 2,2′-Azobis(2-amidinopropane) dihydrochloride (radical initiator; trade name: WAKO V-50) were added to the solution and dissolved for 10 minutes at 65° C. Then a homogeneous mixture of ethylenically unsaturated monomers consisting of 216 g 2-ethylhexyl acrylate, 216 g butyl acrylate, 36 g styrene and 372 g methyl methacrylate was continuously added over a period of 4 hours at 65° C. The reaction mixture was held for one additional hours at 65° C., followed by the addition of 1.2 g 2,2′-Azobis(2-amidinopropane) dihydrochloride (radical initiator; trade name: WAKO V-50) and 6 g methyl methacrylate for post-initiation. The reaction mixture was held for two additional hours at 70° C. before allowed to cool to ambient temperature, which yielded the final product ZYW.sub.SV as a yellowish aqueous dispersion. This dispersion proved to be perfectly storage stable for >3 months at 40° C.

PREPARATION OF FINAL DISPERSIONS ZYW.SUB.S.XV (EXAMPLE 5)

(9) Example 4 was repeated but the reaction product of Example 2 was used instead of the reaction product of Example 1 to yield as a final product, ZYW.sub.SXV as a yellowish aqueous dispersion. This dispersion proved to be perfectly storage stable for >3 months at 40° C.

PREPARATION OF FINAL DISPERSIONS ZYWXV (COMPARATIVE EXAMPLE 6)

(10) Example 4 was repeated but the reaction product of Comp. Example 3 was used instead of the reaction product of Example 1 to yield as a final product, ZYWXV as a yellowish aqueous dispersion.

(11) Characteristics of final dispersions of examples 4 and 5 and comparative example 6 are summarized in Table 2 and are obtained according to the test methods described in the specification.

(12) TABLE-US-00002 TABLE 2 Composition (g) of Examples 4, 5 and Comparative Example 6: Component Example 4 Example 5 Comp. Example 6 Emulsifier Polymer 1505 g Example 1 (377.8 g solids) Emulsifier Polymer 1505 g Example 2 (377.8 g solids) Emulsifier Polymer 1505 g Comp. Example 3 (377.8 g solids) Deionized water 660 g 660 g 660 g WAKO V-50 7.2 g 7.2 g 7.2 g 2-Ethylhexyl acrylate 216 g 216 g 216 g Butyl acrylate 216 g 216 g 216 g Styrene 36 g 36 g 36 g Methyl methacrylate 372 g 372 g 372 g WAKO V-50 1.2 g 1.2 g 1.2 g Methyl methacrylate 6.0 g 6.0 g 6.0 g Solids content % 40.0% 40.2% 39.5% Dynamic viscosity 159 mPas 246 mPas 10320 mPas (mPas; 23° C.; 25 1/s) Amine value 55 53 51 (mg KOH/g solids) Acid value (mg 33 30 30 KOH/g solids) Particle size average 61 nm 61 nm 63 nm (nm) Overall residual 0.06% 0.08% 0.65% monomer content (%) pH 5.4 5.3 5.3

(13) From table 2, it can be concluded that at 40% solids content the dispersions 4 and 5 of the present invention show a dynamic viscosity level in the range 100-300 mPas (measured at a shear rate of 25 s.sup.−1 @ 23° C.), which proves to be excellent for further handling and formulation. Residual monomer levels (combined amount of residual monomers) are found to be below 0.1% for Examples 4 and 5. Those facts represent a clear advantage over Comparative Example 6 which is analog to the prior art published in U.S. Pat. No. 6,653,370 B2. Comparative Example 6 uses unsaturated fatty acids for the reparation of the emulsifier polymer, as it was done in U.S. Pat. No. 6,653,370 B2. Comparing the residual monomer levels of Example 4 and 5 (<0.1%) to the residual monomer levels of Comparative Example 6 (>0.6%) which contains unsaturated fatty acid moieties shows a strong effect which can be attributed to the presence of unsaturated fatty acids in Example 6.

(14) Without being bound by theory, it is hypothesized that the presence of unsaturated fatty acids during radical initiated emulsion polymerization reactions leads to the formation of stabilized fatty acid radicals by radical transfer from growing polymer chains to the unsaturated fatty acid moieties. This radical transfer terminates the growing polymer chains, which leads to incomplete conversion of ethylenically unsaturated monomers, which leads to higher residual monomer levels in the final products (this might cause some VOC and regulatory issues for the final product in certain applications).

(15) Furthermore, Comparative Example 6 shows a very high dynamic viscosity of >10000 mPas (shear rate of 25 s-1 @ 23° C.) at an overall solids content of <40%. It has surprisingly been found that replacing the unsaturated tall oil fatty acid (used in Comparative Example 6 and in U.S. Pat. No. 6,653,370 B2) by a saturated fatty acid (coconut oil fatty acid; Example 5) leads to a huge decrease in dynamic viscosity while long term storage stability (>3 months @ 40° C.) is not negatively affected. This finding represents a clear advantage over the prior art as higher solid contents for the dispersions according to the invention are possible while still keeping the dynamic viscosity in a reasonable and workable range for formulation and further processing. Example 5, which uses saturated fatty acids, displays a dynamic viscosity of <300 (shear rate of 25 s-1 @ 23° C.) at an overall solids content of >40%.

(16) Although Example 4 of prior art U.S. Pat. No. 6,653,370 B2 only exhibits 120 mPas (shear rate 100 s-1 @ 23° C.) at a solid content of 39.7% despite the fact that unsaturated fatty acids (tall oil fatty acids) are used, it was observed that in this case, the low viscosity can only be achieved by addition of >3.5% butyl glycol as solvent. The use of saturated fatty acids as outlined in the present invention eliminates the need of additional organic solvents to bring down the dynamic viscosity. This represents a clear advantage over the prior art with respect to VOC regulations and eco-friendliness.

EXAMPLE 7: PREPARATION AND EVALUATION OF THE PROPERTIES OF A STAIN-BLOCKING PRIMER PREPARED FROM AQUEOUS DISPERSION ACCORDING TO THE PRESENT INVENTION

(17) 7.1. Formulation of a Primer

(18) For evaluating the tannin- and marker blocking performance of the hybrid resins according to the invention the following primer formulations have been prepared as follow: 1. In a first step a mill base has been prepared according to the following formulation:

(19) TABLE-US-00003 TABLE 3 Composition of Mill Base 1: Amount [g] Substance 18.93 g De-ionized water  8.71 g ADDITOL ® VXW 6208 (dispersing additive) 15.44 g ASP 600 (extender) 40.08 g KRONOS ® 2059 (pigment) 14.20 g Blanc Fixe micro (extender)  2.64 g ADDITOL ® VXW 6386 (defoamer)   100 g

(20) The components of Mill Base 1 were mixed and grinded in a pearl mill containing glass beads of 1.5 mm for 30 minutes at approx. 3000 rpm. 2. In a second step the mill base was blended with the respective binder resins to yield the final stain-blocking primers:

(21) TABLE-US-00004 TABLE 4 Composition of Stain Blocking Primers 1 to 3: Stain Blocking Stain Blocking Stain Blocking Component Primer 1 Primer 2 Primer 3 Mill Base 1 50 g 50 g 50 g Example 4 — 43.57 g — (17.43 g solids) Example 5 — — 43.36 g (17.43 g solids) DUROXYN ® EF 38.73 g — — 2107w/45WA (17.43 g solids) Deionized water Amount adjusted to yield 55% overall solids content

(22) The components of Stain Blocking Primers 1 to 3 were blended and mixed upon stirring at ambient temperature to yield the respective stain blocking primers.

(23) Stain Blocking Primer 1 is based on the commercial cationic 1K-epoxy stain-blocking resin DUROXYN® EF 2107w/45WA. It serves as a 1K-epoxy based reference primer with known excellent tannin- and stain-blocking ability.

(24) 7.2. Top-Coat Formulation

(25) For evaluating the tannin- and marker blocking performance of the hybrid resins according to the invention the following top-coat formulation has been used. This top-coat formulation has been evaluated to show insignificant tannin- and marker-blocking if used without stain-blocking primer (see also evaluations below). Therefore, it is used as reference top-coat with low blocking ability.

(26) 1. In a first step a mill base has been prepared according to the following formulation:

(27) TABLE-US-00005 TABLE 5 Composition of Mill Base 2: Amount [g] Substance 17.10 g  De-ionized water 3.60 g ADDITOL ® VXW 6208 (dispersing additive) 1.70 g Propylene glycol 0.80 g ADDITOL ® VXW 6214 (slip and underground wetting agent) 1.90 g ADDITOL ® VXW 4973 (defoamer) 69.30 g  Kronos 2310 (pigment) 5.30 g Acrysol RM 2020 (rheology modifier) 0.30 g Surfynol DF-66 (defoamer)  100 g

(28) The components of Mill Base 2 were mixed and grinded in a pearl mill containing glass beads of 1.5 mm for 30 minutes at approx. 3000 rpm.

(29) 2. In a second step the mill base was blended with other components to yield the final top-coat formulations:

(30) TABLE-US-00006 TABLE 6 Composition of Top-Coat 1: Amount [g] Substance 57.30 g  RESYDROL ® VAY 6278w/45WA (binder resin) 30.00 g  Mill Base 2 5.70 g Ultralube E-359 (wax-emulsion) 0.40 g ADDITOL ® VXL 4930 (slip and leveling agent) 6.60 g De-ionized water  100 g

(31) The mill base was carefully mixed into the binder resin. Then the other components were added and mixed upon stirring at ambient temperature to yield the respective Top-Coat 1.

(32) 7.3. Evaluation of Tannin-Blocking Ability

(33) For evaluating the tannin-blocking performance of the Stain Blocking Primers 1 to 3 a Merbau-wood board has been divided in 4 equal sections. On sections 1 to 3 the Stain Blocking Primers 1 to 3 have been applied in 100 μm wet film thickness using a standardized coating bar. On section 4 (control section) Top-Coat 1 has been applied in 100 μm wet film thickness using a standardized coating bar, serving as control area with less tannin blocking ability.

(34) After drying of the first coat for 8 hours at ambient temperature, all sections have been top-coated with Top-Coat 1 in 100 μm wet film thickness using a standardized coating bar. After drying of the topcoat for 24 hours at ambient temperature the Merbau-wood board has been aged for 7 days at 40° C. and 90% relative humidity.

(35) Finally, the tannin-blocking efficiency has been rated from 0-5 by observation with the human eye. Higher values indicate better tannin-blocking efficiency (0 . . . no tannin-blocking at all—very strong tannin-related discoloration of the top-coat layer; 5 . . . excellent tannin-blocking—no tannin-related discoloration of the top-coat layer).

(36) The results of this observation have been summarized in the following table:

(37) TABLE-US-00007 TABLE 7 Tannin-Blocking Efficiency on Merbau-wood: Section 1 Section 2 Section 3 Section 4 1.sup.st coating Stain Stain Stain Blocking Top-Coat 1 layer Blocking Blocking Primer 3 (primer) Primer 1 Primer 2 2.sup.nd coating Top-Coat 1 Top-Coat 1 Top-Coat 1 Top-Coat 1 layer (top-coat) Tannin- 5 5 5 1 blocking efficiency

(38) The tannin-blocking performance of the binder resins according to the invention (present in Stain Blocking Primer 2 and 3) was found to be comparable to the tannin blocking performance of the commercial stain-blocking resin DUROXYN® EF 2107w/45WA (present in Stain Blocking Primer 1). In case no stain-blocking primer was used and two layers of Top-Coat 1 were applied instead, no significant tannin-blocking was observed.

(39) 7.4 Evaluation of Marker-Blocking Ability

(40) For evaluating the marker-blocking performance of the Stain Blocking Primers 1 to 3 a Leneta card has been coated with a commercial interior wall-paint (Behr Interior Flat-Ultra Pure White® 1050) in 100 μm wet film thickness using a standardized coating bar. After drying of the paint for 7 days at ambient temperature, continuous horizontal lines have been drawn on the painted area using different commercial text-markers of various colors: RED Marks-A-lot Permanent BLACK Marks-A-Lot Permanent BLUE Gel pen Pilot G-2 BLACK Gel pen Pilot G-2 RED Gel pen Pilot G-2 GREEN Window Mega Marker BLUE Window Mega Marker PENCIL Bic No. 2

(41) After application of the markers, the Laneta card has been stored at ambient temperature for at least 7 days prior to further usage. For testing of the marker-blocking efficiency, the Laneta card has been divided in 4 equal vertical sections, each of them showing the continuous horizontal marker lines. On sections 1 to 3 the Stain Blocking Primers 1 to 3 have been applied in 100 μm wet film thickness using a standardized coating bar. On section 4 (control section) Top-Coat 1 has been applied in 100 μm wet film thickness using a standardized coating bar, serving as control area with less marker-blocking ability. After drying of the first coat for 8 hours at ambient temperature, all sections have been top-coated with Top-Coat 1 in 100 μm wet film thickness using a standardized coating bar. After drying of the topcoat for 24 hours at ambient temperature the marker-blocking efficiency in its overall appearance has been rated from 0-5 by observation with the human eye. Higher values indicate better marker-blocking efficiency (0 . . . no marker-blocking at all—very strong marker-related discoloration of the top-coat layer; 5 . . . excellent marker-blocking—no marker-related discoloration of the top-coat layer).

(42) The results of this observation have been summarized in the following table:

(43) TABLE-US-00008 TABLE 8 Marker-Blocking Efficiency on marked Laneta Card: Section 1 Section 2 Section 3 Section 4 1.sup.st coating layer Stain Stain Stain Top-Coat 1 (primer) Blocking Blocking Blocking Primer 1 Primer 2 Primer 3 2.sup.nd coating layer Top-Coat 1 Top-Coat 1 Top-Coat 1 Top-Coat 1 (top-coat) Marker-blocking 4 4 5 1 efficiency (overall appearance rating)

(44) The marker-blocking performance of the binder resins according to the invention (present in Stain Blocking Primer 2 and 3) was found to be comparable to the marker blocking performance of the commercial stain-blocking resin DUROXYN® EF 2107w/45WA (present in Stain Blocking Primer 1). In case no stain blocking primer was used and two layers of Top-Coat 1 were applied instead, no significant marker blocking was observed.

(45) 7.5 Evaluation of Cold Check Resistance

(46) For evaluating the cold check performance of the Stain Blocking Primers 1 to 3 a standard US pine-wood board has been coated on one side with the respective Stain Blocking Primers 1 to 3 using a brush. After 8 hours of drying at ambient temperature half of the coated area has been top-coated with Top-Coat 1.

(47) After drying of the pine wood board for 7 days at ambient temperature and humidity, the test specimen has been subjected to the following cyclic test for 10 repeated cycles:

(48) Cold Check Testing Cycle: 1. QUV-A exposure of the coated side of the board for 24 hours according to DIN EN ISO 4892-3/cycle 1 2. Water immersion of the coated side of the board for 6 hours at 23° C. in tab-water 3. Immediate freezing of the water soaked board at −18° C. for 16 hours 4. 2 hours of thawing at 23° C. and ambient relative humidity 5. Repeat steps 1 to 4 for 10 times

(49) This cyclic test is meant to mimic the freeze-thaw-resistance of a coating in outdoor weathering conditions, including UV exposure and water soaking. The results of this cyclic test are summarized in the following table.

(50) TABLE-US-00009 TABLE 9 Cold check testing results: Pine Board 1 Pine Board 2 Pine Board 3 1.sup.st coating layer Stain Blocking Primer 1 Stain Blocking Primer 2 Stain Blocking Primer 3 (one side of the board; full board area) 2.sup.nd coating layer Top-Coat 1 Top-Coat 1 Top-Coat 1 (on top of 1.sup.st coating layer; half board area) Observations Severe cracking of No cracking, blistering. No cracking. blistering. during cyclic cold primer layer after 3.sup.rd flaking or peeling of flaking or peeling of check testing cycle; the primer layer or the the primer layer or the Flaking and peeling of top-coated area top-coated area primer layer and cracking observed after observed after of top-coated area after completion of 10 completion of 10 5.sup.th cycle; cycles cycles Testing discontinued after 5.sup.th cycle

(51) The cold check testing performance of the binder resins according to the invention (present in Stain Blocking Primer 2 and 3) was found to be superior to the cold check testing performance of the commercial 1K-epoxy stain-blocking resin DUROXYN® EF 2107w/45WA (present in Stain Blocking Primer 1). Those testing results indicate that the binder resins according to the present invention are superior to state-of-the art 1K-epoxy based systems in terms of cold check resistance and may show enhanced external durability, especially in cold and wet climates.

(52) 7.6 Evaluation of Adhesion Promotion

(53) Surprisingly, it has been found that the Epoxy/amino/fatty acid/acrylic hybrid resins according to the present invention show a significant adhesion-promotion effect when added to waterborne 2K-epoxy systems. This adhesion promotion effect especially becomes very obvious on hard-to-adhere substrates for 2K-epoxy systems, e.g. CED pre-coated steel plates.

(54) Typical levels of addition for the binder resins according to the present invention are found in the range of 1%-20% of the combined amount of epoxy resin and epoxy hardener, based on the solid content of all components.

(55) For evaluating the adhesion promotion performance of the binder resins according to the present invention, the following 2K-epoxy monocoat formulations have been prepared. 2K-Epoxy Formulation 2 contains Example 5 as adhesion promotion additive (8.4% of combined amount of epoxy resin and epoxy hardener based on solid content of all components).

(56) TABLE-US-00010 TABLE 10 Composition of 2K-Epoxy Formulations 1 and 2: 2K-Epoxy 2K-Epoxy Part Component Formulation 1 Formulation 2 1 De-ionized water 15.81 g  15.81 g  ADDITIOL ® VXW 6208/60 (wetting- and dispersing 3.53 g 3.53 g agent) ADDITOL ® VXW 6393 (defoamer) 0.30 g 0.30 g 2 Silitin Z86 (extender) 6.83 g 6.83 g Printex U (carbon black pigment) 0.46 g 0.46 g Bayferrox 306 (iron oxide black pigment) 23.07 g  23.07 g  Heucorin FR (flash rust inhibitor) 1.45 g 1.45 g EWO 21.34 g  21.34 g  3 ADDITOL ® VXW 6393 (defoamer) 0.20 g 0.20 g Texanol (coalescing agent) 0.66 g 0.66 g 4 ADDITOL ® VXW 6388 (thickener) 0.50 g 0.50 g ADDITOL ® VXW 6503N (substrate wetting agent) 0.33 g 0.33 g 5 BECKOCURE ® EH 2260w/41WA (epoxy hardener) 30.60 g  30.60 g  Example 5 (adhesion promoter) — 7.17 g 6 BECKOPDX ® EP 2384w/57WA (epoxy resin) 38.28 g  38.28 g  143.36 g  150.53 g 

(57) Parts 1 and 2 of the formulation have been pre-mixed on a dissolver, followed by grinding in a pearl mill containing glass beads of 1.5 mm for 30 minutes at approximately 3000 rpm. Then, parts 3 and 4 were added to this mixture and mixed-in upon stirring. Finally, the components of part 5 were added in the given order and mixed-in upon stirring at ambient temperature. The epoxy resin (part 6) was added to the formulation at the very end—immediately before application—and blended by stirring at ambient temperature.

(58) The 2K-Epoxy Formulations 1 and 2 have been applied on a steel plate (GARDOBOND 265/6800/00) which has been pre-coated and cured with a standard automotive CED-resin in a dry film thickness of 25-30 μm. The adhesion properties of the 2K-Epoxy Formulations 1 and 2 to the standard automotive CED-resin have been evaluated after 1 week of drying at 23° C. and 50% relative humidity according to DIN EN ISO 2409:2013.

(59) Adhesion testing of 2K-Epoxy Formulation 1 according to DIN EN ISO 2409 resulted in a total loss of adhesion (adhesion rating: 5) of the 2K-Epoxy monocoat.

(60) Adhesion testing of 2K-Epoxy Formulation 2 (containing Example 5 as adhesion promoter) according to DIN EN ISO 2409 resulted in very good adhesion properties to the pre-coated, cured standard automotive CED-resin (adhesion rating: 1).

(61) Surprisingly, it has been found that the Epoxy/amino/fatty acid/acrylic hybrid resins according to the present invention show a significant adhesion-promotion effect when added to waterborne 2K-epoxy systems. Adhesion promoting effects for other resin technologies and substrates are also likely to be observed.