Aqueous dispersion type thermosetting coating composition

Abstract

Disclosed in an aqueous dispersion type thermosetting coating composition which comprises fine thermosetting resin particles composed of (A) a polyester resin having a specific hydroxyl value and (B) a copolymer resin, which are dispersed in the presence of (C) a surface active agent and/or a thickener in (D) a necessary amount of water.

What is claimed is: 
     
       1. An aqueous dispersion type thermosetting coating composition comprising (A) fine .[.thermosetting.]. water-insoluble .Iadd.thermosetting .Iaddend.resin particles consisting essentially of (a) a preformed polyester-modified vinyl resin having a hydroxyl value of 30 to 200, which is formed by solution graft-polymerizing (i) an unsaturated polyester resin formed by .[.reaction between an.]. .Iadd.reacting 1-10% by weight of at least one α,β-.Iaddend.unsaturated dicarboxylic acid.Iadd., at least one carboxylic acid component selected from the group consisting of phthalic acid, phthalic anhydride, isophthalic acid, isophthalic anhydride, trimellitic acid, trimellitic anhydride, pyromellitic acid, pyromellitic anhydride, tetrahydrophthalic acid, tetrahydrophthalic anhydride, hexahydrophthalic acid, hexahydrophthalic anhydride, methylhexahydrophthalic acid, methylhexahydrophthalic anhydride, 3,6-endomethylene-tetrahydrophthalic anhydride, succinic acid, succinic anhydride, adipic acid, sebacic acid, benzoic acid and p-tert-butyl-benzoic acid .Iaddend.and .[.a.]. .Iadd.at least one .Iaddend.polyhydric alcohol, with (ii) at least one α,β-monoethylenically unsaturated monomer, and optionally with (iii) a phosphoric acid group-containing α,β-monoethylenically unsaturated monomer, and (b) a performed cross-linkable copolymer resin derived from a monomer mixture comprising (iv) an N-alkoxymethylated monomer of an α,β-monoethylenically unsaturated carboxylic acid amide and (ii) at least one α,β-monoethylenically unsaturated monomer, (B) a surface active agent and/or a thickener, and (C) a necessary amount of water. 
     
     
       2. An aqueous dispersion type thermosetting coating composition as set forth in claim 1, wherein said (A) fine water-insoluble thermosetting resin particles consist essentially of 5 to 90% by weight of said polyester-modified vinyl resin having a hydroxyl value of 30 to 200, which is formed by solution graft-polymerizing (i) 5 to 50% by weight of said unsaturated polyester resin with (ii) 95 to 50% by weight of at least one said α,β-monoethylenically unsaturated monomer and 95 to 10% by weight of said cross-linkable copolymer resin, and said (B) surface active agent and/or thickener is present in an amount of .[.0.1.]. .Iadd.0.01 .Iaddend.to 1.0% by weight based on said resin particles. .[.3. An aqueous dispersion type thermosetting coating composition as set forth in claim 2 wherein said unsaturated polyester resin comprises 1 to 10% by weight of at least one α,β-unsaturated dicarboxylic acid as one 
     
     
        constituent..]. 4. An aqueous dispersion type thermosetting coating composition as set forth in claim 2 wherein the α,β-monoethylenically unsaturated monomer graft-polymerized with said unsaturated polyester resin is a monomer mixture comprising (ii)' 5 to 50% by weight of a hydroxyalkyl ester of an α,β-monoethylenically unsaturated carboxylic acid and (ii)" 95 to 50% by weight of a copolymerizable α,β-monoethylenically 
     
     
        unsaturated monomer other than said monomer (ii)'. 5. An aqueous dispersion type thermosetting coating composition as set forth in claim 2 wherein said cross-linkable copolymer resin is derived from a monomer mixture comprising (iv) 5 to 30% by weight of an N-alkoxymethylated monomer of an α,β-monoethylenically unsaturated carboxylic acid amide, (ii)'" 0.5 to 10% by weight an α,β-monoethylenically unsaturated carboxylic acid and (ii)"" 60 to 90% by weight of a copolymerizable α,β-monoethylenically unsaturated monomer other 
     
     
        than said monomers (iv) and (ii)'". 6. An aqueous dispersion type thermosetting coating composition as set forth in claim 1 wherein said (A) fine water-insoluble thermosetting resin particles consist essentially of (a) 5 to 90% by weight of said polyestermodified vinyl resin having a hydroxy value of 30 to 200, which is formed by solution graft-polymerizing (i) 2 to 50% by weight of said unsaturated polyester resin with (ii) 95 to 40% by weight of at least one said α,β-monoethylenically unsaturated monomer and (iii) 0.01 to 10% by weight of said phosphoric acid group-containing α,β-monoethylenically unsaturated monomer and (b) 95 to 10% by weight of said cross-linkable copolymer resin, and said (B) surface active agent and/or thickener is present in an amount of 0.01 to 1.0% by weight based on said resin particles. .[.7. An aqueous dispersion type thermosetting coating composition as set forth in claim 6 wherein said unsaturated polyester resin comprises 1 to 10% by weight of at least one α,β-unsaturated dicarboxylic acid as one 
     
     
        constituent..]. 8. An aqueous dispersion type thermosetting coating composition as set forth in claim 6 wherein the α,β-monoethylenically unsaturated monomer graft-polymerized with said unsaturated polyester resin is a monomer mixture comprising (ii)' 1 to 40% by weight of a hydroxyalkyl ester of an α,β-monoethylenically unsaturated carboxylic acid and (ii)" 99 to 60% by weight of a copolymerizable α,β-monoethylenically 
     
     
        unsaturated monomer other than said monomer (ii)'. 9. An aqueous dispersion type thermosetting coating composition as set forth in claim 6 wherein said cross-linkable copolymer resin is derived from a monomer mixture comprising (iv) 5 to 30% by weight of an N-alkoxymethylated monomer of an α,β-monoethylenically unsaturated carboxylic acid, (ii)'" 0.5 to 10% by weight of an α,β-monoethylenically unsaturated carboxylic acid and (ii)"" 60 to 90% by weight of a copolymerizable α,β-monoethylenically unsaturated monomer other 
     
     
        than said monomers (iv) and (ii)'". 10. An aqueous dispersion type thermosetting coating composition which comprises (A) fine water-insoluble thermosetting resin particles consisting essentially of (a) 15 to 95% by weight of a preformed polyester-modified vinyl resin having a hydroxyl value of 10 to 150, which is formed by solution graft-polymerizing (i) 2 to 40% by weight of an unsaturated polyester resin formed by .[.reaction between an.]. .Iadd.reacting 1-10% by weight of at least one α,β-.Iaddend.unsaturated dicarboxylic acid.Iadd., at least one carboxylic acid component selected from the group consisting of phthalic acid, phthalic anhydride, isophthalic acid, isophthalic anhydride, trimellitic acid, trimellitic anhydride, pyromellitic acid, pyromellitic anhydride, tetrahydrophthalic acid, tetrahydrophthalic anhydride, hexahydrophthalic acid, hexahydrophthalic anhydride, methylhexahydrophthalic acid, methylhexahydrophthalic anhydride, 3,6-endomethylene-tetrahydrophthalic anhydride, succinic acid, succinic anhydride, adipic acid, sebacic acid, benzoic acid and p-tert-butyl-benzoic acid .Iaddend.and .[.a.]. .Iadd.at least one .Iaddend.polyhydric alcohol with 98 to 60% by weight of a monomer mixture comprising (iv) an N-alkoxymethylated monomer of an α,β-monoethylenically unsaturated carboxylic acid amide and (ii) at least one α,β-monoethylenically unsaturated monomer and (b) 85 to 5% by weight of a preformed phosphoric acid group-containing copolymer resin derived from a monomer mixture comprising (iii) a phosphoric acid group-containing α,β-monoethylenically unsaturated monomer and (ii) at least one α,β-monoethylenically unsaturated monomer, (B) a surface active agent and/or a thickener in an amount of 0.01 to 1.0% by weight based on said resin particles and (C) a necessary amount of water. .[.11. An aqueous dispersion type thermosetting coating composition as set forth in claim 10 wherein said unsaturated polyester resin comprises 1 to 10% by weight of at least one 
     
     
        α,β-unsaturated dicarboxylic acid as one constituent..]. 12. An aqueous dispersion type thermosetting coating composition as set forth in claim 10 where the α,β-monoethylenically unsaturated monomer mixture graft-polymerized with said unsaturated polyester resin comprises (ii)' 1 to 30% by weight of a hydroxyalkyl ester of an α,β-monoethylenically unsaturated carboxylic acid, (iv) 5 to 30% by weight of an N-alkoxymethylated monomer of an α,β-monoethylenically unsaturated carboxylic acid amide and (ii)" 60 to 90% by weight of a copolymerizable α,β-monoethylenically unsaturated monomer other than said 
     
     
        monomers (iv) and (ii)'. 13. An aqueous dispersion type thermosetting coating composition as set forth in claim 10 wherein said phosphoric acid group-containing copolymer resin is derived from a monomer mixture comprising (iii) 0.01 to 10% by weight of a phosphoric acid group-containing α,β-monoethylenically unsaturated monomer, (ii)'" 0.5 to 10% by weight of an α,β-monoethylenically unsaturated carboxylic acid, (ii)' 1 to 30% by weight of a hydroxyalkyl ester of an α,β-monoethylenically unsaturated carboxylic acid and (ii)" 70 to 90% by weight of a copolymerizable α,β-monoethylenically unsaturated monomer other than said 
     
     
        monomers (iii), (ii)'" and (ii)'. .Iadd.14.  An aqueous dispersion type thermosetting coating composition as set forth in claim 1 wherein 30-70% by weight of the polyhydric alcohol is reacted. .Iaddend. .Iadd.15. An aqueous dispersion type thermosetting coating composition as set forth in claim 14 wherein 29-69% by weight of said carboxylic acid component is reacted. .Iaddend. .Iadd.16. An aqueous dispersion type thermosetting coating composition as set forth in claim 14, wherein said (A) fine water-insoluble thermosetting resin particles consist essentially of 5 to 90% by weight of said polyester-modified vinyl resin having a hydroxyl value of 30 to 200, which is formed by solution graft-polymerizing (i) 5 to 50% by weight of said unsaturated polyester resin with (ii) 95 to 50% by weight of at least one said α,β-monoethylenically unsaturated monomer and 95 to 10% by weight of said cross-linkable copolymer resin, and said (B) surface active agent and/or thickener is present in an amount of 0.01 to 1.0% by weight based on said resin particles. .Iaddend. .Iadd.17. An aqueous dispersion type thermosetting coating composition as set forth in claim 14 wherein the α,β-monoethylenically unsaturated monomer graft-polymerized with said unsaturated polyester resin is a monomer mixture comprising (ii)' 5 to 50% by weight of a hydroxyalkyl ester of an α,β-monoethylenically unsaturated carboxylic acid and (ii)" 95 to 50% by weight of a copolymerizable α,β-monoethylenically 
     
     
        unsaturated monomer other than said monomer (ii)'. .Iaddend. .Iadd.18.  An aqueous dispersion type thermosetting coating composition as set forth in claim 14 wherein said cross-linkable copolymer resin is derived from a monomer mixture comprising (iv) 5 to 30% by weight of an N-alkoxymethylated monomer of an α,β-monoethylenically unsaturated carboxylic acid amide, (ii)"' 0.5 to 10% by weight of an α,β-monoethylenically unsaturated carboxylic acid and (ii)"" 60 to 90% by weight of a copolymerizable α,β-monoethylenically unsaturated monomer other than said monomers (iv) and (ii)"'. .Iaddend. .Iadd.19. An aqueous dispersion type thermosetting coating composition as set forth in claim 14 wherein said (A) fine water-insoluble thermosetting resin particles consist essentially of (a) 5 to 90% by weight of said polyester-modified vinyl resin having a hydroxy value of 30 to 200, which is formed by solution graft-polymerizing (i) 2 to 50% by weight of said unsaturated polyester resin with (ii) 95 to 40% by weight of at least one said α,β-monoethylenically unsaturated monomer and (iii) 0.01 to 10% by weight of said phosphoric acid group-containing α,β-monoethylenically unsaturated monomer and (b) 95 to 10% by weight of said cross-linkable copolymer resin, and said (B) surface active agent and/or thickener is present in an amount of 0.01 to 1.0% by weight 
     
     
        based on said resin particles. .Iaddend. .Iadd.20.  An aqueous dispersion type thermosetting coating composition as set forth in claim 15 wherein said (A) fine water-insoluble thermosetting resin particles consist essentially of 5 to 90% by weight of said polyester-modified vinyl resin having a hydroxyl value of 30 to 200, which is formed by solution graft-polymerizing (i) 5 to 50% by weight of said unsaturated polyester resin with (ii) 95 to 50% by weight of at least one said α,β-monoethylenically unsaturated monomer and 95 to 10% by weight of said cross-linkable copolymer resin, and said (B) surface active agent and/or thickener is present in an amount of 0.01 to 1.0% by weight based on said resin particles. .Iaddend. .Iadd.21. An aqueous dispersion type thermosetting coating composition as set forth in claim 15 wherein the α,β-monoethylenically unsaturated monomer graft-polymerized with said unsaturated polyester resin is a monomer mixture comprising (ii)' 5 to 50% by weight of a hydroxyalkyl ester of an α,β-monoethylenically unsaturated carboxylic acid and (ii)" 95 to 50% by weight of a copolymerizable α,β-monoethylenically unsaturated monomer other than said monomer (ii)'. .Iaddend. .Iadd.22. An aqueous dispersion type thermosetting coating composition as set forth in claim 15 wherein said cross-linkable copolymer resin is derived from a monomer mixture comprising (iv) 5 to 30% by weight of an N-alkoxymethylated monomer of an α,β-monoethylenically unsaturated carboxylic acid amide, (ii)"' 0.5 to 10% by weight of an α,β-monoethylenically unsaturated carboxylic acid and (ii)"" 60 to 90% by weight of a copolymerizable α,β-monoethylenically unsaturated monomer other than said monomers (iv) and (ii)"'. .Iaddend. .Iadd.23. An aqueous dispersion type thermosetting coating composition as set forth in claim 15 wherein said (A) fine water-insoluble thermosetting resin particles consist essentially of (a) 5 to 90% by weight of said polyester-modified vinyl resin having a hydroxy value of 30 to 200, which is formed by solution graft-polymerizing (i) 2 to 50% by weight of said unsaturated polyester resin with (ii) 95 to 40% by weight of at least one said α,β-monoethylenically unsaturated monomer and (iii) 0.01 to 10% by weight of said phosphoric acid group-containing α,β-monoethylenically unsaturated monomer and (b) 95 to 10% by weight of said cross-linkable copolymer resin, and said (B) surface active agent and/or thickener is present in an amount of 0.01 to 1.0% by weight based on said resin particles. .Iaddend. .Iadd.24. An aqueous dispersion type thermosetting coating composition as set forth in claim 19, wherein the α,β-monoethylenically unsaturated monomer graft-polymerized with said unsaturated polyester resin is a monomer mixture comprising (ii)' 1 to 40% by weight of a hydroxyalkyl ester of an α,β-monoethylenically unsaturated carboxylic acid and (ii)" 99 to 60% by weight of a copolymerizable α,β-monoethylenically 
     
     
        unsaturated monomer other than said monomer (ii)'. .Iaddend. .Iadd.25.  An aqueous dispersion type thermosetting coating composition as set forth in claim 19 wherein said cross-linkable copolymer resin is derived from a monomer mixture comprising (iv) 5 to 30% by weight of an N-alkoxymethylated monomer of an α,β-monoethylenically unsaturated carboxylic acid, (ii)"' 0.5 to 10% by weight of an α,β-monoethylenically unsaturated carboxylic acid and (ii)"" 60 to 90% by weight of a copolymerizable α,β-monoethylenically unsaturated monomer other than said monomers (iv) and (ii)'". .Iaddend. .Iadd.26. An aqueous dispersion type thermosetting coating composition as set forth in claim 23 wherein the α,β-monoethylenically unsaturated monomer graft-polymerized with said unsaturated polyester resin is a monomer mixture comprising (ii)' 1 to 40% by weight of a hydroxyalkyl ester of an α,β-monoethylenically unsaturated carboxylic acid and (ii)' 99 to 66% by weight of a copolymerizable α,β-monoethylenically unsaturated monomer other than said monomer (ii)'. .Iaddend. .Iadd.27. An aqueous dispersion type thermosetting coating composition as set forth in claim 23 wherein said cross-linkable copolymer resin is derived from a monomer mixture comprising (iv) 5 to 30% by weight of an N-alkoxymethylated monomer of an α,β-monoethylenically unsaturated carboxylic acid, (ii)"' 0.5 to 10% by weight of an α,β-monoethylenically unsaturated carboxylic acid and (ii)"" 60 to 90% by weight of a copolymerizable α,β-monoethylenically unsaturated monomer other than said 
     
     
        monomers (iv) and (ii)'". .Iaddend. .Iadd.28.  An aqueous dispersion type thermosetting coating composition as set forth in claim 10 wherein 30-70% by weight of the polyhydric alcohol is reacted. .Iaddend. .Iadd.29. An aqueous dispersion type thermosetting coating composition as set forth in claim 28 wherein 29-69% by weight of said carboxylic acid component is reacted. .Iaddend. .Iadd.30. An aqueous dispersion type thermosetting coating composition as set forth in claim 28 wherein the α,β-monoethylenically unsaturated monomer mixture graft-polymerized with said unsaturated polyester resin comprises (ii)' 1 to 30% by weight of a hydroxyalkyl ester of an α,β-monoethylenically unsaturated carboxylic acid, (iv) 5 to 30% by weight of an N-alkoxymethylated monomer of an α,β-monoethylenically unsaturated carboxylic acid amide and (ii)" 60 to 90% by weight of a copolymerizable α,β-monoethylenically unsaturated monomer other than said monomers (iv) and (ii)". .Iaddend. .Iadd.31. An aqueous dispersion type thermosetting coating composition as set forth in claim 29 wherein the α,β-monoethylenically unsaturated monomer mixture graft-polymerized with said unsaturated polyester resin comprises (ii)' 1 to 30% by weight of a hydroxyalkyl ester of an α,β-monoethylenically unsaturated carboxylic acid, (iv) 5 to 30% by weight of an N-alkoxymethylated monomer of an α,β-monoethylenically unsaturated carboxylic acid amide and (ii)" 60 to 90% by weight of a copolymerizable α,β-monoethylenically unsaturated monomer other than said 
     
     
        monomers (iv) and (ii)". .Iaddend. .Iadd.32.  An aqueous dispersion type thermosetting coating as set forth in claim 28 wherein said phosphoric acid group-containing copolymer resin is derived from a monomer mixture comprising (iii) 0.01 to 10% by weight of a phosphoric acid group-containing α,β-monoethylenically unsaturated monomer, (ii)"' 0.5 to 10% by weight of an α,β-monoethylenically unsaturated carboxylic acid, (ii)' 1 to 30% by weight of a hydroxyalkyl ester of an α,β-monoethylenically unsaturated carboxylic acid and (ii)" 70 to 90% by weight of a copolymerizable α,β-monoethylenically unsaturated monomer other than said monomers (iii), (ii)'" and (ii)'. .Iaddend. .Iadd.33. An aqueous dispersion type thermosetting coating composition as set forth in claim 29 wherein said phosphoric acid group-containing copolymer resin is derived from a monomer mixture comprising (iii) 0.01 to 10% by weight of a phosphoric acid group-containing α,β-monoethylenically unsaturated monomer, (ii)"' 0.5 to 10% by weight of an α,β-monoethylenically unsaturated carboxylic acid, (ii)' 1 to 30% by weight of a hydroxyalkyl ester of an α,β-monoethylenically unsaturated carboxylic acid and (ii)" 70 to 90% by weight of a copolymerizable α,β-monoethylenically unsaturated monomer other than said monomers (iii), (ii)'" and (ii)'. .Iaddend.