Low-temperature curing coating compositions

Patent metadata

Field	Value
Publication number	US-2025043165-A1
Application number	US-202418923993-A
Country	US
Kind code	A1
Filing date	Oct 23, 2024
Priority date	Feb 7, 2017
Publication date	Feb 6, 2025
Grant date	—

Abstract

The present invention is directed towards a coating composition comprising a film-forming polymer comprising active hydrogen-containing functional groups; a blocked polyisocyanate curing agent comprising a blocking group derived from a blocking agent comprising an alpha-hydroxy amide, ester or thioester; and a curing catalyst that does not contain tin, lead, iron, zinc or manganese. Also disclosed are coatings, coated substrates, and methods of coating a substrate.

First claim

We claim:

1 . A coating composition comprising:
an active hydrogen-containing, cationic salt group-containing film forming polymer; a curing catalyst comprising a bicyclic guanidine and/or a bismuth; and a blocked polyisocyanate curing agent comprising:
(i) a first blocking group derived from a first blocking agent comprising an alpha-hydroxy amide, ester, and/or thioester; and
(ii) a second blocking group derived from a second blocking agent comprising an alcohol, a phenolic compound, a tertiary hydroxyl amine, an oxime, and/or an amine;
wherein the composition is substantially free of tin, lead, iron, zinc, or manganese.

2 . The coating composition of claim 1 , comprising:
the curing catalyst in an amount of 0.01 percent by weight to 7 percent by weight based on total weight of resin solids; and/or a blocked polyisocyanate curing agent in an amount of 10 percent by weight to 60 percent by weight based on total weight of resin.

3 . The coating composition of claim 1 , wherein the film forming polymer comprises a residue of a ketimine.

4 . The coating composition of claim 1 , wherein the first blocking agent comprises a compound of the structure:

wherein X is N(R 2 ), O, S; n is 1 to 4; when n=1 and X=N R 2 ), R is hydrogen, a C 1 to C 10 alkyl group, an aryl group, a polyether, a polyester, a polyurethane, a hydroxy-alkyl group, or a thio-alkyl group; when n=1 and X=O or S, R is a C 1 to C 10 alkyl group, an aryl group, a polyether, a polyester, a polyurethane, a hydroxy-alkyl group, or a thio-alkyl group; when n=2 to 4, R is a multi-valent C 1 to C 10 alkyl group, a multi-valent aryl group, a multi-valent polyether, a multi-valent polyester, a multi-valent polyurethane; each R 1 is independently hydrogen, C 1 to C 10 alkyl group, an aryl group, or a cycloaliphatic group; each R 2 is independently hydrogen, a C 1 to C 10 alkyl group, an aryl group, a cycloaliphatic group, a hydroxy-alkyl group, or a thio-alkyl group; and R and R 2 together form a cycloaliphatic, heterocyclic structure.

5 . The composition of claim 1 , wherein the first blocking agent comprises an alpha-hydroxy amide blocking agent.

6 . The coating composition of claim 5 , wherein the alpha-hydroxy amide blocking agent comprises an alkyl glycolamide and/or an alkyl lactamide.

7 . The coating composition of claim 1 , wherein the first blocking agent comprises a compound of the structure:

wherein R 1 is hydrogen or a methyl group; R 2 is a C 1 to C 10 alkyl group; and R 3 is hydrogen or a C 1 to C 10 alkyl group.

8 . The coating composition of claim 1 , wherein the first blocking agent comprises an alkyl glycolamide comprising a C 1 to C 10 mono-alkyl glycolamide, an alkyl lactamide comprising a C 1 to C 10 mono-alkyl lactamide, and/or a racemic lactamide.

9 . A method of coating a substrate comprising applying the coating composition of claim 1 to a portion of a surface of the substrate.

10 . The method of claim 9 , wherein the coating composition is applied to the surface of the substrate by electrodeposition.

11 . A coating formed by at least partially curing the coating composition of claim 1 .

12 . A substrate coated with the coating composition of claim 1 in an at least partially cured state.

13 . A coating composition comprising:
an active hydrogen-containing, cationic salt group-containing film forming polymer; a curing catalyst in an amount of 0.01 percent by weight to 7 percent by weight based on total weight of resin solids and comprising a bicyclic guanidine and/or a bismuth; and a blocked polyisocyanate curing agent in an amount of 10 percent by weight to 60 percent by weight based on total weight of resin solids and comprising a blocking group derived from a blocking agent comprising an alpha-hydroxy amide, ester, and/or thioester; and wherein the composition is substantially free of tin, lead, iron, zinc, or manganese.

14 . The coating composition of claim 13 , wherein the film forming polymer comprises a residue of a ketimine.

15 . The coating composition of claim 13 , wherein the blocking agent comprises a compound of the structure:

wherein X is N(R 2 ), O, S; n is 1 to 4; when n=1 and X=N(R 2 ), R is hydrogen, a C 1 to C 10 alkyl group, an aryl group, a polyether, a polyester, a polyurethane, a hydroxy-alkyl group, or a thio-alkyl group; when n=1 and X=O or S, R is a C 1 to C 10 alkyl group, an aryl group, a polyether, a polyester, a polyurethane, a hydroxy-alkyl group, or a thio-alkyl group; when n=2 to 4, R is a multi-valent C 1 to C 10 alkyl group, a multi-valent aryl group, a multi-valent polyether, a multi-valent polyester, a multi-valent polyurethane; each R 1 is independently hydrogen, C 1 to C 10 alkyl group, an aryl group, or a cycloaliphatic group; each R 2 is independently hydrogen, a C 1 to C 10 alkyl group, an aryl group, a cycloaliphatic group, a hydroxy-alkyl group, or a thio-alkyl group; and R and R 2 together form a cycloaliphatic, heterocyclic structure.

16 . The coating composition of claim 13 , wherein the blocking agent comprises a compound of the structure:

wherein R 1 is hydrogen or a methyl group; R 2 is a C 1 to C 10 alkyl group; and R 3 is hydrogen or a C 1 to C 10 alkyl group.

17 . A method of coating a substrate comprising applying the coating composition of claim 13 to a portion of a surface of the substrate.

18 . The method of claim 17 , wherein the coating composition is applied to the surface of the substrate by electrodeposition.

19 . A coating formed by at least partially curing the coating composition of claim 13 .

20 . A substrate coated with the coating composition of claim 13 in an at least partially cured state.

Assignees

• Ppg Ind Ohio Inc

Inventors

• Eswarakrishnan Venkatachalam
• Zhou Hongying
• Sandala Michael G
• Novak Carolyn A K
• Bice Jo-Ann E
• Dacko Christopher A
• Ro Hyun Wook
• Syput Richard F
• Puodziukynaite Egle
• Wilson Craig A
• Jones Justin M
• Tillman Herbert

Classifications

• C09J163/00

  Adhesives based on epoxy resins; Adhesives based on derivatives of epoxy resins · CPC title

• C09J11/08

  Macromolecular additives · CPC title

• C08L2207/53

  Core-shell polymer · CPC title

• C08G18/80

  Masked polyisocyanates · CPC title

• C08G18/76

  aromatic · CPC title