Epoxy resin emulsions for electrocoating

Patent metadata

Field	Value
Publication number	US-2020377740-A1
Application number	US-201916427869-A
Country	US
Kind code	A1
Filing date	May 31, 2019
Priority date	May 31, 2019
Publication date	Dec 3, 2020
Grant date	—

Abstract

In this structure, each of R1-R4 is independently a hydrogen atom, a C1-C8 alkyl group, a C3-C8 cycloalkyl group, an aryl group, an aralkyl group, a halide group, a cyano group, a nitro group, a blocked isocyanate group, or a C1-C8 alkyloxy group or wherein any two or more of R1-R4 may be a fused ring.

First claim

What is claimed is:

1 . An epoxy resin emulsion comprising:
A. a continuous phase comprising an aqueous carrier and an acid; and B. a dispersed phase comprising an epoxy resin that is the reaction product of an amine compound and a first epoxy reactant, wherein said first epoxy reactant comprises the reaction product of:
(1) an aromatic diol monomer having the structure;

wherein each of R 1 -R 4 is independently a hydrogen atom, a C 1 -C 8 alkyl group, a C 3 -C 8 cycloalkyl group, an aryl group, an aralkyl group, a halide group, a cyano group, a nitro group, a blocked isocyanate group, or a C 1 -C 8 alkyloxy group or wherein any two or more of R 1 -R 4 may be a fused ring;
(2) a di-glycidyl ether of Bisphenol A and/or a di-glycidyl ether of catechol; and
(3) a C8-C18 alkyl phenolic end-capping agent, wherein said emulsion is free of sulfamic acid.

2 . The epoxy resin emulsion of claim 1 wherein said epoxy resin has a weight average molecular weight (Mw) of from about 1,000 to about 100,000 g/mol.

3 . The epoxy resin emulsion of claim 1 wherein said epoxy resin has a weight average molecular weight (Mw) of from about 5,000 to about 20,000 g/mol.

4 . The epoxy resin emulsion of claim 1 wherein said epoxy resin has a weight average molecular weight (Mw) of from about 5,000 to about 10,000 g/mol.

5 . The epoxy resin emulsion of claim 1 wherein said aromatic diol monomer is 1,2-dihydroxybenzene.

6 . The epoxy resin emulsion of claim 1 wherein said two hydroxyl groups of said aromatic diol monomer are located at the 1 and 2 positions of said benzyl ring respectively.

7 . The epoxy resin emulsion of claim 1 wherein said two hydroxyl groups of said aromatic diol monomer are located at the 1 and 3 positions of said benzyl ring respectively.

8 . The epoxy resin emulsion of claim 1 wherein said two hydroxyl groups of said aromatic diol monomer are located at the 1 and 4 positions of said benzyl ring respectively.

9 . The epoxy resin emulsion of claim 1 wherein said reaction product is further defined as a reaction product of said (1) aromatic diol monomer, said (2) di-glycidyl-ether of Bisphenol A, and Bisphenol A and (3) said alkyl phenolic end-capping agent.

10 . The epoxy resin emulsion of claim 1 wherein said reaction product is further defined as being free of reaction with Bisphenol A.

11 . The epoxy resin emulsion of claim 1 wherein said reaction product is further defined as a reaction product of said (1) aromatic diol monomer, said (2) di-glycidyl-ether of Bisphenol A, and (3) a C 12 alkyl phenolic end-capping agent. 12 The epoxy resin emulsion of claim 1 wherein said reaction product is further defined as a reaction product of said (1) aromatic diol monomer, said (2) di-glycidyl-ether of catechol, and (3) a C 12 alkyl phenolic end-capping agent.

13 . The epoxy resin emulsion of claim 1 wherein said amine compound comprises a primary and/or secondary hydroxylamine.

14 . The epoxy resin emulsion of claim 1 consisting essentially of said aqueous carrier, said acid, and said epoxy resin.

15 . The epoxy resin emulsion of claim 1 wherein said epoxy resin cures to form a coating that has a surface roughness Ra of less than 0.4 um as measured using ISO 4287 (R) on pretreated electrogalvanized substrates.

16 . The epoxy resin emulsion of claim 1 wherein said epoxy resin cures to form a coating that has an edge protection of less than 3 as measured using VDA 233-102 at 6 cycles on perforated electrogalvanized substrates.

17 . The epoxy resin emulsion of claim 1 wherein said aqueous carrier is water, said acid is formic acid, said aromatic diol monomer is 1,2-dihydroxybenzene, said epoxy resin has a weight average molecular weight of from about 5,000 to about 10,000 g/mol, and said epoxy resin cures to form a coating that has a surface roughness Ra of less than 0.4 μm as measured using ISO 4287 (R) on pretreated electrogalvanized substrates and that has an edge protection of less than 3 as measured using VDA 233-102 at 6 cycles on perforated electrogalvanized substrates.

18 . The epoxy resin emulsion of claim 17 consisting essentially of said water, said formic acid, and said epoxy resin.

19 . The epoxy resin emulsion of claim 18 wherein said reaction product is further defined as a reaction product of said (1) aromatic diol monomer, said (2) di-glycidyl-ether of Bisphenol A, and (3) a C 12 alkyl phenolic end-capping agent.

20 . An epoxy resin emulsion that is free of sulfamic acid and consists essentially of:
A. a continuous phase comprising water and formic acid; and B. a dispersed phase comprising an epoxy resin that has a weight average molecular weight of from about 5,000 to about 10,000 g/mol and is the reaction product of aminopropyldiethanolamine, diethanolamine, and a first epoxy reactant, wherein said first epoxy reactant comprises the reaction product of catechol, a di-glycidyl ether of Bisphenol A, and 4-docecylphenol as an end-capping agent, wherein said epoxy resin cures to form a coating that has a surface roughness Ra of less than 0.4 μm as measured using ISO 4287 (R) on pretreated electrogalvanized substrates and that has an edge protection of less than 3 as measured using VDA 233-102 at 6 cycles on perforated electrogalvanized substrates.

Assignees

• Axalta Coating Systems Ip Co

Inventors

• Jin Xin
• Ren Chun

Classifications

• C09D5/4457

  containing special additives, e.g. pigments, polymeric particles · CPC title

• C08G59/1438

  containing oxygen · CPC title

• C09D5/4442

  Binder characterised by functional groups · CPC title

• C09D5/08

  Anti-corrosive paints · CPC title

• C08G59/14

  Polycondensates modified by chemical after-treatment · CPC title