Composition for coating materials

Patent metadata

Field	Value
Publication number	US-2023312974-A1
Application number	US-202118024813-A
Country	US
Kind code	A1
Filing date	Sep 2, 2021
Priority date	Sep 9, 2020
Publication date	Oct 5, 2023
Grant date	—

Abstract

The present invention provides a water-repellent coating composition which enables easy removal of dirt while having good appearance due to high compatibility of a water-repellent component with other materials. The present invention provides a coating composition, comprising a siloxane group-containing polymer (A) and a crosslinking agent (B), wherein the siloxane group-containing polymer (A) is a block copolymer comprising an A block and a B block, and containing, in the A block, at least a structural unit derived from a siloxane group-containing vinyl monomer (a) and containing, in the B block, a structural unit derived from a hydroxyl group-containing vinyl monomer (b) and, as necessary, a structural unit derived from another vinyl monomer (c) copolymerizable with the vinyl monomers (a) and (b), and is a copolymer having a molecular weight distribution (Mw/Mn) of 2.0 or less and polymerized by living radical polymerization.

First claim

1 . A coating composition, comprising a siloxane group-containing polymer (A) and a crosslinking agent (B),
wherein the siloxane group-containing polymer (A) is a block copolymer comprising an A block and a B block, and containing, in the A block, at least a structural unit derived from a siloxane group-containing vinyl monomer (a) and containing, in the B block, a structural unit derived from a hydroxyl group-containing vinyl monomer (b) and, as necessary, a structural unit derived from another vinyl monomer (c) copolymerizable with the vinyl monomers (a) and (b), and the siloxane group-containing polymer (A) is a copolymer having a molecular weight distribution (Mw/Mn) of 2.0 or less and polymerized by living radical polymerization.

2 . The coating composition according to claim 1 , wherein the siloxane group-containing polymer (A) is an AB-type diblock copolymer or an ABA-type triblock copolymer.

3 . The coating composition according to claim 1 , wherein the siloxane group-containing polymer (A) has a weight average molecular weight (Mw) of 5,000 to 100,000.

4 . The coating composition according to claim 1 , wherein the living radical polymerization is a method in which the polymerization is performed using an organic tellurium compound represented by formula (I):

wherein R 1 represents a C 1 to C 8 alkyl group, aryl group, substituted aryl group, or aromatic heterocyclic group, R 2 and R 3 each represent a hydrogen atom or a C 1 to C 8 alkyl group, R 4 represents an aryl group, a substituted aryl group, an aromatic heterocyclic group, an acyl group, an oxycarbonyl group, or a cyano group.

5 . The coating composition according to claim 1 , further comprising a hydroxyl group-containing polymer (C).

6 . The coating composition according to claim 1 , wherein the blending ratio of the siloxane group-containing polymer (A) and the hydroxyl group-containing polymer (C) is 15:85 to 80:20 in terms of a weight ratio of the siloxane group-containing polymer (A):the hydroxyl group-containing polymer (C).

7 . The coating composition according to claim 1 , wherein the siloxane group-containing vinyl monomer (a) has a number average molecular weight (Mn) of 500 to 50,000.

8 . The coating composition according to claim 1 , wherein the crosslinking agent (B) is an isocyanate-based crosslinking agent.

9 . The coating composition according to claim 2 , wherein the siloxane group-containing polymer (A) has a weight average molecular weight (Mw) of 5,000 to 100,000.

10 . The coating composition according to claim 2 , wherein the living radical polymerization is a method in which the polymerization is performed using an organic tellurium compound represented by formula (I):

wherein R 1 represents a C 1 to C 8 alkyl group, aryl group, substituted aryl group, or aromatic heterocyclic group, R 2 and R 3 each represent a hydrogen atom or a C 1 to C 8 alkyl group, R 4 represents an aryl group, a substituted aryl group, an aromatic heterocyclic group, an acyl group, an oxycarbonyl group, or a cyano group.

11 . The coating composition according to claim 2 , further comprising a hydroxyl group-containing polymer (C).

12 . The coating composition according to claim 2 , wherein the blending ratio of the siloxane group-containing polymer (A) and the hydroxyl group-containing polymer (C) is 15:85 to 80:20 in terms of a weight ratio of the siloxane group-containing polymer (A):the hydroxyl group-containing polymer (C).

13 . The coating composition according to claim 2 , wherein the siloxane group-containing vinyl monomer (a) has a number average molecular weight (Mn) of 500 to 50,000.

14 . The coating composition according to claim 2 , wherein the crosslinking agent (B) is an isocyanate-based crosslinking agent.

Assignees

• Nippon Paint Automotive Coatings Co Ltd
• Otsuka Chemical Co Ltd

Inventors

• Akizuki Shinsuke
• Miwa Yasunori
• Morimoto Sachiko
• Inoue Yuki
• Masumoto Satoru

Classifications

• C09D153/00 Primary

  Coating compositions based on block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Coating compositions based on derivatives of such polymers · CPC title

• C09D7/63

  organic · CPC title

• C09D175/04 Primary

  Polyurethanes · CPC title

• C08G18/792

  formed by oligomerisation of aliphatic and/or cycloaliphatic isocyanates or isothiocyanates · CPC title

• C08G18/6469

  having silicon · CPC title