Copolymerized polyester, water dispersion and aqueous paint using the same

Patent metadata

Field	Value
Publication number	US-11312880-B2
Application number	US-201916957186-A
Country	US
Kind code	B2
Filing date	Apr 10, 2019
Priority date	May 7, 2018
Publication date	Apr 26, 2022
Grant date	Apr 26, 2022

Abstract

The present invention aims to provide a copolymerized polyester which is effective as a binder ingredient for aqueous paint, and a copolymerized polyester aqueous dispersion.

First claim

The invention claimed is:

1. An aqueous paint, comprising:
a water dispersion (B) and at least one member selected from the group consisting of an amino resin as a crosslinking agent (C), a pigment (D) and an additive (E),
wherein the water dispersion (B) comprises a copolymerized polyester (A), an organic solvent and water, and
wherein the copolymerized polyester (A) contains a polyvalent carboxylic acid ingredient and a polyhydric alcohol ingredient as copolymerization ingredients, wherein, when a total content of the polyvalent carboxylic acid ingredient is taken as 100% by mol, a sum of a content of an aromatic polyvalent carboxylic acid ingredient and a content of an alicyclic polyvalent carboxylic acid ingredient is 100% by mol and, when a total content of the polyhydric alcohol ingredient is taken as 100% by mol, a content of a glycol ingredient (a) is 10 to 40% by mol, wherein the glycol ingredient (a) has such a structure that two hydroxyl groups are bonded by an alkylene group having a number of carbon atoms of 5 or less, wherein the alkylene group has, as a side chain thereof, an alkyl group having a number of carbon atoms of 2 or more, and wherein the copolymerized polyester has a glass transition temperature of −10 to 20° C. and an acid value of 150 to 400 equivalents/ton.

2. The aqueous paint according to claim 1 , wherein the glycol ingredient (a) has a structure represented by the following formula (1)

wherein R 1 and R 2 are each independently a straight or branched alkyl group having a number of carbon atoms of 1 to 10, and n is an integer of 1 to 3; and each of the plural R 1 and R 2 may be the same or different; and wherein the number of carbon atoms of any one of R 1 and R 2 is 2 or more.

3. The aqueous paint according to claim 2 , wherein the formula (1) is 2,2-butylethylpropanediol.

4. The aqueous paint according to claim 1 , wherein the copolymerized polyester (A) has a number-average molecular weight within a range of 5000 to 13000.

5. A coated metal plate, comprising a metal plate coated with the aqueous paint according to claim 1 .

Assignees

• Toyo Boseki

Inventors

• Iwashita Yuji
• Mikami Tadahiko

Classifications

• C08G63/127

  Acids containing aromatic rings · CPC title

• C08G63/183

  Terephthalic acids · CPC title

• C08G63/199

  Acids or hydroxy compounds containing cycloaliphatic rings · CPC title

• C09D167/02 Primary

  Polyesters derived from dicarboxylic acids and dihydroxy compounds (C09D167/06 takes precedence) · CPC title

• C09D7/20

  Diluents or solvents · CPC title