Aqueous coating composition and process of making the same

Patent metadata

Field	Value
Publication number	US-10160875-B2
Application number	US-201415537557-A
Country	US
Kind code	B2
Filing date	Dec 19, 2014
Priority date	Dec 19, 2014
Publication date	Dec 25, 2018
Grant date	Dec 25, 2018

Abstract

A low VOC aqueous coating composition capable of providing coating films with balanced properties of low gloss and good stain resistance.

First claim

What is claimed is:

1. An aqueous coating composition comprising, based on the total solids weight of the aqueous coating composition,
(a) an aqueous acrylic polymer dispersion present in an amount of from 10% to 90% by solids weight;
(b) anionic colloidal silica present in an amount of from 0.1% to 4.3% by solids weight;
(c) a solvent present in an amount of from 0.1% to 7% by weight, wherein the solvent has the following structure:
R 1 —(OR 2 ) n —OH

wherein R 1 is a saturated hydrocarbon group having from 1 to 6 carbon atoms, R 2 is —CH 2 CH 2 — or —CH 2 CH(CH 3 )—; and n is an integer from 1 to 4 when R 2 has the structure of —CH 2 CH 2 —, or n is an integer from 2 to 4 when R 2 has the structure of —CH 2 CH(CH 3 )—;
(d) ammonia present in an amount of from 0.55% to 4.2% by weight;
(e) an amine compound present in an amount less than 1.2% by weight; and
(f) titanium dioxide,
wherein the aqueous coating composition is substantially free of silane coupling agents.

2. The aqueous coating composition of claim 1 , wherein the anionic colloidal silica has a pH value >8.5.

3. The aqueous coating composition of claim 1 , wherein the anionic colloidal silica is present in an amount of from 1% to 3.5% by solids weight.

4. The aqueous coating composition of claim 1 , wherein silica particles in the anionic colloidal silica have a specific surface area of from 20 to 800 m 2 /g.

5. The aqueous coating composition of claim 1 , wherein ammonia is present in an amount of from 1% to 3% by weight.

6. The aqueous coating composition of claim 1 , wherein the solvent is selected from ethylene glycol monobutyl ether, ethylene glycol monohexyl ether, diethylene glycol methyl ether, diethylene glycol monobutyl ether, dipropylene glycol n-butyl ether, dipropylene glycol n-propyl ether, dipropylene glycol methyl ether, or mixtures thereof.

7. The aqueous coating composition of claim 1 , wherein the solvent is present in an amount of from 1% to 6% by weight.

8. The aqueous coating composition of claim 1 , wherein the acrylic polymer has a glass transition temperature of from 0° C. to 60° C.

9. The aqueous coating composition of claim 1 , wherein the aqueous coating composition upon drying exhibits a gloss level of no more than 20 on a vinyl chart or no more than 30 on wood on a 60° Gardner Gloss scale, and both delta b and delta E values smaller than 2.0.

10. A process of preparing the aqueous coating composition of claim 1 , comprising admixing: (a) the aqueous acrylic polymer dispersion, (b) the anionic colloidal silica, (c) the solvent, (d) ammonia, (e) the amine compound, and (f) titanium dioxide.

Assignees

• Dow Global Technologies Llc

Inventors

• Wu Yan
• Xu Yawei
• Yang Xiaohong

Classifications

• C08K5/06

  Ethers; Acetals; Ketals; Ortho-esters · CPC title

• C09D133/12

  Homopolymers or copolymers of methyl methacrylate · CPC title

• C09D5/028

  Pigments; Filters · CPC title

• C09D5/024

  characterised by the additives · CPC title

• C08F265/06

  Polymerisation of acrylate or methacrylate esters on to polymers thereof · CPC title