Claims
- 1. A water-based coating composition comprising an aqueous medium and a particulate vinyl polymer, wherein at least 95 wt. % of particles of said polymer have a minor axis A and a major axis B, said minor and major axes A and B being in a relationship of 1.ltoreq.B/A.ltoreq.1.5 and individually ranging from 30 .mu.m to 400 .mu.m, and said polymer has an acid value of from 30 to 150 mgKOH/g.
- 2. A water-base coating composition comprising:
- (I) an aqueous vinyl polymer solution formed of an aqueous medium and a particulate vinyl polymer according to claim 1, said particulate vinyl polymer having been neutralized with a base so that said particulate vinyl polymer is dissolved in said aqueous medium, and
- (II) an aqueous dispersion of a polymer having a weight average molecular weight of from 200,000 to 2,000,000;
- wherein the ratio of said aqueous vinyl polymer (I) to said aqueous dispersion (II) ranges from 5/95 to 95/5 in terms of polymer solid.
- 3. A water-base coating composition according to claim 2, wherein said polymer in said aqueous dispersion (II) has a second-order transition temperature of from 30.degree. to 120.degree. C.
- 4. A water-base coating composition comprising:
- (III) a vinyl polymer solution formed of water and a particulate vinyl polymer according to claims 1, said particulate vinyl polymer having been neutralized with a base so that said particulate vinyl polymer is dissolved in said water; and
- (IV) an aqueous dispersion formed of water and a urethane polymer which is obtained by extending a urethane prepolymer with water or amine after or while neutralizing the urethane prepolymer with a tertiary amine, and said urethane prepolymer comprising (e) an aliphatic or alicyclic diisocyanate, (f) a diol compound having a number average molecular weight of from 500 to 5,000 and (g) an acidic-group-containing diol and having an NCO/OH equivalent ratio of from 1.1 to 1.9.
- 5. A water-base coating composition according to claim 4, wherein the mixing ratio of said vinyl polymer solution (III) to said aqueous dispersion (IV) is from 5/95 to 95/5 in terms of solid.
- 6. A water-base coating composition according to claim 4, wherein said particulate vinyl polymer has a second-order transition temperature of from 20.degree. to 110.degree. C. and a weight average molecular weight of from 6,000 to 30,000.
- 7. A water-base coating composition according to claim 1, wherein said polymer comprises:
- (a) 30 to 90 wt. % of methyl methacrylate,
- (b) 0 to 30 wt. % of an aromatic vinyl compound,
- (c) 4 to 30 wt. % of an acidic-group-containing vinyl compound and
- (d) 0 to 66 wt. % of a further vinyl monomer copolymerizable with said methyl methacrylate, said aromatic vinyl compound and said acidic-group-containing vinyl compound.
- 8. A water-base coating composition according to claim 7, wherein said acid-group-containing vinyl compound (c) comprises methacrylic acid.
- 9. A water-base coating composition according to claim 1, wherein said polymer has a second-order transition temperature of from 10.degree. to 150.degree. C. and a weight average molecular weight of from 6,000 to 100,000.
- 10. A water-base coating composition according to claim 1, wherein said polymer has been polymerized by suspension polymerization.
- 11. A water-base coating composition comprising an aqueous medium and a particulate vinyl polymer according to claim 1, wherein 50 to 100% of said particular vinyl polymer have been neutralized with a base having a boiling point not higher than 200.degree. C. so that said particulate vinyl polymer is dissolved in said aqueous medium.
Priority Claims (1)
Number |
Date |
Country |
Kind |
5-250538 |
Oct 1993 |
JPX |
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Parent Case Info
This is a Division, of application Ser. No. 08/319,036 filed on Oct. 6, 1994 now U.S. Pat. No 5,496,904.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
4320207 |
Watanabe et al. |
Mar 1992 |
|
5496904 |
Moriya et al. |
Mar 1996 |
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Divisions (1)
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Number |
Date |
Country |
Parent |
319036 |
Oct 1994 |
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