Patent ID: 8536259

Claim:
A curable, formaldehyde free coating composition comprising: (i) a composition comprising (a) a polyacid copolymer comprising at least two carboxylic acid groups, anhydride groups, or salts thereof, (b) a hydroxyl group-containing compound bearing at least two hydroxyl groups as an independent compound or incorporated into the polyacid copolymer backbone, and (c) a phosphorus-containing catalyst; and (ii) calcium aluminosilicate powder having a total alkali content of less than about 2 wt. % based on the total weight of the calcium aluminosilicate powder, a median particle size of about 250 microns or less, and a surface area from about 1 m 2 /g to about 3 m 2 /g, wherein the ratio of the number of equivalents of said carboxylic acid groups, anhydride groups, or salts thereof to the number of equivalents of said hydroxyl groups is from about 1/0.01 to about 1/3.