Curable powder film-forming composition having chemical resistance

摘要

A curable powder film-forming composition which includes:(a) about 55 to 80 percent by weight based on the total weight of resin solids in the film forming composition, of an epoxy functional copolymer having a Tg of about 77° F. to about 158° F. formed by free radical initiated polymerization of:(i) about 25 to about 75 percent by of a glycidyl functional ethylenically unsaturated monomer, and(ii) about 25 to about 75 percent by weight of a copolymerizable ethylenically unsaturated monomer or mixture of monomers free of glycidyl functionality;(b) about 15 to about 35 percent by weight of a polycarboxylic acid; and(c) about 1.0 to about 4.0 percent by weight of a polyisocyanate at least partially capped with a capping agent. A multi-component composite coating composition is also provided, which includes a pigmented film-forming base coat and a transparent top coat of the film-forming composition described above.