| 摘要 |
A fast curing, high solids coating composition that is adapted for use as an automotive topcoat and which upon curing forms a hard, glossy, durable coating exhibiting excellent resistance to solvents and water. The coating composition contains greater than about 60 percent by weight of nonvolatile solids and, exclusive of pigments, solvents and other nonreactive components, consists essentially of: (A) a bifunctional copolymer bearing hydroxy functionality and pendant epoxy functionality, having a number average molecular weight (Mn) of between about 1500 and about 10,000 and a glass transition temperature (Tg) of between about -25 DEG and about 70 DEG : (B) a reactive catalyst comprising at least one hydroxy functional organophosphate ester selected from certain mono-and diesters of phosphoric acid; (C) an amine-aldehyde crosslinking agent; and (D) optionally, a hydroxy functional additive. The hydroxy functional organophosphate ester is included in the composition in an amount sufficient to provide between about 0.67 and about 1.4 equivalents of acid functionality in copolymer (A), and the amino crosslinking agent is included in the composition in an amount sufficient to provide at least about 0.4 equivalents of nitrogen crosslinking functionality for each equivalent of hydroxy functionality included in the composition.
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