Inventors:
Joseph W. Holubka - Livonia MI
Ray A. Dickie - Birmingham MI
Assignee:
Ford Motor Company - Dearborn MI
International Classification:
C08L 7604
C08G 1880
Abstract:
Resin composition suitable for high-solids solvent-based coating composition comprises chain-extendable, crosslinkable polyol of molecular weight from about 200 to 1000, having at least three hydroxyl groups, chain-extendable diblocked diisocyanate diurethane oligomer of molecular weight between about 300 to 1500, crosslinking agent reactive with the hydroxy functionality of the polyol and substantially unreactive with de-blocked isocyanate functionality of the biblocked diisocyanate diurethane oligomer, and, preferably, catalyst(s). The composition cures at elevated temperature to provide a coating on a substrate, such as steel, which coating is highly resistant to corrosion, humidity and solvents and provides corrosion protection for the substrate. The diblocked diisocyanate diurethane oligomer is preferably the reaction product of a diol with a half-blocked diisocyanate, wherein the half-blocked diisocyanate is preferably the reaction product of an organic diisocyanate with monofunctional blocking agent. The polyol is preferably the reaction product of a diol of molecular weight about 60 to 500 with a diepoxide of molecular weight about 100 to 1000 such as bisphenol A epichlorohydrin epoxy resin, hydantoin epoxy resin and the like.