| abstract |
A method and composition for treating metal surfaces improves the paint adhesion of the metal surface, particularly its resistance to delamination of paint over a stressed area in the finished metal upon exposure to hot water. The composition is an aqueous composition of an organo-functional silane, a compound of a group IV-B element, and a polymer blend having a plurality of carboxylic functional groups and a plurality of hydroxyl groups. The method includes contacting a metal surface, such as aluminum, with the composition. The polymer blend is preferably a mixture of polymethylvinylether-co-maleic acid and polyvinyl alcohol. The organo-functional silane is preferably an epoxy silane. |