Multilayer coatings for metal substrates

摘要

A multilayered coating (10) that is applied to a metal substrate (12). The coating comprises a protective zone of an insoluble crystalline phosphate formed by reaction of the substrate (12) with zinc phosphate. A film (16) of a polymer resin is deposited on the insoluble crystalline phosphate zone (14). In one embodiment, the multilayered coating (10) includes a coat of paint (18) that is applied to the polymer resin (16). A process for applying the multilayered coating to the metal substrate includes the steps of: applying a zinc phosphating solution to at least a portion of the substrate, which converts the surface to a zone of an insoluble crystalline phosphate; rinsing the zone; and autodepositing a film of a polymer resin thereupon.