Anti-corrosive coating compositions and methods for metal materials

摘要

The present invention provides an anti-corrosive coating composition suitable for metal, particularly zinc-coated steel plates, which is free of chromium, is capable of conferring excellent corrosion resistance on the metal coated therewith, and is excellent in storage stability, in which silane coupling agent and/or hydrolyzate condensates thereof is contained in water or an aqueous resin solution or suspension; in addition the composition may additionally contain phosphorus containing ions and/or sulfur-containing compound or sulfur-containing ions; a method for anti-corrosive coating of metal materials and metal materials coated with the composition.