Patent ID: 8734949
Filing Date: 2014-05-27
Classification: C09D,Y10T

Abstract:
1. A method for passivating a metallic surface, which comprises treating the surface in alternating layers with a) then with b), a) always being the first and last layer, such that a multicoat passivating layer is provided on said metallic surface, said multicoat passivating layer comprising 3n+2 alternating layers where n is an integer and the layer sequence is a), b), n times {a), b)} and lastly a), where a) and b) are: a) an acidic, aqueous preparation comprising at least one water-soluble copolymer (A) synthesized from b) an aqueous preparation comprising at least one water-soluble and/or water-dispersible species (B) which comprises cationic and/or procationic groups.