Patent ID: 6488990
Filing Date: 2002-12-03
Classification: B82Y,C23C

Abstract:
A process for treating a metallic surface having at least two separate but sequential steps for applying two different coatings, including contacting said metallic surface with aqueous solution A and then with aqueous solution B, or with aqueous solution B and then with aqueous solution A, at a temperature in the range of from 10 to 100Â° C., whereinsolution A contains an amount of zirconium, hafnium, titanium, silicon and/or boron, and an amount of fluoride in the form of ions and/or complex ions, capable of pickling the metallic surface and generating a coating on the pickled metallic surface, and wherein solution B contains an effective amount of one or more compounds of the type XYZ, X*Y*Z* and/or X*Y*Z*Y*X* where Y is an organic group with 2 to 50 carbon atoms, X and Z are each the same or different and are selected from the group consisting of OHâ€”, SHâ€”, NH2â€”, NHRâ€²â€”, CNâ€”, CH&boxH;CH2â€”, OCNâ€”, CONHOHâ€”, COORâ€², acrylamide-, epoxide-, CH2&boxH;CRâ€³â€”COOâ€”, COOHâ€”, HSO3â€”, HSO4â€”, (OH)2POâ€”, (OH)2PO2â€”, (OH)(ORâ€²)POâ€”, (OH)(ORâ€²)PO2â€”, SiH3â€”, and Si(OH)3â€”, Râ€² is an alkyl group with 1 to 4 carbon atoms, Râ€³ is a hydrogen atom or an alkyl group with 1 to 4 carbon atoms, and X and Z are each bound to Y in their terminal position, Y* is an organic group with 1 to 30 carbon atoms, and X* and Z* are each the same or different and are selected from the group consisting of OHâ€”, SHâ€”, NH2â€”, NHRâ€²â€”, CNâ€”, CH&boxH;CH2â€”, OCNâ€”, CONHOHâ€”, COORâ€², acrylamide-, epoxide-, CH2&boxH;CRâ€³â€”COOâ€”, COOHâ€”, HSO3â€”, HSO4â€”, (OH)2POâ€”, (OH)2PO2â€”, (OH)(ORâ€²)POâ€”, (OH)(ORâ€²)PO2â€”, SiH3â€”, Si(OH)3â€”, Nâ€”CH2â€”PO(OH)2â€”, and â€”Nâ€”[CH2â€”PO(OH)2]2â€”. where Râ€² is an alkyl group with 1 to 4 carbon atoms, where Râ€³ is a hydrogen atom or an alkyl group with 1 to 4 carbon atoms.