Patent ID: 7780838

Claim:
A method of treating the surface of a metallic workpiece comprising the steps of: a) providing a surface comprising at least one of a metal, a metal alloy, or a mixture thereof; whereby at least one of the metal or metal alloy is anodizable and is used as an electrode; b) contacting said metallic surface with an anodizing solution; c) providing at least one other electrode in contact with said anodizing solution; and d) passing a direct current or an alternating current between said metallic surface and said other electrode through said anodizing solution to form a gel layer on said metallic surface; e) wherein said anodizing solution is an aqueous solution having a pH greater than 7 and comprises: i. a phosphorus and oxygen containing anion in a concentration of from 0.01 to 100 g/L calculated as PO 4 ; ii. at least one water-soluble inorganic hydroxide; iii. at least one surfactant; iv. at least one alkaline hydrolyzed silane or a mixture of at least one alkaline hydrolyzed silane and at least one alcohol having at least one alkaline radical group; and v. at least one alkali metal, to form a layer containing non-conductive polymer on said metallic surface, wherein the non-conductive polymer is transformed to a gel layer and wherein the gel layer is stabilized with the aid of at least one surfactant, at least one alcohol, or a derivative or mixture thereof, wherein a current density of between 2 and 12 A/dm 2 is provided.