Method for anti-corrosion pre-treatment of a metal surface containing steel, galvanised steel, aluminium, magnesium and/or a zinc-magnesium alloy

Abstract

Described herein is an improved process for an anticorrosion pretreatment of a metallic surface including steel, galvanized steel, aluminum, magnesium and/or a zinc-magnesium alloy, wherein the metallic surface is brought into contact with an aqueous composition A including a) from 0.01 to 0.5 g/l of a copolymer and the metallic surface is brought into contact with an acidic aqueous composition B including b1) a compound selected from the group consisting of titanium, zirconium and hafnium compounds, wherein the metallic surface is brought into contact i) firstly with the composition A and then with the composition B, ii) firstly with the composition B and then with the composition A and/or iii) simultaneously with the composition A and the composition B. Also described herein is a corresponding aqueous composition A, an aqueous concentrate for producing this composition, a correspondingly coated metallic surface and a method of using a correspondingly coated metallic substrate.

Dependencies are inferred from the claim text.