Patent ID: 8399061
Filing Date: 2013-03-19
Classification: C08F,C09D

Abstract:
1. A two-stage process for the corrosion-control treatment of a metallic substrate, which comprises (I) in a first stage immersing the substrate in a bath of an aqueous corrosion preventative K, which results in conversion at the substrate surface, and (II) in a second stage immersing the substrate treated as per stage (I) in a bath of an aqueous coating material comprising, as a coating material, a water-dispersible and/or water-soluble polymer P with a gradient in the concentration of covalently bonded hydrophilic groups along the polymer main chain, the polymer P comprising covalently bonded ligands A, the ligands A being distributed randomly in the polymer P and being capable of forming chelates with metal ions released during the corrosion of the substrate and/or with a surface of the substrate, and crosslinking functional groups B, the crosslinking functional groups B being capable of forming covalent bonds to one or more crosslinkers V.