Patent ID: 8936836
Filing Date: 2015-01-20
Classification: B05D,B32B,C08G,C08K,C08L,C09D,C23C,Y10T

Abstract:
1. A process comprising coating a metallic surface with an aqueous composition to form a coated metal part, wherein the aqueous composition comprises: a) an organic film former comprising at least one synthetic resin, wherein 70 to 100 wt. % of the content of synthetic resin in the organic film former comprises at least one water-soluble or water-dispersible synthetic resin in a content in the range of from 30 to 150 g/L selected from the group consisting of a polymer, copolymer, block polymer and graft polymer; wherein the water soluble or water-dispersible synthetic resin is based on a synthetic resin selected from the group consisting of polycarbonate, polyurethane, ionomer, poly(meth)acrylate, polyester, polyether and polystyrene, wherein the content of polycarbonate and polyurethane is at least 10 wt. % each and the content of polycarbonate and polyurethane together in the organic film former is at least 50 wt. %; b) at least one 4 to 16 carbon long-chain alcohol as film-forming aid for the organic film former selected from the group consisting of a butanediol, an ethylene glycol ether and a polypropylene glycol ether; c) at least one inorganic crosslinker based on a member selected from the group consisting of titanium, hafnium and zirconium; d) from 2 to 30 g/L of a wax, wherein the wax comprises a cationically stabilized oxidized polyethylene wax with a melting point of about 130° C., and an anionically stabilized paraffin wax with a melting point in the range from 56 to 80° C.; e) A) at least one silane, silanol or siloxane or B) at least one inorganic compound in particle form with an average particle diameter measured on a scanning electron microscope in the range from 0.005 to 0.3 μm; and g) water; wherein the metallic surface is brought into contact with the aqueous composition and a substantially organic film is formed on the metallic surface, which is then dried and optionally also cured; and wherein the dried and optionally also cured film has a film thickness in the range from 0.01 to 10 μm, determined by detaching a defined area of the cured film and weighing it, wherein a ratio of the wax to the organic film former is from 0.02:1 to 2:1.