PRODUCTION OF SURFACE TREATED AL OR AL ALLOY PLATE EXCELLENT IN COATING FILM ADHESIVITY AND CORROSION RESISTANCE AFTER COATING

摘要

PURPOSE: To develop a surface treated Al or Al alloy plate excellent in coating film adhesivity in the case of coating thereon and in corrosion resistance after coating by anodic electrolyzing the Al plate or the Al alloy plate in an aq. solution containing a specific acid. ;CONSTITUTION: A porous alumite coating film is formed on the surface of the Al plate or the Al alloy plate by applying current by using the metal plate such as Al plate or Al alloy plate as an anode in the acidic aq. solution containing one or more kinds from phosphoric acid, sulfuric acid, oxalic acid and chromic acid to anodic electrolytic treat the surface. The surface treated Al plate or Al alloy plate excellent in coating film adhesivity, in corrosion resistance after coating and suitable as a panel material for automobiles or domestic electric products is produced by applying an epoxy resin coating material or the like thereto.;COPYRIGHT: (C)1994,JPO