METHOD FOR ELECTROLYTICALLY COLORING ALUMINUM OR ALUMINUM ALLOY GOLDEN

摘要

PURPOSE:To inhibit the formation of coloring hidering factors and insoluble fine particles by adding a surfactant to an electrolytic coloring bath together with a stannous salt and a decomposable sulfur compound. CONSTITUTION:Al or an Al alloy is anodically oxidized, and it is electrolytically colored in an electrolytic coloring bath contg. a metallic salt after carrying out secondary anodic oxidation by AC electrolysis as required. The coloring bath contains a stannous salt (a), a compound (b) having a sulfur atom in the molecule and releasing it when the compound is slowly decomposed in the soln. or is decomposed by oxidation-reduction reaction under AC conduction, and a surfactant (c) selected among alkanesulfonic acids, salts thereof, alkanolsulfonic acids and salts thereof.