FORMATION OF COLORED FILM ON ALUMINUM SURFACE BY SPONTANEOUS COLOR DEVELOPMENT

摘要

PURPOSE:To form a colored film on the desired part of an Al material by spontaneous color development by jetting powder of a metal other than Al on the surface of the Al material so that the powder bites into the surface and by carrying out anodic oxidation. CONSTITUTION:Powder of a metal other than Al, e.g., Fe, Cr, Mn or Si is jetted on the surface of an Al material with compressed air at a high speed so that the powder bites into the surface in a prescribed distribution. The surface of the Al material is then degreased and anodically oxidized. A masking plate can be used during the jetting. By this method, a colored film is formed on the part exposed to the jetting by spontaneous color development and an anodic oxide film is formed on the other part.