Asahi Malleable Iron Co., Ltd.

Yasuhiro Hanazima

Masumi Sugioka

Norihiro Ogawa

A colored, anodized aluminum-base article including an aluminum-base substrate, and first and second anodized aluminum oxide films overlaid thereon. The inner, second film has a hardness of about 330 Hv or more, while the outer, first film is more porous than the second film and has a hardness of about 270 Hv or less. The first film is colored with a coloring agent. The article is prepared by anodizing an aluminum-base substrate in an electrolyte bath at a temperature of 20.degree.-40.degree. C. and, subsequently at a temperature not higher than 10.degree. C., the resultant substrate having two types of anodic aluminum oxide films formed thereon being subjected to a coloring treatment.

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Shizuoka, Japan

Yasuhiro Hanazima