| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a surface treatment agent and a surface treatment method by which a black film can be obtained in the metallic surfaces of zinc, aluminum, magnesium or the alloys thereof without using hexavalent chromium. <P>SOLUTION: The surface treatment agent consists of an acidic aqueous solution of pH ≤6 containing a feed source of sulfite ions and a feed source of oxidizing substance. <P>COPYRIGHT: (C)2003,JPO |
