| abstract |
The film-forming composition contains an aromatic compound having an amino group and an aromatic ring in one molecule, and a thio compound (except for sulfuric oxo acid having a pKa of -1.9 or less and salts thereof). As for pH of the composition for film formation, 4-10 are preferable. It is preferable that a thio compound is ionized in solution and becomes an anion, and thiosulfate and thiocyanate are especially preferable. By making the composition for film formation contact the surface of a metal member, a film is formed in the surface of a metal member and a surface treatment metal member is obtained. |