| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a surface treatment agent containing no phosphor, and to provide a surface treatment method using the surface treatment agent containing no phosphor. <P>SOLUTION: The surface treatment agent is formed of an aqueous solution which contains one or more organic chelating agents selected from aminocarboxylic acids and aminocarboxylates, and in which the concentration of the organic chelating agents is adjusted to 1 g/L to 300 g/L, and the pH is 4.0 to 9.0. The surface treatment method includes the steps of: immersing carbon steel into a treatment liquid in which Fe<SP>2+</SP>is added to the surface treatment agent formed of the aqueous solution that contains one or more organic chelating agents selected from the aminocarboxylic acids and the aminocarboxylates; and adjusting the pH of the treatment liquid, the concentration of the organic chelating agent in the treatment liquid, the concentration of Fe<SP>2+</SP>in the treatment liquid, the concentration of Fe<SP>3+</SP>in the treatment liquid, and the oxidation-reduction potential of the treatment liquid. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
