| abstract |
PROBLEM TO BE SOLVED: To provide corrosion resistance, blackening resistance and heat yellowing resistance equal to or higher than those of chromate, and can provide chemical resistance, paint adhesion, fingerprint resistance and workability and a wide range of pH. Providing a chromium-free aqueous metal surface treatment that is stable for a long time even at high concentrations. SOLUTION: General formula (I): [Chemical 1] (Wherein M is a cation; P is an anion containing phosphorus; F is an anion containing fluorine; x is 0-10; y is 0-10; z Is 0-10; w is 0-10; z + w = 0.2 or more; the valence of V is tetravalent or trivalent), and at least one of vanadium compounds (a) An aqueous metal surface treatment agent (A) containing no chromium, obtained by adding [Selection figure] None |