Water-based metal surface treatment agent, metal surface treatment method and surface-treated metal material

摘要

PROBLEM TO BE SOLVED: To provide a chromium-free water-based surface treatment agent for a metal, which can impart the metal corrosion resistance, blackening resistance and thermal-yellowing resistance which are equivalent to or more excellent than those of a chromate film, and chemical resistance, adhesiveness to a coating film, fingerprint resistance and formability as well, and is stable for a long period of time in a wide pH range even when kept in high concentration.;SOLUTION: The chromium-free water-based surface treatment agent for a metal includes at least one of vanadium compounds (a) shown by the general formula (I) (wherein M represents a cation; P represents an anion containing phosphor; F presents an anion containing fluorine; x is 0 to 10, y is 0 to 10, z is 0 to 10, w is 0 to 10, and z+w=0.2 or more; and the valency of V is four or three).;COPYRIGHT: (C)2012,JPO&INPIT