Method for treating surface of zinc-aluminum-magnesium alloy-plated steel sheet

摘要

Provided is a method for obtaining a chemical conversion coating-treated zinc-aluminum-magnesium alloy-plated steel sheet having an excellent corrosion resistance and adhesion performance with respect to a resin coating. A method for treating the surface of a zinc-aluminum-magnesium alloy-plated steel sheet using a metal surface treatment agent, wherein the metal surface treatment agent contains predetermined amounts of a compound (A) having a zirconyl ([Zr=O]