SURFACE-COATED ALUMINUM-CONTAINING GALVANIZED STEEL SHEET AND METHOD FOR PRODUCING SAME

摘要

This surface-coated aluminum-containing galvanized steel sheet is obtained by forming a composite coating film that contains a water-dispersible resin (A) and a cobalt compound (B) by applying an aqueous surface treatment agent, which contains the water-dispersible resin (A), the cobalt compound (B) and water and has a pH within the range of 7.5-10, to a plated steel sheet and drying the agent thereon. The constituent ratio by mass of the water-dispersible resin (A) in the composite coating film is 90% or more. The dry mass of the composite coating film per one surface of the plated steel sheet is within the range of 0.5-3.5 g/m2.