AQUEOUS CHEMICAL TREATMENT AGENT FOR ALUMINUM OR ALUMINUM ALLOY, CHEMICAL TREATMENT METHOD, AND CHEMICALLY TREATED ALUMINUM AND ALUMINUM ALLOY

摘要

PROBLEM TO BE SOLVED: To provide a chemical treatment technology free of hexavalent chromium having stable and excellent corrosion resistance for treating aluminum, an aluminum alloy, and especially an aluminum die-cast material that have various surface conditions.SOLUTION: There is provided an aqueous chemical treatment agent for surface treatment of aluminum or an aluminum alloy that includes chitosans (A), at least one component (B) selected from the group consisting of a water-soluble trivalent chromium compound, a water-soluble titanium compound and a water-soluble zirconium compound, a nitrate radical (C), and a dissolution type fluorine component (D). Another aqueous chemical treatment agent further including an alkaline-earth metal component (E) is also provided.