| 摘要 |
PROBLEM TO BE SOLVED: To provide a galvanized steel sheet having as excellent corrosion resistance (white rust resistance) and adhesiveness as a chromate treated sheet, without using chromium. SOLUTION: The galvanized steel sheet with excellent corrosion resistance has a coating layer of 0.01-1 g/m<2> , which is formed by means of coating a mixed aqueous solution of primary phosphate of polyvalent metal, silica sol, and a phosphonic acid compound, on a galvanized steel sheet, and then drying it, as the first layer, and an organic coating layer of 0.3-2 g/m<2> as the second layer. The first coating layer is preferably formed by means of coating an aqueous solution including silica sol of 10-100 pts.wt., and the phosphonic acid compound of 1-100 pts.wt. against the primary phosphate of a polyvalent metal of 100 pts.wt., and drying it. The first coating layer preferably includes one or more of Mg, Al, Ca, Zn, and Mn, as the polyvalent metal.
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