abstract |
An organic composite coated steel sheet having excellent chromate dissolution resistance, wet adhesion, and corrosion resistance before and after working. The steel sheet comprises a chromate-silica film on at least one face of a zinc or zinc base alloy plated steel sheet, the silica-added chromate film having about 5 to 500 mg/m 2 in terms of metal Cr content and being formed from a chromate solution containing about 25 to 70 wt% of Cr +6 based upon total Cr content. A resin coating film is adhered to the chromate-silica film and is formed from an aqueous paint. The aqueous paint includes an aqueous anionic resin and/or an aqueous nonionic resin, a reducing agent, and a water-dispersed silica. The resin coating film is deposited in a dry weight amount of about 0.1 to 3 g/m 2 . |