| 摘要 |
PROBLEM TO BE SOLVED: To provide a press oil-omissible non-lubricating film removal type plated steel sheet which has excellent adhesion of a coating film and corrosion resistance in a worked zone, contains no chromium, and has reduced environmental loads. SOLUTION: This non-lubricating film removal type plated steel sheet has excellent corrosion resistance in a worked zone and reduced environmental loads. As a lower layer thereof, a Zn-Mg-Al based alloy plated layer or a Zn-Mg-Al-Si based alloy plated layer is formed on the surface of the steel sheet, and the surface is provided with a film layer as a substrate treatment layer containing 100 pts.mass water-based resin as a solid content and 0.2 to 50 pts.mass tannin or tannic acid, and the surface is provided with a film of a 0.2 to 5μm film thickness obtained by applying and baking a water-based lubricating coating material containing (a) an ether ester type urethane resin having a bisphenol type skeleton, an ester skeleton, and a carboxyl group, and (b) an epoxy resin so that the total of (a+b) is controlled to 50 to 85 mass% to the total solid content, (c) 3 to 30 mass% polyolefin wax and (d) 10 to 40 mass% silica having a grain diameter of 3 to 30 nm.
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