CHROMIUM-FREE RESIN SOLUTION COMPOSITION HAVING GOOD ALKALINE RESISTANCE AND FORMING PROPERTY, METHOD FOR SURFACE TREATING STEEL SHEET USING THE SAME, AND SURFACE-TREATED STEEL SHEET

摘要

PPROBLEM TO BE SOLVED: To provide a resin solution composition for surface treating a steel sheet having good corrosion resistance, alkaline resistance, forming property, electrical conductivity and chemical resistance, and containing no chromium component at all, and to provide a method for producing a steel sheet using the same, and to provide a surface-treated steel sheet produced therefrom. PSOLUTION: The surface of a cold rolled steel sheet, a galvanized steel sheet or the like is coated with a resin solution composition containing a mixture of a soft urethane-based resin and a hard urethane-based resin, a Ti- or Zr-based organic oxide and one or more kinds of compounds selected from among aluminum monophosphate, aluminum dihydrogenphosphate, primary zinc phosphate and hydrated manganese phosphate, and a solvent at the coating weight of 300 to 1,800 mg/mSP2/SP. PCOPYRIGHT: (C)2009,JPO&INPIT