COATING TYPE PHOSPHATE TREATED STEEL SHEET EXCELLENT IN LUBRICITY AND COATING MATERIAL ADHESION, AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To produce a coating type phosphate treated steel sheet reduced in the exhaustion of harmful matters produced at the time of the production, excellent in lubricity and adhesibility to coating materials and good in corrosion resistance. SOLUTION: A phosphate film in a phosphate treated steel sheet in which the phosphate film is formed on the surface of a steel sheet or a galvanized steel sheet satisfies the conditions of (1) the coating weight(W) of the phosphate film is 0.2 to 10 g/m2, (2) the peak intensity(I) in the [020] plane of hopheite by X-ray diffraction satisfies the inequality 100×W<=I<=1500×Wcps and (3) alkali soluble content is <=0.8 Wg/m2.