SURFACE-TREATED STEEL PLATE COATED WITH DIFFERENT KIND OF SURFACE AND BACK FILMS

摘要

PROBLEM TO BE SOLVED: To provide a surface-treated steel plate capable of satisfying required characteristics contrary to each other by providing a different kind of surface and back films. SOLUTION: The single surface of a steel plate is treated with an org. polymer emulsion prepared by stably dispersing an org. polymer being a resin containing 0.5-2 wt.% of a lubricant and containing an ethylenic unsaturated carboxylic acid component or/and a hydroxyl group component in the total amt. of 10 wt.% or more and the remainder of inevitable impurities in an aq. medium and the other surface thereof is treated with an org. polymer emulsion prepared by stably dispersing an org. polymer being a resin containing 0.5-20 wt.% of a lubricant and containing an ethylenic unsaturated carboxylic acid component or/and a hydroxyl group component in the total amt. of below 10 wt.% and the remainder or inevitable impurities in an aq. medium. A different kind of the surface and back compsn. films thus formed are applied to the steel plate in a thickness of 0.5-5μm per the single surface thereof.