ORGANIC COMPOSITE CLAD STEEL SHEET EXCELLENT IN CORROSION RESISTANCE AND ITS PRODUCTION

摘要

PURPOSE: To inexpensively produce an organic composite clad steel sheet excellent in corrosion resistance by forming a Cr oxide layer on the surface layer of a Zn-Cr allay plated layer with a specified compsn. provided on the surface of the steel sheet and providing a resin layer contg. silica on the upper layer. CONSTITUTION: At least one face of a steel sheet is electroplated with a Zn-Cr allay contg. 5 to 20wt.% Cr by 1 to 30g/m<2> coating weight. Next, this Zn-Cr allay plated layer is subjected to surface oxidation to form a Cr oxide layer in which Cr is oxidized over 0.01 to 0.1μm thickness on the surface layer. Moreover, on the upper layer, a resin layer contg. about 20 to 60 pts.wt. silica and organic high polymer resin such as epoxy resin is formed by 0.2 to 1.5g/m<2> .