Corrosion, powdering resistance, after painting distinctness of image, pre-primed steel sheets having excellent coating properties and adhesion

摘要

PURPOSE: To provide a preprimed steel sheet with excellent corrosion resistance, powdering resistance, brightness of reflectivity after coating, coating property and adhesive property which is used by applying intercoating and topcoating or only topcoating without applying electrodeposition coating after forming work. ;CONSTITUTION: A chromate film of a prescribed amount of adhesion is formed at least on one side of a galvanized steel sheet. A resin film having a film thickness (solid content) of 1.0-30m, desirably 3.0-20m is formed as the upper layer thereof. The resin film is constituted by blending 0.1-30 pts.wt. solid lubricant with 100 pts.wt. basic resin consisting of at least one kind of an epoxy- based resin selected from among an epoxy resin, a modified epoxy resin and a polyhydroxypolyether resin and adding a rustproof additive consisting of silica and/or hardly soluble chromate at the rate of 99/1-50/50 by weight ratio to the basic resin in accordance with necessity.;COPYRIGHT: (C)1996,JPO