| 摘要 |
<p>Described herein is a method for producing a resin-coated rust-proof steel sheet with properties suitable for electrodeposition coating, the method including the step of, prior to chromate treatment and resin coating, immersing a zinc- or zinc alloy-electroplated steel sheet in an acid bath containing at least one member selected from the group consisting of sulfuric acid, chloric acid, phosphoric acid, boric acid and nitric acid and salts thereof and having a pH value smaller than 6, inclusive, to remove a surface layer of the electroplating on said steel sheet, thereby activating the plated surface in such a manner as to improve the quality of the following chromate treatment. Advantageously, the method further includes the step of grinding the electroplated surface with a brush or roll containing fine abrasive grains of #200 or a higher number to remove said surface layer simultaneously with or separately from the immersion in the acid bath.</p> |
