| 摘要 |
<p>PURPOSE:To manufacture a black-color steel plate excellent in welding property and blackness by depositing a chromate film of specified chromium build-up amt. on the surface of a zinc-alloy plating, and incorporating a specified amt. of black dye into a water-dispersible thermosetting resin and then applying this resin. CONSTITUTION:A chromate film is formed on the surface of a zinc-plated or zinc alloy-plated material to 10-200mg/m<2> chromium deposition (metal chromium), on which a coating material of following compsn. is applied to form a black coating film of 0.3-3mum thickness. This coating material consists essentially of a water-soluble or water-dispersible thermosetting resin and contains 1-200 pts.wt. of water-soluble black dye to give black color to 100 pts.wt. of this base resin. Since the formed black film is thin, the steel sheet can be welded and has excellent blackness.</p> |
