| 摘要 |
PROBLEM TO BE SOLVED: To obtain a black coating composition which can give a coating film having a sufficient degree of blackness and excellent rust-preventive properties when used in dip coating by mixing a modified epoxy resin with a zinc powder, carbon black and fine black iron oxide particles. SOLUTION: A urethane-, acid- or amine-modified epoxy resin in an amount of 100 pts.wt. having a weight-average molecular weight of 5,000-50,000 is mixed with 150-400 pts.wt. zinc powder having a means particle diameter of 2.0-10.0μm, 5-30 pts.wt. carbon black having a pH of 2.0-11.0 (JIS K-6221), 10-100 pts.wt. fine black iron oxide powder having a particle diameter of 5μm or below and optionally 5-50wt.%, based on the solid component, of the modified epoxy resin, phosphomolybdate or phosphate, and the obtained mixture is dispersed in at least one solvent selected among xylene, toluene and polyhydric alcohols. Thus composition can give a coating film which itself can serve as a top coating film and, when top-coated, the top coating is effective to make the defects such as deterioration or peeling difficulty discernible.
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