| 摘要 |
PURPOSE:To form a coated film having excellent corrosion preventiveness in an edge part and resistance to filiform rust by coating a cation paint contg. a pigment having a specific oil absorption by electrodeposition on a material to be coated, then coating a paint having a specific min. electrodeposition current density by electrodeposition thereon. CONSTITUTION:The cation paint I is prepd. by consisting the same of a resin A and at least 5wt% pigment B having >=100 oil absorption and compounding the same in such a manner that the total oil absorption of the pigment B attains 1,000-10,000 per 100g resin A. The first electrodeposition painting is executed by using the above-mentioned paint I and making the material to be coated as a cathode. On the other hand, the emulsion cation type electrodeposition paint II which consists of a resin C and a pigment D having the total oil absorption smaller than the total oil absorption of the above-mentioned paint I and has <=0.7mA/cm<2> min. electrodeposition current density and >=80% degree of emulsification is prepd. The paint II in the uncured state is coated by electrodeposition in the second time after the above- mentioned 1st electrodeposition painting. The electrodeposition coated film is thereafter cured by heating to form the composite cured and coated film. The coated film having the excellent corrosion resistance of the material to be coated, more particularly the corrosion resistance of the edge part, resistance to filiform rust and smoothness of the coated surface is thus obtd.
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