| 摘要 |
This invention provides an organic multicoated steel sheet susceptible to cationic electrodeposition coating which comprises a zinc or zinc alloy plated steel sheet and as a first layer provided on the surface of said plated steel sheet a sparely soluble chromate film of 1-30% in water soluble matter, 0.01-1.0 in Cr6+/Cr3+ ratio and 10-150 mg/m2 in total chromium application amount on one surface and as a second layer provided said first layer a solid film having a thickness of 0.3-5 mu m of a solvent type coating composition having the following composition based on the weight of non-volatile matter: (a) 30-90% of an urethanated epoxy ester resin having a number-average molecular weight of 300-100,000, (b) 5-40% of a hydrophilic polyamide resin having a polymerization degree of 50-1,000 (c) 5-40% of a silica particle of 1-100 m mu in average particle size and (d) 1-20% of a polyethylene wax having a molecular weight of 1,000-10,000. |
