PURPOSE: To obtain a material for a can having corrosion resistance equal to more than that of an aluminum can and capable of simplifying a can manufacturing process by providing a broken part to the alloy layer of a steel plate having an aluminum or aluminum alloy film through the alloy layer and providing a chromium compound film and a specific polyester resin film to said broken part.
CONSTITUTION: After a cold rolled steel plate having a thickness of 0.35mm is annealed on a molten aluminum plating line, aluminum plating is applied to the single surface of said steel plate. Next, this steel plate is subjected to cold rolling at a draft of about 25% and an iron-aluminum intermetallic bond is formed to the broken part of an alloy layer to impart close adhesiveness capable of withstanding DI processing. Subsequently, a chromium compound film consisting of metal chromium 30mg/m2 and chromium hydroxide 20mg/m2 is formed to the steel plate in a bath based on chromic acid by an electrolytic method and, further, a polyester resin film wherein heat of cold crystallization is 7 cal/g or less and/or heat of fusion is 10 cal/g or less and density is 1.38 or less is laminated to said film on the same line. The obtained composite steel plate has excellent DI moldability and corrosion resistance.
HAYASHI TOMOHIKO
NISHIDA HIROSHI
TANIMURA KOJI
