ENVIRONMENTALLY FRIENDLY STEEL SHEET FOR CONTAINER MATERIAL, PROCESS FOR PRODUCING THE SAME, AND ENVIRONMENTALLY FRIENDLY LAMINATED STEEL SHEET FOR CONTAINER MATERIAL AND PRECOATED STEEL SHEET FOR CONTAINER MATERIAL EACH PRODUCED FROM THAT STEEL SHEET

摘要

A laminated steel sheet for container materials or a precoated steel sheet for container materials. The steel sheets each is characterized by comprising a steel sheet, a tin layer or iron-tin alloy layer formed on the steel sheet, a tin oxide layer which is present on the tin or alloy layer and has a thickness as measured by the electrolytic removal method of 0-3.5 mC/cm, and a chromium-free primer layer for adhesion enhancement which is formed on the oxide layer and which comprises a zirconium compound and contains neither fluorine nor nitrate nitrogen, the amount of the primer layer film being 1-30 mg/min terms of zirconium amount, the content of sulfuric acid radicals (SO) therein being 0-7 mg/m.