TIN-PLATED STEEL PLATE AND PROCESS FOR PRODUCING THE TIN-PLATED STEEL PLATE

摘要

A tin-plated steel sheet includes an Sn-containing plating layer in which the mass per unit area of Sn is 0.05 to 20 g/m 2 and which is disposed on at least one surface of the steel sheet; a first chemical conversion coating which contains P and Sn, in which the mass per unit area of P is 0.3 to 10 mg/m 2 , and which is disposed on the Sn-containing plating layer; and a second chemical conversion coating which contains P and Al, in which the mass per unit area of P is 1.2 to 10 mg/m 2 and the mass per unit area of Al is 0.24 to 8.7 mg/m 2 , and which is disposed on the first chemical conversion coating. The steel sheet can suppress a degradation of appearance and a reduction in paint adhesion caused by the oxidization of the tin-plated surface without using Cr and can be subjected to chemical conversion treatment at low cost.