SURFACE-TREATED TIN-PLATED STEEL SHEET AND SURFACE TREATMENTSOLUTION

摘要

The present invention provides a surface-treated tin-plated steel sheet which comprises (1) an alloy layer on a surface of a steel sheet; (2) a tin-plated layer which is provided on the alloy layer so that the alloy layer is exposed at an areal rate of 3.0% or more; and (3) a film comprising P and Si as coating weight of 0.5 to 100 mg/m<2> and 0.1 to 250 mg/m<2>, respectively, provided on the exposed portions of the alloy layer and the tin-plated layer. In addition, a chemical conversion solution which contains phosphate ions, tin ions, and a silane coupling agent and which has a pH of 1.5 to 5.5 is also provided for obtaining the surface treated steel sheet described above. The surface-treated tin-plated steel sheet of the present invention has superior paint-adhesion characteristics, corrosion resistance after coating, antirust properties, and workability without containing chromium which is unfavorable in environmental conservation.