| 摘要 |
PURPOSE:To make recession and protrusion defects such as bulge dents be not remarkable, and avoid virtually the occurrence of an appearance defect by performing blast treating or etching working on sidewall molding surfaces after machining, and also performing hard chrome plating thereon, and thus forming it into a specific surface roughness. CONSTITUTION:Members except a tread segment 9 are formed by the use of a steel mold material such as a mechanically structural carbon or the like. A tire molding surfaces (sidewall molding surfaces 6A, 6B, bead molding surfaces 8A, 8B, tread molding surface 9A) are smooth-worked by machining such as cutting or grinding into a surface roughness of R maxl.6S-6.3S, and the sidewall molding surface 6A, 6B are given further blast treating and worked into a satin finish of the order of 16S-25S. And, blast treated sidewall molding surfaces 6A, 6B and bead molding surfaces 8A, 8B are given hard chrome plating and a plated film of the order of 20-30mum is formed thereon. Inasmuch as a plated film is formed approximately uniformly along the surfaces, the surface roughness after the blast treating is almost kept after plating. |
