| 摘要 |
PURPOSE:To enable gas to be exhausted out of the gap between the side wall molding surface of a mold and a tire surface by making the side wall molding surface into a specific surface roughness after machine work by a blast treatment or an etching process. CONSTITUTION:The tire side wall molding surfaces 2A, 3A of the upper mold 2 and lower mold 3 of a vulcanizing mold 1 are molded into Rmax.6S-20S in its surface roughness by machine work and buff finish, and thereafter blast work or etching work is performed therefor in order to make them into a fine matte finish of Rmax.26S-35S in its surface roughness. Herein, the Rmax.26 S is the minimum value necessary for securing a gas conduit and Rmax.35S is the limit value by which unvulcanized rubber is not likely to flow into the fine recessed parts of the mold surface. On the upper mold 2 and lower mold 3, exhausting flow conduits 7, 8 are respectively formed that is formed by the fine recessed and protruded parts and communicate to the exhausting flow conduits. Gas is smoothly exhausted from the exhausted conduits and thus the rubber layer of the side wall can be rendered thin, resulting in enabling the tire surface to be finished into fine matte patterns. |
