| 摘要 |
PURPOSE:To obtain the rubber roller having fine surface roughness and sufficient viscosity without requiring a powder applying stage by winding sponge rubber on an arbor and expanding the rubber within the mold provided with ruggedness on the inside surface in contact with the sponge rubber, then vulcanizing the rubber. CONSTITUTION:The ruggedness 11a is provided by a method, such as sandblasting or honing, on the inside surface of the mold 11 in contact with the rubber roller 12. The rubber roller 12 is first put into an electric furnace and is subjected to primary vulcanization. The metallic flask and mold are taken out of the finished product of the primary vulcanization and the stains in an expanding pipe are removed; thereafter, the rubber roller 12 is put into the electric furnace and is subjected to secondary vulcanization. The rubber expands until the rubber comes into contact with the inside surface of the mold 11 and a spacing S is generated with the ruggedness 11a on the inside surface of the mold when the rubber roller 12 is expanded in this stage. This spacing S acts as a route G for exhalating the gases generated at the time of the expansion molding and, therefore, the gas passages, such as grooves, are not formed on the surface of the roller 12. The mold parting after the molding is facilitated and the smoothness of the rubber surface is assured without using the powder. |
