| abstract |
A rubber composition for recovering releasability from compression molds. The composition is used to impart releasing properties to a mold surface after a fouling substance resulting from the step of molding a curable resin has been removed from the mold surface. The composition contains, as a base resin, an unvulcanized rubber comprising an ethylene/propylene rubber and a butadiene rubber in a proportion of from 90/10 to 50/50 by parts by weight, and contains a specific release agent. The unvulcanized rubber is an unvulcanized rubber which, after having been vulcanized and cured, has an elongation of 80-800%, a tensile strength of 3-10 MPa, and a rubber hardness (durometer hardness) of A60 to A95, and which has a 90% vulcanization time as measured at a mold temperature of 175 DEG (proper vulcanization point), tc(90), in the range of 50-100 sec or 200-400 sec. |