| 摘要 |
PURPOSE:To effectively cure an expanded molding with a high dimensional accuracy by a method in which an expanded polypropylene resin molding in molds is cured in a proper curing temperature range according to the densities of the expanded moldings. CONSTITUTION:Expansible grains are packed into molds and heated to form an expanded polypropylene resin molding in which grains are mutually bonded. The expanded polypropylene resin molding is cured at a temperature of 40 deg.C to 2,000d+40 deg.C when the density (d) of the expanded molding is 0.03g/cm<3> or less and also at a temperature of 40-100 deg.C when the density is 0.03g/cm<3> or more. Since the expanded molding is cured at proper temperatures according to the densities, the shrinkage of the molding cn be prevented, the shrinkage after molding can be recovered, and the expanded molding with high dimensional accuracy can be obtained without the needs for heat energy more than necessary and also without troubles with shortage of curing. |
