| 摘要 |
PURPOSE:To obtain an excellent molded item having accurately formed corners by a method wherein a sheet is brought into close contact with a mold, which produces the side with the sheet adhered thereto of the item, and at the same time said mold is cooled due to the vaporization of the water and adiabatic expansion of the steam in the steam chamber of said mold by vacuumizing said steam chamber just after the foam molding by heating. CONSTITUTION:An impact-proofing polystyrene resin sheet 5 is installed onto the inner wall 3a of the female mold 3 of a mold assembly 1 and, after that, brought into close contact with the inner wall 3a by vacuumizing the steam chamber 6a of the mold 3. Next, pre- expanded polystyrene resin particles 8 are charged into a cavity 7, which is formed by clamping the molds 2 and 3 together, so as to heat the molds after the pressure in the mold is brought back to the atmospheric pressure so as to obtain a foam-molded product. After that, the pressures in the steam chambers 6a and 6b are brought to the atmospheric pressure and, after that the chamber 6a is vacuumized so as to bring the sheet 5 into close contact with the inner wall 3a and at the same time cool the chamber 6a by vaporizing the water and adiabatically expanding the steam in the chamber 6a. Simultaneously, the chamber 6b of the mold 2 is also vacuumized so as to cool it. After that, the interiors of the chambers 6a and 6b are cooled and finally a molded item is taken out of the mold assembly. |
