| 摘要 |
PURPOSE:To obtain a foamed polyolefin resin molding unit which produces extremely less pinhole and irregular surface by filling polyolefin resin preliminary foamed particles in a mold, heating and foaming, fusion-bonding among the particles as the foamed molding unit, applying an internal pressure larger than the atmospheric pressure to the molding unit and then heatng to foam in the molds of substantially the same shape and size. CONSTITUTION:The primary foaming step of filling preliminary foamed polyolefin resin particles in a mold, heatig, foaming of fusion-bond among the particles to obtain the foamable molding unit, and the secondary foaming step of pressuring the molding unit obtained in the primary foaming step to apply an internal pressure larger than the atmospheric pressure and then heating to foam the molding unit in the molds of substantially the same shape and size are provided. Thus, the disadvantages of the foamed polyolefin resin molding unit which feasibly occurs in the irregularity of the thickness due to the pinhole or irregular surface are eliminated, thereby manufacturing the foamed polyolefin resin molding unit having preferable physical properties. |
