| 摘要 |
PURPOSE:To reduce a necessary amount of steam by a method wherein the cavity sides of inner molds are covered with semi-insulating layers and the outsides of the inner molds are covered with insulating layers while a multitude of steam introducing fine holes penetrating those layers is provided and further cooling pipes are embedded in the walls of the inner molds. CONSTITUTION:In the metallic inner molds 11, 11' provided in a steam chamber for forming the cavity for expanding and molding the expandable thermoplastic resin, the surfaces of the inner molds which are contacting with the resin are covered with semi-insulating layers 16, 16' (for example; epoxy resin, phenolic resin, butyl rubber or the like) and the steam chamber side surfaces 17, 17' thereof are covered with the insulating layers 18, 18' while a multitude of steam introducing fine holes 20, 20' penetrating the semi-insulating layers, the inner molds and the insulating layers is provided and further the cooling pipes 14, 14' are embedded in the walls of the inner molds 11, 11'. |
