| 摘要 |
PURPOSE:To provide properties fitted to use and to reduce the generation of warpage, in injecting a foamable resin material between upper and lower metal plates and heating both metal plates to forma said resin material, by differentiating the material qualities and heating temps. of the upper and lower metal plates. CONSTITUTION:The metal hoop materials 5, 6 supplied from pay-off reels 7, 8 are molded by molding rolls 9, 10 so as to be bent at both end parts and subsequently preheated to 20 - 50 deg.C in a preheating chamber 11 and, thereafter, a foamable resin material is injected between the metal hoop materials 5, 6 by an injection apparatus 12 and foamed during the movement between double conveyors 13 to form a heat insulating plate material 4 wherein the space between the metal hoop materials 5, 6 is filled with a foamed resin layer 3. When the foamable resin material is foamed, the difference between the heating temps. of the metal hoop materials 5, 6 is set to 20 deg.C or less and both metal plates are heated to 20 - 70 deg.C but the metal hoop material having a smaller coefficient of linear expansion among the metal hoop materials is heated to higher temp. The formed heat insulating plate material is gradually cooled and the metal hoop materials 5, 6 are contracted but, since heating temp. difference is provided, the warpage of the heat insulating plate material is suppressed. |
