| 摘要 |
PROBLEM TO BE SOLVED: To prevent a crease, a dent, etc., from being generated or a surface in a shell reinforced layer obtained by injection molding thermoplastic resin on a rear surface of a container-like inner surface layer material obtained by two step hot forming of a synthetic resin sheet, the thermoplastic resin is nonexpanded, or an expansion magnifying power is adjusted at a specific number or under. SOLUTION: A cast acrylic sheet 1 being a synthetic resin sheet is placed on a vacuum forming mold (female mold) 2 of a vacuum forming machine, its periphery part is clamped with a clamp material 3, a cast acrylic sheet 1 is softened by heating, and sucked by a, vacuum in the arrow A direction. After cooling, the clamp material 3 is taken off, and a container-like inner surface layer raw shape material 4 is extracted from the female die 2 in the arrow B direction. The thermoplastic resin is adjusted to a foam of under 1.1 expansion magnifying power which is solid or near solid, and when a rear surface of the inner surface layer raw shape material is lined by injection molding, since it is held with a large heat capacity of the resin and injection pressure, the inner surface layer raw shape material is fixed by pressure onto a male die of the injection molding mold, and the highly precise inner surface material layer of the same dimension as designed one is obtained. |
