THERMOPLASTIC RESIN STRUCTURE

摘要

PROBLEM TO BE SOLVED: To enable the fusion and the regeneration to be easily made for use after the mere grinding process by forming a three-tier structure of a pliable skin material layer, a a pliable foaming material layer and a hard base material layer, then forming each layer of the three-tier structure of a mutually fusible and adhesive thermoplastic resin and molding a pliable foaming material layer by an injection foam molding process. SOLUTION: When a ribbed box-type structure is manufactured, a pliable skin material layer 1 obtained by cutting a pliable skin material layer material along the shape of a mold top face is attached to the movable half of a mold, and a hard base material layer 2 which is previously molded is attached to the fixed half of the mold. Next these halves of the mold are clamped, then a pliable foaming material layer material is injected into a void generated between the pliable skin material layer 1 and the hard base material layer 2 and packed to be formed into a pliable foaming material layer (an unfoamed state). After the primary cooling, the movable half of the mold is transferred to adjust the wall thickness of the top plate part and the pliable foaming material layer material is caused to foam simultaneously with the transfer of the movable half of the mold to form a pliable foaming material layer 3b. After that, a molded product is unloaded after the secondary cooling while the mold is retained as it is at its position.