INJECTION MOLD FOR OPTICAL DISK

摘要

PROBLEM TO BE SOLVED: To form an optical disk having small double refraction even at the outer periphery by holding the injection molding temperature of a mold part corresponding to an annular area set out of the outer peripheral area of a cavity from the intermediate area of the disk to be molded in the cavity in a predetermined temperature range. SOLUTION: Temperature regulating means is constituted by providing a plurality of annular passages 3 for passing temperature regulating liquid in the stationary mold part 1 and the movable mold part 2 of an injection mold corresponding to annular area in a flat surface shape set to the area near the outside from the outer peripheral area of a cavity 6 from the intermediate area of an optical disk to be molded in the cavity 6 of the mold. Temperature regulating liquid is supplied to the plurality of passages 3 from a temperature regulating liquid supply source thereby to regulate the temperature of the mold as desired.