DISC-LIKE PLASTIC MOLDING AND METHOD FOR FORMING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a disc-like plastic molding capable of improving an accuracy of the molding while preventing an increase in a die cost and a decrease in a working efficiency of a forming work. SOLUTION: The disc-like plastic molding comprises a disc-like state formed by injecting a molten resin in a mold cavity from a plurality of pin gates formed in the mold and transfer parts 14 and 15 formed at least any of an outer peripheral side and an inner peripheral side of a disc-like body 13. The molding also comprises a plurality of shrinkage recesses 17 in which the inner peripheral surface shape of the cavity is not transferred and which are radially arranged on a side face 16 of the body 13. A wavy rugged part can be prevented from being formed at the parts 14 and 15 of the outer peripheral side and the inner peripheral side of the body 13 by forming the recesses 17, and the disc-like plastic molding having a high roundness accuracy of the parts 14 and 15.