METAL MOLD FOR INJECTION MOLDING TUBULAR OR COLUMNAR PRODUCTS AND MOLDED PRODUCT OBTAINED BY USING SAME

摘要

A metal mold for injection molding tubular or columnar products is provided in which the portions of matching surfaces of metal mold members which are close to end portions of an annular or cylindrical cavity are provided with grooves extending continuously or intermittently so as to surround said end portions of said annular or cylindrical cavity.