Patent ID: 6068906
Filing Date: 2000-05-30
Classification: B29C,G11B,Y10S,Y10T

Abstract:
A disc substrate molding metal mold apparatus adapted for molding synthetic resin material to carry out molding of a disc substrate of an information signal recording medium,the metal mold apparatus comprising a first metal mold serving as the fixed side and a second metal mold serving as the movable side which are adapted so that they are butted to each other to constitute a molding portion for carry out molding of the disc substrate,temperature controlling means for controlling the temperature of the first metal mold and the second metal mold, said temperature controlling means controlling a temperature of the metal molds to a level not lower than (Tg-24).degree. C. when the synthetic resin material is cooled and solidified,wherein a smoothing layer of metal is integrally formed at the molding plane surface side of at least one of the first and second metal molds and wherein Tg is the glass transition temperature of the synthetic resin material.