Patent ID: 6716374
Filing Date: 2004-04-06
Classification: B29C,B29L,Y10S

Abstract:
A method for compression-molding an optical disk substrate, wherein molten resin is injected into a cavity between a stationary mold and a movable mold and molded into a desired shape by compressing the resin between the stationary mold and the movable mold, comprising:moving the movable mold from an initial position to a first position where no clamping force is generated between the stationary mold and the movable mold; injecting molten resin into the cavity between the stationary mold and the movable mold; moving the movable mold to a second position where a clamping force is generated between the stationary mold and the movable mold by positioning control of the movable mold; switching the positioning control of the movable mold to clamping force control upon detection of the movable mold having reached the second position; moving the movable mold to and maintaining same at a third position by the clamping force control, so that the clamping force generated between the stationary mold and the movable mold reaches a first target value, wherein the speed of the movable mold is regulated in accordance with a difference between a target clamp pressure value and the clamping force being applied; switching the clamping force control to the positioning control upon detection of the clamping force having reached a second target value which is lower than the first target value; and returning the movable mold to the initial position by the positioning control.