| 摘要 |
PURPOSE: To obtain a good double refractive index and to shorten a molding cycle time in molding a disk substrate enhanced in mechanical characteristics. CONSTITUTION: The movable mold and fixed mold of a mold for a disk substrate are respectively attached to the movable plate and fixed plate of a molding machine and, when the movable mold is moved toward the fixed mold so as to leave a predetermined distance of 0-0.5mm by mold clamping operation moving the movable plate through a mold clamping cylinder, injection filling is started and, at the time of the completion of mold clamping, the oil pressure applied to the mold clamping side of the mold clamping cylinder is adjusted to hold mold clamping force to the predetermined value corresponding to about 10-40% of rated mold clamping force. After the completion of the injection process, mold clamping oil pressure is raised to perform not only the control of mold clamping force of one stage or a plurality of stages but also a molten resin cooling process. |
