| 摘要 |
PURPOSE:To enhance the close adhesiveness of the inorg. membrane formed on the surface of a disk by applying a plastic film to the inner wall surface of the cavity of a mold and injecting a molten resin into the cavity to obtain a disk substrate. CONSTITUTION:A plastic film 3 becoming a skin layer is inserted in the gap between the fixed part 1 and movable part 2 of a mold when the movable part 2 of the mold is opened by driving a roll and confined in the mold by closing the mold. A resin becoming a core part is injected into the mold through an injection nozzle and subsequently cooled, solidified and released to form a disk substrate. Therefore, by appropriately optimizing the characteristics of the plastic film 3 becoming the skin layer, the close adhesiveness with an inorg. membrane can be improved to a large extent and the warpage of a recording disk can be eliminated. |
