| 摘要 |
PURPOSE:To obtain an optical disc mold of excellent adherence between a stamper and the movable side, by a method wherein the mirror-finished part of either one with which the stamper is provided so as to go along, of the fixed side or the movable side is magnetized. CONSTITUTION:A mirror plate 5 is magnetized with the preferable magnetic flux density of about 60 Gauss. As for the materials for the mirror plate 5 and for a stamper 6, any magnetic material can be employed fittingly. However, normally, Ni is used as the material for the stamper 6. When the stamper 6 is intended to be mounted to the mirror plate 5, firstly movable side fixing ring 8 and a holder 11 are dismantled from the force side part 4 of a mold. Secondly, the stamper 6 is attracted to the mirror plate 5. Thirdly, the holder 11 and movable side fixing ring 8 are respectively fitted to a mounting hole 9 and an annular groove 7. After the injection and solidification of resin, the hydraulic cylinder is operated so a fixed plate 1 and the fixed side 2 of the mold are parted so as to take a sprue out of the mold and, after that, to cut off the sprue by advancing a punch 12 by means of a hydraulic cylinder. |
