| 摘要 |
PURPOSE:To obtain an optical disc substrate which shows satisfactory group or pit transfer properties. CONSTITUTION:A molding resin is completely filled within 0.35sec., and at the same time, the non-dimensional temperature THETA-(Tg-Tmo)/(Tme-Tmo) which is determined by a molding resin glass transition temperature Tg, and a die temperature Tmo and a resin temperature Tme during injection molding, should be 0.02<=THETA<=0.1, if the resin is molded, in an optical disc substrate having a narrow track pitch or land width. Consequently, it is possible to obtain the optical disc substrate having satisfactory group and pit transferability and excellent signal properties. |
