| 摘要 |
PURPOSE:To suppress warpage of a disk substrate as small as possible by using UV-curing epoxy resin for a coating material of a disk substrate. CONSTITUTION:Overcoat layers 5, 6 are formed by using epoxy resin which reacts and solidifies by the polymn. mechanism of open-ring polymn., which is completely different from the reaction mechanism of UV-curing acrylate resin. Namely, on a plate substrate 1 comprising resin material and having an information structure in one side thereof, there are formed an information recording layer comprising plural layers of inorg. layer 2, recording layer 3 and inorg. layer 4. The recording layer side or both sides of the substrate 1 are covered with the overcoat layer 5, 6 essentially comprising epoxy resin which can be cured with UV ray or thermal radiation. Thereby, volume contraction during curing can be extremely suppresed to avoid warpage of the disk. |
