| 摘要 |
PURPOSE:To prevent deformation of a substrate by adjusting the water absorption quantity of a protective layer provided on the substrate on the side opposite to a side where a recording layer is provided. CONSTITUTION:The recording layer is provided is provided directly or via an under coat layer consisting of an ionomer resin or the like which has good adhesiveness and acts as a barrier for water and gases on the substrate which is formed of polyester, etc., and has, for example, 0.02-0.15mm thickness. This recording layer is to be recorded with information by the optical change generated by irradiation of laser light and is formed by using a polymethine dye, etc. The 1st protective layer consisting of the same material as the material of the under coat layer is provided directly or via the intermediate layer consisting of the same material as the material of the under coat layer on this recording layer. The 2nd protective layer is provided on the substrate on the side opposite to the side where the recording layer is provided and the water absorption quantity thereof is adjusted, by which the deformation of the disk is prevented. |
