| 摘要 |
PURPOSE:To improve the sticking property of a protective layer to a reflecting layer, to enhance the mechanical strength of the protective layer and to increase the number of repetitions of overwriting. CONSTITUTION:A first protective layer 2, a recording layer 3, a second protective layer 4, a reflecting layer 5 and a third protective layer 6 are successively laminated on a substrate 1 for an optical disk to form a phase change optical disk. In this case, the first and second protective layers 2, 4 are especially made of a mixture of ZnS.SiOx (2.0>x>1.0) with Y2O3. Since this Y2O3 can be allowed to act as a binder, the above-mentioned purpose can be attained. |
