| 摘要 |
PURPOSE:To obtain an optical disk having high transparency, low double refraction, low water absorption, high heat distortion characteristic, and permitting reading of data with less error by equalizing the refractive index of a layer of thermosetting resin to the refractive index of a layer of photosetting resin. CONSTITUTION:In a substrate for an optical disk comprising a layer of an optically transparent thermoseting resin and an adjacent layer of a photosetting resin, the refractive index of the thermosetting resin layer is made equal to the refractive index of the photosetting resin layer. The photosetting resin having the same refractive index as the thermosetting resin layer is spin-coated on a formed plate material obtd. by thermally setting the thermosetting resin, and the photosetting resin is cured optically by mounting a stamper thereon and radiating light from the formed plate side. By this process, there is no fear for causing refraction and/or irregular reflection at the interface of the both layers, nor generating error in the reading of data. |
