| 摘要 |
PURPOSE:To prevent the deterioration and deformation of a substrate occurring in the heat of a laser beam and to remarkably improve an information rewritable characteristic by using a thermosetting resin substrate (substrate consisting of a thermosetting resin layer/glass substrate). CONSTITUTION:The substrate of an optical disk is constituted of the thermoset ting resin substrate 1 and optical guide grooves are formed on the surface thereof. A thin film 2 of an optical recording medium is formed on the thermo setting resin substrate 1 and a protective film 3 is formed thereon. An epoxy resin, melamine resin, etc., are usable for the thermosetting resin of the optical disk and more particularly the epoxy resin is preferable in terms of transpar ency, moldability, strength and heat resistance. The strength over the entire part of the substrate is improved and a material (resin layer) to permit easy formation of patterns is usable if the substrate is constituted of the heat resist ant substrate and the thermosetting resin layer thereon in place of constituting the substrate of only the thermosetting resin substrate. An alloy consisting of elements of >=2 components to exhibit an eutectic phenomenon or materials having compd. compsn. and, for example, In-Sb, Al-Ca, etc., are used for the material to constitute the optical recording medium film. |
