Abstract: An optical recording medium comprises a substrate, a recording layer overlying the substrate in a manner such that it is not present at the inner and outer peripheral portions of the substrate, a metal reflective layer overlying the recording layer in a manner such that the inner periphery of the metal reflective layer is coterminous with that of the recording layer while the outer peripheral portion of the reflective layer extends over the outer perphery of the recording layer, and a protective layer wholly covering the metal reflective layer extending over the recording layer, both at the inner and outer peripheral portions. The optical recording medium exhibits an excellent adhesion strength of the protective layer even when stood under high humidity and high temperature conditions for a long period of time, and the protective layer is not peeled off when subjected to a tape peeling test.

Abstract: An optical recording medium comprises a substrate, a recording layer overlying the substrate in a manner such that it is not present at the inner and outer peripheral portions of the substrate, a metal reflective layer overlying the recording layer in a manner such that the inner periphery of the metal reflective layer is coterminous with that of the recording layer while the outer peripheral portion of the reflective layer extends over the outer periphery of the recording layer, and a protective layer wholly covering the metal reflective layer extending over the recording layer, both at the inner and outer peripheral portions. The optical recording medium exhibits an excellent adhesion strength of the protective layer even when stood under high humidity and high temperature conditions for a long period of time, and the protective layer is not peeled off when subjected to a tape peeling test.

Abstract: An optical recording medium of a single plate type comprises a substrate having a groove, a recording layer containing a dye overlying the substrate, a reflective layer overlying the recording layer and a protective layer overlying the reflective layer, wherein the recording layer is formed by a spin-coating method and the dimension of the groove varies from the center portion of the substrate toward the outer periphery thereof.

Abstract: An optical recording medium of a single plate type comprises a substrate, a recording layer overlying the substrate, a reflective layer overlying the recording layer, and a protective layer overlying the reflective layer, the recording layer being produced by coating a nonpolar solvent-soluble substituted phthalocyanine dye in a nonpolar solvent and the nonpolar solvent content of in the recording layer being 5% by weight or less.

Abstract: A formation process of an amorphous silicon film, which process comprises subjecting a higher silane containing at least two silicon atoms to photochemical decomposition under radiation of a light having a wavelength of 300 nm or shorter so as to cause amorphous silicon to deposit on a substrate.