| 摘要 |
PURPOSE:To obtain an optical type recording carrier having improved smothness, hardness, hygroscopic deformability, etc. by providing a thin film consisting of an inorg. glass on a substrate which is transparent plastic, forming an information recording layer consisting of an amorphous alloy on the thin film and providing a surface protective layer consisting of inorg. glass on the recording layer. CONSTITUTION:A layer 2 consisting of alkali-free glass, for example, glass depositable by evaporation such as ''Code Number 7059'' produced by Corning Glass works is formed to 100-2,000Angstrom thickness on a transparent plastic substrate 1 such as polycarbonate, polymethyl methacrylate or the like, thus forming a layer having no pinholes, etc. A recording medium layer 3 of amorphous metal consisting of rare earth elements- transition elements is formed on the layer 2. A surface protective layer 4 consisting of inorg. glass is then formed on the layer 3. An outside surface protective layer 5 consisting of inorg. glass is provided on the surface of the substrate 1 opposite from the layer 2 if necessary. The exfoliation of the layer 2 arising from a large coefft. of thermal expansion and relatively large hygroscopic deformation of the substrate 1 and the oxidation deterioration owing to permeation of O2 are thus prevented and the photomagnetic information recording medium having improved smoothness, hardness and hygroscopicity and excellent durability is otd. |
