| 摘要 |
PURPOSE:To obtain a photomagnetic recording medium having improved durability by coating, directly or via other layer, at least one face of a magnetic recording layer consisting of a vertically magnetized film with a protective film essentially consisting of a compound oxide composed of a specific ratio of a group III metallic oxide and group IV metallic oxide. CONSTITUTION:At least one face of the magnetic recording layer consisting of the vertically magnetized film is coated directly or via the other layer with the protective film essentially consisting of the compound oxide composed of 20-85mol% group III metallic oxide and 80-15mol% group IV metallic oxide. for example, Al2O3, In2O3, Y2O3, La2O3, etc. are used as the group III metallic oxide to constitute the protective film and, for example, SiO2, TiO2, ZrO2, HfO2, SnO2, etc. are used for the group IV metallic oxide. Both oxides constitute the protective film preferably in the mixed state at a molecular level. The protective film is not always limited to the case in which said film is constituted of only the above-mentioned two kinds of the oxides and for example, a small amt. of a group IIa metallic oxide, for example, MgO, CaO and BaO may be incorporated therein. The film thickness of the protective film is generally enough with 100-10000Angstrom .
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