Magneto-optical disk and its manufacture

Abstract

Abstract PURPOSE:To obtain satisfactory recording and reproducing characteristics by preliminarily coating at least one face of a transparent substrate with an SiO2 film and forming a protective film of a base. CONSTITUTION:At least one face 11 of a transparent substrate 10 is coated with an SiO2 film, and it is preferable that the film thickness is in the range of 2,000-2,000Angstrom , and 1,300-1,500Angstrom film thickness is most preferable. The base protective layer 12, a magneto-optical recording film 13, and a protective layer 14 are formed and laminated on both recording faces of the substrate 10 by sputtering. The film 13 is sandwiched between layers 12 and 14 on both sides. A protective resin layer 15 consisting of an ultraviolet-curing resin or the like is formed on the layer 14. The layer 15 may consist of a transparent acryl, an epoxy resin, a polycarbonate, or the like. Layers 12 and 14 consist of an oxide or nitride like a Y2O3 or an SiN. A material having 1.8-2.2 refractive index is selected as the material of the layer 12 and its film thickness is about 900Angstrom , and the layer 14 protects the surface of the film 13 and has 800-900Angstrom film thickness. Thus, satisfactory recording and reproducing characteristics are obtained and the mass productivity of a magneto-optical disk is improved.

Inventors

• 👤 Shinichi Katsuta
• 👤 伸一 勝田
• 👤 Akira Ito
• 👤 亮 伊藤
• 👤 Takayuki Matsumoto
• 👤 隆幸 松本

Bibliographic Details