Patents by Inventor Kivoshi Sato

Kivoshi Sato has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Magnetic recording medium and method for manufacturing the same
    Patent number: 5766727
    Abstract: According to the present invention, a magnetic recording medium comprises a glass substrate, a first under layer, a second under layer, a magnetic layer, a protective layer and a lubricant layer in the named order. The first under layer is formed on a glass plate, a surface of which is highly polished. The second under layer is formed, on the first under layer, of a material differing from a material of the first under layer, and has a thickness greater than a thickness of the first under layer. The magnetic layer is formed on the second under layer. The protective layer is formed on the magnetic layer, on whose surface a texture due to dispersed hard minute particles appears. The lubricant layer is formed on the protective layer.
    Type: Grant
    Filed: April 26, 1996
    Date of Patent: June 16, 1998
    Assignee: Hoya Corporation
    Inventors: Keiji Moroishi, Kivoshi Sato, Isao Kawasumi, Hisao Kawai