Patents by Inventor Takahiro Kawana

Takahiro Kawana 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
    Patent number: 4696862
    Abstract: A magnetic recording medium includes a metal magnetic layer (4) formed on a nonmagnetic base (1). On one major surface (1A) of the nonmagnetic base (1) is formed a metal layer (2) at least the surface of which is oxidized, nitrogenated or carbonized on which the metal magnetic layer (4) is further formed. This magnetic recording medium is capable of improving the durability of the metal magnetic layer (4).
    Type: Grant
    Filed: January 12, 1983
    Date of Patent: September 29, 1987
    Assignee: Sony Corporation
    Inventors: Takahiro Kawana, Norio Yokoyama
  • Magnetic recording medium
    Patent number: 4401725
    Abstract: A magnetic recording medium consisting of a non-magnetic substrate and a thin film metal magnetic layer is disclosed. The magnetic recording medium carries polyphenyl ether compound having the following formula ##STR1## where n is an integer satisfying the following condition; 2.ltoreq.n.ltoreq.10.
    Type: Grant
    Filed: September 7, 1982
    Date of Patent: August 30, 1983
    Assignee: Sony Corporation
    Inventors: Kazunori Ozawa, Takahiro Kawana, Nakaharu Seki, Naoya Komada