Patents by Inventor Yukihiro Koshika

Yukihiro Koshika 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).

  • Patent number: 6319325
    Abstract: It is to provide an apparatus for producing a thin film, a process for producing a thin film and a guide roller, in which an arc resistant property is provided, and the film formation can be stably conducted with preventing damage of the thin film thus formed. In an apparatus for producing a thin film, such as a plasma CVD apparatus, comprising a vacuum chamber, means for generating a plasma in the vacuum chamber, means for introducing a gas to the vacuum chamber, and a guide roller for running a material to be treated by winding and supporting in the vacuum chamber, an outer peripheral surface of the guide roller in contact and sliding with the material to be treated comprises an electric conductor on both end parts in a width direction of the guide roller, and an electric insulator on a central part thereof.
    Type: Grant
    Filed: February 16, 2000
    Date of Patent: November 20, 2001
    Assignee: Sony Corporation
    Inventors: Ryoichi Hiratsuka, Kikuji Kawakami, Yoshihito Ebine, Atsuhiro Abe, Yukihiro Koshika
  • Patent number: 5914180
    Abstract: A magnetic recording medium having a thin magnetic metal film formed by vapor deposition under an atmosphere of an introduced oxygen gas. The thickness of the surface oxide film having the degree of oxidation of 50% or higher is maintained so as to be not higher than 5% of the total film thickness of the thin magnetic metal film. The magnetic recording medium is affected to a lesser extent by the surface oxide layer such that it is superior in magnetic properties, such as coercivity, and in electromagnetic properties.
    Type: Grant
    Filed: September 21, 1995
    Date of Patent: June 22, 1999
    Assignee: Sony Corporation
    Inventors: Jota Ito, Takashi Chiba, Kenichi Sato, Hidetoshi Honda, Toshiharu Uchimi, Taketoshi Sato, Yukihiro Koshika, Yasumi Sato
  • Patent number: 5431833
    Abstract: A lubricant contains ester compound made of perfluoropolyether and long chain alkyl carboxylic acid or alcohol. The perfluoropolyether has hydroxyl or carboxyl group at its end. The ester compound is admixed with long chain alkyl amine of from 0.01 to 100 in mole ratio. The long chain alkyl may be partially fluorined or perfluoro alkyl. At least one of phosphoric ester, phosphorous ester and long chain carboxylate ester can be further admixed. A magnetic recording medium can be coated by the lubricant.
    Type: Grant
    Filed: November 5, 1993
    Date of Patent: July 11, 1995
    Assignee: Sony Corporation
    Inventors: Hirofumi Kondo, Toshiharu Uchimi, Yukihiro Koshika