Patents by Inventor Yasumi Sato

Yasumi 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).

  • Patent number: 7241471
    Abstract: A method of fabricating a low-noise, high-output and large-capacity magnetic recording medium compatible with the AIT3 format in which a metal magnetic film is formed by the vacuum evaporation process under supply of oxygen is disclosed. In the vacuum evaporation process, the running speed of a non-magnetic support is controlled within a range from 150 to 200 m/min, and on thus continuously fast-running, non-magnetic support, a Co magnetic thin film is formed under supply of oxygen so as to achieve a coercive force Hc of the Co magnetic thin film of 100 to 115 kA/m, and a squareness ratio of 0.79 or larger.
    Type: Grant
    Filed: July 6, 2004
    Date of Patent: July 10, 2007
    Assignee: Sony Corporation
    Inventors: Yasumi Sato, Jota Ito
  • Publication number: 20070141239
    Abstract: In order to attain a magnetic recording medium compliant with the AIT4 format and capable of accomplishing a block error rate of 1×10?4 or below, there is provided a magnetic recording medium having a magnetic layer composed of a metal magnetic thin film formed on a non-magnetic substrate composed of an aromatic polyamide film, in which the magnetic layer has a coercive force Hc of 120 kA/m to 235 kA/m, and a square ratio Rs of 0.69 or above.
    Type: Application
    Filed: January 30, 2007
    Publication date: June 21, 2007
    Inventor: Yasumi Sato
  • Patent number: 7217468
    Abstract: A method of fabricating a low-noise, high-output and large-capacity magnetic recording medium compatible with the AIT3 format in which a metal magnetic film is formed by the vacuum evaporation process under supply of oxygen is disclosed. In the vacuum evaporation process, the running speed of a non-magnetic support is controlled within a range from 150 to 200 m/min, and on thus continuously fast-running, non-magnetic support, a Co magnetic thin film is formed under supply of oxygen so as to achieve a coercive force Hc of the Co magnetic thin film of 100 to 115 kA/m, and a squareness ratio of 0.79 or larger.
    Type: Grant
    Filed: April 14, 2003
    Date of Patent: May 15, 2007
    Assignee: Sony Corporation
    Inventors: Yasumi Sato, Jota Ito
  • Publication number: 20050031906
    Abstract: In order to attain a magnetic recording medium compliant with the AIT4 format and capable of accomplishing a block error rate of 1×10?4 or below, there is provided a magnetic recording medium having a magnetic layer composed of a metal magnetic thin film formed on a non-magnetic substrate composed of an aromatic polyamide film, in which the magnetic layer has a coercive force Hc of 120 kA/m to 235 kA/m, and a square ratio Rs of 0.69 or above.
    Type: Application
    Filed: August 3, 2004
    Publication date: February 10, 2005
    Inventor: Yasumi Sato
  • Publication number: 20040240111
    Abstract: A method of fabricating a low-noise, high-output and large-capacity magnetic recording medium compatible with the AIT3 format in which a metal magnetic film is formed by the vacuum evaporation process under supply of oxygen is disclosed. In the vacuum evaporation process, the running speed of a non-magnetic support is controlled within a range from 150 to 200 m/min, and on thus continuously fast-running, non-magnetic support, a Co magnetic thin film is formed under supply of oxygen so as to achieve a coercive force Hc of the Co magnetic thin film of 100 to 115 kA/m, and a squareness ratio of 0.79 or larger.
    Type: Application
    Filed: July 6, 2004
    Publication date: December 2, 2004
    Inventors: Yasumi Sato, Jota Ito
  • Publication number: 20030215671
    Abstract: A method of fabricating a low-noise, high-output and large-capacity magnetic recording medium compatible with the AIT3 format in which a metal magnetic film is formed by the vacuum evaporation process under supply of oxygen is disclosed. In the vacuum evaporation process, the running speed of a non-magnetic support is controlled within a range from 150 to 200 m/min, and on thus continuously fast-running, non-magnetic support, a Co magnetic thin film is formed under supply of oxygen so as to achieve a coercive force Hc of the Co magnetic thin film of 100 to 115 kA/m, and a squareness ratio of 0.79 or larger.
    Type: Application
    Filed: April 14, 2003
    Publication date: November 20, 2003
    Inventors: Yasumi Sato, Jota Ito
  • 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: 5662984
    Abstract: A magnetic recording medium has a magnetic layer formed by a thin magnetic metal layer and a carbon protective layer on a non-magnetic substrate; the surface of the carbon protective layer has first protrusions formed by first particles and second protrusions formed by second particles; the carbon protective film has a thickness in the range of 3 nm to 30 nm, while the first protrusions have the heights of 65 nm.+-.15 nm to 95 nm.+-.15 nm and the second protrusions have the heights of 18 nm.+-.5 nm to 28 nm.+-.5 nm; since the surface properties of the carbon protective film are controlled, the electro-magnetic conversion characteristics may be prevented from being lowered due to the spacing losses for improving the running durability of the recording medium.
    Type: Grant
    Filed: May 27, 1994
    Date of Patent: September 2, 1997
    Assignee: Sony Corporation
    Inventors: Hidetoshi Honda, Yasumi Sato, Taketoshi Sato, Jota Ito, Yoshihito Ebine, Toshikazu Sasaki