Patents by Inventor Tamotsu Hatakoshi

Tamotsu Hatakoshi 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: 5576111
    Abstract: A surface of a non-magnetic base plate is first coarsened to a required surface roughness and an ultrasonic vibration is then applied to the surface of the non-magnetic base plate while the nonmagnetic base plate is immersed in a liquid. Thereafter, a magnetic recording layer and a protective layer are successively formed on the surface of the non-magnetic base plate thereby to produce a magnetic recording medium. It is preferable that the frequency of a ultrasonic is within a range from 200 kHz to 1600 kHz. Surface fractional properties of the magnetic recording medium can adequately be controlled without variation of floatation height of a magnetic head during its running by varying an ultrasonic oscillation output and an ultrasonic processing time.
    Type: Grant
    Filed: July 22, 1994
    Date of Patent: November 19, 1996
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Katsumi Onodera, Koji Ito, Manabu Koike, Tamotsu Hatakoshi, Kazuyoshi Tomita, Kazuo Nimura
  • Method for fabricating magnetic recording medium
    Patent number: 5232750
    Abstract: A surface of a non-magnetic base plate is first coarsened to a required surface roughness and an ultrasonic vibration is then applied to the surface of the non-magnetic base plate while the non-magnetic base plate is immersed in a liquid. Thereafter, a magnetic recording layer and a protective layer are successively formed on the surface of the non-magnetic base plate thereby to produce a magnetic recording medium. It is preferable that the frequency of a ultrasonic vibration is within a range from 200 kHz to 1600 kHz. Surface fractional properties of the magnetic recording medium can adequately be controlled without variation of the floatation height of a magnetic head during its running by varying an ultrasonic oscillation output and an ultrasonic processing time.
    Type: Grant
    Filed: September 16, 1991
    Date of Patent: August 3, 1993
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Katsumi Onodera, Koji Ito, Manabu Koike, Tamotsu Hatakoshi, Kazuyoshi Tomita, Kazuo Nimura