Patents by Inventor Mikio Murai

Mikio Murai 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: 4645703
    Abstract: A magnetic recording medium comprises steep mountain-shaped protrusions having heights ranging 50-600 .ANG. and distributed at a rate of 1.times.50.sup.5 -1.times.10.sup.8 protrusions/mm.sup.2 on a surface of ferromagnetic metal layer and further thereon a lubricant layer; the magnetic recording medium is suitable for VTR tape which has a satisfactory durability for repeated use and eliminates head clogging and squealing.
    Type: Grant
    Filed: October 10, 1985
    Date of Patent: February 24, 1987
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Takashi Suzuki, Kunio Hibino, Mikio Murai, Shigeki Kawase, Koichi Shinohara, Norimoto Nouchi
  • Magnetic recording medium
    Patent number: 4540618
    Abstract: A magnetic recording media, e.g. VTR tape is improved by providing an undercoating layer on a polyester film substrate, the undercoating layer being formed under a ferromagnetic thin film and being an even-scattering of a large number of inorganic or organic granules distributed at a rate of 1000/mm.sup.2 or more.
    Type: Grant
    Filed: August 8, 1983
    Date of Patent: September 10, 1985
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Takashi Suzuki, Kunio Hibino, Mikio Murai, Shigeki Kawase, Koichi Shinohara
  • Magnetic recording medium
    Patent number: 4425404
    Abstract: In a magnetic recording medium having an oxygen-containing thin ferromagnetic metal layer formed on a nonmagnetic substrate, at least one compound capable of suppressing the hydration of the ferromagnetic metal ions by acting thereon is located on or in the vicinity of the surface of the thin ferromagnetic metal layer. A lubricant may further be applied on the thin ferromagnetic metal layer.
    Type: Grant
    Filed: September 17, 1982
    Date of Patent: January 10, 1984
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Takashi Suzuki, Kunio Hibino, Mikio Murai, Takashi Fujita