Patents by Inventor Tsutomu Kempo

Tsutomu Kempo 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: 5134027
    Abstract: The improved magnetic recording medium having a magnetic layer on one side of a base support and a backcoat containing a binder and a carbon black on the other side is characterized in that the backcoat further contains an inorganic powder having a hardness of 3-6 on the Mohs scale, the carbon black having an average particle size of 20-100 m.mu., and the binder containing nitrocellulose having a viscosity of 1/8-1/3 second as measured by the falling-ball method.
    Type: Grant
    Filed: November 13, 1989
    Date of Patent: July 28, 1992
    Assignee: Konica Corporation
    Inventors: Takafumi Yanagita, Tsutomu Kempo
  • Magnetic recording medium containing a copolymer having an anionic functional group which forms an intermolecular salt
    Patent number: 5098785
    Abstract: A medium recording medium is provided which has a plurality of coated layers on a nonmagnetic base support, a least one of said coated layer containing a modified copolymer having introduced therein an anionic functional group which forms an intramolecular salt.
    Type: Grant
    Filed: November 21, 1989
    Date of Patent: March 24, 1992
    Assignee: Konica Corporation
    Inventors: Takafumi Yanagita, Tsutomu Kempo, Narito Goto, Takuo Nishikawa, Noboru Koyama, Yasushi Nakano, Setsuko Kawahara
  • Magnetic recording medium containing a polyurethane binder resin having a betaine group in the form of an intermolecular salt
    Patent number: 5064720
    Abstract: A magnetic recording medium containing a specific binder resin is disclosed. The magnetic recording medium comprising a magnetic layer which contains a magnetic powder and a binder, in which the binder comprises a polyurethane resin having an anionic functional group being in a form of intramolecular salt; and the magnetic powder is selected from the group consisting of a ferro-magnetic cobalt-containing iron oxide powder, a ferro-magnetic chromium dioxide powder anad a magnetic metal powder containing iron atoms and aluminum atoms in a portion of from 100:1 to 100:20 in terms of the number of atoms.
    Type: Grant
    Filed: August 22, 1989
    Date of Patent: November 12, 1991
    Assignee: Konica Corporation
    Inventors: Tsutomu Kempo, Atsuko Matsuda, Narito Goto