Patents by Inventor Masaaki Fukugauchi

Masaaki Fukugauchi 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 carrier
    Patent number: 6506531
    Abstract: A magnetic carrier exhibiting excellent durability against mechanical impact as exerted by vibration and capable of exhibiting a stable charging performance in electrophotography is provided.
    Type: Grant
    Filed: November 5, 1999
    Date of Patent: January 14, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshiyuki Hakata, Hiroomi Kakihara, Masaaki Fukugauchi, Kenji Okada, Yushi Mikuriya, Kazumi Yoshizaki
  • Magnetic carrier for electrophotography
    Patent number: 5654120
    Abstract: The disclosure describes a magnetic carrier for electrophotography having a number-average particle diameter of 1 to 1000 .mu.m, and comprising ferromagnetic iron compound particles, non-magnetic metal oxide particles and a phenol-based resin as a binder resin, the total amount of said ferromagnetic iron compound particles and said non-magnetic metal oxide particles being 80 to 99 wt %, and the ratio of the number-average particle diameter of said non-magnetic metal oxide particles and the number-average particle diameter of said ferromagnetic iron compound particles being more than 1.0.
    Type: Grant
    Filed: October 4, 1995
    Date of Patent: August 5, 1997
    Assignee: Toda Kogyo Corporation
    Inventors: Toshiyuki Hakata, Hiroomi Kakihara, Masaaki Fukugauchi
  • Superparamagnetic fine particles of iron oxide and magnetic recording media containing said particles
    Patent number: 5368933
    Abstract: Disclosed herein is superparamagnetic fine particles of iron oxide having an unsaturated fatty acid adsorbed on the surface of superparamagnetic fine particles and having a magnetization of not less than 50 emu/g, the rate of change of the magnetization of not more than 10%, and an Fe.sup.2+ content (calculated as Fe.sup.2+ /Fe.sup.3+ molar ratio) of 0.16-0.5.
    Type: Grant
    Filed: April 19, 1993
    Date of Patent: November 29, 1994
    Assignee: Toda Kogyo Corp.
    Inventors: Koso Aoki, Masaaki Fukugauchi, Tomoyuki Imai, Nanao Horiishi, Kazuyuki Hayashi
  • Superparamagnetic fine particles of iron oxide and magnetic recording media containing said particles
    Patent number: 5236783
    Abstract: Disclosed herein is superparamagnetic fine particles of iron oxide having an unsaturated fatty acid adsorbed on the surface of superparamagnetic fine particles, and having a magnetization of not less than 50 emu/g, the rate of change of the magnetization of not more than 10%, and an Fe.sup.2+ content (calculated as Fe.sup.2+ /Fe.sup.3+ molar ratio) of 0.16-0.5.
    Type: Grant
    Filed: February 20, 1991
    Date of Patent: August 17, 1993
    Assignee: Toda Kogyo Corp.
    Inventors: Koso Aoki, Masaaki Fukugauchi, Tomoyuki Imai, Nanao Horiishi, Kazuyuki Hayashi