Patents by Inventor Tsugio Kumai

Tsugio Kumai 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: 7335408
    Abstract: A carbon nanotube composite material contains a carbon nanotube and a continuous layer of a metal covering the inner surface of the carbon nanotube. It is produced by forming a metallic matrix layer and treating the metallic matrix layer to form plural nanoholes in the metallic matrix layer to thereby form a nanohole structure, the nanoholes extending in a direction substantially perpendicular to the plane of the metallic matrix layer; forming carbon nanotubes inside the nanoholes; and covering inner surfaces of the carbon nanotubes with a continuous layer of a metal. It has a well controlled small size, has excellent and uniform physical properties, is resistant to oxidation of the metal with time, is highly chemically stable, has good durability enabling repetitive use, has good coatability, high wettability and dispersibility with other materials, is easily chemically modified, is easily handled and is useful in various fields.
    Type: Grant
    Filed: September 22, 2004
    Date of Patent: February 26, 2008
    Assignees: Fujitsu Limited, Tohoku University
    Inventors: Takashi Kyotani, Tomonori Ogawa, Kenichi Ito, Hideyuki Kikuchi, Hiroshi Nakao, Tsugio Kumai
  • Patent number: 7112377
    Abstract: A magnetic recording medium is disclosed that includes a substrate; an anodic alumina film formed on the substrate; a pore formed in the anodic alumina film; a carbon layer covering the surface of the anodic alumina film and the inner wall of the pore; a magnetic particle formed on the carbon layer inside the pore; and a lubrication layer covering the carbon layer and the magnetic particle.
    Type: Grant
    Filed: January 26, 2005
    Date of Patent: September 26, 2006
    Assignee: Fujitsu Limited
    Inventors: Ken-ichi Itoh, Tsugio Kumai, Shintaro Sato
  • Publication number: 20050255313
    Abstract: A carbon nanotube composite material contains a carbon nanotube and a continuous layer of a metal covering the inner surface of the carbon nanotube. It is produced by forming a metallic matrix layer and treating the metallic matrix layer to form plural nanoholes in the metallic matrix layer to thereby form a nanohole structure, the nanoholes extending in a direction substantially perpendicular to the plane of the metallic matrix layer; forming carbon nanotubes inside the nanoholes; and covering inner surfaces of the carbon nanotubes with a continous layer of a metal. It has a well controlled small size, has excellent and uniform physical properties, is resistant to oxidation of the metal with time, is highly chemically stable, has good durability enabling repetitive use, has good coatability, high wettability and dispersibility with other materials, is easily chemically modified, is easily handled and is useful in various fields.
    Type: Application
    Filed: September 22, 2004
    Publication date: November 17, 2005
    Applicants: FUJITSU LIMITED, TAKASHI KYOTANI
    Inventors: Takashi Kyotani, Tomonori Ogawa, Kenichi Ito, Hideyuki Kikuchi, Hiroshi Nakao, Tsugio Kumai
  • Publication number: 20050225900
    Abstract: A magnetic recording medium of the present invention includes a substrate and a porous layer on or above the substrate. The porous layer contains a plurality of pores each extending in a direction substantially perpendicular to a substrate plane and having a soft magnetic layer and a ferromagnetic layer inside in this order from the substrate side. The ferromagnetic layer has any one of (1) a thickness equal to or less than that of the soft magnetic layer, (2) a thickness one-thirds to three times a minimum bit length, the minimum bit length being determined by a linear recording density in recording, and (3) a thickness equal to or less than the total thickness of the soft magnetic layer and the soft magnetic underlayer.
    Type: Application
    Filed: June 7, 2005
    Publication date: October 13, 2005
    Applicant: FUJITSU LIMITED
    Inventors: Kenichi Itoh, Tsugio Kumai, Shintaro Sato, Koji Matsumoto
  • Publication number: 20050196644
    Abstract: A magnetic recording medium is disclosed that includes a substrate; an anodic alumina film formed on the substrate; a pore formed in the anodic alumina film; a carbon layer covering the surface of the anodic alumina film and the inner wall of the pore; a magnetic particle formed on the carbon layer inside the pore; and a lubrication layer covering the carbon layer and the magnetic particle.
    Type: Application
    Filed: January 26, 2005
    Publication date: September 8, 2005
    Applicant: FUJITSU LIMITED
    Inventors: Ken-ichi Itoh, Tsugio Kumai, Shintaro Sato
  • Patent number: 5671315
    Abstract: In an optical parts fixing device of the present invention, a substrate has an extension groove formed on an optical fiber fixing groove and has a width wider than that of the optical fiber fixing groove, or a substrate has the third groove which crosses end portions, opposed to each other, of the first groove for fitting an optical fiber therein and the second groove for fitting an optical device therein.
    Type: Grant
    Filed: March 9, 1995
    Date of Patent: September 23, 1997
    Assignee: Fujitsu Limited
    Inventors: Haruhiko Tabuchi, Tsugio Kumai, Seimi Sasaki, Kazunori Miura