Patents by Inventor Kazumi Hirakawa

Kazumi Hirakawa 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).

  • Electric discharge recording materials
    Patent number: 4439485
    Abstract: A discharge recording material produced by successively forming a colored layer comprising mainly carbonblack and a binder, a deposited metal layer and optionally a protective layer on a support is provided. In particular, the discharge recording material wherein said carbonblack being carbonblack aggregates obtained by pretreating carbonblack particles with a plasticizer is provided.
    Type: Grant
    Filed: October 28, 1981
    Date of Patent: March 27, 1984
    Assignee: Honshu Seishi Kabushiki Kaisha
    Inventors: Shuji Takemura, Yoshihiko Kawano, Kazumi Hirakawa
  • Discharge recording medium
    Patent number: 4400706
    Abstract: A discharge recording medium having a colored insulating layer, a metal-vaporized layer and, as required, a protection layer formed in that order on a support member, wherein the colored insulating layer contains a graphite powder having particles of a specifically determined average size in an amount according to a specifically determined ratio with respect to a bonding resin in the colored insulating layer.
    Type: Grant
    Filed: July 28, 1981
    Date of Patent: August 23, 1983
    Assignee: Honshu Seishi Kabushiki Kaisha
    Inventors: Shuji Takemura, Kazumi Hirakawa, Tsuneto Yoshizumi