Patents by Inventor Tetsuo Akazawa

Tetsuo Akazawa 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).

  • Battery separator and lithium secondary battery
    Patent number: 6627346
    Abstract: A battery separator favorably employable for lithium secondary battery comprises at least one porous film in which 100 to 40,000 ppm of particles of silicon dioxide, aluminum oxide, magnesium oxide, zinc oxide or metal oxides containing at least two metal elements selected from the group consisting of Si, Al, Mg and Zn having a mean diameter of 0.1 to 10 &mgr;m are dispersed in a porous resin matrix.
    Type: Grant
    Filed: November 10, 2000
    Date of Patent: September 30, 2003
    Assignee: Ube Industries, Ltd.
    Inventors: Masayuki Kinouchi, Tetsuo Akazawa, Takashi Oe, Ryuichiro Kogure, Kenji Kawabata, Yuuji Nakakita
  • Process for producing microporous film having breakage resistance when melted
    Patent number: 5258156
    Abstract: A process for producing a microporous stretched polyolefin film having a large number of micropores, whereby an unstretched polyolefin film is stretched to predetermined strain amount at a constant stretching temperature by using different strain rates in the initial stage to the final stage. A microporous polyolefin film obtained by the above process can retain a film state even at the melting point or higher temperatures when the film is fixed at the periphery.
    Type: Grant
    Filed: August 8, 1991
    Date of Patent: November 2, 1993
    Assignee: Ube Industries, Ltd.
    Inventors: Hiroshi Kurauchi, Tetsuo Akazawa