Patents by Inventor Keisuke OOYAMA

Keisuke OOYAMA 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: 10964986
    Abstract: An object of the invention is to provide a separator for an electrochemical element in which the occurrence of fluff on the sheet surface thereof is suppressed and an internal short-circuit defect rate is low, and the invention provides a separator for an electrochemical element, comprising: a fibrillated solvent spun cellulose fiber; and a synthetic fiber, wherein the separator for an electrochemical element contains, as the synthetic fiber, from 5 to 40% by weight of a core-sheath type composite fiber having a fiber diameter of 6.0 ?m or less which is composed of: a core component made of a resin having a melting point of 160° C. or more; and a sheath component made of polyethylene.
    Type: Grant
    Filed: October 17, 2017
    Date of Patent: March 30, 2021
    Assignee: MITSUBISHI PAPER MILLS LIMITED
    Inventors: Keisuke Ooyama, Takao Masuda
  • Patent number: 10818898
    Abstract: A separator for electrochemical elements includes beaten solvent-spun cellulose fibers and rayon fibers having a fiber diameter of 9.5 ?m or less. More preferably, the separator for electrochemical elements has a content of the rayon fibers relative to all fibers of 10 to 25% by mass, and can be applied to electrochemical elements such as electric double layer capacitors, hybrid capacitors, redox capacitors, and lithium secondary batteries. The separator can provide low internal short circuit failure rates and high surface strength.
    Type: Grant
    Filed: May 1, 2017
    Date of Patent: October 27, 2020
    Assignee: MITSUBISHI PAPER MILLS LIMITED
    Inventors: Toshihiro Shigematsu, Masatoshi Kito, Keisuke Ooyama
  • Publication number: 20190252661
    Abstract: An object of the invention is to provide a separator for an electrochemical element in which the occurrence of fluff on the sheet surface thereof is suppressed and an internal short-circuit defect rate is low, and the invention provides a separator for an electrochemical element, comprising: a fibrillated solvent spun cellulose fiber; and a synthetic fiber, wherein the separator for an electrochemical element contains, as the synthetic fiber, from 5 to 40% by weight of a core-sheath type composite fiber having a fiber diameter of 6.0 ?m or less which is composed of: a core component made of a resin having a melting point of 160° C. or more; and a sheath component made of polyethylene.
    Type: Application
    Filed: October 17, 2017
    Publication date: August 15, 2019
    Applicant: MITSUBISHI PAPER MILLS LIMITED
    Inventors: Keisuke OOYAMA, Takao MASUDA
  • Publication number: 20190148697
    Abstract: A separator for electrochemical elements includes beaten solvent-spun cellulose fibers and rayon fibers having a fiber diameter of 9.5 ?m or less. More preferably, the separator for electrochemical elements has a content of the rayon fibers relative to all fibers of 10 to 25% by mass, and can be applied to electrochemical elements such as electric double layer capacitors, hybrid capacitors, redox capacitors, and lithium secondary batteries. The separator can provide low internal short circuit failure rates and high surface strength.
    Type: Application
    Filed: May 1, 2017
    Publication date: May 16, 2019
    Applicant: Mitsubishi Paper Mills Limited
    Inventors: Toshihiro SHIGEMATSU, Masatoshi KITO, Keisuke OOYAMA