Patents by Inventor Kimihisa Yamamoto

Kimihisa Yamamoto 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: 5250657
    Abstract: Polyarylene thioether is easily prepared by oxidative polymerizing an aromatic compound of the formula: ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are independently a hydrogen atom, a halogen atom, a lower alkyl group or a lower alkoxy group, and Y is a hydrogen atom or a group of the formula: ##STR2## wherein R.sup.5, R.sup.6, R.sup.7 and R.sup.8 are independently a hydrogen atom, a halogen atom, a lower alkyl group or a lower alkoxy group and X is --O--, --S--, a methylene group or an ethylene group with a sulfidizing agent in the presence of an acid and an oxidizing agent, or in the presence of an acid, a catalyst for oxidative polymerization and oxygen, or in the presence of a Friedel-Crafts catalyst.
    Type: Grant
    Filed: January 29, 1991
    Date of Patent: October 5, 1993
    Assignee: Seisan Kaihatsu Kagaku Kenkyusho
    Inventors: Eishun Tsuchida, Hiroyuki Nishide, Kimihisa Yamamoto, Mitsutoshi Jikei, Junya Katoh
  • Patent number: 5153305
    Abstract: A process for preparing a polyarylene thioether, comprising oxidation polymerizing at least one compound selected from the group consisting of diaryl disulfides represented by the formula (I): ##STR1## wherein, S is a sulfur atom, R.sup.1 to R.sup.8 are identical or different and each is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a halogen atom or an alkoxyl group having 1 to 10 carbon atoms, with at least one catalyst selected from the group consisting of vanadyl acetylacetonato, vanadyltetraphenyl porphyrin, vanadium acetylacetonato, vanadyl porphyrin, vanadium porphyrin, oxymolybdenum acetylacetonato and oxytungsten acetylacetonato, in the presence of an acid. Reaction conditions of the process are very mild, and the process is relatively simple and easy. In addition, the process is commercially advantageous in that very inexpensive reactants and catalysts can be used.
    Type: Grant
    Filed: July 11, 1990
    Date of Patent: October 6, 1992
    Assignees: Research Institute For Production Development, Idemitsu Petrochemical Co., Ltd.
    Inventors: Eishun Tsuchida, Hiroyuki Nishide, Kimihisa Yamamoto, Mitsutoshi Jikei
  • Patent number: 5135618
    Abstract: A process for manufacturing a solid state electrolytic capacitor having on an anode a dielectric coating layer and a solid state electrolytic layer, comprises the steps of forming a conductive polymer compound layer as the solid state electrolytic layer, and subsequently forming the dielectric coating layer by anodizing.
    Type: Grant
    Filed: September 3, 1991
    Date of Patent: August 4, 1992
    Assignee: NEC Corporation
    Inventors: Yoshihiko Saiki, Eishun Tsuchida, Kimihisa Yamamoto, Shinji Takeoka
  • Patent number: 4983720
    Abstract: A process for preparing polyarylene thioethers wherein thiophenols of formula ##STR1## are electrolytically polymerized in the presence of a Lewis acid and/or a proton acid.
    Type: Grant
    Filed: September 19, 1989
    Date of Patent: January 8, 1991
    Assignee: Idemitsu Petrochemical Co., Ltd.
    Inventors: Eishun Tsuchida, Hiroyuki Nishide, Kimihisa Yamamoto, Shu Yoshida
  • Patent number: 4931542
    Abstract: A process for preparing a substantially straight-chain polyarylene thioether by polymerizing a diphenyldisulfide of the formula ##STR1## in the presence of a lewis acid catalyst at temperatures of between -20.degree. C. and 50.degree. C.
    Type: Grant
    Filed: February 26, 1988
    Date of Patent: June 5, 1990
    Assignee: Idemitsu Petrochemical Company, Limited
    Inventors: Eishun Tsuchida, Hiroyuki Nishide, Kimihisa Yamamoto, Shu YHoshida