Patents by Inventor Michihisa Isobe

Michihisa Isobe 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).

  • Polymer electrolyte and process for producing the same
    Patent number: 6087031
    Abstract: A polymer electrolyte comprising a sulfonated polyethersulfone having an ion-exchange group equivalent weight of 870 to 5000 g/mol, which is obtainable by sulfonating a polyethersulfone having the structural unit represented by the following structural formula, ##STR1## The polymer electrolyte is cheap, easily mold-processable by virtue of soluble property in organic solvent and thermoplastic property, easily film-processable, highly water-resistant, and suitable for a fuel cell.
    Type: Grant
    Filed: December 23, 1997
    Date of Patent: July 11, 2000
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Katsuhiko Iwasaki, Taketsugu Yamamoto, Atsushi Terahara, Michihisa Isobe
  • Optical device
    Patent number: 5135791
    Abstract: An optical device comprising a mixture of a polymer constituted mainly of aromatic vinyl monomer units and polyphenylene ether, characterized in that the average molecular weight of the polyphenylene ether is from 0.3 to 0.7 expressed in terms of the intrinsic viscosity measured in chloroform at 25.degree. C.
    Type: Grant
    Filed: November 20, 1990
    Date of Patent: August 4, 1992
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Shozaburo Imai, Michihisa Isobe, Masahiko Moritani, Masahiro Niwano, Kenji Manabe
  • Optical disk substrate
    Patent number: 4812345
    Abstract: There is disclosed herein an optical disk substrate comprising a copolymer produced by polymerizing 50 to 65% by weight of methyl methacrylate (a) units, 20 to 35% by weight of tricyclo[5.2.1.0.sup.2.6 ]deca-8-yl methacrylate (b) units, 5 to 25% by weight of cyclohexyl methacrylate (c) units and 1 to 5% by weight of acrylic ester (d) units.
    Type: Grant
    Filed: February 11, 1988
    Date of Patent: March 14, 1989
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Shozaburo Imai, Michihisa Isobe, Kazuhiro Yokoo, Hideaki Matsuura
  • Optical resin material having improved birefringence
    Patent number: 4785053
    Abstract: An optical resin material comprising at least two constituent units each having positive and negative main polarizability differences of at least 50.times.10.sup.-25 cm.sup.3 in terms of absolute values has small birefringence and good water absorbance, heat resistance and moldability.
    Type: Grant
    Filed: July 2, 1986
    Date of Patent: November 15, 1988
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Iko Ito, Shozaburo Imai, Michihisa Isobe
  • Process for producing polyphenylene oxide
    Patent number: 4385168
    Abstract: A process for producing polyphenylene oxide which comprises contacting a phenolic monomer with oxygen in the presence of a catalyst composed of a manganese (II) salt and an ortho-hydroxyazo compound represented by the following formula: ##STR1## wherein A and B represent identical or different arylene ring having a valency of at least 2 and having an oxy group and an azo group directly linked to the ortho carbon atoms of the arylene ring and R represents hydrogen or lower alkyl group, or in the presence of said catalyst and an amine, in a polymerization solvent containing a base and thereby subjecting said phenolic monomer to an oxidative polymerization.
    Type: Grant
    Filed: March 1, 1982
    Date of Patent: May 24, 1983
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Katsuji Ueno, Takashi Maruyama, Haruo Inoue, Yoshiharu Tatsukami, Michihisa Isobe