Patents by Inventor Shuichi Uchimura

Shuichi Uchimura 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).

  • Copolymeric polycarbonate production method
    Patent number: 5484875
    Abstract: The present invention relates to a method for preparing copolymeric polycarbonates which comprises melt polycondensing a mixture of an aromatic dihydroxy compound containing an amount of 2-90 mol % of hydroquinone or substituted hydroquinones and a diester carbonate in the presence of a catalyst containing an alkali metal compound or an alkaline earth metal compound in an amount of 1.times.10.sup.-8 to 5.times.10.sup.-6 mole per mole of the total amount of the aromatic dihydroxy compound, then adding an acidic compound to the melt polycondensation product.
    Type: Grant
    Filed: May 19, 1995
    Date of Patent: January 16, 1996
    Assignee: GE Plastics Japan
    Inventors: Takeshi Sakashita, Tomoaki Shimoda, Kotaro Kishimura, Shuichi Uchimura
  • Copolymeric polycarbonate production method
    Patent number: 5418315
    Abstract: The method of this invention prepares copolymeric polycarbonates which have excellent mechanical properties, heat resistance and transparency, and which also have improved chemical resistance, hue, and residence stability by inducing the melt polycondensation of an aromatic dihydroxy compound containing an amount of 2-90 mol % of hydroquinone and/or substituted hydroquinones with a diester carbonate in the presence of a catalyst containing alkali metal compounds and/or alkaline earth metal compounds in an amount of 1.times.10.sup.-8 to 5.times.10.sup.-6 mole per mole of the total amount of the aromatic dihydroxy compound.
    Type: Grant
    Filed: March 14, 1994
    Date of Patent: May 23, 1995
    Assignee: GE Plastics Japan
    Inventors: Takeshi Sakashita, Tomoaki Shimoda, Kotaro Kishimura, Shuichi Uchimura
  • Melt catalytic preparation of copolymeric polycarbonate from hydroquinone
    Patent number: 5324809
    Abstract: The present invention relates to a method of preparing a copolymeric polycarbonate which comprises melt-polycondensing a mixture of an aromatic dihydroxy compound comprising hydroquinone or substituted hydroquinones and a diester carbonate in the presence of a catalyst containing alkali metal compounds and/or alkaline earth metal compounds.
    Type: Grant
    Filed: June 24, 1992
    Date of Patent: June 28, 1994
    Assignee: GE Plastics Japan, Ltd.
    Inventors: Takeshi Sakashita, Tomoaki Shimoda, Kotaro Kishimura, Shuichi Uchimura