Patents by Inventor Yasumichi Shigehisa

Yasumichi Shigehisa 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).

  • Publication number: 20010004650
    Abstract: A silicon rubber composition for insert molding or two-cavity molding comprising from 0.01 wt % to 10 wt % of a phenolic compound having at least one alkoxy group and at least one alkenyl group per molecule.
    Type: Application
    Filed: December 15, 2000
    Publication date: June 21, 2001
    Inventors: Yuichi Tsuji, Yasumichi Shigehisa, Takayoshi Otomo
  • Patent number: 6043309
    Abstract: A curable liquid silicone rubber composition for use in high-voltage electrical insulating parts, which consists of (A) a polyorganosiloxane containing alkenyl groups, (B) fumed silica, (C) a polyorganohydriodosiloxane, (D) a platinum catalyst, (E) finely powdered aluminum hydroxide, and (F) 1 to 150 parts by weight of a finely powdered metal compound selected from the group consisting of finely powdered carbonate or finely powdered hydrogen salt of a metal selected from the 1st, 2nd, 3rd, 7th, or 9th group of the periodic table.
    Type: Grant
    Filed: January 28, 1998
    Date of Patent: March 28, 2000
    Assignee: Dow Corning Toray Silicone Co., Ltd.
    Inventors: Akito Nakamura, Yasumichi Shigehisa, Yuichi Tsuji
  • Patent number: 5994461
    Abstract: A high voltage electrical insulator formed from a curable liquid silicone rubber composition, and subsequently cured, a composition consisting essentially of(A) 100 weight parts of a fluid mixture of polyorganosiloxane comprising(a) at least 5 weight percent of a polyorganosiloxane resin comprising repeating units selected from the group consisting of SiO.sub.4/2 and RSiO.sub.3/2, where R is a monovalent hydrocarbon group, and(b) polydiorganosiloxane having a viscosity in the range from about 100 mPa.multidot.s to 100,000 mPa.multidot.s, that contains at least 2 silicon-bonded alkenyl groups in each molecule,(B) 1 to 100 weight parts microparticulate silica,(C) polyorganohydrogensiloxane that contains at least 2 silicon-bonded hydrogen atoms in each molecule, in a quantity that provides a value from 0.
    Type: Grant
    Filed: June 25, 1998
    Date of Patent: November 30, 1999
    Assignee: Dow Corning Toray Silicone Co., Ltd.
    Inventors: Akito Nakamura, Yasumichi Shigehisa, Yuichi Tsuji
  • Patent number: 5973030
    Abstract: Liquid silicone rubber compositions that prior to cure have good fluidity and excellent moldability and that cure into a highly flame retardant silicone rubber with excellent high-voltage electrical insulating properties. The liquid silicone rubber compositions comprise: (A) polyorganosiloxane; (B) fumed silica; (C) surface-treated zinc carbonate powder as afforded by treating the surface of (a) zinc carbonate powder or basic zinc carbonate powder with (b) an organosilicon compound selected from organosilanes, organosilazanes, and organosiloxane oligomers; (D) polyorganohydrogensiloxane; and (E) platinum catalyst. The liquid silicone rubber compositions may further comprise (F) surface treated aluminum hydroxide powder, (G) triazole compound, and (H) a reaction mixture of (d) platinum compound and (e) 3,5-dimethyl-1-hexyn-3-ol.
    Type: Grant
    Filed: May 22, 1997
    Date of Patent: October 26, 1999
    Assignee: Dow Corning Toray Silicon Co., Ltd.
    Inventors: Takao Matsushita, Yasumichi Shigehisa, Yuichi Tsuji
  • Patent number: 5942571
    Abstract: A liquid silicone rubber composition for use in high-voltage eletrical insulating parts comprising (A) a polyorganosiloxane containing alkenyl groups, (B) fumed silica, (C) a polyorganohydridosiloxane, (D) a platinum type catalyst, (E) finely powdered aluminum hydroxide, and (F) a powdered metal compound selected from the group consisting of powdered zinc oxidc, powdered zinc borate, and powdered magnesium hydroxide and a method for manufacturing such a composition.
    Type: Grant
    Filed: January 28, 1998
    Date of Patent: August 24, 1999
    Assignee: Dow Corning Toray Silicone Co., Ltd.
    Inventors: Akito Nakamura, Yasumichi Shigehisa, Yuichi Tsuji
  • Patent number: 5904887
    Abstract: A manufacturing method for making a composite comprising silicone rubber and a thermoplastic resin in high precision and in high productivity. In the method, a thermoplastic resin is injected into the cavity of a mold. Then, a liquid silicone rubber composition which comprises (A) organopolysiloxane, (B) spherical fine particle catalyst consisting of platinum base catalyst-containing thermoplastic resin, (C) organohydrogenpolysiloxane, and (D) hydrosilylation reaction inhibiting compound, is injected into the same mold and cured.
    Type: Grant
    Filed: September 20, 1995
    Date of Patent: May 18, 1999
    Assignee: Dow Corning Toray Silicone Co., Ltd.
    Inventors: Akito Nakamura, Yasumichi Shigehisa
  • Patent number: 5880199
    Abstract: A liquid silicone rubber composition that prior to its cure has a suitable fluidity and excellent moldability and that cures into a highly flame retardant silicone rubber molding with excellent electrical properties. The liquid silicone rubber composition comprises(A) polyorganosiloxane,(B) microparticulate silica,(C) aluminum hydroxide powder,(D) zinc carbonate powder,(E) polyorganohydrogensiloxane,(F) benzotriazole,(G) the reaction mixture of(a) a platinum compound and(b) 3,5-dimethyl-1-hexyn-3-ol, and(H) hydrosilylation reaction catalyst.
    Type: Grant
    Filed: May 22, 1997
    Date of Patent: March 9, 1999
    Assignee: Dow Corning Toray Silicone Co., Ltd.
    Inventors: Takao Matsushita, Yasumichi Shigehisa, Yuichi Tsuji
  • Patent number: 5399602
    Abstract: The composition of the present invention comprises an oil-resistant silicone rubber composition that undergoes little swelling even when used in regular or continuous contact with mineral oil-based lubricating oil such as engine oil and so forth. The oil-resistant silicone rubber composition comprises:(A) a dimethylsiloxane-3,3,3-trifluoropropylmethylsiloxane-methylvinylsiloxane copolymer gum that contains 0.001 to 5 mole percent methylvinylsiloxane unit,(B) a hydrocarbon oil or diorganopolysiloxane oil wherein the total in each diorganopolysiloxane oil molecule of the number of silicon-bonded hydrogen atoms and the number of functional groups reactive with component (A) or (C) is less than two,(C) a reinforcing filler, and(D) a curing agent in a quantity sufficient to cure the composition.
    Type: Grant
    Filed: August 1, 1994
    Date of Patent: March 21, 1995
    Assignee: Dow Corning Toray Silicone, Co. Ltd.
    Inventors: Takao Matsushita, Yasumichi Shigehisa
  • Patent number: 5378742
    Abstract: The composition of the present invention comprises a oil-resistant silicone rubber composition that undergoes little swelling even when used in regular or continuous contact with mineral oil-based lubricating oil such as engine oil and so forth. The oil-resistant silicone rubber composition comprises:(A) a dimethylsiloxane-3,3,3-trifluoropropylmethylsiloxane-methylvinylsiloxane copolymer gum that contains 0.001 to 5 mole percent methylvinylsiloxane unit,(B) a hydrocarbon oil or diorganopolysiloxane oil wherein the total in each diorganopolysiloxane oil molecule of the number of silicon-bonded hydrogen atoms and the number of functional groups reactive with component (A) or (C) is less than two,(C) a reinforcing filler, and(D) a curing agent in a quantity sufficient to cure the composition.
    Type: Grant
    Filed: September 28, 1993
    Date of Patent: January 3, 1995
    Assignee: Dow Corning Toray Silicone Co., Ltd.
    Inventors: Takao Matsushita, Yasumichi Shigehisa