Patents by Inventor Yasuhito Takahashi

Yasuhito Takahashi 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: 4992403
    Abstract: Catalysts for hydrotreating hydrocarbons are composed of a carrier substance consisting essentially of an oxide of aluminum and/or an oxide hydrate of aluminum, at least one compound selected from water-soluble compounds of metals of Group VI and Group VIII of the Periodic Table and at least one organic compound selected from mercapto-carboxylic acids of formula HS--(CH.sub.2).sub.n --COOR (where n is 1 to 3; R is H, alkali metal, alkaline earth metal or ammonium group or alkyl group with 1-10 carbons), thio-acids of formula R'--COSH (where R' is monovalent hydrocarbon with 1-15 carbons), amino-substituted mercaptans of formula H.sub.2 N--R"--SH (R" is divalent hydrocarbon with 1-15 carbons), dimercaptans of formula HS--R"--SH (R" is same as above) and mercapto-alcohols of formula (R.sup.a S--R"'--(OH).sub.n (where R"' is hydrocarbon with 1-15 carbons; R.sup.a is H or alkyl group with 1-2 carbons; and n is 1-2), and optionally phosphoric acid.
    Type: Grant
    Filed: August 16, 1989
    Date of Patent: February 12, 1991
    Assignee: Sumitomo Metal Mining Company Limited
    Inventors: Yasuhito Takahashi, Tomio Kawaguchi, Shigeru Sakai
  • Patent number: 4981828
    Abstract: A catalyst for the hydrotreatment of a hydrocarbon oil comprises a carrier of an inorganic oxide and an active component supported on the carrier and formed of at least one member selected from the group consisting of water-soluble compounds of molybdenum, tungsten, and the metal of Group 8 in the Periodic Table of Elements and at least one mercapto (--SH) group-containing organic compound selected from the group consisting a mercaptocarboxylic acids represented by the general formula:HS--(CH.sub.2).sub.n --COOR(wherein n stands for an integer in the range of 1 to 3 and R for a hydrogen atom, an alkali metal, an alkaline earth metal, ammonium, or a linear or branched naphthenic alkyl group having 1 to 10 carbon atoms), amino-substituted mercaptans represented by the general formula:H.sub.
    Type: Grant
    Filed: November 28, 1989
    Date of Patent: January 1, 1991
    Inventors: Yasuhito Takahashi, Shigeru Sakai
  • Patent number: 4845068
    Abstract: Supported catalysts for hydrotreating hydrocarbons comprise (a) at least one member selected from the group consisting of oxides of metals in Groups IV and VIII of the Periodic Table, and (b) at least one organic compound having a mercapto radical or radicals (--SH) selected from the group consisting of mercapto-carboxylic acids, including alkali metal, alkaline earth metal and ammonium salts thereof and esters thereof, bivalent mercaptans, amino-substituted mercaptans, and thiocarboxylic acids. These catalysts can be easily activated by treatment in the presence of hydrogen gas at a temperature in the range from room temperature to 400.degree. C. show higher activity than catalysts activated by conventional methods.
    Type: Grant
    Filed: April 22, 1988
    Date of Patent: July 4, 1989
    Assignee: Sumitomo Metal Mining Company Limited
    Inventors: Yasuhito Takahashi, Shigeru Sakai, Yoshimasa Inoue
  • Patent number: 4747110
    Abstract: A semiconductor laser device has a compound semiconductor substrate, a first semiconductor layer disposed on the compound semiconductor substrate, and a second semiconductor layer disposed on the first semiconductor layer. The second semiconductor layer has at least three thin film layers of at least two different semiconductor compounds, the film layers being laminated with the different semiconductor compound layers alternating. An electrically isolating region extends through the thickness of the second semiconductor layer and electrically divides the second semiconductor layer into first and second portions which differ in quantum level from each other. A third semiconductor layer is disposed on the second semiconductor layer, and first and second electrodes are disposed on the third semiconductor layer in positions for supplying current to the first and second portions, respectively, and a third electrode is disposed on the substrate at the surface thereof opposite to the first and second electrodes.
    Type: Grant
    Filed: February 13, 1986
    Date of Patent: May 24, 1988
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yasuhito Takahashi, Mototsugu Ogura, Nobuyasu Hase