Patents by Inventor Atsuhiko Hiai

Atsuhiko Hiai 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: 5258550
    Abstract: This invention relate to a process for producing glycine by reacting glycolonitrile, carbon dioxide and ammonia in the presence of water, comprising subjecting first water, glycolonitrile, carbon dioxide and ammonia to a pre-reaction at 80.degree.-120.degree. C. for 0.5-1 hour and then to the main reaction at 150.degree.-200.degree. C. and a process further comprising recycling the remaining mother liquor having separated the glycine from the reaction solution obtained by the above process to the system comprising water, glycolonitrile, carbon dioxide and ammonia to carry out the aforesaid pre-reaction and/or main reaction.
    Type: Grant
    Filed: July 8, 1991
    Date of Patent: November 2, 1993
    Assignee: Mitsui Toatsu Chemicals, Incorporated
    Inventors: Kenji Fujiwara, Nobutaka Ueda, Yuuji Matsuu, Hiroshi Kato, Atsuhiko Hiai
  • Patent number: 5254729
    Abstract: A method for purifying glycine characterized by comprising the steps of adjusting the pH of an aqueous glycine solution to 6 or less with a mineral acid and/or an organic acid or an acidic cation exchange resin and subsequently decoloring said aqueous glycine solution by active carbon treatment.
    Type: Grant
    Filed: May 24, 1991
    Date of Patent: October 19, 1993
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Kenji Fujiwara, Susumu Yoshinaga, Yuji Matsuu, Hiroshi Kato, Atsuhiko Hiai
  • Patent number: 5202479
    Abstract: A process for preparing glycine which comprises the steps of reacting glycolonitrile, carbon dioxide gas, ammonia and water to obtain a reaction solution containing glycine, concentrating this reaction solution in two steps, recycling a gaseous phase portion formed in a primary concentration step to a reaction zone, and recycling to the reaction zone, a mother liquor left after glycine crystals have been separated from a concentrate obtained in a secondary concentration step.
    Type: Grant
    Filed: February 1, 1991
    Date of Patent: April 13, 1993
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Kenji Fujiwara, Nobutaka Ueda, Yuji Matsuu, Hiroshi Kato, Atsuhiko Hiai
  • Patent number: 5110575
    Abstract: Sinterable crystalline aluminum nitride powder is produced by reacting alkyl aluminum with ammonia in a gas phase to produce an amorphous aluminum nitride presursor powder, and subjecting the precursor powder to a primary calcination in a reducing gas containing at least 20% (vol.) ammonia at 600.degree. C. to 1300.degree. C., and then subjecting the calcined aluminum nitride to a secondary calination in an inert gas or a reducing gas at 1400.degree.-1750.degree. C.
    Type: Grant
    Filed: May 31, 1991
    Date of Patent: May 5, 1992
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Kazuo Wakimura, Masao Tanaka, Atsuhiko Hiai
  • Patent number: 5019423
    Abstract: Supply equipment for providing a stable supply of feed gas of an organic metal compound at a constant concentration comprises a cylindrical vessel with an organic metal compound housed, an inlet tube of carrier gas for vaporizing said organic metal compound, an outlet tube for letting out the carrier gas substantially saturated with the vaporized organic metal compound, a room provided in the lower part of the vessel which is connected to said carrier gas inlet tube, a packed bed of an organic metal compound formed above said room, and a partition with a plurarity of pores partitioning said room and said packed bed.
    Type: Grant
    Filed: December 21, 1988
    Date of Patent: May 28, 1991
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Atsuhiko Hiai, Kazuo Wakimura
  • Patent number: 4983462
    Abstract: A method for preparing high-purity aluminum nitride having high thermal conductivity and heat resistance for aluminum nitride substrates, which comprises the steps of reacting an organic aluminum compound with an aminotriazine in a solvent to obtain an aluminum nitride precursor, separating the precursor form the solvent, and heating the precursor at a temperature of 600.degree. C. or more in a reducing atmosphere and/or a non-oxidizing atmosphere. An aluminum nitride sinter is prepared by, if necessary, adding a sintering auxiliary to the above aluminum nitride powder, molding the powder into a desired shape, and then sintering the molded material at a temperature of 1,600.degree. to 2,000.degree. C. in a non-oxidizing atmosphere.
    Type: Grant
    Filed: August 14, 1989
    Date of Patent: January 8, 1991
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Atsuhiko Hiai, Kazuo Wakimura, Masao Tanaka, Takao Tanaka
  • Patent number: 4869925
    Abstract: A method for preparing high-purity aluminum nitride having high thermal conductivity and heat resistance for aluminum nitride substrates, which comprises the steps of reacting an organic aluminum compound with an aminotriazine in a solvent to obtain an aluminum nitride precursor, separating the precursor from the solvent, and heating the precursor at a temperature of 600.degree. C. or more in a reducing atmosphere and/or a non-oxidizing atmosphere. An aluminum nitride sinter is prepared by, if necessary, adding a sintering auxiliary to the above aluminum nitride powder, molding the powder into a desired shape, and then sintering the molded material at a temperature of 1,600.degree. to 2,000.degree. C. in a non-oxidizing atmosphere.
    Type: Grant
    Filed: July 29, 1988
    Date of Patent: September 26, 1989
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Atsuhiko Hiai, Kazuo Wakimura, Masao Tanaka, Takao Tanaka
  • Patent number: 4094780
    Abstract: A process for the liquid phase oxidation of an organic substance-containing effluent which comprises subjecting said effluent to a liquid phase oxidation treatment in the presence of a copper catalyst at a copper ion concentration of 50-5000 ppm and also in presence of an ammonium ion concentration of five or more times the copper ion concentration thereby to oxidize the organic substances in the effluent, and recovering the copper catalyst from the treated effluent for reuse. The recovery of the copper catalyst may be effected either by a process in which the copper catalyst is separated as a precipitate or by a process using a resin adsorption.
    Type: Grant
    Filed: August 12, 1976
    Date of Patent: June 13, 1978
    Assignee: Mitsui Toatsu Chemicals Inc.
    Inventors: Yasuto Iwai, Masayoshi Okabe, Naotoshi Seki, Atsuhiko Hiai, Seiya Iguchi
  • Patent number: 3979392
    Abstract: Liquid drops such as molten urea contained in the waste gas from a melamine recovery process are separated from the waste gas by colliding the waste gas containing the liquid drops against a separator surface and providing said surface with a downwardly flowing film of a liquid such as molten urea.
    Type: Grant
    Filed: August 19, 1974
    Date of Patent: September 7, 1976
    Assignee: Mitsui Toatsu Chemicals, Incorporated
    Inventors: Tomoki Eguchi, Kenji Akitsune, Michio Unoki, Jinichi Kataoka, Toshiki Kato, Atsuhiko Hiai