Patents by Inventor Tadamichi Aoki

Tadamichi Aoki 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: 4967027
    Abstract: A method of inhibiting polymerization of styrenes is disclosed, comprising the process of jointly using nitrosophenols and p-tertiarybutyl catecol for composing the polymerization inhibiting agent usable during the distillation process of styrenes.
    Type: Grant
    Filed: June 20, 1989
    Date of Patent: October 30, 1990
    Assignees: Mitsubishi Petrochemical Co., Ltd., Huls Aktiengesellschaft
    Inventors: Hideyuki Takahashi, Shohei Suzuki, Tomohiko Takahama, Tadamichi Aoki, Yoshikazu Higaki, Karl Trukenbrod
  • Patent number: 4605742
    Abstract: A process for the production of piperidine by catalytic hydrogenation of furfurylamine and/or tetrahydrofurfurylamine in the presence of a hydrogenation catalyst by flowing hydrogen gas into a reaction zone, wherein the starting material is introduced into a liquid phase in the reaction zone, the liquid phase being maintained at a constant temperature, and the reaction product is withdrawn from the reaction zone in a gaseous form together with excess hydrogen gas.
    Type: Grant
    Filed: February 7, 1985
    Date of Patent: August 12, 1986
    Assignee: Mitsubishi Petrochemical Co., Ltd.
    Inventors: Shoichiro Mori, Tadamichi Aoki, Ryozo Hamana, Yutaka Nomura
  • Patent number: 4598159
    Abstract: A process for producing furfurylamine and/or tetrahydrofurfurylamine in a high yield is disclosed, which comprises subjecting a mixture of furfural and a primary amine to a liquid-phase catalytic hydrogenation using a hydrogenation catalyst in the presence of ammonia, wherein the primary amine is furfurylamine and/or tetrahydrofurfurylamine and the hydrogenation catalyst is selected from the group consisting of cobalt-based catalysts and nickel-based catalysts.
    Type: Grant
    Filed: December 27, 1984
    Date of Patent: July 1, 1986
    Assignee: Mitsubishi Petrochemical Co., Ltd.
    Inventors: Tadashi Ayusawa, Shoichiro Mori, Tadamichi Aoki, Ryozo Hamana
  • Patent number: 4568778
    Abstract: A process for producing tert-amylphenols is described, comprising reacting isoamylene with phenols in the presence of an inorganic solid acid catalyst or an acidic ion exchange resin catalyst. This process permits efficient production of tert-amylphenols, i.e., 2,4-di-tert-amylphenol and p-tert-amylphenol. These tert-amylphenols are useful as starting materials for preparation of color formers for color photography, additives for resins, oil-soluble dyes, additives for lubricating oils, etc.
    Type: Grant
    Filed: February 7, 1985
    Date of Patent: February 4, 1986
    Assignee: Mitsubishi Petrochemical Co., Ltd.
    Inventors: Makoto Imanari, Hiroshi Iwane, Takahiro Sugawara, Tadashi Ayusawa, Tadamichi Aoki
  • Patent number: 4544749
    Abstract: Catalytic hydrogenation of furfurylamine or tetrahydrofurfurylamine in the presence of a cobalt-based catalyst into piperidine can be industrially carried out in an organic solvent, wherein addition of ammonia is not needed. It has been believed heretofore that the presence of ammonia in the hydrogenation is essential in such catalytic hydrogenation.
    Type: Grant
    Filed: February 24, 1984
    Date of Patent: October 1, 1985
    Assignee: Mitsubishi Petrochemical Company Limited
    Inventors: Tadashi Ayusawa, Tadamichi Aoki, Ryozo Hamana
  • Patent number: 4479017
    Abstract: In a process for producing an ether compound by the catalytic hydrogenolysis of an acetal compound in the presence of a catalyst, the improvement wherein an acetal compound of the following formula (2) ##STR1## wherein R represents a hydrogen atom or a lower alkoxy group, Y represents an alkylene group having 2 to 12 carbon atoms, n represents a positive number of from 1 to 6, the two groups R(YO).sub.n may, together with the carbon atom to which they are bonded, represent a 1,3-dioxolane ring, and R.sup.1 and R.sup.2, independently from each other, represent a hydrogen atom or a C.sub.1 -C.sub.6 alkyl group, provided that at least one of R.sup.1 and R.sup.2 represents a hydrogen atom,is catalytically hydrogenolyzed in the presence of a palladium catalyst on a carbon carrier in the absence of an acid substance added, thereby to form an ether compound of the following formula (1)R(YO).sub.n CHR.sup.1 R.sup.2 (1)whereinR, R.sup.1, R.sup.2, Y and n are as defined.
    Type: Grant
    Filed: June 23, 1982
    Date of Patent: October 23, 1984
    Assignee: Mitsubishi Petrochemical Co., Ltd.
    Inventors: Tadashi Ayusawa, Tadamichi Aoki, Yutaka Nomura