Patents by Inventor Yuichi Tokumoto

Yuichi Tokumoto 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: 7126037
    Abstract: Butene oligomer derivatives having tert-butyl groups as one of the terminal groups, having a repeating unit of the main hydrocarbon chain consisting of 80% by mole or more of —CH2C(CH3)2—, and carrying the other terminal group consisting of 60% by mole or more of 1,4-butanediol type functional groups. These derivatives are useful as macromonomers which can be subjected to polycondensation, polyaddition, etc.
    Type: Grant
    Filed: December 19, 2000
    Date of Patent: October 24, 2006
    Assignee: Nippon Petrochemicals Co., Lt.
    Inventors: Tsutomu Takashima, Koji Fujimura, Yuichi Tokumoto
  • Publication number: 20040034184
    Abstract: Butene oligomer derivatives having tert-butyl groups as one of the terminal groups, having a repeating unit of the main hydrocarbon chain consisting of 80% by mole or more of —CH2C(CH3)2—, and carrying the other terminal group consisting of 60% by mole or more of 1,4-butanediol type functional groups. These derivatives are useful as macromonomers which can be subjected to polycondensation, polyaddition, etc.
    Type: Application
    Filed: August 29, 2003
    Publication date: February 19, 2004
    Inventors: Tsutomu Takashima, Koji Fujimura, Yuichi Tokumoto
  • Patent number: 6476284
    Abstract: An efficient dehalogenation can be carried out by a method which comprises treating an organic compound containing a compound of halogen, such as fluorine or chlorine, as an impurity and having non-conjugated carbon-carbon double bonds, for example, butene polymer produced with a boron trifluoride catalyst, with an inorganic solid treating agent containing aluminum atoms. When the dehalogenation is conducted in the presence of a basic substance such as ammonia or an amine, it can be continued over long while inhibiting the isomerization of the non-conjugated carbon-carbon double bonds.
    Type: Grant
    Filed: October 19, 2000
    Date of Patent: November 5, 2002
    Assignee: Nippon Petrochemicals Company, Limited
    Inventors: Koichi Ohashi, Tsutomu Takashima, Teruhisa Kuroki, Koji Fujimura, Yuichi Tokumoto
  • Patent number: 6462151
    Abstract: Boron trifluoride can be recovered in a reusable state by a method that is economical and does not cause environmental pollution, which method comprises the steps of bringing a fluid containing boron trifluoride or its complex into contact with metal fluoride so as to selectively adsorb and remove boron trifluoride in the complex and heating the resultant metal tetrafluoroborate at a temperature in the range of 100 to 600° C. to separate it into boron trifluoride and metal fluoride. By applying the method to a process for producing polybutene or olefin oligomer using boron trifluoride complex catalyst, the catalyst can be recovered with retaining its activity and reused effectively.
    Type: Grant
    Filed: June 22, 2000
    Date of Patent: October 8, 2002
    Assignee: Nippon Petrochemicals Company, Limited
    Inventors: Tsutomu Takashima, Yuichi Tokumoto, Koji Fujimura
  • Patent number: 6300444
    Abstract: It is possible to produce butene polymer at high yield, which polymer contains 80 mol % or more of polymer molecules having terminal vinylidene structure and being low in the content of residual organic fluorine by a process comprising Step (I) to polymerize in liquid phase by adding complex catalyst composed of boron trifluoride, ether and alcohol and/or water in specified ratios to C4 fractions and Step (II) to reduce the content of trimer and lighter components contained in the obtained polymer to 0.2% by weight or less by distillation.
    Type: Grant
    Filed: April 15, 2000
    Date of Patent: October 9, 2001
    Assignee: Nippon Petrochemicals Company, Limited
    Inventors: Yuichi Tokumoto, Koichi Ohashi, Toshio Okada, Tsutomu Takashima
  • Patent number: 6084144
    Abstract: A boron trifluoride complex can be recovered without changing its molar coordination ratio, by applying a direct and/or alternating voltage to an electrically-nonconductive fluid in which at least a part of boron trifluoride complex is dispersed and/or dissolved, and separating the boron trifluoride complex by settling from the electrically-nonconductive fluid. By utilizing this method for the preparation of olefin oligomer using a boron trifluoride complex catalyst, it is possible to reuse the recovered catalyst as it stands for the reaction.
    Type: Grant
    Filed: October 15, 1998
    Date of Patent: July 4, 2000
    Assignee: Nippon Petrochemicals Company, Limited
    Inventors: Tsutomu Takashima, Yoshisuke Kakuyama, Shigeru Nishikida, Yuichi Tokumoto, Kouji Fujimura
  • Patent number: 5457228
    Abstract: A method for producing a lower alkyl acetate in which undesirable polymerization of the starting material of olefin and deterioration of catalyst can be avoided, a higher catalytic efficiency and a higher reaction rate are attained, the installation of reaction equipment is inexpensive and the operation of the reaction can be carried out without difficulty. The method of the invention comprises the steps of feeding acetic acid and an olefin both in a liquid state and in cocurrent through a continuous flow type fixed bed reactor containing an acidic ion exchange resin catalyst(s) under the conditions that the molar ratio of acetic acid to the olefin in a feed current is in the range of 1.0 to 2.0 and an LHSV of acetic acid relative to the catalyst layer is 0.1 to 10.0 with maintaining the inlet of the catalyst bed at 70.degree. C. to 120.degree. C.; cooling the obtained reaction mixture to a temperature not lower than 70.degree. C.; and recycling it to the catalyst bed.
    Type: Grant
    Filed: October 27, 1994
    Date of Patent: October 10, 1995
    Assignees: Daicel Chemical Industries, Ltd., Nippon Petrochemicals Company, Limited
    Inventors: Yuichi Tokumoto, Kazuo Sakamoto, Kikuo Sasaki, Isoo Shimizu
  • Patent number: 5436402
    Abstract: A method for preparing a high-purity p-isobutylstyrene is here disclosed which comprises the first step of reacting o- and/or m-isobutylethylbenzene, if necessary, together with isobutylbenzene, in the presence of an acid catalyst in a liquid phase at a reaction temperature of -10.degree. to 600.degree. C. so that the production of sec-butylethylbenzene in butylethylbenzene may not exceed 20% by weight, in order to form a mixture of p-isobutylethylbenzene and sec-butylethylbenzene; and the second step of bringing the mixture of p-isobutylethylbenzene and sec-butylethylbenzene recovered from the first step into contact with a dehydrogenation metal catalyst containing at least one metal selected from the groups Ib, IIb, VIa, VIIa and VIII of the periodic table at a reaction temperature of 300.degree. to 650.degree. C. under a reaction pressure of 50 kg/cm.sup.2 or less in a gaseous phase.
    Type: Grant
    Filed: October 17, 1994
    Date of Patent: July 25, 1995
    Assignee: Nippon Petrochemicals Co., Ltd.
    Inventors: Isoo Shimizu, Yasuo Matsumura, Yuichi Tokumoto, Kazumichi Uchida
  • Patent number: 5384426
    Abstract: Disclosed is an improved process for the refinement of isopropyl acetate, whereby there can be effectively prepared isopropyl acetate having a high purity of, for example, approximately 99.9%, in which a distillate fraction having a carbon number of 3 obtained by catalytically cracking petroleums such as naphtha or a crude propylene by-produced in a process for the preparation of isobutene by the dehydrogenation of isobutane.
    Type: Grant
    Filed: December 7, 1993
    Date of Patent: January 24, 1995
    Assignee: Daicel Chemical Industries, Ltd.
    Inventors: Kyuichi Ohyama, Giichi Shimada, Yuichi Tokumoto, Kazuo Sakamoto
  • Patent number: 5260477
    Abstract: A method for preparing .alpha.-(4-isobutylphenyl)propionic acid or its precursor is here disclosed which comprises a step (I) of dehydrogenating p-isobutylethylbenzene in a gaseous phase in the presence of a dehydrogenating metal catalyst to form p-isobutylstyrene and at least one unsaturated hydrocarbon compound selected from a group A defined in Claim 1; a step (II) of reacting p-isobutylstyrene obtained in the step (I) with carbon monoxide and hydrogen or with carbon monoxide and water or a lower alcohol in the presence of a transition metal complex carbonylating catalyst to form .alpha.-(4-isobutylphenyl)propionic acid or its precursor; and a step (III) of hydrogenating at least one unsaturated hydrocarbon compound selected from the group A obtained in the dehydrogenation step (I) to form p-isobutylethylbenzene, and recycling the thus formed p-isobutylethylbenzene through the step (I) as the raw material of the step (I).
    Type: Grant
    Filed: December 18, 1989
    Date of Patent: November 9, 1993
    Assignee: Nippon Petrochemicals Co., Ltd.
    Inventors: Isoo Shimizu, Yasuo Matsumura, Yuichi Tokumoto, Kazumichi Uchida