Patents by Inventor Yoshihisa Tomotaki

Yoshihisa Tomotaki 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: 6433042
    Abstract: A curing agent for epoxy resin which comprises at least one selected from the compound of the formula (1) and its salt, as an effective component wherein X is —(CH2)n- or —(CH2)1-Y—(CH2)m- , Y is —N(R1)—, —O— or —S—, R1 is alkyl having 1 to 8 carbon atoms or amino. n is a number of 2, 3, 5 to 11, 1 and m are each a number of 1 to 8.
    Type: Grant
    Filed: February 5, 2001
    Date of Patent: August 13, 2002
    Assignee: Otsuka Kagaku Kabushiki Kaisha
    Inventors: Yoshihisa Tomotaki, Takashi Kitajima, Keiichiro Ishikawa, Akihiro Nabeshima, Tomohiro Furuichi
  • Patent number: 6380288
    Abstract: A rubber composition prepared by compounding 0.05 to 20 parts by weight of at least one selected from substituted hydrazide compounds represented by the following Formulas (I) to (IV) per 100 parts by weight of a rubber component comprising at least one rubber selected from the group consisting of natural rubber and synthetic rubber, and a pneumatic tire using the same: wherein A represents one selected from the group consisting of an aromatic group which may have a substituent, a hydantoin ring which may have a substituent, and a saturated or unsaturated linear hydrocarbon having 1 to 18 carbon atoms; Y represents hydrogen, an amino group, an alkyl group having 1 to 18 carbon atoms, a cycloalkyl group, an alkenyl group, an aromatic group, a pyridyl group or hydrazino group; and R1 to R11 each represent hydrogen, an alkyl group having 1 to 18 carbon atoms, a cycloalkyl group or an aromatic group.
    Type: Grant
    Filed: July 17, 2000
    Date of Patent: April 30, 2002
    Assignees: Bridgestone Corporation, Otsuka Chemical Co., Ltd.
    Inventors: Masahiro Hojo, Tomohiro Kusano, Akihiko Matsue, Kenichi Sugimoto, Shigeki Kamo, Yoshihisa Tomotaki, Akinori Oka, Ken Hirayama
  • Patent number: 6372825
    Abstract: The present invention provides an aqueous solution of an epoxy resin and a solid thereof, which is obtained by the following manner that an epoxy compound or a solution of the epoxy compound in organic solvent, and an amine compound of the formula (1), an aqueous solution thereof, a solution of the amine compound in organic solvent, or a solution thereof in a mixture of water and organic solvent, are mixed together so that the epoxy compound and the amine compound are reacted or polymerized to obtain a solution of an epoxy resin, to which water is added and heated to remove the organic solvent and unreacted amine compound, and a process for preparing the same NH2N(R1)(R2)  (1) wherein R1 and R2 are the same or different and each is alkyl having 1 to 6 carbon atoms, alkylene having 2 to 11 carbon atoms or a group represented by —R3—N(R4)—R5— which are formed when both are bonded, R3 and R5 are the same or different and each is alkylene having 1 to 6 carbon atoms, and R4 is a
    Type: Grant
    Filed: May 9, 2000
    Date of Patent: April 16, 2002
    Assignee: Otsuka Kagaku Kabushiki Kaisha
    Inventors: Yoshihisa Tomotaki, Takashi Kitajima, Keiichiro Ishikawa, Akihiro Nabeshima, Tomohiro Furuichi
  • Patent number: 6359036
    Abstract: A curing agent for epoxy resin which comprises at least one selected from 1-aminopyrrolidine and its salt.
    Type: Grant
    Filed: December 1, 1999
    Date of Patent: March 19, 2002
    Assignee: Otsuka Kagaku Kabushiki Kaisha
    Inventors: Yoshihisa Tomotaki, Takashi Kitajima, Keiichiro Ishikawa, Akihiro Nabeshima, Tomohiro Furuichi
  • Patent number: 5981764
    Abstract: 1-Aminopyrrolidine which is obtained by reacting hydrazine hydrate with a compound represented by the following formula (I):X.sup.1 --C.sub.4 H.sub.8 --X.sup.2 (I)wherein X.sup.1 and X.sup.2 are the same or different, and each represents a leaving group, in methanol; and a process for producing 1-aminopyrrolidine, comprising the step of reacting hydrazine hydrate with the above compound represented by formula (I) in methanol.
    Type: Grant
    Filed: July 24, 1998
    Date of Patent: November 9, 1999
    Assignee: Otsuka Chemical Co., Ltd.
    Inventors: Tsukasa Maekawa, Yoshihisa Tomotaki, Keiichiro Ishikawa, Akihiro Nabeshima, Tomohiro Furuichi
  • Patent number: 4886891
    Abstract: The present invention provides a process for preparing a 1,1-disubstituted ethylene derivative of the formula ##STR1## which comprises reacting lead with a carbinol derivative of the formula ##STR2## wherein R.sup.1, R.sup.2, R.sup.3, X, Y, m and n are defined in the specification. The reaction is conducted more advantageously in the presence of a metal having higher ionization tendency than lead.
    Type: Grant
    Filed: December 18, 1987
    Date of Patent: December 12, 1989
    Assignee: Otsuka Kagaku Kabushiki Kaisha
    Inventors: Shigeru Torii, Masatoshi Taniguchi, Michio Sasaoka, Yoshihisa Tomotaki, Mitsuo Akada, Hideo Tanaka, Akira Suzuki, Shiro Yamashita