Patents by Inventor Kazumitsu Kawakita

Kazumitsu Kawakita 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: 8822366
    Abstract: The present invention provides an olefin polymerization catalyst, which is free of polyfunctional aromatic compounds and has a large particle diameter, and a solid titanium component (I) which forms the catalyst.
    Type: Grant
    Filed: October 31, 2008
    Date of Patent: September 2, 2014
    Assignee: Mitsui Chemicals, Inc.
    Inventors: Kazuhisa Matsunaga, Kazutaka Tsuru, Kazumitsu Kawakita, Takashi Jinnai, Tetsunori Shinozaki
  • Patent number: 8742040
    Abstract: A solid titanium catalyst component (I) comprising titanium, magnesium, halogen, a specific cyclic ester compound (a) and a specific cyclic ester compound (b), an olefin polymerization catalyst containing this catalyst component (I), and an olefin polymerization process using this olefin polymerization catalyst are disclosed. According to the solid titanium catalyst component, the olefin polymerization catalyst and the process for preparing an olefin polymer of the invention, an olefin polymer having high stereoregularity and a wide molecular weight distribution can be prepared with high activity, preparation of an olefin polymer excellent not only in molding properties such as high-speed streatchability and high-speed moldability but also in rigidity becomes possible, and besides, production cost can be reduced.
    Type: Grant
    Filed: November 14, 2008
    Date of Patent: June 3, 2014
    Assignee: Mitsui Chemicals, Inc.
    Inventors: Kazuhisa Matsunaga, Kazutaka Tsuru, Kazumitsu Kawakita, Tetsunori Shinozaki
  • Publication number: 20100305285
    Abstract: A solid titanium catalyst component (I) comprising titanium, magnesium, halogen, a specific cyclic ester compound (a) and a specific cyclic ester compound (b), an olefin polymerization catalyst containing this catalyst component (I), and an olefin polymerization process using this olefin polymerization catalyst are disclosed. According to the solid titanium catalyst component, the olefin polymerization catalyst and the process for preparing an olefin polymer of the invention, an olefin polymer having high stereoregularity and a wide molecular weight distribution can be prepared with high activity, preparation of an olefin polymer excellent not only in molding properties such as high-speed streatchability and high-speed moldability but also in rigidity becomes possible, and besides, production cost can be reduced.
    Type: Application
    Filed: November 14, 2008
    Publication date: December 2, 2010
    Inventors: Kazuhisa Matsunaga, Kazutaka Tsuru, Kazumitsu Kawakita, Tetsunori Shinozaki
  • Publication number: 20100227991
    Abstract: The present invention provides an olefin polymerization catalyst, which is free of polyfunctional aromatic compounds and has a large particle diameter, and a solid titanium component (I) which forms the catalyst.
    Type: Application
    Filed: October 31, 2008
    Publication date: September 9, 2010
    Inventors: Kazuhisa Matsunaga, Kazutaka Tsuru, Kazumitsu Kawakita, Takashi Jinnai, Tetsunori Shinozaki
  • Patent number: 6630559
    Abstract: Disclosed are a propylene polymer having a high crystallinity of a boiled heptane-insoluble component contained therein, a high stereoregularity and an extremely long mesochain (continuous propylene units wherein directions of {acute over (&agr;)}-methyl carbons are the same as each other), and a process for preparing said polymer. Further disclosed is a propylene polymer composition comprising the above propylene polymer and at least one stabilizer selected from a phenol type stabilizer, an organophosphite type stabilizer, a thioether type stabilizer, a hindered amine type stabilizer a metallic salt of higher aliphatic acid. The propylene block polymer of the invention is well-balanced between rigidity, heat resistance and moisture resistance, and can be favorably used for sheet, filament, injection molded product, blow molded product, etc.
    Type: Grant
    Filed: July 6, 2001
    Date of Patent: October 7, 2003
    Assignee: Mitsui Chismicans, Inc.
    Inventors: Tetsunori Shinozaki, Kazumitsu Kawakita, Mamoru Kioka
  • Patent number: 6545099
    Abstract: Disclosed are a propylene polymer having a high crystallinity of a boiled heptane-insoluble component contained therein, a high stereoregularity and an extremely long mesochain (continuous propylene units wherein directions of &agr;-methyl carbons are the same as each other), and a process for preparing said polymer. Also disclosed are a propylene block copolymer containing a crystalline polypropylene portion having a high crystallinity of a boiled heptane-insoluble component contained therein, a high stereoregularity and an extremely long mesochain, and a process for preparing said copolymer. Further disclosed is a propylene polymer composition comprising the above propylene polymer or propylene block copolymer and at least one stabilizer selected from a phenol type stabilizer, an organophosphite type stabilizer, a thioether type stabilizer, a hindered amine type stabilizer and a metallic salt of higher aliphatic acid.
    Type: Grant
    Filed: July 6, 2001
    Date of Patent: April 8, 2003
    Assignee: Mitsui Chemicals Inc.
    Inventors: Tetsunori Shinozaki, Kazumitsu Kawakita, Mamoru Kioka
  • Publication number: 20020032296
    Abstract: Disclosed are a propylene polymer having a high crystallinity of a boiled heptane-insoluble component contained therein, a high stereoregularity and an extremely long mesochain (continuous propylene units wherein directions of &agr;-methyl carbons are the same as each other), and a process for preparing said polymer. Also disclosed are a propylene block copolymer containing a crystalline polypropylene portion having a high crystallinity of a boiled heptane-insoluble component contained therein, a high stereoregularity and an extremely long mesochain, and a process for preparing said copolymer. Further disclosed is a propylene polymer composition comprising the above propylene polymer or propylene block copolymer and at least one stabilizer selected from a phenol type stabilizer, an organophosphite type stabilizer, a thioether type stabilizer, a hindered amine type stabilizer and a metallic salt of higher aliphatic acid.
    Type: Application
    Filed: July 6, 2001
    Publication date: March 14, 2002
    Inventors: Tetsunori Shinozaki, Kazumitsu Kawakita, Mamoru Kioka
  • Publication number: 20020006993
    Abstract: Disclosed are a propylene polymer having a high crystallinity of a boiled heptane-insoluble component contained therein, a high stereoregularity and an extremely long mesochain (continuous propylene units wherein directions of &agr;-methyl carbons are the same as each other), and a process for preparing said polymer. Also disclosed are a propylene block copolymer containing a crystalline polypropylene portion having a high crystallinity of a boiled heptane-insoluble component contained therein, a high stereoregularity and an extremely long mesochain, and a process for preparing said copolymer. Further disclosed is a propylene polymer composition comprising the above propylene polymer or propylene block copolymer and at least one stabilizer selected from a phenol type stabilizer, an organophosphite type stabilizer, a thioether type stabilizer, a hindered amine type stabilizer and a metallic salt of higher aliphatic acid.
    Type: Application
    Filed: July 6, 2001
    Publication date: January 17, 2002
    Inventors: Tetsunori Shinozaki, Kazumitsu Kawakita, Mamoru Kioka
  • Patent number: 6323150
    Abstract: Disclosed is a process for preparing a solid titanium catalyst component, comprising the steps of (I) contacting a liquid magnesium compound with a liquid titanium compound to precipitate a solid in the contact liquid (&bgr;), and adding an electron donor (d-i) selected from the group consisting of a polycarboxylic ester and a polyether compound to the contact liquid (&bgr;) during the time from beginning to end of the solid precipitation, to form a solid product (&agr;); and (II) contacting the solid product (&agr;) obtained after completion of the solid precipitation with an electron donor (d-ii) selected from the group consisting of a polycarboxylic ester and a polyether compound, to prepare a solid titanium catalyst component. According to the process, a solid titanium catalyst component capable of polymerizing an olefin with high activity and capable of preparing an olefin polymer of high stereoregularity can be prepared.
    Type: Grant
    Filed: August 10, 1998
    Date of Patent: November 27, 2001
    Assignee: Mitsui Chemicals, Inc.
    Inventors: Shinichi Kojoh, Tsuneo Yashiki, Kazumitsu Kawakita, Masao Nakano, Sadahiko Matsuura
  • Patent number: 6284857
    Abstract: Disclosed are a propylene polymer having a high crystallinity of a boiled heptane-insoluble component contained therein, a high stereoregularity and an extremely long mesochain (continuous propylene units wherein directions of &agr;-methyl carbons are the same as each other), and a process for preparing said polymer. Further disclosed is a propylene polymer composition comprising the above propylene polymer and at least one stabilizer selected from a phenol type stabilizer, an organophosphite type stabilizer, a thioether type stabilizer, a hindered amine type stabilizer and a metallic salt of higher aliphatic acid. The propylene polymer of the invention is excellent in rigidity, heat resistance and moisture resistance, and can be favorably used for sheet, film, filament, injection molded product, blow molded product, etc.
    Type: Grant
    Filed: November 30, 1994
    Date of Patent: September 4, 2001
    Assignee: Mitsui Chemical, Inc.
    Inventors: Tetsunori Shinozaki, Kazumitsu Kawakita, Mamoru Kioka
  • Patent number: 6274678
    Abstract: Disclosed are a propylene block copolymer containing a crystalline polypropylene portion having a high crystallinity of a boiled heptane-insoluble component contained therein, a high stereoregularity and an extremely long mesochain, and a process for preparing said copolymer. Further disclosed is a propylene polymer composition comprising the above propylene block copolymer and at least one stabilizer selected from a phenol type stabilizer, an organophosphite type stabilizer, a thioether type stabilizer, a hindered amine type stabilizer and a metallic salt of higher aliphatic acid. The propylene block polymer of the invention is well-balanced between rigidity, heat resistance and moisture resistance, and can be favorably used for sheet, filament, injection molded product, blow molded product, etc.
    Type: Grant
    Filed: December 7, 1994
    Date of Patent: August 14, 2001
    Assignee: Mitsui Chemicals INC
    Inventors: Tetsunori Shinozaki, Kazumitsu Kawakita, Mamoru Kioka
  • Patent number: 5324805
    Abstract: The present invention relates to a novel ethylene/pentene-1 copolymer whose molded film has a good balance between impact resistance and tear properties and high transparency, also is prominently reduced in a variation of the transparency even after subjected to a heat treatment, and further shows high blocking resistance, provided that the copolymer fulfills specific requisites. The invention also relates to a process for the preparation of the above-mentioned ethylene/pentene-1 copolymer and a formulation of the ethylene/pentene-1 copolymer composition using a stabilizer. According to the invention, there can be obtained an ethylene/pentene-1 copolymer composition which is excellent in heat stability in the molding stage, long-term heat stability and weatherability.
    Type: Grant
    Filed: February 27, 1991
    Date of Patent: June 28, 1994
    Assignee: Mitsui Petrochemical Industries, Ltd.
    Inventors: Mamoru Kioka, Takashi Ueda, Masaya Yamada, Masaki Kohyama, Seiichi Ikeyama, Yoshinori Akana, Kenji Iwata, Hiroshi Nishikawa, Kazumitsu Kawakita, Hideki Sakai
  • Patent number: 5192731
    Abstract: In accordance with the present invention, there are provided carrier-supported titanium catalyst components containing magnesium, aluminum, halogen and titanium as essential ingredients, which are obtained by a reaction of[I] a magnesium containing support obtained by previously bringing a support into contact with an organometallic compound of a metal of the Group II to IIIA of the periodic table having at least one hydrocarbon group attached directly to the metal atom or with a halogen containing compound, followed by contact with a magnesium compound in the liquid state having no reducing ability,[II] a reducing organometallic compound, and[III] a titanium compound in the liquid state, and processes for preparing the same and, at the same time, catalysts containing the above-mentioned catalyst components for use in preparing ethylene polymer and processes for preparing ethylene polymer using the catalyst for use in preparing ethylene polymer.
    Type: Grant
    Filed: October 23, 1991
    Date of Patent: March 9, 1993
    Assignee: Mitsui Petrochemical Industries, Ltd.
    Inventors: Mamoru Kioka, Kazumitsu Kawakita, Akinori Toyota
  • Patent number: 5155078
    Abstract: In accordance with the present invention, there are provided carrier-supported titanium catalyst components containing magnesium, aluminum, halogen and titanium as essential ingredients, which are obtained by a reaction of[I] a magnesium containing support obtained by previously bringing a support into contact with an organometallic compound of a metal of the Group II to IIIA of the periodic table having at least one hydrocarbon group attached directly to the metal atom or with a halogen containing compound, followed by contact with a magnesium compound in the liquid state having no reducing ability,[II] a reducing organometallic compound, and[III] a titanium compound in the liquid state, and processes for preparing the same and, at the same time, catalysts containing the above-mentioned catalyst components for use in preparing ethylene polymer and processes for preparing ethylene polymer using the catalyst for use in preparing ethylene polymer.
    Type: Grant
    Filed: June 17, 1991
    Date of Patent: October 13, 1992
    Assignee: Mitsui Petrochemical Industries, Ltd.
    Inventors: Mamoru Kioka, Kazumitsu Kawakita, Akinori Toyota