Patents by Inventor Yoshihiro Sobajima

Yoshihiro Sobajima 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: 6660797
    Abstract: This invention provides a propylene-based composition for the molded polypropylene resin articles excellent in resistance to scratching and moldability, and well-balanced properties between high rigidity and high impact strength, and also provides a method for molding the above propylene-based composition, thereby providing high-performance industrial parts and automobile parts, in particular automobile interior parts.
    Type: Grant
    Filed: October 10, 2001
    Date of Patent: December 9, 2003
    Assignee: Japan Polychem Corporation
    Inventors: Yoshihiro Banno, Yoshihiro Sobajima, Akira Kobayashi, Masaaki Isoi
  • Patent number: 6180709
    Abstract: There is provided a thermoplastic resin composition comprising the following components (A) to (E): component (A): 50 to 74.7% by weight of a Ziegler-Natta catalyst sequentially polymerized blend of a propylene homopolymer and an ethylene-propylene copolymer, component (B): 5 to 10% by weight of an ethylene-octene random copolymer, component (C): 5 to 10% by weight of an ethylene-butene random copolymer, component (D): 0.3 to 5% by weight of an elastomer.
    Type: Grant
    Filed: May 15, 1998
    Date of Patent: January 30, 2001
    Assignees: Japan Polychem Corporation, Toyota Jidosha Kabushiki Kaisha
    Inventors: Takeyoshi Nishio, Takayuki Nagai, Hisayuki Iwai, Yukihito Zanka, Izumi Ishii, Hiroki Satoh, Yoshihiro Sobajima, Mitsuhiro Murayama
  • Patent number: 6040374
    Abstract: There is provided a propylene resin composition having an Izod impact strength (23.degree. C., notched) of not less than 5 kJ/m.sup.2 and a flexural modulus of not less than 500 MPa, wherein as measured by electron spectroscopy for chemical analysis, the ratio of the valence electron spectral intensity at a bond energy of 16.5 eV to the valence electron spectral intensity at a bond energy of 13.5 eV, I 16.5/I 13.5, is in the range of 1.6 to 2.0.There is also provided a method for evaluating a propylene resin composition, which comprises subjecting a propylene resin composition to electron spectroscopy for chemical analysis to measure the ratio of the valence electron spectral intensity at a bond energy of 16.5 eV to the valence electron spectral intensity at a bond energy of 13.5 eV, I 16.5/I 13.5; and evaluating, based on the ratio, the amount of a rubber component present on the surface of the composition.
    Type: Grant
    Filed: August 5, 1998
    Date of Patent: March 21, 2000
    Assignee: Japan Polychem Corporation
    Inventors: Yoshihiro Sobajima, Etsushi Akashige, Hironari Fujii, Akira Amano
  • Patent number: 6034177
    Abstract: There is provided a propylene resin composition consisting essentially of the following components (a) and (b):component (a): 100 parts by weight of a propylene-ethylene block copolymer composed of 60 to 80% by weight of crystalline polypropylene homopolymer moiety (unit A moiety), and 20 to 40% by weight of ethylene-propylene random copolymer moiety (unit B moiety) having an ethylene content of 30 to 60% by weight and a weight-average molecular weight (Mw) of 200,000 to 400,000, the melt flow rate of the component (a) being from 25 to 100g/10 min; andcomponent (b): 1 to 60 parts by weight of an ethylene-.alpha.-olefin copolymer rubber containing 20 to 50% by weight of an .alpha.-olefin having 3 to 16 carbon atoms.
    Type: Grant
    Filed: January 16, 1998
    Date of Patent: March 7, 2000
    Assignee: Japan Polychem Corporation
    Inventors: Yoshihiro Sobajima, Yuu Hayakawa
  • Patent number: 6015857
    Abstract: A propylene resin composition having excellent physical property balance (heat resistance and impact strength at low temperature), and excellent injection molding processability as well as excellent paintability is provided, which propylene resin composition comprises component (a): a propylene-ethylene block copolymer comprising 85-95% by weight of a crystalline polypropylene homopolymer portion (unit A) and 5-15% by weight of an ethylene-propylene random copolymer portion (unit B) having an ethylene content of 30-60% by weight, the melt flow rate of the total component (a) being 50-500 g/10 min in an amount of 100 parts by weight, component (b): talc having an average particle diameter of 1.5-10 .mu.m and an average aspect ratio of 4 or more in an amount of 10-60 parts by weight, and component (c): an ethylene-1-octene copolymer comprising 20-50% by weight of 1-octene, and having a density of 0.86-0.89 g/cm.sup.3 and a tensile strength at break of 10 MPa or more in an amount of 10-60 parts by weight.
    Type: Grant
    Filed: November 12, 1997
    Date of Patent: January 18, 2000
    Assignee: Japan Polychem Corporation
    Inventors: Yoshihiro Sobajima, Masashi Shimouse, Masahide Hamaura, Akira Yamaji
  • Patent number: 5990220
    Abstract: A propylene resin composition having suitability to coating is disclosed which comprises (a) 100 parts by weight of a propylene-ethylene block copolymer comprising 60 to 95% by weight of a crystalline polypropylene unit and 5 to 40% by weight of an ethylene-propylene random copolymer unit, (b) 2 to 120 parts by weight of an ethylene-.alpha.-olefin copolymer obtained by polymerization using a metallocene catalyst, containing 20 to 65% by weight of an .alpha.-olefin having 3 to 8 carbon atoms, and having a melt flow rate of 0.5 to 40 g/10 min and a density of 0.85 to 0.90 g/cm.sup.3, (c) 0.1 to 120 parts by weight of a filler selected from talc, mica, and a fibrous filler, (d) 5 to 40% by weight of a propylene polymer having grafted thereto 0.1 to 25% by weight, based on the total polymer, of maleic anhydride or a hydroxyl-containing maleic anhydride derivative, and (e) 0 to 10% by weight of a hydroxyl-terminated diene polymer or a hydrogenation product thereof.
    Type: Grant
    Filed: February 6, 1997
    Date of Patent: November 23, 1999
    Assignee: Japan Polychem Corporation
    Inventors: Yoshihiro Sobajima, Hironari Fujii, Masashi Shimouse
  • Patent number: 5747576
    Abstract: A propylene resin composition containing talc, comprising the following components (a), (b) and (c) is provided: (a) 100 parts by weight of a propylene/ethylene block copolymer containing a crystalline propylene homopolymer part (Unit A part) and an ethylene/propylene random copolymer part (Unit B part); (b) 0.1 to 80 parts by weight of talc having an average particle size of 1.5 to 20 microns and an average aspect ratio of not less than 4; and (c) 2 to 80 parts by weight of an ethylene/.alpha.-olefin copolymer polymerized by using a metallocene catalyst, and containing an .alpha.-olefin having 3 to 16 carbon atoms. This composition has good paintability, molding processability (fluidity) and excellent mechanical strength balance, and is useful for a material for e.g., automobile parts.
    Type: Grant
    Filed: September 17, 1997
    Date of Patent: May 5, 1998
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Yoshihiro Sobajima, Etsushi Akashige, Masahide Hamaura, Takeshi Hiramatsu, Akira Yamaji
  • Patent number: 5484835
    Abstract: There is provided a heat-resistant, propylene resin-based molding material, comprising the following components (A) and (B):component (A): 3 to 97% by weight of a resin-impregnated glass fiber bundle comprising:constituent (a.sup.1): 20 to 80 parts by weight of glass fibers having a length of at least 3 mm and an average diameter of 20 .mu.m or less, andconstituent (a.sup.2): 80 to 20 parts by weight of a crystalline propylene polymer at least partly modified with an unsaturated carboxylic acid or a derivative thereof, the MFR of the modified polymer being 50 g/10 min or more, in which the glass fibers are present in the constituent (a.sup.2) in such a state that they are arranged almost in parallel with one another; andcomponent (B): 97 to 3% by weight of a crystalline propylene polymer having an MFR of 50 g/10 min or more.
    Type: Grant
    Filed: May 31, 1994
    Date of Patent: January 16, 1996
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Yoshihiro Sobajima, Satoru Kinoshita, Masahide Hamaura
  • Patent number: 5432209
    Abstract: A propylene resin composition containing a propylene-ethylene block copolymer containing (a) a crystalline polypropylene moiety (constituent A) and an ethylene-propylene random copolymer moiety (constituent B), (b) a styrene-ethylene-butylene-styrene block copolymer which contains 10% to 25% of bound styrene, and (c) at least one filler selected from talc and inorganic whiskers and wherein the surface of the filler is treated with one of the organic compounds (I), (II) and (III) having the formulas, ##STR1## in which the various substituents and R groups are as defined in the specification and claims. The composition of the present invention has excellent mechanical strength, moldability and is capable of producing molded products having an excellent appearance.
    Type: Grant
    Filed: April 16, 1993
    Date of Patent: July 11, 1995
    Assignee: Mitsubishi Petrochemical Company Limited
    Inventors: Yoshihiro Sobajima, Keiko Kaba, Yoshihiro Noguchi
  • Patent number: 5296186
    Abstract: A process for producing a molded product of propylene resin which includes melting and kneading at least a part of the following component (a), adding to the resulting melt the following component (b) or the component (b) and the remainder of the component (a) and kneading the resulting mixture to prepare a resin composition having a melt flow rate of 1 to 100 g/10 min, and then molding the resin composition into a molded product in which the breakage rate of the component (b) is 30% by weight or less: (a) 100 parts by weight of a crystalline propylene polymer having a melt flow rate of 1 to 300 g/10 min and (b) 3 to 80 parts by weight of a filler in the form of hollow particles having a mean particle density (true density) of 0.1 to 0.9 g/cm.sup.3, as measured according to ASTM-D2840, a mean particle diameter of 7 to 100 .mu.m and a 10%-by-weight breakage pressure resistance of 100 kg/cm.sup.2 or more, as measured according to ASTM-D3102.
    Type: Grant
    Filed: February 12, 1993
    Date of Patent: March 22, 1994
    Assignee: Mitsubishi Petrochemical Company Limited
    Inventors: Yoshihiro Sobajima, Masahide Hamaura, Itsushi Imamura
  • Patent number: 4743651
    Abstract: A resin composition comprising a resin component comprising a polyphenylene ether resin and a polyamide resin, an aromatic vinyl compound-conjugated diene block copolymer, and a compound having an unsaturated group and a polar group in the molecule thereof. The composition is excellent in impact strength both at low temperature and room temperature, tensile elongation indicative of toughness, and organic solvent resistance.
    Type: Grant
    Filed: November 20, 1986
    Date of Patent: May 10, 1988
    Assignee: Mitsubishi Petrochemical Co., Ltd.
    Inventors: Nobuhiro Shibuya, Yoshihiro Sobajima, Hironari Sano
  • Patent number: 4603153
    Abstract: A glass fiber reinforced resin composition is described, comprising the following components: (a) 30 to 98 parts by weight of a crystalline propylene polymer; (b) 2 to 30 parts by weight of a glass fiber having an average diameter of 10.mu. or less, the amount of a binder deposited being from 0.01 to 0.3% by weight; (c) 0 to 35 parts by weight of an ethylene-based rubber; (d) 0 to 30 parts by weight of at least one inorganic filler selected from talc, mica, calcium silicate and glass powder; and (e) 0 to 10 parts by weight per 100 parts by weight of the sum of the components (a) to (d) of a pigment comprising a coloring component and a dispersing component, the proportion of a coloring matter or matters having a Mohs hardness of 3.5 or more in the coloring component being less than 30% by weight. This composition is superior in high temperature stiffness, appearance, and pelletizability, and is satisfactory in an amount of warp of article or re-heating warp, and impact strength.
    Type: Grant
    Filed: June 5, 1984
    Date of Patent: July 29, 1986
    Assignee: Mitsubishi Petrochemical Co., Ltd.
    Inventors: Yoshihiro Sobajima, Yukihiko Ichikawa
  • Patent number: 4552689
    Abstract: An inorganic filler containing propylene polymer composition which comprises 25 to 90% by weight of component (A) and 75 to 10% by weight of component (B):(A) at least one member selected from the group consisting of(a) a crystalline propylene copolymer composed of propylene and one or more other .alpha.-olefins;(b) a composition prepared by blending the copolymer (a) with a synthetic rubber and/or crystalline polypropylene; and(c) a composition prepared by blending a crystalline polypropylene with a synthetic rubber, wherein(1) the amount of xylene extractable soluble component at 23.degree. C. is 10 to 50% by weight, and(2) the propylene content in the extractable soluble component is 30% by weight or more,(B) an inorganic filler having an average particle size of 200.mu. or less, measured by light transmission in a liquid-phase sedimentation system.
    Type: Grant
    Filed: October 24, 1984
    Date of Patent: November 12, 1985
    Assignee: Mitsubishi Petrochemical Co., Ltd.
    Inventors: Hiroshi Yui, Yoshihiro Sobajima, Osamu Higashide, Tsuyoshi Imamura, Michiya Okamura, Satoru Hattori
  • Patent number: 4504617
    Abstract: An inorganic filler containing propylene polymer composition which comprises 25 to 90% by weight of component (A) and 75 to 10% by weight of component (B):(A) at least one member selected from the group consisting of(a) a crystalline propylene copolymer composed of propylene and one or more other .alpha.-olefins;(b) a composition prepared by blending the copolymer (a) with a synthetic rubber and/or crystalline polypropylene; and(c) a composition prepared by blending a crystalline polypropylene with a synthetic rubber, wherein(1) the amount of xylene extractable soluble component at 23.degree. C. is 10 to 50% by weight, and(2) the propylene content in the extractable soluble component is 30% by weight or more,(b) an inorganic filler having an average particle size of 200.mu. or less, measured by light transmission in a liquid-phase sedimentation system.
    Type: Grant
    Filed: September 16, 1982
    Date of Patent: March 12, 1985
    Assignee: Mitsubishi Petrochemical Co., Ltd.
    Inventors: Hiroshi Yui, Yoshihiro Sobajima, Osamu Higashide, Tsuyoshi Imamura, Michiya Okamura, Satoru Hattori
  • Patent number: 4244910
    Abstract: A method for molding a resin composition comprising a polyolefin and an inorganic filler to form a thin molded article, which comprises shooting said resin composition into a mold at such a high speed that its flow rate at the gate portion of the mold is at least 100 meters per second, thereby reducing the occurrence of short shots and the occurrence of mold flashing and making possible molding within a shorter period of time.
    Type: Grant
    Filed: September 25, 1979
    Date of Patent: January 13, 1981
    Assignee: Mitsubishi Petrochemical Co., Ltd.
    Inventors: Hiroshi Yui, Yoshihiro Sobajima, Ryoichi Ichikawa, Shigekazu Ema