Patents by Inventor Masayuki Tobita

Masayuki Tobita 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: 6761842
    Abstract: A method of manufacturing a heat conductive molded part having determined heat conductivity properties is provided. The method includes providing a polymer composition containing boron nitride powder. A magnetic field is impressed to the polymer composition containing boron nitride powder, field orienting the boron nitride powder in the polymer composition to a fixed direction. The polymer composition is set containing boron nitride powder with the boron nitride powder oriented in the polymer composition to the fixed direction. The polymer composition may also be provided containing a solvent. The solvent is removed after field orienting the boron nitride powder in the polymer composition to the fixed direction The composition is then set with the field oriented boron nitride powder after having removed the solvent.
    Type: Grant
    Filed: February 18, 2003
    Date of Patent: July 13, 2004
    Assignee: Polymatech Co., Ltd.
    Inventors: Masayuki Tobita, Shinya Tateda, Tsunehisa Kimura, Masahumi Yamato
  • Publication number: 20040102597
    Abstract: A thermally-conductive epoxy resin molded article conducting heat generated from electronic components and the like, and a method of manufacturing the same are disclosed. The thermally-conductive epoxy resin molded article according to the present invention is obtained by curing an epoxy resin composition containing an epoxy resin. The epoxy resin contained in the thermally-conductive epoxy resin molded article has the degree of orientation &agr; equal to or larger than 0.5 and smaller than 1.0.
    Type: Application
    Filed: October 14, 2003
    Publication date: May 27, 2004
    Inventors: Masayuki Tobita, Tsukasa Ishigaki, Toru Kimura, Naoyuki Shimoyama, Hisashi Aoki, Mitsukazu Ochi
  • Publication number: 20040087697
    Abstract: A mold product comprising liquid crystal composition for conducting heat.
    Type: Application
    Filed: October 14, 2003
    Publication date: May 6, 2004
    Inventors: Masayuki Tobita, Naoyuki Shimoyama, Tsukasa Ishigaki, Hisashi Aoki, Toru Kimura, Tsunehisa Kimura, Masafumi Yamato
  • Patent number: 6730731
    Abstract: A thermally conductive polymer composition includes polymer matrix such as thermoplastic resin or thermoplastic elastomer and a graphitized carbon fiber which serves as a thermally conductive filler. The graphitized carbon fiber is made from a mesophase pitch. The mesophase pitch is spun, infusibilized, carbonized, pulverized, and graphitized to form powdery graphitized carbon fibers. Preferably, the graphitized carbon fibers have a diameter of 5-20 &mgr;m, an average particle size of 10-500 &mgr;m, and a density of 2.20-2.26 g/cm3. The composition may be molded to form a thermally conductive molded article such as a thermally conductive sheet. The thermally conductive polymer composition and thermally conductive molded article have high thermal conductivity and transfer large amounts of heat from electric or electronic parts.
    Type: Grant
    Filed: August 31, 2001
    Date of Patent: May 4, 2004
    Assignee: Polymatech Co., LTD
    Inventors: Masayuki Tobita, Natsuko Ishihara, Naoyuki Shimoyama, Shinya Tateda
  • Patent number: 6723425
    Abstract: A thermally conductive molded article is produced by molding a conductive composition into a predetermined shape. The composition includes a polymer matrix and carbon powders. The carbon powders are obtained by graphitizing a polymeric material that has an aromatic ring on its main chain by heating. The carbon powders are aligned in a certain direction in the polymer matrix. Thus, the molded article can be produced easily and effectively that has excellent thermal conductivity in a given direction and that is suitable for use as a heat radiator, heat transfer member, or a component thereof in electronic hardware.
    Type: Grant
    Filed: June 4, 2002
    Date of Patent: April 20, 2004
    Assignee: Polymatech Co., Ltd.
    Inventors: Masayuki Tobita, Naoyuki Shimoyama, Shinya Tateda
  • Publication number: 20040048054
    Abstract: A thermal conductive polymer molded article is formed by molding a thermotropic liquid crystalline composition comprised mainly of a thermotropic liquid crystalline polymer, wherein the thermal conductive polymer molded article is formed by applying a magnetic field or an electric field to the thermotropic liquid crystalline composition melted by heating so that the thermal conductive polymer molded article has a first thermal conductivity (&lgr;1) higher than a second thermal conductivity (&lgr;2) of a molded article formed by molding the thermotropic liquid crystalline polymer without the application of the field. The thermal conductive polymer molded article preferably has a first thermal conductivity (&lgr;1) of between 0.7 and 20 W/(m·K). Preferably, the thermotropic liquid crystalline polymer comprises at least one polymer selected from (A) a wholly aromatic polyester and (B) a wholly aromatic polyester amide.
    Type: Application
    Filed: July 11, 2003
    Publication date: March 11, 2004
    Inventors: Masayuki Tobita, Toru Kimura, Naoyuki Shimoyama, Tsukasa Ishigaki
  • Patent number: 6652958
    Abstract: A thermally conductive polymer sheet includes a polymer matrix and graphitized carbon fibers as a thermally conductive filler. The graphitized carbon fibers are formed by spinning, infusibilization, carbonization, pulverized mesophase pitch before graphitizing the mesophase pitch. The graphitized carbon fibers have a coating layer of ferromagnetic material on their surface. The application of magnetic field to the coating layer allows the fibers to be oriented to be perpendicular to the sheet. Preferably, by X-ray diffractometry, the graphitized carbon fibers have an interplanar spacing (d002) of graphite planes of less than 0.3370 nm and a ratio (P101/P100) of diffraction peak (101) to diffraction peak (100) of at least 1.15. The ferromagnetic material is preferably at least one of a metal, an alloy, or a compound selected from the group consisting of nickel, cobalt and iron.
    Type: Grant
    Filed: October 16, 2001
    Date of Patent: November 25, 2003
    Assignee: Polymatech Co., Ltd.
    Inventor: Masayuki Tobita
  • Publication number: 20030194544
    Abstract: A thermally conductive formed article according to the present invention includes a matrix, and short carbon fibers which are present in the matrix. The short carbon fibers are oriented in a fixed direction in the matrix. A ratio I(002)/I(110) between an intensity I(110) of a diffraction peak ascribable to a (110) surface of carbon and an intensity I(002) of a diffraction peak ascribable to a (002) surface of carbon, occurring when X-rays are irradiated onto the thermally conductive formed article along the direction of orientation of the short carbon fibers, is 10 or less.
    Type: Application
    Filed: April 9, 2003
    Publication date: October 16, 2003
    Applicant: Polymatech Co., Ltd.
    Inventors: Masayuki Tobita, Naoyuki Shimoyama, Shinya Tateda, Tsunehisa Kimura, Masafumi Yamato
  • Publication number: 20030153665
    Abstract: A method of manufacturing a heat conductive molded part having determined heat conductivity properties is provided. The method includes providing a polymer composition containing boron nitride powder. A magnetic field is impressed to the polymer composition containing boron nitride powder, field orienting the boron nitride powder in the polymer composition to a fixed direction. The polymer composition is set containing boron nitride powder with the boron nitride powder oriented in the polymer composition to the fixed direction. The polymer composition may also be provided containing a solvent. The solvent is removed after field orienting the boron nitride powder in the polymer composition to the fixed direction The composition is then set with the field oriented boron nitride powder after having removed the solvent.
    Type: Application
    Filed: February 18, 2003
    Publication date: August 14, 2003
    Applicant: Polymatech Co., Ltd.
    Inventors: Masayuki Tobita, Shinya Tateda, Tsunehisa Kimura, Masahumi Yamato
  • Publication number: 20030096104
    Abstract: A complex molded body of carbon nanotubes includes a matrix and carbon nanotubes arranged in a given direction in the matrix. The matrix is at least one organic polymer selected from the group consisting of thermoplastic resin, thermosetting resin, rubber, and thermoplastic elastomer. The complex molded body is produced by a method comprising the step of: providing a composition that includes a matrix and carbon nanotubes; applying a magnetic field to the composition to arrange the carbon nanotubes in a given direction; and hardening the composition to produce a complex molded body. The complex molded body has excellent anisotropy in terms of electrical property, thermal property, and mechanical property.
    Type: Application
    Filed: March 14, 2002
    Publication date: May 22, 2003
    Applicant: Polymatech Co., Ltd.
    Inventors: Masayuki Tobita, Toru Kimura, Motoo Yumura, Satoshi Ohshima, Hiroki Ago, Kunio Uchida, Yozo Kakudate, Hiroyuki Yokoi
  • Publication number: 20030064017
    Abstract: A carbon fiber powder is produced by graphitizing a polymeric fiber having an aromatic ring on its main chain by heating and then pulverizing or cutting it. The polymeric fiber is selected from the group consisting of polybenzazole fiber, aromatic polyamide fiber, aromatic polyimide fiber, polyphenylene sulfide fiber, and wholly aromatic polyester fiber. The carbon fiber is preferably graphitized by heating the polymeric fiber at least 2500 degree C. under vacuum or in an inert gas. Thus, the carbon fiber powder that has excellent thermal conductivity and filling capability, a method of making the carbon fiber powder, and a thermally conductive composition including the carbon fiber powder are provided.
    Type: Application
    Filed: May 20, 2002
    Publication date: April 3, 2003
    Inventors: Masayuki Tobita, Naoyuki Shimoyama, Shinya Tateda
  • Publication number: 20030064216
    Abstract: Graphitized carbon powder are produced by carbonizing and expanding a pitch by heating to form carbonaceous foam and by graphitizing before pulverizing or graphitizing after pulverizing the carbonaceous foam. The resultant graphitized carbon powders have an interplanar spacing (d002) of graphite planes of less than 0.3370 nm. The powders preferably have an average particle size of from 2 to 200 &mgr;m. A thermally conductive composition includes the graphitized carbon powders in a matrix. The content of the powders is preferably 1 to 800 parts by weight relative to 100 parts by weight of the matrix. Thus, the graphitized carbon powders that have excellent thermal conductivity and a thermally conductive composition including such powders are provided.
    Type: Application
    Filed: September 26, 2002
    Publication date: April 3, 2003
    Inventors: Masayuki Tobita, Naoyuki Shimoyama, Shinya Tateda
  • Publication number: 20030003287
    Abstract: This invention relates to a heat conductive resin substrate which polybenzasol fibers are oriented in a thick direction and/or a direction of a surface of a resin substrate, further to the heat conductive resin substrate and a semiconductor package excellent in heat radiation ability which the semiconductor chips are mounted on the heat conductive resin substrate which the polybenzasol fibers are oriented in the thick direction (the Z direction) and/or the direction of the surface of the resin substrate, the heat conductive resin substance and the semiconductor package being provided with electrical insulation and high thermal conductivity, and being capable of controlling the thermal expansion coefficient.
    Type: Application
    Filed: April 18, 2002
    Publication date: January 2, 2003
    Applicant: POLYMATECH CO., LTD.
    Inventor: Masayuki Tobita
  • Publication number: 20020197923
    Abstract: A thermally conductive molded article is produced by molding a conductive composition into a predetermined shape. The composition includes a polymer matrix and carbon powders. The carbon powders are obtained by graphitizing a polymeric material that has an aromatic ring on its main chain by heating. The carbon powders are aligned in a certain direction in the polymer matrix. Thus, the molded article can be produced easily and effectively that has excellent thermal conductivity in a given direction and that is suitable for use as a heat radiator, heat transfer member, or a component thereof in electronic hardware.
    Type: Application
    Filed: June 4, 2002
    Publication date: December 26, 2002
    Inventors: Masayuki Tobita, Naoyuki Shimoyama, Shinya Tateda
  • Patent number: 6451418
    Abstract: This invention relates to a heat conductive resin substrate which polybenzasol fibers are oriented in a thick direction and/or a direction of a surface of a resin substrate, further to the heat conductive resin substrate and a semiconductor package excellent in heat radiation ability which the semiconductor chips are mounted on the heat conductive resin substrate which the polybenzasol fibers are oriented in the thick direction (the Z direction) and/or the direction of the surface of the resin substrate, the heat conductive resin substance and the semiconductor package being provided with electrical insulation and high thermal conductivity, and being capable of controlling the thermal expansion coefficient.
    Type: Grant
    Filed: March 22, 2000
    Date of Patent: September 17, 2002
    Assignee: Polymatech Co., Ltd.
    Inventor: Masayuki Tobita
  • Publication number: 20020090501
    Abstract: A thermally conductive polymer sheet includes a polymer matrix and graphitized carbon fibers as a thermally conductive filler. The graphitized carbon fibers are formed by spinning, infusibilization, carbonization, pulverized mesophase pitch before graphitizing the mesophase pitch. The graphitized carbon fibers have a coating layer of ferromagnetic material on their surface. The application of magnetic field to the coating layer allows the fibers to be oriented to be perpendicular to the sheet. Preferably, by X-ray diffractometry, the graphitized carbon fibers have an interplanar spacing (d002) of graphite planes of less than 0.3370 nm and a ratio (P101/P100) of diffraction peak (101) to diffraction peak (100) of at least 1.15. The ferromagnetic material is preferably at least one of a metal, an alloy, or a compound selected from the group consisting of nickel, cobalt and iron.
    Type: Application
    Filed: October 16, 2001
    Publication date: July 11, 2002
    Inventor: Masayuki Tobita
  • Publication number: 20020058743
    Abstract: A thermally conductive polymer composition includes polymer matrix such as thermoplastic resin or thermoplastic elastomer and a graphitized carbon fiber which serves as a thermally conductive filler. The graphitized carbon fiber is made from a mesophase pitch. The mesophase pitch is spun, infusibilized, carbonized, pulverized, and graphitized to form powdery graphitized carbon fibers. Preferably, the graphitized carbon fibers have a diameter of 5-20 &mgr;m, an average particle size of 10-500 &mgr;m, and a density of 2.20-2.26 g/cm3. The composition may be molded to form a thermally conductive molded article such as a thermally conductive sheet. The thermally conductive polymer composition and thermally conductive molded article have high thermal conductivity and transfer large amounts of heat from electric or electronic parts.
    Type: Application
    Filed: August 31, 2001
    Publication date: May 16, 2002
    Inventors: Masayuki Tobita, Natsuko Ishihara, Naoyuki Shimoyama, Shinya Tateda
  • Publication number: 20010004546
    Abstract: A heat conductive mold is provided in which boron nitride powder has a magnetic field which is oriented in a fixed direction within a polymer. The polymer is preferably at least one selected from silicon rubber, epoxy, Polyimide and polyurethane. The content of the boron nitride powder is from twenty-two 400 weight parts to 100 weight parts ofpolymer. A method is also provided in which a heat conductive mold of excellent heat conductivity is provided. The method includes impressing a magnetic field to the polymer composition containing boron nitride powder. The magnetic field impressed on the boron nitride powder, in the composition is impressed to have a fixed direction. The field is set after the direction is established. As an alternative, the method may include pressing the magnetic field to the polymer composition including the boron nitride powder and also a solvent.
    Type: Application
    Filed: December 8, 2000
    Publication date: June 21, 2001
    Inventors: Masayuki Tobita, Shinya Tateda, Tsunehisa Kimura, Masahumi Yamato
  • Patent number: 6166402
    Abstract: A double circular gate conductor 9 comprises a first circular gate conductor 7 connected to a gate electrode 2a, a second circular gate conductor 8, and a connecting conductor which connects the first circular gate conductor 7 and the second circular gate conductor 8, and is configured so as to equalize the voltage drop due to self-inductance or mutual inductance between the first circular gate conductor 7, second circular gate conductor 8 and cathode post electrode 4. In this manner it is possible to guarantee more or less uniform parallel inductance over the surface of the element.
    Type: Grant
    Filed: June 18, 1999
    Date of Patent: December 26, 2000
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kazuya Kodani, Toshiaki Matsumoto, Masayuki Tobita