Patents by Inventor Takayuki Hirao

Takayuki Hirao 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: 9074033
    Abstract: The present invention provides an ethylene/tetrafluoroethylene copolymer showing good heat resistance and good crack resistance even in a high temperature environment. The present invention is an ethylene/tetrafluoroethylene copolymer, comprising: copolymerization units derived from ethylene; tetrafluoroethylene; and a fluorine-containing vinyl monomer represented by general formula: CH2?CH—Rf in the formula, Rf representing a perfluoroalkyl group containing four or more carbon atoms, a fluorine-containing vinyl monomer content being 0.8 to 2.5 mol % to a total amount of all monomers, an ethylene/tetrafluoroethylene molar ratio being 33.0/67.0 to 44.0/56.0, a CH index being 1.40 or less, a melting point being 230° C. or higher, and a melt flow rate being 40 (g/10 minutes) or less.
    Type: Grant
    Filed: April 20, 2010
    Date of Patent: July 7, 2015
    Assignee: DAIKIN INDUSTRIES, LTD.
    Inventors: Takayuki Hirao, Kenji Ichikawa, Shigehito Sagisaka, Yumi Nakano
  • Patent number: 9045844
    Abstract: A film 3 of a nitride of a group 13 element is grown on a seed crystal substrate 11 by flux process from a melt containing a flux and the group 13 element under nitrogen containing atmosphere. The film 3 of the nitride of the group 13 element includes an inclusion distributed layer 3a in a region distant from an interface 11a of the film 3 of the nitride of the group 13 element on the side of the seed crystal substrate 11 and containing inclusions derived from components of the melt, and an inclusion depleted layer 3b, with the inclusion depleted. provided on the layer 3a. Laser light A is irradiated from the side of the back face 1b of the seed crystal substrate 11 to peel the single crystal 3 of the nitride of the group 13 element from the seed crystal substrate 11 by laser lift-off method.
    Type: Grant
    Filed: January 29, 2014
    Date of Patent: June 2, 2015
    Assignee: NGK INSULATORS, LTD.
    Inventors: Makoto Iwai, Takayuki Hirao, Takashi Yoshino
  • Patent number: 9041004
    Abstract: A film 3 of a nitride of a group 13 element is grown on a seed crystal substrate 11 by flux process from a melt containing a flux and a group 13 element under nitrogen containing atmosphere. The film 3 of a nitride of a group 13 element includes an inclusion distributed layer 3a in a region distant from an interface of the film of a nitride of group 13 element on the side of the seed crystal substrate 11 and containing inclusions derived from components of the melt, and an inclusion depleted layer 3b, with the inclusion depleted. provided on the layer 3a.
    Type: Grant
    Filed: January 29, 2014
    Date of Patent: May 26, 2015
    Assignee: NGK Insulators, Ltd.
    Inventors: Makoto Iwai, Takayuki Hirao, Takashi Yoshino
  • Patent number: 8795431
    Abstract: A gallium nitride layer is produced using a seed crystal substrate by flux method. The seed crystal substrate 8A includes a supporting body 1, a plurality of seed crystal layers 4A each comprising gallium nitride single crystal and separated from one another, a low temperature buffer layer 2 provided between the seed crystal layers 4A and the supporting body and made of a nitride of a group III metal element, and an exposed layer 3 exposed to spaces between the adjacent seed crystal layers 4A and made of aluminum nitride single crystal or aluminum gallium nitride single crystal. The gallium nitride layer is grown on the seed crystal layers by flux method.
    Type: Grant
    Filed: September 20, 2013
    Date of Patent: August 5, 2014
    Assignee: NGK Insulators, Ltd.
    Inventors: Katsuhiro Imai, Makota Iwai, Takanao Shimodaira, Masahiro Sakai, Shuhei Higashihara, Takayuki Hirao
  • Publication number: 20140197420
    Abstract: A film 3 of a nitride of a group 13 element is grown on a seed crystal substrate 11 by flux process from a melt containing a flux and a group 13 element under nitrogen containing atmosphere. The film 3 of a nitride of a group 13 element includes an inclusion distributed layer 3a in a region distant from an interface of the film of a nitride of group 13 element on the side of the seed crystal substrate 11 and containing inclusions derived from components of the melt, and an inclusion depleted layer 3b, with the inclusion depleted. provided on the layer 3a.
    Type: Application
    Filed: January 29, 2014
    Publication date: July 17, 2014
    Applicant: NGK INSULATORS, LTD.
    Inventors: Makoto Iwai, Takayuki Hirao, Takashi Yoshino
  • Publication number: 20140158978
    Abstract: A semiconductor light emitting device includes a film of a nitride of a group 13 element grown on a seed crystal substrate by flux method from a melt including a flux and a group 13 element under nitrogen containing atmosphere, an n-type semiconductor layer provided on the film of the nitride, a light emitting region provided on the n-type semiconductor layer, and a p-type semiconductor layer provided on the light emitting region. The film includes an inclusion distributed layer in a region distant by 50 ?m or less from an interface of the film on the side of the seed crystal substrate and including inclusions derived from components of the melt, and an inclusion depleted layer with the inclusion depleted formed on the inclusion distributed layer.
    Type: Application
    Filed: February 7, 2014
    Publication date: June 12, 2014
    Applicant: NGK INSULATORS, LTD.
    Inventors: Makoto Iwai, Takayuki Hirao, Takashi Yoshino
  • Publication number: 20140147953
    Abstract: A film 3 of a nitride of a group 13 element is grown on a seed crystal substrate 11 by flux process from a melt containing a flux and the group 13 element under nitrogen containing atmosphere. The film 3 of the nitride of the group 13 element includes an inclusion distributed layer 3a in a region distant from an interface 11a of the film 3 of the nitride of the group 13 element on the side of the seed crystal substrate 11 and containing inclusions derived from components of the melt, and an inclusion depleted layer 3b, with the inclusion depleted. provided on the layer 3a. Laser light A is irradiated from the side of the back face 1b of the seed crystal substrate 11 to peel the single crystal 3 of the nitride of the group 13 element from the seed crystal substrate 11 by laser lift-off method.
    Type: Application
    Filed: January 29, 2014
    Publication date: May 29, 2014
    Applicant: NGK INSULATORS, LTD.
    Inventors: Makoto Iwai, Takayuki Hirao, Takashi Yoshino
  • Patent number: 8729672
    Abstract: To grow a gallium nitride crystal, a seed-crystal substrate is first immersed in a melt mixture containing gallium and sodium. Then, a gallium nitride crystal is grown on the seed-crystal substrate under heating the melt mixture in a pressurized atmosphere containing nitrogen gas and not containing oxygen. At this time, the gallium nitride crystal is grown on the seed-crystal substrate under a first stirring condition of stirring the melt mixture, the first stirring condition being set for providing a rough growth surface, and the gallium nitride crystal is subsequently grown on the seed-crystal substrate under a second stirring condition of stirring the melt mixture, the second stirring condition being set for providing a smooth growth surface.
    Type: Grant
    Filed: April 12, 2013
    Date of Patent: May 20, 2014
    Assignee: NGK Insulators, Ltd.
    Inventors: Takanao Shimodaira, Takayuki Hirao, Katsuhiro Imai
  • Publication number: 20140026809
    Abstract: A seed crystal substrate 10 includes a supporting body 1, and a seed crystal film 3A formed on the supporting body 1 and composed of a single crystal of a nitride of a Group 13 metal element. The seed crystal film 3A includes main body parts 3a and thin parts 3b having a thickness smaller than that of the main body parts 3a. The main body parts 3a and thin part 3b are exposed to a surface of the seed crystal substrate 10. A nitride 15 of a Group 13 metal element is grown on the seed crystal film 3A by flux method.
    Type: Application
    Filed: September 17, 2013
    Publication date: January 30, 2014
    Applicant: NGK INSULATORS, LTD.
    Inventors: Makoto Iwai, Takanao Shimodaira, Shuhei Higashihara, Takayuki Hirao, Masahiro Sakai, Katsuhiro Imai
  • Publication number: 20140031469
    Abstract: The present invention provides an aqueous fluoropolymer dispersion that shows favorable dispersion stability and is less likely to have a pH decrease even after storage for a long period of time. The present invention provides an aqueous fluoropolymer dispersion including: a fluoropolymer; a fluorine free surfactant; at least one organic electrolyte selected from the group consisting of hydroxy monocarboxylic acids, hydroxy dicarboxylic acids, tricarboxylic acids, and amino acids; and a fluorine-containing anionic surfactant containing not more than 7 carbon atoms.
    Type: Application
    Filed: March 29, 2012
    Publication date: January 30, 2014
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Kenjiro Tanimoto, Junya Iida, Takeshi Shimono, Takayuki Hirao, Nobuhiko Tsuda, Taketo Kato
  • Publication number: 20140014028
    Abstract: A gallium nitride layer is produced using a seed crystal substrate by flux method. The seed crystal substrate 8A includes a supporting body 1, a plurality of seed crystal layers 4A each comprising gallium nitride single crystal and separated from one another, a low temperature buffer layer 2 provided between the seed crystal layers 4A and the supporting body and made of a nitride of a group III metal element, and an exposed layer 3 exposed to spaces between the adjacent seed crystal layers 4A and made of aluminum nitride single crystal or aluminum gallium nitride single crystal. The gallium nitride layer is grown on the seed crystal layers by flux method.
    Type: Application
    Filed: September 20, 2013
    Publication date: January 16, 2014
    Applicant: NGK INSULATORS, LTD.
    Inventors: Katsuhiro Imai, Makoto Iwai, Takanao Shimodaira, Masahiro Sakai, Shuhei Higashihara, Takayuki Hirao
  • Patent number: 8440017
    Abstract: To grow a gallium nitride crystal, a seed-crystal substrate is first immersed in a melt mixture containing gallium and sodium. Then, a gallium nitride crystal is grown on the seed-crystal substrate under heating the melt mixture in a pressurized atmosphere containing nitrogen gas and not containing oxygen. At this time, the gallium nitride crystal is grown on the seed-crystal substrate under a first stirring condition of stirring the melt mixture, the first stirring condition being set for providing a rough growth surface, and the gallium nitride crystal is subsequently grown on the seed-crystal substrate under a second stirring condition of stirring the melt mixture, the second stirring condition being set for providing a smooth growth surface.
    Type: Grant
    Filed: August 12, 2011
    Date of Patent: May 14, 2013
    Assignee: NGK Insulators, Ltd.
    Inventors: Takanao Shimodaira, Takayuki Hirao, Katsuhiro Imai
  • Patent number: 8334351
    Abstract: An FEP pellet having a volatile content of 0.2% by weight or less. The FEP pellet satisfies the following requirements (i) and (ii) when used to form a insulating material coating a core wire by extrusion coating at a coating speed of 2,800 ft/min.: (i) an adhesive strength between the insulating material and said core wire of 0.8 kg or more; and (ii) an average number of cone-breaks in the insulating material of one or less per 50,000 feet of the coated core wire.
    Type: Grant
    Filed: March 2, 2011
    Date of Patent: December 18, 2012
    Assignee: Daikin Industries, Ltd.
    Inventors: Hideki Kono, Takayuki Hirao, George Lin, Kazuyuki Fukuda
  • Patent number: 8247137
    Abstract: Separators (5A, 5B, 6) and membrane-electrode assemblies (2) of a fuel cell stack (1) are alternately stacked in a guide box (40). The separators (5A, 5B, 6) each have groove-like gas paths (10A, 10B). Powder of an adhesive agent (7) is adhered in advance to the surfaces of the separators (5A, 5B, 6), except the gas paths (10A, 10B), through photosensitive drums (31A, 31B) to which the powder is adsorbed in a given pattern. The separators (5A, 5B, 6) and the membrane-electrode assemblies (2), stacked in the guide box (40), are heated and compressed by a press (43) and heaters (40C) to obtain a unitized fuel cell stack (1).
    Type: Grant
    Filed: June 10, 2011
    Date of Patent: August 21, 2012
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Akira Fujiki, Yukihiro Maekawa, Takeharu Kuramochi, Masahiko Katsu, Takayuki Hirao, Takeshi Shimizu, Masanori Iwamoto, Sadao Miki, Haruhiko Suzuki, Yoshiki Muto, Kaoru Eguchi, Masahiro Omata, Hiroshi Saitou
  • Publication number: 20120175740
    Abstract: Regarding a base substrate, a plurality of steps are formed stepwise on the principal surface (c-face). Each step has a height difference of 10 to 40 ?m, and an edge is formed parallel to an a-face of a hexagonal crystal of GaN. Meanwhile, the terrace width of each step is set at a predetermined width. The predetermined width is set in such a way that after a GaN crystal is grown on the principal surface of the base substrate, the principal surface is covered up with grain boundaries when the grown GaN crystal is observed from the surface side. The plurality of steps can be formed through, for example, dry etching, sand blasting, lasing, and dicing.
    Type: Application
    Filed: October 15, 2010
    Publication date: July 12, 2012
    Inventors: Takayuki Hirao, Takanao Shimodaira, Katsuhiro Imai
  • Publication number: 20120111601
    Abstract: The present invention provides a composition including a fluorine-containing polymer, and excellent in heat resistance even if only a small amount of additives is added to the composition. The present invention relates to a composition, comprising: a fluorine-containing polymer (a) and a cobalt compound (b).
    Type: Application
    Filed: June 17, 2010
    Publication date: May 10, 2012
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Yasukazu Nakatani, Toshio Miyatani, Hiroshi Torii, Natsumi Okamoto, Takayuki Hirao, Manabu Fujisawa, Shigehito Sagisaka
  • Publication number: 20120037398
    Abstract: The present invention provides an ethylene/tetrafluoroethylene copolymer showing good heat resistance and good crack resistance even in a high temperature environment. The present invention is an ethylene/tetrafluoroethylene copolymer, comprising: copolymerization units derived from ethylene; tetrafluoroethylene; and a fluorine-containing vinyl monomer represented by general formula: CH2=CH?Rf in the formula, Rf representing a perfluoroalkyl group containing four or more carbon atoms, a fluorine-containing vinyl monomer content being 0.8 to 2.5 mol % to a total amount of all monomers, an ethylene/tetrafluoroethylene molar ratio being 33.0/67.0 to 44.0/56.0, a CH index being 1.40 or less, a melting point being 230° C. or higher, and a melt flow rate being 40 (g/10 minutes) or less.
    Type: Application
    Filed: April 20, 2010
    Publication date: February 16, 2012
    Applicant: Daikin Industries Ltd.
    Inventors: Takayuki Hirao, Kenji Ichikawa, Shigehito Sagisaka, Yumi Nakano
  • Publication number: 20120012984
    Abstract: To grow a gallium nitride crystal, a seed-crystal substrate is first immersed in a melt mixture containing gallium and sodium. Then, a gallium nitride crystal is grown on the seed-crystal substrate under heating the melt mixture in a pressurized atmosphere containing nitrogen gas and not containing oxygen. At this time, the gallium nitride crystal is grown on the seed-crystal substrate under a first stirring condition of stirring the melt mixture, the first stirring condition being set for providing a rough growth surface, and the gallium nitride crystal is subsequently grown on the seed-crystal substrate under a second stirring condition of stirring the melt mixture, the second stirring condition being set for providing a smooth growth surface.
    Type: Application
    Filed: August 12, 2011
    Publication date: January 19, 2012
    Applicant: NGK Insulators, Ltd.
    Inventors: Takanao SHIMODAIRA, Takayuki Hirao, Katsuhiro Imai
  • Publication number: 20110287222
    Abstract: A sapphire substrate on a surface of which a thin film of gallium nitride is formed is prepared as a seed-crystal substrate and placed in a growth vessel. Gallium and sodium metals are weighed to achieve a molar ratio of 25 to 32:68 to 75 and added into the vessel. The vessel is put into a reaction vessel. An inlet pipe is connected to the reaction vessel. Nitrogen gas is introduced from a nitrogen tank through a pressure controller to fill the reaction vessel. While the internal pressure of the reaction vessel is controlled to be a predetermined nitrogen gas pressure and target temperatures are set such that the temperature of a lower heater is higher than the temperature of an upper heater, a gallium nitride crystal is grown. As a result, a group 13 nitride crystal having a large grain size and a low dislocation density is provided.
    Type: Application
    Filed: July 21, 2011
    Publication date: November 24, 2011
    Applicant: NGK Insulators, Ltd.
    Inventors: Takayuki Hirao, Makoto Iwai, Katsuhiro Imai
  • Publication number: 20110274609
    Abstract: A group 13 nitride crystal substrate according to the present invention is produced by growing a group 13 nitride crystal on a seed-crystal substrate by a flux method, wherein a content of inclusions in the group 13 nitride crystal grown in a region of the seed-crystal substrate except for a circumferential portion of the seed-crystal substrate, the region having an area fraction of 70% relative to an entire area of the seed-crystal substrate, is 10% or less, preferably 2% or less.
    Type: Application
    Filed: July 15, 2011
    Publication date: November 10, 2011
    Applicant: NGK Insulators, Ltd.
    Inventors: Takanao Shimodaira, Katsuhiro Imai, Makoto Iwai, Takayuki Hirao