Patents Assigned to Dowa Holdings Co., Ltd.
  • Patent number: 9673465
    Abstract: The present invention provides a catalyst in which a reaction initiation temperature at which self-heating function is exhibited is low and which is capable of suppressing carbon accumulation even when a reaction is repeated. The catalyst of the present invention includes a CeZr-based oxide, silicon, and a catalytically active metal, wherein the CeZr-based oxide satisfies CexZryO2 (x+y=1) and the silicon satisfies molar ratios of 0.02?Si/Zr and 0.01<Si/(Ce+Zr+Si)<0.2. When the catalyst is used, a reduction temperature for generating initial oxygen deficiency can be decreased. Depending on the catalytically active metal, a reduction activation treatment can be performed even at about 20° C. without any need for heating. In a repeated hydrogen generating reaction, the deposition of carbon generated on the surface of the catalyst can be suppressed, and a decrease in catalytic activity can be prevented.
    Type: Grant
    Filed: March 7, 2013
    Date of Patent: June 6, 2017
    Assignees: OITA UNIVERSITY, DOWA HOLDINGS CO., LTD.
    Inventors: Katsutoshi Nagaoka, Tatsuro Miyazaki, Takuya Yano, Kazumasa Ikari, Toshihiko Ueyama
  • Patent number: 9634327
    Abstract: In the case where a silicon substance having a high theoretical capacity as a negative electrode active material for a lithium ion secondary battery is used as a negative electrode active material, such a negative electrode active material is provided that has a high initial battery capacity and suffers less deterioration in performance even when many cycles of charge and discharge are repeated. A lithium ion secondary battery using the negative electrode active material is provided. Silicon and copper (II) oxide, or silicon, metallic copper and water are pulverized and simultaneously mixed in a pulverization device, thereby providing a negative electrode active material that has good cycle characteristics and a large battery capacity.
    Type: Grant
    Filed: July 8, 2015
    Date of Patent: April 25, 2017
    Assignees: TOHOKU UNIVERSITY, DOWA HOLDINGS CO., LTD.
    Inventors: Norihiro Shimoi, Kazuyuki Tohji, Yasumitsu Tanaka, Qiwu Zhang, Hiroyuki Kai
  • Publication number: 20160211519
    Abstract: Provided is an active material composite powder with which resistance can be reduced, and a method for manufacturing the active material composite powder. The active material composite powder includes an active material and lithium niobate attached onto the surface of the active material, and its BET specific surface area S [m2/g] is 0.93<S<1.44, and the method for manufacturing an active material composite powder includes a spraying and drying step of spraying a solution including lithium and a peroxo complex of niobium onto the active material and at the same time drying the solution, and a heating treatment step of carrying out a heating treatment after the spraying and drying step, wherein the temperature of the heating treatment is higher than 123° C. and lower than 350° C.
    Type: Application
    Filed: July 18, 2014
    Publication date: July 21, 2016
    Applicants: TOYOTA JIDOSHA KABUSHIKI KAISHA, DOWA HOLDINGS CO., LTD.
    Inventors: Takayuki UCHIYAMA, Nariaki MIKI, Yoshiaki AIKI, Koji TANOUE
  • Patent number: 9324556
    Abstract: A field electron emission film that is capable of being operated with low electric power and enhancing the uniformity in luminance within the light emission surface contains from 60 to 99.9% by mass of tin-doped indium oxide and from 0.1 to 20% by mass of carbon nanotubes. The film has a structure wherein grooves having a width in a range of from 0.1 to 50 mm are formed in a total extension of 2 mm or more per 1 mm2 on a surface of the film, and carbon nanotubes are exposed on a wall surface of the grooves. After forming an ITO film containing carbon nanotubes on a substrate, grooves are formed on a surface of the ITO film, and the end portions of the carbon nanotubes exposed to the wall surface of the grooves are designated as an emitter.
    Type: Grant
    Filed: August 12, 2013
    Date of Patent: April 26, 2016
    Assignees: TOHOKU UNIVERSITY, DOWA HOLDINGS CO., LTD.
    Inventors: Norihiro Shimoi, Kazuyuki Tohji, Yasumitsu Tanaka, Hiroyuki Kai
  • Patent number: 9132514
    Abstract: A solder powder having an average particle diameter of, for example, 0.05 ?m or more and less than 3 ?m is obtained by a method of producing a solder powder, including the steps of: putting solid or liquid metal, a non-aqueous solvent, and crushing balls having a diameter of 0.05 mm to 5 mm into a container to obtain a mixture; heating the mixture to 150° C. or higher and stirring the mixture; separating the crushing balls from the mixture after the stirring to obtain a mixture of the solder powder and the non-aqueous solvent; and performing solid-liquid separation on the mixture of the solder powder and the non-aqueous solvent to obtain a solder powder.
    Type: Grant
    Filed: November 18, 2010
    Date of Patent: September 15, 2015
    Assignee: DOWA HOLDINGS CO., LTD.
    Inventor: Yuichi Ishikawa
  • Publication number: 20150239758
    Abstract: There is provided a method of producing a radioactive cesium decontaminator, including: suspending magnetic particles in a solvent, and coating each magnetic particle with organic monomer or polymer, to thereby form a precursor; adding a ferrocyanide aqueous solution and an aqueous solution containing at least one kind of transition metal into a suspension liquid containing the precursor after coating while applying a strong shear force, to thereby generate a radioactive cesium decontaminator; and removing water content from a slurry containing the obtained radioactive cesium decontaminator.
    Type: Application
    Filed: September 10, 2013
    Publication date: August 27, 2015
    Applicants: THE JIKEI UNIVERSITY, DOWA HOLDING CO., LTD.
    Inventors: Yoshihisa Namiki, Toshihiko Ueyama, Takayuki Yoshida, Ryoei Watanabe
  • Publication number: 20150171448
    Abstract: The present invention provides a catalyst in which a reaction initiation temperature at which self-heating function is exhibited is low and which is capable of suppressing carbon accumulation even when a reaction is repeated. The catalyst of the present invention includes a CeZr-based oxide, silicon, and a catalytically active metal, wherein the CeZr-based oxide satisfies CexZryO2 (x+y=1) and the silicon satisfies molar ratios of 0.02?Si/Zr and 0.01<Si/(Ce+Zr+Si)<0.2. When the catalyst is used, a reduction temperature for generating initial oxygen deficiency can be decreased. Depending on the catalytically active metal, a reduction activation treatment can be performed even at about 20° C. without any need for heating. In a repeated hydrogen generating reaction, the deposition of carbon generated on the surface of the catalyst can be suppressed, and a decrease in catalytic activity can be prevented.
    Type: Application
    Filed: March 7, 2013
    Publication date: June 18, 2015
    Applicants: DOWA HOLDINGS CO., LTD., OITA UNIVERSITY
    Inventors: Katsutoshi Nagaoka, Tatsuro Miyazaki, Takuya Yano, Kazumasa Ikari, Toshihiko Ueyama
  • Patent number: 8888891
    Abstract: Disclosed is a method for recovery of a metal using plants. The method for recovery of a metal involves bringing a protonema of a moss plant belonging to the family Funariaceae into contact with a metal-containing solution in which a metal(s) having an ionization tendency lower than that of silver is dissolved.
    Type: Grant
    Filed: June 1, 2010
    Date of Patent: November 18, 2014
    Assignees: Riken, Dowa Holdings Co., Ltd.
    Inventors: Hitoshi Sakakibara, Misao Itouga, Yukari Komatsu, Satoshi Kawakami
  • Patent number: 8878189
    Abstract: An object of the present invention is to provide a Group III nitride semiconductor epitaxial substrate, a Group III nitride semiconductor element, and a Group III nitride semiconductor free-standing substrate, which have good crystallinity, with not only AlGaN, GaN, and GaInN the growth temperature of which is 1050° C. or less, but also with AlxGa1-xN having a high Al composition, the growth temperature of which is high; a Group III nitride semiconductor growth substrate used for producing these, and a method for efficiently producing those. The present invention provides a Group III nitride semiconductor growth substrate comprising a crystal growth substrate including a surface portion composed of a Group III nitride semiconductor which contains at least Al, and a scandium nitride film formed on the surface portion are provided.
    Type: Grant
    Filed: March 25, 2010
    Date of Patent: November 4, 2014
    Assignees: Dowa Holdings Co., Ltd., Dowa Electronics Materials Co., Ltd.
    Inventors: Ryuichi Toba, Masahito Miyashita, Tatsunori Toyota, Yoshitaka Kadowaki
  • Patent number: 8858909
    Abstract: There is provided a high-purity carbon nanotube, which can be produced with simple purification by causing graphite to be hardly contained in crude soot obtained immediately after being synthesized by arc-discharge, and a method for producing the same. Soot containing carbon nanotubes produced by arc-discharge using an anode which contains amorphous carbon as a main component is heated at a temperature of not lower than 350° C. to be burned and oxidized, immersed in an acid, heated at a temperature, which is not lower than the heating temperature in the previous burning and oxidation and which is not lower than 500° C., to be burned and oxidized, and immersed in an acid again.
    Type: Grant
    Filed: May 28, 2010
    Date of Patent: October 14, 2014
    Assignees: Dowa Holdings Co., Ltd., Tohoku University
    Inventors: Yoshinori Sato, Kazuyuki Tohji, Masaru Namura
  • Patent number: 8736025
    Abstract: An object of the present invention is to address the problems described herein and to provide a III-nitride semiconductor epitaxial substrate, a III-nitride semiconductor element, and a III-nitride semiconductor freestanding substrate, which have good crystallinity, not only with AlGaN, GaN, or GaInN, the growth temperature of which is at or below 1050° C., but also with AlxGa1-xN, the growth temperature of which is high and which has a high Al composition, as well as a III-nitride semiconductor growth substrate for fabricating these and a method for efficiently fabricating these. The invention is characterized by being equipped with: a crystal growth substrate, at least the surface portion of which substrate includes a III-nitride semiconductor containing Al; and a single metallic layer formed on the surface portion, the single metallic layer being made from Zr or Hf.
    Type: Grant
    Filed: December 25, 2009
    Date of Patent: May 27, 2014
    Assignees: Dowa Electroncs Materials Co., Ltd., Dowa Holdings Co., Ltd.
    Inventors: Ryuichi Toba, Masahito Miyashita, Tatsunori Toyota
  • Patent number: 8557020
    Abstract: A compound represented by General Formula (1) below, where R denotes a C1-C10 hydrocarbon group, Z denotes any one of a sulfide group, a sulfinyl group and a sulfonyl group, and n denotes an integer of 4 to 8 is described. A method for extracting metals and a metal recovery method using a metal extractant comprising the compound represented by General Formula (1) are also described.
    Type: Grant
    Filed: March 2, 2011
    Date of Patent: October 15, 2013
    Assignees: Dowa Holdings Co., Ltd., Akita University
    Inventors: Fumio Hamada, Chun-Bin Li, Yoshihiko Kondo
  • Publication number: 20130244034
    Abstract: A solder powder having an average particle diameter of, for example, 0.05 ?m or more and less than 3 ?m is obtained by a method of producing a solder powder, including the steps of: putting solid or liquid metal, a non-aqueous solvent, and crushing balls having a diameter of 0.05 mm to 5 mm into a container to obtain a mixture; heating the mixture to 150° C. or higher and stirring the mixture; separating the crushing balls from the mixture after the stirring to obtain a mixture of the solder powder and the non-aqueous solvent; and performing solid-liquid separation on the mixture of the solder powder and the non-aqueous solvent to obtain a solder powder.
    Type: Application
    Filed: November 18, 2010
    Publication date: September 19, 2013
    Applicant: DOWA HOLDINGS CO., LTD.
    Inventor: Yuichi Ishikawa
  • Publication number: 20130209890
    Abstract: There is provided a lithium-transition metal oxide powder with a coating layer containing lithium niobate formed on a part or the whole part of a surface of a lithium-transition metal oxide particle and having a low powder compact resistance, and a positive electrode active material for a lithium ion battery containing the lithium-transition metal oxide powder. Specifically, there is provided the lithium-transition metal oxide powder composed of a lithium-transition metal oxide particle with a part or the whole part of a surface coated with a coating layer containing lithium niobate, wherein a carbon-content is 0.03 mass % or less.
    Type: Application
    Filed: September 21, 2011
    Publication date: August 15, 2013
    Applicant: DOWA HOLDINGS CO., LTD.
    Inventor: Akira Nagatomi
  • Publication number: 20130137246
    Abstract: An object of the present invention is to provide a method for producing a Group III nitride semiconductor epitaxial substrate, a Group III nitride semiconductor element, and a Group III nitride semiconductor free-standing substrate, which have good crystallinity, with not only AlGaN, GaN, and GaInN the growth temperature of which is 1050° C. or less, but also with AlxGa1-xN having a high Al composition, the growth temperature of which is high; a Group III nitride semiconductor growth substrate used for producing these, and a method for efficiently producing those. The present invention provides a Group III nitride semiconductor growth substrate comprising a crystal growth substrate including a surface portion composed of a Group III nitride semiconductor which contains at least Al, and a scandium nitride film formed on the surface portion are provided.
    Type: Application
    Filed: January 25, 2013
    Publication date: May 30, 2013
    Applicants: DOWA ELECTRONICS MATERIALS CO., LTD., DOWA HOLDINGS CO., LTD.
    Inventors: DOWA Holdings Co., Ltd., DOWA Electronics Materials Co., Ltd.
  • Publication number: 20120083408
    Abstract: There is provided a high-purity carbon nanotube, which can be produced with simple purification by causing graphite to be hardly contained in crude soot obtained immediately after being synthesized by arc-discharge, and a method for producing the same. Soot containing carbon nanotubes produced by arc-discharge using an anode which contains amorphous carbon as a main component is heated at a temperature of not lower than 350° C. to be burned and oxidized, immersed in an acid, heated at a temperature, which is not lower than the heating temperature in the previous burning and oxidation and which is not lower than 500° C., to be burned and oxidized, and immersed in an acid again.
    Type: Application
    Filed: May 28, 2010
    Publication date: April 5, 2012
    Applicants: TOHOKU UNIVERSITY, DOWA HOLDINGS CO., LTD.
    Inventors: Yoshinori Sato, Kazuyuki Tohji, Masaru Namura
  • Publication number: 20120061683
    Abstract: An object of the present invention is to provide a Group III nitride semiconductor epitaxial substrate, a Group III nitride semiconductor element, and a Group III nitride semiconductor free-standing substrate, which have good crystallinity, with not only AlGaN, GaN, and GaInN the growth temperature of which is 1050° C. or less, but also with AlxGa1-xN having a high Al composition, the growth temperature of which is high; a Group III nitride semiconductor growth substrate used for producing these, and a method for efficiently producing those. The present invention provides a Group III nitride semiconductor growth substrate comprising a crystal growth substrate including a surface portion composed of a Group III nitride semiconductor which contains at least Al, and a scandium nitride film formed on the surface portion are provided.
    Type: Application
    Filed: March 25, 2010
    Publication date: March 15, 2012
    Applicants: DOWA ELECTRONICS MATERIALS CO., LTD., DOWA HOLDINGS CO., LTD.
    Inventors: Ryuichi Toba, Masahito Miyashita, Tatsunori Toyota, Yoshitaka Kadowaki
  • Patent number: 8124504
    Abstract: A GaN-based thin film (thick film) is grown using a metal buffer layer grown on a substrate. (a) A metal buffer layer (210) made of, for example, Cr or Cu is vapor-deposited on a sapphire substrate (120). (b) A substrate obtained by vapor-depositing the metal buffer layer (210) on the sapphire substrate (120) is nitrided in an ammonia gas ambient, thereby forming a metal nitride layer (212). (c) A GaN buffer layer (222) is grown on the nitrided metal buffer layers (210, 212). (d) Finally, a GaN single-crystal layer (220) is grown. This GaN single-crystal layer (220) can be grown to have various thicknesses depending on the objects. A freestanding substrate can be fabricated by selective chemical etching of the substrate fabricated by the above steps. It is also possible to use the substrate fabricated by the above steps as a GaN template substrate for fabricating a GaN-based light emitting diode or laser diode.
    Type: Grant
    Filed: January 21, 2010
    Date of Patent: February 28, 2012
    Assignees: Tohoku Techno Arch Co., Ltd., Furukawa Co., Ltd., Mitsubishi Chemical Corporation, Wavesquare Inc., Dowa Holdings Co., Ltd., Epivalley Co. Ltd.
    Inventors: Takafumi Yao, Meoung-Whan Cho
  • Patent number: 8119499
    Abstract: A semiconductor substrate fabrication method according to the first aspect of this invention is characterized by including a preparation step of preparing an underlying substrate, a stacking step of stacking, on the underlying substrate, at least two multilayered films each including a peeling layer and a semiconductor layer, and a separation step of separating the semiconductor layer.
    Type: Grant
    Filed: August 24, 2006
    Date of Patent: February 21, 2012
    Assignees: Tohoku Techno Arch Co., Ltd., Furukawa Co., Ltd., Mitsubishi Chemical Corporation, Dowa Holdings Co., Ltd., Epivalley Co., Ltd., Wavesquare Inc.
    Inventors: Takafumi Yao, Meoung-Whan Cho
  • Patent number: RE43924
    Abstract: Optical filter which is adapted to prevent the reflection of external light and improve a signal level of a signal sent from a display device by preventing attenuation thereof, and which is further adapted to prevent a change in hue of an image and to improve the hue, contrast and brightness of an image, thereby enhancing visibility. First, a liquid crystal display device (1) outputs light which is linearly polarized light. First linearly polarizing plate (2) is mounted in the filter in such a manner as to be adjusted to an axis of polarization of the linearly polarized light. Namely, the light outputted from the liquid crystal display device (1) passes through the first linearly polarizing plate (2) without being changed. The light passing through the first linearly polarizing plate (2) is then changed by a first quarter-wave phase difference plate (11) into circularly polarized light so that the phase difference between extraordinary light and ordinary light is (1/4) of the wavelength.
    Type: Grant
    Filed: August 19, 2010
    Date of Patent: January 15, 2013
    Assignee: Dowa Holdings Co., Ltd.
    Inventors: Takayuki Sawai, Teturo Ueno, Takashi Onioh, Shigeyoshi Inuyama, Kojyu Nagasaki