Patents by Inventor Akira Nagatomi

Akira Nagatomi 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: 9761868
    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: Grant
    Filed: September 21, 2011
    Date of Patent: September 12, 2017
    Assignee: DOWA HOLDINGS CO., LTD.
    Inventor: Akira Nagatomi
  • Publication number: 20160043391
    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: October 19, 2015
    Publication date: February 11, 2016
    Inventor: Akira NAGATOMI
  • Patent number: 8629078
    Abstract: To provide an oxidation catalyst capable of burning PM of diesel engine exhausts gas at a low temperature, and hardly subjected to poisoning due to sulfur oxide. A composite oxide contains Ce, Bi, and M (wherein M is one or more elements selected from Mg, Ca, Sr, and Ba) and oxygen, and is manufactured, with a molar ratio of Ce, Bi, M expressed by Ce:Bi:M=(1?x?y):x:y, satisfying 0<x?0.4, and 0<y?0.4. This composite oxide is suitable as a PM combustion catalyst, and is hardly subjected to poisoning due to sulfur oxide.
    Type: Grant
    Filed: October 12, 2007
    Date of Patent: January 14, 2014
    Assignee: Dowa Electronics Materials Co., Ltd.
    Inventors: Yuki Kaneshiro, Takuya Yano, Akira Nagatomi
  • Patent number: 8524122
    Abstract: A production method capable of producing ITO particles without using a solvent with a high boiling point as a solvent used in the producing step by a simple treatment method without through a heating process in an atmosphere which disadvantageously causes sintering among the ITO particles to coarsen the ITO particles. An ITO powder suitable for a coating material for a transparent electroconductive material, being produced by a first step of dissolving salt containing indium and salt containing tin into an organic solvent, then adding to this organic solvent, an organic solvent containing a basic precipitant, to thereby manufacture a mixture of a precursor containing indium and tin, and the organic solvent; and a second step of applying heat treatment to the mixture of the precursor containing indium and tin, and the organic solvent in a pressurizing vessel at 200° C. or more and 300° C. or less, to generate ITO particles.
    Type: Grant
    Filed: June 30, 2009
    Date of Patent: September 3, 2013
    Assignees: Tohoku University, Dowa Electronics Materials Co., Ltd.
    Inventors: Atsushi Muramatsu, Kiyoshi Kanie, Kazuhisa Saito, Koji Tanoue, Akira Nagatomi
  • Patent number: 8512602
    Abstract: ITO particles are provided, which are small in variations of particle diameters and used for an ITO coating material capable of forming a transparent conductive film having high transparency and low haze value. Also, ITO coating material is provided, containing such ITO particles, and a transparent conductive film containing such ITO particles. Further, ITO powders are provided, wherein 90% or more of ITO particles constituting the ITO powders have a primary particle diameter of 20 nm or less.
    Type: Grant
    Filed: September 26, 2008
    Date of Patent: August 20, 2013
    Assignee: Dowa Electronics Materials Co., Ltd.
    Inventors: Akira Nagatomi, Koji Tanoue
  • 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
  • Patent number: 8475682
    Abstract: To provide a phosphor for manufacturing an one chip type LED illumination, etc, by combining a near ultraviolet/ultraviolet LED and a blue LED, and having an excellent emission efficiency including luminance. The phosphor is given as a general composition formula expressed by MmAaBbOoNn:Z, (where element M is one or more kinds of elements having bivalent valency, element A is one or more kinds of elements having tervalent valency, element B is one or more kinds of elements having tetravalent valency, O is oxygen, N is nitrogen, and element Z is one or more kinds of elements acting as an activator.), satisfying a=(1+x)×m, b=(4?x)×m, o=x×m, n=(7?x)×m, 0?x?1, wherein when excited by light in a wavelength range from 300 nm to 500 nm, the phosphor has an emission spectrum with a peak wavelength in a range from 500 nm to 620 nm.
    Type: Grant
    Filed: October 24, 2011
    Date of Patent: July 2, 2013
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Akira Nagatomi, Kenji Sakane, Tomoya Yamada
  • Patent number: 8441180
    Abstract: A phosphor having an excitation band relative to lights in the wide range of wavelengths from ultraviolet to visible light, and having an emission spectrum in the red range and so on, with a wide half value width, and an LED and a light source using the phosphor and emitting white and other color lights with good color rendering properties are provided. Powdered raw materials of Ca3N2 (2N), CaO (2N), AlN (3N), Si3N4 (3N), and Eu2O3 (3N) are prepared, and the respective raw materials are mixed to have a mole ratio of the respective elements of Ca:Al:Si:Eu=0.985:1:1:0.015. The mixed raw materials are fired at 1000° C. or higher in an inert atmosphere for three hours, and thereafter pulverized to obtain a phosphor having a composition of CaAlSiN2.83O0.25:Eu, which is one example of the phosphor satisfying the above described object.
    Type: Grant
    Filed: January 3, 2011
    Date of Patent: May 14, 2013
    Assignees: Dowa Electronics Materials Co., Ltd., Nichia Corporation
    Inventors: Akira Nagatomi, Masahiro Gotoh, Kenji Sakane, Shuji Yamashita
  • Patent number: 8372309
    Abstract: To provide a phosphor having an emission spectrum with a broad peak in a range from green color to yellow color, having a broad and flat excitation band capable of using lights of broad range from near ultraviolet/ultraviolet to blue lights as excitation lights, and having excellent emission efficiency and luminance. The problem is solved by providing the phosphor expressed by a general composition formula MmAaBbOoNn:Z (where element M is one or more kinds of elements having bivalent valency, element A is one or more kinds of elements having tervalent valency, element B is one or more kinds of elements having tetravalent valency, O is oxygen, N is nitrogen, and element Z is one or more kinds of elements acting as the activator), satisfying 4.0<(a+b)/m<7.0, a/m?0.5, b/a>2.5, n>o, n=2/3m+a+4/3b?2/3o, and having an emission spectrum with a peak wavelength of 500 nm to 650 nm when excited by light in a wavelength range from 300 nm to 500 nm.
    Type: Grant
    Filed: October 26, 2010
    Date of Patent: February 12, 2013
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Akira Nagatomi, Kenji Sakane
  • Publication number: 20130026908
    Abstract: Provided is the phosphor expressed by a general composition formula MmAaBbOoNn:Z (where element M is one or more kinds of elements having bivalent valency, element A is one or more kinds of elements having tervalent valency, element B is one or more kinds of elements having tetravalent valency, O is oxygen, N is nitrogen, and element Z is one or more kinds of activators.), satisfying 4.0<(a+b)/m<7.0, a/m?0.5, b/a>2.5, n>o, n=2/3m+a+4/3b?2/3o, and having an emission spectrum with a peak wavelength of 500 nm to 650 nm when excited by light in a wavelength range from 300 nm to 500 nm.
    Type: Application
    Filed: September 14, 2012
    Publication date: January 31, 2013
    Applicant: Mitsubishi Chemical Corporation
    Inventors: Akira NAGATOMI, Kenji Sakane
  • Patent number: 8308981
    Abstract: A phosphor, which is given by a general composition formula expressed by MmAaDdOoNn:Z, (wherein element M is at least one kind of element having bivalent valency, element A is at least one kind of element having tervalent valency selected from the group consisting of Al, Ga, In, Tl, Y, Sc, P, As, Sb, and Bi, element D is Si and/or Ge, O is oxygen, N is nitrogen, and element Z is at least one kind of element selected from rare earth elements or transitional metal elements, satisfying m>0, a>0, b>0 o?0, and n=2/3 m+a+4/3b?2/3o), where a content of the element Fe is smaller than 200 ppm.
    Type: Grant
    Filed: June 18, 2010
    Date of Patent: November 13, 2012
    Assignees: Dowa Electronics Materials Co., Ltd., Nichia Corporation
    Inventors: Akira Nagatomi, Shuji Yamashita, Tetsuya Ikuta
  • Publication number: 20120104317
    Abstract: To provide a phosphor for manufacturing an one chip type LED illumination, etc, by combining a near ultraviolet/ultraviolet LED and a blue LED, and having an excellent emission efficiency including luminance. The phosphor is given as a general composition formula expressed by MmAaBbOoNn:Z, (where element M is one or more kinds of elements having bivalent valency, element A is one or more kinds of elements having tervalent valency, element B is one or more kinds of elements having tetravalent valency, O is oxygen, N is nitrogen, and element Z is one or more kinds of elements acting as an activator.), satisfying a=(1+x)×m, b=(4?x)×m, o=x×m, n=(7?x)×m, 0?x?1, wherein when excited by light in a wavelength range from 300 nm to 500 nm, the phosphor has an emission spectrum with a peak wavelength in a range from 500 nm to 620 nm.
    Type: Application
    Filed: October 24, 2011
    Publication date: May 3, 2012
    Applicant: MITSUBISHI CHEMICAL CORPORATION
    Inventors: Akira NAGATOMI, Kenji SAKANE, Tomoya YAMADA
  • Patent number: 8071501
    Abstract: A composite oxide for exhaust gas purification catalysts, which comprises Ce, Bi, R and oxygen and satisfies 0<x?0.4 and 0<y<1.0 when the molar ratio of Ce, Bi and R of the oxide is represented as (1?x?y), x and Y respectively. The composite oxide has an X-ray diffraction peak corresponding to that of a fluorite structure. In the composite oxide, R contains one or two of Pr and Tb. The exhaust gas purification catalyst is favorable for a PM combustion catalyst.
    Type: Grant
    Filed: October 10, 2007
    Date of Patent: December 6, 2011
    Assignee: Dowa Electronics Materials Co., Ltd.
    Inventors: Yuki Kaneshiro, Akira Nagatomi
  • Patent number: 8066910
    Abstract: To provide a phosphor having an emission characteristic such that a peak wavelength of light emission is in a range from 580 to 680 nm, and having a high emission intensity, and having a flat excitation band with high efficiency for excitation light in a broad wavelength range from ultraviolet to visible light (wavelength range from 250 nm to 550 nm). For example, Ca3N2(2N), AlN(3N), Si3N4(3N), Eu2O3(3N) are prepared, and after weighing and mixing a predetermined amount of each raw material, raw materials are fired at 1500° C. for 6 hours, thus obtaining the phosphor including a product phase expressed by a composition formula CaAlSiN3:Eu and having an X-ray diffraction pattern satisfying a predetermined pattern.
    Type: Grant
    Filed: April 19, 2010
    Date of Patent: November 29, 2011
    Assignees: Dowa Electronics Materials Co., Ltd., Nichia Corporation
    Inventors: Kenji Sakane, Akira Nagatomi, Masahiro Gotoh, Shuji Yamashita
  • Patent number: 8062549
    Abstract: To provide a phosphor for manufacturing an one chip type LED illumination, etc, by combining a near ultraviolet/ultraviolet LED and a blue LED, and having an excellent emission efficiency including luminance. The phosphor is given as a general composition formula expressed by MmAaBbOoNn:Z, (where element M is one or more kinds of elements having bivalent valency, element A is one or more kinds of elements having tervalent valency, element B is one or more kinds of elements having tetravalent valency, O is oxygen, N is nitrogen, and element Z is one or more kinds of elements acting as an activator.), satisfying a=(1+x)×m, b=(4?x)×m, o=x×m, n=(7?x)×m, 0?x?1, wherein when excited by light in a wavelength range from 300 nm to 500 nm, the phosphor has an emission spectrum with a peak wavelength in a range from 500 nm to 620 nm.
    Type: Grant
    Filed: July 14, 2006
    Date of Patent: November 22, 2011
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Akira Nagatomi, Kenji Sakane, Tomoya Yamada
  • Patent number: 8048338
    Abstract: To provide a phosphor having a broad emission spectrum in a range of blue color (in a peak wavelength range from 400 nm to 500 nm), having a broad flat excitation band in a near ultraviolet/ultraviolet range, and having excellent emission efficiency and emission intensity/luminance. The phosphor is given as a general composition formula expressed by MmAaBbOoNn:Z, (where element M is the element having bivalent valency, element A is the element having tervalent valency, element B is the element having tetravalent valency, O is oxygen, N is nitrogen, and element Z is more than one kind of element acting as an activator), satisfying 5.0<(a+b)/m<9.0, 0?a/m?2.0, 0?o?n, n=2/3m+a+4/3b?2/3o, and has an emission spectrum with a maximum peak in the wavelength range from 400 nm to 500 nm under an excitation of the light in a wavelength range from 250 nm to 430 nm.
    Type: Grant
    Filed: March 30, 2006
    Date of Patent: November 1, 2011
    Assignees: Dowa Electronics Materials Co., Ltd., Mitsubishi Chemical Corporation
    Inventors: Akira Nagatomi, Kenji Sakane
  • Patent number: RE44162
    Abstract: To provide a phosphor for an electron beam excitation with a small deterioration in an emission efficiency and capable of maintaining a high luminance, even when an excitation density of an electron beam for a phosphor excitation is increased. As raw materials, Ca3N2(2N), AlN(3N), Si3N4(3N), and Eu2O3(3N) are prepared, and the raw materials thus prepared are measured and mixed, so that a molar ratio of each element becomes (Ca+Eu):Al:Si=1:1:1. Then, the mixture thus obtained is maintained and fired for at 1500° C. for 3 hours, and thereafter crushed, to manufacture the phosphor having a composition formula Ca0.985SiAlN3:Eu0.015.
    Type: Grant
    Filed: May 4, 2011
    Date of Patent: April 23, 2013
    Assignees: Dowa Electronics Materials Co., Ltd., Nichia Corporation
    Inventors: Masahiro Gotoh, Akira Nagatomi, Kenji Sakane, Shuji Yamashita
  • Patent number: RE44996
    Abstract: A phosphor including a main production phase of a phosphor expressed by a composition formula of MmAaBbOoNn:Zz (where an element M is one or more bivalent elements, an element A is one or more trivalent elements, an element B is one or more tetravalent elements, O is oxygen, N is nitrogen, an element Z is an activator, n=2/3m+a+4/3b?2/3o, m/(a+b)?1/2, (o+n)/(a+b)>4/3, wherein m=a=b=1 and o and n is not 0). A phosphor including 24 wt % to 30 wt % of Ca (calcium), 17 wt % to 21 wt % of Al (aluminum), 18 wt % to 22 wt % of Si (silicon), 1 wt % to 15 wt % of oxygen, 15 wt % to 33 wt % of nitrogen and 0.01 wt % to 10 wt % of Eu (europium), wherein an emission maximum in an emission spectrum is in a range of 600 nm to 660 nm; and wherein color chromaticity x of light emission is in a range of 0.5 to 0.7, and color chromaticity y of the light emission is in a range of 0.3 to 0.5.
    Type: Grant
    Filed: March 7, 2012
    Date of Patent: July 8, 2014
    Assignees: Nichia Corporation, Dowa Electronics Materials Co., Ltd.
    Inventors: Akira Nagatomi, Masahiro Gotoh, Kenji Sakane, Shuji Yamashita
  • Patent number: RE45502
    Abstract: To provide a phosphor having a broad emission spectrum with a peak in the range from yellow color to red color (wavelength from 570 nm to 620 nm), having a flat excitation band with large area on the long wavelength side from near ultraviolet/ultraviolet to green color (wavelength from 250 nm to 550 nm), and excellent in emission intensity and luminance, and a method of manufacturing the same, and also a light source such as white LED using the phosphor. As raw materials, Ca3N2(2N), AlN(3N), Si3N4(3N), and Eu2O3(3N) are prepared, and out of each raw material, 0.950/3 mol of Ca3N2, 2 mol of AlN, 4/3 mol of Si3N4, and 0.050/2 mol of Eu2O3 are weighed, and the raw materials thus weighed are mixed by using a mortar. The raw materials thus mixed are put in a BN crucible, and retained/fired for 3 hours at 1700° C. in a nitrogen atmosphere, and thereafter cooled from 1700° C. to 200° C., to thereby obtain the phosphor expressed by a composition formula Ca0.950Al2Si4O0.075N7.917:Eu0.050.
    Type: Grant
    Filed: March 7, 2012
    Date of Patent: May 5, 2015
    Assignees: Dowa Electronics Materials Co., Ltd., Nichia Corporation
    Inventors: Kenji Sakane, Akira Nagatomi
  • Patent number: RE45640
    Abstract: A phosphor, which has less reduction in emission efficiency and is capable of keeping high luminance even when density of an electron beam for exciting the phosphor increases, is provided. As raw materials, Ca3N2 (2N), AlN (3N), Si3N4 (3N), and Eu2O3 (3N) are prepared, and each of the raw materials is weighed so that a mole ratio of each element is, for example, (Ca+Eu):Al:Si=1:1:1, and mixed, then the mixture is held and fired at 1500° C. under the inert atmosphere for three hours, and thereafter ground to produce a phosphor having a composition formula of Ca0.985SiAlN3:Eu0.015.
    Type: Grant
    Filed: March 9, 2012
    Date of Patent: August 4, 2015
    Assignees: DOWA ELECTRONICS MATERIALS CO., LTD., NICHIA CORPORATION
    Inventors: Masahiro Gotoh, Akira Nagatomi, Kenji Sakane, Shuji Yamashita