Patents by Inventor Masahiro Gotoh

Masahiro Gotoh 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: 7291289
    Abstract: A phosphor with high efficiency having an excitation band corresponding to light of the ultraviolet-visible (300 to 550 nm) wavelength region emitted from a light emitting element which emits blue or ultraviolet light is provided. Commercially available CaO [3N], Si3N4 [3N], and Eu2O3 [3N] are prepared, respective materials are weighed and mixed to have a mol ratio of CaO:Si3N4:Eu2O3=1.4775:1:0.01125, and then the mixture is heated to 1600° C. by a heating rate of 15° C./min under a nitrogen atmosphere and retained and fired at 1600° C. for three hours. Thereafter, the raw materials are cooled down from 1600° C. to 200° C. for an hour to thereby produce a phosphor having a composition formula Ca1.58Si3O1.63N4.35:Eu0.024.
    Type: Grant
    Filed: August 20, 2004
    Date of Patent: November 6, 2007
    Assignee: Dowa Electronics Materials Co., Ltd.
    Inventors: Masahiro Gotoh, Akira Nagatomi, Kenji Sakane, Shuji Yamashita
  • Publication number: 20070228933
    Abstract: A light emitting device 10 includes: a lead frame 12a serving as a mounting portion having a cup 13; a light emitting element 14, mounted on the bottom face 13a of the cup, for emitting light having a predetermined peak wavelength; a layer of first phosphor particles 16, absorbed and formed on the light emitting element, for absorbing light emitted from the light emitting element and for emitting light having a longer peak wavelength than that of the light emitted from the light emitting element; second phosphor particles 18 for absorbing at least one of light emitted from the first phosphor particles and light emitted from the light emitting element and for emitting light having a longer peak wavelength than that of the at least one of the light emitted from the first phosphor particles and the light emitted from the light emitting element; and a sealing member 20, in which the second phosphor particles are dispersed, for sealing the light emitting element and the layer of first phosphor particles in the cup
    Type: Application
    Filed: March 26, 2007
    Publication date: October 4, 2007
    Applicant: DOWA ELECTRONICS MATERIALS CO., LTD.
    Inventors: Tsukasa Maruyama, Masahiro Gotoh, Tetsuya Ikuta
  • Publication number: 20070228949
    Abstract: A light emitting device 10 includes: a lead frame 12a serving as a mounting portion having a cup 13; a light emitting element 14, mounted on the bottom face 13a of the cup, for emitting light having a predetermined peak wavelength; a layer of large phosphor particles 16, absorbed and formed on the light emitting element, for absorbing light emitted from the light emitting element and for emitting light having a longer peak wavelength than that of the light emitted from the light emitting element; small phosphor particles 18, which have a smaller particle diameter than that of the large phosphor particles, for absorbing at least one of light emitted from the large phosphor particles and light emitted from the light emitting element and for emitting light having a longer peak wavelength than that of the at least one of the light emitted from the large phosphor particles and the light emitted from the light emitting element; and a sealing member 20, in which the small phosphor particles are dispersed, for sealin
    Type: Application
    Filed: March 27, 2007
    Publication date: October 4, 2007
    Applicant: DOWA ELECTRONICS MATERIALS CO., LTD.
    Inventors: Tsukasa Maruyama, Masahiro Gotoh, Tetsuya Ikuta
  • Patent number: 7273568
    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: August 20, 2004
    Date of Patent: September 25, 2007
    Assignee: Dowa Mining Co., Ltd.
    Inventors: Akira Nagatomi, Masahiro Gotoh, Kenji Sakane, Shuji Yamashita
  • Patent number: 7252788
    Abstract: A phosphor with high efficiency having an excitation band corresponding to light of the ultraviolet-visible (300 to 550 nm) wavelength region emitted from a light emitting portion which emits blue or ultraviolet light is provided. A nitride of Ca, a nitride of Al, a nitride Si, and an oxide of Eu are prepared, and respective raw materials are weighed so that a mol ratio of respective elements becomes Ca:Al:Si:Eu=0.985:3:1:0.015, mixed under a nitrogen atmosphere, and thereafter fired at 1500° C. in a nitrogen atmosphere to thereby produce a phosphor having a composition formula Ca0.985SiAlN3:Eu0.015.
    Type: Grant
    Filed: August 20, 2004
    Date of Patent: August 7, 2007
    Assignee: Dowa Mining Co., Ltd.
    Inventors: Akira Nagatomi, Kenji Sakane, Masahiro Gotoh, Shuji Yamashita
  • Publication number: 20070029525
    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: Application
    Filed: August 2, 2005
    Publication date: February 8, 2007
    Applicant: DOWA MINING CO., LTD.
    Inventors: Masahiro Gotoh, Akira Nagatomi, Kenji Sakane, Shuji Yamashita
  • Patent number: 7138756
    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.
    Type: Grant
    Filed: September 27, 2004
    Date of Patent: November 21, 2006
    Assignee: Dowa Mining Co., Ltd.
    Inventors: Masahiro Gotoh, Akira Nagatomi, Kenji Sakane, Shuji Yamashita
  • Publication number: 20060197432
    Abstract: To provide a phosphor mixture realizing a light emitting device having a phosphor and a light emission element, by which light emission is performed, with a small color shift due to a feeding current and having an excellent color rendering properties. CaAlSin3:Eu as a red phosphor and YAG:Ce as a yellow phosphor are manufactured, and emission spectra thereof are obtained. Meanwhile, the emission spectrum of an excitation light emitted by a light emitting part is obtained. From the emission spectra thus obtained, a relative mixing ratio of each phosphor is obtained by simulation, so that a correlated color temperature of the light emitting device becomes a target temperature. Then, based on the relative mixing ratio thus obtained, each phosphor is measured and mixed, and a phosphor mixture is thereby obtained.
    Type: Application
    Filed: August 8, 2005
    Publication date: September 7, 2006
    Applicant: DOWA MINING CO., LTD.
    Inventors: Akira Nagatomi, Masahiro Gotoh, Kenji Sakane
  • Publication number: 20060091790
    Abstract: To provide a light emitting device having a phosphor mixture and a light emitting part, the phosphor mixture including a red phosphor and more than one kind of phosphor having an emission spectrum with a peak in a wavelength range from 500 nm to 630 nm, and emitting light having a sufficient luminance and excellent in color rendering properties not only in a white light with high correlated color temperature, but also in a warm white light with low correlated color temperature. CaAlSiN3:Eu manufactured as a red phosphor and and CaAl2Si4N8:Eu manufactured as an orange phosphor, and for example, commercial YAG:Ce as a yellow-green phosphor, are prepared, and emission spectra of these phosphors are measured when excited by excitation light in the wavelength range from 430 nm to 500 nm.
    Type: Application
    Filed: February 22, 2005
    Publication date: May 4, 2006
    Applicant: DOWA MINING CO., LTD.
    Inventors: Akira Nagatomi, Masahiro Gotoh, Kenji Sakane
  • Publication number: 20060065878
    Abstract: To provide a phosphor having an emission spectrum with a broad peak in a range from yellow color to red color (580 nm to 680 nm) and an excellent excitation band on the longer wavelength side from near ultraviolet/ultraviolet of excitation light to visible light (250 nm to 550 nm), and having an improved emission intensity. The phosphor is provided, which is given by a general composition formula expressed by MmAaBbOoNn:Z, (wherein element M is more than one kind of element having bivalent valency, element A is more than 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 B is more than one kind of element having tetravalent valency, O is oxygen, N is nitrogen, and element Z is more than one kind of element selected from rare earth elements or transitional metal elements, satisfying m>0, a>0, b>0 o?0, and n=2/3m+a+4/3b?2/3o), and further containing boron and/or fluorine.
    Type: Application
    Filed: August 26, 2005
    Publication date: March 30, 2006
    Applicant: DOWA MINING CO., LTD.
    Inventors: Kenji Sakane, Akira Nagatomi, Masahiro Gotoh, Shuji Yamashita, Tetsuya Ikuta
  • Publication number: 20060045832
    Abstract: In order to provide a phosphor mixture which contains four or more kinds of phosphors comprising a red phosphor, an orange phosphor, a blue phosphor, and a green phosphor, and produce emission having excellent color rendering not only in the case of white light at a high color temperature, but also in the case of emission in warm white which is low in color temperature, and a light emitting device including the phosphor mixture and a light-emitting section, CaAlSiN3:Eu and CaAl2Si4N8:Eu are manufactured as a red phosphor and an orange phosphor respectively, and ZnS:Cu, Al, and BAM:Eu are prepared as a green phosphor and a blue phosphor respectively.
    Type: Application
    Filed: November 10, 2004
    Publication date: March 2, 2006
    Applicant: Dowa Mining Co., Ltd.
    Inventors: Akira Nagatomi, Masahiro Gotoh, Kenji Sakane
  • Publication number: 20060033083
    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: Application
    Filed: July 15, 2005
    Publication date: February 16, 2006
    Applicant: DOWA MINING CO., LTD.
    Inventors: Kenji Sakane, Akira Nagatomi, Masahiro Gotoh, Shuji Yamashita
  • Publication number: 20060022573
    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.
    Type: Application
    Filed: September 27, 2004
    Publication date: February 2, 2006
    Applicant: DOWA MINING CO., LTD.
    Inventors: Masahiro Gotoh, Akira Nagatomi, Kenji Sakane, Shuji Yamashita
  • Publication number: 20060017365
    Abstract: A phosphor of which emission wavelength can be optionally set in a region with high human visual sensitivity to make it possible to enhance lumlinance in the region, and which has an excitation band for light in a wavelength region emitted from the aforesaid light emitting portion, a production method of the same, illumination and an LED using the aforesaid phosphor are provided. As raw materials, for example, Ca3N2, CaO, Al2O3, AlN, Si3N4, and SiO2 an Eu2O3 are prepared, and each of the raw material is weighed so that a mole ratio of each element is, for example, (Ca, Eu): Al: Si=1:1:1, mixed and prepared under a nitrogen atmosphere, fired at 1500° C.
    Type: Application
    Filed: August 20, 2004
    Publication date: January 26, 2006
    Applicant: DOWA MINING CO., LTD.
    Inventors: Akira Nagatomi, Masahiro Gotoh, Kenji Sakane, Shuji Yamashita
  • Publication number: 20060006782
    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: Application
    Filed: September 2, 2004
    Publication date: January 12, 2006
    Applicant: DOWA MINING CO., LTD.
    Inventors: Akira Nagatomi, Masahiro Gotoh, Kenji Sakane, Shuji Yamashita
  • Publication number: 20050253500
    Abstract: A phosphor with high efficiency having an excitation band corresponding to light of the ultraviolet-visible (300 to 550 nm) wavelength region emitted from a light emitting element which emits blue or ultraviolet light is provided. Commercially available CaO [3N], Si3N4 [3N], and Eu2O3 [3N] are prepared, respective materials are weighed and mixed to have a mol ratio of CaO:Si3N4:Eu2O3=1.4775:1:0.01125, and then the mixture is heated to 1600° C. by a heating rate of 15° C./min under a nitrogen atmosphere and retained and fired at 1600° C. for three hours. Thereafter, the raw materials are cooled down from 1600° C. to 200° C. for an hour to thereby produce a phosphor having a composition formula Ca1.58Si3O1.63N4.35:Eu0.024.
    Type: Application
    Filed: August 20, 2004
    Publication date: November 17, 2005
    Applicant: DOWA MINING CO., LTD.
    Inventors: Masahiro Gotoh, Akira Nagatomi, Kenji Sakane, Shuji Yamashita
  • Publication number: 20050189863
    Abstract: A phosphor with high efficiency having an excitation band corresponding to light of the ultraviolet-visible (300 to 550 nm) wavelength region emitted from a light emitting portion which emits blue or ultraviolet light is provided. A nitride of Ca, a nitride of Al, a nitride QfSi, and an oxide of Eu are prepared, and respective raw materials are weighed so that a mol ratio of respective elements becomes Ca:Al:Si:Eu=0.985:3:1:0.015, mixed under a nitrogen atmosphere, and thereafter fired at 1500° C. in a nitrogen atmosphere to thereby produce a phosphor having a composition formula Ca0.985SiAlN3:Eu0.015.
    Type: Application
    Filed: August 20, 2004
    Publication date: September 1, 2005
    Applicant: DOWA MINING CO., LTD.
    Inventors: Akira Nagatomi, Kenji Sakane, Masahiro Gotoh, Shuji Yamashita
  • Patent number: 4910262
    Abstract: A novel block copolymer consisting essentially of ethylene and propylene and comprising 1 to 20 parts by weight of block (A) having an ethylene content of 0 to 4% by weight, 5 to 49 parts by weight of block (B) having an ethylene content of more than 4% and less than 25% by weight, and 50 to 94 parts by weight of block (C) having an ethylene content of 25 to 85% by weight. The block copolymer is characterized by less formation of flow marks in molding, and also has excellent tensile characteristics.
    Type: Grant
    Filed: January 25, 1989
    Date of Patent: March 20, 1990
    Assignee: Mitsubishi Petrochemical Company Limited
    Inventors: Masaki Fujii, Shiroh Gotoh, Masahiro Gotoh