Patents by Inventor Atsushi Tokuda

Atsushi Tokuda 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: 7612204
    Abstract: An object is to provide a novel organic compound capable of visible light emission. In particular, an object is to provide a novel organic compound that exhibits a broad emission spectrum when it is used for a light-emitting element. In addition, an object is to provide a light-emitting element and a light-emitting device that gives white light emission with an excellent color rendering property. The quinoxaline derivative represented by General Formula (1) is provided. Since the quinoxaline derivative represented by General Formula (1) is capable of emitting visible light, it can be favorably used for a light-emitting element. In particular, since the quinoxaline derivative represented by General Formula (1) exhibits a broad emission spectrum when it is used for a light-emitting element, by using it for a light-emitting element a light-emitting element that gives white light emission with an excellent color rendering property can be obtained.
    Type: Grant
    Filed: October 2, 2007
    Date of Patent: November 3, 2009
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Masakazu Egawa, Atsushi Tokuda
  • Patent number: 7601435
    Abstract: Target is to provide an organic compound material having a bipolar character. A quinoxaline derivative represented by a general formula (1) is provided. In the formula, R1-R12 each independently represents a hydrogen atom, a halogen atom, a lower alkyl group, an alkoxy group, an acyl group, a nitro group, a cyano group, an amino group, a dialkylamino group, a diarylamino group, a vinyl group, an aryl group, or a heterocyclic residue group. R9 and R10, R10 and R11, and R11 and R12 are each independent or respectively mutually bonded to form an aromatic ring. Ar1-Ar4 each independently represents an aryl group or a heterocyclic residue group. Ar1, Ar2, Ar3 and Ar4 are each independent or Ar1 and Ar2, and Ar3 and Ar4 are respectively mutually bonded directly, or Ar1 and Ar3, and Ar3 and Ar4 are bonded via oxygen (O), sulfur (S) or a carbonyl group.
    Type: Grant
    Filed: April 16, 2004
    Date of Patent: October 13, 2009
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Satoko Shitagaki, Atsushi Tokuda, Hiroko Abe, Ryoji Nomura, Satoshi Seo
  • Patent number: 7560177
    Abstract: A chelate complex having as its central metal tungsten which is an inexpensive metal and which is a heavy atom is applied to an organic light emitting element, thereby obtaining an organic light emitting element capable of converting the triplet excitation energy into light emission. By applying the organic light emitting element using this metal complex, an inexpensive light emitting device which is bright but consumes little power can be provided as well as an electric appliance using the light emitting device.
    Type: Grant
    Filed: August 21, 2006
    Date of Patent: July 14, 2009
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Satoshi Seo, Atsushi Tokuda, Yasuo Nakamura
  • Patent number: 7541098
    Abstract: A light-emitting organic compound that is superior in electrochemical stability, chemical stability, and thermal stability is provided. The compound also, shows blue luminescence with favorable color purity, and is represented by the following general formula (1). In the formula, X1 represents a silyl group in which one or more aryl groups having 5 to 10 carbon atoms are bound to silicon or an alkyl group having 1 to 4 carbon atoms. Ar1 represents an unsubstituted or substituted aryl group having 5 to 15 carbon atoms. Ar2 represents an aryl group having 5 to 20 carbon atoms, and may have a substituent at a site different from a binding site to Ar1.
    Type: Grant
    Filed: July 26, 2004
    Date of Patent: June 2, 2009
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Ryoji Nomura, Atsushi Tokuda, Hiroko Abe, Satoshi Seo
  • Publication number: 20090121626
    Abstract: A triplet light emitting device which has high efficiency and improved stability and which can be fabricated by a simpler process is provided by simplifying the device structure and avoiding use of an unstable material. In a multilayer device structure using no hole blocking layer conventionally used in a triplet light emitting device, that is, a device structure in which on a substrate, there are formed an anode, a hole transporting layer constituted by a hole transporting material, an electron transporting and light emitting layer constituted by an electron transporting material and a dopant capable of triplet light emission, and a cathode, which are laminated in the stated order, the combination of the hole transporting material and the electron transporting material and the combination of the electron transporting material and the dopant material are optimized.
    Type: Application
    Filed: December 16, 2008
    Publication date: May 14, 2009
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Hiroko YAMAZAKI, Atsushi TOKUDA, Tetsuo TSUTSUI
  • Patent number: 7485375
    Abstract: An EL element is provided in which a conjugate polymer that has a polythiophene derivative, a polyaniline derivative, a polypyrrole derivative or a polyfuran derivative as a fundamental skeleton and is soluble in an organic solvent is oxidized in its main chain with a dopant of an electron-accepting organic molecule that does not contain an acid component, and the doped conjugate polymer is used as a material to form a hole injecting layer. The polymer, being soluble in an organic solvent, can be formed in film even on a substrate high in the water repellency; that is, it can be easily formed in film on a TFT substrate and the like indispensable for an active matrix display device. Furthermore, since a dopant that does not contain an acid component is used, influence on an organic thin film and an electrode that are in contact with the hole injecting layer can be suppressed to the minimum level.
    Type: Grant
    Filed: December 16, 2003
    Date of Patent: February 3, 2009
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Atsushi Tokuda, Takako Takasu, Satoshi Seo, Ryoji Nomura
  • Patent number: 7482626
    Abstract: A triplet light emitting device which has high efficiency and improved stability and which can be fabricated by a simpler process is provided by simplifying the device structure and avoiding use of an unstable material. In a multilayer device structure using no hole blocking layer conventionally used in a triplet light emitting device, that is, a device structure in which on a substrate, there are formed an anode, a hole transporting layer constituted by a hole transporting material, an electron transporting and light emitting layer constituted by an electron transporting material and a dopant capable of triplet light emission, and a cathode, which are laminated in the stated order, the combination of the hole transporting material and the electron transporting material and the combination of the electron transporting material and the dopant material are optimized.
    Type: Grant
    Filed: October 29, 2007
    Date of Patent: January 27, 2009
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hiroko Yamazaki, Atsushi Tokuda, Tetsuo Tsutsui
  • Patent number: 7473575
    Abstract: A triplet light emitting device which has high efficiency and improved stability and which can be fabricated by a simpler process is provided by simplifying the device structure and avoiding use of an unstable material. In a multilayer device structure using no hole blocking layer conventionally used in a triplet light emitting device, that is, a device structure in which on a substrate, there are formed an anode, a hole transporting layer constituted by a hole transporting material, an electron transporting and light emitting layer constituted by an electron transporting material and a dopant capable of triplet light emission, and a cathode, which are laminated in the stated order, the combination of the hole transporting material and the electron transporting material and the combination of the electron transporting material and the dopant material are optimized.
    Type: Grant
    Filed: December 16, 2003
    Date of Patent: January 6, 2009
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hiroko Yamazaki, Atsushi Tokuda, Tetsuo Tsutsui
  • Patent number: 7413816
    Abstract: A white or whitish luminescent material for phosphorescence is provided by synthesizing an organometallic complex that is able to convert a triplet excited state into light emission. In particular, a white electroluminescent device that has a high luminous efficiency and can be manufactured easily is provided by using the organometallic complex to manufacture a white or whitish electroluminescent device. The electroluminescent device is used to provide a light-emitting device with low power consumption. A fluorescent and phosphorescent material represented by a general formula (2) is synthesized.
    Type: Grant
    Filed: December 17, 2003
    Date of Patent: August 19, 2008
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hideko Inoue, Satoshi Seo, Atsushi Tokuda, Ryoji Nomura
  • Publication number: 20080193794
    Abstract: It is an object to provide a new substance excellent in electron-transporting property, and a light-emitting element and a light-emitting device using the substance. A quinoxaline derivative represented by the general formula (G1) is provided. In the general formula (G1), each of R1 to R4 represents hydrogen, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 25 carbon atoms; and each of Ar1 and Ar2 represents an aryl group having 6 to 25 carbon atoms. Such a quinoxaline derivative is excellent in electron-transporting property and very effective as an electron-transporting material in a light-emitting element and the like.
    Type: Application
    Filed: September 24, 2007
    Publication date: August 14, 2008
    Inventors: Masakazu Egawa, Atsushi Tokuda, Satoko Shitagaki
  • Publication number: 20080143254
    Abstract: A triplet light emitting device which has high efficiency and improved stability and which can be fabricated by a simpler process is provided by simplifying the device structure and avoiding use of an unstable material. In a multilayer device structure using no hole blocking layer conventionally used in a triplet light emitting device, that is, a device structure in which on a substrate, there are formed an anode, a hole transporting layer constituted by a hole transporting material, an electron transporting and light emitting layer constituted by an electron transporting material and a dopant capable of triplet light emission, and a cathode, which are laminated in the stated order, the combination of the hole transporting material and the electron transporting material and the combination of the electron transporting material and the dopant material are optimized.
    Type: Application
    Filed: October 29, 2007
    Publication date: June 19, 2008
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hiroko Yamazaki, Atsushi Tokuda, Tetsuo Tsutsui
  • Publication number: 20080091012
    Abstract: An object is to provide a novel organic compound capable of visible light emission. In particular, an object is to provide a novel organic compound that exhibits a broad emission spectrum when it is used for a light-emitting element. In addition, an object is to provide a light-emitting element and a light-emitting device that gives white light emission with an excellent color rendering property. The quinoxaline derivative represented by General Formula (1) is provided. Since the quinoxaline derivative represented by General Formula (1) is capable of emitting visible light, it can be favorably used for a light-emitting element. In particular, since the quinoxaline derivative represented by General Formula (1) exhibits a broad emission spectrum when it is used for a light-emitting element, by using it for a light-emitting element, a light-emitting element that gives white light emission with an excellent color rendering property can be obtained.
    Type: Application
    Filed: October 2, 2007
    Publication date: April 17, 2008
    Inventors: Masakazu Egawa, Atsushi Tokuda
  • Publication number: 20080036369
    Abstract: According to the present invention, a light-emitting element, a light-emitting device, and a lighting system, each of which has a broad spectrum like sunlight and has high color rendering properties, can be obtained. One embodiment of the present invention has a light-emitting device which includes at least two kinds of luminescence center materials, and at least one kind of the luminescence center materials is a quinoxaline derivative represented by the following general formula (1): wherein R1 to R4 are individually hydrogen or an alkyl group having 6 carbon atoms (a straight-chain structure or a branch structure).
    Type: Application
    Filed: August 12, 2005
    Publication date: February 14, 2008
    Applicant: SEMICONDUCTOR ENERGY LABORSTORY CO., LTD.
    Inventors: Atsushi Tokuda, Masakuzu Egawa
  • Patent number: 7314769
    Abstract: Organometallic complexes represented by chemical formula 1 are synthesized. In chemical formula 1, R1 to R5, are individually a hydrogen atom, a halogen atom, a lower alkyl group, an alkoxy group, an acyl group, a nitro group, a cyano group, an amino group, a dialkylamino group, a diarylamino group, a vinyl group, an aryl group, or a heterocyclic group. Each pair of R1 and R2, R2 and R3, and R4 and R5 may be bonded each other to form aromatic rings. Y is a heterocyclic group containing nitrogen atoms as hetero atoms. M is atoms of group 9 in the periodic table or atoms of group 10 in the periodic table. When the M is atoms of group 9 in the periodic table, n=2. When the M is atoms of group 10 in the periodic table, n=1.
    Type: Grant
    Filed: August 25, 2004
    Date of Patent: January 1, 2008
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Satoshi Seo, Atsushi Tokuda, Hideko Inoue
  • Publication number: 20070278563
    Abstract: An object is to provide a nonvolatile semiconductor memory device which is excellent in a writing property and a charge retention property. In addition, another object is to provide a nonvolatile semiconductor memory device capable of reducing writing voltage. A nonvolatile semiconductor memory device includes a semiconductor layer or a semiconductor substrate including a channel formation region between a pair of impurity regions that are formed apart from each other, and a first insulating layer, a plurality of layers formed of different nitride compounds, a second insulating layer, and a control gate that are formed in a position which is over the semiconductor layer or the semiconductor substrate and overlaps with the channel formation region.
    Type: Application
    Filed: May 23, 2007
    Publication date: December 6, 2007
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Tamae Takano, Atsushi Tokuda, Ryota Tajima, Shunpei Yamazaki
  • Patent number: 7252895
    Abstract: The present invention is directed to a novel phosphorescent compound formed by synthesizing an orthometallated complex by using easily-synthesized ligands. The invention is further directed to an electroluminescent device having high luminous efficiency by using the phosphorescent compound. Moreover, the invention is also directed to a light-emitting device operating at a low voltage by using the electroluminescent device. According to the present invention, a phosphorescent compound represented by general formula [formula 1] is synthesized. Further, an electroluminescent device containing the phosphorescent compound is formed. In order to generate phosphorescent emission more efficiently, a heavy metal is preferably used as a central metal from the perspective of heavy atom effects.
    Type: Grant
    Filed: January 30, 2006
    Date of Patent: August 7, 2007
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Satoshi Seo, Hideko Inoue, Atsushi Tokuda, Ryoji Nomura
  • Patent number: 7232619
    Abstract: It is an object of the present invention to provide a pyrene derivative represented by the general formula (1) that is unlikely to crystallize and is superior in quality in the case of forming a film
    Type: Grant
    Filed: October 1, 2004
    Date of Patent: June 19, 2007
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Ryoji Nomura, Takako Takasu, Hiroko Abe, Atsushi Tokuda
  • Publication number: 20070054582
    Abstract: A method for manufacturing a display device of the present invention comprises the steps of forming insulating barriers which surround electrode and project upward from the surface of the electrode, and bringing the whole substrate into contact with water after applying the solution including an acceptor in wet process. According to the present invention, an organic conductive layer can be uniformly formed over a substrate in wet process even if the substrate does not have a smooth surface and has distribution in wettability of the surface.
    Type: Application
    Filed: September 25, 2006
    Publication date: March 8, 2007
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Atsushi Tokuda
  • Patent number: 7176307
    Abstract: Organometal complexes which are obtainable with a good yield by using a ligand which can be easily synthesized are provided. The organometal complexes are excellent in heat resistance. An electroluminescence element having high light emission efficiency is manufactured using the organometal complex. Therefore, the organometal complex represented by the general formula (1) is synthesized.
    Type: Grant
    Filed: December 28, 2005
    Date of Patent: February 13, 2007
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Satoshi Seo, Hideko Inoue, Atsushi Tokuda
  • Publication number: 20060280969
    Abstract: A chelate complex having as its central metal tungsten which is an inexpensive metal and which is a heavy atom is applied to an organic light emitting element, thereby obtaining an organic light emitting element capable of converting the triplet excitation energy into light emission. By applying the organic light emitting element using this metal complex, an inexpensive light emitting device which is bright but consumes little power can be provided as well as an electric appliance using the light emitting device.
    Type: Application
    Filed: August 21, 2006
    Publication date: December 14, 2006
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Satoshi Seo, Atsushi Tokuda, Yasuo Nakamura