Patents by Inventor Masaki Hirakata

Masaki Hirakata 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: 10073364
    Abstract: Electrophotographic photoreceptor including a conductive substrate, an organic photosensitive layer on an outer peripheral surface of the conductive substrate, and an inorganic protective layer on an outer peripheral surface of the organic photosensitive layer, the inorganic protective layer containing gallium and oxygen. A volume resistivity of an inner region of the inorganic protective layer, the inner region extending 0.2 ?m or about 0.2 ?m from an inner peripheral surface of the inorganic protective layer in a thickness direction, and a volume resistivity of an outer region of the inorganic protective layer, the outer region extending 0.2 ?m or about 0.2 ?m from an outer peripheral surface of the inorganic protective layer in the thickness direction, are both 6.0×107 ?·cm or more and 4.0×108 ?·cm or less or about 6.0×107 ?·cm or more and about 4.0×108 ?·cm or less.
    Type: Grant
    Filed: July 12, 2017
    Date of Patent: September 11, 2018
    Assignee: FUJI XEROX CO., LTD.
    Inventors: Yoichi Kigoshi, Masaki Hirakata, Satomi Kashiwagi, Nobuyuki Torigoe, Takeshi Iwanaga, Takashi Imai
  • Patent number: 10001714
    Abstract: An electrophotographic photosensitive member includes a conductive base; an organic photosensitive layer disposed on the conductive base, the organic photosensitive layer including a layer that constitutes a surface and contains a charge transport material, a binder resin having a viscosity-average molecular weight less than about 50,000, and silica particles in an amount of about 40% by weight or more; and an inorganic protective layer disposed on the organic photosensitive layer.
    Type: Grant
    Filed: January 15, 2016
    Date of Patent: June 19, 2018
    Assignee: FUJI XEROX CO., LTD.
    Inventors: Masaki Hirakata, Takeshi Iwanaga, Nobuyuki Torigoe, Hideya Katsuhara, Yoichi Kigoshi, Takashi Imai, Fumiaki Mera
  • Publication number: 20180095372
    Abstract: Electrophotographic photoreceptor including a conductive substrate, an organic photosensitive layer on an outer peripheral surface of the conductive substrate, and an inorganic protective layer on an outer peripheral surface of the organic photosensitive layer, the inorganic protective layer containing gallium and oxygen. A volume resistivity of an inner region of the inorganic protective layer, the inner region extending 0.2 ?m or about 0.2 ?m from an inner peripheral surface of the inorganic protective layer in a thickness direction, and a volume resistivity of an outer region of the inorganic protective layer, the outer region extending 0.2 ?m or about 0.2 ?m from an outer peripheral surface of the inorganic protective layer in the thickness direction, are both 6.0×107 ?·cm or more and 4.0×108 ?·cm or less or about 6.0×107 ?·cm or more and about 4.0×108 ?·cm or less.
    Type: Application
    Filed: July 12, 2017
    Publication date: April 5, 2018
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Yoichi KIGOSHI, Masaki HIRAKATA, Satomi KASHIWAGI, Nobuyuki TORIGOE, Takeshi IWANAGA, Takashi IMAI
  • Publication number: 20180067443
    Abstract: An image forming apparatus includes an electrophotographic photoreceptor, a charging device, an electrostatic latent image forming device, a developing device, a transfer device, and a cleaning device, and further includes an intercepting device that includes an intercepting member separated from the electrophotographic photoreceptor by a gap so that a distance from the surface of the electrophotographic photoreceptor to the intercepting member is about 0.3 to 0.9 (inclusive) times a volume-average particle size of toner particles. The intercepting member is used to intercept residual toner particles at a position downstream of the transfer device and upstream of the cleaning device in a rotation direction of the electrophotographic photoreceptor, the residual toner particles remaining on the surface of the electrophotographic photoreceptor.
    Type: Application
    Filed: March 8, 2017
    Publication date: March 8, 2018
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Masaki HIRAKATA, Takashi IMAI
  • Patent number: 9904204
    Abstract: A unit for an image forming apparatus includes an electrophotographic photoreceptor that includes a conductive substrate, a photosensitive layer provided on the conductive substrate, and a surface layer provided so as to contact with an outermost surface of the photosensitive layer, and an exposure section that exposes the electrophotographic photoreceptor with a light having a wavelength (?) (nm) so as to form an electrostatic latent image on a charged surface of the electrophotographic photoreceptor, wherein a surface roughness (Rz1) (nm) of the outermost surface of the photosensitive layer satisfies an expression of [(Rz1)?(?)/(4×(n2))] where a refractive index of the surface layer is set as (n2), and an outermost surface of the surface layer has a surface shape different from the outermost surface of the photosensitive layer.
    Type: Grant
    Filed: February 4, 2016
    Date of Patent: February 27, 2018
    Assignee: FUJI XEROX CO., LTD.
    Inventors: Takeshi Iwanaga, Takashi Imai, Hideya Katsuhara, Masaki Hirakata, Yoichi Kigoshi, Nobuyuki Torigoe, Fumiaki Mera
  • Patent number: 9864286
    Abstract: An electrophotographic photoreceptor includes an electroconductive substrate, an organic photosensitive layer on the electroconductive substrate and an inorganic protective layer on the organic photosensitive layer, wherein a layer that forms a surface of the organic photosensitive layer contains a charge transporting material, a binder resin, and a silica particle; the inorganic protective layer contains a group 13 element, an oxygen atom, and a hydrogen atom; a sum of element constitution ratios of the group 13 element, the oxygen atom, and the hydrogen atom to all elements constituting the inorganic protective layer is equal to or more than 90 atomic %; and an element composition ratio (oxygen atom/group 13 element) of the oxygen atom and the group 13 element is 1.0 or more and less than 1.5.
    Type: Grant
    Filed: July 8, 2016
    Date of Patent: January 9, 2018
    Assignee: FUJI XEROX CO., LTD.
    Inventors: Fumiaki Mera, Nobuyuki Torigoe, Masaki Hirakata, Hideya Katsuhara, Yoichi Kigoshi, Satomi Kashiwagi, Yuko Iwadate, Kenji Kajiwara, Tatsuki Sano, Takashi Imai, Takeshi Iwanaga
  • Patent number: 9831801
    Abstract: A three-phase inverter system, in one configuration, includes an inverter main circuit and a control circuit. The inverter system includes current sensors which detect output currents in, for example, U- and W-phases, respectively, the inverter main circuit includes a semiconductor switching device with a current sense which is provided in, for example, the V-phase. The control circuit is configured to detect current values from the current sensors inputted thereto and produce driving signals, which drive the upper-arm and lower-arm semiconductor switching devices of the inverter main circuit, based on the detected current values, estimate, based on a detected signal from the semiconductor switching device with the current sense, an output current value in the one of the three series circuits, and detect failure in at least one of the current sensors based on the detected current values from the two current sensors and the estimated output current value.
    Type: Grant
    Filed: August 8, 2016
    Date of Patent: November 28, 2017
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventor: Masaki Hirakata
  • Publication number: 20170269486
    Abstract: An electrophotographic photoreceptor includes an electroconductive substrate, an organic photosensitive layer on the electroconductive substrate and an inorganic protective layer on the organic photosensitive layer, wherein a layer that forms a surface of the organic photosensitive layer contains a charge transporting material, a binder resin, and a silica particle; the inorganic protective layer contains a group 13 element, an oxygen atom, and a hydrogen atom; a sum of element constitution ratios of the group 13 element, the oxygen atom, and the hydrogen atom to all elements constituting the inorganic protective layer is equal to or more than 90 atomic %; and an element composition ratio (oxygen atom/group 13 element) of the oxygen atom and the group 13 element is 1.0 or more and less than 1.5.
    Type: Application
    Filed: July 8, 2016
    Publication date: September 21, 2017
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Fumiaki MERA, Nobuyuki TORIGOE, Masaki HIRAKATA, Hideya KATSUHARA, Yoichi KIGOSHI, Satomi KASHIWAGI, Yuko IWADATE, Kenji KAJIWARA, Tatsuki SANO, Takashi IMAI, Takeshi IWANAGA
  • Publication number: 20170242351
    Abstract: An electrophotographic photoreceptor includes a conductive substrate, an organic photosensitive layer on the conductive substrate, and an inorganic protective layer on the organic photosensitive layer. A layer that constitutes a surface of the organic photosensitive layer contains a charge transport material, a binder resin, silica particles, and a silicone compound.
    Type: Application
    Filed: July 6, 2016
    Publication date: August 24, 2017
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Tatsuki SANO, Hideya KATSUHARA, Masaki HIRAKATA, Takeshi IWANAGA
  • Patent number: 9740115
    Abstract: An electrophotographic photoreceptor includes a conductive substrate, an organic photosensitive layer on the conductive substrate, and an inorganic protective layer on the organic photosensitive layer. A layer that constitutes a surface of the organic photosensitive layer contains a charge transport material, a binder resin, silica particles, and a silicone compound.
    Type: Grant
    Filed: July 6, 2016
    Date of Patent: August 22, 2017
    Assignee: FUJI XEROX CO., LTD.
    Inventors: Tatsuki Sano, Hideya Katsuhara, Masaki Hirakata, Takeshi Iwanaga
  • Publication number: 20170205758
    Abstract: A cleaning member includes a contact portion and a supported portion. The contact portion is in contact with an image carrier provided with a protective layer containing an inorganic material on a front surface thereof. The contact portion has a hardness of rubber equal to or greater than 85 degrees. The supported portion includes the contact portion and is supported so that the contact portion is in contact with the image carrier.
    Type: Application
    Filed: August 25, 2016
    Publication date: July 20, 2017
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Hiroaki AKAMATSU, Masaki HIRAKATA
  • Patent number: 9658544
    Abstract: An electrophotographic photoreceptor includes an electroconductive substrate, a photosensitive layer provided on the electroconductive substrate, and an inorganic surface layer provided on the photosensitive layer, wherein a layer constituting an outermost surface of the photosensitive layer contains from 30% by weight to 70% by weight of silica particles and contains a biphenyl copolymerization type polycarbonate resin including a structural unit represented by the formula (PCA) and a structural unit represented by the formula (PCB) at a copolymerization ratio (PCA:PCB (molar ratio)) of 10:90 to 50:50: wherein, RP1, RP2, RP3, and RP4 each represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 5 to 7 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and XP1 represents a phenylene group, a biphenylene group, a naphthylene group, an alkylene group, or a cycloalkylene group.
    Type: Grant
    Filed: February 19, 2016
    Date of Patent: May 23, 2017
    Assignee: FUJI XEROX CO., LTD.
    Inventors: Hideya Katsuhara, Takashi Imai, Takeshi Iwanaga, Masaki Hirakata, Tatsuki Sano
  • Publication number: 20170090339
    Abstract: A unit for an image forming apparatus includes an electrophotographic photoreceptor that includes a conductive substrate, a photosensitive layer provided on the conductive substrate, and a surface layer provided so as to contact with an outermost surface of the photosensitive layer, and an exposure section that exposes the electrophotographic photoreceptor with a light having a wavelength (?) (nm) so as to form an electrostatic latent image on a charged surface of the electrophotographic photoreceptor, wherein a surface roughness (Rz1) (nm) of the outermost surface of the photosensitive layer satisfies an expression of [(Rz1)?(?)/(4×(n2))] where a refractive index of the surface layer is set as (n2), and an outermost surface of the surface layer has a surface shape different from the outermost surface of the photosensitive layer.
    Type: Application
    Filed: February 4, 2016
    Publication date: March 30, 2017
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Takeshi IWANAGA, Takashi IMAI, Hideya KATSUHARA, Masaki HIRAKATA, Yoichi KIGOSHI, Nobuyuki TORIGOE, Fumiaki MERA
  • Publication number: 20170090310
    Abstract: An electrophotographic photoreceptor includes an electroconductive substrate, a photosensitive layer provided on the electroconductive substrate, and an inorganic surface layer provided on the photosensitive layer, wherein a layer constituting an outermost surface of the photosensitive layer contains from 30% by weight to 70% by weight of silica particles and contains a biphenyl copolymerization type polycarbonate resin including a structural unit represented by the formula (PCA) and a structural unit represented by the formula (PCB) at a copolymerization ratio (PCA:PCB (molar ratio)) of 10:90 to 50:50: wherein, RP1, RP2, RP3, and RP4 each represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 5 to 7 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and XP1 represents a phenylene group, a biphenylene group, a naphthylene group, an alkylene group, or a cycloalkylene group.
    Type: Application
    Filed: February 19, 2016
    Publication date: March 30, 2017
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Hideya KATSUHARA, Takashi IMAI, Takeshi IWANAGA, Masaki HIRAKATA, Tatsuki SANO
  • Publication number: 20170090312
    Abstract: An electrophotographic photosensitive member includes a conductive base; an organic photosensitive layer disposed on the conductive base, the organic photosensitive layer including a layer that constitutes a surface and contains a charge transport material, a binder resin, and silica particles in an amount of about 40% by weight or more; and an inorganic protective layer disposed on the organic photosensitive layer and having a surface roughness Ra of about 5 nm or less.
    Type: Application
    Filed: January 21, 2016
    Publication date: March 30, 2017
    Applicant: FUJI XEROX Co., Ltd.
    Inventors: Masaki HIRAKATA, Hideya KATSUHARA, Yoichi KIGOSHI, Takeshi IWANAGA, Nobuyuki TORIGOE, Takashi IMAI, Tatsuki SANO
  • Publication number: 20170090307
    Abstract: An electrophotographic photosensitive member includes a conductive base; an organic photosensitive layer disposed on the conductive base, the organic photosensitive layer including a layer that constitutes a surface and contains a charge transport material, a binder resin having a viscosity-average molecular weight less than about 50,000, and silica particles in an amount of about 40% by weight or more; and an inorganic protective layer disposed on the organic photosensitive layer.
    Type: Application
    Filed: January 15, 2016
    Publication date: March 30, 2017
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Masaki HIRAKATA, Takeshi IWANAGA, Nobuyuki TORIGOE, Hideya KATSUHARA, Yoichi KIGOSHI, Takashi IMAI, Fumiaki MERA
  • Publication number: 20170077835
    Abstract: A three-phase inverter system, in one configuration, includes an inverter main circuit and a control circuit. The inverter system includes current sensors which detect output currents in, for example, U- and W-phases, respectively, the inverter main circuit includes a semiconductor switching device with a current sense which is provided in, for example, the V-phase. The control circuit is configured to detect current values from the current sensors inputted thereto and produce driving signals, which drive the upper-arm and lower-arm semiconductor switching devices of the inverter main circuit, based on the detected current values, estimate, based on a detected signal from the semiconductor switching device with the current sense, an output current value in the one of the three series circuits, and detect failure in at least one of the current sensors based on the detected current values from the two current sensors and the estimated output current value.
    Type: Application
    Filed: August 8, 2016
    Publication date: March 16, 2017
    Applicant: FUJI ELECTRIC CO., LTD
    Inventor: Masaki HIRAKATA
  • Patent number: 9541886
    Abstract: An image forming apparatus includes an image bearing member having an inorganic protective layer on a surface thereof, a cleaning blade having an inclined surface cut out at a corner portion on a side of the image bearing member, and a support portion that supports the cleaning blade so that the inclined surface is in contact with the image bearing member.
    Type: Grant
    Filed: July 28, 2015
    Date of Patent: January 10, 2017
    Assignee: FUJI XEROX CO., LTD.
    Inventors: Hiroaki Akamatsu, Masaki Hirakata, Tsutomu Sugimoto
  • Publication number: 20160266536
    Abstract: An image forming apparatus includes an image bearing member having an inorganic protective layer on a surface thereof, a cleaning blade having an inclined surface cut out at a corner portion on a side of the image bearing member, and a support portion that supports the cleaning blade so that the inclined surface is in contact with the image bearing member.
    Type: Application
    Filed: July 28, 2015
    Publication date: September 15, 2016
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Hiroaki AKAMATSU, Masaki HIRAKATA, Tsutomu SUGIMOTO
  • Patent number: 9341963
    Abstract: An electrophotographic photoreceptor includes a conductive substrate; an organic photosensitive layer that is provided on the conductive substrate; and an inorganic protective layer that is provided on the organic photosensitive layer so as to be in contact with a surface of the organic photosensitive layer, wherein the organic photosensitive layer includes at least a charge transport material and silica particles in a region on the surface side in contact with the inorganic protective layer.
    Type: Grant
    Filed: September 3, 2013
    Date of Patent: May 17, 2016
    Assignee: FUJI XEROX CO., LTD.
    Inventors: Masaki Hirakata, Hideya Katsuhara, Takeshi Iwanaga, Nobuyuki Torigoe, Takashi Imai, Tomoya Sasaki, Shigeto Hashiba, Kenta Ide