Patents by Inventor Akihiro Kawasaki

Akihiro Kawasaki 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: 10372049
    Abstract: An electrophotographic photoreceptor includes a conductive support and a single-layer photosensitive layer. The conductive support has an outer peripheral surface with a maximum surface roughness height (Rmax) of about 4.0 ?m or less, and the outer peripheral surface has a recess with a depth-to-aperture size ratio (depth/aperture size) of about 0.03 or more and about 0.12 or less. The single-layer photosensitive layer is disposed on the conductive support and has a thickness of about 20 ?m or more and a modulus of elasticity of about 4.5 GPa or more.
    Type: Grant
    Filed: September 8, 2017
    Date of Patent: August 6, 2019
    Assignee: FUJI XEROX CO., LTD.
    Inventors: Akihiro Kawasaki, Hirofumi Nakamura, Yohei Saito, Keisuke Kusano
  • Patent number: 10101678
    Abstract: An electrophotographic photoreceptor includes a conductive substrate and a photosensitive layer disposed on the conductive substrate which serves as an outermost surface of the electrophotographic photoreceptor. The electrophotographic photoreceptor satisfies YC?YA?0.1 MPa, YC?YB?0.1 MPa, and YC?4.5 MPa, where YA, YB, and YC (MPa) represent the Young's moduli of a surface of the photosensitive layer determined by nanoindentation at an indentation depth of 500 nm at end portions A and B extending from a position 10 mm to a position 70 mm from the respective edges of the photosensitive layer toward the center of the photosensitive layer in an axial direction of the electrophotographic photoreceptor and a central portion C extending from a position 20 mm in front of and to a position 20 mm behind the center of the photosensitive layer in the axial direction of the electrophotographic photoreceptor, respectively.
    Type: Grant
    Filed: March 6, 2017
    Date of Patent: October 16, 2018
    Assignee: FUJI XEROX CO., LTD.
    Inventor: Akihiro Kawasaki
  • Publication number: 20180275538
    Abstract: An electrophotographic photoreceptor includes a conductive support and a single-layer photosensitive layer. The conductive support has an outer peripheral surface with a maximum surface roughness height (Rmax) of about 4.0 ?m or less, and the outer peripheral surface has a recess with a depth-to-aperture size ratio (depth/aperture size) of about 0.03 or more and about 0.12 or less. The single-layer photosensitive layer is disposed on the conductive support and has a thickness of about 20 ?m or more and a modulus of elasticity of about 4.5 GPa or more.
    Type: Application
    Filed: September 8, 2017
    Publication date: September 27, 2018
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Akihiro KAWASAKI, Hirofumi NAKAMURA, Yohei SAITO, Keisuke KUSANO
  • Patent number: 10073405
    Abstract: An image forming apparatus includes: an electrophotographic photoreceptor that includes an electroconductive substrate, an undercoat layer which is provided on the electroconductive substrate and has electrostatic capacitance per unit area of from 2.5×10?11 F/cm2 to 2.5×10?10 F/cm2, and a photosensitive layer provided on the undercoat layer; a charging unit; an electrostatic latent image forming unit; a developing unit; an intermediate transfer member; a primary transfer unit that primarily transfers the toner image formed on the surface of the electrophotographic photoreceptor, onto the surface of an intermediate transfer member, while providing a primary transfer current value of from 80 ?A to 160 ?A; and a secondary transfer unit that secondarily transfers the toner image transferred onto the surface of the intermediate transfer member, onto a surface of a recording medium.
    Type: Grant
    Filed: November 22, 2016
    Date of Patent: September 11, 2018
    Assignee: FUJI XEROX CO., LTD.
    Inventors: Akihiro Kawasaki, Hirofumi Nakamura
  • Publication number: 20180081286
    Abstract: An electrophotographic photoreceptor includes a conductive substrate and a photosensitive layer disposed on the conductive substrate which serves as an outermost surface of the electrophotographic photoreceptor. The electrophotographic photoreceptor satisfies YC?YA?0.1 MPa, YC?YB?0.1 MPa, and YC?4.5 MPa, where YA, YB, and YC (MPa) represent the Young's moduli of a surface of the photosensitive layer determined by nanoindentation at an indentation depth of 500 nm at end portions A and B extending from a position 10 mm to a position 70 mm from the respective edges of the photosensitive layer toward the center of the photosensitive layer in an axial direction of the electrophotographic photoreceptor and a central portion C extending from a position 20 mm in front of and to a position 20 mm behind the center of the photosensitive layer in the axial direction of the electrophotographic photoreceptor, respectively.
    Type: Application
    Filed: March 6, 2017
    Publication date: March 22, 2018
    Applicant: FUJI XEROX CO., LTD.
    Inventor: Akihiro KAWASAKI
  • Publication number: 20170351210
    Abstract: An image forming apparatus includes: an electrophotographic photoreceptor that includes an electroconductive substrate, an undercoat layer which is provided on the electroconductive substrate and has electrostatic capacitance per unit area of from 2.5×10?11 F/cm2 to 2.5×10?10 F/cm2, and a photosensitive layer provided on the undercoat layer; a charging unit; an electrostatic latent image forming unit; a developing unit; an intermediate transfer member; a primary transfer unit that primarily transfers the toner image formed on the surface of the electrophotographic photoreceptor, onto the surface of an intermediate transfer member, while providing a primary transfer current value of from 80 ?A to 160 ?A; and a secondary transfer unit that secondarily transfers the toner image transferred onto the surface of the intermediate transfer member, onto a surface of a recording medium.
    Type: Application
    Filed: November 22, 2016
    Publication date: December 7, 2017
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Akihiro KAWASAKI, Hirofumi NAKAMURA
  • Patent number: 8956793
    Abstract: An electrophotographic photoreceptor includes a conductive support, an undercoat layer that is provided on the conductive support and that has a thickness of from 15 ?m to 40 ?m and has light transmittance of 20% or less with respect to light having a wavelength of 450 nm when the thickness is at least 15 ?m, a charge generation layer that is provided on the undercoat layer, and a charge transport layer that is provided on the charge generation layer and that has a thickness of from 15 ?m to 40 ?m and has light transmittance of 30% or less with respect to light having a wavelength of 450 nm when the thickness is at least 15 ?m.
    Type: Grant
    Filed: August 13, 2012
    Date of Patent: February 17, 2015
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Kenta Ide, Kosuke Narita, Akihiro Kawasaki, Satoya Sugiura, Akihiro Nonaka, Hirofumi Nakamura, Kazuhiro Koseki, Shigeto Hashiba
  • Patent number: 8877412
    Abstract: An image forming apparatus includes at least an electrophotographic photoreceptor having at least a conductive support, an undercoat layer, and a photosensitive layer; a charging device that charges the surface of the electrophotographic photoreceptor in a contact charging mode, in which only DC voltage is applied; an electrostatic latent image forming device that exposes the surface of the charged electrophotographic photoreceptor to form an electrostatic latent image; a developing device that develops the electrostatic latent image by a developer to form a toner image; and a transfer device that directly transfers the toner image from the electrophotographic photoreceptor to a transfer medium; and does not include an erasing device for erasing the surface of the electrophotographic photoreceptor after the toner image is transferred onto the transfer medium by the transfer device and before the surface of the electrophotographic photoreceptor is charged by the charging device.
    Type: Grant
    Filed: July 20, 2012
    Date of Patent: November 4, 2014
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Kenta Ide, Kosuke Narita, Hirofumi Nakamura, Kazuhiro Koseki, Akihiro Kawasaki, Shigeto Hashiba, Takahiro Suzuki
  • Patent number: 8808953
    Abstract: An electrophotographic photoreceptor includes a conductive support, and an undercoat layer, a charge generation layer, and a charge transport layer that are provided in this order on the conductive support, wherein the undercoat layer includes at least metallic oxide particles, a reactive acceptor substance including an anthraquinone structure expressed by the following Formula 1, and a binder resin, the charge generation layer includes hydroxygallium phthalocyanine as a charge generation material, and a reflectance of incident light having a wavelength of 780 nm on a surface of the charge generation layer when the charge transport layer is removed is 17% or greater: wherein the anthraquinone structure expressed by Formula 1 is bonded to another structure at a position of *, and thus forms the reactive acceptor substance, and in Formula 1, n1 represents an integer of 1 to 7.
    Type: Grant
    Filed: July 30, 2012
    Date of Patent: August 19, 2014
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Satoya Sugiura, Shigeto Hashiba, Kazuhiro Koseki, Hirofumi Nakamura, Kenta Ide, Akihiro Nonaka, Kosuke Narita, Akihiro Kawasaki
  • Patent number: 8802337
    Abstract: An electrophotographic photoreceptor includes a support; an undercoat layer which is provided on the support and contains at least a binder resin, metal oxide particles, and an electron-accepting compound having an anthraquinone structure, in which a content of the electron-accepting compound is from 0.5% by weight to 1.5% by weight with respect to the metal oxide particles and a contact angle of the metal oxide particles with respect to water is from 7° to 12°; and a photosensitive layer which is provided on the undercoat layer.
    Type: Grant
    Filed: November 8, 2012
    Date of Patent: August 12, 2014
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Akihiro Kawasaki, Shigeto Hashiba, Hirofumi Nakamura, Hidemi Nukada, Satoya Sugiura
  • Publication number: 20130316275
    Abstract: An electrophotographic photoreceptor includes a support; an undercoat layer which is provided on the support and contains at least a binder resin, metal oxide particles, and an electron-accepting compound having an anthraquinone structure, in which a content of the electron-accepting compound is from 0.5% by weight to 1.5% by weight with respect to the metal oxide particles and a contact angle of the metal oxide particles with respect to water is from 7° to 12°; and a photosensitive layer which is provided on the undercoat layer.
    Type: Application
    Filed: November 8, 2012
    Publication date: November 28, 2013
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Akihiro KAWASAKI, Shigeto HASHIBA, Hirofumi NAKAMURA, Hidemi NUKADA, Satoya SUGIURA
  • Publication number: 20130252147
    Abstract: An electrophotographic photoreceptor includes a conductive support, and an undercoat layer, a charge generation layer, and a charge transport layer that are provided in this order on the conductive support, wherein the undercoat layer includes at least metallic oxide particles, a reactive acceptor substance including an anthraquinone structure expressed by the following Formula 1, and a binder resin, the charge generation layer includes hydroxygallium phthalocyanine as a charge generation material, and a reflectance of incident light having a wavelength of 780 nm on a surface of the charge generation layer when the charge transport layer is removed is 17% or greater: wherein the anthraquinone structure expressed by Formula 1 is bonded to another structure at a position of *, and thus forms the reactive acceptor substance, and in Formula 1, n1 represents an integer of 1 to 7.
    Type: Application
    Filed: July 30, 2012
    Publication date: September 26, 2013
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Satoya SUGIURA, Shigeto HASHIBA, Kazuhiro KOSEKI, Hirofumi NAKAMURA, Kenta IDE, Akihiro NONAKA, Kosuke NARITA, Akihiro KAWASAKI
  • Publication number: 20130236821
    Abstract: An electrophotographic photoreceptor includes a conductive support, an undercoat layer that is provided on the conductive support and that has a thickness of from 15 ?m to 40 ?m and has light transmittance of 20% or less with respect to light having a wavelength of 450 nm when the thickness is at least 15 ?m, a charge generation layer that is provided on the undercoat layer, and a charge transport layer that is provided on the charge generation layer and that has a thickness of from 15 ?m to 40 ?m and has light transmittance of 30% or less with respect to light having a wavelength of 450 nm when the thickness is at least 15 ?m.
    Type: Application
    Filed: August 13, 2012
    Publication date: September 12, 2013
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Kenta IDE, Kosuke NARITA, Akihiro KAWASAKI, Satoya SUGIURA, Akihiro NONAKA, Hirofumi NAKAMURA, Kazuhiro KOSEKI, Shigeto HASHIBA
  • Publication number: 20130236820
    Abstract: An image forming apparatus includes at least an electrophotographic photoreceptor having at least a conductive support, an undercoat layer, and a photosensitive layer; a charging device that charges the surface of the electrophotographic photoreceptor in a contact charging mode, in which only DC voltage is applied; an electrostatic latent image forming device that exposes the surface of the charged electrophotographic photoreceptor to form an electrostatic latent image; a developing device that develops the electrostatic latent image by a developer to form a toner image; and a transfer device that directly transfers the toner image from the electrophotographic photoreceptor to a transfer medium; and does not include an erasing device for erasing the surface of the electrophotographic photoreceptor after the toner image is transferred onto the transfer medium by the transfer device and before the surface of the electrophotographic photoreceptor is charged by the charging device.
    Type: Application
    Filed: July 20, 2012
    Publication date: September 12, 2013
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Kenta IDE, Kosuke NARITA, Hirofumi NAKAMURA, Kazuhiro KOSEKI, Akihiro KAWASAKI, Shigeto HASHIBA, Takahiro SUZUKI
  • Patent number: 8041241
    Abstract: In a disclosed image forming apparatus, a developing bias applied to a developer carrier or exposure energy with which an image carrier is exposed is adjusted such that an isolated one-dot image on the image carrier has a predetermined image density. When the image carrier is exposed to form dot images continuously arranged in a main scanning direction, the exposure time period for each dot image is shorter than that when the image carrier is exposed to form the isolated one-dot image.
    Type: Grant
    Filed: January 22, 2008
    Date of Patent: October 18, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Akihiro Kawasaki, Yoshiko Ogawa, Rumi Konishi
  • Patent number: 7885566
    Abstract: A toner consumption-calculating apparatus includes a printed portion area-detecting unit that detects an area of a printed portion of image data of a latent image that is formed on a latent image-bearing member; a latent image portion area-detecting unit that detects an area of a latent image portion on the latent image-bearing member; and a latent image portion toner consumption-calculating unit that calculates latent image portion toner consumption that indicates toner amount that is consumed due to adhering on the latent image portion. The latent image portion toner consumption-calculating unit uses a detection result of the latent image portion area-detecting unit and a detection result of the printed portion area-detecting unit to calculate the latent image portion toner consumption.
    Type: Grant
    Filed: September 12, 2007
    Date of Patent: February 8, 2011
    Assignee: Ricoh Company, Limited
    Inventors: Rumi Konishi, Kenichi Ono, Akihiro Kawasaki, Yoshiko Ogawa, Atsushi Takehara
  • Patent number: 7791635
    Abstract: In a disclosed image forming apparatus, a developing bias applied to a developer carrier or exposure energy with which an image carrier is exposed is adjusted such that an isolated one-dot image on the image carrier has a predetermined image density. When the image carrier is exposed to form dot images continuously arranged in a sub scanning direction, the exposure time period for each dot image is shorter than a time period for exposing the image carrier to form the isolated one-dot image.
    Type: Grant
    Filed: December 22, 2008
    Date of Patent: September 7, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshiko Ogawa, Akihiro Kawasaki
  • Patent number: 7734235
    Abstract: In an image forming apparatus, an intermediate transfer belt is made of a resin film and is supported by a plurality of rollers. A driving roller that is one of the plurality of rollers, drives the intermediate transfer belt, and also functions as an opposing unit with respect to a secondary transfer roller. The driving roller is made of metal, and applies a bias to at least secondary transfer units, at least at a time of performing primary transfer to a plurality of image bearing bodies.
    Type: Grant
    Filed: March 9, 2006
    Date of Patent: June 8, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Atsushi Takehara, Akihiro Kawasaki, Yoshie Iwakura, Tomoya Adachi, Takafumi Miyazaki
  • Patent number: 7636539
    Abstract: An image forming unit includes four photoconductors, a belt extended around a driving roller and an extension-cum-primary transfer roller. Three primary transfer rollers sandwich the belt in association with a corresponding photoconductor. The extension-cum-primary transfer roller serves both as an extension roller and a primary transfer roller.
    Type: Grant
    Filed: April 26, 2006
    Date of Patent: December 22, 2009
    Assignee: Ricoh Company Limited
    Inventors: Akihiro Kawasaki, Atsushi Takehara, Yoshie Iwakura, Takafumi Miyazaki, Tomoya Adachi
  • Publication number: 20090176171
    Abstract: In a disclosed image forming apparatus, a developing bias applied to a developer carrier or exposure energy with which an image carrier is exposed is adjusted such that an isolated one-dot image on the image carrier has a predetermined image density. When the image carrier is exposed to form dot images continuously arranged in a sub scanning direction, the exposure time period for each dot image is shorter than a time period for exposing the image carrier to form the isolated one-dot image.
    Type: Application
    Filed: December 22, 2008
    Publication date: July 9, 2009
    Inventors: Yoshiko OGAWA, Akihiro Kawasaki