Patents by Inventor Hideaki Yasunaga

Hideaki Yasunaga 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: 10001731
    Abstract: A composition for seamless belt includes a thermoplastic resin; and a conductive agent. A liquid extracted from the composition with methanol has an intensity not greater than 7×108 in a total ion chromatogram.
    Type: Grant
    Filed: December 4, 2015
    Date of Patent: June 19, 2018
    Assignee: RICOH COMPANY, LTD.
    Inventors: Makoto Matsushita, Akira Izutani, Hideaki Yasunaga, Keiichiro Juri, Ayano Momose, Yuri Haga, Hiroaki Takahashi
  • Patent number: 9983505
    Abstract: Provided is a developing roller including a shaft body, an elastic layer formed on an external circumference of the shaft body, and a surface layer formed on an external circumference of the elastic layer. The surface layer is formed of polyurethane containing a reaction product of a fluoroethylene vinyl ether copolymer and an isocyanurate form of isocyanate and having a film thickness of from 0.5 ?m through 2.0 ?m. The developing roller has grooves in a surface of the developing roller. The angle of the grooves from a circumferential direction is from 0 degrees through 30 degrees.
    Type: Grant
    Filed: April 20, 2017
    Date of Patent: May 29, 2018
    Assignee: RICOH COMPANY, LTD.
    Inventors: Hideaki Yasunaga, Keiichiro Juri
  • Patent number: 9921526
    Abstract: A semiconductive resin composition includes at least two thermoplastic resins and a conductive filler. Each of the two thermoplastic resins has a sea-island structure, and 40% to 75% of the conductive filler are present in the thermoplastic resin in an island portion of the sea-island structure at an areal ratio of a cross section observed with a scanning electron microscope.
    Type: Grant
    Filed: December 14, 2015
    Date of Patent: March 20, 2018
    Assignee: RICOH COMPANY, LTD.
    Inventors: Hiroaki Takahashi, Hideaki Yasunaga, Akira Izutani, Makoto Matsushita, Keiichiro Juri, Yuri Haga, Ayano Momose
  • Patent number: 9891558
    Abstract: A semiconductive resin composition includes a plurality of thermoplastic resins forming a sea-island structure including a sea portion and an island portion; and a plurality of conductive fillers. The sea portion includes at least two of the thermoplastic resins, at least one of the at least two of the thermoplastic resins is a copolymer, and the content of the copolymer is from 20% to 60% by weight per 100% by weight of the thermoplastic resins in the sea portion, and the following relation is satisfied: 1.5?B/A?10 wherein A represents an average primary particle diameter of one of the conductive fillers having the smallest average primary particle diameter and B represents an average primary particle diameter of one of the conductive fillers having the largest average primary particle diameter.
    Type: Grant
    Filed: December 18, 2015
    Date of Patent: February 13, 2018
    Assignee: RICOH COMPANY, LTD.
    Inventors: Makoto Matsushita, Akira Izutani, Hiroaki Takahashi, Yuri Haga, Keiichiro Juri, Hideaki Yasunaga
  • Patent number: 9851656
    Abstract: A developing roller includes a conductive axis body; a conductive elastic layer overlying the conductive axis body; and a toner bearing layer overlying the conductive elastic layer and having a surface dispersed with particles having an average particle diameter of from 11 nm to 40 nm. The rotary torque is from 2.5 N to 3.5 N.
    Type: Grant
    Filed: March 17, 2016
    Date of Patent: December 26, 2017
    Assignee: RICOH COMPANY, LTD.
    Inventors: Keiichiro Juri, Makoto Matsushita, Hideaki Yasunaga
  • Patent number: 9778602
    Abstract: An image forming apparatus includes at least an image bearer; an electrostatic latent image former to form an electrostatic latent image on the image bearer; an image developer to develop the electrostatic latent image with a toner to from a toner image; a first transferer to transfer the toner image from the image bearer onto an intermediate transfer belt; and a cleaner including a cleaning blade having a Martens hardness of from 0.8 to 10.0 N/m2, to clean the intermediate transfer belt while contacting the surface of the intermediate transfer belt. The intermediate transfer belt includes a thermoplastic resin and a conductive resin, and has a surface concentration of oxygen atoms derived from the conductive resin, measured by XPS, of from 1.0% to 3.0% by atom.
    Type: Grant
    Filed: March 18, 2016
    Date of Patent: October 3, 2017
    Assignee: RICOH COMPANY, LTD.
    Inventors: Keiichiro Juri, Hideaki Yasunaga, Akira Izutani, Makoto Matsushita, Hiroaki Takahashi, Ayano Momose, Yuri Haga
  • Publication number: 20170219954
    Abstract: Provided is a developing roller including a shaft body, an elastic layer formed on an external circumference of the shaft body, and a surface layer formed on an external circumference of the elastic layer. The surface layer is formed of polyurethane containing a reaction product of a fluoroethylene vinyl ether copolymer and an isocyanurate form of isocyanate and having a film thickness of from 0.5 ?m through 2.0 ?m. The developing roller has grooves in a surface of the developing roller. The angle of the grooves from a circumferential direction is from 0 degrees through 30 degrees.
    Type: Application
    Filed: April 20, 2017
    Publication date: August 3, 2017
    Applicant: RICOH COMPANY, LTD.
    Inventors: Hideaki YASUNAGA, Keiichiro JURI
  • Patent number: 9720354
    Abstract: An intermediate transfer belt for use in electrophotography is provided. The intermediate transfer belt includes a thermoplastic resin having a vinylidene difluoride (VdF) structure. The intermediate transfer belt has a degree of crystallinity in the range of 17% to 39%.
    Type: Grant
    Filed: June 5, 2015
    Date of Patent: August 1, 2017
    Assignee: RICOH COMPANY, LTD.
    Inventors: Keiichiro Juri, Hideaki Yasunaga, Akira Izutani, Makoto Matsushita, Ayano Momose
  • Patent number: 9625858
    Abstract: An intermediate transfer belt includes a thermoplastic resin and a fibrous material. The fibrous material has an orientation angle Fa of from 5° to 30° in a direction perpendicular to a circumferential direction of the intermediate transfer belt.
    Type: Grant
    Filed: February 22, 2016
    Date of Patent: April 18, 2017
    Assignee: RICOH COMPANY, LTD.
    Inventors: Akira Izutani, Hideaki Yasunaga, Makoto Matsushita, Hiroaki Takahashi, Keiichiro Juri, Ayano Momose, Yuri Haga
  • Publication number: 20160274500
    Abstract: An image forming apparatus includes at least an image bearer; an electrostatic latent image former to form an electrostatic latent image on the image bearer; an image developer to develop the electrostatic latent image with a toner to from a toner image; a first transferer to transfer the toner image from the image bearer onto an intermediate transfer belt; and a cleaner including a cleaning blade having a Martens hardness of from 0.8 to 10.0 N/m2, to clean the intermediate transfer belt while contacting the surface of the intermediate transfer belt. The intermediate transfer belt includes a thermoplastic resin and a conductive resin, and has a surface concentration of oxygen atoms derived from the conductive resin, measured by XPS, of from 1.0% to 3.0% by atom.
    Type: Application
    Filed: March 18, 2016
    Publication date: September 22, 2016
    Applicant: RICOH COMPANY, LTD.
    Inventors: Keiichiro JURI, Hideaki YASUNAGA, Akira IZUTANI, Makoto MATSUSHITA, Hiroaki TAKAHASHI, Ayano MOMOSE, Yuri HAGA
  • Publication number: 20160274489
    Abstract: A developing roller includes a conductive axis body; a conductive elastic layer overlying the conductive axis body; and a toner bearing layer overlying the conductive elastic layer and having a surface dispersed with particles having an average particle diameter of from 11 nm to 40 nm. The rotary torque is from 2.5 N to 3.5 N.
    Type: Application
    Filed: March 17, 2016
    Publication date: September 22, 2016
    Applicant: RICOH COMPANY, LTD.
    Inventors: Keiichiro JURI, Makoto MATSUSHITA, Hideaki YASUNAGA
  • Publication number: 20160259273
    Abstract: An intermediate transfer belt includes a thermoplastic resin and a fibrous material. The fibrous material has an orientation angle Fa of from 5° to 30° in a direction perpendicular to a circumferential direction of the intermediate transfer belt.
    Type: Application
    Filed: February 22, 2016
    Publication date: September 8, 2016
    Applicant: RICOH COMPANY, LTD.
    Inventors: Akira Izutani, Hideaki Yasunaga, Makoto Matsushita, Hiroaki Takahashi, Keiichiro Juri, Ayano Momose, Yuri Haga
  • Publication number: 20160202638
    Abstract: A semiconductive resin composition includes at least two thermoplastic resins and a conductive filler. Each of the two thermoplastic resins has a sea-island structure, and 40% to 75% of the conductive filler are present in the thermoplastic resin in an island portion of the sea-island structure at an areal ratio of a cross section observed with a scanning electron microscope.
    Type: Application
    Filed: December 14, 2015
    Publication date: July 14, 2016
    Applicant: Ricoh Company, Ltd.
    Inventors: Hiroaki Takahashi, Hideaki Yasunaga, Akira Izutani, Makoto Matsushita, Keiichiro Juri, Yuri Haga, Ayano Momose
  • Publication number: 20160202639
    Abstract: A semiconductive resin composition includes a plurality of thermoplastic resins forming a sea-island structure including a sea portion and an island portion; and a plurality of conductive fillers. The sea portion includes at least two of the thermoplastic resins, at least one of the at least two of the thermoplastic resins is a copolymer, and the content of the copolymer is from 20% to 60% by weight per 100% by weight of the thermoplastic resins in the sea portion, and the following relation is satisfied: 1.5?B/A?10 wherein A represents an average primary particle diameter of one of the conductive fillers having the smallest average primary particle diameter and B represents an average primary particle diameter of one of the conductive fillers having the largest average primary particle diameter.
    Type: Application
    Filed: December 18, 2015
    Publication date: July 14, 2016
    Applicant: RICOH COMPANY, LTD.
    Inventors: Makoto Matsushita, Akira IZUTANI, Hiroaki TAKAHASHI, Yuri HAGA, Keiichiro JURI, Hideaki YASUNAGA
  • Publication number: 20160187816
    Abstract: A composition for seamless belt includes a thermoplastic resin; and a conductive agent. A liquid extracted from the composition with methanol has an intensity not greater than 7×108 in a total ion chromatogram.
    Type: Application
    Filed: December 4, 2015
    Publication date: June 30, 2016
    Applicant: RICOH COMPANY, LTD.
    Inventors: Makoto Matsushita, Akira IZUTANI, Hideaki YASUNAGA, Keiichiro JURI, Ayano MOMOSE, Yuri HAGA, Hiroaki TAKAHASHI
  • Publication number: 20160004191
    Abstract: An intermediate transfer belt for use in electrophotography is provided. The intermediate transfer belt includes a thermoplastic resin having a vinylidene difluoride (VdF) structure. The intermediate transfer belt has a degree of crystallinity in the range of 17% to 39%.
    Type: Application
    Filed: June 5, 2015
    Publication date: January 7, 2016
    Applicant: RICOH COMPANY, LTD.
    Inventors: Keiichiro Juri, Hideaki Yasunaga, Akira lzutani, Makoto Matsushita, Ayano Momose
  • Patent number: 9122204
    Abstract: A developing device includes a developing roller including a base and a surface layer formed on the base, the surface layer including a polyurethane resin having a fluorine group and a polyfunctional isocyanurate structure, a toner storage chamber being partially in contact with the developing roller and to support the developing roller, and a sealing member provided at opposed ends of an end portion of the toner storage chamber in a rotating axis direction of the developing roller, and to seal in toner moving to the end portion of the toner storage chamber, the sealing member before use having a coefficient of static friction in a range of from 0.08 to 0.19.
    Type: Grant
    Filed: September 2, 2014
    Date of Patent: September 1, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Keiichiro Juri, Hideaki Yasunaga
  • Patent number: 9098013
    Abstract: A developing roller, including: a shaft containing a metal; an elastic layer on a circumference of the shaft; and a surface layer on a circumferential surface of the elastic layer, wherein the surface layer contains: a polyurethane which is a reaction product between a fluoroethylene vinyl ether copolymer and an isocyanurate form of an isocyanate; and particles having an average primary particle diameter of 5 nm to 30 nm, and wherein the polyurethane has a peak intensity ratio of a NCO group to a hydroxyl group of 5.6 to 8.8 in an infrared absorption spectrum obtained by an attenuated total reflection method.
    Type: Grant
    Filed: April 23, 2014
    Date of Patent: August 4, 2015
    Assignee: RICOH COMPANY, LTD.
    Inventors: Hideaki Yasunaga, Keiichiro Juri, Yuta Takeuchi, Tsuyoshi Nozaki, Yoshimichi Ishikawa, Tomoharu Miki
  • Patent number: 9031478
    Abstract: A developing roller includes a core metal and an elastic layer formed on an outer circumference of the core metal. An outermost surface of the developing roller is roughened. A difference between a maximum value and a minimum value of an indentation power of the outermost surface is 10% to 21%, wherein the indentation power is measured by a micro-indentation test at 120 locations spaced 3 degrees apart on a circumference of the developing roller, which is at a center of the developing roller with respect to a longitudinal direction. A developing device and an image forming apparatus each include the developing roller.
    Type: Grant
    Filed: August 30, 2012
    Date of Patent: May 12, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Keiichiro Juri, Hideaki Yasunaga
  • Patent number: 9026015
    Abstract: A developing roller to bear toner thereon is provided. The developing roller includes a cylindrical electroconductive substrate; an electroconductive elastic layer located on a peripheral surface of the cylindrical electroconductive substrate; and a toner bearing layer located on a peripheral surface of the electroconductive elastic layer. The toner bearing layer includes a polyurethane resin, which is a reaction product of at least an isocyanate compound having an isocyanurate structure and a polyol at a NCO/OH molar ratio of from 90 to 110. The toner bearing layer has a water contact angle of from 135° to 155°, and a static friction coefficient of from 0.10 to 0.15.
    Type: Grant
    Filed: January 22, 2014
    Date of Patent: May 5, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Keiichiro Juri, Hideaki Yasunaga, Chiyoshi Nozaki