Patents by Inventor Hiroko Yokoyama

Hiroko Yokoyama 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).

  • Publication number: 20240094661
    Abstract: An image forming apparatus includes a rotatable image bearing member and a rotatable developing member to carry developer made up of toner particles and carrier particles adhered to surfaces of the toner particles. Where a pressing force pressing the developing member against the image bearing member is F1, a total number of the carrier particles interposed between the toner particles and the image bearing member is N1, and an adhesion Ft between a carrier particle and a toner particle, measured when the carrier particle is pressed against the toner particle with F1/N1 that is a pressing force per unit carrier particle, and an adhesion Fdr1 between the carrier particle and the image bearing member, measured when the carrier particle is pressed against the image bearing member with F1/N1, satisfy Ft?Fdr1.
    Type: Application
    Filed: November 9, 2023
    Publication date: March 21, 2024
    Inventors: Shuichi Tetsuno, Shinji Katagiri, Koji An, Hiroko Yokoyama, Wataru Takahashi, Shohei Ishio, Takayuki Tanaka, Tomonori Matsunaga
  • Patent number: 11846899
    Abstract: An image forming apparatus includes a rotatable image bearing member and a rotatable developing member to carry developer made up of toner particles and carrier particles adhered to surfaces of the toner particles. Where a pressing force pressing the developing member against the image bearing member is F1, a total number of the carrier particles interposed between the toner particles and the image bearing member is N1, and an adhesion Ft between a carrier particle and a toner particle, measured when the carrier particle is pressed against the toner particle with F1/N1 that is a pressing force per unit carrier particle, and an adhesion Fdr1 between the carrier particle and the image bearing member, measured when the carrier particle is pressed against the image bearing member with F1/N1, satisfy Ft?Fdr1.
    Type: Grant
    Filed: July 27, 2021
    Date of Patent: December 19, 2023
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shuichi Tetsuno, Shinji Katagiri, Koji An, Hiroko Yokoyama, Wataru Takahashi, Shohei Ishio, Takayuki Tanaka, Tomonori Matsunaga
  • Patent number: 11460795
    Abstract: An image forming apparatus includes an image bearing member, an exposure unit, a developing member, and a control unit. The exposure unit exposes a surface of the image bearing member to light to form an electrostatic latent image. The developing member develops the electrostatic latent image by using toner to form a toner image. In image formation based on input image data, the control unit uses the exposure unit to control a maximum gradation value of the toner image to be formed on the image bearing member surface, based on a repetition length of a dither pattern. The control unit performs control so that the maximum gradation value is larger in a case where a first dither pattern having a first length as the repetition length is used than where a second dither pattern having a second length longer than the first length as the repetition length is used.
    Type: Grant
    Filed: August 10, 2021
    Date of Patent: October 4, 2022
    Assignee: Canon Kabushiki Kaisha
    Inventors: Keisuke Ishizumi, Hiroko Yokoyama, Shinji Katagiri
  • Publication number: 20220290337
    Abstract: The present invention provides a method for producing a carbon fiber bundle, the method including steps (b) to (e) described below: (b) an oil agent application step of applying a silicone oil agent to a precursor fiber bundle to produce an oil-agent-attached precursor fiber bundle; (d) a stabilization step of subjecting the oil-agent-attached precursor fiber bundle to an oxidization treatment to produce an oxidized fiber bundle; and (e) a carbonization step of carbonizing the oxidized fiber bundle, wherein the silicone oil agent has a skin over time at 250° C. of less than 40 minutes.
    Type: Application
    Filed: August 27, 2020
    Publication date: September 15, 2022
    Applicants: TEIJIN LIMITED, WACKER CHEMIE AG
    Inventors: Hiroko YOKOYAMA, Eiji KINOSHITA, Satoshi OHNO, Izuru TAKETA
  • Publication number: 20220066372
    Abstract: An image forming apparatus includes an image bearing member, an exposure unit, a developing member, and a control unit. The exposure unit exposes a surface of the image bearing member to light to form an electrostatic latent image. The developing member develops the electrostatic latent image by using toner to form a toner image. In image formation based on input image data, the control unit uses the exposure unit to control a maximum gradation value of the toner image to be formed on the image bearing member surface, based on a repetition length of a dither pattern. The control unit performs control so that the maximum gradation value is larger in a case where a first dither pattern having a first length as the repetition length is used than where a second dither pattern having a second length longer than the first length as the repetition length is used.
    Type: Application
    Filed: August 10, 2021
    Publication date: March 3, 2022
    Inventors: Keisuke Ishizumi, Hiroko Yokoyama, Shinji Katagiri
  • Publication number: 20220035274
    Abstract: An image forming apparatus includes a rotatable image bearing member and a rotatable developing member to carry developer made up of toner particles and carrier particles adhered to surfaces of the toner particles. Where a pressing force pressing the developing member against the image bearing member is F1, a total number of the carrier particles interposed between the toner particles and the image bearing member is N1, and an adhesion Ft between a carrier particle and a toner particle, measured when the carrier particle is pressed against the toner particle with F1/N1 that is a pressing force per unit carrier particle, and an adhesion Fdr1 between the carrier particle and the image bearing member, measured when the carrier particle is pressed against the image bearing member with F1/N1, satisfy Ft?Fdr1.
    Type: Application
    Filed: July 27, 2021
    Publication date: February 3, 2022
    Inventors: Shuichi Tetsuno, Shinji Katagiri, Koji An, Hiroko Yokoyama, Wataru Takahashi, Shohei Ishio, Takayuki Tanaka, Tomonori Matsunaga
  • Patent number: D515054
    Type: Grant
    Filed: November 13, 2003
    Date of Patent: February 14, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Ryoichi Ishiura, Hiroko Yokoyama, Hiroko Nakano, Taihei Miyaji
  • Patent number: D520193
    Type: Grant
    Filed: May 4, 2005
    Date of Patent: May 2, 2006
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Consumer Marketing Corporation
    Inventor: Hiroko Yokoyama
  • Patent number: D454332
    Type: Grant
    Filed: April 19, 2001
    Date of Patent: March 12, 2002
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Hiroko Yokoyama
  • Patent number: D454852
    Type: Grant
    Filed: July 17, 2001
    Date of Patent: March 26, 2002
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Hiroko Yokoyama
  • Patent number: D468281
    Type: Grant
    Filed: May 10, 2002
    Date of Patent: January 7, 2003
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hikari Taniguchi, Hiroko Yokoyama
  • Patent number: D476968
    Type: Grant
    Filed: July 24, 2002
    Date of Patent: July 8, 2003
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Hiroko Yokoyama
  • Patent number: D479215
    Type: Grant
    Filed: June 20, 2002
    Date of Patent: September 2, 2003
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Hiroko Yokoyama
  • Patent number: D479234
    Type: Grant
    Filed: July 25, 2002
    Date of Patent: September 2, 2003
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Keita Tanaka, Noriaki Baba, Hiroko Yokoyama
  • Patent number: D479235
    Type: Grant
    Filed: July 25, 2002
    Date of Patent: September 2, 2003
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Keita Tanaka, Noriaki Baba, Hiroko Yokoyama
  • Patent number: D744481
    Type: Grant
    Filed: May 9, 2014
    Date of Patent: December 1, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Hiroko Yokoyama
  • Patent number: D753103
    Type: Grant
    Filed: May 9, 2014
    Date of Patent: April 5, 2016
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Hiroko Yokoyama