Patents by Inventor Kenichi Kaku

Kenichi Kaku 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: 20210116826
    Abstract: A process cartridge which allows any spot and stripe as image defects to be suppressed is provided. A process cartridge, in which an electroconductive layer of a charging member has a matrix including a first rubber, and domains dispersed in the matrix, the domains include a second rubber and an electron electroconductive agent, at least some of the domains are exposed on a surface of the charging member, when a volume resistivity of the matrix is 105 times or more a volume resistivity of the domains, a protective layer of an electrophotographic photosensitive member includes a metal oxide particle, and when a number average primary particle size of the metal oxide particle is defined as Sm and an average value of equivalent circle diameters of the domains is defined as Sd, the Sd/Sm satisfies the following expression (1): 0.5<Sd/Sm<100 . . . expression (1).
    Type: Application
    Filed: October 14, 2020
    Publication date: April 22, 2021
    Inventors: Tsutomu Nishida, Yuka Ishiduka, Kenichi Kaku, Nobuhiro Nakamura, Hiroyuki Watanabe, Hideharu Shimozawa, Atsushi Okuda, Yuichi Kikuchi, Kazuhiro Yamauchi
  • Patent number: 10831118
    Abstract: A method for producing an electrophotographic photosensitive member having a photosensitive layer and a protective layer above a support in this order includes: forming a coating film for a protective layer by coating a coating liquid for the protective layer for forming the protective layer on the photosensitive layer and curing the coating film for the protective layer, in which the coating liquid for the protective layer contains a solvent, a compound represented by a general formula (1), a compound represented by a general formula (2), and a compound represented by a general formula (3) at a specific ratio. In addition, in an electrophotographic photosensitive member having a photosensitive layer and a protective layer above a support in this order, the protective layer is obtained by curing a coating liquid for the protective layer.
    Type: Grant
    Filed: May 28, 2019
    Date of Patent: November 10, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Hiroyuki Watanabe, Tsutomu Nishida, Yuka Ishiduka, Atsushi Okuda, Hideharu Shimozawa, Nobuhiro Nakamura, Koichi Nakata, Haruki Mori, Kenichi Kaku
  • Publication number: 20200264526
    Abstract: The present disclosure provides an electrophotographic photosensitive member that suppresses electric potential fluctuations in repeated use. The electrophotographic photosensitive member includes a support, a photosensitive layer and a protective layer, in this order, wherein the photosensitive layer includes a compound having a structure represented by formula (1), and the protective layer includes a resin having a structure represented by formula (2) and a structure represented by formula (3).
    Type: Application
    Filed: February 10, 2020
    Publication date: August 20, 2020
    Inventors: Hideharu Shimozawa, Tsutomu Nishida, Atsushi Okuda, Yuka Ishiduka, Kenichi Kaku, Nobuhiro Nakamura, Hiroyuki Watanabe
  • Patent number: 10558132
    Abstract: An electrophotographic photosensitive member includes a support and a surface layer, in which the surface layer contains a copolymer of a composition which contains at least a compound represented by the following general formula (1) and a compound represented by the following general formula (2), a content of the compound represented by the general formula (1) in the composition is 25 mass % or more and 70 mass % or less with respect to a total content of the compound represented by the general formula (1) and the compound represented by the general formula (2), and the total content of the compound represented by the general formula (1) and the compound represented by the general formula (2) is 55 mass % or more with respect to a total mass of the composition.
    Type: Grant
    Filed: May 28, 2019
    Date of Patent: February 11, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yuka Ishiduka, Tsutomu Nishida, Atsushi Okuda, Hiroyuki Watanabe, Hideharu Shimozawa, Nobuhiro Nakamura, Kenichi Kaku, Daisuke Miura, Koichi Nakata, Masaki Nonaka, Koji Takahashi, Haruki Mori
  • Patent number: 10558133
    Abstract: An electrophotographic photosensitive member suppressing potential variation due to repeated use is provided. The electrophotographic photosensitive member is an electrophotographic photosensitive member including a support, a photosensitive layer and a protective layer in this order, wherein the protective layer contains: a resin including a structure represented by a general formula (1) and a structure represented by a general formula (2); and a compound represented by a general formula (3), the molar ratio of the proportion of the structure represented by the general formula (2) to the proportion of the structure represented by the general formula (1) in the resin is 0.0002 to 0.1000 in a molar ratio, and the molar ratio of the content of the compound represented by the general formula (3) to the content of the structure represented by the general formula (1) in the resin in the protective layer is 0.0002 to 0.1000 in a molar ratio.
    Type: Grant
    Filed: May 28, 2019
    Date of Patent: February 11, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Nobuhiro Nakamura, Tsutomu Nishida, Atsushi Okuda, Yuka Ishiduka, Hiroyuki Watanabe, Hideharu Shimozawa, Kenichi Kaku, Koichi Nakata, Haruki Mori
  • Patent number: 10539892
    Abstract: Provided is an electrophotographic photosensitive member that is reduced in exposure memory and is excellent in electrical characteristics and durability. The electrophotographic photosensitive member includes in this order: a support; a photosensitive layer; and a protective layer, wherein the protective layer contains a resin having a structure represented by the following general formula (1) and a structure represented by the following general formula (2).
    Type: Grant
    Filed: May 28, 2019
    Date of Patent: January 21, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Tsutomu Nishida, Yuka Ishiduka, Kenichi Kaku, Nobuhiro Nakamura, Hiroyuki Watanabe, Hideharu Shimozawa, Atsushi Okuda
  • Patent number: 10539888
    Abstract: An electrophotographic photosensitive member includes an electroconductive support member and a photosensitive layer. The uppermost layer of the electrophotographic photosensitive member defines a surface layer, and the surface layer contains polytetrafluoroethylene particles, a charge transporting material, and polyvinyl acetal. The proportion of the polyvinyl acetal content to the polytetrafluoroethylene particles content in the surface layer is in the range of 0.1% by mass to 15.0% by mass, and the charge transporting material content in the surface layer is 35% by mass or more relative to the total mass of the surface layer.
    Type: Grant
    Filed: June 13, 2018
    Date of Patent: January 21, 2020
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kenichi Kaku, Kaname Watariguchi, Kazuko Araki, Tomohito Ishida, Michiyo Sekiya
  • Publication number: 20190369516
    Abstract: An electrophotographic photosensitive member suppressing potential variation due to repeated use is provided. The electrophotographic photosensitive member is an electrophotographic photosensitive member including a support, a photosensitive layer and a protective layer in this order, wherein the protective layer contains: a resin including a structure represented by a general formula (1) and a structure represented by a general formula (2); and a compound represented by a general formula (3), the molar ratio of the proportion of the structure represented by the general formula (2) to the proportion of the structure represented by the general formula (1) in the resin is 0.0002 to 0.1000 in a molar ratio, and the molar ratio of the content of the compound represented by the general formula (3) to the content of the structure represented by the general formula (1) in the resin in the protective layer is 0.0002 to 0.1000 in a molar ratio.
    Type: Application
    Filed: May 28, 2019
    Publication date: December 5, 2019
    Inventors: Nobuhiro Nakamura, Tsutomu Nishida, Atsushi Okuda, Yuka Ishiduka, Hiroyuki Watanabe, Hideharu Shimozawa, Kenichi Kaku, Koichi Nakata, Haruki Mori
  • Publication number: 20190369515
    Abstract: Provided is an electrophotographic photosensitive member that is reduced in exposure memory and is excellent in electrical characteristics and durability. The electrophotographic photosensitive member includes in this order: a support; a photosensitive layer; and a protective layer, wherein the protective layer contains a resin having a structure represented by the following general formula (1) and a structure represented by the following general formula (2).
    Type: Application
    Filed: May 28, 2019
    Publication date: December 5, 2019
    Inventors: Tsutomu Nishida, Yuka Ishiduka, Kenichi Kaku, Nobuhiro Nakamura, Hiroyuki Watanabe, Hideharu Shimozawa, Atsushi Okuda
  • Publication number: 20190369511
    Abstract: An electrophotographic photosensitive member includes a support and a surface layer, in which the surface layer contains a copolymer of a composition which contains at least a compound represented by the following general formula (1) and a compound represented by the following general formula (2), a content of the compound represented by the general formula (1) in the composition is 25 mass % or more and 70 mass % or less with respect to a total content of the compound represented by the general formula (1) and the compound represented by the general formula (2), and the total content of the compound represented by the general formula (1) and the compound represented by the general formula (2) is 55 mass % or more with respect to a total mass of the composition.
    Type: Application
    Filed: May 28, 2019
    Publication date: December 5, 2019
    Inventors: Yuka Ishiduka, Tsutomu Nishida, Atsushi Okuda, Hiroyuki Watanabe, Hideharu Shimozawa, Nobuhiro Nakamura, Kenichi Kaku, Daisuke Miura, Koichi Nakata, Masaki Nonaka, Koji Takahashi, Haruki Mori
  • Publication number: 20190369514
    Abstract: A method for producing an electrophotographic photosensitive member having a photosensitive layer and a protective layer above a support in this order includes: forming a coating film for a protective layer by coating a coating liquid for the protective layer for forming the protective layer on the photosensitive layer and curing the coating film for the protective layer, in which the coating liquid for the protective layer contains a solvent, a compound represented by a general formula (1), a compound represented by a general formula (2), and a compound represented by a general formula (3) at a specific ratio. In addition, in an electrophotographic photosensitive member having a photosensitive layer and a protective layer above a support in this order, the protective layer is obtained by curing a coating liquid for the protective layer.
    Type: Application
    Filed: May 28, 2019
    Publication date: December 5, 2019
    Inventors: Hiroyuki Watanabe, Tsutomu Nishida, Yuka Ishiduka, Atsushi Okuda, Hideharu Shimozawa, Nobuhiro Nakamura, Koichi Nakata, Haruki Mori, Kenichi Kaku
  • Patent number: 10303085
    Abstract: Provided is an electrophotographic photosensitive member capable of achieving both high leak resistance and reduction in variations in dark part potential and bright part potential due to repeated use even when CB is used for an electrically conductive layer. An electrophotographic photosensitive member including: a support, an electrically conductive layer, and a photosensitive layer, sequentially, wherein the electrically conductive layer contains a binder resin and carbon black, a number average primary particle diameter of the carbon black is 200 nm or more and 500 nm or less, an average inter-particle distance of the carbon black is 200 nm or more and 600 nm or less, a coefficient of variation of an inter-particle distance is 1.2 or less, and SF-1 of the carbon black is 150 or less.
    Type: Grant
    Filed: May 30, 2018
    Date of Patent: May 28, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Taichi Sato, Jumpei Kuno, Kenichi Kaku, Takashi Anezaki, Atsushi Fujii
  • Patent number: 10216105
    Abstract: An electrophotographic photosensitive member includes a support member, an electroconductive layer, and a photosensitive layer in this order. The electroconductive layer contains a binder and particles. Each of the particles include a core made of a substance represented by general formula (1), and a coating layer coating the core and containing an electrically conductive material: M1M2O3??(1) wherein M1 represents an element selected from the group consisting of Sr, Li, Na, K, and Ba, and M2 represents an element selected from the group consisting of Ti, Nb, Ta, and Zr.
    Type: Grant
    Filed: February 23, 2018
    Date of Patent: February 26, 2019
    Assignee: Canon Kabushiki Kaisa
    Inventors: Kenichi Kaku, Takashi Anezaki, Taichi Sato, Jumpei Kuno, Atsushi Fujii
  • Patent number: 10203617
    Abstract: Provided is an electrophotographic photosensitive member which can simultaneously achieve less occurrence of leakage and the definition of an output image even when being an electrophotographic photosensitive member where a layer containing a metal oxide particle is adopted as an electroconductive layer, and which includes a support, an electroconductive layer and a photosensitive layer in this order, wherein the electroconductive layer contains a binder material and a particle represented by general formula (1): TiO2.00?XNY??(1) wherein Ti represents a titanium atom, O represents an oxygen atom, N represents a nitrogen atom and 0.00<Y<X?0.60 is satisfied.
    Type: Grant
    Filed: February 13, 2018
    Date of Patent: February 12, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Jumpei Kuno, Takashi Anezaki, Taichi Sato, Kenichi Kaku, Atsushi Fujii
  • Publication number: 20190004442
    Abstract: An electrophotographic photosensitive member includes an electroconductive support member and a photosensitive layer. The uppermost layer of the electrophotographic photosensitive member defines a surface layer, and the surface layer contains polytetrafluoroethylene particles, a charge transporting material, and polyvinyl acetal. The proportion of the polyvinyl acetal content to the polytetrafluoroethylene particles content in the surface layer is in the range of 0.1% by mass to 15.0% by mass, and the charge transporting material content in the surface layer is 35% by mass or more relative to the total mass of the surface layer.
    Type: Application
    Filed: June 13, 2018
    Publication date: January 3, 2019
    Inventors: Kenichi Kaku, Kaname Watariguchi, Kazuko Araki, Tomohito Ishida, Michiyo Sekiya
  • Patent number: 10162278
    Abstract: Disclosed herein is an electrophotographic photosensitive member in which leakage hardly occurs even in the case of using a layer containing metal oxide particles as an electrically conductive layer in the electrophotographic photosensitive member, and which is compatible with definition in output images, the electrophotographic photosensitive member sequentially including: a support, an electrically conductive layer, and a photosensitive layer, the electrically conductive layer containing a binder material and particles represented by General Formula (1). Nb2.00O5.00-XNY??(1) (In Formula (1), Nb is a niobium atom, O is an oxygen atom, N is a nitrogen atom, and 0.00<Y<X?4.00).
    Type: Grant
    Filed: February 21, 2018
    Date of Patent: December 25, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Jumpei Kuno, Kenichi Kaku, Taichi Sato, Takashi Anezaki, Atsushi Fujii
  • Patent number: 10152002
    Abstract: An electrophotographic photosensitive member includes a support member, an electroconductive layer, and photosensitive layer in this order. The electroconductive layer contains a binder and particles. The particles have a core containing titanium oxide, and a coating layer coating the core and containing titanium oxide doped with niobium or tantalum.
    Type: Grant
    Filed: February 23, 2018
    Date of Patent: December 11, 2018
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takashi Anezaki, Kenichi Kaku, Taichi Sato, Jumpei Kuno, Atsushi Fujii
  • Publication number: 20180348665
    Abstract: Provided is an electrophotographic photosensitive member capable of achieving both high leak resistance and reduction in variations in dark part potential and bright part potential due to repeated use even when CB is used for an electrically conductive layer. An electrophotographic photosensitive member including: a support, an electrically conductive layer, and a photosensitive layer, sequentially, wherein the electrically conductive layer contains a binder resin and carbon black, a number average primary particle diameter of the carbon black is 200 nm or more and 500 nm or less, an average inter-particle distance of the carbon black is 200 nm or more and 600 nm or less, a coefficient of variation of an inter-particle distance is 1.2 or less, and SF-1 of the carbon black is 150 or less.
    Type: Application
    Filed: May 30, 2018
    Publication date: December 6, 2018
    Inventors: Taichi Sato, Jumpei Kuno, Kenichi Kaku, Takashi Anezaki, Atsushi Fujii
  • Publication number: 20180246427
    Abstract: An electrophotographic photosensitive member includes a support member, an electroconductive layer, and a photosensitive layer in this order. The electroconductive layer contains a binder and particles. Each of the particles include a core made of a substance represented by general formula (1), and a coating layer coating the core and containing an electrically conductive material: M1M2O3??(1) wherein M1 represents an element selected from the group consisting of Sr, Li, Na, K, and Ba, and M2 represents an element selected from the group consisting of Ti, Nb, Ta, and Zr.
    Type: Application
    Filed: February 23, 2018
    Publication date: August 30, 2018
    Inventors: Kenichi Kaku, Takashi Anezaki, Taichi Sato, Jumpei Kuno, Atsushi Fujii
  • Publication number: 20180246425
    Abstract: Provided is an electrophotographic photosensitive member which can simultaneously achieve less occurrence of leakage and the definition of an output image even when being an electrophotographic photosensitive member where a layer containing a metal oxide particle is adopted as an electroconductive layer, and which includes a support, an electroconductive layer and a photosensitive layer in this order, wherein the electroconductive layer contains a binder material and a particle represented by general formula (1): TiO2.00?XNY ??(1) wherein Ti represents a titanium atom, O represents an oxygen atom, N represents a nitrogen atom and 0.00<Y<X?0.60 is satisfied.
    Type: Application
    Filed: February 13, 2018
    Publication date: August 30, 2018
    Inventors: Jumpei Kuno, Takashi Anezaki, Taichi Sato, Kenichi Kaku, Atsushi Fujii