Patents by Inventor Yuka Ishiduka

Yuka Ishiduka 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: 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
  • Publication number: 20190369517
    Abstract: To provide an electrophotographic photosensitive member which does not cause film exfoliation in long-term use. An electrophotographic photosensitive member, having: a support; a layered photosensitive layer; and a protective layer in this order, wherein the protective layer is a single layer, the protective layer includes: at least two specific structures, the two specific structures are included in the protective layer at a mass ratio of 20% or more and 240% or less, and a peak area based on in-plane deformation vibration of terminal olefin (CH2?) of the protective layer and a peak area based on stretching vibration of C?O of acryloyloxy groups, the peak areas being determined by total reflection Fourier transform infrared spectroscopy under conditions where an internal reflection element is Ge, and an incidence angle is 45°, have a fixed relationship.
    Type: Application
    Filed: May 28, 2019
    Publication date: December 5, 2019
    Inventors: Hiroyuki Watanabe, Tsutomu Nishida, Yuka Ishiduka, Atsushi Okuda, Hideharu Shimozawa, Nobuhiro Nakamura, Daisuke Miura
  • 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: 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: 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
  • Publication number: 20190369512
    Abstract: Provided is a process cartridge including: an electrophotographic photoreceptor; a charging unit configured to charge the electrophotographic photoreceptor through abutment against the electrophotographic photoreceptor; a developing unit configured to develop an electrostatic latent image formed on the electrophotographic photoreceptor with a toner to form a toner image; and a cleaning unit configured to remove the toner on the electrophotographic photoreceptor by bringing a blade into abutment against the electrophotographic photoreceptor, wherein the toner includes a toner base containing a coloring agent and a binder resin, and has a surface layer containing an organosilicon polymer having a specific sticking ratio to a toner base, and wherein the electrophotographic photoreceptor includes a supporting member and a surface layer, and the surface layer has a specific universal hardness value and a specific elastic deformation ratio (We).
    Type: Application
    Filed: May 28, 2019
    Publication date: December 5, 2019
    Inventors: Atsushi Okuda, Tsutomu Nishida, Yuka Ishiduka, Nobuhiro Nakamura, Hiroyuki Watanabe, Hideharu Shimozawa, Satoshi Otsuji, Kentaro Yamawaki, Daisuke Miura
  • Publication number: 20190310561
    Abstract: An electrophotographic photosensitive member includes an undercoat layer, a charge generation layer, and a charge transport layer in this order. The undercoat layer contains a cured product of a composition containing an electron transport material, a particle having an average primary particle size of 10 nm or more, and a silicone oil. A content of the particle in the undercoat layer is 3% by mass or more and 20% by mass or less. A content of the silicone oil in the undercoat layer is 0.01% by mass or more and 10% by mass or less relative to the content of the particle.
    Type: Application
    Filed: April 5, 2019
    Publication date: October 10, 2019
    Inventors: Masashi Nishi, Kunihiko Sekido, Yuka Ishiduka, Akihiro Maruyama
  • Publication number: 20190265601
    Abstract: The present invention provides an electrophotographic photosensitive member sequentially including: a support; a photosensitive layer; and a protection layer formed on the support, wherein the protection layer has a triarylamine structure and a specific cyclic structure, and a specific A-value obtained by measurement using total reflection Fourier transform infrared spectroscopy is 0.010 or more and 0.050 or less.
    Type: Application
    Filed: February 27, 2019
    Publication date: August 29, 2019
    Inventors: Tsutomu Nishida, Atsushi Okuda, Yuka Ishiduka, Nobuhiro Nakamura, Hiroyuki Watanabe, Hideharu Shimozawa
  • Publication number: 20190265603
    Abstract: An electrophotographic photosensitive member having a protective layer wherein the density unevenness among output images is reduced with abrasion resistance maintained is provided. The present invention is an electrophotographic photosensitive member having a support, a photosensitive layer and a protective layer in this order, wherein the protective layer has a triarylamine structure and a cyclic structure represented by the formula (1) or (2): and an A value expressed by expression (4), A=S1/S2, wherein, in expression (4), S1 is a peak area based on in-plane deformation vibration of terminal olefin (CH2?), and S2 is a peak area based on stretching vibration of C?O among peak areas of a spectrum obtained by measuring a surface of the protective layer by total reflection Fourier transform infrared spectroscopy using Ge as an internal reflection element and using a measurement condition of 45° as an incidence angle is from 0.065 to 0.100.
    Type: Application
    Filed: February 11, 2019
    Publication date: August 29, 2019
    Inventors: Hideharu Shimozawa, Tsutomu Nishida, Atsushi Okuda, Yuka Ishiduka, Nobuhiro Nakamura, Hiroyuki Watanabe
  • Publication number: 20190265602
    Abstract: Provided is an image-forming apparatus including: an electrophotographic photosensitive member including a support, a photosensitive layer, and a protective layer in the stated order; a charging unit; an exposing unit; a developing unit; a transferring unit; and a cleaning unit configured to clean off the toner, which remains on the electrophotographic photosensitive member after the transfer of the toner image from the electrophotographic photosensitive member by the transferring unit, with a cleaning blade, wherein the electrophotographic photosensitive member includes, on a surface thereof, a fatty acid metal salt-supplying unit configured to supply a fatty acid metal salt having 16 or more and 18 or less carbon atoms, and wherein the protective layer has a triphenylamine structure, one of an acryloyloxy group and a methacryloyloxy group, and a specific structure.
    Type: Application
    Filed: February 27, 2019
    Publication date: August 29, 2019
    Inventors: Nobuhiro Nakamura, Tsutomu Nishida, Atsushi Okuda, Yuka Ishiduka, Hiroyuki Watanabe, Hideharu Shimozawa
  • Patent number: 10114301
    Abstract: An electrophotographic photoreceptor abuts against a charging member and/or a developer carrying member with an abutting member therebetween, has a first portion and a second portion abutting against the abutting member along the longitudinal direction of the photoreceptor, and includes a support, a charge generating layer containing a charge generation material, and a surface layer in this order. The first portion includes an undercoat layer containing a polymer of a composition containing an electron transport material and a crosslinking agent and being contiguous with the surface of the charge generating layer facing the support. The second portion includes (i) an intermediate layer being disposed between and being contiguous with the support and the charge generating layer and/or (ii) an intermediate layer being disposed between and being contiguous with the charge generating layer and the surface layer, wherein the intermediate layers each have a Martens hardness of 500 N/mm2 or less.
    Type: Grant
    Filed: October 5, 2016
    Date of Patent: October 30, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Atsushi Okuda, Yuka Ishiduka, Atsushi Fujii, Akihiro Maruyama, Kazunori Noguchi, Nobuhiro Nakamura, Yuki Yamamoto, Kazuko Araki, Tatsuya Ikezue
  • Patent number: 9817326
    Abstract: A support, a conductive layer, and an intermediate layer of an electrophotographic photosensitive member have a particular surface profile. The intermediate layer is a cured film containing particles.
    Type: Grant
    Filed: January 25, 2016
    Date of Patent: November 14, 2017
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yuki Yamamoto, Atsushi Fujii, Atsushi Okuda, Yuka Ishiduka, Kazunori Noguchi, Akihiro Maruyama, Nobuhiro Nakamura, Kazuko Sakuma
  • Patent number: 9811008
    Abstract: An image forming method in which a surface layer of an electrophotographic photosensitive member contains a compound having a specific structure in an amount of 0.1% to 10% by mass based on the total mass of the surface layer, and in a charged region of the surface of the electrophotographic photosensitive member charged in a charging step, a non-image forming region in which an electrostatic latent image is not formed is not irradiated with destaticizing light or is irradiated with reduced destaticizing light.
    Type: Grant
    Filed: July 8, 2016
    Date of Patent: November 7, 2017
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazunori Noguchi, Yuka Ishiduka, Yuki Yamamoto, Atsushi Okuda, Akihiro Maruyama, Atsushi Fujii, Nobuhiro Nakamura, Kazuko Sakuma
  • Patent number: 9804512
    Abstract: An electrophotographic photosensitive member includes a support, an undercoat layer which contains a metal oxide particle and is formed on the support, a charge generating layer formed on the undercoat layer, and a charge transporting layer formed on the charge generating layer. Either or both of the undercoat layer and the charge generating layer contain a compound represented by formula (1).
    Type: Grant
    Filed: March 6, 2014
    Date of Patent: October 31, 2017
    Assignee: Canon Kabushiki Kaisha
    Inventors: Ryoichi Tokimitsu, Yuka Ishiduka, Wataru Kitamura, Mai Murakami, Kan Tanabe
  • Patent number: 9778582
    Abstract: An electrophotographic photosensitive member includes an undercoat layer that includes metal oxide particles and a compound having at least three hydroxyl groups and a carbonyl or dicarbonyl group.
    Type: Grant
    Filed: November 29, 2012
    Date of Patent: October 3, 2017
    Assignee: Canon Kabushiki Kaisha
    Inventors: Wataru Kitamura, Ryoichi Tokimitsu, Yuka Ishiduka, Mai Murakami, Kenichi Kaku
  • Patent number: 9726992
    Abstract: An electrophotographic photosensitive member comprises a support, an undercoat layer, a charge generation layer and a hole transporting layer disposed in this order. The undercoat layer contains silica particles and a polymer of a composition including an electron transporting material having a polar group selected from the group consisting of a hydroxy group, a thiol group, an amino group, a carboxy group and a methoxy group, and a cross-linking agent. The content of the electron transporting material in the composition is 30 to 70 mass % relative to the total mass of the composition and the content of the silica particles in the undercoat layer is 1 to 30 mass % relative to the total mass of the electron transporting material.
    Type: Grant
    Filed: January 12, 2016
    Date of Patent: August 8, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kazuko Sakuma, Yuka Ishiduka, Atsushi Okuda, Kazunori Noguchi, Yuki Yamamoto, Atsushi Fujii, Akihiro Maruyama, Nobuhiro Nakamura
  • Patent number: 9684277
    Abstract: Provided are a process cartridge and an image-forming method each of which has a satisfactory cleaning property even at the initial stage of the use of a brand-new process cartridge or electrophotographic apparatus, and hence can suppress a reduction in image quality due to the contamination of a charging member. The charge transporting layer of an electrophotographic photosensitive member contains a specific polyarylate resin or polycarbonate resin, and a toner contains a specific fine particle on the surface of a toner particle.
    Type: Grant
    Filed: November 13, 2015
    Date of Patent: June 20, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yuki Yamamoto, Atsushi Okuda, Yuka Ishiduka, Shuhei Moribe, Koji Nishikawa