Patents by Inventor Michiyo Sekiya

Michiyo Sekiya 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: 20200409279
    Abstract: An electrophotographic photosensitive member, including a cylindrical support, a charge generating layer formed on the cylindrical support, and a charge transport layer formed on the charge generating layer, in which in the charge generating layer, when a region from a central position of an image forming region to an end position of the image forming region in an axis direction of the cylindrical support is divided equally into five regions, film thicknesses of the charge generating layers in each of the regions satisfy a specific relationship with each other, and in the charge transport layer, when a region from the central position of the image forming region to the end position of the image forming region in the axis direction of the cylindrical support is divided equally into five regions, film thicknesses of the charge transport layers in each of the regions satisfy a specific relationship with each other.
    Type: Application
    Filed: June 18, 2020
    Publication date: December 31, 2020
    Inventors: Michiyo Sekiya, Kaname Watariguchi, Masataka Kawahara, Tomohito Ishida, Kohei Makisumi
  • Publication number: 20200409281
    Abstract: The electrophotographic photosensitive member has: a cylindrical support; a charge generating layer formed on the cylindrical support; and a charge transport layer formed on the charge generating layer, the charge generating layer contains a hydroxygallium phthalocyanine crystal having a particular CuK? characteristic X-ray diffraction peak, a titanyl phthalocyanine crystal having a particular CuK? characteristic X-ray diffraction peak or a chlorogallium phthalocyanine crystal having a particular spectral absorption spectrum as a charge generating material, and in the charge generating layer, with respect to the film thickness of the charge generating layer, when a region from the central position of an image forming area to the end position of the image forming area is divided in the axial direction of the cylindrical support into five equal regions and the average film thickness of the charge generating layer in each region satisfies a specific condition.
    Type: Application
    Filed: June 18, 2020
    Publication date: December 31, 2020
    Inventors: Kaname Watariguchi, Tomohito Ishida, Masataka Kawahara, Michiyo Sekiya, Kohei Makisumi
  • Publication number: 20200409280
    Abstract: Provided is an electrophotographic photosensitive member in which discharge streaks generated in an end portion can be suppressed. The electrophotographic photosensitive member includes a cylindrical support, a charge-generating layer, and a charge-transporting layer in the stated order. In the electrophotographic photosensitive member, when a region between a center position and a 90% position situated at a 90% of a length of from the center position to one end of the electrophotographic photosensitive member in an axial direction thereof from the center position, is defined as a region X, and a region between the 90% position and the end of the electrophotographic photosensitive member is defined as a region Z. Average thicknesses in regions obtained by equally dividing the region X into five and regions obtained by equally dividing the region Z into three satisfy particular relationships.
    Type: Application
    Filed: June 18, 2020
    Publication date: December 31, 2020
    Inventors: Tomohito Ishida, Kaname Watariguchi, Masataka Kawahara, Michiyo Sekiya, Kohei Makisumi
  • 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
  • Patent number: 10372050
    Abstract: The present invention provides an electrophotographic photosensitive member in which a photosensitive layer has strong close adhesiveness even when used repeatedly, and a positive ghost is reduced. An undercoat layer of the electrophotographic photosensitive member contains a cured product of an electron transport material having a polymerizable functional group; a polyolefin resin having at least one group/structure selected from the group consisting of a carboxyl group, an alkoxycarbonyl group and an anhydrous carboxylic acid structure, and a substituted or unsubstituted phenyl group; and an isocyanate compound having two or more isocyanate groups.
    Type: Grant
    Filed: May 17, 2018
    Date of Patent: August 6, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Masashi Nishi, Kunihiko Sekido, Michiyo Sekiya, Hiroyuki Watanabe
  • 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
  • Publication number: 20180341190
    Abstract: The present invention provides an electrophotographic photosensitive member in which a photosensitive layer has strong close adhesiveness even when used repeatedly, and a positive ghost is reduced. An undercoat layer of the electrophotographic photosensitive member contains a cured product of an electron transport material having a polymerizable functional group; a polyolefin resin having at least one group/structure selected from the group consisting of a carboxyl group, an alkoxycarbonyl group and an anhydrous carboxylic acid structure, and a substituted or unsubstituted phenyl group; and an isocyanate compound having two or more isocyanate groups.
    Type: Application
    Filed: May 17, 2018
    Publication date: November 29, 2018
    Inventors: Masashi Nishi, Kunihiko Sekido, Michiyo Sekiya, Hiroyuki Watanabe
  • Patent number: 10095136
    Abstract: An electrophotographic photosensitive member includes a support member, an undercoat layer, and a photosensitive layer adjacent to the undercoat layer in this order, wherein the undercoat layer contains a polymerized product of a composition including an electron transporting material having a polymerizable functional group, a cross-linking agent, and a thermoplastic resin having a polymerizable functional group, and at least one type of particles selected from the group consisting of resin particles having a hollow structure and rubber particles, wherein a content of the electron transporting material in the undercoat layer is 30% by mass or more with respect to a total mass of the composition, and wherein a content of the at least one type of particles in the undercoat layer is 10% by mass or more and 100% by mass or less with respect to the content of the electron transporting material.
    Type: Grant
    Filed: May 4, 2017
    Date of Patent: October 9, 2018
    Assignee: Canon Kabushiki Kaisha
    Inventors: Michiyo Sekiya, Kunihiko Sekido, Masashi Nishi
  • Patent number: 10065969
    Abstract: A method for producing a carboxylic acid anhydride includes heating a composition containing a specific compound in a solvent to yield the carboxylic acid anhydride. The solvent is an aprotic polar solvent having a boiling point of 50° C. or more.
    Type: Grant
    Filed: June 22, 2016
    Date of Patent: September 4, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kei Tagami, Akihito Saitoh, Kunihiko Sekido, Michiyo Sekiya, Masashi Nishi
  • Patent number: 9921498
    Abstract: Provided is an electrophotographic photosensitive member including a support, an undercoat layer formed on the support, and a photosensitive layer formed on the undercoat layer, in which the undercoat layer contains a polymer of a composition containing a compound represented by the formula (1).
    Type: Grant
    Filed: June 20, 2016
    Date of Patent: March 20, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kunihiko Sekido, Masashi Nishi, Michiyo Sekiya, Kei Tagami
  • Patent number: 9864285
    Abstract: Provided is an electrophotographic photosensitive member comprising a support, an intermediate layer formed on the support, a charge generating layer formed directly on the intermediate layer, and a charge transporting layer formed on the charge generating layer, in which the intermediate layer contains a compound represented by the formula (1).
    Type: Grant
    Filed: June 16, 2016
    Date of Patent: January 9, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Masashi Nishi, Kunihiko Sekido, Michiyo Sekiya, Kei Tagami, Yuki Yamamoto
  • Patent number: 9851648
    Abstract: The present invention provides an electrophotographic photosensitive member that allows positive ghost to be reduced even in repeated use. The electrophotographic photosensitive member of the present invention is an electrophotographic photosensitive member wherein an undercoat layer contains a polymerization product of a composition including a compound represented by the following formula (1).
    Type: Grant
    Filed: May 31, 2016
    Date of Patent: December 26, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Masashi Nishi, Kunihiko Sekido, Michiyo Sekiya, Kei Tagami, Isao Kawata, Yuto Ito, Akihito Saitoh
  • Publication number: 20170322501
    Abstract: An electrophotographic photosensitive member includes a support member, an undercoat layer, and a photosensitive layer adjacent to the undercoat layer in this order, wherein the undercoat layer contains a polymerized product of a composition including an electron transporting material having a polymerizable functional group, a cross-linking agent, and a thermoplastic resin having a polymerizable functional group, and at least one type of particles selected from the group consisting of resin particles having a hollow structure and rubber particles, wherein a content of the electron transporting material in the undercoat layer is 30% by mass or more with respect to a total mass of the composition, and wherein a content of the at least one type of particles in the undercoat layer is 10% by mass or more and 100% by mass or less with respect to the content of the electron transporting material.
    Type: Application
    Filed: May 4, 2017
    Publication date: November 9, 2017
    Inventors: Michiyo Sekiya, Kunihiko Sekido, Masashi Nishi
  • Patent number: 9811011
    Abstract: Provided are an electrophotographic photosensitive member comprising: a support, an undercoat layer formed on the support, and a photosensitive layer formed on the undercoat layer, on which the undercoat layer contains one of a compound represented by the formula (1) and a polymer of a composition containing the compound represented by the formula (1).
    Type: Grant
    Filed: June 16, 2016
    Date of Patent: November 7, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Masashi Nishi, Kunihiko Sekido, Michiyo Sekiya, Kei Tagami, Akihito Saitoh
  • Patent number: 9772568
    Abstract: Provided is an electrophotographic photosensitive member including a support, an undercoat layer, and a photosensitive layer in this order, in which: the undercoat layer does not contain a metal oxide, or contains the metal oxide but the content of the metal oxide in the undercoat layer is 10 mass % or less; and the undercoat layer contains a polymerized product of a composition containing at least one kind of anthraquinone derivative selected from the group consisting of a compound represented by the formula (1) and a compound represented by the formula (2).
    Type: Grant
    Filed: March 22, 2016
    Date of Patent: September 26, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kunihiko Sekido, Michiyo Sekiya, Kei Tagami, Masashi Nishi
  • Patent number: 9760030
    Abstract: An electrophotographic photosensitive member includes a laminated body, the laminated body including a support, an undercoat layer, and a charge generating layer. The undercoat layer includes a polymerized product of a composition including an electron transport material represented by formula (1), a cross-linking agent, and a thermoplastic resin having a polymerizable functional group, the laminated body satisfying expressions (2) and (3) Z1—X—Z2??(1) 0.20?|Vd2?Vd1|?2.0??(2) ??10??(3) in which Z1 and Z2 are groups having electron transport property, X is a linker, Vd2 and Vd1 are surface potentials of the charge generating layer after charging and ? is transit time based on a change rate of the surface of the charge generating layer, each as defined in the specification.
    Type: Grant
    Filed: October 19, 2015
    Date of Patent: September 12, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Michiyo Sekiya, Kunihiko Sekido, Kei Tagami, Masashi Nishi
  • Patent number: 9751880
    Abstract: An electrophotographic photosensitive member includes, in the following order, a support member, an undercoat layer adjacent to the support member, and a photosensitive layer adjacent to the undercoat layer. The undercoat layer contains a polymer produced by polymerizing a composition containing a crosslinking agent and a compound expressed by general formula (1): wherein R1 to R11 are defined in the specification.
    Type: Grant
    Filed: October 21, 2015
    Date of Patent: September 5, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Masashi Nishi, Kunihiko Sekido, Michiyo Sekiya, Kei Tagami
  • Patent number: 9535346
    Abstract: An electrophotographic photosensitive member has an undercoat layer containing a polymerized product of a composition including electron transporting substance having a polymerizable functional group and a crosslinking agent, and resin particles. The content of the electron transporting substance is 30% by mass or more and 70% by mass or less based on the total mass of the composition. Protrusions derived from the resin particles in the undercoat layer are formed at an interface between the undercoat layer and the charge generating layer.
    Type: Grant
    Filed: December 12, 2014
    Date of Patent: January 3, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Michiyo Sekiya, Yota Ito, Nobuhiro Nakamura
  • Publication number: 20160378000
    Abstract: Provided is an electrophotographic photosensitive member comprising a support, an intermediate layer formed on the support, a charge generating layer formed directly on the intermediate layer, and a charge transporting layer formed on the charge generating layer, in which the intermediate layer contains a compound represented by the formula (1).
    Type: Application
    Filed: June 16, 2016
    Publication date: December 29, 2016
    Inventors: Masashi Nishi, Kunihiko Sekido, Michiyo Sekiya, Kei Tagami, Yuki Yamamoto
  • Publication number: 20160377998
    Abstract: Provided is an electrophotographic photosensitive member including a support, an undercoat layer formed on the support, and a photosensitive layer formed on the undercoat layer, in which the undercoat layer contains a polymer of a composition containing a compound represented by the formula (1).
    Type: Application
    Filed: June 20, 2016
    Publication date: December 29, 2016
    Inventors: Kunihiko Sekido, Masashi Nishi, Michiyo Sekiya, Kei Tagami