Patents by Inventor Kunihiko Sekido

Kunihiko Sekido 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: 20200064749
    Abstract: There is provided an electrophotographic photosensitive member that can achieve both of an adequately high initial sensitivity as the electrophotographic photosensitive member and reduction in the fluctuation of a light portion potential at the time of repeated use. An electrophotographic photosensitive member includes a support, an electroconductive layer and a photosensitive layer in this order, wherein the electroconductive layer contains a binder material and a metal oxide particle; the metal oxide particle has a core material containing a titanium oxide, and a covering layer which covers the core material and contains the titanium oxide; and when the oxygen deficiency ratio of the metal oxide particle is represented by A, the oxygen deficiency ratio of the core material is represented by B, and the oxygen deficiency ratio of the covering layer is represented by C, the Expressions (1) and (2) are satisfied: A?2% (1) and 10×B<C (2).
    Type: Application
    Filed: August 16, 2019
    Publication date: February 27, 2020
    Inventors: Takashi Anezaki, Taichi Sato, Kunihiko Sekido, Masashi Nishi, Atsushi Fujii
  • Publication number: 20200041918
    Abstract: An electrophotographic photosensitive member includes, in sequence, a support, a conductive layer, an undercoat layer, a charge generation layer, and a charge transport layer. The conductive layer is a cured film, and the cured film contains titanium oxide particles doped with niobium. The undercoat layer contains a cured product of a composition that contains an electron transport material having a polymerizable functional group and a resin functionalized with a carboxylic acid derivative.
    Type: Application
    Filed: July 24, 2019
    Publication date: February 6, 2020
    Inventors: Masashi Nishi, Takashi Anezaki, Taichi Sato, Atsushi Fujii, Kunihiko Sekido
  • 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
  • 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: 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
  • Publication number: 20160378001
    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: Application
    Filed: June 16, 2016
    Publication date: December 29, 2016
    Inventors: Masashi Nishi, Kunihiko Sekido, Michiyo Sekiya, Kei Tagami, Akihito Saitoh
  • 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
  • Publication number: 20160377999
    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: Application
    Filed: May 31, 2016
    Publication date: December 29, 2016
    Inventors: Masashi Nishi, Kunihiko Sekido, Michiyo Sekiya, Kei Tagami, Isao Kawata, Yuto Ito, Akihito Saitoh
  • 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: 20160376285
    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: Application
    Filed: June 22, 2016
    Publication date: December 29, 2016
    Inventors: Kei Tagami, Akihito Saitoh, Kunihiko Sekido, Michiyo Sekiya, Masashi Nishi