Patents by Inventor Yota Ito

Yota Ito 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: 10942462
    Abstract: The present disclosure provides an electrophotographic photosensitive member that reduces the accumulation of charge and the leakage which are caused by a repeated use in a long period of time. The electrophotographic photosensitive member has a support, an undercoat layer, a charge generation layer and a charge transport layer in this order, wherein the undercoat layer contains a polyamide resin, and a titanium oxide particle, wherein the titanium oxide particle has been surfacetreated with an organosilicon compound, wherein the undercoat layer satisfies 10???70, where ? represents a degree [%] of hydrophobicity of the titanium oxide particle which has been surfacetreated with the organosilicon compound; and the undercoat layer satisfies 0.015?(?×?)?0.040, where ? represents an average primary particle size [?m] of the titanium oxide particles, and ? represents a weight percentage [wt %] of an Si element of the organosilicon compound with respect to the titanium oxide particle.
    Type: Grant
    Filed: October 30, 2019
    Date of Patent: March 9, 2021
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yota Ito, Akira Sakakibara, Jumpei Kuno, Shuhei Iwasaki, Kohei Makisumi
  • Publication number: 20200393771
    Abstract: The present disclosure provides an electrophotographic photosensitive member that can simultaneously achieve the suppression of the occurrence of the black spot in a charged portion and the suppression of the deterioration in sensitivity of an exposed portion, even after stored in a high-temperature and high-humidity environment. An electrophotographic photosensitive member includes an electro-conductive support, an undercoat layer, a charge generation layer and a charge transport layer in this order, wherein an atomic concentration ratio R of the oxygen atom to the aluminum atom on the surface of the electro-conductive support, as measured by energy dispersive X-ray spectroscopy, satisfies the following Expression (1): 1.6?R??(1) and the undercoat layer includes a titanium oxide particle that is surface-treated with a particular silane compound.
    Type: Application
    Filed: June 3, 2020
    Publication date: December 17, 2020
    Inventors: Shuhei Iwasaki, Akira Sakakibara, Jumpei Kuno, Yota Ito, Kohei Makisumi
  • Patent number: 10831117
    Abstract: Provided is an electrophotographic photosensitive member that is improved in potential stability in long-term use under a high-temperature and high-humidity environment, and does not cause degradation in image quality, such as a low density. The electrophotographic photosensitive member includes: a support; an undercoat layer formed on the support; a charge-generating layer formed directly on the undercoat layer; and a charge-transporting layer formed on the charge-generating layer. The undercoat layer contains a polyamide resin, titanium oxide particles surface-treated with an organic silicon compound, and a compound represented by the following Formula (1), and has a content of the compound represented by the Formula (1) of 4 ppm or more and 80 ppm or less: in the Formula (1), R and R? each independently represent a methyl group or an ethyl group.
    Type: Grant
    Filed: November 18, 2019
    Date of Patent: November 10, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Akira Sakakibara, Yota Ito, Jumpei Kuno, Shuhei Iwasaki, Kohei Makisumi
  • Publication number: 20200264525
    Abstract: An electrophotographic photoreceptor includes a support, an undercoat layer placed on the support, a charge generation layer placed on the undercoat layer, and a charge transport layer placed on the charge generation layer. The undercoat layer contains titanium oxide particles surface-treated with an organosilicon compound that is at least one member selected from the group consisting of compounds represented by formulas (1) to (8) and a polyamide resin. The charge generation layer contains hydroxygallium phthalocyanine.
    Type: Application
    Filed: February 11, 2020
    Publication date: August 20, 2020
    Inventors: Jumpei Kuno, Akira Sakakibara, Yota Ito, Shuhei Iwasaki, Kohei Makisumi
  • Publication number: 20200174385
    Abstract: Provided is an electrophotographic photosensitive member that is improved in potential stability in long-term use under a high-temperature and high-humidity environment, and does not cause degradation in image quality, such as a low density. The electrophotographic photosensitive member includes: a support; an undercoat layer formed on the support; a charge-generating layer formed directly on the undercoat layer; and a charge-transporting layer formed on the charge-generating layer. The undercoat layer contains a polyamide resin, titanium oxide particles surface-treated with an organic silicon compound, and a compound represented by the following Formula (1), and has a content of the compound represented by the Formula (1) of 4 ppm or more and 80 ppm or less: in the Formula (1), R and R? each independently represent a methyl group or an ethyl group.
    Type: Application
    Filed: November 18, 2019
    Publication date: June 4, 2020
    Inventors: Akira Sakakibara, Yota Ito, Jumpei Kuno, Shuhei Iwasaki, Kohei Makisumi
  • Publication number: 20200159137
    Abstract: The present disclosure provides an electrophotographic photosensitive member that reduces the accumulation of charge and the leakage which are caused by a repeated use in a long period of time. The electrophotographic photosensitive member has a support, an undercoat layer, a charge generation layer and a charge transport layer in this order, wherein the undercoat layer contains a polyamide resin, and a titanium oxide particle, wherein the titanium oxide particle has been surfacetreated with an organosilicon compound, wherein the undercoat layer satisfies 10???70, where ? represents a degree [%] of hydrophobicity of the titanium oxide particle which has been surfacetreated with the organosilicon compound; and the undercoat layer satisfies 0.015?(?×?)?0.040, where ? represents an average primary particle size [?m] of the titanium oxide particles, and ? represents a weight percentage [wt %] of an Si element of the organosilicon compound with respect to the titanium oxide particle.
    Type: Application
    Filed: October 30, 2019
    Publication date: May 21, 2020
    Inventors: Yota Ito, Akira Sakakibara, Jumpei Kuno, Shuhei Iwasaki, Kohei Makisumi
  • Patent number: 10416581
    Abstract: An electrophotographic photosensitive member with suppressed potential variation even in the case that a protective layer including a cured material of a composition having a polymerizable functional group is used is provided. An electrophotographic photosensitive member including a support, a charge generation layer, a charge transport layer containing a charge transporting material, and a protective layer, in the order presented, wherein the charge transport layer contains a polycarbonate resin having a structure selected from a group A and a structure selected from a group B, and the protective layer includes a cured material of a composition containing a compound having at least a functional group selected from chain-polymerizable functional groups and sequential polymerizable functional groups.
    Type: Grant
    Filed: August 3, 2017
    Date of Patent: September 17, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yota Ito, Tsutomu Nishida, Shoma Hinata, Tatsuya Yamaai, Akira Sakakibara, Daisuke Miura
  • Publication number: 20190243260
    Abstract: An electrophotographic photosensitive member including: a support, an undercoat layer formed above the support, a charge generation layer formed on the undercoat layer, and a charge transport layer formed above the charge generation layer, wherein the undercoat layer contains a polyamide resin and a titanium oxide particle which is surface-treated with a compound represented by Formula (1): when a volume of the titanium oxide particles to a volume of the polyamide resin in the undercoat layer is a, and an average primary particle diameter of the titanium oxide particles is b [?m], the following Equation (A) is satisfied: Equation (A): 14.0?a/b?19.1; and the charge generation layer contains a charge generating material and a thermoplastic resin having a hydroxyl group and a hydroxyl number of 50 mgKOH/g or more.
    Type: Application
    Filed: February 6, 2019
    Publication date: August 8, 2019
    Inventors: Yota Ito, Jumpei Kuno, Shoma Hinata
  • Publication number: 20190121251
    Abstract: An electrophotographic photosensitive member includes a support, a charge generating layer containing a charge generation material, and a charge transporting layer containing a charge transport material in this order, the charge transporting layer serving as a surface layer. The charge transporting layer contains a polycarbonate resin having a particular structural unit.
    Type: Application
    Filed: December 21, 2018
    Publication date: April 25, 2019
    Inventors: Tsutomu Nishida, Akira Sakakibara, Daisuke Miura, Yota Ito, Shoma Hinata, Tatsuya Yamaai, Nobuo Kosaka
  • Patent number: 10209637
    Abstract: An electrophotographic photosensitive member includes a support, a charge generating layer containing a charge generation material, and a charge transporting layer containing a charge transport material in this order, the charge transporting layer serving as a surface layer. The charge transporting layer contains a polycarbonate resin having a particular structural unit.
    Type: Grant
    Filed: July 28, 2017
    Date of Patent: February 19, 2019
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tsutomu Nishida, Akira Sakakibara, Daisuke Miura, Yota Ito, Shoma Hinata, Tatsuya Yamaai, Nobuo Kosaka
  • Publication number: 20180059558
    Abstract: An electrophotographic photosensitive member with suppressed potential variation even in the case that a protective layer including a cured material of a composition having a polymerizable functional group is used is provided. An electrophotographic photosensitive member including a support, a charge generation layer, a charge transport layer containing a charge transporting material, and a protective layer, in the order presented, wherein the charge transport layer contains a polycarbonate resin having a structure selected from a group A and a structure selected from a group B, and the protective layer includes a cured material of a composition containing a compound having at least a functional group selected from chain-polymerizable functional groups and sequential polymerizable functional groups.
    Type: Application
    Filed: August 3, 2017
    Publication date: March 1, 2018
    Inventors: Yota Ito, Tsutomu Nishida, Shoma Hinata, Tatsuya Yamaai, Akira Sakakibara, Daisuke Miura
  • Publication number: 20180031985
    Abstract: An electrophotographic photosensitive member includes a support, a charge generating layer containing a charge generation material, and a charge transporting layer containing a charge transport material in this order, the charge transporting layer serving as a surface layer. The charge transporting layer contains a polycarbonate resin having a particular structural unit.
    Type: Application
    Filed: July 28, 2017
    Publication date: February 1, 2018
    Inventors: Tsutomu Nishida, Akira Sakakibara, Daisuke Miura, Yota Ito, Shoma Hinata, Tatsuya Yamaai, Nobuo Kosaka
  • Patent number: 9864284
    Abstract: An electrophotographic photosensitive member has a support, a charge generation layer, and a charge transport layer in this order, the charge transport layer containing a charge transport material. The charge transport layer is a surface layer of the electrophotographic photosensitive member and contains a polycarbonate resin having a structural unit selected from group A and a structural unit selected from group B.
    Type: Grant
    Filed: February 25, 2016
    Date of Patent: January 9, 2018
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masataka Kawahara, Hirotoshi Uesugi, Akihiro Maruyama, Hirofumi Kumoi, Masato Tanaka, Hiroyuki Tomono, Shoma Hinata, Yota Ito, Daisuke Miura, Takashi Anezaki, Tatsuya Yamaai, Kazumichi Sugiyama
  • Patent number: 9857704
    Abstract: A process cartridge includes an electrophotographic photosensitive member and a gap retaining member, where the electrophotographic photosensitive member includes a first region having an undercoat layer, a charge generating layer, and a charge transporting layer on a support in this order and a second region having an undercoat layer and a charge transporting layer on a support in this order, the undercoat layer contains a metal oxide particle and any one of an urethane resin, an amino resin, and a polyamide resin as a binder resin, and the charge transporting layer contains a charge transporting substance and at least one selected from the group consisting of a polycarbonate resin and a polyester resin, and where the gap retaining member comes into contact with a surface of the second region of the electrophotographic photosensitive member.
    Type: Grant
    Filed: August 21, 2015
    Date of Patent: January 2, 2018
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yota Ito, Hiroyuki Tomono, Takashi Anezaki, Daisuke Miura, Harunobu Ogaki
  • Patent number: 9851646
    Abstract: Provided is an electrophotographic apparatus, including an electrophotographic photosensitive member, a charging unit arranged in a non-abutment manner with respect to the electrophotographic photosensitive member, a cleaning unit or a developing unit arranged in abutment against the electrophotographic photosensitive member, and a transferring unit.
    Type: Grant
    Filed: February 8, 2017
    Date of Patent: December 26, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Hiroyuki Tomono, Daisuke Miura, Takashi Anezaki, Yota Ito, Harunobu Ogaki
  • Patent number: 9778581
    Abstract: An electrophotographic photosensitive member includes a hole transporting layer containing a polyester resin having a structural unit expressed by formula (1) as a hole transporting substance.
    Type: Grant
    Filed: January 28, 2015
    Date of Patent: October 3, 2017
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yota Ito, Takashi Anezaki, Daisuke Miura, Hirofumi Kumoi
  • Patent number: 9772569
    Abstract: An undercoat layer of an electrophotographic photosensitive member includes a binder resin, and a complex particle composed of a core particle coated with tin oxide doped with zinc.
    Type: Grant
    Filed: May 31, 2016
    Date of Patent: September 26, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Daisuke Tanaka, Kazumichi Sugiyama, Takeshi Murakami, Daisuke Kawaguchi, Yota Ito
  • Patent number: 9753385
    Abstract: An electrophotographic photosensitive member has a support, a charge generation layer, and a charge transport layer in this order, the charge transport layer containing a charge transport material. The charge transport layer is a surface layer of the electrophotographic photosensitive member and contains a polycarbonate resin having a structural unit selected from group A and a structural unit selected from group B (groups A and B defined in the disclosure).
    Type: Grant
    Filed: February 25, 2016
    Date of Patent: September 5, 2017
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yota Ito, Daisuke Miura, Shoma Hinata, Hiroyuki Tomono, Takashi Anezaki, Tatsuya Yamaai, Kazumichi Sugiyama, Masataka Kawahara, Hirotoshi Uesugi, Akihiro Maruyama, Hirofumi Kumoi, Masato Tanaka
  • Publication number: 20170227858
    Abstract: Provided is an electrophotographic apparatus, including an electrophotographic photosensitive member, a charging unit arranged in a non-abutment manner with respect to the electrophotographic photosensitive member, a cleaning unit or a developing unit arranged in abutment against the electrophotographic photosensitive member, and a transferring unit.
    Type: Application
    Filed: February 8, 2017
    Publication date: August 10, 2017
    Inventors: Hiroyuki Tomono, Daisuke Miura, Takashi Anezaki, Yota Ito, Harunobu Ogaki
  • Patent number: 9665020
    Abstract: A charge transporting layer of an electrophotographic photosensitive member contains a polysiloxane resin having a terminal structure represented by the formula (1), at least one selected from the group consisting of a polycarbonate resin A having a structural unit represented by the formula (A) and a polyarylate resin B having a structural unit represented by the formula (B), and a charge transporting substance, wherein the content of the siloxane structure in the polysiloxane resin is not less than 0.5% by mass and not more than 10% by mass based on the total mass of whole resin in the charge transporting layer.
    Type: Grant
    Filed: March 20, 2015
    Date of Patent: May 30, 2017
    Assignee: Canon Kabushiki Kaisha
    Inventors: Daisuke Miura, Yota Ito, Takashi Anezaki, Hirofumi Kumoi