Patents by Inventor Hirofumi Kumoi

Hirofumi Kumoi 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: 9921499
    Abstract: An electrophotographic photosensitive member includes a substrate and a photosensitive layer containing a phthalocyanine pigment. The crystalline particles of the phthalocyanine pigment have a crystallite correlation length r and a particle size R of 400 nm or less, and a parameter k defined by r/R is in the range of 0.17 to 0.42.
    Type: Grant
    Filed: October 26, 2016
    Date of Patent: March 20, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kaname Watariguchi, Shoma Hinata, Kazuko Sakuma, Tsutomu Nishida, Jumpei Kuno, Hirofumi Kumoi, Masato Tanaka, Masataka Kawahara, Yuto Ito, Isao Kawata
  • 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: 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: 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
  • 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
  • Publication number: 20170123330
    Abstract: An electrophotographic photosensitive member includes a substrate and a photosensitive layer containing a phthalocyanine pigment. The crystalline particles of the phthalocyanine pigment have a crystallite correlation length r and a particle size R of 400 nm or less, and a parameter k defined by r/R is in the range of 0.17 to 0.42.
    Type: Application
    Filed: October 26, 2016
    Publication date: May 4, 2017
    Inventors: Kaname Watariguchi, Shoma Hinata, Kazuko Sakuma, Tsutomu Nishida, Jumpei Kuno, Hirofumi Kumoi, Masato Tanaka, Masataka Kawahara, Yuto Ito, Isao Kawata
  • Publication number: 20160252833
    Abstract: An electrophotographic photosensitive member includes a support member, a charge generating layer, and a charge transport layer in that order. The charge generating layer contains a gallium phthalocyanine crystal containing therein at least one amide compound selected from the group consisting of N-methylformamide, N-propylformamide, and N-vinylformamide. The charge transport layer contains fluorine-containing resin particles and a fluorine-containing copolymer.
    Type: Application
    Filed: February 26, 2016
    Publication date: September 1, 2016
    Inventors: Hirofumi Kumoi, Masataka Kawahara, Masato Tanaka
  • Publication number: 20160252829
    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: Application
    Filed: February 25, 2016
    Publication date: September 1, 2016
    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
  • Publication number: 20160252832
    Abstract: Provided is an electrophotographic photosensitive member including a support and a photosensitive layer. The photosensitive layer contains crystalline complexes of hydroxygallium phthalocyanine and chlorogallium phthalocyanine, the crystalline complexes containing an amide compound represented by Formula (1): R1—NHCHO, where R1 represents a methyl group, a propyl group, or a vinyl group.
    Type: Application
    Filed: February 25, 2016
    Publication date: September 1, 2016
    Inventors: Masato Tanaka, Tsutomu Nishida, Hirofumi Kumoi
  • Publication number: 20160252830
    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: Application
    Filed: February 25, 2016
    Publication date: September 1, 2016
    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: 20160154328
    Abstract: To provide an electrophotographic photosensitive member that can allow a high-quality image, in which photomemory after repeated use in a high-speed process is suppressed, to be output, as well as a process cartridge and an electrophotographic apparatus including the electrophotographic photosensitive member. An electrophotographic photosensitive member wherein a charge generating layer includes a gallium phthalocyanine crystal in which an organic compound is contained, wherein the organic compound is at least one compound selected from the group consisting of dimethylsulfoxide, N,N-dimethylformamide, N-methylformamide, N-propylformamide, N-vinylformamide and N-methylpyrrolidone, the content of the organic compound is 0.1% by mass or more and 2.0% by mass or less based on a gallium phthalocyanine in the gallium phthalocyanine crystal, and a charge transporting layer includes a polycarbonate resin having structural units represented by the following formula (1).
    Type: Application
    Filed: November 17, 2015
    Publication date: June 2, 2016
    Inventors: Hirofumi Kumoi, Shoma Hinata, Masataka Kawahara, Masato Tanaka
  • Publication number: 20160154326
    Abstract: The charge generating layer includes a gallium phthalocyanine crystal in which an organic compound (P) is contained, the organic compound (P) is at least one compound selected from the group consisting of dimethylsulfoxide, N,N-dimethylformamide, N-methylformamide, N-propylformamide, N-vinylformamide and N-methylpyrrolidone, the content of the organic compound (P) is 0.1% by mass or more and 1.5% by mass or less based on a gallium phthalocyanine in the gallium phthalocyanine crystal, and the charge transporting layer includes a resin having a siloxane structure, and a compound (Q) having a boiling point of 150° C. or more at 1 atm.
    Type: Application
    Filed: October 29, 2015
    Publication date: June 2, 2016
    Inventors: Hirofumi Kumoi, Shoma Hinata, Masataka Kawahara, Masato Tanaka
  • Patent number: 9274442
    Abstract: Provided an electrophotographic image forming apparatus comprising an electrophotographic photosensitive member and a charging member. The electrophotographic photosensitive member includes a charge transport layer as a surface layer having a matrix-domain structure including specific resins. The charging member comprises an electro-conductive substrate, and an electro-conductive elastic layer. The electro-conductive elastic layer comprises a binder, and holding a bowl-shaped resin particle having an opening, so that at least a part of the bowl-shaped resin particle is exposed, and the charging member has a concavity derived from the opening of the bowl-shaped resin particle on the surface thereof, and a protrusion derived from an edge of the opening of the bowl-shaped resin particle on the surface thereof.
    Type: Grant
    Filed: March 18, 2015
    Date of Patent: March 1, 2016
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Taichi Sato, Tomohito Taniguchi, Noboru Miyagawa, Takehiko Aoyama, Atsushi Uematsu, Masahiro Watanabe, Yuki Yamamoto, Harunobu Ogaki, Akihiro Maruyama, Takashi Anezaki, Daisuke Miura, Hirofumi Kumoi
  • Patent number: 9229342
    Abstract: A surface layer of an electrophotographic photosensitive member contains (?) a particular siloxane-modified resin, (?) a particular compound, and a charge transporting substance. (?) is at least one compound selected from the group consisting of hexanol, heptanol, cyclohexanol, benzyl alcohol, ethylene glycol, 1,4-butanediol, 1,5-pentanediol, diethylene glycol, diethylene glycol ethyl methyl ether, ethylene carbonate, propylene carbonate, nitrobenzene, pyrrolidone, N-methylpyrrolidone, methyl benzoate, ethyl benzoate, benzyl acetate, ethyl 3-ethoxypropionate, acetophenone, methyl salicylate, dimethyl phthalate, and sulfolane.
    Type: Grant
    Filed: November 12, 2013
    Date of Patent: January 5, 2016
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takashi Anezaki, Kazuhisa Shida, Masashi Nishi, Hirofumi Kumoi, Daisuke Tanaka, Kazumichi Sugiyama
  • Patent number: 9164406
    Abstract: The charge transporting layer as the surface layer of an electrophotographic photosensitive member includes a charge transporting substances represented by any one of formulae (1) to (5), a specific compound, and a specific resin (binder resin). The specific compound is hexanol, heptanol, cyclohexanol, benzyl alcohol, ethylene glycol, 1,4-butanediol, 1,5-pentanediol, diethylene glycol, diethylene glycol ethyl methyl ether, ethylene carbonate, propylene carbonate, nitrobenzene, pyrrolidone, N-methylpyrrolidone, methyl benzoate, ethyl benzoate, benzyl acetate, ethyl 3-ethoxypropionate, acetophenone, methyl salicylate, dimethyl phthalate, or sulfolane.
    Type: Grant
    Filed: January 10, 2014
    Date of Patent: October 20, 2015
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Masashi Nishi, Takashi Anezaki, Kazuhisa Shida, Hirofumi Kumoi, Daisuke Tanaka, Kazumichi Sugiyama
  • Publication number: 20150277244
    Abstract: Provided an electrophotographic image forming apparatus comprising an electrophotographic photosensitive member and a charging member. The electrophotographic photosensitive member includes a charge transport layer as a surface layer having a matrix-domain structure including specific resins. The charging member comprises an electro-conductive substrate, and an electro-conductive elastic layer. The electro-conductive elastic layer comprises a binder, and holding a bowl-shaped resin particle having an opening, so that at least a part of the bowl-shaped resin particle is exposed, and the charging member has a concavity derived from the opening of the bowl-shaped resin particle on the surface thereof, and a protrusion derived from an edge of the opening of the bowl-shaped resin particle on the surface thereof.
    Type: Application
    Filed: March 18, 2015
    Publication date: October 1, 2015
    Inventors: Taichi Sato, Tomohito Taniguchi, Noboru Miyagawa, Takehiko Aoyama, Atsushi Uematsu, Masahiro Watanabe, Yuki Yamamoto, Harunobu Ogaki, Akihiro Maruyama, Takashi Anezaki, Daisuke Miura, Hirofumi Kumoi
  • Publication number: 20150277249
    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: Application
    Filed: March 20, 2015
    Publication date: October 1, 2015
    Inventors: Daisuke Miura, Yota Ito, Takashi Anezaki, Hirofumi Kumoi
  • Publication number: 20150220007
    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: Application
    Filed: January 28, 2015
    Publication date: August 6, 2015
    Inventors: Yota Ito, Takashi Anezaki, Daisuke Miura, Hirofumi Kumoi
  • Publication number: 20140205941
    Abstract: The charge transporting layer as the surface layer of an electrophotographic photosensitive member includes a charge transporting substances represented by any one of formulae (1) to (5), a specific compound, and a specific resin (binder resin). The specific compound is hexanol, heptanol, cyclohexanol, benzyl alcohol, ethylene glycol, 1,4-butanediol, 1,5-pentanediol, diethylene glycol, diethylene glycol ethyl methyl ether, ethylene carbonate, propylene carbonate, nitrobenzene, pyrrolidone, N-methylpyrrolidone, methyl benzoate, ethyl benzoate, benzyl acetate, ethyl 3-ethoxypropionate, acetophenone, methyl salicylate, dimethyl phthalate, or sulfolane.
    Type: Application
    Filed: January 10, 2014
    Publication date: July 24, 2014
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Masashi Nishi, Takashi Anezaki, Kazuhisa Shida, Hirofumi Kumoi, Daisuke Tanaka, Kazumichi Sugiyama
  • Publication number: 20140134525
    Abstract: A surface layer of an electrophotographic photosensitive member contains (?) a particular siloxane-modified resin, (?) a particular compound, and a charge transporting substance. (?) is at least one compound selected from the group consisting of hexanol, heptanol, cyclohexanol, benzyl alcohol, ethylene glycol, 1,4-butanediol, 1,5-pentanediol, diethylene glycol, diethylene glycol ethyl methyl ether, ethylene carbonate, propylene carbonate, nitrobenzene, pyrrolidone, N-methylpyrrolidone, methyl benzoate, ethyl benzoate, benzyl acetate, ethyl 3-ethoxypropionate, acetophenone, methyl salicylate, dimethyl phthalate, and sulfolane.
    Type: Application
    Filed: November 12, 2013
    Publication date: May 15, 2014
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Takashi Anezaki, Kazuhisa Shida, Masashi Nishi, Hirofumi Kumoi, Daisuke Tanaka, Kazumichi Sugiyama