Patents by Inventor Koichi Nakata

Koichi Nakata 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: 10761442
    Abstract: Provided are an electrophotographic photosensitive member including a support and a photosensitive layer above the support, in which a surface layer of the electrophotographic photosensitive member includes a polymerization product of a composition containing a specific hole transporting compound, and an electrophotographic apparatus and a process cartridge including the electrophotographic photosensitive member. Also provided is a method of producing the electrophotographic photosensitive member, including (i) forming a coating film of a coating solution for a surface layer which is a composition containing a specific hole transporting compound, and (ii) forming the surface layer of the electrophotographic photosensitive member by a polymerization reaction of the composition containing the specific hole transporting compound.
    Type: Grant
    Filed: June 4, 2019
    Date of Patent: September 1, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Koichi Nakata, Haruki Mori, Shubun Kujirai, Shinji Takagi, Isao Kawata, Yuto Ito, Ryuji Higashi
  • Publication number: 20200272065
    Abstract: An electrophotographic photoreceptor includes a support, a photosensitive layer, and a protection layer. The protection layer contains a copolymer of a compound having a specific frame and a hole-transporting compound containing a specific polarizable functional group.
    Type: Application
    Filed: February 7, 2020
    Publication date: August 27, 2020
    Inventors: Haruki Mori, Koichi Nakata, Shubun Kujirai
  • Publication number: 20200249590
    Abstract: An electrophotographic photosensitive member which satisfies wear resistance and electrical properties, further has high image deletion prevention properties under a high temperature and high humidity environment, and a small potential variation under a low temperature and low humidity environment is provided. The electrophotographic photosensitive member includes a surface layer containing a polymerization product of a hole transporting compound having a specific structure.
    Type: Application
    Filed: January 30, 2020
    Publication date: August 6, 2020
    Inventors: Koichi Nakata, Haruki Mori, Shubun Kujirai
  • Publication number: 20200218171
    Abstract: Provided is an electrophotographic photosensitive member including a surface layer containing: a copolymerization product of a composition containing a hole-transportable compound having a chain-polymerizable functional group and a compound having a specific structure; and metal oxide particles.
    Type: Application
    Filed: December 31, 2019
    Publication date: July 9, 2020
    Inventors: Eileen Takeuchi, Koichi Nakata, Shubun Kujirai, Haruki Mori
  • Publication number: 20200201200
    Abstract: The present disclosure provides an electrophotographic photosensitive member that has mechanical durability, and can achieve both of suppression of an image flow and adequate electrical characteristics.
    Type: Application
    Filed: December 12, 2019
    Publication date: June 25, 2020
    Inventors: Ryoichi Tokimitsu, Koichi Nakata, Haruki Mori, Shubun Kujirai
  • Patent number: 10670979
    Abstract: An electrophotographic photosensitive member has a surface layer that contains a polymer of a hole transport material having at least one monovalent polymerizable functional group.
    Type: Grant
    Filed: May 16, 2018
    Date of Patent: June 2, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Koichi Nakata, Haruki Mori, Shinji Takagi, Koichi Suzuki, Ryuji Higashi, Isao Kawata, Hajime Muta, Yuto Ito, Masaki Nonaka
  • 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
  • Publication number: 20190391504
    Abstract: Provided are an electrophotographic photosensitive member including a support and a photosensitive layer above the support, in which a surface layer of the electrophotographic photosensitive member includes a polymerization product of a composition containing a specific hole transporting compound, and an electrophotographic apparatus and a process cartridge including the electrophotographic photosensitive member. Also provided is a method of producing the electrophotographic photosensitive member, including (i) forming a coating film of a coating solution for a surface layer which is a composition containing a specific hole transporting compound, and (ii) forming the surface layer of the electrophotographic photosensitive member by a polymerization reaction of the composition containing the specific hole transporting compound.
    Type: Application
    Filed: June 4, 2019
    Publication date: December 26, 2019
    Inventors: Koichi Nakata, Haruki Mori, Shubun Kujirai, Shinji Takagi, Isao Kawata, Yuto Ito, Ryuji Higashi
  • 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: 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: 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: 20190361365
    Abstract: Provided is an electrophotographic photosensitive member that suppresses image smearing at the time of its repeated use, and expresses satisfactory wear resistance and electric characteristics. The electrophotographic photosensitive member includes a support and a photosensitive layer in the stated order, wherein a surface layer of the electrophotographic photosensitive member contains a copolymer of a hole-transportable compound having a chain-polymerizable functional group and a specific compound having maleimide groups.
    Type: Application
    Filed: May 20, 2019
    Publication date: November 28, 2019
    Inventors: Haruki Mori, Koichi Nakata, Masaki Nonaka, Shinji Takagi
  • Patent number: 10488771
    Abstract: A surface layer of an electrophotographic photosensitive member contains a cured product of a composition containing a hole transport compound having an acryloyloxy group or a methacryloyloxy group, and a compound having a specific structure.
    Type: Grant
    Filed: September 20, 2018
    Date of Patent: November 26, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Haruki Mori, Masaki Nonaka, Koichi Nakata, Shinji Takagi
  • Patent number: 10488769
    Abstract: Provided is an electrophotographic photosensitive member, wherein a surface layer of the electrophotographic photosensitive member contains a copolymer of a hole-transportable compound having a polymerizable functional group and a compound represented by the following general formula (1).
    Type: Grant
    Filed: August 13, 2018
    Date of Patent: November 26, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Koichi Nakata, Shinji Takagi, Haruki Mori, Masaki Nonaka, Shubun Kujirai
  • Patent number: 10451984
    Abstract: A coating film of a coating liquid for a surface layer, the coating liquid containing a hole transporting compound having a chain-polymerizable functional group and a compound having a specified structure, is cured to thereby form a surface layer of an electrophotographic photosensitive member.
    Type: Grant
    Filed: May 3, 2018
    Date of Patent: October 22, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Haruki Mori, Masaki Nonaka, Shinji Takagi, Koichi Nakata
  • Patent number: 10310395
    Abstract: Provided are an electrophotographic photosensitive member capable of satisfying abrasion resistance and electrical properties and suppressing image deletion, and an electrophotographic apparatus and a process cartridge having the electrophotographic photosensitive member. A surface layer of the electrophotographic photosensitive member contains a polymer of a hole transport material having a polymerizable functional group, wherein the hole transport material has a specific structure.
    Type: Grant
    Filed: June 7, 2018
    Date of Patent: June 4, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Koichi Nakata, Haruki Mori, Shinji Takagi, Masaki Nonaka, Ryoichi Tokimitsu
  • Publication number: 20190094726
    Abstract: A surface layer of an electrophotographic photosensitive member contains a cured product of a composition containing a hole transport compound having an acryloyloxy group or a methacryloyloxy group, and a compound having a specific structure.
    Type: Application
    Filed: September 20, 2018
    Publication date: March 28, 2019
    Inventors: Haruki Mori, Masaki Nonaka, Koichi Nakata, Shinji Takagi
  • Publication number: 20190056676
    Abstract: Provided is an electrophotographic photosensitive member, wherein a surface layer of the electrophotographic photosensitive member contains a copolymer of a hole-transportable compound having a polymerizable functional group and a compound represented by the following general formula (1).
    Type: Application
    Filed: August 13, 2018
    Publication date: February 21, 2019
    Inventors: Koichi Nakata, Shinji Takagi, Haruki Mori, Masaki Nonaka, Shubun Kujirai
  • Publication number: 20180335708
    Abstract: The present invention relates to an electrophotographic photosensitive member in which a surface layer contains a polymer of a hole transport material having a polymerizable functional group, and the hole transport material has a specific fluorene structure.
    Type: Application
    Filed: May 16, 2018
    Publication date: November 22, 2018
    Inventors: Koichi Nakata, Haruki Mori, Shinji Takagi, Koichi Suzuki, Ryuji Higashi, Isao Kawata, Hajime Muta, Yuto Ito, Masaki Nonaka