Patents by Inventor Tsutomu Nishida

Tsutomu Nishida 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: 20240118655
    Abstract: An object of the present disclosure is to provide an electrophotographic photosensitive member with suppressed positive ghosts, and a process cartridge and an electrophotographic apparatus each including the electrophotographic photosensitive member. The present disclosure provides an electrophotographic photosensitive member having a support and a photosensitive layer on the support; the photosensitive layer comprises (?) a compound represented by the formula (1), and (?) at least one selected from the group consisting of a compound represented by the formula (2) and a compound represented by the formula (3), wherein a content of the (?) with respect to a content of the (?) is 50 to 850 mass ppm in the photosensitive layer.
    Type: Application
    Filed: September 8, 2023
    Publication date: April 11, 2024
    Inventors: KUNIHIKO SEKIDO, SHUHEI IWASAKI, TATSUYA OHSAWA, NAOYUKI MATSUMOTO, ATSUSHI OKUDA, TSUTOMU NISHIDA
  • Publication number: 20240004322
    Abstract: The electrophotographic photosensitive member includes a surface layer containing a binder resin, electroconductive particles, and insulating particles, wherein when a volume resistivity of the insulating particles is represented by R1 [?·cm], a volume resistivity of the electroconductive particles is represented by R2 [?·cm], a ratio of an area of the insulating particles that are exposed to a total area of the surface layer is represented by S1 [%], a ratio of an area of the electroconductive particles that are exposed to the total area of the surface layer is represented by S2 [%], an average exposed height of the insulating particles exposed to a surface of the electrophotographic photosensitive member is represented by L1 [nm], and an average exposed height of the electroconductive particles exposed to the surface of the electrophotographic photosensitive member is represented by L2 [nm], those parameters satisfy specific relational formulae.
    Type: Application
    Filed: June 23, 2023
    Publication date: January 4, 2024
    Inventors: KOHEI MAKISUMI, SHUNTARO WATANABE, TAICHI SATO, TOMOHITO ISHIDA, MASATADA HIROTA, TSUTOMU NISHIDA
  • Publication number: 20230408937
    Abstract: An electrophotographic photosensitive member including a surface layer containing a binder resin and metal oxide particles. An average primary particle diameter of the metal oxide particles measured from a cross-section of the surface layer is 20 to 70 nm. A content ratio of the metal oxide particles in the surface layer measured from the cross-section of the surface layer is 30 to 75 vol % with respect to a total volume of the surface layer.
    Type: Application
    Filed: June 16, 2023
    Publication date: December 21, 2023
    Inventors: TAICHI SATO, SHUNTARO WATANABE, MASATADA HIROTA, KOHEI MAKISUMI, TOMOHITO ISHIDA, TSUTOMU NISHIDA
  • Publication number: 20230333494
    Abstract: The process cartridge is a process cartridge to be removably mounted onto a main body of an electrophotographic apparatus, the process cartridge including: an electrophotographic photosensitive member; a toner; and a developing member, wherein the electrophotographic photosensitive member includes a surface layer that is a polymerized film of a composition containing at least one kind of monofunctional (meth)acrylic compound selected from the group consisting of: a monofunctional (meth)acrylic monomer; and a monofunctional (meth)acrylic oligomer, and at least one kind of tri- or higher functional (meth)acrylic compound selected from the group consisting of: a tri- or higher functional (meth)acrylic monomer; and a tri- or higher functional (meth)acrylic oligomer, wherein the toner contains a toner particle and a hydrotalcite particle as an external additive, and wherein the hydrotalcite particle contains fluorine in filter fitting analysis of STEM-EDS analysis.
    Type: Application
    Filed: March 3, 2023
    Publication date: October 19, 2023
    Inventors: KANAME WATARIGUCHI, CHIHARU NAKAZONO, HIDEHARU SHIMOZAWA, TSUTOMU NISHIDA, ATSUSHI OKUDA, TAIJI KATSURA
  • Publication number: 20230288867
    Abstract: A process cartridge detachably attachable to a main body of an electrophotographic apparatus, the process cartridge including an electrophotographic photosensitive member, a toner, and a developing member that feeds the toner to the electrophotographic photosensitive member, wherein the electrophotographic photosensitive member includes a surface layer containing a (meth)acrylic resin having a urethane structure, the toner includes a toner particle and a hydrotalcite particle as an external additive, and the hydrotalcite particle contains fluorine in filter fitting analysis in STEM-EDS analysis.
    Type: Application
    Filed: February 27, 2023
    Publication date: September 14, 2023
    Inventors: HIDEHARU SHIMOZAWA, KANAME WATARIGUCHI, CHIHARU NAKAZONO, TSUTOMU NISHIDA, ATSUSHI OKUDA, TAIJI KATSURA, YUICHI KIKUCHI
  • Publication number: 20230288826
    Abstract: Provided is a process cartridge removably mountable onto a main body of an electrophotographic apparatus, the process cartridge comprising an electrophotographic photosensitive member, a toner, and a developing member configured to supply the toner to the electrophotographic photosensitive member, wherein, in filter fitting analysis in STEM-EDS analysis, a hydrotalcite particle comprises fluorine, and wherein, when a number-average primary particle diameter of a particle A is represented by “m” [nm], a content ratio of the particle A with respect to the surface layer is represented by “p” [vol %], and a number-average primary particle diameter of the hydrotalcite particle is represented by “h” [nm], the “m”, the “p”, and the “h” satisfy the following expressions, respectively: 5?m?300??Expression (1); 5?p?40??Expression (2); and 60?h?1,000??Expression (3).
    Type: Application
    Filed: March 6, 2023
    Publication date: September 14, 2023
    Inventors: CHIHARU NAKAZONO, KANAME WATARIGUCHI, HIDEHARU SHIMOZAWA, TSUTOMU NISHIDA, ATSUSHI OKUDA, TAIJI KATSURA, YUICHI KIKUCHI
  • Patent number: 11703773
    Abstract: An electrophotographic photosensitive member that is excellent in image smearing resistance and low torque while maintaining its electrophotographic characteristic. The electrophotographic photosensitive member is an electrophotographic photosensitive member including, in this order: a support; a photosensitive layer; and a protection layer as a surface layer, wherein the protection layer has a surface having a developed area ratio Sdr of 1.0% to 40.0%, and wherein an A value represented by the following formula (1) is 0.10 to 0.27: A=S1/S2 . . . formula (1), where, in the formula (1), S1 represents a peak area based on C?C stretching vibration of an aromatic ring by attenuated total reflection Fourier transform infrared spectroscopy, and S2 represents a peak area based on C?O stretching vibration of an ester group by the same method.
    Type: Grant
    Filed: February 24, 2022
    Date of Patent: July 18, 2023
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tsutomu Nishida, Yuka Ishiduka, Tatsuya Ohsawa
  • Patent number: 11619888
    Abstract: An electrophotographic image forming apparatus in which streak-like banding to be formed in an electrophotographic photosensitive member is suppressed. The electrophotographic image forming apparatus includes an electrophotographic photosensitive member, which has a protective layer, and a developer carrying member for supplying a developer. The protective layer contains a cured product containing an aromatic ring and an ester group, by attenuated total reflection Fourier transform infrared spectroscopy, when a peak area based on C?C stretching vibration of the aromatic ring is represented by S1, and a peak area based on C?O stretching vibration of the ester group is represented by S2, an area ratio S1/S2 is 0.10 to 0.27, and a rotation speed ratio D1/D2 of a rotation speed D1 of the developer carrying member to a rotation speed D2 of the electrophotographic photosensitive member is 0.80 to 1.20.
    Type: Grant
    Filed: February 25, 2022
    Date of Patent: April 4, 2023
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yuka Ishiduka, Tsutomu Nishida, Tatsuya Ohsawa
  • Patent number: 11500301
    Abstract: An electrophotographic photosensitive member, which is suppressed in occurrence of fogging and is excellent in abrasion resistance. In the electrophotographic photosensitive member, an outermost surface layer of the electrophotographic photosensitive member comprises a polymerized product of a composition comprising at least a polyrotaxane and a monomer having a polymerizable reactive group, and a chain molecule of the polyrotaxane has two blocking groups at both terminals thereof, and a (meth)acryloyloxy group of a cyclic molecule of the polyrotaxane forms a bond.
    Type: Grant
    Filed: January 21, 2021
    Date of Patent: November 15, 2022
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Hideharu Shimozawa, Kenichi Kaku, Tsutomu Nishida, Kazunori Noguchi, Akihiro Maruyama, Kaname Watariguchi, Takashi Anezaki, Haruyuki Tsuji
  • Patent number: 11493853
    Abstract: An electrophotographic photosensitive member having a support and a photosensitive layer on the support, wherein the electrophotographic photosensitive member comprises a surface layer comprising a polymerization product of a composition containing polyrotaxane and a charge transporting substance, and the polymerization product including a bond between the polyrotaxane and the charge transporting substance.
    Type: Grant
    Filed: January 14, 2021
    Date of Patent: November 8, 2022
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hideharu Shimozawa, Kenichi Kaku, Tsutomu Nishida, Kazunori Noguchi, Akihiro Maruyama, Kaname Watariguchi, Takashi Anezaki, Haruyuki Tsuji
  • Publication number: 20220276580
    Abstract: An electrophotographic image forming apparatus in which streak-like banding to be formed in an electrophotographic photosensitive member is suppressed. The electrophotographic image forming apparatus comprises an electrophotographic photosensitive member, which has a protective layer, and a developer carrying member for supplying a developer. The protective layer contains a cured product containing an aromatic ring and an ester group, by attenuated total reflection Fourier transform infrared spectroscopy, when a peak area based on C?C stretching vibration of the aromatic ring is represented by S1, and a peak area based on C?O stretching vibration of the ester group is represented by S2, an area ratio S1/S2 is 0.10 to 0.27, and a rotation speed ratio D1/D2 of a rotation speed D1 of the developer carrying member to a rotation speed D2 of the electrophotographic photosensitive member is 0.80 to 1.20.
    Type: Application
    Filed: February 25, 2022
    Publication date: September 1, 2022
    Inventors: Yuka Ishiduka, Tsutomu Nishida, Tatsuya Ohsawa
  • Publication number: 20220276576
    Abstract: An electrophotographic photosensitive member that is excellent in image smearing resistance and low torque while maintaining its electrophotographic characteristic. The electrophotographic photosensitive member is an electrophotographic photosensitive member comprising, in this order: a support; a photosensitive layer; and a protection layer as a surface layer, wherein the protection layer has a surface having a developed area ratio Sdr of 1.0% to 40.0%, and wherein an A value represented by the following formula (1) is 0.10 to 0.27: A=S1/S2 . . . formula (1), where, in the formula (1), S1 represents a peak area based on C?C stretching vibration of an aromatic ring by attenuated total reflection Fourier transform infrared spectroscopy, and S2 represents a peak area based on C?O stretching vibration of an ester group by the same method.
    Type: Application
    Filed: February 24, 2022
    Publication date: September 1, 2022
    Inventors: Tsutomu Nishida, Yuka Ishiduka, Tatsuya Ohsawa
  • Patent number: 11392050
    Abstract: A process cartridge which allows any spot and stripe as image defects to be suppressed is provided. A process cartridge, in which an electroconductive layer of a charging member has a matrix including a first rubber, and domains dispersed in the matrix, the domains include a second rubber and an electron electroconductive agent, at least some of the domains are exposed on a surface of the charging member, when a volume resistivity of the matrix is 105 times or more a volume resistivity of the domains, a protective layer of an electrophotographic photosensitive member includes a metal oxide particle, and when a number average primary particle size of the metal oxide particle is defined as Sm and an average value of equivalent circle diameters of the domains is defined as Sd, the Sd/Sm satisfies the following expression (1): 0.5<Sd/Sm<100 . . . expression (1).
    Type: Grant
    Filed: October 14, 2020
    Date of Patent: July 19, 2022
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Tsutomu Nishida, Yuka Ishiduka, Kenichi Kaku, Nobuhiro Nakamura, Hiroyuki Watanabe, Hideharu Shimozawa, Atsushi Okuda, Yuichi Kikuchi, Kazuhiro Yamauchi
  • Patent number: 11366402
    Abstract: There is provided a process cartridge detachably attachable to a main body of an electrophotographic apparatus, the process cartridge including an electrophotographic photosensitive member and a charging member, wherein an outer surface of the charging member is composed of at least a matrix and at least a part of domains, a volume resistivity of the matrix is 1.0×105 times or more of a volume resistivity of the domain, an average value Sd of circle equivalent diameters of the domains observed on the outer surface of the charging member is in a predetermined range, the electrophotographic photosensitive member contains a support, a photosensitive layer, and a protective layer in this order and when a surface roughness of the protective layer is measured, each of a protruding valley portion Rvk, a load length ratio Mr2, and Sd/Rvk is in a predetermined range.
    Type: Grant
    Filed: October 14, 2020
    Date of Patent: June 21, 2022
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yuka Ishiduka, Tsutomu Nishida, Hideharu Shimozawa, Nobuhiro Nakamura, Hiroyuki Watanabe, Kenichi Kaku, Kazuhiro Yamauchi, Yuichi Kikuchi, Kazuhisa Shida, Atsushi Okuda
  • Patent number: 11256186
    Abstract: The present disclosure provides an electrophotographic photosensitive member that suppresses electric potential fluctuations in repeated use. The electrophotographic photosensitive member includes a support, a photosensitive layer and a protective layer, in this order, wherein the photosensitive layer includes a compound having a structure represented by formula (1), and the protective layer includes a resin having a structure represented by formula (2) and a structure represented by formula (3).
    Type: Grant
    Filed: February 10, 2020
    Date of Patent: February 22, 2022
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Hideharu Shimozawa, Tsutomu Nishida, Atsushi Okuda, Yuka Ishiduka, Kenichi Kaku, Nobuhiro Nakamura, Hiroyuki Watanabe
  • Publication number: 20210240093
    Abstract: An electrophotographic photosensitive member having a support and a photosensitive layer on the support, wherein the electrophotographic photosensitive member comprises a surface layer comprising a polymerization product of a composition containing polyrotaxane and a charge transporting substance, and the polymerization product including a bond between the polyrotaxane and the charge transporting substance.
    Type: Application
    Filed: January 14, 2021
    Publication date: August 5, 2021
    Inventors: Hideharu Shimozawa, Kenichi Kaku, Tsutomu Nishida, Kazunori Noguchi, Akihiro Maruyama, Kaname Watariguchi, Takashi Anezaki, Haruyuki Tsuji
  • Publication number: 20210240094
    Abstract: An electrophotographic photosensitive member, which is suppressed in occurrence of fogging and is excellent in abrasion resistance. In the electrophotographic photosensitive member, an outermost surface layer of the electrophotographic photosensitive member comprises a polymerized product of a composition comprising at least a polyrotaxane and a monomer having a polymerizable reactive group, and a chain molecule of the polyrotaxane has two blocking groups at both terminals thereof, and a (meth)acryloyloxy group of a cyclic molecule of the polyrotaxane forms a bond.
    Type: Application
    Filed: January 21, 2021
    Publication date: August 5, 2021
    Inventors: Hideharu Shimozawa, Kenichi Kaku, Tsutomu Nishida, Kazunori Noguchi, Akihiro Maruyama, Kaname Watariguchi, Takashi Anezaki, Haruyuki Tsuji
  • Patent number: 11003102
    Abstract: Provided are an electrophotographic apparatus and a process cartridge each capable of suppressing the occurrence of a black spot (white background contamination) in an output image under a low-temperature and low-humidity environment. The electrophotographic apparatus includes: an electrophotographic photosensitive member including a support, a photosensitive layer, and a protective layer in the stated order; an exposing device; a developing device; and a cleaning device, wherein the protective layer has a triarylamine structure and a specific structure at a ratio in a specific range, and a toner contains toner particles each containing at least a resin, and an external additive. The toner has a volume-average particle diameter of 7 ?m or more. The external additive contains a compound containing a titanium atom. The ratio of the mass of the compound containing a titanium atom to the total mass of the toner is 0.6 mass % or more.
    Type: Grant
    Filed: March 11, 2020
    Date of Patent: May 11, 2021
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yuka Ishiduka, Tsutomu Nishida, Hideharu Shimozawa, Nobuhiro Nakamura, Hiroyuki Watanabe
  • Publication number: 20210116826
    Abstract: A process cartridge which allows any spot and stripe as image defects to be suppressed is provided. A process cartridge, in which an electroconductive layer of a charging member has a matrix including a first rubber, and domains dispersed in the matrix, the domains include a second rubber and an electron electroconductive agent, at least some of the domains are exposed on a surface of the charging member, when a volume resistivity of the matrix is 105 times or more a volume resistivity of the domains, a protective layer of an electrophotographic photosensitive member includes a metal oxide particle, and when a number average primary particle size of the metal oxide particle is defined as Sm and an average value of equivalent circle diameters of the domains is defined as Sd, the Sd/Sm satisfies the following expression (1): 0.5<Sd/Sm<100 . . . expression (1).
    Type: Application
    Filed: October 14, 2020
    Publication date: April 22, 2021
    Inventors: Tsutomu Nishida, Yuka Ishiduka, Kenichi Kaku, Nobuhiro Nakamura, Hiroyuki Watanabe, Hideharu Shimozawa, Atsushi Okuda, Yuichi Kikuchi, Kazuhiro Yamauchi
  • Publication number: 20210116833
    Abstract: There is provided a process cartridge detachably attachable to a main body of an electrophotographic apparatus, the process cartridge including an electrophotographic photosensitive member and a charging member, wherein an outer surface of the charging member is composed of at least a matrix and at least a part of domains, a volume resistivity of the matrix is 1.0×105 times or more of a volume resistivity of the domain, an average value Sd of circle equivalent diameters of the domains observed on the outer surface of the charging member is in a predetermined range, the electrophotographic photosensitive member contains a support, a photosensitive layer, and a protective layer in this order and when a surface roughness of the protective layer is measured, each of a protruding valley portion Rvk, a load length ratio Mr2, and Sd/Rvk is in a predetermined range.
    Type: Application
    Filed: October 14, 2020
    Publication date: April 22, 2021
    Inventors: Yuka Ishiduka, Tsutomu Nishida, Hideharu Shimozawa, Nobuhiro Nakamura, Hiroyuki Watanabe, Kenichi Kaku, Kazuhiro Yamauchi, Yuichi Kikuchi, Kazuhisa Shida, Atsushi Okuda