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: 20250244687
    Abstract: Provided is an electrophotographic apparatus including: an electrophotographic photosensitive member; a charging unit; an exposing unit; and a developing unit, wherein the electrophotographic photosensitive member includes a monolayer type photosensitive layer containing a charge generating material, a hole transporting material, an electron transporting material, and a first binder resin, wherein the photosensitive layer contains, as the first binder resin, a polyester resin having specific structural units, wherein the developing unit is a developing roller including a shaft body, an elastic layer arranged on an outer periphery of the shaft body, and a coating layer arranged on an outer periphery of the elastic layer, and wherein the coating layer contains a second binder resin and a silica particle.
    Type: Application
    Filed: January 16, 2025
    Publication date: July 31, 2025
    Inventors: FUMIYUKI HIYAMA, TAICHI SATO, AKIRA SAKAKIBARA, TSUTOMU NISHIDA
  • Publication number: 20250208527
    Abstract: An electrophotographic photosensitive member that can resist mass printing. The electrophotographic photosensitive member is an electrophotographic photosensitive member including a surface layer containing a binder resin and inorganic particles. The surface layer contains a urethane resin as the binder resin, wherein the value of the ratio of the volume of the inorganic particles to the volume of the binder resin in the surface layer is 0.10 or more and 3.0 or less. Protrusions derived from the inorganic particles are present on the surface of the surface layer. The inorganic particles to be incorporated into the surface layer have a number-based average primary particle diameter of 10 nm or more and 500 nm or less. The surface of the surface layer has a maximum height roughness Rz of 10 nm or more and 760 nm or less.
    Type: Application
    Filed: December 16, 2024
    Publication date: June 26, 2025
    Inventors: NAO HIGUCHI, TSUTOMU NISHIDA, SHUNTARO WATANABE, TAICHI SATO, FUMIYUKI HIYAMA, KENTARO TANAKA
  • Publication number: 20250199463
    Abstract: A process cartridge being detachably attachable onto a main body of an electrophotographic apparatus, the process cartridge including an electrophotographic photosensitive member, a developing roller configured to develop an electrostatic latent image formed on the electrophotographic photosensitive member, and a toner-supplying roller arranged in contact with the developing roller and configured to supply toner to the developing roller. The developing roller and the toner-supplying roller are configured to be rotated under specific conditions. The electrophotographic photosensitive member includes a surface layer that is a polymerized film of a composition containing at least one kind of (meth)acrylic compound. The surface layer contains a metal oxide particle.
    Type: Application
    Filed: December 13, 2024
    Publication date: June 19, 2025
    Inventors: KANAME WATARIGUCHI, CHIHARU AKIYAMA, TAICHI SATO, NAO HIGUCHI, TSUTOMU NISHIDA
  • Publication number: 20250164901
    Abstract: Provided is an electrophotographic photosensitive member including: a support; and a photosensitive layer. The photosensitive layer contains a binder resin, a charge generating material, an electron transporting material, and a hole transporting material. The binder resin contains a polyarylate resin having a particular structural unit. The hole transporting material contains a particular compound.
    Type: Application
    Filed: November 8, 2024
    Publication date: May 22, 2025
    Inventors: MASASHI NISHI, TSUTOMU NISHIDA, AKIHIRO MARUYAMA, NORIFUMI MURANAKA
  • Publication number: 20250164902
    Abstract: Provided is an electrophotographic photosensitive member including: a support; and a photosensitive layer. The photosensitive layer contains a binder resin, a charge generating material, an electron transporting material, and a hole transporting material. The binder resin contains a polyarylate resin having a particular structural unit. The hole transporting material contains a particular compound.
    Type: Application
    Filed: November 8, 2024
    Publication date: May 22, 2025
    Inventors: MASASHI NISHI, TSUTOMU NISHIDA, AKIHIRO MARUYAMA, NORIFUMI MURANAKA
  • Publication number: 20250138445
    Abstract: Provided is an electrophotographic apparatus having high positive chargeability even in an electrophotographic apparatus that simultaneously uses toner containing alumina particles as an external additive and a photosensitive member containing a polyarylate resin excellent in mechanical strength. In the electrophotographic apparatus, the electrophotographic photosensitive member includes a monolayer type photosensitive layer containing a charge generating material, a hole transporting material, an electron transporting material, and a binder resin, the photosensitive layer contains a polyarylate resin having a structural unit represented by the formula (1) and a structural unit represented by the formula (2) as the binder resin, the toner is toner containing toner particles, the toner particles each contain a toner base particle and an external additive adhering to a surface of the toner base particle, and the external additive contains at least aluminum oxide particles.
    Type: Application
    Filed: October 22, 2024
    Publication date: May 1, 2025
    Inventors: NORIFUMI MURANAKA, TSUTOMU NISHIDA, MASASHI NISHI, AKIHIRO MARUYAMA
  • Publication number: 20250138442
    Abstract: An electrophotographic apparatus including an electrophotographic photosensitive member, a charging unit that charges a surface of the electrophotographic photosensitive member, an exposing unit that irradiates the charged surface of the electrophotographic photosensitive member with light to form an electrostatic latent image on the surface of the electrophotographic photosensitive member, and a developing unit, which includes toner, and which develops the electrostatic latent image formed on the surface of the electrophotographic photosensitive member with the toner to form a toner image on the surface of the electrophotographic photosensitive member. The electrophotographic photosensitive member includes a monolayer type photosensitive layer containing a charge generating substance, a hole transporting substance, an electron transporting substance, and a binder resin.
    Type: Application
    Filed: October 23, 2024
    Publication date: May 1, 2025
    Inventors: AKIHIRO MARUYAMA, MASASHI NISHI, NORIFUMI MURANAKA, TSUTOMU NISHIDA
  • Publication number: 20240402626
    Abstract: An image-forming apparatus with strontium titanate used as an external additive for a toner is provided, wherein the image-forming apparatus is an electrophotographic apparatus that has the durability of an electrophotographic photosensitive member maintained and is superior in transferability even under low-temperature/low-humidity conditions. An electrophotographic apparatus is provided, the electrophotographic apparatus including: an electrophotographic photosensitive member having a surface layer containing a resin X as a binder resin; a charging unit; an exposing unit; a developing unit; and a transferring unit, wherein the toner contains strontium titanate as an external additive, and the resin X contains a structural unit represented by Formula (1).
    Type: Application
    Filed: May 30, 2024
    Publication date: December 5, 2024
    Inventors: NOBUHIRO NAKAMURA, FUMIYUKI HIYAMA, TSUTOMU NISHIDA, SHUNTARO WATANABE
  • Publication number: 20240361709
    Abstract: Provided is a process cartridge capable of suppressing the occurrence of a banding image that is detachably attachable onto a main body of an electrophotographic apparatus. A developing roller and a toner supply roller are configured to be rotated so that R represented by the following formula (E1) satisfies 1.2?R?1.5 and are configured so that a movement direction of a surface of the developing roller is opposite to a movement direction of a surface of the toner supply roller at a contact position with respect to the toner supply roller: R=VRS/VD Formula (E1) (in the formula (E1), VRS represents an absolute value of a peripheral speed [m/s] of the toner supply roller, and VD represents an absolute value of a peripheral speed [m/s] of the developing roller). An electrophotographic photosensitive member includes a surface layer containing a polyarylate resin including a structural unit represented by the following formula (A1).
    Type: Application
    Filed: April 25, 2024
    Publication date: October 31, 2024
    Inventors: CHIHARU AKIYAMA, KANAME WATARIGUCHI, TSUTOMU NISHIDA
  • Publication number: 20240361725
    Abstract: Provided is a process cartridge being detachably attachable onto a main body of an electrophotographic apparatus. The process cartridge includes an electrophotographic photosensitive member, a developing roller, and a toner-supplying roller. The developing roller and the toner-supplying roller are configured to be opposite to each other at a contact position between the developing roller and the toner-supplying roller, and to be rotated while R represented by the following formula (E1) satisfies 1.2?R?1.5: R=VRS/VD Formula (E1) (in the formula (E1), VRS represents an absolute value of a peripheral velocity [m/s] of the toner-suppling roller, and VD represents an absolute value of a peripheral velocity [m/s] of the developing roller). The electrophotographic photosensitive member includes a surface layer containing a polycarbonate resin including a structural unit represented by the formula (A1).
    Type: Application
    Filed: April 25, 2024
    Publication date: October 31, 2024
    Inventors: KANAME WATARIGUCHI, TSUTOMU NISHIDA, CHIHARU AKIYAMA
  • Publication number: 20240361724
    Abstract: Provided is a process cartridge being detachably attachable onto a main body of an electrophotographic apparatus. The process cartridge includes an electrophotographic photosensitive member, a developing roller, and a toner-supplying roller. The developing roller and the toner-supplying roller are rotated so as to satisfy a particular velocity ratio so that the surface of the developing roller and the surface of the toner-supplying roller are opposite to each other at a contact position therebetween. The surface of the developing roller is a surface of an elastic layer, and the toner-supplying roller includes a shaft body and a resin layer formed on an outer peripheral surface of the shaft body. The electrophotographic photosensitive member includes a surface layer containing a polyarylate resin including a structural unit represented by the following formula (A1) and a structural unit represented by the following formula (A2).
    Type: Application
    Filed: April 25, 2024
    Publication date: October 31, 2024
    Inventors: CHIHARU AKIYAMA, KANAME WATARIGUCHI, TSUTOMU NISHIDA
  • Publication number: 20240345496
    Abstract: Provided is an electrophotographic photosensitive member including in this order: a support; an undercoat layer, and a photosensitive layer, wherein the undercoat layer comprises at least one kind of polymer selected from the group consisting of: a polymer having a structural unit represented by the following formula (1); and a polymer having a structural unit represented by the following formula (2).
    Type: Application
    Filed: March 19, 2024
    Publication date: October 17, 2024
    Inventors: AKIHIRO MARUYAMA, MICHIYO SEKIYA, MASASHI NISHI, NANAMI KATO, TOMOHITO ISHIDA, TSUTOMU NISHIDA
  • Publication number: 20240201608
    Abstract: An electrophotographic photosensitive member includes a surface layer. The surface layer comprises a polycarbonate resin (?) and a polycarbonate resin (?). The polycarbonate resin (?) has a structural unit represented by a following formula (A) described herein and a structural unit represented by a following formula (B) described herein. The polycarbonate resin (?) has a structure having a dimethylsiloxane moiety.
    Type: Application
    Filed: November 15, 2023
    Publication date: June 20, 2024
    Inventors: AKIRA SAKAKIBARA, YUKA ISHIDUKA, DAISUKE MIURA, TSUTOMU NISHIDA, FUMIYUKI HIYAMA
  • Publication number: 20240201609
    Abstract: Provided is an electrophotographic photosensitive member in which streaky image damage can be suppressed throughout long-term use in a low-temperature and low-humidity environment. An electrophotographic photosensitive member having a surface layer comprising a polyarylate and a polycarbonate, wherein the polyarylate has at least one structural unit selected from the group consisting of a structural unit represented by the following formula (1-1), a structural unit represented by the following formula (1-2) and a structural unit represented by the following formula (1-3), and the polycarbonate has a structural unit represented by the following formula (2-1).
    Type: Application
    Filed: November 9, 2023
    Publication date: June 20, 2024
    Inventors: YUKA ISHIDUKA, FUMIYUKI HIYAMA, AKIRA SAKAKIBARA, TSUTOMU NISHIDA, DAISUKE MIURA
  • Publication number: 20240192616
    Abstract: Provided is a process cartridge integrally supporting an electrophotographic photosensitive member, a developing unit, and a cleaning unit, and being detachably attachable onto a main body of an electrophotographic apparatus. A surface layer of the electrophotographic photosensitive member comprises a polycarbonate resin having a structural unit represented by the formula (1), a structural unit represented by the formula (2), and a structural unit represented by the formula (3). Toner contains: a toner particle containing a resin; and an external additive. The external additive contains a particle of a silicon atom-containing compound, and a content ratio of the particle of the silicon atom-containing compound in the toner is 2.0 to 3.0 mass % with respect to a total mass of the toner. Also provided is an electrophotographic apparatus including the process cartridge.
    Type: Application
    Filed: November 16, 2023
    Publication date: June 13, 2024
    Inventors: FUMIYUKI HIYAMA, YUKA ISHIDUKA, AKIRA SAKAKIBARA, TSUTOMU NISHIDA, DAISUKE MIURA
  • Publication number: 20240168398
    Abstract: To provide an electrophotographic photosensitive member capable of satisfying both high durability and high sensitivity at a high level. An electrophotographic photosensitive member having a support, a charge generation layer formed on the support and a charge transport layer formed on the charge generation layer, the charge transport layer being a surface layer, in which the charge transport layer comprises a polyester resin having a structural unit represented by the following formula (1) and a charge-transporting compound represented by the following formula (HTM1).
    Type: Application
    Filed: October 19, 2023
    Publication date: May 23, 2024
    Inventors: TATSUYA YAMAAI, NOBUHIRO NAKAMURA, TSUTOMU NISHIDA, DAISUKE MIURA
  • 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