Patents by Inventor Satoshi Otsuji

Satoshi Otsuji 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: 11294296
    Abstract: A toner comprising: a toner particle including a binder resin; and an external additive, wherein the external additive includes an external additive A which is silica fine particles and an external additive B which is a fatty acid metal salt, the external additive A has a specific particle diameter, a coverage ratio of a surface of the toner particle with the external additive A is from 60% to 80%, and where an average theoretical surface area obtained from a number average particle diameter, a particle size distribution and a true density of the toner particle is denoted by C (m2/g), an amount of the external additive B is denoted by D (parts by mass) and a coverage ratio of the surface of the toner particle with the external additive B is denoted by E (%), following formulas are satisfied: 0.05?D/C?2.00 E/(D/C)?50.0.
    Type: Grant
    Filed: June 25, 2020
    Date of Patent: April 5, 2022
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Hidekazu Fumita, Noriyoshi Umeda, Tomonori Matsunaga, Satoshi Otsuji
  • Patent number: 10976678
    Abstract: Provided is a toner including a toner particle containing a binder resin, and an external additive, wherein the external additive contains an external additive A and an external additive B, the external additive A is an organosilicon polymer fine particle, the number-average particle diameter of primary particles of the organosilicon polymer fine particle is from 30 to 300 nm, the external additive B is a silica fine particle, the number-average particle diameter of primary particles of the silica fine particle is from 100 to 300 nm, the fixing rate of the external additive A to the toner particle according to a water washing method is less than 30%, and the fixing rate of the external additive B to the toner particle according to the washing method is at least 30%.
    Type: Grant
    Filed: December 27, 2019
    Date of Patent: April 13, 2021
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kentaro Yamawaki, Shohei Kototani, Noriyoshi Umeda, Tomonori Matsunaga, Shohei Tsuda, Satoshi Otsuji
  • Publication number: 20210003934
    Abstract: A toner comprising: a toner particle including a binder resin; and an external additive, wherein the external additive includes an external additive A which is silica fine particles and an external additive B which is a fatty acid metal salt, the external additive A has a specific particle diameter, a coverage ratio of a surface of the toner particle with the external additive A is from 60% to 80%, and where an average theoretical surface area obtained from a number average particle diameter, a particle size distribution and a true density of the toner particle is denoted by C (m2/g), an amount of the external additive B is denoted by D (parts by mass) and a coverage ratio of the surface of the toner particle with the external additive B is denoted by E (%), following formulas are satisfied: 0.05?D/C?2.00 E/(D/C)?50.0.
    Type: Application
    Filed: June 25, 2020
    Publication date: January 7, 2021
    Inventors: Hidekazu Fumita, Noriyoshi Umeda, Tomonori Matsunaga, Satoshi Otsuji
  • Patent number: 10845721
    Abstract: A toner has a toner particle that has a binder resin and a release agent, wherein when the temperature when G?=1.0×105 Pa in a dynamic viscoelastic measurement on the toner is denoted by Ta, and the glass transition temperature in a differential scanning calorimetric measurement on the toner is denoted by Tg, the Ta and the Tg satisfy the following formulas: 40° C.?Tg?70° C., 60° C.?Ta?90° C., and 0° C.?Ta?Tg?35° C.; and the toner has a storage elastic modulus G? having a minimum value in the range from 110° C. to 150° C. in a dynamic viscoelastic measurement on the toner.
    Type: Grant
    Filed: October 14, 2019
    Date of Patent: November 24, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Masatake Tanaka, Tsuneyoshi Tominaga, Noriyoshi Umeda, Satoshi Otsuji, Shinsuke Mochizuki
  • Patent number: 10809639
    Abstract: A toner having a toner particle including a binder resin and a wax, wherein the wax includes a specific diester compound; a proportion As of an area occupied by the wax in a region from a surface of the toner particle to 0.5 ?m is 15.0% or less; wax domains are observed in the cross section of the toner particle, and an average number of the domains per cross section of one toner particle is from 10 to 2000; when a mass concentration of a polyvalent metal element in the toner particle determined by fluorescent X-ray analysis is denoted by Mi (ppm), Mi is from 3.5 ppm to 1100 ppm; and when a mass concentration of a polyvalent metal element in the toner particle determined by X-ray photoelectron spectroscopy is denoted by Ms (ppm), Mi>Ms.
    Type: Grant
    Filed: October 31, 2019
    Date of Patent: October 20, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kentaro Yamawaki, Satoshi Otsuji, Masamichi Sato, Hidekazu Fumita
  • Patent number: 10747130
    Abstract: Provided is a process cartridge including: an electrophotographic photoreceptor; a charging unit configured to charge the electrophotographic photoreceptor through abutment against the electrophotographic photoreceptor; a developing unit configured to develop an electrostatic latent image formed on the electrophotographic photoreceptor with a toner to form a toner image; and a cleaning unit configured to remove the toner on the electrophotographic photoreceptor by bringing a blade into abutment against the electrophotographic photoreceptor, wherein the toner includes a toner base containing a coloring agent and a binder resin, and has a surface layer containing an organosilicon polymer having a specific sticking ratio to a toner base, and wherein the electrophotographic photoreceptor includes a supporting member and a surface layer, and the surface layer has a specific universal hardness value and a specific elastic deformation ratio (We).
    Type: Grant
    Filed: May 28, 2019
    Date of Patent: August 18, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Atsushi Okuda, Tsutomu Nishida, Yuka Ishiduka, Nobuhiro Nakamura, Hiroyuki Watanabe, Hideharu Shimozawa, Satoshi Otsuji, Kentaro Yamawaki, Daisuke Miura
  • Publication number: 20200209766
    Abstract: Provided is a toner including a toner particle containing a binder resin, and an external additive, wherein the external additive contains an external additive A and an external additive B, the external additive A is an organosilicon polymer fine particle, the number-average particle diameter of primary particles of the organosilicon polymer fine particle is from 30 to 300 nm, the external additive B is a silica fine particle, the number-average particle diameter of primary particles of the silica fine particle is from 100 to 300 nm, the fixing rate of the external additive A to the toner particle according to a water washing method is less than 30%, and the fixing rate of the external additive B to the toner particle according to the washing method is at least 30%.
    Type: Application
    Filed: December 27, 2019
    Publication date: July 2, 2020
    Inventors: Kentaro Yamawaki, Shohei Kototani, Noriyoshi Umeda, Tomonori Matsunaga, Shohei Tsuda, Satoshi Otsuji
  • Publication number: 20200142329
    Abstract: A toner having a toner particle including a binder resin and a wax, wherein the wax includes a specific diester compound; a proportion As of an area occupied by the wax in a region from a surface of the toner particle to 0.5 ?m is 15.0% or less; wax domains are observed in the cross section of the toner particle, and an average number of the domains per cross section of one toner particle is from 10 to 2000; when a mass concentration of a polyvalent metal element in the toner particle determined by fluorescent X-ray analysis is denoted by Mi (ppm), Mi is from 3.5 ppm to 1100 ppm; and when a mass concentration of a polyvalent metal element in the toner particle determined by X-ray photoelectron spectroscopy is denoted by Ms (ppm), Mi>Ms.
    Type: Application
    Filed: October 31, 2019
    Publication date: May 7, 2020
    Inventors: Kentaro Yamawaki, Satoshi Otsuji, Masamichi Sato, Hidekazu Fumita
  • Publication number: 20200124999
    Abstract: A toner has a toner particle that has a binder resin and a release agent, wherein when the temperature when G?=1.0×105 Pa in a dynamic viscoelastic measurement on the toner is denoted by Ta, and the glass transition temperature in a differential scanning calorimetric measurement on the toner is denoted by Tg, the Ta and the Tg satisfy the following formulas: 40° C.?Tg?70° C., 60° C.?Ta?90° C., and 0° C.?Ta?Tg?35° C.; and the toner has a storage elastic modulus G? having a minimum value in the range from 110° C. to 150° C. in a dynamic viscoelastic measurement on the toner.
    Type: Application
    Filed: October 14, 2019
    Publication date: April 23, 2020
    Inventors: Masatake Tanaka, Tsuneyoshi Tominaga, Noriyoshi Umeda, Satoshi Otsuji, Shinsuke Mochizuki
  • Publication number: 20190369512
    Abstract: Provided is a process cartridge including: an electrophotographic photoreceptor; a charging unit configured to charge the electrophotographic photoreceptor through abutment against the electrophotographic photoreceptor; a developing unit configured to develop an electrostatic latent image formed on the electrophotographic photoreceptor with a toner to form a toner image; and a cleaning unit configured to remove the toner on the electrophotographic photoreceptor by bringing a blade into abutment against the electrophotographic photoreceptor, wherein the toner includes a toner base containing a coloring agent and a binder resin, and has a surface layer containing an organosilicon polymer having a specific sticking ratio to a toner base, and wherein the electrophotographic photoreceptor includes a supporting member and a surface layer, and the surface layer has a specific universal hardness value and a specific elastic deformation ratio (We).
    Type: Application
    Filed: May 28, 2019
    Publication date: December 5, 2019
    Inventors: Atsushi Okuda, Tsutomu Nishida, Yuka Ishiduka, Nobuhiro Nakamura, Hiroyuki Watanabe, Hideharu Shimozawa, Satoshi Otsuji, Kentaro Yamawaki, Daisuke Miura
  • Publication number: 20190369529
    Abstract: Provided is an image forming apparatus capable of forming a high quality electrophotographic image. The image forming apparatus includes toner in which an organosilicon polymer is stuck to a toner base at a predetermined sticking ratio, an electrophotographic photoreceptor having a surface layer having a predetermined hardness and a predetermined elastic deformation ratio, and an intermediate transfer body having a surface having a predetermined hardness, and also includes a unit that provides a circumferential velocity difference between the electrophotographic photoreceptor and the intermediate transfer body.
    Type: Application
    Filed: May 28, 2019
    Publication date: December 5, 2019
    Inventors: Yasutaka Yagi, Satoshi Otsuji, Hidekazu Fumita, Masatake Tanaka, Kentaro Yamawaki, Atsushi Okuda, Tsutomu Nishida