Patents by Inventor Kenichi Mashiko

Kenichi Mashiko 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: 10915035
    Abstract: A carrier for developing an electrostatic latent image includes a core material particle and a resin layer covering a surface of the core material particle. The resin layer includes a resin and at least one kind of a fine particle. At least one kind of the fine particles includes a chargeable fine particle. The chargeable fine particle has a long diameter of 400 to 900 nm. The chargeable fine particle has a shape factor SF-1 of 160 to 250.
    Type: Grant
    Filed: May 26, 2017
    Date of Patent: February 9, 2021
    Assignee: Ricoh Company, Ltd.
    Inventors: Haruki Murata, Hiroyuki Kishida, Toyoaki Tano, Kenichi Mashiko, Masato Taikoji, Mariko Takii, Yoshihiro Murasawa
  • Publication number: 20200319571
    Abstract: An electrophotographic developer is provided. The electrophotographic developer comprises a toner and a carrier. The toner contains alumina particles. The carrier comprises a core particle and a resin layer coating a surface of the core particle. The carrier has a volume average particle diameter (Dv) of from 45 to 70 ?m and a bulk density of from 2.1 to 2.5 g/cm3.
    Type: Application
    Filed: March 31, 2020
    Publication date: October 8, 2020
    Inventors: Kento TAKEUCHI, Yutaka MAKIBE, Kenichi MASHIKO, Masato TAIKOJI, Kei NIWAYAMA
  • Publication number: 20200183297
    Abstract: A carrier for developing an electrostatic latent image includes a core material particle and a resin layer covering a surface of the core material particle. The resin layer includes a resin and at least one kind of a fine particle. At least one kind of the fine particles includes a chargeable fine particle. The chargeable fine particle has a long diameter of 400 to 900 nm. The chargeable fine particle has a shape factor SF-1 of 160 to 250.
    Type: Application
    Filed: May 26, 2017
    Publication date: June 11, 2020
    Inventors: Haruki MURATA, Hiroyuki KISHIDA, Toyoaki TANO, Kenichi MASHIKO, Masato TAIKOJI, Mariko TAKII, Yoshihiro MURASAWA
  • Patent number: 10234783
    Abstract: A carrier including a resin layer including at least one kind of particles, wherein the at least one kind of the particles are particles of barium sulfate, wherein an amount of Ba detected is 0.3 atomic % or greater in a Ba analysis through X-ray photoelectron spectroscopy (XPS) of the carrier, and wherein circle-equivalent diameters of the particles of the barium sulfate are 400 nm or greater but 900 nm or smaller.
    Type: Grant
    Filed: April 28, 2016
    Date of Patent: March 19, 2019
    Assignee: Ricoh Company, Ltd.
    Inventors: Koichi Sakata, Tohru Suganuma, Shohichi Sugimoto, Hiroshi Tohmatsu, Hiroyuki Kishida, Kenichi Mashiko, Toyoaki Tano
  • Patent number: 10197948
    Abstract: A developing device, including: a developer containing toner and carrier; and developer bearer configured to have surface thereof bear the developer and endlessly move, and to develop latent image over surface of latent image bearer by supplying toner in developer to latent image in developing region facing the latent image bearer, wherein carrier contains fine particles, value X in volume resistivity R (=10X) (?·cm) of carrier is 11.5-16.0, developer bearer includes: magnetic field generating unit including a plurality of magnetic poles; and developing sleeve having a cylindrical shape enclosing magnetic field generating unit, and configured to bear developer over outer circumferential surface of cylindrical shape by magnetic force of the magnetic field generating unit and perform surface moving by rotating relative to developing device body, and developing device includes developing sleeve voltage applying unit configured to apply AC component-containing voltage to developing sleeve.
    Type: Grant
    Filed: August 31, 2015
    Date of Patent: February 5, 2019
    Assignee: Ricoh Company, Ltd.
    Inventors: Hitoshi Iwatsuki, Koichi Sakata, Hiroshi Tohmatsu, Toyoaki Tano, Kenichi Mashiko, Mariko Takii, Hiroyuki Kishida, Yoshihiro Murasawa, Keinosuke Kondoh, Toshio Koike, Yutaka Takahashi
  • Patent number: 10067438
    Abstract: Provided is an electrostatic latent image developing white toner, including: a white toner including at least a binder resin, a white pigment, and a release agent; and a magnetic carrier including at least a core material, and a coating layer coating the core material and made of a coating resin and conductive particles, wherein Ra of the magnetic carrier is in a range of from 0.50 ?m to 1.00 ?m, and a bulk density of the magnetic carrier is in a range of from 2.08 g/cm3 to 2.24 g/cm3.
    Type: Grant
    Filed: September 29, 2015
    Date of Patent: September 4, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshihiro Murasawa, Hiroshi Tohmatsu, Hitoshi Iwatsuki, Mariko Takii, Koichi Sakata, Hiroyuki Kishida, Toyoaki Tano, Kenichi Mashiko
  • Patent number: 10054868
    Abstract: A carrier includes a core and a covering layer covering the core and including at least carbon black and a filler. The maximum height Ry of the surface of the carrier is from 4.0 ?m to 5.0 ?m.
    Type: Grant
    Filed: October 21, 2016
    Date of Patent: August 21, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroyuki Kishida, Kenichi Mashiko, Mariko Takii, Yoshihiro Murasawa, Haruki Murata
  • Patent number: 9989874
    Abstract: A carrier for developing electrostatic latent images is provided. The carrier includes a magnetic core particle and a resin layer coating a surface of the magnetic core particle. The resin layer includes a particulate material A having a volume average particle diameter (a) and a particulate material B having a volume average particle diameter (b). The volume average particle diameter (a) of the particulate material A is the largest among volume average particle diameters of all particulate materials included in the resin layer, and an inequation 100?(a)/(b)?5 is satisfied. The particulate material A is barium sulfate.
    Type: Grant
    Filed: March 3, 2017
    Date of Patent: June 5, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshihiro Murasawa, Toyoaki Tano, Hiroyuki Kishida, Masato Taikoji, Kenichi Mashiko, Mariko Takii, Haruki Murata
  • Publication number: 20180120724
    Abstract: A carrier including a resin layer including at least one kind of particles, wherein the at least one kind of the particles are particles of barium sulfate, wherein an amount of Ba detected is 0.3 atomic % or greater in a Ba analysis through X-ray photo-electron spectroscopy (XPS) of the carrier, and wherein circle-equivalent diameters of the particles of the barium sulfate are 400 nm or greater but 900 nm or smaller.
    Type: Application
    Filed: April 28, 2016
    Publication date: May 3, 2018
    Inventors: Koichi SAKATA, Tohru SUGANUMA, Shohichi SUGIMOTO, Hiroshi TOHMATSU, Hiroyuki KISHIDA, Kenichi MASHIKO, Toyoaki TANO
  • Publication number: 20170329247
    Abstract: Provided is an electrostatic latent image developing white toner, including: a white toner including at least a binder resin, a white pigment, and a release agent; and a magnetic carrier including at least a core material, and a coating layer coating the core material and made of a coating resin and conductive particles, wherein Ra of the magnetic carrier is in a range of from 0.50 ?m to 1.00 ?m, and a bulk density of the magnetic carrier is in a range of from 2.08 g/cm3 to 2.24 g/cm3.
    Type: Application
    Filed: September 29, 2015
    Publication date: November 16, 2017
    Inventors: Yoshihiro MURASAWA, Hiroshi TOHMATSU, Hitoshi IWATSUKI, Mariko TAKII, Koichi SAKATA, Hiroyuki KISHIDA, Toyoaki TANO, Kenichi MASHIKO
  • Patent number: 9791808
    Abstract: The surface layer of an intermediate transfer belt has a concavo-convex pattern formed thereon by spherical resin particles which are independently embedded in the layer so that the embedment rate in the thickness direction of the layer is higher than 50% but lower than 100%.
    Type: Grant
    Filed: January 17, 2011
    Date of Patent: October 17, 2017
    Assignee: RICOH COMPANY, LTD.
    Inventors: Jun Aoto, Hidetaka Kubo, Kenichi Mashiko, Sayaka Katoh, Shinichi Nitta, Shigeo Oonuma
  • Publication number: 20170269497
    Abstract: A carrier for developing electrostatic latent images is provided. The carrier includes a magnetic core particle and a resin layer coating a surface of the magnetic core particle. The resin layer includes a particulate material A having a volume average particle diameter (a) and a particulate material B having a volume average particle diameter (b). The volume average particle diameter (a) of the particulate material A is the largest among volume average particle diameters of all particulate materials included in the resin layer, and an inequation 100?(a)/(b)?5 is satisfied. The particulate material A is barium sulfate.
    Type: Application
    Filed: March 3, 2017
    Publication date: September 21, 2017
    Inventors: Yoshihiro MURASAWA, Toyoaki TANO, Hiroyuki KISHIDA, Masato TAIKOJI, Kenichi MASHIKO, Mariko TAKII, Haruki MURATA
  • Publication number: 20170248871
    Abstract: A developing device, including: a developer containing toner and carrier; and developer bearer configured to have surface thereof bear the developer and endlessly move, and to develop latent image over surface of latent image bearer by supplying toner in developer to latent image in developing region facing the latent image bearer, wherein carrier contains fine particles, value X in volume resistivity R (=10X) (?·cm) of carrier is 11.5-16.0, developer bearer includes: magnetic field generating unit including a plurality of magnetic poles; and developing sleeve having a cylindrical shape enclosing magnetic field generating unit, and configured to bear developer over outer circumferential surface of cylindrical shape by magnetic force of the magnetic field generating unit and perform surface moving by rotating relative to developing device body, and developing device includes developing sleeve voltage applying unit configured to apply AC component-containing voltage to developing sleeve.
    Type: Application
    Filed: August 31, 2015
    Publication date: August 31, 2017
    Inventors: Hitoshi IWATSUKI, Koichi SAKATA, Hiroshi TOHMATSU, Toyoaki TANO, Kenichi MASHIKO, Mariko TAKII, Hiroyuki KISHIDA, Yoshihiro MURASAWA, Keinosuke KONDOH, Toshio KOIKE, Yutaka TAKAHASHI
  • Publication number: 20170153563
    Abstract: A carrier includes a core and a covering layer covering the core and including at least carbon black and a filler. The maximum height Ry of the surface of the carrier is from 4.0 ?m to 5.0 ?m.
    Type: Application
    Filed: October 21, 2016
    Publication date: June 1, 2017
    Inventors: Hiroyuki KISHIDA, Kenichi MASHIKO, Mariko TAKll, Yoshihiro MURASAWA, Haruki MURATA
  • Patent number: 9298119
    Abstract: A carrier is provided. The carrier includes a particulate magnetic core, and a cover layer located on the surface of the particulate magnetic core and including a resin and a filler. When determined from observation of cross-section of the carrier, the shape factor SF2 of the carrier is from 120 to 160, the ratio of the average domain diameter of the particulate magnetic core to the number average particle diameter of the filler is from 1:1 to 1:0.003, and the area ratio of the filler in the cover layer is from 30 to 85%.
    Type: Grant
    Filed: January 29, 2014
    Date of Patent: March 29, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Shigenori Yaguchi, Koichi Sakata, Hitoshi Iwatsuki, Toyoaki Tano, Hiroyuki Kishida, Kenichi Mashiko, Hiroshi Tohmatsu
  • Patent number: 9261817
    Abstract: A replenishing developer housing container includes: a container body housing a replenishing developer; a conveying portion; a pipe receiving port; and an uplifting portion. The replenishing developer contains a toner and a carrier. The container body includes a protruding portion protruding from a container body interior side of the container opening portion toward one end of the container body and a curving portion curving so as to conform to the protruding portion. The uplifting portion includes an uplifting wall surface extending from an internal wall surface of the container body toward the protruding portion. When the replenishing developer housing container is mounted on the replenishing developer conveying device, the protruding portion is present between the curving portion and the replenishing developer receiving port of a conveying pipe being inserted.
    Type: Grant
    Filed: May 16, 2014
    Date of Patent: February 16, 2016
    Assignee: RICOH COMPANY, LTD.
    Inventors: Hitoshi Iwatsuki, Shigenori Yaguchi, Hiroshi Tohmatsu, Toyoaki Tano, Hiroyuki Kishida, Kenichi Mashiko, Koichi Sakata, Hiroshi Hosokawa, Shunji Katoh, Shinji Tamaki, Hiroshi Ikeguchi, Kenji Kikuchi, Michiharu Suzuki
  • Patent number: 9229347
    Abstract: A carrier for use in a two-component developer for developing an electrostatic latent image is provided. The carrier includes a particulate magnetic core; and a cover layer located on a surface of the particulate magnetic core and including a resin and a particulate electroconductive material. The carrier has a BET specific surface area of from 0.8 to 1.6 m2/g.
    Type: Grant
    Filed: December 16, 2013
    Date of Patent: January 5, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroyuki Kishida, Shigenori Yaguchi, Hiroshi Tohmatsu, Koichi Sakata, Hitoshi Iwatsuki, Toyoaki Tano, Kenichi Mashiko
  • Patent number: 9223256
    Abstract: An intermediate transfer belt including a base layer, and an elastic layer on the base layer containing spherical particles on a surface thereof and containing an elastic layer ingredient, wherein the elastic layer contains a fatty acid in an amount of 0.001 parts by mass to 0.040 parts by mass relative to 100 parts by mass of the elastic layer ingredient.
    Type: Grant
    Filed: September 12, 2013
    Date of Patent: December 29, 2015
    Assignee: RICOH COMPANY, LTD.
    Inventors: Sayaka Katoh, Jun Aoto, Kenichi Mashiko, Shinichi Nitta, Atsuo Hirai
  • Patent number: 9063475
    Abstract: To provide an intermediate transfer belt for use in an electrophotographic apparatus, including as an outermost surface thereof: uniform convex regions formed by aligning independent spherical resin particles in a surface direction; and depressed regions formed of a lubricant layer which respectively lie between the convex regions.
    Type: Grant
    Filed: May 17, 2011
    Date of Patent: June 23, 2015
    Assignee: RICOH COMPANY, LTD.
    Inventors: Jun Aoto, Hidetaka Kubo, Kenichi Mashiko, Sayaka Katoh, Shinichi Nitta
  • Patent number: 8934821
    Abstract: To provide a belt for an image forming apparatus, which contains: a base layer; an elastic layer; and spherical particles, wherein the belt for an image forming apparatus is provided across a plurality of rollers of the image forming apparatus to rotate, wherein the belt for an image forming apparatus has a laminate structure where at least the base layer and the elastic layer are provided in this order, wherein the spherical particles are partially embedded in an exposed surface of the elastic layer, and wherein, relative to a width direction of the belt for an image forming apparatus, a thickness of an edge portion of the belt for an image forming apparatus is 50% to 95% of a thickness of a center portion of the belt for an image forming apparatus, and an edge curling amount of the belt is 4 mm or less.
    Type: Grant
    Filed: November 15, 2012
    Date of Patent: January 13, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Hidetaka Kubo, Jun Aoto, Kenichi Mashiko, Sayaka Katoh, Daisuke Aoki