Patents by Inventor Kazuhisa Shirayama

Kazuhisa Shirayama 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: 20210141315
    Abstract: A magnetic carrier including a magnetic carrier particle having a magnetic core particle and a coating layer of an organosilicon polymer on a surface of the magnetic core particle, wherein the organosilicon polymer has the structure given by formula (T3) below; in 29Si-NMR measurement of the THF-insoluble matter of the organosilicon polymer, the ratio ST3 of the peak area for the structure given by formula (T3) to the total peak area for the organosilicon polymer is at least 0.05; and in the roughness curve measured on the magnetic carrier particle, the mean width (RSm) of the roughness curve elements of the magnetic carrier particle, and the ratio (?/RSm) to this RSm of the standard deviation ? of the width of the region where one period of a protrusion and a recess occurs, are in prescribed ranges. R—Si(O1/2)3??(T3) R in the formula represents a prescribed substituent.
    Type: Application
    Filed: November 9, 2020
    Publication date: May 13, 2021
    Inventors: Kentaro Kamae, Kazuhisa Shirayama, Takeshi Hashimoto, Takeshi Ohtsu, Hayato Ida
  • Patent number: 10969705
    Abstract: Provided is a two-component developer has a toner including a toner particle including a binder resin, and a magnetic carrier, wherein the binder resin includes a polymer A having a first monomer unit derived from a first polymerizable monomer, and a second monomer unit derived from a second polymerizable monomer different from the first polymerizable monomer, the first polymerizable monomer is a specific (meth)acrylic acid ester, a content and an SP value of the first and second monomer units in the polymer A fall within respective specific ranges, the magnetic carrier has a magnetic core and a coating resin of the surface of the magnetic core, the coating resin includes a polymer B having monomer units (a) and (b), each SP value of the monomer units (a) and (b) is a specific value.
    Type: Grant
    Filed: June 12, 2019
    Date of Patent: April 6, 2021
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kazuhisa Shirayama, Hayato Ida, Takeshi Hashimoto, Kentaro Kamae, Takashi Matsui
  • Patent number: 10859931
    Abstract: A toner having an inorganic fine particle and a toner particle containing a binder resin, wherein the binder resin contains a polymer A having a first monomer unit derived from a first polymerizable monomer and a second monomer unit derived from a second polymerizable monomer that is different from the first polymerizable monomer, the first polymerizable monomer is selected from the (meth)acrylic acid esters each having a C18-36 alkyl group, the content of the first monomer unit in the polymer A is within a specific range, the SP value of the first monomer unit and the SP value of the second monomer unit are in a specific relationship to one another, the inorganic fine particle is surface treated with a compound having an alkyl group, and the volume resistivity of the inorganic fine particle is within a specific range.
    Type: Grant
    Filed: June 12, 2019
    Date of Patent: December 8, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Takeshi Hashimoto, Kentaro Kamae, Kazuhisa Shirayama, Hayato Ida, Takashi Matsui
  • Patent number: 10768557
    Abstract: An intermediary transfer belt includes a base layer; an elastic layer laminated on or above the base layer and formed with a silicone rubber as an elastic member; an intermediary layer laminated on or above the elastic layer; and a surface layer laminated on or above the intermediary layer. The elastic layer is 60 degrees or less in JIS-A hardness and is 5 degrees or more in JIS-E hardness. The intermediary layer is 0.1 g/m2·24 h or more and 600 g/m2·24 h or less in water vapor permeability coefficient and is 1 ?m or more and 15 ?m or less in average thickness.
    Type: Grant
    Filed: December 17, 2019
    Date of Patent: September 8, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kaoru Okamoto, Kazuhisa Shirayama, Ryosuke Tsuruga, Yasutomo Tsuji
  • Publication number: 20200201209
    Abstract: An intermediary transfer belt includes a base layer; an elastic layer laminated on or above the base layer and formed with a silicone rubber as an elastic member; an intermediary layer laminated on or above the elastic layer; and a surface layer laminated on or above the intermediary layer. The elastic layer is 60 degrees or less in JIS-A hardness and is 5 degrees or more in JIS-E hardness. The intermediary layer is 0.1 g/m2·24 h or more and 600 g/m2·24 h or less in water vapor permeability coefficient and is 1 ?m or more and 15 ?m or less in average thickness.
    Type: Application
    Filed: December 17, 2019
    Publication date: June 25, 2020
    Inventors: Kaoru Okamoto, Kazuhisa Shirayama, Ryosuke Tsuruga, Yasutomo Tsuji
  • Patent number: 10656545
    Abstract: A toner has a toner particle including a binder resin, the binder resin includes a polymer A, the polymer A contains a first monomer unit derived from a first polymerizable monomer and a second monomer unit derived from a second polymerizable monomer, the first polymerizable monomer is selected from (meth)acrylic acid esters having an alkyl group having 18 to 36 carbon atoms, the content of the first monomer unit in the polymer A is 5.0 mol % to 60.0 mol %, the content of the second monomer unit in the polymer A is 20.0 mol % to 95.0 mol %, the SP value of the first monomer unit and the SP value of the second monomer unit satisfy a predetermined relationship, the polymer A includes a predetermined polyvalent metal, and the content of the polyvalent metal is 25 ppm to 500 ppm.
    Type: Grant
    Filed: June 12, 2019
    Date of Patent: May 19, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kentaro Kamae, Kazuhisa Shirayama, Takeshi Hashimoto, Hayato Ida, Takashi Matsui
  • Publication number: 20200019093
    Abstract: An intermediary transfer belt having surface resistivity ?s of 1×109 ?/square or more and volume resistivity ?v of 1×1012 ?·cm or less includes a thermoplastic resin material containing carbon black. The carbon black contained in the thermoplastic resin material has a weight ratio of 22.5-28.5 weight % and include first carbon black and second carbon black. The first carbon black of the carbon black contained in the thermoplastic resin material has a weight ratio of 50-90 weight % and dibutyl phthalate absorption of 93-127 ml/100 g, and the second carbon black of the carbon black contained in the thermoplastic resin material has a weight ratio of 10-50 weight % and dibutyl phthalate absorption of 36-79 ml/100 g.
    Type: Application
    Filed: July 10, 2019
    Publication date: January 16, 2020
    Inventors: Ryosuke Tsuruga, Toshiyuki Yoshida, Jun Ohira, Akeshi Asaka, Hiroto Sugimoto, Takanori Ueno, Koji Sato, Midai Suzuki, Atsushi Hori, Kaoru Okamoto, Megumi Uchino, Kazuhisa Shirayama, Naoto Kameyama, Kiyonori Soutome, Shigeo Kuroda, Akira Okano, Hiroshi Tominaga
  • Publication number: 20190384193
    Abstract: A toner having an inorganic fine particle and a toner particle containing a binder resin, wherein the binder resin contains a polymer A having a first monomer unit derived from a first polymerizable monomer and a second monomer unit derived from a second polymerizable monomer that is different from the first polymerizable monomer, the first polymerizable monomer is selected from the (meth)acrylic acid esters each having a C18-36 alkyl group, the content of the first monomer unit in the polymer A is within a specific range, the SP value of the first monomer unit and the SP value of the second monomer unit are in a specific relationship to one another, the inorganic fine particle is surface treated with a compound having an alkyl group, and the volume resistivity of the inorganic fine particle is within a specific range.
    Type: Application
    Filed: June 12, 2019
    Publication date: December 19, 2019
    Inventors: Takeshi Hashimoto, Kentaro Kamae, Kazuhisa Shirayama, Hayato Ida, Takashi Matsui
  • Publication number: 20190384202
    Abstract: Provided is a two-component developer has a toner including a toner particle including a binder resin, and a magnetic carrier, wherein the binder resin includes a polymer A having a first monomer unit derived from a first polymerizable monomer, and a second monomer unit derived from a second polymerizable monomer different from the first polymerizable monomer, the first polymerizable monomer is a specific (meth)acrylic acid ester, a content and an SP value of the first and second monomer units in the polymer A fall within respective specific ranges, the magnetic carrier has a magnetic core and a coating resin of the surface of the magnetic core, the coating resin includes a polymer B having monomer units (a) and (b), each SP value of the monomer units (a) and (b) is a specific value.
    Type: Application
    Filed: June 12, 2019
    Publication date: December 19, 2019
    Inventors: Kazuhisa Shirayama, Hayato Ida, Takeshi Hashimoto, Kentaro Kamae, Takashi Matsui
  • Publication number: 20190384196
    Abstract: A toner has a toner particle including a binder resin, the binder resin includes a polymer A, the polymer A contains a first monomer unit derived from a first polymerizable monomer and a second monomer unit derived from a second polymerizable monomer, the first polymerizable monomer is selected from (meth)acrylic acid esters having an alkyl group having 18 to 36 carbon atoms, the content of the first monomer unit in the polymer A is 5.0 mol % to 60.0 mol %, the content of the second monomer unit in the polymer A is 20.0 mol % to 95.0 mol %, the SP value of the first monomer unit and the SP value of the second monomer unit satisfy a predetermined relationship, the polymer A includes a predetermined polyvalent metal, and the content of the polyvalent metal is 25 ppm to 500 ppm.
    Type: Application
    Filed: June 12, 2019
    Publication date: December 19, 2019
    Inventors: Kentaro Kamae, Kazuhisa Shirayama, Takeshi Hashimoto, Hayato Ida, Takashi Matsui
  • Patent number: 9158214
    Abstract: There are provided an electrophotographic photosensitive member and an intermediate transfer member each having good lubricity and good cleaning property on its surface, a process cartridge and an electrophotographic apparatus each including the electrophotographic photosensitive member, and an electrophotographic apparatus including the intermediate transfer member. Therefore, a surface layer of the electrophotographic photosensitive member or intermediate transfer member of the present invention contains a matrix component and a rotatably-retained spherical particle that is not bound with the matrix component and is rotatably retained in a pore in the matrix component.
    Type: Grant
    Filed: May 30, 2012
    Date of Patent: October 13, 2015
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kimihiro Yoshimura, Yohei Miyauchi, Keiko Yamagishi, Kazuhisa Shirayama, Maho Hori
  • Patent number: 9104124
    Abstract: The present invention relates to an electrophotographic photosensitive member including a support and a photosensitive layer formed on the support. The electrophotographic photosensitive member has a surface layer containing a polyarylate resin and acicular inorganic fillers. The acicular inorganic fillers are basic and have a number-average aspect ratio of 5 to 50 and a Mohs hardness of 2 to 6.
    Type: Grant
    Filed: April 23, 2012
    Date of Patent: August 11, 2015
    Assignee: Canon Kabushiki Kaisha
    Inventors: Maho Hori, Kimihiro Yoshimura, Yohei Miyauchi, Kazuhisa Shirayama
  • Publication number: 20140113225
    Abstract: There are provided an electrophotographic photosensitive member and an intermediate transfer member each having good lubricity and good cleaning property on its surface, a process cartridge and an electrophotographic apparatus each including the electrophotographic photosensitive member, and an electrophotographic apparatus including the intermediate transfer member. Therefore, a surface layer of the electrophotographic photosensitive member or intermediate transfer member of the present invention contains a matrix component and a rotatably-retained spherical particle that is not bound with the matrix component and is rotatably retained in a pore in the matrix component.
    Type: Application
    Filed: May 30, 2012
    Publication date: April 24, 2014
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Kimihiro Yoshimura, Yohei Miyauchi, Keiko Yamagishi, Kazuhisa Shirayama, Maho Hori
  • Publication number: 20140051018
    Abstract: The present invention relates to an electrophotographic photosensitive member including a support and a photosensitive layer formed on the support. The electrophotographic photosensitive member has a surface layer containing a polyarylate resin and acicular inorganic fillers. The acicular inorganic fillers are basic and have a number-average aspect ratio of 5 to 50 and a Mohs hardness of 2 to 6.
    Type: Application
    Filed: April 23, 2012
    Publication date: February 20, 2014
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Maho Hori, Kimihiro Yoshimura, Yohei Miyauchi, Kazuhisa Shirayama
  • Publication number: 20140017605
    Abstract: There is provided a film having resistance to an increase in the friction coefficient resulting from wearing. The film has a first portion having hardness of 0.01 to 3 GPa and a second portion. The hardness ratio of the second portion to the first portion is of 1.2 to 30. The first portion and the second portion form a first surface portion and a second surface region of the film, respectively. Each of the first portion and the second portion extends to a depth of 75% or more of the thickness of the film. In a 1 mm×1 mm square region disposed on an arbitrary position of the surface of the film, the second surface region accounts for 10% to 80% by area of the square region, and the first surface region and the second surface region account for 50% or more by area of the square region.
    Type: Application
    Filed: April 5, 2012
    Publication date: January 16, 2014
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Kazuhisa Shirayama, Yohei Miyauchi, Kimihiro Yoshimura, Toshihiro Kikuchi