Patents by Inventor Yuichi Yajima

Yuichi Yajima 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: 9880478
    Abstract: Provided is a method of producing a toner including a toner particle, the method including: a granulation step of mixing a polymerizable monomer composition containing a polymerizable monomer and an aqueous medium to form a suspension of particles of the polymerizable monomer composition; and a polymerization step of polymerizing the polymerizable monomer in each of the particles of the polymerizable monomer composition in the presence of a metal phosphate containing aluminum as a metal element to provide the toner particle, the content ratio of aluminum in the metal phosphate containing aluminum being 1.0 mol % or more and 95.0 mol % or less with respect to all metal elements, the metal phosphate containing aluminum being obtained by adding an aluminum compound to the aqueous medium and/or the suspension.
    Type: Grant
    Filed: December 29, 2016
    Date of Patent: January 30, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Tsutomu Shimano, Kunihiko Nakamura, Kenta Kamikura, Yuichi Yajima, Kenji Ookubo, Dai Nozaki, Tohru Hiramatsu
  • Publication number: 20170199474
    Abstract: Provided is a method of producing a toner including a toner particle, the method including: a granulation step of mixing a polymerizable monomer composition containing a polymerizable monomer and an aqueous medium to form a suspension of particles of the polymerizable monomer composition; and a polymerization step of polymerizing the polymerizable monomer in each of the particles of the polymerizable monomer composition in the presence of a metal phosphate containing aluminum as a metal element to provide the toner particle, the content ratio of aluminum in the metal phosphate containing aluminum being 1.0 mol % or more and 95.0 mol % or less with respect to all metal elements, the metal phosphate containing aluminum being obtained by adding an aluminum compound to the aqueous medium and/or the suspension.
    Type: Application
    Filed: December 29, 2016
    Publication date: July 13, 2017
    Inventors: Tsutomu Shimano, Kunihiko Nakamura, Kenta Kamikura, Yuichi Yajima, Kenji Ookubo, Dai Nozaki, Tohru Hiramatsu
  • Patent number: 9658549
    Abstract: A toner having a toner particle including a binder resin, wherein the binder resin includes a styrene acrylic resin and a vinyl-modified crystalline polyester resin, the vinyl-modified crystalline polyester resin has a crystalline polyester segment having structures of following i) or a structure of following ii), i) at least two structures selected from the group consisting of a structure derived from an aliphatic dicarboxylic acid, a structure derived from an aliphatic diol and a structure derived from an aliphatic hydroxycarboxylic acid; ii) a structure derived from an aliphatic hydroxycarboxylic acid; and the vinyl-modified crystalline polyester resin has a specific modification rate.
    Type: Grant
    Filed: May 13, 2016
    Date of Patent: May 23, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Masatake Tanaka, Yoshihiro Nakagawa, Naoya Isono, Harumi Takada, Yuichi Yajima, Dai Nozaki
  • Publication number: 20160349640
    Abstract: A toner having a toner particle including a binder resin, wherein the binder resin includes a styrene acrylic resin and a vinyl-modified crystalline polyester resin, the vinyl-modified crystalline polyester resin has a crystalline polyester segment having structures of following i) or a structure of following ii), i) at least two structures selected from the group consisting of a structure derived from an aliphatic dicarboxylic acid, a structure derived from an aliphatic diol and a structure derived from an aliphatic hydroxycarboxylic acid; ii) a structure derived from an aliphatic hydroxycarboxylic acid; and the vinyl-modified crystalline polyester resin has a specific modification rate.
    Type: Application
    Filed: May 13, 2016
    Publication date: December 1, 2016
    Inventors: Masatake Tanaka, Yoshihiro Nakagawa, Naoya Isono, Harumi Takada, Yuichi Yajima, Dai Nozaki
  • Patent number: 8086160
    Abstract: A fixing roller has a base layer, a rubber layer formed on the base layer and a surface layer formed of a fluororesin tube, and a heater disposed inside the roller. The surface layer of the roller is formed by covering the fluororesin tube on the rubber layer in a condition where the fluororesin tube is pulled in a radial direction of the fluororesin tube, the fluororesin tube has an internal diameter less than an outer diameter of the roller and a thickness of 20 microns or smaller and a crystallization degree of the fluororesin tube being 50% or smaller. The roller is made by expanding the fluororesin tube is in a radial direction and drawing the fluororesin tube in a generatrix direction thereof, wherein a drawing ratio of the fluororesin tube in the drawing the fluororesin tube in the generatrix direction is 5% or smaller.
    Type: Grant
    Filed: December 3, 2008
    Date of Patent: December 27, 2011
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yuki Nishizawa, Ken Nakagawa, Takaaki Akamatsu, Shuuichi Tetsuno, Yuichi Yajima
  • Patent number: 7943281
    Abstract: In a black toner having at least a binder resin and an iron-titanium composite oxide as a colorant; the iron-titanium composite oxide is contained in a specific amount; the black toner has a specific weight average particle diameter and a specific saturation magnetization; the black toner has, in X-ray diffraction thereof, a maximum peak at 2?=from 32.5 to 33.1 degrees, having a half width of 0.25 degree or less. The black toner has, in a proportion of less than 30% by number, an iron-titanium composite oxide having, in a sectional photograph of the toner, a maximum frequency of linearity within the range where the linearity is smaller than 2.4 and having a linearity of 3.0 or more, in regard to the number frequency distribution of the linearity of the iron-titanium composite oxide.
    Type: Grant
    Filed: April 14, 2006
    Date of Patent: May 17, 2011
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takaaki Kaya, Yasukazu Ayaki, Shigeto Tamura, Yayoi Tazawa, Ryoichi Fujita, Yuichi Yajima
  • Publication number: 20090092426
    Abstract: A fixing apparatus, a roller for a fixing apparatus, and a flexible sleeve for a fixing apparatus are a roller for the fixing apparatus (1) having a rubber layer (1b) and a fluororesin tube as a surface layer (1c) covered thereon. A thickness of the fluororesin tube is 20 microns or smaller, and a crystallization degree of the fluororesin tube is 50% or smaller. Thus, in the roller for the fixing apparatus having the rubber layer on which the resin tube is covered as the surface layer, a crack does not occur in the fluororesin tube even if the fluororesin tube is made thin.
    Type: Application
    Filed: December 3, 2008
    Publication date: April 9, 2009
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Yuki Nishizawa, Ken Nakagawa, Takaaki Akamatsu, Shuuichi Tetsuno, Yuichi Yajima
  • Publication number: 20090011353
    Abstract: In a black toner having at least a binder resin and an iron-titanium composite oxide as a colorant; the iron-titanium composite oxide is contained in a specific amount; the black toner has a specific weight average particle diameter and a specific saturation magnetization; the black toner has, in X-ray diffraction thereof, a maximum peak at 2?=from 32.5 to 33.1 degrees, having a half width of 0.25 degree or less. The black toner has, in a proportion of less than 30% by number, an iron-titanium composite oxide having, in a sectional photograph of the toner, a maximum frequency of linearity within the range where the linearity is smaller than 2.4 and having a linearity of 3.0 or more, in regard to the number frequency distribution of the linearity of the iron-titanium composite oxide.
    Type: Application
    Filed: April 14, 2006
    Publication date: January 8, 2009
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Takaaki Kaya, Yasukazu Ayaki, Shigeto Tamura, Yayoi Tazawa, Ryoichi Fujita, Yuichi Yajima