Patents by Inventor Masatake Tanaka

Masatake Tanaka 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: 10976679
    Abstract: A toner containing: a toner particle that contains a binder resin and an external additive, wherein the external additive contains an organosilicon polymer fine particle, the binder resin contains an amorphous resin and a crystalline polyester resin, a content of the crystalline polyester resin in the binder resin is from 5 to 30 mass %, and the crystalline polyester resin contains from 5 to 25 mass % of a component having a molecular weight of not more than 2,500.
    Type: Grant
    Filed: December 27, 2019
    Date of Patent: April 13, 2021
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Masatake Tanaka, Taiji Katsura, Masamichi Sato, Shohei Kototani, Kentaro Yamawaki, Tsuneyoshi Tominaga
  • Patent number: 10942466
    Abstract: A toner including a toner particle containing a binder resin and an external additive, wherein the toner particle contains a polyvalent metal compound, the polyvalent metal compound is at least one selected from the group consisting of aluminum compounds, iron compounds and magnesium compounds, a content of a metal element derived from the polyvalent metal compound in the toner particle is from 0.080 to 20.000 ?mol/g, the external additive contains an organosilicon polymer particle having a hydroxyl group, a ratio of a number-average particle diameter of the organosilicon polymer particle to a number-average particle diameter of the toner particle is from 0.0160 to 0.0650, and a content of the organosilicon polymer particle is at least 0.10 mass parts per 100.00 mass parts of the toner particle.
    Type: Grant
    Filed: December 27, 2019
    Date of Patent: March 9, 2021
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Tsuneyoshi Tominaga, Masatake Tanaka, Taiji Katsura, Masamichi Sato, Shohei Kototani, Kentaro Yamawaki
  • Publication number: 20210003932
    Abstract: A toner including a toner particle including a binder resin, wherein fine particles A and B are present on a surface of the toner particle; the fine particles A are a fatty acid metal salt; the fine particles B have a specific volume resistivity; an average theoretical surface area of the toner particle, an amount of the fine particles A, and a coverage ratio of the toner particle surface by the fine particles A satisfy a specific relationship; the amount of the fine particles B is in a specific range; and a proportion F of an area occupied by a part of the fine particles B embedded in a surface vicinity region of the toner in a total area occupied by the fine particles B present in a cross section of one particle of the toner is 50% by area or more.
    Type: Application
    Filed: June 25, 2020
    Publication date: January 7, 2021
    Inventors: Shohei Tsuda, Tsuneyoshi Tominaga, Masatake Tanaka, Taiji Katsura, Masamichi Sato
  • 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
  • Publication number: 20200209773
    Abstract: A toner including a toner particle containing a binder resin and an external additive, wherein the toner particle contains a polyvalent metal compound, the polyvalent metal compound is at least one selected from the group consisting of aluminum compounds, iron compounds and magnesium compounds, a content of a metal element derived from the polyvalent metal compound in the toner particle is from 0.080 to 20.000 ?mol/g, the external additive contains an organosilicon polymer particle having a hydroxyl group, a ratio of a number-average particle diameter of the organosilicon polymer particle to a number-average particle diameter of the toner particle is from 0.0160 to 0.0650, and a content of the organosilicon polymer particle is at least 0.10 mass parts per 100.00 mass parts of the toner particle.
    Type: Application
    Filed: December 27, 2019
    Publication date: July 2, 2020
    Inventors: Tsuneyoshi Tominaga, Masatake Tanaka, Taiji Katsura, Masamichi Sato, Shohei Kototani, Kentaro Yamawaki
  • Publication number: 20200209774
    Abstract: Provided is a toner including a toner particle and an external additive, wherein the external additive includes a composite particle including a hydrotalcite particle covered on the surface with an organosilicon polymer fine particle, a coverage ratio of the hydrotalcite particle surface by the organosilicon polymer fine particle is from 1% to 50%, and given A (nm) as the number-average particle diameter of the primary particles of the organosilicon polymer fine particle and B (nm) as the number-average particle diameter of the primary particles of the hydrotalcite particle, the toner satisfies the following formula (I) and formula (II): A<B??(I) 20?A?350??(II).
    Type: Application
    Filed: December 27, 2019
    Publication date: July 2, 2020
    Inventors: Taiji Katsura, Masamichi Sato, Shohei Kototani, Kentaro Yamawaki, Tsuneyoshi Tominaga, Masatake Tanaka
  • Publication number: 20200209775
    Abstract: A toner containing: a toner particle that contains a binder resin and an external additive, wherein the external additive contains an organosilicon polymer fine particle, the binder resin contains an amorphous resin and a crystalline polyester resin, a content of the crystalline polyester resin in the binder resin is from 5 to 30 mass %, and the crystalline polyester resin contains from 5 to 25 mass % of a component having a molecular weight of not more than 2,500.
    Type: Application
    Filed: December 27, 2019
    Publication date: July 2, 2020
    Inventors: Masatake Tanaka, Taiji Katsura, Masamichi Sato, Shohei Kototani, Kentaro Yamawaki, Tsuneyoshi Tominaga
  • Publication number: 20200209767
    Abstract: A toner including a toner particle containing a binder resin and an external additive, wherein the external additive contains composite particles of an organosilicon polymer fine particle and a fatty acid metal salt.
    Type: Application
    Filed: December 27, 2019
    Publication date: July 2, 2020
    Inventors: Masamichi Sato, Shohei Kototani, Kentaro Yamawaki, Tsuneyoshi Tominaga, Masatake Tanaka, Taiji Katsura
  • Publication number: 20200209776
    Abstract: A toner including a toner particle containing a binder resin, and an external additive, wherein the external additive contains an organosilicon polymer fine particle, the organosilicon polymer has a structure represented by at least one selected from the group consisting of RaSiO3/2 and Rb2SiO2/2 (wherein Ra and Rb represent organic groups), and in the number particle size distribution of the toner as measured within a particle size range of from 2 to 60 ?m, the number-average particle diameter T-D50n at which the accumulation from the smallest diameter is 50% is from 6 to 12 ?m, the number ratio of toner 4 ?m or less in size is from 2% to 5% of the total toner, and the number ratio of toner 3 ?m or less in size as a percentage of the total toner 4 ?m or less in size is from 25% to 50%.
    Type: Application
    Filed: December 27, 2019
    Publication date: July 2, 2020
    Inventors: Shohei Kototani, Kentaro Yamawaki, Tsuneyoshi Tominaga, Masatake Tanaka, Taiji Katsura, Masamichi Sato
  • 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: 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
  • Patent number: 10054866
    Abstract: A toner having a toner particle containing a binder resin and a crystalline material, wherein when “a” is an endothermic quantity deriving from the crystalline material in a DSC of the toner and “b” is an endothermic quantity deriving from the crystalline material in a DSC of the toner that has been held for 10 hours in an environment with a temperature of 55° C. and a humidity of 8% RH, the “a” and “b” satisfy a relationship a/b?0.85; in a dynamic viscoelastic measurement of a non-melt-molded pellet of the toner, the toner has a temperature range A for which G??1×105 Pa and tan ?<1 are satisfied; and in a dynamic viscoelastic measurement of a melt-molded pellet of the toner, the toner has a temperature range B for which tan ?>1 is satisfied within the temperature range A.
    Type: Grant
    Filed: April 13, 2017
    Date of Patent: August 21, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Masatake Tanaka, Nobuhisa Abe, Hidekazu Fumita, Masashi Kawamura, Shiro Kuroki, Kenji Ookuba
  • Patent number: 9958801
    Abstract: Provided is a toner including a toner particle containing a graft polymer, in which: the graft polymer has a crystalline polyester segment and an amorphous vinyl polymer segment; the crystalline polyester segment has a unit derived from a specific monomer (a) and a unit derived from a specific monomer (b); a content X (mol %) of the unit derived from the monomer (b) calculated from a specific formula is 1.0 mol % or more and 24 mol % or less; and a melting point of the graft polymer is 50° C. or more and 85° C. or less.
    Type: Grant
    Filed: May 11, 2016
    Date of Patent: May 1, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Masatake Tanaka, Yoshihiro Nakagawa, Naoya Isono, Harumi Takada, Reo Tagawa
  • Patent number: 9904193
    Abstract: Provided is a toner, including a toner particle containing: a binder resin containing a styrene acrylic resin as a main component, a colorant, a hydrocarbon wax, and a wax dispersant, in which: the wax dispersant includes a polymer of a vinyl resin component and a hydrocarbon compound, the vinyl resin component including styrene and one or more kinds of vinyl-based polymerizable monomers except a styrene derivative; and a solubility parameter of the binder resin (A) a solubility parameter of the vinyl resin segment of the wax dispersant (C), and a solubility parameter of the hydrocarbon compound segment of the wax dispersant (D) satisfy the formulae (1) and (2). |A?C|?0.20??(1) C?D<1.
    Type: Grant
    Filed: June 30, 2016
    Date of Patent: February 27, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yoshihiro Nakagawa, Masatake Tanaka, Naoya Isono, Harumi Takada
  • Patent number: 9835964
    Abstract: The present invention provides a toner that exhibits an excellent colorant dispersibility and hence maintains the formation of a high-quality image, that is capable of low-temperature fixing, and that has a satisfactory heat-resistant storability and a satisfactory durability, in which the toner comprising a toner particle that contains a colorant and a binder resin containing a styrene-acrylic resin and a crystalline resin, wherein a compatibility parameter (V) between the styrene-acrylic resin and the crystalline resin satisfies 0.40?V?1.10.
    Type: Grant
    Filed: November 26, 2014
    Date of Patent: December 5, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yu Yoshida, Masatake Tanaka, Yoshihiro Nakagawa, Naoya Isono, Tsutomu Shimano, Shintaro Noji
  • Patent number: 9829816
    Abstract: Provided is a toner for which the heat-resistant storability and the low-temperature fixability are able to co-exist at higher levels and for which the temporal stability of the low-temperature fixability is also excellent. The toner has a toner particle that contains a binder resin and a pigment, and this binder resin contains a polyester resin that has a specific structure and specific properties.
    Type: Grant
    Filed: June 11, 2015
    Date of Patent: November 28, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Masatake Tanaka, Yoshihiro Nakagawa, Naoya Isono, Tsutomu Shimano, Shintaro Noji, Yu Yoshida, Takeshi Kaburagi, Shohei Shibahara
  • Publication number: 20170299972
    Abstract: A toner having a toner particle containing a binder resin and a crystalline material, wherein when “a” is an endothermic quantity deriving from the crystalline material in a DSC of the toner and “b” is an endothermic quantity deriving from the crystalline material in a DSC of the toner that has been held for 10 hours in an environment with a temperature of 55° C. and a humidity of 8% RH, the “a” and “b” satisfy a relationship a/b?0.85; in a dynamic viscoelastic measurement of a non-melt-molded pellet of the toner, the toner has a temperature range A for which G??1×105 Pa and tan ?<1 are satisfied; and in a dynamic viscoelastic measurement of a melt-molded pellet of the toner, the toner has a temperature range B for which tan ?>1 is satisfied within the temperature range A.
    Type: Application
    Filed: April 13, 2017
    Publication date: October 19, 2017
    Inventors: Masatake Tanaka, Nobuhisa Abe, Hidekazu Fumita, Masashi Kawamura, Shiro Kuroki, Kenji Ookubo
  • Patent number: 9785071
    Abstract: The toner comprising a toner particle having a core-shell structure that contains a core containing an amorphous resin A and a crystalline resin and a shell containing an amorphous resin B, wherein the amorphous resin A contains a styrene-acrylic resin, the content of the styrene-acrylic resin is at least 50% by mass based on the total mass of the amorphous resin A, a degree of compatibility A between the amorphous resin A and the crystalline resin is at least 50% and not more than 100%, and a degree of compatibility B between the amorphous resin B and the crystalline resin is at least 0% and not more than 40%.
    Type: Grant
    Filed: August 11, 2016
    Date of Patent: October 10, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Tsutomu Shimano, Yoshihiro Nakagawa, Masatake Tanaka, Naoya Isono, Yu Yoshida
  • Patent number: 9766566
    Abstract: A toner includes a toner particle including a surface layer containing an organosilicon polymer. The toner particle contains a styrene acrylic resin and a block polymer that has i) a polyester segment C and a vinyl polymer segment A, the mass ratio C/A of the polyester segment C to the vinyl polymer segment A being 40/60 to 80/20, and ii) a melting point Tm of 55° C. to 90° C. The organosilicon polymer has a partial structure represented by Rf—SiO3/2.
    Type: Grant
    Filed: May 26, 2016
    Date of Patent: September 19, 2017
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shinsuke Mochizuki, Kenichi Nakayama, Koji Abe, Toshihiko Katakura, Masatake Tanaka, Naoya Isono
  • 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