Patents by Inventor Yuto Onozaki

Yuto Onozaki 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: 20220236657
    Abstract: A magnetic carrier including a magnetic core and a coating resin configured to coat the surface of the magnetic core. The coating resin contains a graft resin A and a graft resin B. The coating resin (i) contains 1.0 mass % or more and 50.0 mass % or less of the graft resin A, and (ii) contains 50.0 mass % or more and 99.0 mass % or less of the graft resin B. The graft resin A has a unit Y1 represented by formula (1) and a unit Y2 represented by formula (2). The graft resin B (i) is a comb-shaped polymer having, as a branch, at least one moiety selected from, for example, a styrene-based polymer moiety and a (meth)acrylate-based polymer moiety, and (ii) contains the polysiloxane structure moiety at a content of 0.1 mass % or less.
    Type: Application
    Filed: January 26, 2022
    Publication date: July 28, 2022
    Inventors: Yuto Onozaki, Ryuji Murayama, Nobuhiro Yoshida, Hironori Minagawa
  • Publication number: 20220236660
    Abstract: A magnetic carrier including: a magnetic core; and a coating resin that coats a surface of the magnetic core, wherein the resin coating layer has a thickness of 50 nm or more, a coating resin, which forms the resin coating layer, contains a resin S having an organosilicon polymer moiety, and when a surface and a position at a depth of 20 nm from the surface of the magnetic carrier are analyzed by X-ray photoelectron spectroscopy, an amount of silicon element as determined by the analysis has a ratio within a specific range at respective positions.
    Type: Application
    Filed: January 21, 2022
    Publication date: July 28, 2022
    Inventors: Ryuji Murayama, Hironori Minagawa, Yuto Onozaki, Nobuhiro Yoshida
  • Publication number: 20220236658
    Abstract: A magnetic carrier includes a magnetic core and a coating resin that covers a surface of the magnetic core. The coating resin includes a resin A and a resin B. A content of the resin A is 1 to 50% by mass, and a content of the resin B is 50 to 99% by mass, with respect to the coating resin. The resin A has a particular unit Y1 and a particular unit Y2, and the resin B contains 0.1% by mass or less of the particular unit Y2. When a mass of the resin A is represented by X, a mass of the unit Y1 is represented by Ma, and a mass of the unit Y2 is represented by Mb, 0.90?(Ma+Mb)/X?1.00 and 1.00?Ma/Mb?30.0 are satisfied, and also 0?|SPa?SPb|?2.0 is satisfied.
    Type: Application
    Filed: January 24, 2022
    Publication date: July 28, 2022
    Inventors: Ryuji Murayama, Yuto Onozaki, Nobuhiro Yoshida, Hironori Minagawa
  • Publication number: 20210389688
    Abstract: A negative-charging toner comprising a toner particle comprising a binder resin and an organic-inorganic composite fine particle comprising resin fine particles and inorganic fine particles A, wherein the organic-inorganic composite fine particle is negative charging, the organic-inorganic composite fine particle has a structure in which at least a part of the inorganic fine particle A is embedded in the resin fine particle, a number average particle diameter Db of the organic-inorganic composite fine particle is 50 to 350 nm, and a plurality of convex portions derived from the inorganic fine particles A are present on the surface of the organic-inorganic composite fine particle.
    Type: Application
    Filed: June 2, 2021
    Publication date: December 16, 2021
    Inventors: Takaho Shibata, Ryuji Murayama, Ryuichiro Matsuo, Yuto Onozaki, Kenta Mitsuiki, Megumi Shino, Hironori Minagawa
  • Patent number: 11131939
    Abstract: A toner including a toner particle that contains a binder resin, and an inorganic fine particle, wherein the inorganic fine particle contains aggregated particles; the aggregated particles contain primary particles of at least one metal salt selected from the group consisting of titanate metal salts and zirconate metal salts; the primary particles have a number-average particle diameter of from 15 nm to 55 nm; the aggregated particles have an aggregation diameter of from 80 nm to 300 nm, the aggregated particles have a volume resistivity of from 2×109 ?·cm to 2×1013 ?·cm; and the aggregated particles cover a surface of the toner particle, and a coverage ratio of the aggregated particles with respect to the surface of the toner particle is from 0.3 area % to 10.0 area %.
    Type: Grant
    Filed: August 26, 2019
    Date of Patent: September 28, 2021
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Masayuki Hama, Yuto Onozaki, Takeshi Hashimoto, Megumi Shino, Ichiro Kanno, Nozomu Komatsu, Hiroyuki Fujikawa
  • Patent number: 10955765
    Abstract: A magnetic carrier comprising a magnetic carrier particle having a magnetic carrier particle having a magnetic carrier core particle and a resin coat layer formed on the magnetic carrier core particle surface, and inorganic fine particles A present on a surface of the magnetic carrier particle, wherein each of the inorganic fine particles A has a rectangular parallelepiped particle shape, the inorganic fine particles A have D1 of 10 to 60 nm, the inorganic fine particles A are inorganic particles which have been surface treated with a surface treatment agent or silane coupling agent-treated particles, SP1 of the resin coat layer and SP2 of the surface treatment agent satisfies SP1?SP2?14.00, and the coverage ratio of the magnetic carrier surface by the inorganic fine particles A as measured by ESCA is 5.0 to 20.0 atom %: and a two-component developer comprising at least the magnetic carrier and a toner.
    Type: Grant
    Filed: November 18, 2019
    Date of Patent: March 23, 2021
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yuto Onozaki, Ichiro Kanno, Ryo Nakajima, Kazuyuki Sakamoto, Nozomu Komatsu, Takakuni Kobori, Hiroyuki Fujikawa
  • Patent number: 10935902
    Abstract: A toner including a toner particle that includes a binder resin and a crystalline polyester; and inorganic fine particles on the toner particle surface, wherein a content of the crystalline polyester is 0.5 to 20.0 mass parts per 100 mass parts of the binder resin; in the toner cross section, domains of the crystalline polyester are present in a dispersed state, the percentage for areas of these crystalline polyester domains in the region to a depth of 0.50 ?m from a contour of the toner particle is at least 10%, the number average of lengths of a major axis is 120 nm to 1000 nm, and the number average of aspect ratios is not more than 4; a dielectric constant of the inorganic fine particles is 25 to 300 pF/m; and a coverage ratio by the inorganic fine particles on the toner particle surface is 5% to 60%.
    Type: Grant
    Filed: December 3, 2019
    Date of Patent: March 2, 2021
    Assignee: Canon Kabushiki Kaisha
    Inventors: Ichiro Kanno, Nozomu Komatsu, Yuto Onozaki, Takakuni Kobori, Kazuyuki Sakamoto, Ryo Nakajima, Hiroyuki Fujikawa
  • Publication number: 20200183295
    Abstract: A toner including a toner particle that includes a binder resin and a crystalline polyester; and inorganic fine particles on the toner particle surface, wherein a content of the crystalline polyester is 0.5 to 20.0 mass parts per 100 mass parts of the binder resin; in the toner cross section, domains of the crystalline polyester are present in a dispersed state, the percentage for areas of these crystalline polyester domains in the region to a depth of 0.50 ?m from a contour of the toner particle is at least 10%, the number average of lengths of a major axis is 120 nm to 1000 nm, and the number average of aspect ratios is not more than 4; a dielectric constant of the inorganic fine particles is 25 to 300 pF/m; and a coverage ratio by the inorganic fine particles on the toner particle surface is 5% to 60%.
    Type: Application
    Filed: December 3, 2019
    Publication date: June 11, 2020
    Inventors: Ichiro Kanno, Nozomu Komatsu, Yuto Onozaki, Takakuni Kobori, Kazuyuki Sakamoto, Ryo Nakajima, Hiroyuki Fujikawa
  • Publication number: 20200166862
    Abstract: A magnetic carrier comprising a magnetic carrier particle having a magnetic carrier particle having a magnetic carrier core particle and a resin coat layer formed on the magnetic carrier core particle surface, and inorganic fine particles A present on a surface of the magnetic carrier particle, wherein each of the inorganic fine particles A has a rectangular parallelepiped particle shape, the inorganic fine particles A have D1 of 10 to 60 nm, the inorganic fine particles A are inorganic particles which have been surface treated with a surface treatment agent or silane coupling agent-treated particles, SP1 of the resin coat layer and SP2 of the surface treatment agent satisfies SP1?SP2?14.00, and the coverage ratio of the magnetic carrier surface by the inorganic fine particles A as measured by ESCA is 5.0 to 20.0 atom %: and a two-component developer comprising at least the magnetic carrier and a toner.
    Type: Application
    Filed: November 18, 2019
    Publication date: May 28, 2020
    Inventors: Yuto Onozaki, Ichiro Kanno, Ryo Nakajima, Kazuyuki Sakamoto, Nozomu Komatsu, Takakuni Kobori, Hiroyuki Fujikawa
  • Patent number: 10620556
    Abstract: A toner having chargeability and fluidity that do not change to a great extent is provided. The toner includes toner particles containing a binder resin and includes inorganic fine particles A, wherein the shape factor SF-2 of primary particles of the inorganic fine particles A is 116 or less, and regarding the particle size distribution on a volume basis of the inorganic fine particles A on the toner particle surfaces, the particle diameter when a cumulative value from the small particle side reaches 16% by volume is denoted as D16, the particle diameter when a cumulative value reaches 50% by volume is denoted as D50, and the particle diameter when a cumulative value reaches 84% by volume is denoted as D84, D50 is 80 nm or more and 200 nm or less, and the particle size distribution indicator A represented by D84/D16 is 1.70 or more and 2.60 or less.
    Type: Grant
    Filed: December 4, 2018
    Date of Patent: April 14, 2020
    Assignee: Canon Kabushiki Kaisha
    Inventors: Nozomu Komatsu, Masayuki Hama, Takeshi Hashimoto, Ichiro Kanno, Yuto Onozaki, Megumi Ikeda, Akifumi Matsubara, Hitoshi Sano, Takakuni Kobori, Hiroyuki Fujikawa
  • Patent number: 10599060
    Abstract: A toner including: a toner particle, wherein the toner particle contains a binder resin, a compound represented by formula (1) below, and a compound in which at least a compound represented by formula (2) below and a compound represented by formula (3) below are in solid solution. In formula (1), R1, R2, R3, and R6 each independently represent an alkyl group or aryl group, and R4 and R5 each independently represent an aryl group, acyl group, or alkyl group, or R4 is bonded to R5 to form a cyclic organic functional group that contains R4, R5, and the nitrogen atom to which R4 and R5 are bonded.
    Type: Grant
    Filed: November 30, 2018
    Date of Patent: March 24, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Ichiro Kanno, Takeshi Hashimoto, Nozomu Komatsu, Masayuki Hama, Yuto Onozaki, Megumi Ikeda, Hiroyuki Fujikawa
  • Publication number: 20200073263
    Abstract: A toner including a toner particle that contains a binder resin, and an inorganic fine particle, wherein the inorganic fine particle contains aggregated particles; the aggregated particles contain primary particles of at least one metal salt selected from the group consisting of titanate metal salts and zirconate metal salts; the primary particles have a number-average particle diameter of from 15 nm to 55 nm; the aggregated particles have an aggregation diameter of from 80 nm to 300 nm, the aggregated particles have a volume resistivity of from 2×109 ?·cm to 2×1013 ?·cm; and the aggregated particles cover a surface of the toner particle, and a coverage ratio of the aggregated particles with respect to the surface of the toner particle is from 0.3 area % to 10.0 area %.
    Type: Application
    Filed: August 26, 2019
    Publication date: March 5, 2020
    Inventors: Masayuki Hama, Yuto Onozaki, Takeshi Hashimoto, Megumi Shino, Ichiro Kanno, Nozomu Komatsu, Hiroyuki Fujikawa
  • Patent number: 10564560
    Abstract: Provided is a toner having a toner particle, wherein the toner particle contains a polyester resin and a fatty acid metal salt, the toner contains a tetrahydrofuran-soluble component A with a molecular weight of at least 1,000 and not more than 5,000, as measured by gel permeation chromatography, in an amount of at least 25 mass % and not more than 80 mass %, and a mass ratio of the fatty acid metal salt to the tetrahydrofuran-soluble component A is at least 0.003 and not more than 0.060.
    Type: Grant
    Filed: June 4, 2018
    Date of Patent: February 18, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yuto Onozaki, Takeshi Hashimoto, Ichiro Kanno, Masayuki Hama, Nozomu Komatsu, Hiroyuki Fujikawa
  • Patent number: 10474049
    Abstract: By controlling the migration to the toner particle surface of the crystalline polyester present in the toner particle, a toner is provided that exhibits an excellent durability in long-term use, a stable charging performance after holding in a high-temperature, high-humidity environment, and an excellent low-temperature fixability, in which the toner having a toner particle that contains an amorphous resin, a crystalline polyester, and a wax, wherein the toner particle includes, at the surface thereof, a coat layer containing a cyclic polyolefin resin.
    Type: Grant
    Filed: March 20, 2019
    Date of Patent: November 12, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yuto Onozaki, Masayuki Hama, Takeshi Hashimoto, Ichiro Kanno, Hitoshi Sano, Akifumi Matsubara, Nozomu Komatsu, Takakuni Kobori, Hiroyuki Fujikawa, Tsubasa Fujisaki
  • Patent number: 10451986
    Abstract: According to the present invention, in a toner including a toner particle containing a binder resin and a low molecular aromatic hydrocarbon, the binder resin contains a polyester resin, at least one kind of a unit derived from an aromatic monocarboxylic acid and a unit derived from an aromatic monoalcohol is contained, and the low molecular aromatic hydrocarbon has 1 or more and 4 or less benzene rings, and has a melting point of 60° C. or more and 120° C. or less.
    Type: Grant
    Filed: March 6, 2018
    Date of Patent: October 22, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Hitoshi Sano, Takeshi Hashimoto, Masayuki Hama, Ichiro Kanno, Yuto Onozaki, Akifumi Matsubara, Megumi Ikeda, Nozomu Komatsu, Takakuni Kobori, Hiroyuki Fujikawa
  • Patent number: 10423086
    Abstract: Provided is a toner containing: a toner particle containing a binder resin; and an inorganic particle, wherein the inorganic particle contains a silicon oxide particle with a number-average particle diameter (D1) from 50 nm to 300 nm and a strontium titanate particle with a number-average particle diameter (D1) from 10 nm to 60 nm, the content of the silicon oxide particle is from 0.5 to 15.0 mass parts per 100 mass parts of the toner particle, the content of the strontium titanate particle is from 0.02 to 5.00 times the content of the silicon oxide particle, and in dielectric constant measurement at 25° C. and 1 MHz, the dielectric constant of the silicon oxide particle is from 1.0 pF/m to 20.0 pF/m, and the dielectric constant of the strontium titanate is from 25.0 pF/m to 100.0 pF/m.
    Type: Grant
    Filed: May 30, 2018
    Date of Patent: September 24, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Masayuki Hama, Takeshi Hashimoto, Yuto Onozaki, Ichiro Kanno, Nozomu Komatsu, Hiroyuki Fujikawa
  • Patent number: 10401748
    Abstract: A toner comprises a toner particle containing an amorphous polyester, wherein the amorphous polyester contains an amorphous polyester 1, the amorphous polyester contains a tin compound and a titanium compound, a Sn/Ti abundance ratio between Sn and Ti in the amorphous polyester according to x-ray fluorescence analysis is 20/80 to 80/20, and a weight-average molecular weight Mw1 of the amorphous polyester 1 according to measurement by gel permeation chromatography (GPC) is Mw1<7,000.
    Type: Grant
    Filed: May 22, 2017
    Date of Patent: September 3, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Takeshi Hashimoto, Nozomu Komatsu, Yuto Onozaki, Akifumi Matsubara, Ichiro Kanno, Hitoshi Sano, Tsubasa Fujisaki, Masayuki Hama, Takakuni Kobori, Hiroyuki Fujikawa
  • Publication number: 20190219939
    Abstract: By controlling the migration to the toner particle surface of the crystalline polyester present in the toner particle, a toner is provided that exhibits an excellent durability in long-term use, a stable charging performance after holding in a high-temperature, high-humidity environment, and an excellent low-temperature fixability, in which the toner having a toner particle that contains an amorphous resin, a crystalline polyester, and a wax, wherein the toner particle includes, at the surface thereof, a coat layer containing a cyclic polyolefin resin.
    Type: Application
    Filed: March 20, 2019
    Publication date: July 18, 2019
    Inventors: Yuto Onozaki, Masayuki Hama, Takeshi Hashimoto, Ichiro Kanno, Hitoshi Sano, Akifumi Matsubara, Nozomu Komatsu, Takakuni Kobori, Hiroyuki Fujikawa, Tsubasa Fujisaki
  • Publication number: 20190171125
    Abstract: A toner including: a toner particle, wherein the toner particle contains a binder resin, a compound represented by formula (1) below, and a compound in which at least a compound represented by formula (2) below and a compound represented by formula (3) below are in solid solution. In formula (1), R1, R2, R3, and R6 each independently represent an alkyl group or aryl group, and R4 and R5 each independently represent an aryl group, acyl group, or alkyl group, or R4 is bonded to R5 to form a cyclic organic functional group that contains R4, R5, and the nitrogen atom to which R4 and R5 are bonded.
    Type: Application
    Filed: November 30, 2018
    Publication date: June 6, 2019
    Inventors: Ichiro Kanno, Takeshi Hashimoto, Nozomu Komatsu, Masayuki Hama, Yuto Onozaki, Megumi Ikeda, Hiroyuki Fujikawa
  • Patent number: 10274851
    Abstract: A toner is provided, which contains a toner particle and a metal titanate particle, wherein, in a number-based particle size distribution of the metal titanate particle on the surface of the toner particle, when D10, D50 and D90 denote the particle diameter at which the cumulative value from the small particle diameter side reaches 10% by number, 50% by number and 90% by number, respectively, the D50 is at least 10 nm and not more than 90 nm, and the particle size distribution index A, which is represented by D90/D10, is at least 2.00 and not more than 10.00, and the value of storage elastic modulus G? at 40° C. in viscoelasticity measurements of the toner is at least 1.0×107 Pa and not more than 1.0×1010 Pa.
    Type: Grant
    Filed: February 2, 2018
    Date of Patent: April 30, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Takeshi Hashimoto, Masayuki Hama, Yuto Onozaki, Ichiro Kanno, Nozomu Komatsu, Hiroyuki Fujikawa