Patents by Inventor Masayuki Hama

Masayuki Hama 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: 20240004324
    Abstract: A yellow toner including a toner particle including a binder resin, a crystalline resin, and C.I. Pigment Yellow 180, a content of the C.I. Pigment Yellow 180 is 3% by mass or more and 15% by mass or less with respect to a mass of the toner, the C.I. Pigment Yellow 180 is in a form of plate-like particles each having a plate-like shape, and when the C.I. Pigment Yellow 180 is observed with a scanning electron microscope, the plate-like particles of the C.I. Pigment Yellow 180 satisfy the following relationships: S/Z?10.0; and 50?S?300, where the S (nm) represents a number average of circle-equivalent diameters calculated from areas of surfaces having largest areas of the plate-like particles, and the Z (nm) represents a number average of widths in directions perpendicular to the surfaces having the largest areas of the plate-like particles.
    Type: Application
    Filed: June 14, 2023
    Publication date: January 4, 2024
    Inventors: KOUICHIROU OCHI, MASAYUKI HAMA, HAYATO IDA
  • Patent number: 11662670
    Abstract: A toner having: a toner particle containing a binder resin including a first resin that is a crystalline resin and a second resin that is an amorphous resin; and a fine particle on a surface of the toner particle, wherein the first resin contains a specific ratio of a specific monomer unit, an acid value of the first resin and an acid value of the second resin arc within specific ranges, a domain-matrix structure formed of a matrix containing the first resin and domains containing the second resin appears in cross -sectional observation of the toner, and the fine particle has on the surface a compound containing nitrogen atoms bound or adsorbed thereon.
    Type: Grant
    Filed: December 11, 2020
    Date of Patent: May 30, 2023
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Masayuki Hama, Ichiro Kanno, Kentaro Kamae, Takeshi Hashimoto, Hayato Ida
  • Publication number: 20230152725
    Abstract: A toner comprising a toner particle comprising an organic pigment and a binder resin, wherein, in a solid-state NMR measurement at 60° C. using a solid fraction obtained by specific procedure for dissolving the toner in chloroform as a sample, a transverse relaxation time T2 of a peak observed between 1.5 and 2.5 ppm is from 0.08 to 0.13 ms.
    Type: Application
    Filed: November 8, 2022
    Publication date: May 18, 2023
    Inventors: Kouichirou Ochi, Masayuki Hama, Yuka Gunji, Hayato Ida, Kaoru Yoshida
  • Publication number: 20220342335
    Abstract: A toner comprising a toner particle comprising a colorant, a binder resin, and calcium carbonate particles, wherein an amount of the colorant in the toner particle is from 1.0 to 20.0% by mass; the binder resin comprises a polyester resin; the polyester resin has an aromatic ring concentration of from 50 to 70 mol %; a surface of the calcium carbonate particles is coated with a fatty acid; an amount of the calcium carbonate particles in the toner particle is from 1.0 to 15.0% by mass; a number average particle diameter of the calcium carbonate particles is from 150 nm to 800 nm.
    Type: Application
    Filed: April 13, 2022
    Publication date: October 27, 2022
    Inventors: Kouichirou Ochi, Masayuki Hama, Hayato Ida, Yuya Chimoto, Hisasuke Kajihara
  • Publication number: 20220197174
    Abstract: A toner having high rub resistance is provided. A toner including a toner particle containing a binder resin and a calcium carbonate particle, wherein in X-ray diffractometry of the toner particle by CuK? radiation, when the Bragg angle is defined as ?, (i) the calcium carbonate particle has peaks at 2? of 26.5°±0.5° and 29.5°±0.5°, (ii) a crystallite diameter of crystals thereof attributed to 2?=29.5°±0.5° is 10 nm or more and 45 nm or less, and (iii) the ratio (a/b) of a peak intensity “a” at 2?=26.5°±0.5° to a peak intensity “b” at 20?=29.5°±0.5° is 0.15 or more and 0.24 or less.
    Type: Application
    Filed: November 29, 2021
    Publication date: June 23, 2022
    Inventors: Hisasuke Kajihara, Yuya Chimoto, Hayato Ida, Kouichirou Ochi, Kazuhisa Shirayama, Masayuki Hama
  • Publication number: 20220197166
    Abstract: A toner including a toner particle which contains: a resin component containing a binder resin; and an inorganic fine particle, the inorganic fine particle is at least one inorganic fine particle selected from the group consisting of (i) a particle containing CaCO3, (ii) a particle containing BaSO4, (iii) a particle containing Mg3Si4O10(OH)2, and (iv) a particle containing Al2Si2O5(OH)4, a number average particle diameter Dc of a primary particle of the inorganic fine particle is 100 nm or more and 1000 nm or less, when a cross section of the toner particle is observed, an inorganic fine particle domain A having a dispersion diameter of 2.0 times or more of Dc is present in the cross section, and the inorganic fine particle and the inorganic fine particle domain A occupy a specific percentage of an area in the cross section of the toner particle.
    Type: Application
    Filed: December 6, 2021
    Publication date: June 23, 2022
    Inventors: Yuya Chimoto, Masayuki Hama, Hayato Ida, Kouichirou Ochi, Kazuhisa Shirayama, Hisasuke Kajihara
  • 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
  • Publication number: 20210181650
    Abstract: A toner having: a toner particle containing a binder resin including a first resin that is a crystalline resin and a second resin that is an amorphous resin; and a fine particle on a surface of the toner particle, wherein the first resin contains a specific ratio of a specific monomer unit, an acid value of the first resin and an acid value of the second resin are within specific ranges, a domain-matrix structure formed of a matrix containing the first resin and domains containing the second resin appears in cross-sectional observation of the toner, and the fine particle has on the surface a compound containing nitrogen atoms bound or adsorbed thereon.
    Type: Application
    Filed: December 11, 2020
    Publication date: June 17, 2021
    Inventors: Masayuki Hama, lchiro Kanno, Kentaro Kamae, Takeshi Hashimoto, Hayato Ida
  • 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
  • Publication number: 20190107791
    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: Application
    Filed: December 4, 2018
    Publication date: April 11, 2019
    Inventors: Nozomu Komatsu, Masayuki Hama, Takeshi Hashimoto, Ichiro Kanno, Yuto Onozaki, Megumi Ikeda, Akifumi Matsubara, Hitoshi Sano, Takakuni Kobori, Hiroyuki Fujikawa