Patents by Inventor Hirofumi Kyuushima

Hirofumi Kyuushima 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: 11774871
    Abstract: A toner comprising a toner particle, wherein the toner particle comprises a binder resin, the binder resin comprises a resin A and a resin B, the toner particle comprises protrusions on a surface thereof, each of the protrusions comprises the resin B, a shape factor SF-2 of the toner as observed under SEM is 105 to 120, and when the toner is observed under the SEM, a surface unevenness index of the toner as calculated by formula (1) below is 0.010 to 0.050: Surface unevenness index=(area of region surrounded by convex hull of toner?projected area of toner)/projected area of toner??(1).
    Type: Grant
    Filed: March 30, 2021
    Date of Patent: October 3, 2023
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yoshiaki Shiotari, Hirofumi Kyuushima, Shintaro Noji, Kazutaka Sasaki
  • Publication number: 20220404730
    Abstract: A toner comprising a toner particle comprising a binder resin, and an external additive, wherein the toner particle further comprises a monohydric aliphatic alcohol, the monohydric aliphatic alcohol has 8 to 18 carbon atoms, a content ratio of the monohydric aliphatic alcohol extracted from the toner with ethanol is 30 to 300 ppm by mass in the toner, and the external additive comprises at least one selected from the group consisting of hydrotalcite particles and alumina particles.
    Type: Application
    Filed: June 1, 2022
    Publication date: December 22, 2022
    Inventors: Tomoya Nagaoka, Takayuki Toyoda, Naoya Isono, Hirofumi Kyuushima, Masao Suzuki
  • Publication number: 20220397836
    Abstract: A toner comprising a toner particle comprising a binder resin, wherein the toner particle further comprises: a compound represented by R1—[OCH2CH2]n—OH, where, R1 represents a linear or branched alkyl group having 8 to 22 carbon atoms, and n is an integer of 1 to 3; and at least one polyvalent element selected from the group consisting of magnesium, calcium, aluminum, boron and iron, and a content of the polyvalent element in the toner is 100 mass ppm to 5000 mass ppm.
    Type: Application
    Filed: June 1, 2022
    Publication date: December 15, 2022
    Inventors: Takayuki Toyoda, Naoya Isono, Hirofumi Kyuushima, Masao Suzuki, Tomoya Nagaoka
  • Publication number: 20220390871
    Abstract: A toner comprising a toner particle comprising a binder resin, wherein the toner particle further comprises a monohydric aliphatic alcohol, and an anionic surfactant having an alkyl group, the binder resin comprises a polyester resin, a carbon number of the monohydric aliphatic alcohol is 8 to 18, a content of the monohydric aliphatic alcohol when extracted from the toner with ethanol is 30 to 300 ppm by mass in the toner, and a value of a ratio (molar ratio) of the monohydric aliphatic alcohol extracted from the toner with ethanol relative to the anionic surfactant having an alkyl group extracted from the toner with methanol is 0.01 to 0.60.
    Type: Application
    Filed: June 1, 2022
    Publication date: December 8, 2022
    Inventors: Naoya Isono, Takayuki Toyoda, Hirofumi Kyuushima, Tomoya Nagaoka, Masao Suzuki
  • Publication number: 20220390870
    Abstract: A toner comprising a toner particle comprising a binder resin, wherein the toner particle further comprises a compound represented by a following formula (1) and a pigment having a quinacridone structure; where, in the formula (1), R represents a linear or branched alkyl group having 4 to 22 carbon atoms, and n is an integer of 1 to 4.
    Type: Application
    Filed: June 1, 2022
    Publication date: December 8, 2022
    Inventors: Hirofumi Kyuushima, Takayuki Toyoda, Naoya Isono, Tomoya Nagaoka, Masao Suzuki
  • Patent number: 11397386
    Abstract: A toner comprising a toner particle that includes a binder resin, wherein in dynamic viscoelasticity measurement of the toner, the storage elastic modulus of the toner at 70° C. is from 0.10 MPa to 3.00 MPa, and in nanoindentation measurement of the toner, the surface storage elastic modulus of the toner at 25° C. under 150 ?N of load is from 2.80 GPa to 4.50 GPa.
    Type: Grant
    Filed: May 11, 2020
    Date of Patent: July 26, 2022
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Hirofumi Kyuushima, Yoshiaki Shiotari, Shintaro Noji, Mai Kato
  • Publication number: 20220146954
    Abstract: A toner comprises a toner particle comprising a core particle comprising a resin component, a shell coating the surface of the core particle, and a polyvalent metal. The resin component comprises a polyester resin, and the shell comprises an amino resin; in an electron image of a cross section of the toner acquired using a transmission electron microscope, a polyvalent metal content P(M) obtained by energy-dispersive x-ray analysis at the core/shell interface and in the vicinity of this interface is 0.0010 to 2.00 atomic %; and the surface storage elastic modulus of the toner at a load of 30 ?N at 25° C., according to nanoindentation measurement of the toner, is from 6.50 GPa to 12.00 GPa.
    Type: Application
    Filed: November 1, 2021
    Publication date: May 12, 2022
    Inventors: Mai Kato, Hirofumi Kyuushima, Naoya Isono, Kenichi Nakayama, Yoshiaki Shiotari
  • Publication number: 20220146953
    Abstract: A toner comprising a toner particle comprising a core particle comprising a binder resin, and a shell on a surface of the core particle, wherein the shell comprises an oxazoline group and a polyvalent metal, and in an electron image of a cross-section of the toner particle taken with a transmission electron microscope, the polyvalent metal has atomic concentration C(M) of 0.0010 to 0.5000 atomic % as measured by energy dispersive X-ray analysis of the shell.
    Type: Application
    Filed: November 1, 2021
    Publication date: May 12, 2022
    Inventors: Hirofumi Kyuushima, Mai Kato, Naoya Isono, Shintaro Noji, Kenichi Nakayama
  • Publication number: 20220075284
    Abstract: A toner comprising a toner particle and a silica particle on a surface of the toner particle, wherein an area formed by a polyester resin and an area formed by a styrene-acrylic resin are present on the surface of the toner particle; the silica particle has the number-average particle diameter of 15 to 60 nm; the silica particle has the average pore diameter of 5.0 to 20.0 nm; and the silica particle has the total pore volume of 0.20 to 1.50 cm3/g.
    Type: Application
    Filed: September 3, 2021
    Publication date: March 10, 2022
    Inventors: Kenichi Nakayama, Naoya lsono, Yoshiaki Shiotari, Hirofumi Kyuushima
  • Publication number: 20210318631
    Abstract: The toner includes a toner particle that comprising a core particle containing a resin component and a shell on a surface of the core particle, wherein the resin component comprises more than 50.0 mass % of a polyester resin comprising a monomer unit that contains a heterocyclic group, and the shell comprises at least one resin selected from the group consisting of prescribed (meth)acrylic resins and melamine resins.
    Type: Application
    Filed: March 18, 2021
    Publication date: October 14, 2021
    Inventors: Naoya Isono, Kenichi Nakayama, Hirofumi Kyuushima, Mai Kato
  • Publication number: 20210311405
    Abstract: A toner comprising a toner particle, wherein the toner particle comprises a binder resin, the binder resin comprises a resin A and a resin B, the toner particle comprises protrusions on a surface thereof, each of the protrusions comprises the resin B, a shape factor SF-2 of the toner as observed under SEM is 105 to 120, and when the toner is observed under the SEM, a surface unevenness index of the toner as calculated by formula (1) below is 0.010 to 0.050: Surface unevenness index=(area of region surrounded by convex hull of toner?projected area of toner)/projected area of toner??(1).
    Type: Application
    Filed: March 30, 2021
    Publication date: October 7, 2021
    Inventors: Yoshiaki Shiotari, Hirofumi Kyuushima, Shintaro Noji, Kazutaka Sasaki
  • Publication number: 20200363742
    Abstract: A toner comprising a toner particle that includes a binder resin, wherein in dynamic viscoelasticity measurement of the toner, the storage elastic modulus of the toner at 70° C. is from 0.10 MPa to 3.00 MPa, and in nanoindentation measurement of the toner, the surface storage elastic modulus of the toner at 25° C. under 150 ?N of load is from 2.80 GPa to 4.50 GPa.
    Type: Application
    Filed: May 11, 2020
    Publication date: November 19, 2020
    Inventors: Hirofumi Kyuushima, Yoshiaki Shiotari, Shintaro Noji, Mai Kato
  • Patent number: 10747136
    Abstract: A toner comprising a toner particle having a binder resin and a colorant, and metal titanate fine particles, wherein the toner particle includes a polyvalent metal element having an electric resistivity of from 2.5×10?8 ?·m to 10.0×10?8 ?·m; the amount of the polyvalent metal element in the toner particle is from 0.080 ?mol/g to 20.000 ?mol/g; the metal titanate fine particles have a perovskite crystal structure; and the number average particle diameter of primary particles of the metal titanate fine particles is from 10 nm to 80 nm.
    Type: Grant
    Filed: April 23, 2019
    Date of Patent: August 18, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Takashi Kenmoku, Shota Amano, Tomohiro Unno, Hirofumi Kyuushima
  • Publication number: 20190332027
    Abstract: A toner comprising a toner particle having a binder resin and a colorant, and metal titanate fine particles, wherein the toner particle includes a polyvalent metal element having an electric resistivity of from 2.5×10?8 ?·m to 10.0×10?8 ?·m; the amount of the polyvalent metal element in the toner particle is from 0.080 ?mol/g to 20.000 ?mol/g; the metal titanate fine particles have a perovskite crystal structure; and the number average particle diameter of primary particles of the metal titanate fine particles is from 10 nm to 80 nm.
    Type: Application
    Filed: April 23, 2019
    Publication date: October 31, 2019
    Inventors: Takashi Kenmoku, Shota Amano, Tomohiro Unno, Hirofumi Kyuushima
  • Patent number: 9785068
    Abstract: The toner has a toner particle that contains a binder resin and a wax, wherein the wax is present in domain form in the interior of the toner particle; the proportion of toner particles for which the position of the wax domains are controlled, is in a prescribed range; using d for a major axis length of the domain having the largest major axis length and using D for a number-average particle diameter of the toner, the d and D satisfy a prescribed relationship; and the ratio between the major axis length and the minor axis length of the domain having the largest major axis length is in a prescribed range.
    Type: Grant
    Filed: August 24, 2016
    Date of Patent: October 10, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Noriyoshi Umeda, Takeshi Kaburagi, Naotaka Ikeda, Hirofumi Kyuushima, Shohei Shibahara, Yoshiaki Wada
  • Publication number: 20170075243
    Abstract: The toner has a toner particle that contains a binder resin and a wax, wherein the wax is present in domain form in the interior of the toner particle; the proportion of toner particles for which the position of the wax domains are controlled, is in a prescribed range; using d for a major axis length of the domain having the largest major axis length and using D for a number-average particle diameter of the toner, the d and D satisfy a prescribed relationship; and the ratio between the major axis length and the minor axis length of the domain having the largest major axis length is in a prescribed range.
    Type: Application
    Filed: August 24, 2016
    Publication date: March 16, 2017
    Inventors: Noriyoshi Umeda, Takeshi Kaburagi, Naotaka Ikeda, Hirofumi Kyuushima, Shohei Shibahara, Yoshiaki Wada