Patents by Inventor Wakiko Katsumata

Wakiko Katsumata 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: 11720036
    Abstract: A toner comprising a toner particle comprising a binder resin including a polyester resin, and a polyolefin resin having a sulfonic acid group, wherein the polyolefin resin having a sulfonic acid group is a polymer in which a vinyl polymer is bonded to a polyolefin, a content ratio of a monomer unit containing a sulfonic acid group in the vinyl polymer is from 1.0 mass % to 20.0 mass %, in a FT-IR spectrum obtained through measurement of a large particle size toner and a small particle size toner resulting from dividing, on a number basis, the toner into two substantially equal parts, a ratio of an intensity of a maximum absorption peak in a range from 1130 cm?1 to 1170 cm?1 with respect to an intensity of a maximum absorption peak in a range from 1713 cm?1 to 1723 cm?1 exhibits a specific relationship.
    Type: Grant
    Filed: June 10, 2021
    Date of Patent: August 8, 2023
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Takakuni Kobori, Kenta Mitsuiki, Hitoshi Sano, Wakiko Katsumata, Daisuke Yamashita, Yosuke Iwasaki, Takeshi Ohtsu, Takaho Shibata, Masaharu Miura, Koh Ishigami, Yuichi Mizo
  • Patent number: 11429032
    Abstract: A toner containing a toner particle that contains a binder resin including a polyester resin, and a polyolefin resin having —COOM that is a neutralized carboxy group with a monovalent metal ion M, wherein the polyolefin resin having —COOM is a polymer in which a vinyl polymer is bonded to a polyolefin, a content of a monomer unit containing —COOM in the polyolefin resin having —COOM is 1 to 20 mass %, and in a FT-IR spectrum obtained through measurement of a large particle size-side particle group and a small particle size-side particle group obtained by dividing the toner into two substantially equal parts, on a number basis, a ratio of the intensity of a maximum absorption peak in a range from 1545 cm?1 to 1555 cm?1 with respect to the intensity of a maximum absorption peak in a range from 1713 cm?1 to 1723 cm?1 exhibits a specific relationship.
    Type: Grant
    Filed: August 26, 2020
    Date of Patent: August 30, 2022
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Takaho Shibata, Yuichi Mizo, Koh Ishigami, Takakuni Kobori, Masaharu Miura, Takeshi Ohtsu, Yosuke Iwasaki, Daisuke Yamashita, Ryo Nakajima, Wakiko Katsumata, Hitoshi Sano, Kenta Mitsuiki, Rei Hijikawa
  • Publication number: 20210397106
    Abstract: A toner comprising a toner particle comprising a binder resin including a polyester resin, and a polyolefin resin having a sulfonic acid group, wherein the polyolefin resin having a sulfonic acid group is a polymer in which a vinyl polymer is bonded to a polyolefin, a content ratio of a monomer unit containing a sulfonic acid group in the vinyl polymer is from 1.0 mass % to 20.0 mass %, in a FT-IR spectrum obtained through measurement of a large particle size toner and a small particle size toner resulting from dividing, on a number basis, the toner into two substantially equal parts, a ratio of an intensity of a maximum absorption peak in a range from 1130 cm?1 to 1170 cm?1 with respect to an intensity of a maximum absorption peak in a range from 1713 cm?1 to 1723 cm?1 exhibits a specific relationship.
    Type: Application
    Filed: June 10, 2021
    Publication date: December 23, 2021
    Inventors: Takakuni Kobori, Kenta Mitsuiki, Hitoshi Sano, Wakiko Katsumata, Daisuke Yamashita, Yosuke Iwasaki, Takeshi Ohtsu, Takaho Shibata, Masaharu Miura, Koh Ishigami, Yuichi Mizo
  • Publication number: 20210286282
    Abstract: The present invention provides a white toner which has high charge uniformity and enables stable print-out of high-quality images irrespective of its usage environment. The above object can be solved by a white toner including a white toner particle containing a binder resin, a white pigment and an inorganic fine particle, in which the white pigment has a work function of 5.80 eV or more and 6.10 eV or less, the content of the white pigment is 15.0 parts by mass or more and 60.0 parts by mass or less relative to 100 parts by mass of the binder resin, and the inorganic fine particle has a work function of 6.15 eV or more.
    Type: Application
    Filed: May 28, 2021
    Publication date: September 16, 2021
    Inventors: Takakuni Kobori, Kenta Mitsuiki, Hitoshi Sano, Wakiko Katsumata, Daisuke Yamashita, Yosuke Iwasaki, Takeshi Ohtsu, Takaho Shibata, Masaharu Miura, Koh lshigami, Yuichi Mizo
  • Publication number: 20210063903
    Abstract: A toner containing a toner particle that contains a binder resin including a polyester resin, and a polyolefin resin having —COOM that is a neutralized carboxy group with a monovalent metal ion M, wherein the polyolefin resin having —COOM is a polymer in which a vinyl polymer is bonded to a polyolefin, a content of a monomer unit containing —COOM in the polyolefin resin having —COOM is 1 to 20 mass %, and in a FT-IR spectrum obtained through measurement of a large particle size-side particle group and a small particle size-side particle group obtained by dividing the toner into two substantially equal parts, on a number basis, a ratio of the intensity of a maximum absorption peak in a range from 1545 cm?1 to 1555 cm?1 with respect to the intensity of a maximum absorption peak in a range from 1713 cm?1 to 1723 cm?1 exhibits a specific relationship.
    Type: Application
    Filed: August 26, 2020
    Publication date: March 4, 2021
    Inventors: Takaho Shibata, Yuichi Mizo, Koh Ishigami, Takakuni Kobori, Masaharu Miura, Takeshi Ohtsu, Yosuke Iwasaki, Daisuke Yamashita, Ryo Nakajima, Wakiko Katsumata, Hitoshi Sano, Kenta Mitsuiki, Rei Hijikawa
  • Patent number: 10877386
    Abstract: A toner comprises a toner particle and an external additive, the toner satisfies a certain relationship with regard to ?l (C/m2) and ?s (C/m2). The toner is divided into two groups i.e. a first group and a second group with inertial classifier, the first group including a larger size of the toner particles, and the second group including a smaller size of the toner particles, and the number of the toner particles in the first group being substantially equal to the number of the toner particles in the second group. Then, al (C/m2) represents an absolute value of average surface charge density of the toner included in the first group, and ?s (C/m2) represents an absolute value of average surface charge density of the toner included in the second group.
    Type: Grant
    Filed: August 6, 2019
    Date of Patent: December 29, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Ryuji Murayama, Junichi Tamura, Kentaro Kamae, Hayato Ida, Daisuke Yamashita, Masaharu Miura, Takaho Shibata, Wakiko Katsumata, Yuichi Mizo
  • Patent number: 10852652
    Abstract: A toner containing a toner particle, in which the toner particle contains a binder resin and a pigment, and As and Al satisfy a specific relation, in a case when the toner is divided into two groups i.e. a first group and a second group with an inertial classifier, the first group including a larger size of the toner particles, and the second group including a smaller size of the toner particles, and the number of the toner particles in the first group being substantially equal to the number of the toner particles in the second group. Each of As and Al is a change rate of a surface potential of a pellet type molded product obtained by molding each of the toner in the first group and the toner in the second group under specific conditions is observed using a surface potentiometer under a specific conditions.
    Type: Grant
    Filed: August 9, 2019
    Date of Patent: December 1, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Daisuke Yamashita, Masaharu Miura, Takaho Shibata, Wakiko Katsumata, Yuichi Mizo
  • Patent number: 10809640
    Abstract: A toner that is suppressed from deteriorating owing to its long-term use and can maintain high transferability. The toner includes: a toner particle containing an amorphous polyester serving as a binder resin and a polymer A; and inorganic fine particles, wherein the polymer A includes a graft copolymer of a polyolefin and a vinyl-based polymer unit having a carboxylate anion group, and a metal ion having a valence of 2 or more.
    Type: Grant
    Filed: August 26, 2019
    Date of Patent: October 20, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yosuke Iwasaki, Kenta Mitsuiki, Wakiko Katsumata, Takeshi Ohtsu, Masaharu Miura, Koh Ishigami, Takakuni Kobori, Takaho Shibata, Daisuke Yamashita, Hitoshi Sano, Ryo Nakajima, Rei Hijikawa, Yuichi Mizo
  • Patent number: 10642178
    Abstract: A toner comprising a toner particle including a binder resin and a crystalline polyester resin, wherein the binder resin is an amorphous polyester resin having a linear alkyl group at a molecular chain terminal; the crystalline polyester resin is a polycondensate of a diol and a dicarboxylic acid; the number of carbon atoms CaPES of the linear alkyl group, the number of carbon atoms COH of the diol, and the number of carbon atoms CAc of the dicarboxylic acid, excluding carbon that belongs to carboxyl groups, satisfy the following relationships; and a glass transition temperature of the toner as measured by a differential scanning calorimeter is from 40.0° C. to 55.0° C. 8?CaPES?20??(1) CAc/COH?3.5 and 0?|CAc?CaPES|?3??(2) COH/CAc?3.
    Type: Grant
    Filed: April 8, 2019
    Date of Patent: May 5, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Daisuke Yamashita, Yuichi Mizo, Koh Ishigami, Masaharu Miura, Takaho Shibata, Takeshi Ohtsu, Yosuke Iwasaki, Wakiko Katsumata, Hitoshi Sano, Kenta Mitsuiki, Takakuni Kobori, Rei Hijikawa
  • Publication number: 20200073264
    Abstract: A toner that is suppressed from deteriorating owing to its long-term use and can maintain high transferability. The toner includes: a toner particle containing an amorphous polyester serving as a binder resin and a polymer A; and inorganic fine particles, wherein the polymer A includes a graft copolymer of a polyolefin and a vinyl-based polymer unit having a carboxylate anion group, and a metal ion having a valence of 2 or more.
    Type: Application
    Filed: August 26, 2019
    Publication date: March 5, 2020
    Inventors: Yosuke Iwasaki, Kenta Mitsuiki, Wakiko Katsumata, Takeshi Ohtsu, Masaharu Miura, Koh Ishigami, Takakuni Kobori, Takaho Shibata, Daisuke Yamashita, Hitoshi Sano, Ryo Nakajima, Rei Hijikawa, Yuichi Mizo
  • Publication number: 20200057398
    Abstract: A toner containing a toner particle, in which the toner particle contains a binder resin and a pigment, and As and Al satisfy a specific relation, in a case when the toner is divided into two groups i.e. a first group and a second group with an inertial classifier, the first group including a larger size of the toner particles, and the second group including a smaller size of the toner particles, and the number of the toner particles in the first group being substantially equal to the number of the toner particles in the second group. Each of As and Al is a change rate of a surface potential of a pellet type molded product obtained by molding each of the toner in the first group and the toner in the second group under specific conditions is observed using a surface potentiometer under a specific conditions.
    Type: Application
    Filed: August 9, 2019
    Publication date: February 20, 2020
    Inventors: Daisuke Yamashita, Masaharu Miura, Takaho Shibata, Wakiko Katsumata, Yuichi Mizo
  • Publication number: 20200057397
    Abstract: A toner comprises a toner particle and an external additive, the toner satisfies a certain relationship with regard to ?l (C/m2) and ?s (C/m2). The toner is divided into two groups i.e. a first group and a second group with inertial classifier, the first group including a larger size of the toner particles, and the second group including a smaller size of the toner particles, and the number of the toner particles in the first group being substantially equal to the number of the toner particles in the second group. Then, al (C/m2) represents an absolute value of average surface charge density of the toner included in the first group, and ?s (C/m2) represents an absolute value of average surface charge density of the toner included in the second group.
    Type: Application
    Filed: August 6, 2019
    Publication date: February 20, 2020
    Inventors: Ryuji Murayama, Junichi Tamura, Kentaro Kamae, Hayato Ida, Daisuke Yamashita, Masaharu Miura, Takaho Shibata, Wakiko Katsumata, Yuichi Mizo
  • Publication number: 20190339629
    Abstract: A toner comprising a toner particle including a binder resin and a crystalline polyester resin, wherein the binder resin is an amorphous polyester resin having a linear alkyl group at a molecular chain terminal; the crystalline polyester resin is a polycondensate of a diol and a dicarboxylic acid; the number of carbon atoms CaPES of the linear alkyl group, the number of carbon atoms COH of the diol, and the number of carbon atoms CAc of the dicarboxylic acid, excluding carbon that belongs to carboxyl groups, satisfy the following relationships; and a glass transition temperature of the toner as measured by a differential scanning calorimeter is from 40.0° C. to 55.0° C. 8?CaPES?20??(1) CAc/COH?3.5 and 0?|CAc?CaPES|?3??(2) COH/CAc?3.
    Type: Application
    Filed: April 8, 2019
    Publication date: November 7, 2019
    Inventors: Daisuke Yamashita, Yuichi Mizo, Koh Ishigami, Masaharu Miura, Takaho Shibata, Takeshi Ohtsu, Yosuke Iwasaki, Wakiko Katsumata, Hitoshi Sano, Kenta Mitsuiki, Takakuni Kobori, Rei Hijikawa
  • Patent number: 10423090
    Abstract: Provided is a magenta toner having a magenta toner particle containing a binder resin, a colorant, a wax, a wax dispersant, and a crystalline polyester, wherein the wax dispersant is a graft polymer in which a styrene acrylic resin is grafted to a hydrocarbon compound, and the styrene acrylic resin has a monomer unit having a saturated alicyclic group, the colorant contains C.I. Pigment Red 32, and when observing a cross-section of the magenta toner particle using a transmission electron microscope (TEM), crystals of the crystalline polyester are dispersed in the cross-section, and the number average value of maximum lengths of the crystals is 50 nm or less.
    Type: Grant
    Filed: November 29, 2018
    Date of Patent: September 24, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Takeshi Ohtsu, Yosuke Iwasaki, Wakiko Katsumata, Koh Ishigami, Masaharu Miura, Kentaro Kamae, Kenta Mitsuiki, Ryuichiro Matsuo, Yuichi Mizo
  • Publication number: 20190171123
    Abstract: Provided is a magenta toner having a magenta toner particle containing a binder resin, a colorant, a wax, a wax dispersant, and a crystalline polyester, wherein the wax dispersant is a graft polymer in which a styrene acrylic resin is grafted to a hydrocarbon compound, and the styrene acrylic resin has a monomer unit having a saturated alicyclic group, the colorant contains C.I. Pigment Red 32, and when observing a cross-section of the magenta toner particle using a transmission electron microscope (TEM), crystals of the crystalline polyester are dispersed in the cross-section, and the number average value of maximum lengths of the crystals is 50 nm or less.
    Type: Application
    Filed: November 29, 2018
    Publication date: June 6, 2019
    Inventors: Takeshi Ohtsu, Yosuke Iwasaki, Wakiko Katsumata, Koh Ishigami, Masaharu Miura, Kentaro Kamae, Kenta Mitsuiki, Ryuichiro Matsuo, Yuichi Mizo
  • Patent number: 10234777
    Abstract: A toner is provided, which is obtained by heat treating a toner particle containing a crystalline polyester resin, an amorphous polyester resin, a hydrocarbon wax and a wax dispersant, wherein the crystalline polyester resin is a hybrid resin having crystalline polyester segments and amorphous vinyl segments, and a mass ratio of crystalline polyester segments and amorphous vinyl segments in the crystalline polyester resin (crystalline segments/amorphous segments) is 70/30 to 98/2.
    Type: Grant
    Filed: March 13, 2017
    Date of Patent: March 19, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Takeshi Ohtsu, Kentaro Kamae, Ryuichiro Matsuo, Yosuke Iwasaki, Wakiko Katsumata, Kenta Mitsuiki, Masaharu Miura, Koh Ishigami, Yuichi Mizo
  • Patent number: 10216108
    Abstract: A toner production method including: a melt-kneading step of melt-kneading a resin composition including a binder resin, a colorant, a wax, and a wax dispersant to obtain a melt-kneaded product; and a pulverizing step of pulverizing the melt-kneaded product. Where the temperature of the melt-kneaded product at the end of the melt-kneading step is Tk (° C.), and the softening point of the wax dispersant is Tm (° C.), the relationship of ?18?[Tk?Tm]?10 is satisfied. The wax dispersant is a polymer in which a styrene acrylic polymer is graft-polymerized to a polyolefin. The styrene acrylic polymer has a monomer unit derived from ?-methylstyrene and a monomer unit derived from a cycloalkyl (meth)acrylate.
    Type: Grant
    Filed: August 10, 2017
    Date of Patent: February 26, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yosuke Iwasaki, Takeshi Ohtsu, Kentaro Kamae, Ryuichiro Matsuo, Wakiko Katsumata, Kenta Mitsuiki, Masaharu Miura, Koh Ishigami, Yuichi Mizo
  • Patent number: 10133201
    Abstract: Provided is a toner including a toner particle containing an amorphous resin, a colorant, a release agent, and a crystalline resin, wherein, when ?0.01 represents the extensional viscosity of the toner at a Hencky strain at 90° C. of 0.01 and ?0.69 represents the extensional viscosity of the toner at a Hencky strain at 90° C. of 0.69, ?0.01 and ?0.69 satisfy the relationships of the following formulas (1) and (2): 3.0×104 Pa??0.01?2.0×105 Pa??formula (1) 2.0?[?0.69/?0.01].
    Type: Grant
    Filed: July 27, 2017
    Date of Patent: November 20, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kentaro Kamae, Ryuichiro Matsuo, Yosuke Iwasaki, Wakiko Katsumata, Kenta Mitsuiki, Takeshi Ohtsu, Masaharu Miura, Koh Ishigami, Yuichi Mizo
  • Publication number: 20180275540
    Abstract: A toner comprising a toner particle and inorganic fine particles present on the surface of the toner particle, wherein particle diameter numerical distribution of the inorganic fine particles on the toner particle surface has a peak A1 and B1 present in specific particle diameter ranges, the proportion of inorganic fine particles having a particle diameter of 5 nm to 30 nm is not more than 10 number %, after the toner has been subjected to a water wash treatment, the particle diameter numerical distribution of the of the primary particles of the inorganic fine particles on the toner particle surface has a peak A2 and B2 in specific particle diameter ranges; and HB1, which is a peak value of the peak B1, and HB2, which is a peak value of the peak B2, satisfy a specific relationship.
    Type: Application
    Filed: March 13, 2018
    Publication date: September 27, 2018
    Inventors: Ryuichiro Matsuo, Masaharu Miura, Yosuke Iwasaki, Wakiko Katsumata, Kenta Mitsuiki, Kentaro Kamae, Takeshi Ohtsu, Koh Ishigami, Yuichi Mizo
  • Patent number: 10012918
    Abstract: A toner having a toner particle that is produced through a step of melt-kneading a resin composition containing a binder resin, a colorant, a hydrocarbon wax, and a wax dispersing agent, cooling the obtained kneaded material, pulverizing the obtained cooled material, and heat treating the resulting resin particles, wherein the wax dispersing agent is a polymer provided by graft polymerizing a styrene-acrylic polymer onto a polypropylene, the styrene-acrylic polymer is a polymer having a monomer unit derived from a cycloalkyl (meth)acrylate, and specific relationships are satisfied where Mp(p) is the melting point (° C.) of the polypropylene and Mp(w) is the melting point (° C.) of the hydrocarbon wax.
    Type: Grant
    Filed: February 14, 2017
    Date of Patent: July 3, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Koh Ishigami, Takeshi Ohtsu, Kentaro Kamae, Ryuichiro Matsuo, Yosuke Iwasaki, Wakiko Katsumata, Kenta Mitsuiki, Masaharu Miura, Yuichi Mizo