Patents by Inventor Koh Ishigami

Koh Ishigami 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: 20240118639
    Abstract: A thermal treatment apparatus includes a treatment tank including a treatment chamber to perform thermal treatment on toner particles; a toner particle supply unit configured to supply toner particles into the treatment chamber; and a hot air supply unit including a supply port to supply hot air into the treatment chamber. The supply port of the hot air supply unit is disposed on a ceiling of the treatment chamber. The treatment tank further includes: a columnar member that is vertically disposed at the center inside of the treatment chamber; and a protruded member that is disposed at an upper end of the columnar member and has an approximately conical shape protruding toward the ceiling. The columnar member has a cylindrical shape and a radius of curvature RCP (mm) of an upper end edge in a vertical cross-section thereof is 5<RCP<75.
    Type: Application
    Filed: September 29, 2023
    Publication date: April 11, 2024
    Inventors: TAKESHI OHTSU, KOH ISHIGAMI, KOUICHIROU OCHI, YOSUKE IWASAKI, DAISUKE YAMASHITA, HISASUKE KAJIHARA
  • Publication number: 20230375953
    Abstract: Provided is a toner that expresses all of low-temperature fixability, transferability, and scratch resistance at high levels. The toner is a toner including a toner particle containing a binder resin, a wax, and an inorganic fine particle, wherein when an outflow start temperature measured with the toner is represented by T1 (° C.), the inorganic fine particle always has a thermal expansion coefficient of ?0.1×10?6 (/K) or less in a temperature range of from 30° C. or more to T1° C. or less, the thermal expansion coefficient being determined by X-ray diffraction and wherein a content of the wax is 3.0 mass % or more and 20.0 mass % or less with respect to a mass of the toner particle.
    Type: Application
    Filed: May 11, 2023
    Publication date: November 23, 2023
    Inventors: JUNICHI TAMURA, YOSUKE IWASAKI, TAKESHI OHTSU, RYUJI OKAMURA, DAISUKE YAMASHITA, KOH ISHIGAMI
  • 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: 11698594
    Abstract: A toner including a toner particle comprising a binder resin and a crystalline polyester, wherein the binder resin contains a polyester having a structure represented by the following formula (1): in formula (1), Rs each independently represent hydrogen, a methyl group, or a phenyl group; A represents a polyester segment; B represents a polyester segment or any functional group selected from the group consisting of —R1OH, —R1COOH, and —R1NH2 wherein R1 represents a single bond or a C1-4 alkylene group; and the average repeat number n is 10 to 80.
    Type: Grant
    Filed: April 6, 2021
    Date of Patent: July 11, 2023
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Toru Takahashi, Nobuyoshi Sugahara, Hitoshi Sano, Kazunari Ooyama, Yuu Nishimura, Kohji Takenaka, Koh Ishigami
  • 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: 20220252995
    Abstract: A magnetic toner comprising a toner particle comprising a binder resin and magnetic iron oxide particles, wherein a content of the magnetic iron oxide particles in the magnetic toner is 30 to 45 mass %, the magnetic iron oxide particles contain (i) spherical magnetic iron oxide particles and (ii) at least one selected from the group consisting of hexahedral magnetic iron oxide particles and octahedral magnetic iron oxide particles, and a content of the spherical magnetic iron oxide particles in the magnetic iron oxide particles is 1.0 to 9.0% by number.
    Type: Application
    Filed: January 21, 2022
    Publication date: August 11, 2022
    Inventors: Daisuke Tsujimoto, Koh Ishigami, Junichi Tamura, Hiroki Watanabe
  • Publication number: 20220050398
    Abstract: A toner includes toner particles containing a binder resin, a colorant, and inorganic fine particles, in which in a depth profile of an element distribution in a depth region from the outermost surface of a particle to a depth of 500 nm the depth profile being obtained by an element analysis performed by X-ray photoelectron spectroscopy using the toner as a sample, two or more minimum points of a concentration of a carbon element in the depth region exist, a concentration of an inorganic element becomes a maximum value at a depth position corresponding to each of the minimum points, and the inorganic element is an element derived from the inorganic fine particle.
    Type: Application
    Filed: July 22, 2021
    Publication date: February 17, 2022
    Inventors: Kazunari Ooyama, Yuu Nishimura, Nobuyoshi Sugahara, Hitoshi Sano, Toru Takahashi, Kazuki Murata, Daisuke Tsujimoto, Koh Ishigami, Shin Kitamura, Takaho Shibata, Ryo Nakajima
  • 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: 20210302853
    Abstract: A toner comprising a toner particle containing a binder resin and a polymer A, wherein the binder resin contains a polyester resin having a specific structure, the polymer A has a first monomer unit derived from a specific (meth)acrylic acid ester and a second monomer unit different from the first monomer unit, a content ratio of the first monomer unit in the polymer A is 5.0 mol % to 60.0 mol % while a content ratio of the second monomer unit in the polymer A is 20.0 mol % to 95.0 mol %, and the SP value of the first monomer unit, the SP value of the second monomer unit, and the SP value of a silicone segment contained in the specific structure satisfy a specific relationship.
    Type: Application
    Filed: March 24, 2021
    Publication date: September 30, 2021
    Inventors: Kazuki Murata, Koh Ishigami, Shin Kitamura, Nobuyoshi Sugahara, Takaho Shibata, Toru Takahashi, Kazunari Ooyama, Yuu Nishimura, Daisuke Tsujimoto, Ryo Nakajima, Hitoshi Sano
  • Publication number: 20210223710
    Abstract: A toner including a toner particle comprising a binder resin and a crystalline polyester, wherein the binder resin contains a polyester having a structure represented by the following formula (1): in formula (1), Rs each independently represent hydrogen, a methyl group, or a phenyl group; A represents a polyester segment; B represents a polyester segment or any functional group selected from the group consisting of —R1OH, —R1COOH, and —R1NH2 wherein R1 represents a single bond or a C1-4 alkylene group; and the average repeat number n is 10 to 80.
    Type: Application
    Filed: April 6, 2021
    Publication date: July 22, 2021
    Inventors: Toru Takahashi, Nobuyoshi Sugahara, Hitoshi Sano, Kazunari Ooyama, Yuu Nishimura, Kohji Takenaka, Koh Ishigami
  • 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: 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: 10775710
    Abstract: A toner includes a toner particle containing a binder resin and a silica fine particle A on a surface of the toner particle, wherein D50 on a number basis of the toner is 3.0 to 6.0 the silica fine particle A is a particle having a particle diameter of 80 to 500 nm, the particle diameter being confirmable by observing the toner with a SEM, and when the average coverage with the silica fine particle A determined by image analysis of a particle group of a small particle diameter side of the toner with a SEM is set to Ss and the average coverage with the silica fine particle A determined by image analysis of a particle group of a large particle diameter side of the toner with a scanning electron microscope is set to S1, Ss is 20 to 70 area %, Ss and S1 satisfy S1/Ss?0.80.
    Type: Grant
    Filed: August 7, 2019
    Date of Patent: September 15, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kentaro Kamae, Ryuji Murayama, Junichi Tamura, Masaharu Miura, Hayato Ida, Takaho Shibata, Koh Ishigami, 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: 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