Patents by Inventor Kentaro Kamae

Kentaro Kamae 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: 20210141315
    Abstract: A magnetic carrier including a magnetic carrier particle having a magnetic core particle and a coating layer of an organosilicon polymer on a surface of the magnetic core particle, wherein the organosilicon polymer has the structure given by formula (T3) below; in 29Si-NMR measurement of the THF-insoluble matter of the organosilicon polymer, the ratio ST3 of the peak area for the structure given by formula (T3) to the total peak area for the organosilicon polymer is at least 0.05; and in the roughness curve measured on the magnetic carrier particle, the mean width (RSm) of the roughness curve elements of the magnetic carrier particle, and the ratio (?/RSm) to this RSm of the standard deviation ? of the width of the region where one period of a protrusion and a recess occurs, are in prescribed ranges. R—Si(O1/2)3??(T3) R in the formula represents a prescribed substituent.
    Type: Application
    Filed: November 9, 2020
    Publication date: May 13, 2021
    Inventors: Kentaro Kamae, Kazuhisa Shirayama, Takeshi Hashimoto, Takeshi Ohtsu, Hayato Ida
  • Patent number: 10969705
    Abstract: Provided is a two-component developer has a toner including a toner particle including a binder resin, and a magnetic carrier, wherein the binder resin includes a polymer A having a first monomer unit derived from a first polymerizable monomer, and a second monomer unit derived from a second polymerizable monomer different from the first polymerizable monomer, the first polymerizable monomer is a specific (meth)acrylic acid ester, a content and an SP value of the first and second monomer units in the polymer A fall within respective specific ranges, the magnetic carrier has a magnetic core and a coating resin of the surface of the magnetic core, the coating resin includes a polymer B having monomer units (a) and (b), each SP value of the monomer units (a) and (b) is a specific value.
    Type: Grant
    Filed: June 12, 2019
    Date of Patent: April 6, 2021
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kazuhisa Shirayama, Hayato Ida, Takeshi Hashimoto, Kentaro Kamae, Takashi Matsui
  • 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: 10859931
    Abstract: A toner having an inorganic fine particle and a toner particle containing a binder resin, wherein the binder resin contains a polymer A having a first monomer unit derived from a first polymerizable monomer and a second monomer unit derived from a second polymerizable monomer that is different from the first polymerizable monomer, the first polymerizable monomer is selected from the (meth)acrylic acid esters each having a C18-36 alkyl group, the content of the first monomer unit in the polymer A is within a specific range, the SP value of the first monomer unit and the SP value of the second monomer unit are in a specific relationship to one another, the inorganic fine particle is surface treated with a compound having an alkyl group, and the volume resistivity of the inorganic fine particle is within a specific range.
    Type: Grant
    Filed: June 12, 2019
    Date of Patent: December 8, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Takeshi Hashimoto, Kentaro Kamae, Kazuhisa Shirayama, Hayato Ida, Takashi Matsui
  • 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: 10656545
    Abstract: A toner has a toner particle including a binder resin, the binder resin includes a polymer A, the polymer A contains a first monomer unit derived from a first polymerizable monomer and a second monomer unit derived from a second polymerizable monomer, the first polymerizable monomer is selected from (meth)acrylic acid esters having an alkyl group having 18 to 36 carbon atoms, the content of the first monomer unit in the polymer A is 5.0 mol % to 60.0 mol %, the content of the second monomer unit in the polymer A is 20.0 mol % to 95.0 mol %, the SP value of the first monomer unit and the SP value of the second monomer unit satisfy a predetermined relationship, the polymer A includes a predetermined polyvalent metal, and the content of the polyvalent metal is 25 ppm to 500 ppm.
    Type: Grant
    Filed: June 12, 2019
    Date of Patent: May 19, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kentaro Kamae, Kazuhisa Shirayama, Takeshi Hashimoto, Hayato Ida, Takashi Matsui
  • 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
  • Patent number: 10514624
    Abstract: A toner comprising: a toner particle that contains a resin component and a silicone compound, wherein the resin component contains at least 50 mass % of olefin resin; a content of the silicone compound is from 1 mass part to 42 mass parts per 100 mass parts of the resin component; a weight-average molecular weight of the silicone compound as measured by GPC is from 1,000 to 25,000; and a content, in a molecular weight distribution of the silicone compound as measured by GPC, of a component having a weight-average molecular weight of not more than 500 is not more than 0.05 mass % of the silicone compound.
    Type: Grant
    Filed: October 1, 2018
    Date of Patent: December 24, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Junichi Tamura, Hayato Ida, Kentaro Kamae, Ryuji Murayama, Takashi Hirasa
  • Publication number: 20190384196
    Abstract: A toner has a toner particle including a binder resin, the binder resin includes a polymer A, the polymer A contains a first monomer unit derived from a first polymerizable monomer and a second monomer unit derived from a second polymerizable monomer, the first polymerizable monomer is selected from (meth)acrylic acid esters having an alkyl group having 18 to 36 carbon atoms, the content of the first monomer unit in the polymer A is 5.0 mol % to 60.0 mol %, the content of the second monomer unit in the polymer A is 20.0 mol % to 95.0 mol %, the SP value of the first monomer unit and the SP value of the second monomer unit satisfy a predetermined relationship, the polymer A includes a predetermined polyvalent metal, and the content of the polyvalent metal is 25 ppm to 500 ppm.
    Type: Application
    Filed: June 12, 2019
    Publication date: December 19, 2019
    Inventors: Kentaro Kamae, Kazuhisa Shirayama, Takeshi Hashimoto, Hayato Ida, Takashi Matsui
  • Publication number: 20190384202
    Abstract: Provided is a two-component developer has a toner including a toner particle including a binder resin, and a magnetic carrier, wherein the binder resin includes a polymer A having a first monomer unit derived from a first polymerizable monomer, and a second monomer unit derived from a second polymerizable monomer different from the first polymerizable monomer, the first polymerizable monomer is a specific (meth)acrylic acid ester, a content and an SP value of the first and second monomer units in the polymer A fall within respective specific ranges, the magnetic carrier has a magnetic core and a coating resin of the surface of the magnetic core, the coating resin includes a polymer B having monomer units (a) and (b), each SP value of the monomer units (a) and (b) is a specific value.
    Type: Application
    Filed: June 12, 2019
    Publication date: December 19, 2019
    Inventors: Kazuhisa Shirayama, Hayato Ida, Takeshi Hashimoto, Kentaro Kamae, Takashi Matsui
  • Publication number: 20190384193
    Abstract: A toner having an inorganic fine particle and a toner particle containing a binder resin, wherein the binder resin contains a polymer A having a first monomer unit derived from a first polymerizable monomer and a second monomer unit derived from a second polymerizable monomer that is different from the first polymerizable monomer, the first polymerizable monomer is selected from the (meth)acrylic acid esters each having a C18-36 alkyl group, the content of the first monomer unit in the polymer A is within a specific range, the SP value of the first monomer unit and the SP value of the second monomer unit are in a specific relationship to one another, the inorganic fine particle is surface treated with a compound having an alkyl group, and the volume resistivity of the inorganic fine particle is within a specific range.
    Type: Application
    Filed: June 12, 2019
    Publication date: December 19, 2019
    Inventors: Takeshi Hashimoto, Kentaro Kamae, Kazuhisa Shirayama, Hayato Ida, Takashi Matsui
  • Patent number: 10451990
    Abstract: A toner comprising a toner particle including a resin component, wherein the resin component includes an olefin copolymer including ester group having specific structures Y1 and Y2 and an olefin copolymer including acid group having an acid value of from 50 mg KOH/g to 300 mg KOH/g, the amount of the olefin copolymer including ester group is 50% by mass or more, the toner particle has a surface layer including the olefin copolymer including acid group which has formed a salt with a metal, the metal is at least one metal selected from the group consisting of Mg, Ca, Sr, Al, and Zn, and the total amount of the metal in the toner is from 25 ppm to 500 ppm.
    Type: Grant
    Filed: September 20, 2018
    Date of Patent: October 22, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kentaro Kamae, Ryuji Murayama, Junichi Tamura, Hayato Ida, Takashi Hirasa
  • 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
  • Patent number: 10353312
    Abstract: A toner including a toner particle having a core-shell structure that has a core formed from a resin 1 and a shell formed from a resin 2 on the surface of the core, wherein the resin 1 contains more than 50 mass % of an ester group-containing olefin-based copolymer, the ester group-containing olefin-based copolymer has a monomer unit Y1 represented by formula (1) below, and at least one type of monomer unit Y2 selected from the group consisting of monomer units represented by formula (2) and formula (3) below, the ester group concentration in the ester group-containing olefin-based copolymer is from 2 mass % to 18 mass %, and the resin 2 is an amorphous resin having a Tg value of from 50° C. to 70° C.
    Type: Grant
    Filed: August 7, 2018
    Date of Patent: July 16, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kentaro Kamae, Ryuji Murayama, Junichi Tamura, Hayato Ida, Takashi Hirasa
  • 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
  • Publication number: 20190113858
    Abstract: A toner comprising a toner particle including a resin component, wherein the resin component includes an olefin copolymer including ester group having specific structures Y1 and Y2 and an olefin copolymer including acid group having an acid value of from 50 mg KOH/g to 300 mg KOH/g, the amount of the olefin copolymer including ester group is 50% by mass or more, the toner particle has a surface layer including the olefin copolymer including acid group which has formed a salt with a metal, the metal is at least one metal selected from the group consisting of Mg, Ca, Sr, Al, and Zn, and the total amount of the metal in the toner is from 25 ppm to 500 ppm.
    Type: Application
    Filed: September 20, 2018
    Publication date: April 18, 2019
    Inventors: Kentaro Kamae, Ryuji Murayama, Junichi Tamura, Hayato Ida, Takashi Hirasa
  • Publication number: 20190107793
    Abstract: A toner comprising: a toner particle that contains a resin component and a silicone compound, wherein the resin component contains at least 50 mass % of olefin resin; a content of the silicone compound is from 1 mass part to 42 mass parts per 100 mass parts of the resin component; a weight-average molecular weight of the silicone compound as measured by GPC is from 1,000 to 25,000; and a content, in a molecular weight distribution of the silicone compound as measured by GPC, of a component having a weight-average molecular weight of not more than 500 is not more than 0.05 mass % of the silicone compound.
    Type: Application
    Filed: October 1, 2018
    Publication date: April 11, 2019
    Inventors: Junichi Tamura, Hayato Ida, Kentaro Kamae, Ryuji Murayama, Takashi Hirasa
  • 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
  • Publication number: 20190049869
    Abstract: A toner including a toner particle having a core-shell structure that has a core formed from a resin 1 and a shell formed from a resin 2 on the surface of the core, wherein the resin 1 contains more than 50 mass % of an ester group-containing olefin-based copolymer, the ester group-containing olefin-based copolymer has a monomer unit Y1 represented by formula (1) below, and at least one type of monomer unit Y2 selected from the group consisting of monomer units represented by formula (2) and formula (3) below, the ester group concentration in the ester group-containing olefin-based copolymer is from 2 mass % to 18 mass %, and the resin 2 is an amorphous resin having a Tg value of from 50° C. to 70° C.
    Type: Application
    Filed: August 7, 2018
    Publication date: February 14, 2019
    Inventors: Kentaro Kamae, Ryuji Murayama, Junichi Tamura, Hayato Ida, Takashi Hirasa