Patents by Inventor Shuntaro Watanabe

Shuntaro Watanabe 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: 20210080846
    Abstract: A toner comprising a toner particle including a binder resin, wherein in a temperature T (° C.)-storage elastic modulus G? (Pa) curve obtained by measuring the toner with a rheometer, a storage elastic modulus G? (80° C.) at 80° C. is from 2.0×103 Pa to 2.0×105 Pa; and a local minimum value of a change amount (dG?/dT) of a storage elastic modulus G? in a range of 60° C. to 80° C. with respect to a temperature T is ?1.0×106 or less, and when the temperature of the toner is raised, where a projected area of the toner at 80° C. is S1 (?m2), a radius of the projected area of the toner at 80° C. is R1 (?m), and a projected area of the toner at 120° C. is S2 (?m2), the S1, R1 and S2 satisfy a following formula (1): S2/S1×1/R1?0.22.
    Type: Application
    Filed: September 4, 2020
    Publication date: March 18, 2021
    Inventors: Takuya Mizuguchi, Yoshitaka Suzumura, Hiroyuki Tomono, Osamu Matsushita, Shuntaro Watanabe, Hiroki Akiyama, Hiroki Kagawa
  • Publication number: 20210055667
    Abstract: A toner comprising a resin that contains an amorphous segment and a crystalline segment as a binder resin, wherein a proportion of a tetrahydrofuran-insoluble matter of a resin component is from 40% by mass to 80% by mass; in differential scanning calorimeter measurement of the tetrahydrofuran-insoluble matter, where a temperature of a maximum endothermic peak is denoted by Tm [° C.] and an endothermic quantity is denoted by H(I) [J/g], the following formulas (1) and (2) are satisfied: 55.0?Tm?80.0??(1) 10.0?H(I)?80.0??(2).
    Type: Application
    Filed: August 7, 2020
    Publication date: February 25, 2021
    Inventors: Shuntaro Watanabe, Hiroki Akiyama, Hiroki Kagawa
  • Patent number: 10768540
    Abstract: Provided is an external additive having a resin particle containing a crystalline resin, and an inorganic fine particle containing a metal atom, the inorganic fine particle being embedded in the resin particle, wherein part of the inorganic fine particle being exposed on a surface of the resin particle, the maximum endothermic peak temperature of the external additive during a first temperature rise is from 50.0° C. to 120° C., the shape factor SF-2 of the external additive is from 110 to 150, and the external additive satisfies following formulae (1) and (2) below, in which Za (mass %) is the percentage content of a metal atom contained in the inorganic fine particle on the surface of the external additive in X-ray photoelectron spectroscopy, and Zb (mass %) is the percentage content of the metal atom in thermogravimetric analysis of the external additive, Za?15??(1), and Za/Zb?0.
    Type: Grant
    Filed: February 11, 2019
    Date of Patent: September 8, 2020
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shuntaro Watanabe, Tatsuya Saeki, Atsuhiko Ohmori, Shuhei Moribe, Hiroki Akiyama, Kazumichi Nakahama, Katsuhisa Yamazaki
  • Patent number: 10747134
    Abstract: An external toner additive having a resin fine particle containing a crystalline resin and an inorganic fine particle embedded in the resin fine particle, wherein part of the inorganic fine particle is exposed on the surface of the resin fine particle, and in differential scanning calorimetry of the external toner additive, the maximum endothermic peak temperature T1 (° C.) during a first temperature increase and the maximum exothermic peak temperature T2 (° C.) during a first temperature decrease satisfy the formulae (1) to (3) below, with measurement performed between ?40° C. and 150° C. at a rate of increase of 10° C./min during the first temperature increase and between 150° C. and ?40° C. at a rate of decrease in temperature of 10° C./min during the first temperature decrease: T1-T2?40.0??(1) 50.0?T1?120.0??(2) 10.0?T2?80.0??(3).
    Type: Grant
    Filed: January 28, 2019
    Date of Patent: August 18, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Shuntaro Watanabe, Tatsuya Saeki, Atsuhiko Ohmori, Shuhei Moribe, Hiroki Akiyama, Kazumichi Nakahama, Katsuhisa Yamazaki
  • Publication number: 20190384192
    Abstract: Provided is a magnetic toner having a toner particle containing a binder resin and a magnetic body, wherein the binder resin contains a polymer A having a first monomer unit and a second monomer unit, the first polymerizable monomer is at least one selected from the group consisting of the (meth)acrylic acid esters having C18-36 alkyl groups, a content of the first monomer unit and a content of the second monomer unit based on the total moles of all monomer units in the polymer A are respectively 5.0 to 60.0 mol % and 20.0 to 95.0 mol %, and assuming that an SP value of the first monomer unit and the second monomer unit are taken as SP11 (J/cm3)0.5 and SP21(J/cm3)0.5, respectively, 3.00?(SP21?SP11)?25.00 is satisfied, and an oil absorption of the magnetic body is 5 to 40 ml/100 g.
    Type: Application
    Filed: June 12, 2019
    Publication date: December 19, 2019
    Inventors: Hiroki Kagawa, Shuntaro Watanabe, Hiroki Akiyama, Tatsuya Saeki, Takashi Matsui
  • Publication number: 20190384195
    Abstract: A toner comprising a toner particle containing a binder resin, the storage elastic modulus Gt? (150) of the toner at 150° C. is at least 1.0×104 Pa, 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 different from the first polymerizable monomer, the first polymerizable monomer is selected from specific (meth)acrylic acid esters, the contents of the first monomer unit and second monomer unit in the polymer A are within specific ranges, and the SP values of the first monomer unit and second monomer unit are within specific ranges.
    Type: Application
    Filed: June 12, 2019
    Publication date: December 19, 2019
    Inventors: Tatsuya Saeki, Shuntaro Watanabe, Hiroki Akiyama, Hiroki Kagawa, Takashi Matsui
  • Patent number: 10409180
    Abstract: A method of producing a toner including the steps of: mixing resin fine particles, an organic solvent, and a resin R with a dispersion medium containing carbon dioxide, to prepare a dispersion of resin R-containing droplets; and removing the organic solvent by flowing carbon dioxide, wherein the resin fine particles contain one or more resins that have a partial structure A, B, and C, and are soluble in chloroform; the SP value of the partial structure A, the resin R, and the partial structure B satisfy particular relationships; a resin A constituted of the partial structure A and a resin B constituted of the partial structure B are soluble in the organic solvent; and a resin C constituted of the partial structure C is insoluble in the organic solvent.
    Type: Grant
    Filed: February 6, 2018
    Date of Patent: September 10, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Shinnosuke Koji, Sakae Suda, Yusuke Kosaki, Shohei Fukuya, Tetsuya Kinumatsu, Kenji Aoki, Toshifumi Mori, Shuntaro Watanabe, Noritaka Toyoizumi, Atsushi Tani, Kazumichi Nakahama
  • Publication number: 20190250526
    Abstract: Provided is an external additive having a resin particle containing a crystalline resin, and an inorganic fine particle containing a metal atom, the inorganic fine particle being embedded in the resin particle, wherein part of the inorganic fine particle being exposed on a surface of the resin particle, the maximum endothermic peak temperature of the external additive during a first temperature rise is from 50.0° C. to 120° C., the shape factor SF-2 of the external additive is from 110 to 150, and the external additive satisfies following formulae (1) and (2) below, in which Za (mass%) is the percentage content of a metal atom contained in the inorganic fine particle on the surface of the external additive in X-ray photoelectron spectroscopy, and Zb (mass%) is the percentage content of the metal atom in thermogravimetric analysis of the external additive, Za>15??(1), and Za/Zb?0.
    Type: Application
    Filed: February 11, 2019
    Publication date: August 15, 2019
    Inventors: Shuntaro Watanabe, Tatsuya Saeki, Atsuhiko Ohmori, Shuhei Moribe, Hiroki Akiyama, Kazumichi Nakahama, Katsuhisa Yamazaki
  • Publication number: 20190250528
    Abstract: An external toner additive having a resin fine particle containing a crystalline resin and an inorganic fine particle embedded in the resin fine particle, wherein part of the inorganic fine particle is exposed on the surface of the resin fine particle, and in differential scanning calorimetry of the external toner additive, the maximum endothermic peak temperature T1 (° C.) during a first temperature increase and the maximum exothermic peak temperature T2 (° C.) during a first temperature decrease satisfy the formulae (1) to (3) below, with measurement performed between ?40° C. and 150° C. at a rate of increase of 10° C./min during the first temperature increase and between 150° C. and ?40° C. at a rate of decrease in temperature of 10° C./min during the first temperature decrease: T1-T2?40.0??(1) 50.0?T1?120.0??(2) 10.0?T2?80.0??(3).
    Type: Application
    Filed: January 28, 2019
    Publication date: August 15, 2019
    Inventors: Shuntaro Watanabe, Tatsuya Saeki, Atsuhiko Ohmori, Shuhei Moribe, Hiroki Akiyama, Kazumichi Nakahama, Katsuhisa Yamazaki
  • Patent number: 10078280
    Abstract: A method for producing a toner particle include: (a) mixing a binder resin A, resin fine particles containing a resin B, a resin C, an organic solvent, and carbon dioxide, thereby forming a droplet of a resin solution containing the binder resin A, covered with the resin fine particles; (b) applying a pressure by introducing carbon dioxide, thereby precipitating the resin C at the surface of the droplet; and (c) passing carbon dioxide so as to remove the organic solvent from the droplet with the carbon dioxide. The resin C has an organic polysiloxane structure and a weight average molecular weight of 50,000 to 500,000. The ratio of the weight average molecular weight to the number average molecular weight of the resin C is not more than 5.0. The proportion of the resin C to the rein fine particles is 5.0% by mass to 50.0% by mass.
    Type: Grant
    Filed: June 14, 2017
    Date of Patent: September 18, 2018
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kenji Aoki, Yusuke Kosaki, Noritaka Toyoizumi, Tetsuya Kinumatsu, Toshifumi Mori, Sakae Suda, Shinnosuke Koji, Shuntaro Watanabe, Kazumichi Nakahama, Atsushi Tani, Takashige Kasuya
  • Publication number: 20180231901
    Abstract: A method of producing a toner including the steps of: mixing resin fine particles, an organic solvent, and a resin R with a dispersion medium containing carbon dioxide, to prepare a dispersion of resin R-containing droplets; and removing the organic solvent by flowing carbon dioxide, wherein the resin fine particles contain one or more resins that have a partial structure A, B, and C, and are soluble in chloroform; the SP value of the partial structure A, the resin R, and the partial structure B satisfy particular relationships; a resin A constituted of the partial structure A and a resin B constituted of the partial structure B are soluble in the organic solvent; and a resin C constituted of the partial structure C is insoluble in the organic solvent.
    Type: Application
    Filed: February 6, 2018
    Publication date: August 16, 2018
    Inventors: Shinnosuke Koji, Sakae Suda, Yusuke Kosaki, Shohei Fukuya, Tetsuya Kinumatsu, Kenji Aoki, Toshifumi Mori, Shuntaro Watanabe, Noritaka Toyoizumi, Atsushi Tani, Kazumichi Nakahama
  • Patent number: 9964876
    Abstract: A toner includes toner particles which contain a binder resin, a colorant, a wax, and a resin A having an organic polysiloxane structure; the amount of Si atoms of the toner particles is 4.5 to 10.0; in an analysis of a cross-section of each toner particle, in a surface layer region R from the periphery of the cross-section of the toner particle to the inside at a distance of 10.0% of the particle diameter in the cross-section of the toner particle, the content of Si atoms derived from the organic polysiloxane structure is 90.0% or more with respect to the total amount of Si atoms contained in the toner particle; and in a line analysis along a straight line between the periphery of the surface layer region R and a gravity center of the cross-section, an intensity count of Si atoms in the toner particle satisfies formula Si0>Si1>Si2>Si3?0.
    Type: Grant
    Filed: July 24, 2017
    Date of Patent: May 8, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Noritaka Toyoizumi, Yusuke Kosaki, Tetsuya Kinumatsu, Kenji Aoki, Toshifumi Mori, Sakae Suda, Shinnosuke Koji, Shuntaro Watanabe, Kazumichi Nakahama, Atsushi Tani, Takashige Kasuya
  • Publication number: 20180031988
    Abstract: A toner includes toner particles which contain a binder resin, a colorant, a wax, and a resin A having an organic polysiloxane structure; the amount of Si atoms of the toner particles is 4.5 to 10.0; in an analysis of a cross-section of each toner particle, in a surface layer region R from the periphery of the cross-section of the toner particle to the inside at a distance of 10.0% of the particle diameter in the cross-section of the toner particle, the content of Si atoms derived from the organic polysiloxane structure is 90.0% or more with respect to the total amount of Si atoms contained in the toner particle; and in a line analysis along a straight line between the periphery of the surface layer region R and a gravity center of the cross-section, an intensity count of Si atoms in the toner particle satisfies formula Si0>Si1>Si2>Si3?0.
    Type: Application
    Filed: July 24, 2017
    Publication date: February 1, 2018
    Inventors: Noritaka Toyoizumi, Yusuke Kosaki, Tetsuya Kinumatsu, Kenji Aoki, Toshifumi Mori, Sakae Suda, Shinnosuke Koji, Shuntaro Watanabe, Kazumichi Nakahama, Atsushi Tani, Takashige Kasuya
  • Patent number: 9869943
    Abstract: A method of producing a toner containing a toner particle, including the steps of: a) preparing a resin solution by mixing a resin A and an organic solvent, b) mixing the resin solution, a resin fine particle containing a resin B, and a dispersion medium to form a droplet of the resin solution whose surface has been covered with the resin fine particle, and c) removing the organic solvent in the droplet, in which the resin B is a polymer of a monomer composition containing a monomer X having polymerizable unsaturated groups at the both ends; the monomer X has a peak molecular weight of 5,000 to 50,000; the content of the monomer X is 0.10% to 3.00% by mol; and the following formula (1) is satisfied, |SPX?SPA|?2.0??(1) where SPA and SPX represent solubility parameters of the resin A and the monomer X, respectively.
    Type: Grant
    Filed: October 12, 2016
    Date of Patent: January 16, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kenji Aoki, Yusuke Kosaki, Tetsuya Kinumatsu, Shuntaro Watanabe, Noritaka Toyoizumi, Atsushi Tani, Takashige Kasuya
  • Patent number: 9857713
    Abstract: Provided is a toner, comprising a toner particle having a core-shell structure composed of a core particle and a shell phase on a surface of the core particle, the core particle containing a resin X and a colorant, the shell phase being derived from a resin fine particle containing a resin Y, in which a relationship among a SP value of the resin X, a SP value of the resin Y, and a SP value of an organic solvent falls within a specific range, and a relationship between a number-average particle diameter of the resin fine particle when the resin fine particle is dispersed in water and a number-average particle diameter of the resin fine particle when the resin fine particle is dispersed in the organic solvent falls within a specific range.
    Type: Grant
    Filed: December 17, 2015
    Date of Patent: January 2, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yusuke Kosaki, Tetsuya Kinumatsu, Kenji Aoki, Noritaka Toyoizumi, Shuntaro Watanabe, Takaaki Kaya, Atsushi Tani, Takashige Kasuya, Kazumichi Nakahama, Shinnosuke Koji
  • Publication number: 20170363979
    Abstract: A method for producing a toner particle include: (a) mixing a binder resin A, resin fine particles containing a resin B, a resin C, an organic solvent, and carbon dioxide, thereby forming a droplet of a resin solution containing the binder resin A, covered with the resin fine particles; (b) applying a pressure by introducing carbon dioxide, thereby precipitating the resin C at the surface of the droplet; and (c) passing carbon dioxide so as to remove the organic solvent from the droplet with the carbon dioxide. The resin C has an organic polysiloxane structure and a weight average molecular weight of 50,000 to 500,000. The ratio of the weight average molecular weight to the number average molecular weight of the resin C is not more than 5.0. The proportion of the resin C to the rein fine particles is 5.0% by mass to 50.0% by mass.
    Type: Application
    Filed: June 14, 2017
    Publication date: December 21, 2017
    Inventors: Kenji Aoki, Yusuke Kosaki, Noritaka Toyoizumi, Tetsuya Kinumatsu, Toshifumi Mori, Sakae Suda, Shinnosuke Koji, Shuntaro Watanabe, Kazumichi Nakahama, Atsushi Tani, Takashige Kasuya
  • Patent number: 9823595
    Abstract: Provided is a toner including toner particle, the toner particle having a core-shell structure having: a core containing a core resin, a colorant, and a wax; and a shell layer containing a resin “A” on a surface of the core, in which: the resin “A” contains a segment having an organopolysiloxane structure; the toner particle has an amount of Si derived from the organopolysiloxane structure of 6.0 or more and 10.0 or less, the amount of Si being measured by X-ray photoelectron spectroscopy; the resin “A” is a polymer of a monomer composition containing a monomer “a” having two or more polymerizable unsaturated groups in one molecule thereof; and the monomer “a” satisfies the following formula (1). (Xa?1.0)×Ya?3.
    Type: Grant
    Filed: June 8, 2016
    Date of Patent: November 21, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Noritaka Toyoizumi, Yusuke Kosaki, Tetsuya Kinumatsu, Kenji Aoki, Shuntaro Watanabe, Takaaki Kaya, Atsushi Tani, Takashige Kasuya
  • Patent number: 9811016
    Abstract: A toner comprising a toner particle comprising a binder resin that comprises a crystalline resin, wherein the toner satisfies the following formulas (1) and (2) in DSC measurement of the toner, 50.0?Tt?80.0??formula (1) 0.00??HT?t-3/?H?0.20??formula (2) where Tt [° C.] is the peak temperature of the endothermic peak P1, ?H [J/g] is the endothermic quantity from a temperature lower than T?t by 20.0° C. to a temperature higher than T?t by 10.0° C. when T?t [° C.] is the peak temperature of the endothermic peak P 2, and ?H T?t-3 [J/g] is the endothermic quantity from a temperature lower than T?t by 20.0° C. to a temperature lower than T?t by 3.0° C.
    Type: Grant
    Filed: March 16, 2016
    Date of Patent: November 7, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kenji Aoki, Tetsuya Kinumatsu, Yusuke Kosaki, Shuntaro Watanabe, Noritaka Toyoizumi, Takaaki Kaya, Atsushi Tani, Takashige Kasuya
  • Patent number: 9798262
    Abstract: Provided is a method of producing a toner including the steps of: mixing a resin solution comprising a resin R, a colorant, and an organic solvent, a resin fine particle comprising a resin S containing an element ?, and carbon dioxide to form a droplet having a surface covered with the resin fine particle; introducing carbon dioxide in a liquid state and pressurizing to extract the organic solvent in the droplet; and removing the extracted organic solvent together with the carbon dioxide to provide a toner particle. In the method of producing a toner, when the resin fine particle is treated with the carbon dioxide in a liquid state, a change in amount of the element ? on the surface of the resin fine particle after the treatment as compared to the amount before the treatment falls within a specific range.
    Type: Grant
    Filed: December 17, 2015
    Date of Patent: October 24, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Noritaka Toyoizumi, Yusuke Kosaki, Tetsuya Kinumatsu, Kenji Aoki, Shuntaro Watanabe, Takaaki Kaya, Atsushi Tani, Kazumichi Nakahama, Shinnosuke Koji, Takashige Kasuya
  • Patent number: 9798256
    Abstract: A method of producing a toner includes preparing a resin solution containing a binder resin, a colorant and an organic solvent; forming a droplet, a surface of the droplet being covered with a resin fine particle L1; introducing a resin fine particle L2; pressuring by introducing carbon dioxide, and extracting the organic solvent in the droplet; and obtaining the toner particle by removing the carbon dioxide together with the extracted organic solvent, wherein the SP value of the resin R1 constituting the resin fine particle L1 and the SP value of the resin R2 constituting the resin fine particle L2 are each within a specific range.
    Type: Grant
    Filed: June 9, 2016
    Date of Patent: October 24, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yusuke Kosaki, Noritaka Toyoizumi, Tetsuya Kinumatsu, Kenji Aoki, Shuntaro Watanabe, Takaaki Kaya, Atsushi Tani, Takashige Kasuya