Patents by Inventor Daisuke Yoshiba

Daisuke Yoshiba 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: 20200319567
    Abstract: Provided is a positive-charging toner having a toner particle that contains a binder resin, 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, the first polymerizable monomer is at least one selected from the group consisting of (meth)acrylic acid esters having a C18 to C36 alkyl group, the content of the first monomer unit in the polymer A is 5.0 to 60.0 mol % and the content of the second monomer unit is 20.0 to 95.0 mol %, SP11 of the first monomer unit and SP21 of the second monomer unit satisfy 3.00?(SP21?SP11)?25.00, and the work function of the toner is 5.0 to 5.4 V.
    Type: Application
    Filed: June 24, 2020
    Publication date: October 8, 2020
    Inventors: Daisuke Yoshiba, Tomoya Nagaoka, Takashi Matsui
  • Patent number: 10782623
    Abstract: A toner comprising: a toner particle that contains a binder resin and a colorant: and an external additive, wherein (1) the average circularity of the toner is at least 0.960; (2) the fixing ratio of the external additive on the toner particle is from 75% to 100%; and (3) in a differential curve obtained by the differentiation, by load, of a load-displacement curve where the horizontal axis is load (mN) and the vertical axis is displacement (?m), the load-displacement curve being provided by measurement of the strength of the toner by a nanoindentation procedure, a load A that provides a maximum value in the differential curve in a load region from 0.20 mN to 2.30 mN is from 1.15 mN to 1.50 mN.
    Type: Grant
    Filed: July 27, 2018
    Date of Patent: September 22, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Daisuke Yoshiba, Shohei Tsuda, Mariko Yamashita, Kozue Uratani, Ryo Nagata
  • Patent number: 10732529
    Abstract: Provided is a positive-charging toner having a toner particle that contains a binder resin, 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, the first polymerizable monomer is at least one selected from the group consisting of (meth)acrylic acid esters having a C18 to C36 alkyl group, the content of the first monomer unit in the polymer A is 5.0 to 60.0 mol % and the content of the second monomer unit is 20.0 to 95.0 mol %, SP11 of the first monomer unit and SP21 of the second monomer unit satisfy 3.00?(SP21?SP11)?25.00, and the work function of the toner is 5.0 to 5.4 V.
    Type: Grant
    Filed: June 12, 2019
    Date of Patent: August 4, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Daisuke Yoshiba, Tomoya Nagaoka, Takashi Matsui
  • Publication number: 20200166861
    Abstract: A toner comprising a toner particle including a binder resin and a colorant and an external additive, wherein the external additive contains an external additive A having a Feret diameter of 60 to 200 nm, the external additive A is inorganic fine particles or organic-inorganic composite fine particles, adhesion index of the external additive A to the toner is 0.00 to 3.00, and penetration depth b and protrusion height c satisfy Relational expressions (1) and (2) below, where b (nm) denotes penetration depth of the external additive A, at a portion of the external additive A penetrating into the toner particle interior from the surface thereof, and c (nm) denotes a protrusion height of the external additive A at that portion, in an observation of an image resulting from image processing of a cross section of the toner using TEM; 60?b+c?200??(1), 0.15?b/(b+c)?0.30??(2).
    Type: Application
    Filed: January 30, 2020
    Publication date: May 28, 2020
    Inventors: Kozue Uratani, Daisuke Yoshiba, Shohei Tsuda, Tomoya Nagaoka, Mariko Yamashita, Kazuki Kaneko, Ryo Nagata
  • Publication number: 20200081361
    Abstract: A toner including a toner particle containing a polyester resin composition, wherein i) the polyester resin composition contains a specific aliphatic hydrocarbon and a polyester resin having at a terminal a structure derived from at least one of a specific alkyl monoalcohol and a specific alkyl monocarboxylic acid, and ii) the total content of the aliphatic hydrocarbon, the structure derived from the alkyl monoalcohol, and the structure derived from the alkyl monocarboxylic acid is 2.5 to 10.0% by mass, wherein, in the temperature-endothermic quantity curve of the polyester resin composition obtained by DSC, an endothermic peak is present in a specific temperature range and an endothermic quantity for this endothermic peak is 0.10 to 1.90 J/g.
    Type: Application
    Filed: November 12, 2019
    Publication date: March 12, 2020
    Inventors: Daisuke Yoshiba, Hiroki Akiyama, Koji Nishikawa, Shotaro Nomura, Katsuhisa Yamazaki
  • Patent number: 10578990
    Abstract: A toner comprising a toner particle that contains a binder resin and a colorant, wherein (1) an average circularity of the toner is at least 0.960, (2) an onset temperature T? (° C.) of a storage elastic modulus E? of the toner, as determined by a powder dynamic viscoelastic measurement, is from 50° C. to 70° C., and (3) in a differential curve obtained by differentiation, by load, of a load-displacement curve provided by measurement of the strength of the toner by a nanoindentation procedure, with the horizontal axis being load (mN) and the vertical axis being displacement (?m), the load X that provides the maximum value in the differential curve in the load region from 0.20 mN to 2.30 mN is from 1.00 mN to 1.50 mN.
    Type: Grant
    Filed: July 24, 2018
    Date of Patent: March 3, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Shohei Tsuda, Daisuke Yoshiba, Kozue Uratani, Mariko Yamashita
  • Publication number: 20190384194
    Abstract: Provided is a positive-charging toner having a toner particle that contains a binder resin, 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, the first polymerizable monomer is at least one selected from the group consisting of (meth)acrylic acid esters having a C18 to C36 alkyl group, the content of the first monomer unit in the polymer A is 5.0 to 60.0 mol % and the content of the second monomer unit is 20.0 to 95.0 mol %, SP11 of the first monomer unit and SP21 of the second monomer unit satisfy 3.00?(SP21?SP11)?25.00, and the work function of the toner is 5.0 to 5.4 V.
    Type: Application
    Filed: June 12, 2019
    Publication date: December 19, 2019
    Inventors: Daisuke Yoshiba, Tomoya Nagaoka, Takashi Matsui
  • Patent number: 10295921
    Abstract: A toner comprising a toner particle containing a resin and a colorant, wherein, with respect to a temperature-storage elastic modulus curve obtained by powder dynamic viscoelastic measurement on the toner, (I) the relative minimum values for the variation in the storage elastic modulus E? with respect to temperature T in the temperature range of at least 30° C. and not more than 180° C. have a relative minimum value of equal to or less than ?1.00×107 and the relative minimum value on the lowest temperature side is equal to or less than ?1.00×108; (II) the storage elastic modulus E? (50) of the toner at 50° C. is at least 1.00×109 and not more than 9.00×109; and (III) for a storage elastic modulus E? (120) of the toner at 120° C., E? (50) and E? (120) satisfy 1.50?[E? (50)]/[E? (120)]?3.00.
    Type: Grant
    Filed: December 15, 2017
    Date of Patent: May 21, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Atsuhiko Ohmori, Shuhei Moribe, Koji Nishikawa, Kosuke Fukudome, Daisuke Yoshiba, Hiroyuki Tomono, Shotaro Nomura, Sho Kimura, Tatsuya Saeki, Katsuhisa Yamazaki
  • Patent number: 10289016
    Abstract: Provided is a toner having a toner particle including a binder resin and a colorant, wherein the toner has a softening point of at least 100° C. and not more than 150° C., and when Tgt represents a glass transition temperature (° C.) of the toner during a second temperature rise as measured with a DSC, Tgf represents a glass transition temperature (° C.) of a tetrahydrofuran-insoluble matter of the binder resin during a second temperature rise as measured with a DSC, and Tgk represents a glass transition temperature (° C.) of a tetrahydrofuran-soluble matter of the binder resin during a second temperature rise as measured with a DSC, the toner satisfies Tgt>Tgf (1), Tgt>Tgk (2), and 35° C.?Tgf?70° C. (3).
    Type: Grant
    Filed: December 13, 2017
    Date of Patent: May 14, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kosuke Fukudome, Hiroyuki Tomono, Shuhei Moribe, Koji Nishikawa, Daisuke Yoshiba, Shotaro Nomura, Atsuhiko Ohmori, Sho Kimura, Tatsuya Saeki, Katsuhisa Yamazaki
  • Publication number: 20190041762
    Abstract: A toner comprising: a toner particle that contains a binder resin and a colorant: and an external additive, wherein (1) the average circularity of the toner is at least 0.960; (2) the fixing ratio of the external additive on the toner particle is from 75% to 100%; and (3) in a differential curve obtained by the differentiation, by load, of a load-displacement curve where the horizontal axis is load (mN) and the vertical axis is displacement (?m), the load-displacement curve being provided by measurement of the strength of the toner by a nanoindentation procedure, a load A that provides a maximum value in the differential curve in a load region from 0.20 mN to 2.30 mN is from 1.15 mN to 1.50 mN.
    Type: Application
    Filed: July 27, 2018
    Publication date: February 7, 2019
    Inventors: Daisuke Yoshiba, Shohei Tsuda, Mariko Yamashita, Kozue Uratani, Ryo Nagata
  • Publication number: 20190041763
    Abstract: A toner comprising a toner particle that contains a binder resin and a colorant, wherein (1) an average circularity of the toner is at least 0.960, (2) an onset temperature T? (° C.) of a storage elastic modulus E? of the toner, as determined by a powder dynamic viscoelastic measurement, is from 50° C. to 70° C., and (3) in a differential curve obtained by differentiation, by load, of a load-displacement curve provided by measurement of the strength of the toner by a nanoindentation procedure, with the horizontal axis being load (mN) and the vertical axis being displacement (?m), the load X that provides the maximum value in the differential curve in the load region from 0.20 mN to 2.30 mN is from 1.00 mN to 1.50 mN.
    Type: Application
    Filed: July 24, 2018
    Publication date: February 7, 2019
    Inventors: Shohei Tsuda, Daisuke Yoshiba, Kozue Uratani, Mariko Yamashita
  • Patent number: 10162280
    Abstract: A toner having excellent development performance, low-temperature fixation, and high-temperature storage stability is provided. An external additive contained in this toner is an organic-inorganic composite fine particle containing an inorganic fine particle embedded in a resin fine particle. The resin fine particle is made from a resin having a melting point of 60° C. or more and 150° C. or less.
    Type: Grant
    Filed: July 25, 2014
    Date of Patent: December 25, 2018
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kouji Nishikawa, Katsuhisa Yamazaki, Daisuke Yoshiba, Shotaro Nomura, Hiroki Akiyama, Masami Fujimoto
  • Patent number: 10101683
    Abstract: Provided is a toner, including: a toner particle; and an organic-inorganic composite fine particle on a surface of the toner particle, in which the organic-inorganic composite fine particle includes: a resin fine particle; and an inorganic fine particle embedded in the resin fine particle, and part of which is exposed to a surface of the composite fine particle, and in which the composite fine particle satisfies the following relationships: (i) in viscoelasticity measurement of the composite fine particle, when the loss elastic modulus thereof at a temperature T (° C.) is represented by G?T [dN/m2], a change ratio d(Log(G?T))/dT of a common logarithm of the loss elastic modulus has a minimum in a temperature range of from 60° C. to 150° C., and the minimum is less than ?0.10; and (ii) the loss elastic modulus (G?180) thereof at a temperature of 180° C. is 1.0×104 dN/m2 or more and 1.0×107 dN/m2 or less.
    Type: Grant
    Filed: December 18, 2015
    Date of Patent: October 16, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Koji Nishikawa, Shuhei Moribe, Daisuke Yoshiba, Shotaro Nomura, Kosuke Fukudome, Hiroki Akiyama, Yojiro Hotta, Katsuhisa Yamazaki
  • Patent number: 10025212
    Abstract: A toner includes toner particles and an external additive; the external additive includes an external additive A containing fine particles of a crystalline resin or fine particles of a wax; the crystalline resin and the wax each have an urethane bond or an urea bond; and the melting point of the crystalline resin and the melting point of the wax are each from 50° C. to 130° C.
    Type: Grant
    Filed: January 24, 2017
    Date of Patent: July 17, 2018
    Assignee: Canon Kabushiki Kaisha
    Inventors: Koji Nishikawa, Shuhei Moribe, Daisuke Yoshiba, Kosuke Fukudome, Shotaro Nomura, Atsuhiko Ohmori, Katsuhisa Yamazaki
  • Publication number: 20180173126
    Abstract: A toner comprising a toner particle containing a resin and a colorant, wherein, with respect to a temperature-storage elastic modulus curve obtained by powder dynamic viscoelastic measurement on the toner, (I) the relative minimum values for the variation in the storage elastic modulus E? with respect to temperature T in the temperature range of at least 30° C. and not more than 180° C. have a relative minimum value of equal to or less than ?1.00×107 and the relative minimum value on the lowest temperature side is equal to or less than ?1.00×108; (II) the storage elastic modulus E? (50) of the toner at 50° C. is at least 1.00×109 and not more than 9.00×109; and (III) for a storage elastic modulus E? (120) of the toner at 120° C., E? (50) and E? (120) satisfy 1.50?[E? (50)]/[E? (120)]?3.00.
    Type: Application
    Filed: December 15, 2017
    Publication date: June 21, 2018
    Inventors: Atsuhiko Ohmori, Shuhei Moribe, Koji Nishikawa, Kosuke Fukudome, Daisuke Yoshiba, Hiroyuki Tomono, Shotaro Nomura, Sho Kimura, Tatsuya Saeki, Katsuhisa Yamazaki
  • Publication number: 20180173125
    Abstract: Provided is a toner having a toner particle including a binder resin and a colorant, wherein the toner has a softening point of at least 100° C. and not more than 150° C., and when Tgt represents a glass transition temperature (° C.) of the toner during a second temperature rise as measured with a DSC, Tgf represents a glass transition temperature (° C.) of a tetrahydrofuran-insoluble matter of the binder resin during a second temperature rise as measured with a DSC, and Tgk represents a glass transition temperature (° C.) of a tetrahydrofuran-soluble matter of the binder resin during a second temperature rise as measured with a DSC, the toner satisfies Tgt>Tgf (1), Tgt>Tgk (2), and 35° C.?Tgf?70° C. (3).
    Type: Application
    Filed: December 13, 2017
    Publication date: June 21, 2018
    Inventors: Kosuke Fukudome, Hiroyuki Tomono, Shuhei Moribe, Koji Nishikawa, Daisuke Yoshiba, Shotaro Nomura, Atsuhiko Ohmori, Sho Kimura, Tatsuya Saeki, Katsuhisa Yamazaki
  • Patent number: 9971263
    Abstract: Provided is a toner having a toner particle that contains a binder resin and a magnetic particle, wherein the magnetic particle satisfies the following stipulations (i) to (iii): (i) the magnetic particle has a prescribed shape and has a protruded portion on a plane portion thereof, (ii) the magnetic particle has a core particle that contains magnetite and has a coating layer, and (iii) the coating layer contains an iron-containing oxide and at least one of a silicon-containing oxide and an aluminum-containing oxide. In a molecular weight distribution measured on the tetrahydrofuran-soluble matter of the toner, the ratio (Mw/Mn) of a weight-average molecular weight to a number-average molecular weight is at least 10.0.
    Type: Grant
    Filed: December 29, 2016
    Date of Patent: May 15, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kosuke Fukudome, Shuhei Moribe, Koji Nishikawa, Daisuke Yoshiba, Shotaro Nomura, Atsuhiko Ohmori, Sho Kimura, Katsuhisa Yamazaki
  • Patent number: 9931698
    Abstract: A cutting insert for threading of the present invention includes two opposing end surfaces and a peripheral side surface extending therebetween. The peripheral side surface has a first side surface portion and a second side surface portion arranged at different positions in a circumferential direction. A cutting edge is formed at an intersecting ridgeline portion between the first end surface and the first side surface portion and at least a portion of this cutting edge has a shape corresponding to a thread groove. The second side surface portion has an inclined portion which enlarges outward from the side of the first end surface toward the side of the second end surface. This inclined portion is configured to engage with a side wall surface of a tool body so as to prevent floating of the cutting insert.
    Type: Grant
    Filed: May 19, 2014
    Date of Patent: April 3, 2018
    Assignee: TUNGALOY CORPORATION
    Inventors: Daisuke Yoshiba, Eiichi Nunokawa, Atsushi Ogawa
  • Patent number: 9829818
    Abstract: Provided is a toner that uses a crystalline resin, and demonstrates favorable dispersibility of the crystalline resin in the toner, demonstrates superior low-temperature fixability, and is able to inhibit fogging. The toner has a toner particle comprising a resin A, which has a long-chain alkyl group having an average number of carbon atoms of 27 to 50, and a crystalline resin, wherein the SP value (cal/cm3)1/2 of the crystalline resin is 9.00 to 12.00, and in a GC/MS analysis of components that volatize when the toner is heated for 10 minutes at 200° C., the amount of volatile components of saturated hydrocarbons having 30 to 37 carbon atoms is 90 ppm to 260 ppm of toluene equivalent, based on mass.
    Type: Grant
    Filed: September 14, 2015
    Date of Patent: November 28, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Daisuke Yoshiba, Katsuhisa Yamazaki, Koji Nishikawa, Shotaro Nomura, Hiroki Akiyama, Masami Fujimoto
  • Publication number: 20170212441
    Abstract: A toner includes toner particles and an external additive; the external additive includes an external additive A containing fine particles of a crystalline resin or fine particles of a wax; the crystalline resin and the wax each have an urethane bond or an urea bond; and the melting point of the crystalline resin and the melting point of the wax are each from 50° C. to 130° C.
    Type: Application
    Filed: January 24, 2017
    Publication date: July 27, 2017
    Inventors: Koji Nishikawa, Shuhei Moribe, Daisuke Yoshiba, Kosuke Fukudome, Shotaro Nomura, Atsuhiko Ohmori, Katsuhisa Yamazaki