Patents by Inventor Tatsuya Saeki

Tatsuya Saeki 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: 20250116946
    Abstract: A toner having a toner particle including a binder resin and a release agent is provided, wherein the binder resin includes a crystalline resin and an amorphous resin, where in differential scanning calorimetry of the toner, a temperature is raised to obtain a differential scanning calorimetry curve A and then the temperature is lowered to obtain a differential scanning calorimetry curve B, the differential scanning calorimetry curve A has endothermic peaks derived from the crystalline resin and the release agent, the differential scanning calorimetry curve B has exothermic peaks derived from the crystalline resin and the release agent, and these endothermic peaks and exothermic peaks satisfy specific relationships, and a storage elastic modulus G?(TmB) of the toner at the endothermic peak temperature of the crystalline resin is 1.0×105 Pa to 1.0×108 Pa.
    Type: Application
    Filed: October 1, 2024
    Publication date: April 10, 2025
    Inventors: KENTARO YAMAWAKI, KENJI AOKI, TATSUYA SAEKI, YUKI MASUDA
  • Publication number: 20250116945
    Abstract: A toner including a toner particle, wherein a weight-average particle size of the toner is a specific range, a domain-matrix structure in which a domain is dispersed in a matrix is observed on a cross-section of the toner, the matrix includes a crystalline resin A, the domain includes an amorphous resin B, where the domain with a major axis of 300 nm or more is defined as domain C, and the domain with a major axis of 200 nm or less is defined as domain D, a number-average major axis of the domain D is 30 to 150 nm, and a proportion of the cross-section which satisfies (i) and (ii) is 90% or more; (i) 5 to 20 of domains C are present per cross-section and an area ratio of the domain C is 10 to 30%, (ii) the domain D is observed over an entire region in the cross-section.
    Type: Application
    Filed: October 1, 2024
    Publication date: April 10, 2025
    Inventors: KENJI AOKI, TATSUYA SAEKI, YUKI MASUDA, MEGUMI YAMAUCHI, NAOYA ISONO
  • Patent number: 12271150
    Abstract: A toner comprising a toner particle comprising a binder resin, a crystalline material A, and a crystalline material B, wherein the binder resin contains a resin M in an amount of 70 mass % or more relative to the binder resin, the crystalline material A has a melting point of 50.0° C. to 100.0° C., and when, the difference between the SP value of the resin M and material A is designated as ?SPAM, the difference between the SP value of the resin M and crystalline material B is designated as ?SPBM, the difference between the SP value of the crystalline material A and crystalline material B is designated as ?SPAB, the peak molecular weight of the crystalline material A and crystalline material B is designated as MpA and MpB each, the formulae (1) to (3) are satisfied: 50?MpB×?SPBM2?MpA×?SPAM2?450??(1) MpA×?SPAM2?800??(2) ?SPAB?0.26??(3).
    Type: Grant
    Filed: March 4, 2022
    Date of Patent: April 8, 2025
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Taiji Katsura, Shohei Tsuda, Tatsuya Saeki
  • Patent number: 12124212
    Abstract: A toner comprising a toner particle that comprises a core particle comprising a binder resin and a surface layer comprising inorganic fine particles and an organosilicon polymer, wherein the organosilicon polymer has T3 structure represented by R—Si(O1/2)3, in 29Si-NMR measurement of THF insoluble-matter of the toner particle, a proportion of a peak area assigned to the T3 structure relative to a total peak area for the organosilicon polymer is at least 5.0%, and in observation of a cross section of the toner particle using TEM, the toner has a prescribed surface layer thickness, a prescribed number of inorganic fine particles in contact with the core particle in the surface layer, and a prescribed number of inorganic fine particles present in the core particle and not in contact with the surface layer.
    Type: Grant
    Filed: May 25, 2021
    Date of Patent: October 22, 2024
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Shintaro Kawaguchi, Masatake Tanaka, Tatsuya Saeki, Masamichi Sato
  • Publication number: 20240241460
    Abstract: Provided is such a toner that a pigment is dispersed in a toner particle containing a large amount of a crystalline resin, that is, a toner excellent in low-temperature fixability and coloring power, wherein the toner is a toner including a toner particle containing a binder resin, a pigment and a pigment dispersant, wherein the binder resin contains 20.0% by mass or more and 100.0% by mass or less of a crystalline resin, wherein the pigment dispersant is a polymer containing a specific structure that interacts with the pigment and a specific monomer unit that interacts with the crystalline resin.
    Type: Application
    Filed: December 21, 2023
    Publication date: July 18, 2024
    Inventors: NAOYA ISONO, MARIKO YAMASHITA, KENJI AOKI, TATSUYA SAEKI, YUKI MASUDA, MEGUMI MORIYA
  • Publication number: 20240231251
    Abstract: Provided is such a toner that a pigment is dispersed in a toner particle containing a large amount of a crystalline resin, that is, a toner excellent in low-temperature fixability and coloring power. The toner is a toner including a toner particle containing a binder resin, a pigment and a pigment dispersant, wherein the binder resin contains from 20.0% to 100.0% by mass of a crystalline resin, wherein the pigment dispersant is a polymer containing a specific structure that interacts with the pigment and a specific polymer moiety that interacts with the crystalline resin.
    Type: Application
    Filed: December 21, 2023
    Publication date: July 11, 2024
    Inventors: NAOYA ISONO, MARIKO YAMASHITA, KENJI AOKI, TATSUYA SAEKI, YUKI MASUDA, MEGUMI MORIYA
  • Publication number: 20240192618
    Abstract: The toner of the present disclosure comprises a toner particle containing a crystalline resin A, an amorphous resin B, and a release agent, wherein the resin A contains a specific amount of a unit (a) and is contained in a specific amount in the toner, the resin B is contained in a specific amount in the toner, the total content of the resin A and the resin B is 50.0 mass % or more based on the mass of the toner, when a component W having a molecular weight of 5000 or less is isolated from the toner by a certain procedure, the content of the component W is from 0.5 mass % to 20.0 mass % based on the mass of the toner, and the maximum endothermic peak temperature of the component W and the endothermic peak temperature derived from the component W of the toner satisfy a certain requirement.
    Type: Application
    Filed: November 21, 2023
    Publication date: June 13, 2024
    Inventors: YUKI MASUDA, KENJI AOKI, NAOYA ISONO, MARIKO YAMASHITA, TATSUYA SAEKI, MEGUMI MORIYA
  • Publication number: 20240192617
    Abstract: A toner comprises a toner particle, wherein the toner contains a crystalline vinyl resin and an amorphous resin, a weight-average particle diameter of the toner is from 4.0 to 12.0 m, an endothermic quantity ?H derived from the crystalline vinyl resin is from 10 to 70 J/g, and in an analysis by time-of-flight secondary ion mass spectrometry of the toner particle while under sputtering, with A(100) as the ion amount of a specific hydrocarbon over a sputtering time during which 100 nm of a polymethyl methacrylate standard sample film are shaved, the ion amount exhibits one or more peak values, and with A(dmax) as a maximum value from among the peak values, the above A(dmax) and A(100) satisfy the expression below. 1.5?A(dmax)/A(100)?30.
    Type: Application
    Filed: November 6, 2023
    Publication date: June 13, 2024
    Inventors: TATSUYA SAEKI, KENJI AOKI, NAOYA ISONO, MARIKO YAMASHITA, YUKI MASUDA, MEGUMI MORIYA
  • Patent number: 11822286
    Abstract: Provided are a process cartridge and an electrophotographic apparatus each capable of suppressing an image defect (coarseness in a halftone image) caused by toner scattering in association with a charging failure that occurs when the process speed of the electrophotographic apparatus is further increased. The process cartridge includes: an electrophotographic photosensitive member; and a developing unit, which includes a toner storing portion that stores a toner, and which supplies the toner to a surface of the electrophotographic photosensitive member. The electrophotographic photosensitive member includes a surface protective layer containing an electroconductive particle in an appropriate amount, and the volume resistivity of the surface protective layer is controlled. As the toner, there is used a toner in which an organosilicon polymer is present on the surface of a toner particle, a silanol group is present in part of the organosilicon polymer, and the amount of the silanol group is controlled.
    Type: Grant
    Filed: September 27, 2022
    Date of Patent: November 21, 2023
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Takashi Kenmoku, Kunihiko Sekido, Kozue Uratani, Koki Inoue, Tatsuya Saeki
  • Publication number: 20230119795
    Abstract: Provided is a process cartridge that is excellent in initial charge rising performance, and in charge uniformity of a halftone image throughout a long period of time from the start of use until after endurance. Specifically, provided is a process cartridge including: an electrophotographic photosensitive member; a toner; and a developing unit, wherein the toner contains toner particles and an external additive A, the external additive A, and wherein the electrophotographic photosensitive member includes an electroconductive support, a photosensitive layer, and a surface protective layer, wherein the surface protective layer contains electroconductive particles.
    Type: Application
    Filed: September 28, 2022
    Publication date: April 20, 2023
    Inventors: Tatsuya Saeki, Takashi Kenmoku, Kozue Uratani, Koki Inoue, Kunihiko Sekido
  • Publication number: 20230116451
    Abstract: A process cartridge that is detachable from a main body of an electrophotographic apparatus, in which a surface protective layer of an electrophotographic photosensitive member contains an electroconductive particle; the content of the electroconductive particle is 20.0 to 70.0% by volume of the surface protective layer; the surface protective layer has a volume resistivity of 1.0×109 to 1.0×1014 ?·cm; a toner particle has at least one multivalent metal element selected from the group consisting of aluminum, magnesium, calcium, and iron; and a total content of the multivalent metal elements in the toner particle, as measured by coupled induction plasma atomic emission spectrometry (ICP-AES), is 0.10 to 1.25 ?mol/g.
    Type: Application
    Filed: September 30, 2022
    Publication date: April 13, 2023
    Inventors: Kozue Uratani, Takashi Kenmoku, Koki Inoue, Tatsuya Saeki, Kunihiko Sekido
  • Publication number: 20230114583
    Abstract: Provided are a process cartridge and an electrophotographic apparatus each capable of suppressing an image defect (coarseness in a halftone image) caused by toner scattering in association with a charging failure that occurs when the process speed of the electrophotographic apparatus is further increased. The process cartridge includes: an electrophotographic photosensitive member; and a developing unit, which includes a toner storing portion that stores a toner, and which supplies the toner to a surface of the electrophotographic photosensitive member. The electrophotographic photosensitive member includes a surface protective layer containing an electroconductive particle in an appropriate amount, and the volume resistivity of the surface protective layer is controlled. As the toner, there is used a toner in which an organosilicon polymer is present on the surface of a toner particle, a silanol group is present in part of the organosilicon polymer, and the amount of the silanol group is controlled.
    Type: Application
    Filed: September 27, 2022
    Publication date: April 13, 2023
    Inventors: Takashi Kenmoku, Kunihiko Sekido, Kozue Uratani, Koki Inoue, Tatsuya Saeki
  • Publication number: 20230047560
    Abstract: A toner comprising: a toner particle comprising a binder resin; and an external additive on a surface of the toner particle, wherein the binder resin comprises a resin having an ester bond, a peak corresponding to boric acid is detected in ATR-IR analysis of the toner particle in an ATR method using germanium as an ATR crystal, and when a dispersed solution obtained by dispersing the toner in an aqueous solution containing a surfactant is subjected to a detachment treatment A including shaking for 300 seconds using a shaker, and when an external additive detached from the toner by the detachment treatment A is denoted as external additive A, a charge amount of the external additive A using a standard carrier (F81) is ?0.5 ?C/g or less.
    Type: Application
    Filed: July 21, 2022
    Publication date: February 16, 2023
    Inventors: Tatsuya Saeki, Taiji Katsura, Masamichi Sato
  • Publication number: 20230042289
    Abstract: A toner comprising a toner particle comprising a binder resin and boric acid, wherein the toner has an average circularity of 0.95 or more, and the toner has a shape factor SF1 of 105 to 125, and a method for producing to provide a toner with excellent durability for which the improvement of transfer rate with the above physical characteristics.
    Type: Application
    Filed: July 21, 2022
    Publication date: February 9, 2023
    Inventors: Masatake Tanaka, Shohei Tsuda, Tatsuya Saeki
  • Publication number: 20220291601
    Abstract: A toner comprising a toner particle comprising a binder resin, a crystalline material A, and a crystalline material B, wherein the binder resin contains a resin M in an amount of 70 mass % or more relative to the binder resin, the crystalline material A has a melting point of 50.0° C. to 100.0° C., and when, the difference between the SP value of the resin M and material A is designated as ?SPAM, the difference between the SP value of the resin M and crystalline material B is designated as ?SPBM, the difference between the SP value of the crystalline material A and crystalline material B is designated as ?SPAB, the peak molecular weight of the crystalline material A and crystalline material B is designated as MpA and MpB each, the formulae (1) to (3) are satisfied: 50?MpB×?SPBM2?MpA×?SPAM2?450??(1) MpA×?SPAM2?800??(2) ?SPAB?0.
    Type: Application
    Filed: March 4, 2022
    Publication date: September 15, 2022
    Inventors: Taiji Katsura, Shohei Tsuda, Tatsuya Saeki
  • Publication number: 20210373450
    Abstract: A toner comprising a toner particle that comprises a core particle comprising a binder resin and a surface layer comprising inorganic fine particles and an organosilicon polymer, wherein the organosilicon polymer has T3 structure represented by R—Si(O1/2)3, in 29Si-NMR measurement of THF insoluble-matter of the toner particle, a proportion of a peak area assigned to the T3 structure relative to a total peak area for the organosilicon polymer is at least 5.0%, and in observation of a cross section of the toner particle using TEM, the toner has a prescribed surface layer thickness, a prescribed number of inorganic fine particles in contact with the core particle in the surface layer, and a prescribed number of inorganic fine particles present in the core particle and not in contact with the surface layer.
    Type: Application
    Filed: May 25, 2021
    Publication date: December 2, 2021
    Inventors: Shintaro Kawaguchi, Masatake Tanaka, Tatsuya Saeki, Masamichi Sato
  • Patent number: 11112709
    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: Grant
    Filed: June 12, 2019
    Date of Patent: September 7, 2021
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Tatsuya Saeki, Shuntaro Watanabe, Hiroki Akiyama, Hiroki Kagawa, Takashi Matsui
  • Patent number: 11112713
    Abstract: A toner including a toner particle containing a binder resin, wherein the binder resin contains a crystalline resin, and in viscoelasticity measurement of the toner with Tp being a peak temperature of an endothermic peak derived from the crystalline resin in DSC of the toner, given G?(Tp?5, 0.01 Hz) as a storage modulus at a temperature of Tp?5° C. and a frequency of 0.01 Hz, G?(Tp?5, 10 Hz) as a storage modulus at a temperature of Tp?5° C. and a frequency of 10 Hz, and G?(Tp?30, 10 Hz) as a storage modulus at a temperature of Tp?30° C. and a frequency of 10 Hz, the following formulae are satisfied: G?(Tp?30,10 Hz)/G?(Tp?5,0.01 Hz)?1.40 G?(Tp?5,10 Hz)/G?(Tp?5,0.01 Hz)?2.20.
    Type: Grant
    Filed: February 27, 2020
    Date of Patent: September 7, 2021
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Hiroki Akiyama, Shuhei Moribe, Hiroyuki Tomono, Tatsuya Saeki, Hiroki Kagawa, Atsuhiko Ohmori, Katsuhisa Yamazaki
  • Patent number: 10969704
    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: Grant
    Filed: June 12, 2019
    Date of Patent: April 6, 2021
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Hiroki Kagawa, Shuntaro Watanabe, Hiroki Akiyama, Tatsuya Saeki, Takashi Matsui
  • Patent number: 10960434
    Abstract: According to an embodiment, a coating apparatus includes an application head, a first moving device, a second moving device, a feeding device, and a suction device. The application head is opposed to a coating surface of a target with a predetermined distance, and forms a meniscus pillar of a coating material between the application head and the coating surface. The first moving device moves the application head. The second moving device moves the application head. The feeding device feeds the coating material between the application head and the coating surface of the target. The suction device sucks the coating material. A distance between the application head and the coating surface is made greater than the predetermined distance, and the coating material is sucked from the meniscus pillar by the suction device.
    Type: Grant
    Filed: March 11, 2016
    Date of Patent: March 30, 2021
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tatsuya Saeki, Hiroaki Kobayashi