Patents by Inventor Yoshitaka Suzumura

Yoshitaka Suzumura 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).

  • Patent number: 11829104
    Abstract: A toner comprising a toner particle comprising a binder resin and a crystalline resin, wherein the binder resin comprises an amorphous resin, when the toner is measured with a temperature-modulated differential scanning calorimeter, at least one endothermic peak derived from the crystalline resin is present in a temperature range from 55.0° C. to 95.0° C. in a total heat flow; and a ratio of an endothermic quantity of the endothermic peak in a reversing heat flow to an endothermic quantity of the endothermic peak in the total heat flow is 50.0% or more, a glass transition temperature Tg1st obtained in the reversing heat flow in a first temperature rise and a glass transition temperature Tg2nd obtained in a reversing heat flow in a second temperature rise satisfy Tg1st?Tg2nd?7.0° C.
    Type: Grant
    Filed: April 27, 2021
    Date of Patent: November 28, 2023
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Takuya Mizuguchi, Yoshitaka Suzumura, Hiroyuki Tomono, Osamu Matsushita, Shotaro Nomura
  • Publication number: 20230037779
    Abstract: A toner comprising a toner particle, and an external additive on a surface of the toner particle, wherein the external additive comprises an agglomerate of fine silica particles surface-treated with silicone oil; when a number-average particle diameter of the agglomerate of the fine silica particles is defined as Rb, the Rb is 12 to 80 nm; when an integrated value of a D unit is defined as A, which obtained when an integrated value of a Q unit is set to 100 in a CP/MAS measurement in a 29Si-solid-state NMR of the fine silica particles, the A is 120 to 300, and the agglomerate of the fine silica particles has a coefficient of variation of particle diameters of 1.00 to 3.00, based on a number of the agglomerate of the fine silica particles.
    Type: Application
    Filed: July 14, 2022
    Publication date: February 9, 2023
    Inventors: Yoshitaka Suzumura, Tomoko Sugita
  • Publication number: 20230015518
    Abstract: A toner comprising a toner particle comprising a binder resin, a nonmagnetic inorganic oxide particle A, and a magnetic iron oxide particle B, wherein a softening point of a chloroform-soluble component of the toner particle is not greater than 90° C.; the nonmagnetic inorganic oxide particle A and the magnetic iron oxide particle B are internally added to the toner particle; the nonmagnetic inorganic oxide particle A comprises as its main component at least one element selected from the group consisting of Si, Mg, Al, Ti, and Sr; a proportion of the inorganic oxide particles having a long diameter of specific length is in specific range; and a value of a ratio of a number-average particle diameter of the long diameter for the nonmagnetic inorganic oxide particle A, to a number-average particle diameter of the long diameter for the magnetic iron oxide particle B, is 5 to 30.
    Type: Application
    Filed: June 24, 2022
    Publication date: January 19, 2023
    Inventors: Dai Nozaki, Yoshitaka Suzumura, Tomohiro Unno
  • Publication number: 20220365457
    Abstract: A toner and a method for producing the toner, wherein; the toner comprising a toner particle comprising a polyester resin, and has a softening point of 150° C. or less; the toner particle has the polyester resin within 100 nm from a surface of the toner particle, and where a value obtained by dividing an amount of counted ions for a structure represented by following formula (A) measured from the surface of the toner particle to a depth of 100 nm by TOF-SIMS by a total amount of counted ions is taken as a standard value, one or more peaks of the standard value are present within a range of 100 nm from the surface of the toner particle, and where A(dmax) denotes a standard value at a maximum peak and A(0) denotes a standard value on the toner particle surface, formula 1.15?A(dmax)/A(0)?5.00 is satisfied.
    Type: Application
    Filed: April 14, 2022
    Publication date: November 17, 2022
    Inventors: Tomohiro Unno, Dai Nozaki, Yoshitaka Suzumura
  • Patent number: 11360405
    Abstract: An electrophotographic apparatus comprising an electrophotographic photosensitive member, a charging device and a developing device, wherein the charging device comprises a conductive member arranged to be capable of contacting the electrophotographic photosensitive member, the conductive layer at the outer surface of the conductive member comprises a matrix and a plurality of domains dispersed in the matrix, at least some of the domains are exposed at the outer surface of the conductive member, the matrix has a volume resistivity R1 of larger than 1.00×1012 ?·cm, the volume resistivity R1 of the matrix is 1.0×105 times or more a volume resistivity R2 of the domains, the developing device comprises the toner comprising a toner particle and a silica fine particle, and a coverage ratio of the toner surface with the silica fine particles is from 62.0% by area to 100.0% by area as determined by X-ray photoelectron spectroscopy.
    Type: Grant
    Filed: October 15, 2020
    Date of Patent: June 14, 2022
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Hiroyuki Tomono, Yoshitaka Suzumura, Takuya Mizuguchi, Osamu Matsushita, Masahiro Kurachi, Kazuhiro Yamauchi, Issei Imamura
  • Patent number: 11360426
    Abstract: An electrophotographic apparatus comprising an electrophotographic photosensitive member, a charging device and a developing device, wherein the charging device comprises a conductive member arranged to be capable of contacting the electrophotographic photosensitive member, a conductive layer of the conductive member comprises a matrix domain structure, at least a part of the domains Dt is exposed at the conductive member outer surface, the matrix has a volume resistivity R1 of larger than 1.00×1012 ?·cm, the domains Dt has a volume resistivity of smaller than R1, the developing device comprises the toner, domains Dc formed of the crystalline material exist in a cross section of the toner, distances between adjacent wall surfaces of the domains Dc is from 30 to 1,100 nm, and a weight-average particle diameter D4 of the toner and distances Dms between adjacent wall surfaces between the domains Dt satisfies D4?Dms.
    Type: Grant
    Filed: October 15, 2020
    Date of Patent: June 14, 2022
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yoshitaka Suzumura, Hiroyuki Tomono, Takuya Mizuguchi, Osamu Matsushita, Shunsuke Matsushita, Masahiro Kurachi, Kazuhiro Yamauchi
  • Publication number: 20220171301
    Abstract: The toner contains a toner particle having a core-shell structure including: a core containing a binder resin and a colorant; and a shell, wherein the toner contains a crystalline material, and the shell contains an amorphous thermoplastic resin; and when SP values of the crystalline material and the amorphous thermoplastic resin, which are calculated by the Fedors method, are defined as SPc (J/cm3)0.5 and SPa (J/cm3)0.5, respectively, the SPc and the SPa (J/cm3) satisfy a particular relationship, and when the toner is observed by SEM after the toner has been subjected to ruthenium staining that treats the toner in an atmosphere of RuO4 gas having 500 Pa for 15 minutes, a ratio S2 (%) of an area occupied by the crystalline material per area of the toner satisfies a particular relationship.
    Type: Application
    Filed: November 15, 2021
    Publication date: June 2, 2022
    Inventors: Yoshitaka Suzumura, Dai Nozaki, Tomohiro Unno
  • Publication number: 20210356878
    Abstract: A toner comprising a toner particle comprising a binder resin and a crystalline resin, wherein the binder resin comprises an amorphous resin, when the toner is measured with a temperature-modulated differential scanning calorimeter, at least one endothermic peak derived from the crystalline resin is present in a temperature range from 55.0° C. to 95.0° C. in a total heat flow; and a ratio of an endothermic quantity of the endothermic peak in a reversing heat flow to an endothermic quantity of the endothermic peak in the total heat flow is 50.0% or more, a glass transition temperature Tg1st obtained in the reversing heat flow in a first temperature rise and a glass transition temperature Tg2nd obtained in a reversing heat flow in a second temperature rise satisfy Tg1st?Tg2nd?7.0° C.
    Type: Application
    Filed: April 27, 2021
    Publication date: November 18, 2021
    Inventors: Takuya Mizuguchi, Yoshitaka Suzumura, Hiroyuki Tomono, Osamu Matsushita, Shotaro Nomura
  • Publication number: 20210116829
    Abstract: An electrophotographic apparatus comprising an electrophotographic photosensitive member, a charging device and a developing device, wherein the charging device comprises a conductive member arranged to be capable of contacting the electrophotographic photosensitive member, the conductive layer at the outer surface of the conductive member comprises a matrix and a plurality of domains dispersed in the matrix, at least some of the domains are exposed at the outer surface of the conductive member, the matrix has a volume resistivity R1 of larger than 1.00×1012 ?·cm, the volume resistivity R1 of the matrix is 1.0×105 times or more a volume resistivity R2 of the domains, the developing device comprises the toner comprising a toner particle and a silica fine particle, and a coverage ratio of the toner surface with the silica fine particles is from 62.0% by area to 100.0% by area as determined by X-ray photoelectron spectroscopy.
    Type: Application
    Filed: October 15, 2020
    Publication date: April 22, 2021
    Inventors: Hiroyuki Tomono, Yoshitaka Suzumura, Takuya Mizuguchi, Osamu Matsushita, Masahiro Kurachi, Kazuhiro Yamauchi, Issei Imamura
  • Publication number: 20210116860
    Abstract: An electrophotographic apparatus comprising an electrophotographic photosensitive member, a charging device and a developing device, wherein the charging device comprises a conductive member arranged to be capable of contacting the electrophotographic photosensitive member, a conductive layer of the conductive member comprises a matrix domain structure, at least a part of the domains Dt is exposed at the conductive member outer surface, the matrix has a volume resistivity R1 of larger than 1.00×1012 ?·cm, the domains Dt has a volume resistivity of smaller than R1, the developing device comprises the toner, domains Dc formed of the crystalline material exist in a cross section of the toner, distances between adjacent wall surfaces of the domains Dc is from 30 to 1,100 nm, and a weight-average particle diameter D4 of the toner and distances Dms between adjacent wall surfaces between the domains Dt satisfies D4?Dms.
    Type: Application
    Filed: October 15, 2020
    Publication date: April 22, 2021
    Inventors: Yoshitaka Suzumura, Hiroyuki Tomono, Takuya Mizuguchi, Osamu Matsushita, Shunsuke Matsushita, Masahiro Kurachi, Kazuhiro Yamauchi
  • 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
  • Patent number: 10698327
    Abstract: Provided is a toner containing a toner particle including a binder resin, a wax, and a colorant. The softening point of the toner is at least 80° C. and not more than 140° C. The average circularity of the toner is at least 0.940. The integrated value of stress in the toner at 150° C. which is measured by using a tackiness tester is at least 78 g·m/sec.
    Type: Grant
    Filed: January 29, 2019
    Date of Patent: June 30, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yuujirou Nagashima, Yusuke Hasegawa, Tomohisa Sano, Yoshitaka Suzumura, Satoshi Arimura, Kozue Uratani
  • Patent number: 10545420
    Abstract: A magnetic toner is provided, which has a magnetic toner particle containing a binder resin, a wax, and a magnetic body, wherein, when Dn is a number-average particle diameter of the toner, CV1 is coefficient of variation of a brightness variance value of the toner in a particle diameter range of Dn ?0.500 to +0.500, and CV2 is coefficient of variation of a brightness variance value of the toner in a particle diameter range of Dn ?1.500 to ?0.500, a relationship CV2/CV1?1.00 is satisfied; an average brightness of the toner in the range of Dn ?0.500 to +0.500 is 30.0 to 60.0; and when, in a cross section of the toner observed using a transmission electron microscope, which is divided with a square grid having a side of 0.8 ?m, coefficient of variation CV3 of an occupied area percentage for the magnetic body is 40.0 to 80.0%.
    Type: Grant
    Filed: June 26, 2018
    Date of Patent: January 28, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Tetsuya Kinumatsu, Yusuke Hasegawa, Kosuke Fukudome, Tomohisa Sano, Kenji Ookubo, Yoshitaka Suzumura, Takuma Ikejiri
  • Patent number: 10310397
    Abstract: The toner has a toner particle that contains a binder resin, a colorant, a release agent, and a crystalline polyester, wherein the release agent contains an ester wax, and the peak top temperature of the maximum endothermic peak of the ester wax as measured with a differential scanning calorimeter is from 65° C. to 85° C., the ester wax satisfies specific conditions and the crystalline polyester satisfies specific conditions, the toner contains from 3.0 parts by mass to 20.0 parts by mass of the crystalline polyester per 100 parts by mass of the binder resin, and the mass ratio of the ester wax to crystalline polyester is from 25/75 to 75/25.
    Type: Grant
    Filed: February 24, 2016
    Date of Patent: June 4, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Tomohisa Sano, Yusuke Hasegawa, Yoshitaka Suzumura, Yuujirou Nagashima, Kozue Uratani
  • Publication number: 20190155181
    Abstract: Provided is a toner containing a toner particle including a binder resin, a wax, and a colorant. The softening point of the toner is at least 80° C. and not more than 140° C. The average circularity of the toner is at least 0.940. The integrated value of stress in the toner at 150° C. which is measured by using a tackiness tester is at least 78 g·m/sec.
    Type: Application
    Filed: January 29, 2019
    Publication date: May 23, 2019
    Inventors: Yuujirou Nagashima, Yusuke Hasegawa, Tomohisa Sano, Yoshitaka Suzumura, Satoshi Arimura, Kozue Uratani
  • Patent number: 10228627
    Abstract: Provided is a toner containing a toner particle including a binder resin, a wax, and a colorant. The softening point of the toner is at least 80° C. and not more than 140° C. The average circularity of the toner is at least 0.940. The integrated value of stress in the toner at 150° C. which is measured by using a tackiness tester is at least 78 g·m/sec.
    Type: Grant
    Filed: November 28, 2016
    Date of Patent: March 12, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yuujirou Nagashima, Yusuke Hasegawa, Tomohisa Sano, Yoshitaka Suzumura, Satoshi Arimura, Kozue Uratani
  • Publication number: 20190011846
    Abstract: A magnetic toner is provided, which has a magnetic toner particle containing a binder resin, a wax, and a magnetic body, wherein, when Dn is a number-average particle diameter of the toner, CV1 is coefficient of variation of a brightness variance value of the toner in a particle diameter range of Dn?0.500 to +0.500, and CV2 is coefficient of variation of a brightness variance value of the toner in a particle diameter range of Dn?1.500 to ?0.500, a relationship CV2/CV1 1.00 is satisfied; an average brightness of the toner in the range of Dn?0.500 to +0.500 is 30.0 to 60.0; and when, in a cross section of the toner observed using a transmission electron microscope, which is divided with a square grid having a side of 0.8 ?m, coefficient of variation CV3 of an occupied area percentage for the magnetic body is 40.0 to 80.0%.
    Type: Application
    Filed: June 26, 2018
    Publication date: January 10, 2019
    Inventors: TETSUYA KINUMATSU, Yusuke Hasegawa, Kasuke Fukudome, Tomohisa Sano, Kenji Ookubo, Yoshitaka Suzumura, Takuma Ikejiri
  • Patent number: 10012923
    Abstract: Provided is a toner including toner particles, each of which contains a binder resin, a colorant, a releasing agent and a crystalline polyester, wherein in an observation of a cross-section each of the toner particles by transmission electron microscopy, specific toner particles each of which has domains of the crystalline polyester and domains of the releasing agent, are present at a ratio of at least 70% by number of the toner particles in the toner, an arithmetic mean of maximum diameters of the domains of the releasing agent is within prescribed range, and the specific toner particles satisfy prescribed conditions.
    Type: Grant
    Filed: April 18, 2017
    Date of Patent: July 3, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Tomohisa Sano, Yusuke Hasegawa, Yoshitaka Suzumura, Satoshi Arimura, Takuma Ikejiri
  • Patent number: 9971264
    Abstract: The magnetic toner contains a magnetic toner particle having a binder resin and a magnetic body, and inorganic fine particles, wherein the average circularity of the magnetic toner is at least 0.955 and, when classifying the inorganic fine particles, in accordance with the fixing strength thereof to the magnetic toner particle and in the sequence of the weakness of the fixing strength, as first inorganic fine particles, second inorganic fine particles, and third inorganic fine particles, the content of the first inorganic fine particles, the ratio of the second inorganic fine particles to the first inorganic fine particles, and the coverage ratio X are in prescribed ranges.
    Type: Grant
    Filed: April 23, 2015
    Date of Patent: May 15, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Tomohisa Sano, Yusuke Hasegawa, Shuichi Hiroko, Yoshitaka Suzumura, Keisuke Tanaka
  • Patent number: 9971262
    Abstract: A magnetic toner containing a magnetic toner particle having a binder resin and a magnetic body, and inorganic fine particles, wherein when the inorganic fine particles are classified as first inorganic fine particles, second inorganic fine particles, and third inorganic fine particles in accordance with fixing strength thereof to the magnetic toner particle and in the sequence of the weakness of the fixing strength, the content of the first inorganic fine particles, the ratio of the second inorganic fine particles to the first inorganic fine particles, and the coverage ratio X of coverage of the magnetic toner surface by the third inorganic fine particles are in prescribed ranges.
    Type: Grant
    Filed: April 23, 2015
    Date of Patent: May 15, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yusuke Hasegawa, Tomohisa Sano, Shuichi Hiroko, Yoshitaka Suzumura, Keisuke Tanaka