Patents by Inventor Takeshi Kaburagi

Takeshi Kaburagi 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: 11112710
    Abstract: A toner comprising: a toner particle that includes a binder resin, and an external additive, wherein the toner particle includes a polyester resin on the surface; the toner particle includes a polyvalent metal element; where an electrical resistivity of the polyvalent metal element at 20° C. is denoted by A ?·m, and an amount of the polyvalent metal element in the toner particle is denoted by B ?mol/g, a following relationship is satisfied: 0.025×108?(1/A)×B?4.500×108; the external additive includes silica particles; and the silica particles includes spherical silica particles having a number average particle diameter of from 20 nm to 40 nm.
    Type: Grant
    Filed: March 10, 2020
    Date of Patent: September 7, 2021
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kenichi Nakayama, Takeshi Kaburagi, Shintaro Kawaguchi, Shota Amano
  • Publication number: 20200292953
    Abstract: A toner comprising: a toner particle that includes a binder resin, and an external additive, wherein the toner particle includes a polyester resin on the surface; the toner particle includes a polyvalent metal element; where an electrical resistivity of the polyvalent metal element at 20° C. is denoted by A ?·m, and an amount of the polyvalent metal element in the toner particle is denoted by B ?mol/g, a following relationship is satisfied: 0.025×108?(1/A)×B?4.500×108; the external additive includes silica particles; and the silica particles includes spherical silica particles having a number average particle diameter of from 20 nm to 40 nm.
    Type: Application
    Filed: March 10, 2020
    Publication date: September 17, 2020
    Inventors: Kenichi Nakayama, Takeshi Kaburagi, Shintaro Kawaguchi, Shota Amano
  • Patent number: 9829816
    Abstract: Provided is a toner for which the heat-resistant storability and the low-temperature fixability are able to co-exist at higher levels and for which the temporal stability of the low-temperature fixability is also excellent. The toner has a toner particle that contains a binder resin and a pigment, and this binder resin contains a polyester resin that has a specific structure and specific properties.
    Type: Grant
    Filed: June 11, 2015
    Date of Patent: November 28, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Masatake Tanaka, Yoshihiro Nakagawa, Naoya Isono, Tsutomu Shimano, Shintaro Noji, Yu Yoshida, Takeshi Kaburagi, Shohei Shibahara
  • Patent number: 9785068
    Abstract: The toner has a toner particle that contains a binder resin and a wax, wherein the wax is present in domain form in the interior of the toner particle; the proportion of toner particles for which the position of the wax domains are controlled, is in a prescribed range; using d for a major axis length of the domain having the largest major axis length and using D for a number-average particle diameter of the toner, the d and D satisfy a prescribed relationship; and the ratio between the major axis length and the minor axis length of the domain having the largest major axis length is in a prescribed range.
    Type: Grant
    Filed: August 24, 2016
    Date of Patent: October 10, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Noriyoshi Umeda, Takeshi Kaburagi, Naotaka Ikeda, Hirofumi Kyuushima, Shohei Shibahara, Yoshiaki Wada
  • Publication number: 20170123333
    Abstract: A toner comprising a toner particle containing a binder resin, a colorant and a crystalline resin, wherein the loss elastic modulus G? of the toner at 20° C. is 1.5×108 Pa to 1.0×109 Pa, a shoulder appears at a temperature Tp (° C.) in the range of 30° C. to 45° C. in a temperature-loss elastic modulus curve, and, in Curve 1 obtained by differentiating the temperature-loss elastic modulus curve once by the temperature, the minimum value of the Curve 1 in the range of 60° C. or more is ?0.30 to ?0.15.
    Type: Application
    Filed: October 25, 2016
    Publication date: May 4, 2017
    Inventors: Shiro Kuroki, Kazumi Yoshizaki, Kenichi Nakayama, Yuujirou Nagashima, Takeshi Kaburagi
  • Publication number: 20170075243
    Abstract: The toner has a toner particle that contains a binder resin and a wax, wherein the wax is present in domain form in the interior of the toner particle; the proportion of toner particles for which the position of the wax domains are controlled, is in a prescribed range; using d for a major axis length of the domain having the largest major axis length and using D for a number-average particle diameter of the toner, the d and D satisfy a prescribed relationship; and the ratio between the major axis length and the minor axis length of the domain having the largest major axis length is in a prescribed range.
    Type: Application
    Filed: August 24, 2016
    Publication date: March 16, 2017
    Inventors: Noriyoshi Umeda, Takeshi Kaburagi, Naotaka Ikeda, Hirofumi Kyuushima, Shohei Shibahara, Yoshiaki Wada
  • Publication number: 20150370189
    Abstract: Provided is a toner for which the heat-resistant storability and the low-temperature fixability are able to co-exist at higher levels and for which the temporal stability of the low-temperature fixability is also excellent. The toner has a toner particle that contains a binder resin and a pigment, and this binder resin contains a polyester resin that has a specific structure and specific properties.
    Type: Application
    Filed: June 11, 2015
    Publication date: December 24, 2015
    Inventors: Masatake Tanaka, Yoshihiro Nakagawa, Naoya Isono, Tsutomu Shimano, Shintaro Noji, Yu Yoshida, Takeshi Kaburagi, Shohei Shibahara
  • Patent number: 8865385
    Abstract: The present invention provides a toner that gives satisfactory fixing image quality in both high-speed fixing process and low-speed fixing process and shows excellent image quality for a long time by inhibiting inside contamination even in repeated use. In a toner including toner particles containing a binder resin, a hydrocarbon wax, and a coloring agent, the hydrocarbon wax is prescribed by a relationship in total amounts of components having carbon atoms in specific ranges in thermal desorption and GC/MS analysis when heated at 200° C. for 10 minutes.
    Type: Grant
    Filed: September 6, 2011
    Date of Patent: October 21, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kenichi Nakayama, Shinya Yachi, Takeshi Kaburagi, Nobuhisa Abe, Shiro Kuroki
  • Patent number: 8859177
    Abstract: The present invention provides a toner showing an excellent fixing property even in high-speed image formation and inhibiting contamination of the inside of an apparatus and thereby being capable of stably forming high-quality images not having unevenness of gloss over a long period of time. In the toner including toner particles containing a binder resin, an ester wax, and a coloring agent, the ester wax is prescribed by, in GC/MS analysis of components volatilized by heating the wax at 200° C. for 10 minutes, a relationship in the components having carbon atoms in specific ranges.
    Type: Grant
    Filed: September 6, 2011
    Date of Patent: October 14, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazumi Yoshizaki, Yasushi Katsuta, Kenichi Nakayama, Takeshi Kaburagi, Hideki Kaneko
  • Patent number: 8841056
    Abstract: A toner is provided which has toner particles and an inorganic fine powder; the toner particles being obtained by suspension polymerization using a specific polar resin. The toner is a toner in which; where, in displacement levels found in a micro-compression test in which a force is applied to a toner single particle at a loading rate of 9.8×10?6 N/sec to measure a displacement level (?m) at a point of time where the force has reached a maximum force of 4.90×10?4 N, the displacement level of the toner at a measurement temperature of 25° C. is represented by X(25) and the displacement level of the toner at a measurement temperature of 50° C. by X(50), and the number average particle diameter of the toner is represented by D (?m), the X(25), X(50) and D satisfies the relations: 0.10?X(25)/D?0.35??(1) 30?[X(50)?X(25)]/X(25)×100?150??(2).
    Type: Grant
    Filed: March 28, 2011
    Date of Patent: September 23, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazumi Yoshizaki, Shinya Yachi, Yasushi Katsuta, Kenichi Nakayama, Takeshi Kaburagi
  • Patent number: 8741518
    Abstract: A toner includes toner particles each containing a binder resin, a colorant, and a carboxy-containing styrene-based resin, in which the toner particles are produced in an aqueous medium, each of the toner particles has a styrene-acrylic-based resin component content of 50.0% by mass or more, cyclohexane-insoluble matter A obtained by subjecting the toner to Soxhlet extraction with cyclohexane for 4 hours is 70.0% by mass or more, and cyclohexane-insoluble matter B obtained by subjecting the toner to Soxhlet extraction with cyclohexane for 24 hours is 40.0% by mass or less, and wherein when the z-average molecular weight and the weight-average molecular weight of tetrahydrofuran-soluble matter of the carboxy-containing styrene-based resin determined by gel permeation chromatography measurement are represented by Mz and Mw, respectively, Mz and Mw satisfy the following expressions: 10,000?Mw?30,000, and 1.62?Mz/Mw?5.00.
    Type: Grant
    Filed: April 12, 2011
    Date of Patent: June 3, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hideki Kaneko, Shinya Yachi, Kenichi Nakayama, Takeshi Kaburagi, Shiro Kuroki
  • Patent number: 8518623
    Abstract: A toner includes a toner particle, which contains at least a binding resin, a colorant, and two types of polar resins, i.e., a polar resin H and a polar resin L, and which is obtained with granulation in a water-based medium, wherein solubility parameters, glass transition points, and weight-average molecular weights of the binding resin, the polar resin H, and the polar resin L, as well as amounts of the added resins satisfy respective specific relationships.
    Type: Grant
    Filed: March 30, 2011
    Date of Patent: August 27, 2013
    Assignee: Canon Kabushiki Kasiha
    Inventors: Kenta Kamikura, Shinya Yachi, Kazumi Yoshizaki, Yasushi Katsuta, Takeshi Kaburagi
  • Publication number: 20130171552
    Abstract: The present invention provides a toner showing an excellent fixing property even in high-speed image formation and inhibiting contamination of the inside of an apparatus and thereby being capable of stably forming high-quality images not having unevenness of gloss over a long period of time. In the toner including toner particles containing a binder resin, an ester wax, and a coloring agent, the ester wax is prescribed by, in GC/MS analysis of components volatilized by heating the wax at 200° C. for 10 minutes, a relationship in the components having carbon atoms in specific ranges.
    Type: Application
    Filed: September 6, 2011
    Publication date: July 4, 2013
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Kazumi Yoshizaki, Yasushi Katsuta, Kenichi Nakayama, Takeshi Kaburagi, Hideki Kaneko
  • Publication number: 20130164670
    Abstract: The present invention provides a toner that gives satisfactory fixing image quality in both high-speed fixing process and low-speed fixing process and shows excellent image quality for a long time by inhibiting inside contamination even in repeated use. In a toner including toner particles containing a binder resin, a hydrocarbon wax, and a coloring agent, the hydrocarbon wax is prescribed by a relationship in total amounts of components having carbon atoms in specific ranges in thermal desorption and GC/MS analysis when heated at 200° C. for 10 minutes.
    Type: Application
    Filed: September 6, 2011
    Publication date: June 27, 2013
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Kenichi Nakayama, Shinya Yachi, Takeshi Kaburagi, Nobuhisa Abe, Shiro Kuroki
  • Publication number: 20120328979
    Abstract: A toner is provided which has toner particles and an inorganic fine powder; the toner particles being obtained by suspension polymerization using a specific polar resin. The toner is a toner in which; where, in displacement levels found in a micro-compression test in which a force is applied to a toner single particle at a loading rate of 9.8×10?6 N/sec to measure a displacement level (?m) at a point of time where the force has reached a maximum force of 4.90×10?4 N, the displacement level of the toner at a measurement temperature of 25° C. is represented by X(25) and the displacement level of the toner at a measurement temperature of 50° C. by X(50), and the number average particle diameter of the toner is represented by D (?m), the X(25), X(50) and D satisfies the relations: 0.10?X(25)/D?0.35??(1) 30?[X(50)?X(25)]/X(25)×100?150??(2).
    Type: Application
    Filed: March 28, 2011
    Publication date: December 27, 2012
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Kazumi Yoshizaki, Shinya Yachi, Yasushi Katsuta, Kenichi Nakayama, Takeshi Kaburagi
  • Publication number: 20110256477
    Abstract: A toner includes toner particles each containing a binder resin, a colorant, and a carboxy-containing styrene-based resin, in which the toner particles are produced in an aqueous medium, each of the toner particles has a styrene-acrylic-based resin component content of 50.0% by mass or more, cyclohexane-insoluble matter A obtained by subjecting the toner to Soxhlet extraction with cyclohexane for 4 hours is 70.0% by mass or more, and cyclohexane-insoluble matter B obtained by subjecting the toner to Soxhlet extraction with cyclohexane for 24 hours is 40.0% by mass or less, and wherein when the z-average molecular weight and the weight-average molecular weight of tetrahydrofuran-soluble matter of the carboxy-containing styrene-based resin determined by gel permeation chromatography measurement are represented by Mz and Mw, respectively, Mz and Mw satisfy the following expressions: 10,000?Mw?30,000, and 1.62?Mz/Mw?5.00.
    Type: Application
    Filed: April 12, 2011
    Publication date: October 20, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Hideki Kaneko, Shinya Yachi, Kenichi Nakayama, Takeshi Kaburagi, Shiro Kuroki
  • Publication number: 20110244386
    Abstract: A toner includes a toner particle, which contains at least a binding resin, a colorant, and two types of polar resins, i.e., a polar resin H and a polar resin L, and which is obtained with granulation in a water-based medium, wherein solubility parameters, glass transition points, and weight-average molecular weights of the binding resin, the polar resin H, and the polar resin L, as well as amounts of the added resins satisfy respective specific relationships.
    Type: Application
    Filed: March 30, 2011
    Publication date: October 6, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Kenta Kamikura, Shinya Yachi, Kazumi Yoshizaki, Yasushi Katsuta, Takeshi Kaburagi
  • Patent number: 7560212
    Abstract: The present invention provides a magnetic toner which is hardly influenced by an environment, and with which an image with high quality and excellent resolution can be stably even under low humidity. In the magnetic toner of present invention: I) a ratio of an iron element content to a carbon element content present on the toner particle surface is less than 0.0010; II) 50 number % or more of toner particles satisfy a relationship of D/C?0.02 (C: projected area diameter of toner particles, D: minimum value for a distance between a magnetic iron oxide fine particle and the toner particle surface); and III) 40-95 number % of toner particles satisfy a structure where 70 number % or more of the magnetic iron oxide fine particles in the respective toner particles are present up to a depth of 0.2 time as far as C from the toner particle surface.
    Type: Grant
    Filed: March 18, 2008
    Date of Patent: July 14, 2009
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tatsuhiko Chiba, Michihisa Magome, Eriko Yanase, Takeshi Kaburagi
  • Publication number: 20080171277
    Abstract: The present invention provides a magnetic toner which is hardly influenced by an environment, and with which an image with high quality and excellent resolution can be stably even under low humidity. In the magnetic toner of present invention: I) a ratio of an iron element content to a carbon element content present on the toner particle surface is less than 0.0010; II) 50 number % or more of toner particles satisfy a relationship of D/C?0.02 (C: projected area diameter of toner particles, D: minimum value for a distance between a magnetic iron oxide fine particle and the toner particle surface); and III) 40-95 number % of toner particles satisfy a structure where 70 number % or more of the magnetic iron oxide fine particles in the respective toner particles are present up to a depth of 0.2 time as far as C from the toner particle surface.
    Type: Application
    Filed: March 18, 2008
    Publication date: July 17, 2008
    Applicant: Canon Kabushiki Kaisha
    Inventors: Tatsuhiko Chiba, Michihisa Magome, Eriko Yanase, Takeshi Kaburagi
  • Patent number: 7387860
    Abstract: A toner includes toner particles containing at least a binder resin and a colorant, and inorganic fine particles. The shape factor SF-1 of the toner particles is in a specific range. The toner has a storage elastic modulus at 140° C., G? (140° C.), in a specific range the toner comes to have a viscosity of 1.0×103 Pa·s according to a flow tester heating method at a temperature of from 115° C. or more to less than 130° C.
    Type: Grant
    Filed: June 5, 2007
    Date of Patent: June 17, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yuji Moriki, Shinya Yachi, Yushi Mikuriya, Keiji Komoto, Kenichi Nakayama, Takeshi Kaburagi, Emi Tosaka