Patents by Inventor Masami Fujimoto

Masami Fujimoto 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: 10747135
    Abstract: A toner including a toner particle; and an external additive, wherein the external additive contains strontium titanate particle, and when in a projected image of the strontium titanate particle photographed using a scanning electron microscope, a standard deviation of a distance from a center of the projected image to an outline of the projected image is Ds, and a circle-equivalent diameter of the projected image is Da, a value CV calculated by Equation (1) is 0.07 or less, CV=Ds/(Da/2)??(1).
    Type: Grant
    Filed: February 26, 2019
    Date of Patent: August 18, 2020
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yojiro Hotta, Koji Nishikawa, Kazuo Terauchi, Takaaki Furui, Ryo Nagata, Keisuke Tanaka, Masami Fujimoto
  • Patent number: 10488777
    Abstract: A toner contains toner particles, titanate fine particles having a Group II element, and hydrotalcite compound fine particles as an external additive and satisfying 10?Lt?80 and 100?Lh?Weight average particle diameter (D4) of toner particles×0.50, when the number average particle diameter (D1) of primary particles of the titanate fine particles is defined as Lt (nm) and the number average particle diameter (D1) of primary particles of the hydrotalcite compound fine particles is defined as Lh (nm).
    Type: Grant
    Filed: August 23, 2018
    Date of Patent: November 26, 2019
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazuo Terauchi, Yojiro Hotta, Koji Nishikawa, Masami Fujimoto, Takaaki Furui, Ryo Nagata, Keisuke Tanaka
  • Publication number: 20190271928
    Abstract: A toner including a toner particle; and an external additive, wherein the external additive contains strontium titanate particle, and when in a projected image of the strontium titanate particle photographed using a scanning electron microscope, a standard deviation of a distance from a center of the projected image to an outline of the projected image is Ds, and a circle-equivalent diameter of the projected image is Da, a value CV calculated by Equation (1) is 0.07 or less, CV=Ds/(Da/2)??(1).
    Type: Application
    Filed: February 26, 2019
    Publication date: September 5, 2019
    Inventors: Yojiro Hotta, Koji Nishikawa, Kazuo Terauchi, Takaaki Furui, Ryo Nagata, Keisuke Tanaka, Masami Fujimoto
  • Patent number: 10303075
    Abstract: A toner including a toner particle and an external additive, wherein the external additive contains an inorganic fine particle A and a silica fine particle; in a surface of the toner observed using a scanning electron microscope, a number-average particle diameter of primary particle of the silica fine particle is from 5 nm to 50 nm, a number-average particle diameter of primary particle of the inorganic fine particle A is at least 10 nm and less than 60 nm, a coverage ratio X1 of the toner surface covered by the silica fine particle is from 60 area % to 95 area %, the inorganic fine particle A is a fine particle of a titanate having a Group 2 element, and a coverage ratio X2 of the toner surface covered by the inorganic fine particle A is from 5 area % to 40 area %.
    Type: Grant
    Filed: February 23, 2018
    Date of Patent: May 28, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Keisuke Tanaka, Yojiro Hotta, Kazuo Terauchi, Koji Nishikawa, Takaaki Furui, Ryo Nagata, Kazuyuki Sato, Yu Yoshida, Yusuke Kosaki, Masami Fujimoto
  • Patent number: 10295920
    Abstract: Provided is toner that contains a toner particle, and an external additive containing a strontium titanate particle, wherein the toner has an average circularity of at least 0.935 and not more than 0.995, the strontium titanate particle has a number-average primary particle diameter of at least 10 nm and not more than 60 nm, the strontium titanate particle has a peak in the range of 39.700°±0.150° and a peak in the range of 46.200°±0.150° in a CuK? x-ray diffraction spectrum obtained in the 2? range of at least 10° and not more than 90° where ? is the Bragg angle, and the ratio of the area Sb of the peak at 46.200°±0.150° to the area Sa of the peak at 39.700°±0.150° is at least 1.80 and not more than 2.30.
    Type: Grant
    Filed: February 21, 2018
    Date of Patent: May 21, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Koji Nishikawa, Yojiro Hotta, Kazuo Terauchi, Takaaki Furui, Ryo Nagata, Keisuke Tanaka, Kazuyuki Sato, Yu Yoshida, Yusuke Kosaki, Masami Fujimoto
  • Patent number: 10228630
    Abstract: A toner comprising an external additive A, and a toner particle containing a binder resin and a colorant, wherein the external additive A: i) is an external additive that has a charge control agent on the surface thereof; ii) has a wall friction angle ? calculated from the following formula (1) of not more than 25.0° ?=?/5.0??formula (1); iii) has a number-average particle diameter (D1) of primary particles of at least 70 nm and not more than 500 nm; and iv) has a solidity as given by the following formula (2) of at least 0.40 and not more than 0.90 solidity=area of external additive A/area of region encompassed by envelope for external additive A?? formula (2).
    Type: Grant
    Filed: September 7, 2017
    Date of Patent: March 12, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Takuya Mizuguchi, Kazuo Terauchi, Yojiro Hotta, Takeshi Naka, Motohide Shiozawa, Masami Fujimoto
  • Publication number: 20190064686
    Abstract: A toner contains toner particles, titanate fine particles having a Group II element, and hydrotalcite compound fine particles as an external additive and satisfying 10?Lt?80 and 100?Lh?Weight average particle diameter (D4) of toner particles×0.50, when the number average particle diameter (D1) of primary particles of the titanate fine particles is defined as Lt (nm) and the number average particle diameter (D1) of primary particles of the hydrotalcite compound fine particles is defined as Lh (nm).
    Type: Application
    Filed: August 23, 2018
    Publication date: February 28, 2019
    Inventors: Kazuo Terauchi, Yojiro Hotta, Koji Nishikawa, Masami Fujimoto, Takaaki Furui, Ryo Nagata, Keisuke Tanaka
  • 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
  • Publication number: 20180246430
    Abstract: A toner including a toner particle and an external additive, wherein the external additive contains an inorganic fine particle A and a silica fine particle; in a surface of the toner observed using a scanning electron microscope, a number-average particle diameter of primary particle of the silica fine particle is from 5 nm to 50 nm, a number-average particle diameter of primary particle of the inorganic fine particle A is at least 10 nm and less than 60 nm, a coverage ratio X1 of the toner surface covered by the silica fine particle is from 60 area % to 95 area %, the inorganic fine particle A is a fine particle of a titanate having a Group 2 element, and a coverage ratio X2 of the toner surface covered by the inorganic fine particle A is from 5 area % to 40 area %.
    Type: Application
    Filed: February 23, 2018
    Publication date: August 30, 2018
    Inventors: Keisuke Tanaka, Yojiro Hotta, Kazuo Terauchi, Koji Nishikawa, Takaaki Furui, Ryo Nagata, Kazuyuki Sato, Yu Yoshida, Yusuke Kosaki, Masami Fujimoto
  • Publication number: 20180246432
    Abstract: Provided is toner that contains a toner particle, and an external additive containing a strontium titanate particle, wherein the toner has an average circularity of at least 0.935 and not more than 0.995, the strontium titanate particle has a number-average primary particle diameter of at least 10 nm and not more than 60 nm, the strontium titanate particle has a peak in the range of 39.700°±0.150° and a peak in the range of 46.200°±0.150° in a CuK? x-ray diffraction spectrum obtained in the 2? range of at least 10° and not more than 90° where ? is the Bragg angle, and the ratio of the area Sb of the peak at 46.200°±0.150° to the area Sa of the peak at 39.700°±0.150° is at least 1.80 and not more than 2.30.
    Type: Application
    Filed: February 21, 2018
    Publication date: August 30, 2018
    Inventors: Koji Nishikawa, Yojiro Hotta, Kazuo Terauchi, Takaaki Furui, Ryo Nagata, Keisuke Tanaka, Kazuyuki Sato, Yu Yoshida, Yusuke Kosaki, Masami Fujimoto
  • Publication number: 20180074425
    Abstract: A toner comprising an external additive A, and a toner particle containing a binder resin and a colorant, wherein the external additive A: i) is an external additive that has a charge control agent on the surface thereof; ii) has a wall friction angle ? calculated from the following formula (1) of not more than 25.0° ?=?/5.0??formula (1); iii) has a number-average particle diameter (D1) of primary particles of at least 70 nm and not more than 500 nm; and iv) has a solidity as given by the following formula (2) of at least 0.40 and not more than 0.90 solidity=area of external additive A/area of region encompassed by envelope for external additive A?? formula (2).
    Type: Application
    Filed: September 7, 2017
    Publication date: March 15, 2018
    Inventors: Takuya Mizuguchi, Kazuo Terauchi, Yojiro Hotta, Takeshi Naka, Motohide Shiozawa, Masami Fujimoto
  • Patent number: 9897932
    Abstract: A toner comprising: a toner particle containing a toner base particle containing a binder resin and a colorant, and a resin particle fixed to a surface of the toner base particle; and an inorganic fine particle A, wherein the surface of the toner particle has protruded portions originating in the resin particle, an average length (D) of long sides of the protruded portions is 50 nm to 300 nm, an average Height (H) of the protruded portions is 25 nm to 250 nm, the average long-side length and the average height of the protruded portions satisfies a specific relationship, and an average value of a compactness of the inorganic fine particle A is 0.40 to 0.80, and the attachment rate of the inorganic fine particles A is 0.1% to 5.0% by area.
    Type: Grant
    Filed: January 31, 2017
    Date of Patent: February 20, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yojiro Hotta, Kazuo Terauchi, Tsuneyoshi Tominaga, Akane Masumoto, Takuya Mizuguchi, Motohide Shiozawa, Takeshi Naka, Masami Fujimoto, Shingo Ito, Kousuke Yamamoto, Yasukazu Ikami
  • 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
  • Patent number: 9778583
    Abstract: A toner having compatibility between transfer properties and cleaning properties is provided. A toner wherein a fine particle A containing a primary particle having a number average particle diameter (D1) of 80 nm or more and 400 nm or less is present on the surface of a toner particle at a coverage ratio of 5 to 40%, a fixing rate of 30 to 90% by mass, and a variation coefficient of 0.1 to 0.5 in a region of 0.5 ??m2.
    Type: Grant
    Filed: August 3, 2015
    Date of Patent: October 3, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kazuo Terauchi, Yojiro Hotta, Takeshi Naka, Motohide Shiozawa, Shohei Tsuda, Masami Fujimoto
  • Patent number: 9772570
    Abstract: Provided is a toner having good endurance stability and good low-temperature fixability in high-speed printing, and having good resistance to the adhesion of printed paper. The toner is a magnetic toner having, on the surface of toner particle containing a binder resin and an ester compound as a releasing agent, inorganic fine particle “a” and organic-inorganic composite fine particle having a volumetric specific heat of from 2,900 kJ/(m3·° C.) to 4,200 kJ/(m3·° C.), in which a coverage A of the surface of the toner particle with the inorganic fine particle “a” is 45.0% or more and 70.0% or less.
    Type: Grant
    Filed: July 29, 2015
    Date of Patent: September 26, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Shohei Tsuda, Yojiro Hotta, Koji Nishikawa, Masami Fujimoto, Katsuhisa Yamazaki
  • Publication number: 20170227864
    Abstract: A toner comprising: a toner particle containing a toner base particle containing a binder resin and a colorant, and a resin particle fixed to a surface of the toner base particle; and an inorganic fine particle A, wherein the surface of the toner particle has protruded portions originating in the resin particle, an average length (D) of long sides of the protruded portions is 50 nm to 300 nm, an average Height (H) of the protruded portions is 25 nm to 250 nm, the average long-side length and the average height of the protruded portions satisfies a specific relationship, and an average value of a compactness of the inorganic fine particle A is 0.40 to 0.80, and the attachment rate of the inorganic fine particles A is 0.1% to 5.0% by area.
    Type: Application
    Filed: January 31, 2017
    Publication date: August 10, 2017
    Inventors: Yojiro Hotta, Kazuo Terauchi, Tsuneyoshi Tominaga, Akane Masumoto, Takuya Mizuguchi, Motohide Shiozawa, Takeshi Naka, Masami Fujimoto, Shingo Ito, Kousuke Yamamoto, Yasukazu Ikami
  • Patent number: 9500970
    Abstract: Provided is a toner that has excellent low-temperature fixability and is capable of obtaining an image having a stable image density, in which the occurrence of image defects is suppressed. The toner includes toner base particles, each of which contains a binder resin and a magnetic material, and organic-inorganic composite fine particles on each of the toner base particles. Each of the organic-inorganic composite fine particles comprises a vinyl resin particle, and inorganic fine particles which are embedded in the vinyl resin particle, and at least a part of which are exposed. The volumetric specific heat of the organic-inorganic composite fine particles and the volumetric specific heat of the toner base particles satisfy a predetermined provision.
    Type: Grant
    Filed: July 30, 2014
    Date of Patent: November 22, 2016
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shotaro Nomura, Masami Fujimoto, Katsuhisa Yamazaki, Kouji Nishikawa, Daisuke Yoshiba, Hiroki Akiyama
  • Publication number: 20160179024
    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: Application
    Filed: July 25, 2014
    Publication date: June 23, 2016
    Inventors: Kouji Nishikawa, Katsuhisa Yamazaki, Daisuke Yoshiba, Shotaro Nomura, Hiroki Akiyama, Masami Fujimoto
  • Publication number: 20160161874
    Abstract: A magnetic toner comprising a toner particle containing a styrene resin as a binder resin and a magnetic substance, and a first inorganic fine particle on surface of the toner particle and an organic-inorganic composite fine particle on the surface of the toner particle, wherein the first inorganic fine particle i) contains at least one inorganic oxide fine particle selected from the group consisting of silica fine particle, titanium oxide fine particle and alumina fine particle, with the proviso that the inorganic oxide fine particle contains silica fine particle in an amount of 85 mass % or more based on the total mass of the inorganic oxide fine particle, and ii) has a number-average particle diameter (D1) of 5 nm or more and 25 nm or less, the coverage ratio A of the toner-particle surface with the first inorganic fine particle is 45.0% or more and 70.0% or less.
    Type: Application
    Filed: July 30, 2014
    Publication date: June 9, 2016
    Inventors: Katsuhisa Yamazaki, Koji Nishikawa, Daisuke Yoshiba, Shotaro Nomura, Hiroki Akiyama, Masami Fujimoto
  • Patent number: 9341970
    Abstract: The toner includes a resin component containing a crystalline polyester resin and a polyester-type resin that has a long-chain monomer bonded by condensation at a terminal, the toner having, in a total heat flow measured by a temperature-modulated differential scanning calorimeter, an endothermic peak resulting from the crystalline polyester resin in a specific temperature range, and the percentage of the endothermic quantity of the endothermic peak in a reversing heat flow with respect to the endothermic quantity of the endothermic peak in the total heat flow being at least 20.0%.
    Type: Grant
    Filed: July 29, 2014
    Date of Patent: May 17, 2016
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Daisuke Yoshiba, Katsuhisa Yamazaki, Koji Nishikawa, Shotaro Nomura, Hiroki Akiyama, Masami Fujimoto