Patents by Inventor Kazuo Terauchi

Kazuo Terauchi 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
  • 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: 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
  • 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: 9715188
    Abstract: The toner comprising a toner particle containing a binder resin and a colorant, an iron oxide particle and an organic-inorganic composite fine particle, wherein the organic-inorganic composite fine particle comprises a vinyl resin particle, and inorganic fine particles which are embedded in the vinyl resin particle, and at least a part of which is exposed at surface of the organic-inorganic composite fine particle; the organic-inorganic composite fine particle has convexes derived from the inorganic fine particles, and wherein: a coverage ratio of the surface of the organic-inorganic composite fine particle with the inorganic fine particle is 20-70%; and the content of the iron oxide particle present on a surface of the toner particle is 0.1-5.0 mass % based on the mass of the toner particle.
    Type: Grant
    Filed: July 30, 2014
    Date of Patent: July 25, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kazuo Terauchi, Koji Nishikawa, Shohei Tsuda, Yojiro Hotta, Katsuhisa Yamazaki, Takayuki Itakura, Takeshi Naka, Motohide Shiozawa
  • Patent number: 9588450
    Abstract: Provided is a magnetic toner in which enhancement of initial transfer efficiency and transfer efficiency that is stable during a long-term use are achieved by simultaneously suppressing the friction force between the toner and a drum and the cohesion between toners, and further the degradation in chargeability and fluidity caused by the deterioration of the toner. The magnetic toner includes: a magnetic toner particle; a first external additive; and a second external additive. The first external additive includes an organic-inorganic composite fine particle, a plurality of convexes derived from an inorganic fine particle being present on a surface of the organic-inorganic composite fine particle, and has a number-average particle diameter of 50 nm or more and 500 nm or less. The second external additive includes a silica fine particle and has a number-average particle diameter of 5 nm or more and 30 nm or less. A shear load calculated from a rotation torque is 0.50 kPa or more and 2.
    Type: Grant
    Filed: July 30, 2014
    Date of Patent: March 7, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Shohei Tsuda, Koji Nishikawa, Katsuhisa Yamazaki, Yojiro Hotta, Kazuo Terauchi, Motohide Shiozawa, Takeshi Naka, Takuya Mizuguchi, Takayuki Itakura
  • Patent number: 9575425
    Abstract: A toner is provided including large particle-diameter external additives with sweep to the concaves of a toner particle suppressed, so that the large particle-diameter external additives function as spacer particles for a long period. The toner includes toner particles which contain a binder resin and magnetic material, and organic-inorganic composite fine particles having a structure including inorganic fine particles embedded in a vinyl resin particle. The presence state of the magnetic material on the toner particle surface satisfies specific conditions and the presence state of the organic-inorganic composite fine particles on the toner surface satisfies specific conditions.
    Type: Grant
    Filed: July 29, 2014
    Date of Patent: February 21, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Takeshi Naka, Kazuo Terauchi, Motohide Shiozawa, Yojiro Hotta, Shohei Tsuda, Katsuhisa Yamazaki, Koji Nishikawa, Takayuki Itakura
  • Publication number: 20160091809
    Abstract: Provided is a magnetic toner in which enhancement of initial transfer efficiency and transfer efficiency that is stable during a long-term use are achieved by simultaneously suppressing the friction force between the toner and a drum and the cohesion between toners, and further the degradation in chargeability and fluidity caused by the deterioration of the toner. The magnetic toner includes: a magnetic toner particle; a first external additive; and a second external additive. The first external additive includes an organic-inorganic composite fine particle, a plurality of convexes derived from an inorganic fine particle being present on a surface of the organic-inorganic composite fine particle, and has a number-average particle diameter of 50 nm or more and 500 nm or less. The second external additive includes a silica fine particle and has a number-average particle diameter of 5 nm or more and 30 nm or less. A shear load calculated from a rotation torque is 0.50 kPa or more and 2.
    Type: Application
    Filed: July 30, 2014
    Publication date: March 31, 2016
    Inventors: Shohei Tsuda, Koji Nishikawa, Katsuhisa Yamazaki, Yojiro Hotta, Kazuo Terauchi, Motohide Shiozawa, Takeshi Naka, Takuya Mizuguchi, Takayuki Itakura
  • Publication number: 20160070192
    Abstract: The toner comprising a toner particle containing a binder resin and a colorant, an iron oxide particle and an organic-inorganic composite fine particle, wherein the organic-inorganic composite fine particle comprises a vinyl resin particle, and inorganic fine particles which are embedded in the vinyl resin particle, and at least a part of which is exposed at surface of the organic-inorganic composite fine particle; the organic-inorganic composite fine particle has convexes derived from the inorganic fine particles, and wherein: a coverage ratio of the surface of the organic-inorganic composite fine particle with the inorganic fine particle is 20-70%; and the content of the iron oxide particle present on a surface of the toner particle is 0.1-5.0 mass % based on the mass of the toner particle.
    Type: Application
    Filed: July 30, 2014
    Publication date: March 10, 2016
    Inventors: Kazuo Terauchi, Koji Nishikawa, Shohei Tsuda, Yojiro Hotta, Katsuhisa Yamazaki, Takayuki Itakura, Takeshi Naka, Motohide Shiozawa
  • Publication number: 20160041482
    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: Application
    Filed: August 3, 2015
    Publication date: February 11, 2016
    Inventors: Kazuo Terauchi, Yojiro Hotta, Takeshi Naka, Motohide Shiozawa, Shohei Tsuda, Masami Fujimoto
  • Patent number: 9141012
    Abstract: The toner includes toner particles containing a polyester resin A, a polyester resin B and a colorant, the polyester resin A has a polyester portion including a segment capable of forming a crystal structure and a crystal nucleating agent segment, which is bonded to an end of the polyester portion, and the polyester resin B is a resin which is free of any segments capable of forming a crystal structure, the polyester resin B has a weight average molecular weight Mwb by GPC of a THF soluble matter of 3000 or more and 100000 or less, and an SP value Sa ((cal/cm3)1/2) of the polyester portion of the polyester resin A and an SP value Sb ((cal/cm3)1/2) of the polyester resin B satisfy the following relationships: 9.00?Sa?10.50 ?0.40?Sb?Sa?0.80.
    Type: Grant
    Filed: December 12, 2013
    Date of Patent: September 22, 2015
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Shuhei Moribe, Kosuke Fukudome, Satoshi Mita, Kazuo Terauchi, Yojiro Hotta, Tetsuya Ida