Patents by Inventor Hitoshi Kanda

Hitoshi Kanda 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: 6627374
    Abstract: A process for producing toner particles, comprising polymerizing in an aqueous dispersion medium a polymerizable monomer composition containing at least a polymerizable monomer and a colorant, to form colored polymer particles, followed by washing and then dehydration to obtain toner particles, and feeding the toner particles into an inside-evacuatable and heatable container to make vacuum heat treatment while introducing into the container an injection medium having a temperature lower than glass transition temperature Tg of the toner particles and selected from the group consisting of i) saturated steam, ii) superheated steam and iii) high-humidity air having an enthalpy of 2,500 kJ/kg (dry air) or higher. Also disclosed is a system which carries out the above process.
    Type: Grant
    Filed: May 29, 2001
    Date of Patent: September 30, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hidekazu Fumita, Hitoshi Kanda, Hiroshi Koyama, Minoru Omura
  • Patent number: 6495303
    Abstract: A process for producing polymerized toner comprises polymerizing a composition containing a polymerizable monomer and a colorant in a medium to form colored resin particles, separating the particles from the medium by filtration, and drying the separated particles. The separation of the particles from the medium is effected by a decanter-type centrifugal separator equipped with an outer rotary cylinder which contains a screw conveyor freely rotating relative to the cylinder.
    Type: Grant
    Filed: October 31, 2000
    Date of Patent: December 17, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hitoshi Kanda, Takeshi Naka, Hiroshi Koyama, Yoshinori Tsuji
  • Publication number: 20020031714
    Abstract: A process for producing toner particles, comprising polymerizing in an aqueous dispersion medium a polymerizable monomer composition containing at least a polymerizable monomer and a colorant, to form colored polymer particles, followed by washing and then dehydration to obtain toner particles, and feeding the toner particles into an inside-evacuatable and heatable container to make vacuum heat treatment while introducing into the container an injection medium having a temperature lower than glass transition temperature Tg of the toner particles and selected from the group consisting of i) saturated steam, ii) superheated steam and iii) high-humidity air having an enthalpy of 2,500 kJ/kg (dry air) or higher. Also disclosed is a system which carries out the above process.
    Type: Application
    Filed: May 29, 2001
    Publication date: March 14, 2002
    Inventors: Hidekazu Fumita, Hitoshi Kanda, Hiroshi Koyama, Minoru Omura
  • Patent number: 6309788
    Abstract: A process for producing a toner. The process has the steps of dispersing a fine-particle colorant in a liquid monomer mixture containing at least a liquid polymerizable monomer, dispersing the resulting colorant-dispersed liquid monomer mixture in an aqueous dispersion medium to form particles of a polymerizable monomer composition, and polymerizing polymerizable monomers present in the particles in the aqueous dispersion medium to form toner particles. In the dispersion step, a media particle agitation type wet-dispersion machine is used as a dispersion means. The dispersion machine has a cylindrical vessel having a first wall surface having a liquid-feed opening and a second wall surface having a liquid-discharge opening.
    Type: Grant
    Filed: November 4, 1999
    Date of Patent: October 30, 2001
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yoshinori Tsuji, Atsushi Kubo, Minoru Ohmura, Hitoshi Kanda, Takeshi Tsujino
  • Patent number: 6207339
    Abstract: A process for producing a toner has the steps of, polymerizing a polymerizable monomer composition containing at least a polymerizable monomer and a colorant, in an aqueous dispersion medium to form colored polymer particles, and thereafter washing the colored polymer particles, followed by dewatering to prepare wet colored polymer particles, subjecting the resultant wet colored polymer particles to substantial removal of the water held by the wet colored polymer particles, by means of a dryer making use of hot air to obtain toner particles, and drying the toner particles under reduced pressure by means of a vacuum dryer so that polymerizable monomers remaining in the toner particles come to be in a residue of 200 ppm or less.
    Type: Grant
    Filed: August 19, 1999
    Date of Patent: March 27, 2001
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masayoshi Kato, Hitoshi Kanda, Tatsuya Nakamura
  • Patent number: 5931306
    Abstract: A gas current classifier has a material feed nozzle, a Coanda block, a classifying wedge and a classifying wedge block having the classifying wedge. The Coanda block and the classifying wedge define a classification zone, and the classifying wedge block is set up in the manner that its location is changeable so that the form of the classification zone can be changed.
    Type: Grant
    Filed: November 10, 1997
    Date of Patent: August 3, 1999
    Assignee: Canon Kabushiki Kaisha
    Inventors: Satoshi Mitsumura, Hitoshi Kanda, Masayoshi Kato, Yoko Goka, Yoshinori Tsuji
  • Patent number: 5916726
    Abstract: A process for producing a toner for developing electrostatic images is disclosed. A polymerizable monomer composition is first prepared and dispersed in an aqueous medium by the action of high shear force to produce particles. The polymerizable monomer is then polymerized in a container having a jacket. The liquid temperature inside the container is controlled by feeding a high-pressure vapor into the jacket while adjusting the degree of vacuum inside the jacket. The production process can achieve a superior temperature response, can keep the reaction system at a constant temperature with ease and can realize shortened production time and reduced production cost.
    Type: Grant
    Filed: February 6, 1998
    Date of Patent: June 29, 1999
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hitoshi Kanda, Kuniaki Kamiichi
  • Patent number: 5856056
    Abstract: In the present process for producing a toner, previous to the melt-kneading process, the binder resin particles and colorant particles are mixed and treated to application of shear, compression and impact forces to fasten, or fix, the colorant particles to the binder resin particles.
    Type: Grant
    Filed: December 3, 1992
    Date of Patent: January 5, 1999
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazuhiko Omata, Yasuhide Goseki, Hitoshi Kanda, Satoshi Mitsumura
  • Patent number: 5839670
    Abstract: A pneumatic pulverizer comprises an accelerating tube for carrying and accelerating powder to be pulverized with high-pressure gas and a pulverizing chamber for pulverizing the powder to be pulverized. The back end of the accelerating tube is provided with a pulverization powder feed port for feeding powder to be pulverized to the accelerating tube, the pulverizing chamber has an impact member having an impact surface opposed to the opening plane of the outlet of the accelerating tube, the and a side wall against which the powder to be pulverized that has been pulverized by the impact member collides to further pulverize.
    Type: Grant
    Filed: May 1, 1996
    Date of Patent: November 24, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazuhiko Omata, Hitoshi Kanda, Momosuke Takaichi, Satoshi Mitsumura, Kazuyuki Miyano
  • Patent number: 5712075
    Abstract: A gas current toner classifier has a material feed nozzle, a Coanda block, a classifying wedge and a classifying wedge block having the classifying wedge.The Coanda block and the classifying wedge define a classification zone, and the classifying wedge block is set up in the manner that its location is changeable so that the form of the classification zone can be changed. A method of producing toner using said classifier is also described.
    Type: Grant
    Filed: January 23, 1995
    Date of Patent: January 27, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Satoshi Mitsumura, Hitoshi Kanda, Masayoshi Kato, Yoko Goka, Yoshinori Tsuji
  • Patent number: 5577670
    Abstract: A pneumatic pulverizer comprises an accelerating tube for carrying and accelerating powder to be pulverized with high-pressure gas and a pulverizing chamber for pulverizing the powder to be pulverized. The back end of the accelerating tube is provided with a pulverization powder feed port for feeding powder to be pulverized to the accelerating tube, the pulverizing chamber has an impact member having an impact surface opposed to the opening plane of the outlet of the accelerating tube, and a side wall against which the powder to be pulverized that has been pulverized by the impact member collides to further pulverize. The closest distance from the side wall to a margin of the impact member is shorter than the closest distance from the front wall of the pulverizing chamber opposed to the impact surface to the margin of the impact member to prevent pulverized powder from fusing, coagulating, and getting coarser, and prevent localized abrasion of an impact surface the impact member and the accelerating tube.
    Type: Grant
    Filed: January 18, 1995
    Date of Patent: November 26, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazuhiko Omata, Hitoshi Kanda, Momosuke Takaichi, Satoshi Mitsumura, Kazuyuki Miyano
  • Patent number: 5447275
    Abstract: A gas stream classifier includes: a gas stream classifying means for classifying feed powder into at least a coarse powder fraction and a fine powder fraction by an inertia force acting on particles and a centrifugal force acting on a curved gas stream due to Coanda effect in a classifying chamber, and a feed supply pipe opening into the classifying chamber for supplying the feed powder into the classifying chamber. The efficiency of the classifier is improved by providing the feed supply pipe with a mixing zone for mixing an upper stream and a lower stream of the feed powder and an accompanying gas stream, respectively flowing through within the feed supply pipe. The classifier is particularly suitably used for producing a toner for developing electrostatic images having a sharp particle size distribution from toner particles having a weight-average particle size of at most 10 .mu.m, especially at most 8 .mu.m.
    Type: Grant
    Filed: January 27, 1994
    Date of Patent: September 5, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yoko Goka, Hitoshi Kanda, Satoshi Mitsumura, Kazuyuki Miyano
  • Patent number: 5435496
    Abstract: A pneumatic pulverizer comprises an acceleration pipe for transporting powders under acceleration by a high pressure gas, a pulverization chamber, a collision member for pulverizing the powders ejected from the acceleration pipe by a force of collision, the collision member being provided against the outlet of the acceleration pipe, a raw material powder supply inlet provided on the acceleration pipe, and a secondary air inlet provided between the raw material powder supply inlet and the outlet of the acceleration pipe.
    Type: Grant
    Filed: January 7, 1994
    Date of Patent: July 25, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hitoshi Kanda, Masayoshi Kato, Satoshi Mitsumura, Yusuke Yamada, Yasuhide Goseki
  • Patent number: 5358183
    Abstract: A pneumatic pulverizer includes an accelerating tube for conveying and accelerating a material to be pulverlized by a high-pressure gas and a pulverizing chamber for finely pulverizing the material to be pulverized. The pulverizing chamber is provided with a colliding member having a colliding surface provided in opposed relation to an outlet of the accelerating tube. The colliding surface of the colliding member has a protruding central portion, and an outer peripheral colliding surface provided around the protruding central portion for secondarily pulverizing the material primarily pulverized by the protruding central portion. The pulverizing chamber has a side wall for performing tertiary pulverization on the material secondarily pulverized by the outer peripheral colliding surface.
    Type: Grant
    Filed: January 19, 1994
    Date of Patent: October 25, 1994
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hitoshi Kanda, Satoshi Mitsumura, Kazuhiko Omata
  • Patent number: 5316222
    Abstract: A pneumatic pulverizer comprises an acceleration pipe for transporting powders under acceleration by a high pressure gas, a pulverization chamber, a collision member for pulverizing the powders ejected from the acceleration pipe by a force of collision, the collision member being provided against the outlet of the acceleration pipe, a raw material powder supply inlet provided on the acceleration pipe, and a secondary air inlet provided between the raw material powder supply inlet and the outlet of the acceleration pipe.
    Type: Grant
    Filed: November 30, 1992
    Date of Patent: May 31, 1994
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hitoshi Kanda, Masayoshi Kato, Satoshi Mitsumura, Yusuke Yamada, Yasuhide Goseki
  • Patent number: 5215854
    Abstract: A microcapsule toner is produced through the steps of: passing resinous base particles (A1) comprising at least a binder resin and modifier particles (B) having a particle size ratio of 0.2 or less with respect to the base particles (A1) through an impact zone having a minimum clearance of 0.5-5 mm between a rotating member and a fixed member or between at least two rotating members at an ambient temperature of 10.degree.-90.degree. C. thereby to fix the modifier particles (B) onto the surfaces of the base particles (A1) under the action of a mechanical impact force to form particles (A2), the modifier particles (B) being particles selected from the group consisting of charge-controlling particles releasing particles, colored particles, charge-suppressing particles and abrasive particles; and passing the particles (A2) and shell-forming resin particles (C) having a particle size ratio of 0.2 or less with respect to the particles (A2) through an impact zone having a minimum clearance of 0.
    Type: Grant
    Filed: October 4, 1989
    Date of Patent: June 1, 1993
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masuo Yamazaki, Atsuko Kobayashi, Hitoshi Kanda, Yusuke Karami, Yasuhide Goseki, Yasutaka Akashi
  • Patent number: 5178460
    Abstract: A continuous mixing device for mixing continuously powder, comprising a casing having a mixing chamber inside of the device, a rotary shaft included within said casing, a rotatable stirring blade axially supported with said rotary shaft, and a fixed blade fixed inside of said casing, wherein said stirring blades and fixed blades are provided in plural numbers. A process for producing a toner composition of developing electrostatic latent images, comprising introducing colored particles having at least a binder resin and a colorant, and a powdery additive into a continuous mixing device, said continuous mixing device comprising a casing having a mixing chamber inside of the device, a rotary shaft included within said casing, a rotatably stirring blade axially supported with said rotary shaft, and a fixed blade fixed inside of said casing, wherein said stirring blades and fixed blades are provided in plural numbers; and mixing the colored particles and the powdery additive to obtain a toner composition.
    Type: Grant
    Filed: October 30, 1991
    Date of Patent: January 12, 1993
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hitoshi Kanda, Atsuko Kobayashi
  • Patent number: 5165549
    Abstract: A separator for classifying powder with air current comprises at least a classifying chamber and an introducing section for introducing powder into the classifying chamber, a powder feeding inlet for feeding powder formed at the upper portion of the classifying chamber, a cone-shaped classifying plate with a high central portion formed at the lower portion of the classifying chamber, a coarse powder discharging outlet for discharging coarse powder provided at the lower brim outer periphery of the classifying plate, a fine powder discharging outlet for discharging fine powder provided at the central portion of the classifying plate, a gas inflower for dispersing powder by whirling gas provided at the upper outer periphery of the classifying chamber, and a gas inflow inlet for creating a whirling current of gas for classifying powder provided at the lower portion of the classifying chamber.
    Type: Grant
    Filed: October 7, 1991
    Date of Patent: November 24, 1992
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hitoshi Kanda, Toshiaki Sasaki, Masayoshi Kato, Satoshi Mitsumura
  • Patent number: 5111998
    Abstract: A toner for developing an electrostatic latent image is produced by classifying a pulverized feed material in a first classifying means into coarse powder and fine powder; pulverizing the coarse powder and feeding back the pulverized product to the first classifying means; introducing the fine powder to a second classifying means having a multi-division classification zone divided into at least three sections, where it is classified into a coarse powder portion, a median powder portion, and a fine powder portion; and feeding back the coarse powder to said pulverizing means or first classifying means. The median powder has a volume average particle diameter of from 4 .mu.m to 10 .mu.m and a coefficient of variation of number distribution, represented by A, satisfying the following condition: 20.ltoreq.A.ltoreq.45, and the weights B, C, F, G and M are controlled to satisfy the expressions: 0.3 .ltoreq.weight B/weight C.ltoreq.0.8, 0.2.ltoreq.weight G/weight C.ltoreq.0.7 and 0.8.ltoreq.
    Type: Grant
    Filed: March 27, 1991
    Date of Patent: May 12, 1992
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hitoshi Kanda, Yusuke Yamada, Masayoshi Kato, Yasuhide Goseki, Satoshi Mitsumura
  • Patent number: 5087546
    Abstract: A continuous mixing device for mixing continuously powder, comprising a casing having a mixing chamber inside of the device, a rotary shaft included within said casing, a rotatable stirring blade axially supported with said rotary shaft, and a fixed blade fixed inside of said casing, wherein said stirring blades and fixed blades are provided in plural numbers. A process for producing a toner composition of developing electrostatic latent images, comprising introducing colored particles having at least a binder resin and a colorant, and a powdery additive into a continuous mixing device, said continuous mixing device comprising a casing having a mixing chamber inside of the device, a rotary shaft included within said casing, a rotatable stirring blade axially supported with said rotary shaft, and a fixed blade fixed inside of said casing, wherein said stirring blades and fixed blades are provided in plural numbers; and mixing the colored particles and the powdery additive to obtain a toner composition.
    Type: Grant
    Filed: December 5, 1989
    Date of Patent: February 11, 1992
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hitoshi Kanda, Atsuko Kobayashi