Patents by Inventor Yohichiroh Watanabe

Yohichiroh Watanabe 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: 9023572
    Abstract: A method for producing resin particles, including ejecting a liquid containing at least a resin in the form of droplets from a droplet ejecting unit having a plurality of holes provided in a part of a flow channel for feeding the liquid containing at least a resin, and drying and solidifying the ejected droplets so as to obtain the resin particles, while the ejected droplets are transported by a primary transport air flow flowing in the direction in which the droplets are ejected, wherein the ejected droplets are further transported by a secondary transport air flow which transports the ejected droplets in a different direction from a direction in which the primary transport air flow flows, and wherein a smaller angle of angles formed between a velocity vector of the primary transport air flow and a velocity vector of the secondary transport air flow is less than 120 degrees.
    Type: Grant
    Filed: May 21, 2010
    Date of Patent: May 5, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Takahiro Honda, Yohichiroh Watanabe, Yasutada Shitara, Yoshihiro Norikane
  • Patent number: 8758973
    Abstract: An apparatus for producing a toner, including a liquid droplet-forming unit configured to discharge a toner composition liquid containing at least a resin and a colorant at a uniform discharge speed from a plurality of discharge holes some of which have different shapes from each other to thereby form liquid droplets, and a particle-forming unit configured to solidify the liquid droplets of the toner composition liquid to thereby form particles.
    Type: Grant
    Filed: September 16, 2011
    Date of Patent: June 24, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Keiji Makabe, Yohichiroh Watanabe, Minoru Masuda, Yasutada Shitara, Yoshihiro Norikane
  • Patent number: 8758972
    Abstract: A toner produced by a method including dissolving or dispersing toner components comprising a resin, a colorant, and a release agent in a solvent to prepare a toner components liquid, discharging the toner components liquid from multiple nozzles provided on a thin film by vibrating the thin film by a mechanical vibration unit to form liquid droplets, and drying the liquid droplets into solid particles of the toner. The particle diameter distribution that is a ratio of a weight average particle diameter to a number average particle diameter of the toner is between 1.00 and 1.15, and a weight average particle diameter of the release agent in the toner is between 1% and 30% of an aperture diameter of the nozzle.
    Type: Grant
    Filed: July 6, 2009
    Date of Patent: June 24, 2014
    Assignee: Ricoh Company, Limited
    Inventors: Takahiro Honda, Yohichiroh Watanabe, Yoshihiro Norikane, Shinji Ohtani
  • Patent number: 8748072
    Abstract: A method for producing a toner, including ejecting a toner composition liquid containing at least a resin and a colorant periodically from a plurality of nozzles into a chamber using a vibration unit, so as to form droplets in a gas phase; and solidifying the droplets, wherein the droplets are transported by transport air flow selected from at least one of vertical downward air flow and rotational air flow, and the method can prevent toner particles from aggregation.
    Type: Grant
    Filed: June 22, 2009
    Date of Patent: June 10, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Takahiro Honda, Yukio Tabata, Yohichiroh Watanabe, Kazumi Suzuki, Shinji Ohtani, Yoshihiro Norikane
  • Patent number: 8709697
    Abstract: A method of manufacturing a toner including supplying a fluid containing a resin and a coloring agent to a retaining member including a film having multiple discharge orifices, discharging droplets of the fluid from the multiple discharge orifices at a speed of from 2 to 4 m/s by applying a pulse voltage having a trapezoid waveform to a piezoelectric body having a surface provided substantially parallel to the film to move the surface in a direction away from the film relative to a reference position of the surface followed by holding the surface there for a predetermined time, and bringing the surface back to the reference position; and solidifying droplets of the fluid discharged from the multiple discharge orifices to form mother particles.
    Type: Grant
    Filed: July 12, 2010
    Date of Patent: April 29, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshihiro Norikane, Yohichiroh Watanabe, Masaru Ohgaki, Shinji Aoki, Yasutada Shitara, Andrew Mwaniki Mulwa
  • Patent number: 8663888
    Abstract: The present invention provides a toner including: a colorant, and a binder resin, wherein the toner is fixed on a recording medium using a fixing liquid containing a softening agent for softening the toner, and wherein a weight average molecular weight of a THF soluble fraction of the toner in a molecular weight distribution measured by gel permeation chromatography (GPC) is 3,000 to 8,300; and a glass transition temperature of the toner measured by differential scanning calorimetry (DSC) is 50° C. to 70° C.
    Type: Grant
    Filed: December 20, 2010
    Date of Patent: March 4, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Yasutada Shitara, Yohichiroh Watanabe, Yasuo Katano, Shinya Nakayama, Ryota Inoue, Yoshihiro Moriya, Akiyoshi Sabu, Shingo Sakashita, Yukiko Nakajima
  • Patent number: 8568628
    Abstract: A method of preparing a toner, including periodically dripping and discharging droplets of a toner constituent liquid comprising a resin and a colorant with a dripper comprising a thin film comprising plural nozzles configured to discharge the droplets, and an electromechanical converter configured to oscillate the thin film; and solidifying the droplets to form toner particles, wherein the nozzle has an aperture discharging the droplet, having a circular or an ellipsoidal cross-sectional shape and cross-sectional area smaller than a cross-sectional area of another aperture contacting the toner constituent liquid.
    Type: Grant
    Filed: May 14, 2008
    Date of Patent: October 29, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshihiro Norikane, Shinji Ohtani, Yohichiroh Watanabe, Kazumi Suzuki, Takahiro Honda
  • Publication number: 20130196266
    Abstract: A toner produced by dissolving or dispersing toner components comprising a binder resin, a colorant, and a charge controlling agent in an organic solvent to prepare a toner components liquid, forming liquid droplets of the toner components liquid in a gas phase, and solidifying the liquid droplets into toner particles of the toner. The charge controlling agent includes a polycondensation reaction product of a phenol with an aldehyde.
    Type: Application
    Filed: March 13, 2013
    Publication date: August 1, 2013
    Inventors: Yohichiroh Watanabe, Kazumi Suzuki, Takahiro Honda, Shinji Ohtani, Yoshihiro Norikane
  • Patent number: 8445171
    Abstract: A method of preparing a toner, including dripping a toner constituent liquid comprising an organic solvent; and toner constituents comprising a resin and a colorant, which are dissolved or dispersed in the organic solvent through a nozzle to form a droplet; and removing the organic solvent from the droplet, wherein the droplet is dried while contacted with a first de-solvent gas comprising steam in a pre-heated period and at least a part of a constant-rate drying period, or the droplet is dried at least in a pre-heated period and a constant-rate drying period, which include two stages including a first stage and a second stage, wherein the droplet is contacted with the first de-solvent gas including steam in the first stage and a second de-solvent gas having a dew point not greater than ?10° C. under ordinary pressure in the second stage.
    Type: Grant
    Filed: August 7, 2008
    Date of Patent: May 21, 2013
    Assignee: Ricoh Company, Limited
    Inventors: Kazumi Suzuki, Yohichiroh Watanabe
  • Patent number: 8445172
    Abstract: A method for producing a toner, containing: ultrasonically vibrating a liquid toner composition in which a toner material containing at least a binder resin and a colorant is dissolved or dispersed in a solvent; introducing the liquid toner composition to a liquid chamber, and ejecting the liquid toner composition as droplets from an ejecting plate having a plurality of holes and disposed on one surface of the liquid chamber; and drying and solidifying the droplets so as to produce a toner, wherein the ultrasonically vibrating is performed before the introducing the liquid toner composition to the liquid chamber.
    Type: Grant
    Filed: March 5, 2010
    Date of Patent: May 21, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Yasutada Shitara, Yoshihiro Norikane, Yohichiroh Watanabe, Andrew Mwaniki Mulwa
  • Patent number: 8329373
    Abstract: A method and an apparatus for producing toner are provided. A fluid comprising a resin and a colorant is supplied to a retention member that includes a film on which multiple discharge openings are formed. The fluid which is supplied to the retention member is resonated so that liquid droplets thereof are discharged from the multiple openings. The liquid droplets which are discharged from the multiple openings are solidified to form mother particles of a toner.
    Type: Grant
    Filed: October 23, 2009
    Date of Patent: December 11, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshihiro Norikane, Shinji Aoki, Masaru Ohgaki, Yohichiroh Watanabe, Takahiro Honda, Andrew Mwaniki Mulwa, Yuko Sekiguchi
  • Patent number: 8318400
    Abstract: A method of preparing a toner, including periodically discharging a toner constituent liquid from plural nozzles having the same aperture diameter with a mechanical oscillator, wherein the toner constituent liquid includes: a binder resin, a colorant, and an organic solvent, wherein the binder resin and the colorant are dissolved or dispersed in the organic solvent; forming a droplet of the toner constituent liquid in a gas phase; and solidifying the droplet, wherein the aperture diameter is from 3 to 30 ?m, and the binder resin has a ratio (Mw/Mn) of a weight-average molecular weight (Mw) to a number-average molecular weight (Mn) of THF (tetrahydrofuran)-soluble components therein of from 1.5 to 15 in a molecular weight distribution measured by GPC (gel permeation chromatography), and a ½ flow temperature (Tm) of from 114 to 149° C.
    Type: Grant
    Filed: November 4, 2008
    Date of Patent: November 27, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Yohichiroh Watanabe, Kazumi Suzuki, Takahiro Honda, Shinji Ohtani, Yoshihiro Norikane
  • Patent number: 8263304
    Abstract: A method for producing a toner including periodically forming and discharging liquid droplets of a toner composition liquid containing at least a resin, a releasing agent and a colorant from a plurality of nozzles formed in a thin film which is provided in a reservoir for the toner composition liquid, by vibrating the thin film using a mechanically vibrating unit, and forming toner particles by solidifying the liquid droplets, wherein the forming toner particles comprises primarily drying the liquid droplets under a stream of dry gas containing an organic solvent whose partial pressure is equal to or higher than 1/10 of a saturated vapor pressure thereof but is equal to or lower than the saturated vapor pressure, the saturated vapor pressure being that at a drying temperature; and secondarily drying the primarily dried liquid droplets for solidification while the organic solvent is being evaporated.
    Type: Grant
    Filed: August 31, 2009
    Date of Patent: September 11, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Takahiro Honda, Yohichiroh Watanabe, Kazumi Suzuki
  • Patent number: 8252500
    Abstract: The present invention provides a toner containing at least two binder resins composed of at least a resin A and a resin B which are incompatible with each other, and a colorant, wherein the toner has an average circularity of 0.93 to 0.98 and is produced by atomizing a toner composition liquid in a vapor phase to form liquid droplets and solidifying the liquid droplets, and the toner composition liquid is prepared by dissolving or dispersing the at least two binder resins and the colorant in an organic solvent.
    Type: Grant
    Filed: June 12, 2008
    Date of Patent: August 28, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Yohichiroh Watanabe, Kazumi Suzuki, Shinji Ohtani, Takahiro Honda, Yoshihiro Norikane
  • Publication number: 20120070777
    Abstract: An apparatus for producing a toner, including a liquid droplet-forming unit configured to discharge a toner composition liquid containing at least a resin and a colorant at a uniform discharge speed from a plurality of discharge holes some of which have different shapes from each other to thereby form liquid droplets, and a particle-forming unit configured to solidify the liquid droplets of the toner composition liquid to thereby form particles.
    Type: Application
    Filed: September 16, 2011
    Publication date: March 22, 2012
    Inventors: Keiji Makabe, Yohichiroh Watanabe, Minoru Masuda, Yasutada Shitara, Yoshihiro Norikane
  • Patent number: 8137087
    Abstract: A method of preparing a toner, including periodically dripping and discharging a droplet of a toner constituent liquid including a resin and a colorant; and solidifying and granulating the droplet, wherein the dripper includes a thin film including plural nozzles; and an oscillator including an oscillation generator generating an oscillation; and an oscillation amplifier, including an oscillation surface facing the thin film in parallel therewith, amplifying the oscillation, and wherein the toner constituent liquid is fed between the thin film and the oscillation surface.
    Type: Grant
    Filed: March 26, 2008
    Date of Patent: March 20, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshihiro Norikane, Shinji Ohtani, Yohichiroh Watanabe, Kazumi Suzuki
  • Patent number: 8124308
    Abstract: Toner and a developer which are excellent in cleaning property and fixing property at low temperature, and capable of forming images with high quality are provided, along with a method for their production. A toner producing method involves dispersing and/or emulsifying an oil phase or a monomer phase containing a toner composition and/or a toner composition precursor in a water-based medium to granulate, wherein the toner has an average circularity of 0.925 to 0.970, and the toner composition and/or the toner composition precursor has a layered inorganic material in which at least a part of interlayer ions in the layered inorganic material has been exchanged with organic ions.
    Type: Grant
    Filed: December 13, 2010
    Date of Patent: February 28, 2012
    Assignee: Ricoh Company. Ltd.
    Inventors: Naohiro Watanabe, Shigeru Emoto, Yohichiroh Watanabe, Masahide Yamada, Tsunemi Sugiyama, Masahiro Ohki, Akinori Saitoh, Ryota Inoue, Osamu Uchinokura, Junichi Awamura
  • Patent number: 8110332
    Abstract: Provided are an electrophotographic toner and a method for producing the electrophotographic toner that satisfy high image quality, cleaning stability, and high productivity. The electrophotographic toner is produced by spray-drying a toner ingredient-containing liquid, wherein the toner ingredient-containing liquid dissolves or disperses at least a resin, a low molecular mass organic material, and a colorant in an organic solvent, the resin is soluble in the organic solvent, the low molecular mass organic material is a crystalline compound or a composition of crystalline compounds that is soluble in the organic solvent, the toner ingredient-containing liquid contains substantially no particles having a particle diameter of 500 nm or more, the crystalline compound or the composition of crystalline compounds crystallizes upon spray-drying to deform toner particles into a circularity of 0.93 or higher to 0.98 or less, and volume average particle diameter of the toner particles is 3.
    Type: Grant
    Filed: February 25, 2008
    Date of Patent: February 7, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Kazumi Suzuki, Yohichiroh Watanabe, Takahiro Honda, Yoshihiro Norikane, Shinji Ohtani, Tsuyoshi Sugimoto
  • Patent number: 8105742
    Abstract: A method for manufacturing a toner, including periodically forming liquid droplets of a toner constituent liquid comprising a resin and a colorant by vibrating a thin film having a plurality of holes provided on a retention part thereof to discharge the liquid droplets of the toner constituent liquid from the plurality of holes and forming toner particles by solidifying the liquid droplets discharged from the plurality of holes. In periodically forming the liquid droplets of the toner constituent liquid, a flow of gas in a direction of discharge of the liquid droplets is formed by a gas flow generation unit provided downstream from the thin film relative to the direction of discharge of the liquid droplets, including a tapered part forming an aperture corresponding to a hole formation area of the thin film.
    Type: Grant
    Filed: May 15, 2008
    Date of Patent: January 31, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshihiro Norikane, Shinji Ohtani, Yohichiroh Watanabe, Kazumi Suzuki
  • Patent number: 8034526
    Abstract: A method for manufacturing a toner, including: dissolving or dispersing toner constituents including a resin, a colorant, a release agent, and a graft polymer including a polyolefin resin unit and a vinyl resin unit in a solvent, to prepare a toner constituent liquid; supplying the toner constituent liquid to a retention part configured to retain the toner constituent liquid; discharging the toner constituent liquid from the retention part to a granulation space through plural holes arranged on the retention part, while exciting the toner constituent liquid by a vibration means in contact with a part of the retention part, so that the discharged columnar toner constituent liquid is constricted to form liquid droplets; and converting the liquid droplets into solid toner particles; together with a toner manufactured by the above method.
    Type: Grant
    Filed: September 7, 2007
    Date of Patent: October 11, 2011
    Assignee: Ricoh Company Limited
    Inventors: Yohichiroh Watanabe, Shinji Ohtani, Yoshihiro Norikane, Yasuaki Iwamoto, Yasutada Shitara, Kazumi Suzuki, Takahiro Honda