Patents by Inventor Akinori Saitoh

Akinori Saitoh 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).

  • Publication number: 20110223530
    Abstract: A toner is provided including a binder resin and a wax having primarily C—H and C—C bonds, and having a melting point of 50 to 90° C., wherein the wax is present in a surface portion of the toner in an amount of from 0.1 to 4.0% by weight, wherein the amount of the wax is determined by Fourier transform infrared spectroscopy attenuated total reflectance (FTIR-ATR); and the use of the toner in an image forming method, image forming apparatus, developer and toner cartridge containing the toner.
    Type: Application
    Filed: May 20, 2011
    Publication date: September 15, 2011
    Inventors: Ryota Inoue, Shigeru Emoto, Naohiro Watanabe, Masahide Yamada, Akinori Saitoh, Masahiro Ohki, Tsunemi Sugiyama, Shinichi Wakamatsu, Takayuki Yoshii, Eiji Sawamura
  • Patent number: 8007977
    Abstract: A toner satisfying at least one of the following relationships: 10° C.<(T1?T2)<60° C. and 0<Q2/Q1<2/3 wherein T1 represents a glass transition temperature of the toner and Q1 represents an endothermic quantity at a melting point thereof before melting when heated from ?20° C. to 150° C. at a heating speed of 10° C./min, and T2 represents a glass transition temperature thereof and Q2 represents a an endothermic quantity at a melting point thereof after melting after heated from ?20° C. to 150° C. at a heating speed of 10° C./min, cooled to ?20° C. at a cooling speed of 10° C./min and heated again at a heating speed of 10° C./min.
    Type: Grant
    Filed: September 14, 2005
    Date of Patent: August 30, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Ryota Inoue, Sonoh Matsuoka, Chiaki Tanaka, Naohiro Watanabe, Masahide Yamada, Masahiro Ohki, Akinori Saitoh
  • Patent number: 7989131
    Abstract: A toner is provided including a binder resin and a wax having primarily C—H and C—C bonds, and having a melting point of 50 to 90° C., wherein the wax is present in a surface portion of the toner in an amount of from 0.1 to 4.0% by weight, wherein the amount of the wax is determined by Fourier transform infrared spectroscopy attenuated total reflectance (FTIR-ATR); and the use of the toner in an image forming method, image forming apparatus, developer and toner cartridge containing the toner.
    Type: Grant
    Filed: September 13, 2006
    Date of Patent: August 2, 2011
    Assignee: Ricoh Company Limited
    Inventors: Ryota Inoue, Shigeru Emoto, Naohiro Watanabe, Masahide Yamada, Akinori Saitoh, Masahiro Ohki, Tsunemi Sugiyama, Shinichi Wakamatsu, Takayuki Yoshii, Eiji Sawamura
  • Publication number: 20110177440
    Abstract: A method of manufacturing toner including: preparing a first liquid by dissolving or dispersing toner components including a colorant, a release agent, and one or both of a binder resin and a precursor thereof in an organic solvent; preparing a second liquid having a viscosity of from 50 to 800 mPa·sec when measured with a Brookfield viscometer at a revolution of 60 rpm and a temperature of 25° C., by emulsifying the first liquid in an aqueous medium; and evaporating the organic solvent from the second liquid by flowing down the second liquid as a liquid film from a supply part along an inner wall surface of a pipe depressurized to 70 kPa or less in substantially a vertical direction, and heating the liquid film at not higher than a glass transition temperature of the binder resin by contact with the inner wall surface of the pipe in a heating part. A heat insulating part is provided between the supply part and the heating part.
    Type: Application
    Filed: January 19, 2011
    Publication date: July 21, 2011
    Inventors: Hiroshi Yamada, Akinori Saitoh, Masahide Yamada
  • Patent number: 7932007
    Abstract: There are provided: a method for producing a toner containing to granulate a toner and to subjecting the granulated toner to at least washing with an alkali washing solution, in which the total organic carbon amount extractable from the alkali-washed toner is 200 ppm/g or less; a toner comprising polyester in which the total organic carbon amount extractable from the toner is 200 ppm/g or less, under the condition that the toner is subjected to washing with the alkali washing solution before extracting; and an image-forming method using such a toner.
    Type: Grant
    Filed: September 20, 2005
    Date of Patent: April 26, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Yamashita, Chiaki Tanaka, Yohichiroh Watanabe, Tsunemi Sugiyama, Masahiro Ohki, Sonoh Matsuoka, Masahide Yamada, Naohiro Watanabe, Akinori Saitoh, Ryota Inoue
  • Publication number: 20110086308
    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: Application
    Filed: December 13, 2010
    Publication date: April 14, 2011
    Inventors: Naohiro WATANABE, Shigeru Emoto, Yohichiroh Watanabe, Masahide Yamada, Tsunemi Sugiyama, Masahiro Ohki, Akinori Saitoh, Ryota Inoue, Osamu Uchinokura, Junichi Awamura
  • Publication number: 20110033796
    Abstract: A method of preparing a toner, including dissolving toner constituents including a binder resin or a binder resin precursor, a colorant and a release agent in an organic solvent to prepare a first liquid; emulsifying the first liquid in an aqueous medium to prepare a second liquid having a viscosity of from 50 to 800 mPa·sec; and at least flowing the second liquid almost vertically down along the wall surface of a pipe in which the air pressure is depressurized to 70 kPa or less twice while keeping a temperature of the second liquid not higher than a Tg of the parent particle through the wall surface thereof to volatilize the organic solvent, wherein a solid content of a slurry after volatilized is from 15 to 50%, and a ratio of the solid content to a solid content of a slurry before volatilized is from 1.05 to 2.00.
    Type: Application
    Filed: July 6, 2010
    Publication date: February 10, 2011
    Inventors: Hiroshi YAMADA, Akinori Saitoh, Masahide Yamada
  • Publication number: 20100285402
    Abstract: A toner is provided which includes a first binder resin, a second binder resin that is a reaction product of a compound having an active hydrogen group with a polymer reactive with the active hydrogen group, a colorant, and a release agent. The toner includes the second binder resin in an amount of from 6.4 to 40.9% by weight, and the reaction product includes organic-solvent-insoluble components in an amount of from 20 to 95% by weight. A method of manufacturing the toner is also provided.
    Type: Application
    Filed: May 10, 2010
    Publication date: November 11, 2010
    Inventors: Akinori Saitoh, Masahide Yamada, Hiroshl Yamada
  • Patent number: 7824834
    Abstract: A toner including a binder resin; a colorant; a release agent; and a modified layered inorganic material in which at least part of interlayer ions is modified with an organic ion, wherein the toner has a volume average particle diameter (Dv) of 3 to 7 ?m and a ratio (Dv/Dn) of the volume average particle diameter (Dv) to a number average particle diameter (Dn) of the toner of 1.00 to 1.30, and wherein the release agent is included in the toner in an amount (A) of 1 to 10% by weight, and the ratio (B/A) of the amount (A) to the amount (B) of the release agent included in a classified toner in units of percent by weight is 0.7 to 1.3, wherein the classified toner satisfies the relationship (Dv?/Dn??1)/(Dv/Dn?1)?¾wherein Dv? and Dn? respectively represent the volume and number average particle diameters of the classified toner.
    Type: Grant
    Filed: September 14, 2007
    Date of Patent: November 2, 2010
    Assignee: Ricoh Company Limited
    Inventors: Junichi Awamura, Akinori Saitoh, Masahide Yamada, Toyoshi Sawada, Takuya Seshita, Tomomi Suzuki
  • Patent number: 7824831
    Abstract: A toner including a binder resin, a colorant, and a release agent is provided. The difference in absorbance ratio between the toner heated for 1 minute in an atmosphere of 100° C. and the toner stored in an atmosphere of 23° C. is from 0.1 to 0.2. The absorbance ratio is a ratio of an absorbance specific to the release agent (such as at 2850 cm?1 for a wax) to an absorbance specific to the binder resin (such as at 828 cm?1 for a polyester based binder resin), as measured by a Fourier transform infrared-total reflectance (FTIR-ATR) method.
    Type: Grant
    Filed: September 3, 2008
    Date of Patent: November 2, 2010
    Assignee: Ricoh Company Limited
    Inventors: Masahide Yamada, Akinori Saitoh, Osamu Uchinokura, Junichi Awamura
  • Patent number: 7820350
    Abstract: A toner containing a colorant, and a binder resin, wherein the toner is prepared by dissolving or dispersing a colorant, a precursor of the binder resin having a site capable of reacting with an active hydrogen group-containing compound, the active hydrogen group-containing compound, in an organic solvent, to prepare a toner constituent mixture liquid, dispersing or emulsifying the toner constituent mixture liquid, in an aqueous medium while subjecting the precursor to a reaction with the active hydrogen group-containing compound, to prepare a toner dispersion, and removing the organic solvent from the toner dispersion; the binder resin contains a modified polyester having an isocyanate-derived binding site; the Sn content in the toner is 800 ppm or less; the content of a metal which is non Sn and derived from a polyesterified catalyst is 10 ppm to 200 ppm; and the content of a metal which is non Sn and derived from an isocyanated catalyst is 10 ppm to 200 ppm.
    Type: Grant
    Filed: March 16, 2007
    Date of Patent: October 26, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Masahide Yamada, Shigeru Emoto, Naohiro Watanabe, Masahiro Ohki, Akinori Saitoh, Shinichi Wakamatsu
  • Publication number: 20100129748
    Abstract: A toner satisfying at least one of the following relationships: 10° C.<(T1?T2)<60° C. and 0<Q2/Q1<2/3 wherein T1 represents a glass transition temperature of the toner and Q1 represents an endothermic quantity at a melting point thereof before melting when heated from ?20° C. to 150° C. at a heating speed of 10° C./min, and T2 represents a glass transition temperature thereof and Q2 represents a an endothermic quantity at a melting point thereof after melting after heated from ?20° C. to 150° C. at a heating speed of 10° C./min, cooled to ?20° C. at a cooling speed of 10° C./min and heated again at a heating speed of 10° C./min.
    Type: Application
    Filed: January 29, 2010
    Publication date: May 27, 2010
    Inventors: Ryota Inoue, Sonoh Matsuoka, Chiaki Tanaka, Naohiro Watanabe, Masahide Yamada, Masahiro Ohki, Akinori Saitoh
  • Patent number: 7695883
    Abstract: To provide a toner containing an ethyl acetate-soluble polyester component and an ethyl acetate-insoluble polyester component, wherein the toner is granulated in an aqueous medium, the ethyl acetate-insoluble polyester component is obtained by elongating and/or cross-linking a modified polyester resin during granulating and/or after granulating, the modified polyester resin is produced by condensation polymerization of an acid component and at least one type of diol compound selected from aliphatic diol and alicyclic diol in the presence of a catalyst, and the mass average molecular weight of the modified polyester resin is 10,000 to 100,000.
    Type: Grant
    Filed: December 24, 2008
    Date of Patent: April 13, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Masahide Yamada, Ryota Inoue, Naohiro Watanabe, Shigeru Emoto, Masahiro Ohki, Akinori Saitoh, Tsunemi Sugiyama, Shinichi Wakamatsu, Toshiki Nanya, Naohito Shimota, Hiroshi Yamada, Junichi Awamura, Tomomi Suzuki, Kazuyuki Hirai, Kazushige Yasumatsu
  • Patent number: 7670741
    Abstract: A toner containing a toner particle manufactured by dispersing an organic solvent in which a component comprising a polymer having a portion reactive with an active hydrogen group is dispersed or dissolved in an aqueous medium; and reacting the polymer with a compound having at least one active hydrogen group, where the polymer is prepared by reacting an aliphatic polyol, a polyester resin and a diisocyanate compound and has an isocyanate group on at least one end of the polymer.
    Type: Grant
    Filed: March 16, 2007
    Date of Patent: March 2, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Masahide Yamada, Akinori Saitoh, Masahiro Ohki
  • Patent number: 7666563
    Abstract: A toner is provided including a binder resin including at least one polyester resin in an amount of from 50 to 100% by weight, and a colorant having a specific formula, wherein the toner has a shape factor SF-1 of from 120 to 150 and a shape factor SF-2 of from 125 to 180; and a developer using the toner.
    Type: Grant
    Filed: August 31, 2006
    Date of Patent: February 23, 2010
    Assignee: Ricoh Company Limited
    Inventors: Masahiro Ohki, Naohiro Watanabe, Ryota Inoue, Masahide Yamada, Akinori Saitoh, Shigeru Emoto, Tsunemi Sugiyama, Shinichi Wakamatsu
  • Publication number: 20090280421
    Abstract: A method of manufacturing a toner including dispersing a binder resin, a coloring agent and a releasing agent in an organic solvent to obtain an oil phase; dispersing the oil phase in an aqueous medium with a shearing force to obtain a dispersion emulsion; wherein the shearing force is made by a screen or vessel that is situated around a rotor, the screen spinning in a direction opposite to the direction that the rotor spins. Toner produced. Method of using the toner.
    Type: Application
    Filed: May 8, 2009
    Publication date: November 12, 2009
    Inventors: Junichi Awamura, Akinori Saitoh, Osamu Uchinokura, Masahide Yamada, Tomomi Suzuki
  • Publication number: 20090269692
    Abstract: A method of manufacturing the toner comprising dispersing at least one of a binder resin or a precursor thereof, a coloring agent and a releasing agent in an organic solvent to obtain an oil phase,dispersing the oil phase in an aqueous medium with a shearing force to obtain a dispersion emulsion, wherein the dispersion emulsion process has plural stages and the shear speed A of the emulsification process of stage n is faster than the shear speed B of the emulsification process of stage n+1.
    Type: Application
    Filed: April 23, 2009
    Publication date: October 29, 2009
    Inventors: Junichi AWAMURA, Akinori SAITOH, Osamu UCHINOKURA, Tomomi SUZUKI
  • Publication number: 20090226836
    Abstract: A method of manufacturing a toner including granulating mother toner particles in an aqueous medium to obtain a slurry containing the mother toner particles and adjusting a size distribution of the mother toner particles by screening coarse mother toner particles from the slurry with a screen to obtain the toner containing mother toner particulates.
    Type: Application
    Filed: March 6, 2009
    Publication date: September 10, 2009
    Inventors: OSAMU UCHINOKURA, AKINORI SAITOH, JUNICHI AWAMURA, MASAHIDE YAMADA, HIROSHI YAMADA
  • Publication number: 20090214975
    Abstract: A toner prepared by a method including dissolving or dispersing at least at least one member selected from the group consisting of binder resins and precursors thereof, a colorant, a release agent, and a layered inorganic mineral in which ions between its layers are at least partially modified with an organic ion in an organic solvent to prepare a solution or a dispersion which is an oil phase; and dispersing the oil phase in an aqueous medium to prepare an emulsified dispersion in which parent toner particles are granulated, wherein the aqueous medium includes a tertiary amine compound.
    Type: Application
    Filed: February 12, 2009
    Publication date: August 27, 2009
    Inventors: Junichi AWAMURA, Akinori Saitoh, Osamu Uchinokura, Masahide Yamada, Tomomi Suzuki
  • Patent number: 7550245
    Abstract: The object of the present invention is to provide a toner having a uniform composition of toner materials among toner particles, excelling in charge stability, enabling high-quality images without substantially causing fog and toner scattering, and having a small diameter and a narrow particle size distribution. The present invention also provides an effective production method of the toner, and an image forming method and the like using the toner. For this end, the present invention provides a method for producing a toner in which a dissolved and dispersed solution of toner materials is dispersed as dispersion particles in an aqueous medium containing no organic resin fine particles to prepare an oil droplet-in-water dispersion, and organic resin fine particles are added to the oil droplet-in-water dispersion to thereby granulate a toner in the presence of the organic resin fine particles.
    Type: Grant
    Filed: December 22, 2005
    Date of Patent: June 23, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Ryota Inoue, Shigeru Emoto, Yohichiroh Watanabe, Naohiro Watanabe, Masahide Yamada, Akinori Saitoh, Masahiro Ohki, Tsunemi Sugiyama