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: 20090155709
    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. A toner prepared by dispersing and/or emulsifying an oil phase or a monomer phase comprising 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: March 5, 2007
    Publication date: June 18, 2009
    Applicant: RICOH COMPANY, LTD.
    Inventors: Naohiro Watanabe, Shigeru Emoto, Yohichiroh Watanabe, Masahide Yamada, Tsunemi Sugiyama, Masahiro Ohki, Akinori Saitoh, Ryota Inoue, Osamu Uchinokura, Junichi Awamura
  • Publication number: 20090142682
    Abstract: A toner including a binder resin, a coloring agent, a releasing agent and a modified laminar inorganic mineral, wherein the toner is granulated by dispersing the coloring agent, the releasing agent, the modified laminar inorganic mineral and at least one of the binder resin and a precursor thereof in an organic solvent to form an oil phase, dispersing the oil phase in an aqueous medium to obtain a dispersion emulsion and removing solvents therefrom, and the toner satisfies the following relationship (1): 0.2?{1/Dv (?m)}×Sb (m2/g)?1.4, where Dv represents a volume average particle diameter of the toner, and Sb represents a BET specific surface area of the toner.
    Type: Application
    Filed: December 1, 2008
    Publication date: June 4, 2009
    Inventors: Akinori Saitoh, Osamu Uchinokura, Masahide Yamada, Tomomi Suzuki, Junichi Awamura
  • Publication number: 20090142690
    Abstract: A method of manufacturing a toner including forming a wax liquid dispersion in which a wax is dispersed in an organic solvent (A1), mixing an organic layer including the wax liquid dispersion, a binder resin and an organic solvent (A) to form an oil phase and dispersing and emulsifying the oil phase in an aqueous medium to obtain an emulsified liquid dispersion, wherein the aspect ratio average of the wax in the wax liquid dispersion is from 0.3 to 0.7 and the toner includes toner particles satisfying the following relationship (1) in an amount of 20% by number or smaller based on all toner particles: 0.5<D2/D1, relationship (1), where D1 represents the major diameter (D1) of the toner and D2 represents the major diameter of the wax.
    Type: Application
    Filed: November 28, 2008
    Publication date: June 4, 2009
    Inventors: Junichi AWAMURA, Akinori Saitoh, Masahide Yamada, Osamu Uchinokura, Tomomi Suzuki
  • Patent number: 7531279
    Abstract: A toner manufacturing method is provided including emulsion-polymerizing monomers including an aromatic vinyl monomer, to prepare a particulate resin dispersion; mixing the particulate resin dispersion and a colorant dispersion including a black metallic material, to prepare an aggregation dispersion including aggregated resin particles including the colorant therein; heating the aggregation dispersion to a temperature of not less than a glass transition temperature of the particulate resin to unite each of the aggregated particles to prepare a toner dispersion; and washing the toner dispersion to obtain the toner; a toner manufactured by the above method, and a developer using the toner.
    Type: Grant
    Filed: May 9, 2006
    Date of Patent: May 12, 2009
    Assignee: Ricoh Company Limited
    Inventors: Naohiro Watanabe, Shigeru Emoto, Chiaki Tanaka, Masahide Yamada, Akinori Saitoh, Masahiro Ohki, Ryota Inoue
  • Publication number: 20090117480
    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: Application
    Filed: December 24, 2008
    Publication date: May 7, 2009
    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: 7504188
    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: November 12, 2007
    Date of Patent: March 17, 2009
    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
  • Publication number: 20090061345
    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: Application
    Filed: September 3, 2008
    Publication date: March 5, 2009
    Inventors: Masahide YAMADA, Akinori Saitoh, Osamu Uchinokura, Junichi Awamura
  • Publication number: 20080311500
    Abstract: A toner including toner particles 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 includes the release agent in an amount of from 3 to 6% by weight based on the total weight of the toner, and concentration of the modified layered inorganic material in a surface portion of the toner is greater than the average concentration thereof in the toner, and wherein the toner is subjected to FTIR-ATR, the ratio (P2850/P828) of the strength of the peak at 2850 cm?1 to that of the peak at 828 cm?1, is from 0.03 to 0.10. An image forming apparatus and a process cartridge which form a toner image using the toner.
    Type: Application
    Filed: March 4, 2008
    Publication date: December 18, 2008
    Inventors: Masahide YAMADA, Osamu Uchinokura, Akinori Saitoh, Junichi Awamura, Tomomi Suzuki
  • Patent number: 7459255
    Abstract: An object of the present invention is to provide a toner having small-sized and potato-shaped particles created from multiple coherent spherical particles for excellent cleaning ability and high image quality, an image-forming method that realizes high image quality using the toner, and the like. To this end, there is provided a toner, which is produced by granulating toner materials as an organic phase comprising at least a binder resin and a colorant in an aqueous medium and has potato-shaped particles created from multiple coherent primary oil droplets of the organic phase in the aqueous medium.
    Type: Grant
    Filed: September 16, 2005
    Date of Patent: December 2, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Chiaki Tanaka, Naohiro Watanabe, Masahiro Ohki, Masahide Yamada, Akinori Saitoh, Sonoh Matsuoka, Ryota Inoue, Shigeru Emoto
  • Patent number: 7449273
    Abstract: A toner including a binder resin comprising a polyester resin in an amount of from 50 to 100% by weight, wherein the polyester resin includes an unsaturated polyester resin which is preferably a crystalline polyester resin; a colorant; and a fatty acid metal salt which is preferably microencapsulated. A method for preparing a toner including forming particles of a toner composition including at least a binder resin including a polyester resin in an amount of from 50 to 100% by weight and a colorant, in an aqueous medium to prepare a dispersion of a particulate material, wherein the polyester resin includes an unsaturated polyester resin; drying the particulate material; and mixing a fatty acid metal salt with the particulate material to subject double bonds of the unsaturated polyester resin to oxidation polymerization.
    Type: Grant
    Filed: August 4, 2005
    Date of Patent: November 11, 2008
    Assignee: Ricoh Company, Limited
    Inventors: Masahiro Ohki, Naohiro Watanabe, Ryota Inoue, Akinori Saitoh, Sonoh Matsuoka, Masahide Yamada, Chiaki Tanaka
  • Publication number: 20080227018
    Abstract: To provide a toner containing toner particles, wherein each toner particle contains at least: a releasing agent having an average dispersed particle diameter of 0.1 to 0.5 ?m; and a modified layered inorganic mineral in which at least a part of ions present in between layers of a layered inorganic mineral is replaced with an organic ion, wherein the toner has a ratio A/B of 0.2 to 2.0 where A denotes the average dispersed particle diameter of the releasing agent and B denotes an average dispersed particle diameter of the modified layered inorganic mineral, or a proportion of the dispersed particles of the releasing agent having a diameter of 1 ?m or more in the dispersed particles of the releasing agent having a diameter of 0.5 ?m or more is 20% by number or less.
    Type: Application
    Filed: March 12, 2008
    Publication date: September 18, 2008
    Inventors: Junichi Awamura, Osamu Uchinokura, Akinori Saitoh, Masahide Yamada, Tomomi Suzuki
  • Publication number: 20080213682
    Abstract: Provided is a toner for developing electrostatic image, comprising particles of oil phase containing at least a toner composition and/or toner composition precursor in an aqueous medium, wherein the toner composition and/or toner composition precursor comprises an organic-modified layered inorganic mineral prepared by modifying at least partially an ion of a layered inorganic mineral into an organic ion, and the organic ion-modification ratio X satisfies the relation of 100<X(%)<150 in the organic-modified layered inorganic mineral.
    Type: Application
    Filed: February 29, 2008
    Publication date: September 4, 2008
    Inventors: Akinori SAITOH, Masahide Yamada, Osamu Uchinokura, Junichi Awamura, Tomomi Suzuki, Shinichiro Yagi, Tomio Kondou, Masashi Nagayama, Hitoshi Iwatsuki
  • Publication number: 20080090165
    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: Application
    Filed: November 12, 2007
    Publication date: April 17, 2008
    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
  • Publication number: 20080076055
    Abstract: To provide a developer that includes a carrier and a toner having base particles each containing a binder resin and a paraffin wax, wherein the base particle has a paraffin wax-originated endotherm from 2.0 J/g to 5.5 J/g at an endothermic peak as measured by DSC, an average circularity from 0.94 to 1.00, and a contact area-to-whole projected area ratio from 15% to 40%.
    Type: Application
    Filed: September 17, 2007
    Publication date: March 27, 2008
    Inventors: Toyoshi Sawada, Masahide Yamada, Akinori Saitoh, Tomomi Suzuki, Junichi Awamura, Takuya Seshita
  • Patent number: 7348121
    Abstract: A toner including toner particles comprising a binder resin; and at least two kinds of particulate resins which are located on at least a surface of the toner particles, wherein the toner satisfies at least one of the following relationships (TgA?TgB)?20° C., wherein TgA and TgB represent glass transition temperatures (Tg) of a particulate resin (A) having a highest Tg and a particulate resin (B) having a lowest Tg among the at least two kinds of particulate resins, respectively; and 100,000?Mwc?6,000,000 and 8,000?Mwd?800,000, wherein Mwc and Mwd represent weight average molecular weights (Mw) of a particulate resin (C) having a highest Mw and a particulate resin (D) having a lowest Mw among the at least two kinds of particulate resins, respectively, wherein Mwc>Mwd.
    Type: Grant
    Filed: February 2, 2007
    Date of Patent: March 25, 2008
    Assignee: Ricoh Company Limited
    Inventors: Ryohta Inoue, Naohiro Watanabe, Masahide Yamada, Sonoh Matsuoka, Chiaki Tanaka, Takeshi Takada, Masahiro Ohki, Akinori Saitoh
  • Patent number: 7348117
    Abstract: A toner including toner particles comprising a binder resin; and at least two kinds of particulate resins which are located on at least a surface of the toner particles, wherein the toner satisfies at least one of the following relationships (TgA-TgB)?20° C., wherein TgA and TgB represent glass transition temperatures (Tg) of a particulate resin (A) having a highest Tg and a particulate resin (B) having a lowest Tg among the at least two kinds of particulate resins, respectively; and 100,000?Mwc?6,000,000 and 8,000?Mwd?800,000, wherein Mwc and Mwd represent weight average molecular weights (Mw) of a particulate resin (C) having a highest Mw and a particulate resin (D) having a lowest Mw among the at least two kinds of particulate resins, respectively, wherein Mwc>Mwd.
    Type: Grant
    Filed: August 4, 2004
    Date of Patent: March 25, 2008
    Assignee: Ricoh Company Limited
    Inventors: Ryohta Inoue, Naohiro Watanabe, Masahide Yamada, Sonoh Matsuoka, Chiaki Tanaka, Takeshi Takada, Masahiro Ohki, Akinori Saitoh
  • Publication number: 20080070148
    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)?3/4 wherein Dv? and Dn? respectively represent the volume and number average particle diameters of the classified toner.
    Type: Application
    Filed: September 14, 2007
    Publication date: March 20, 2008
    Inventors: Junichi AWAMURA, Akinori Saitoh, Masahide Yamada, Toyoshi Sawada, Takuya Seshita, Tomomi Suzuki
  • Publication number: 20070218391
    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: Application
    Filed: March 16, 2007
    Publication date: September 20, 2007
    Inventors: Masahide YAMADA, Akinori Saitoh, Masahiro Ohki
  • Publication number: 20070218382
    Abstract: A toner containing a toner particle containing a binder resin, a colorant, a releasing agent and a laminar inorganic mineral in which part or all ions present between layers are modified by organic ions. The toner particle has a structure such that when the particle is heated at a temperature ranging from 65 to 90° C. the releasing agent is melted on the outside of the toner particle to form a particle having a sea-island structure.
    Type: Application
    Filed: March 16, 2007
    Publication date: September 20, 2007
    Inventors: Shigeru Emoto, Akinori Saitoh, Naohiro Watanabe, Masahide Yamada, Masahiro Ohki, Ryota Inoue
  • Publication number: 20070218392
    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: Application
    Filed: March 16, 2007
    Publication date: September 20, 2007
    Inventors: Masahide Yamada, Shigeru Emoto, Naohiro Watanabe, Masahiro Ohki, Akinori Saitoh, Shinichi Wakamatsu