Patents by Inventor Naohiro Watanabe

Naohiro 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: 7618977
    Abstract: Medicaments for the treatment of dermatitis exhibiting a biphasic inflammation reaction or dermatitis induced by repeated exposure to an antigen, having quinazolidone derivatives of formula I or II that are herein defined, are disclosed.
    Type: Grant
    Filed: February 22, 2001
    Date of Patent: November 17, 2009
    Assignee: Asubio Pharma Co., Ltd.
    Inventors: Harukazu Fukami, Yoshiaki Tomimori, Yoshiaki Fukuda, Naohiro Watanabe
  • Publication number: 20090233204
    Abstract: Provided is a toner for image formation, granulated by dispersing, emulsifying, or both dispersing and emulsifying an oil phase containing toner constituting materials in an aqueous medium. The toner constituting materials contain a binder resin, a colorant and a pigment dispersant which is a polyester derivative having an acid value of 28 to 50 mgKOH/g and an amine value of 1 to 50 mgKOH/g, and satisfy the following Expressions 1 and 2, where Expression 1 represents a mass ratio, ? is a glass transition temperature of the binder resin, and ? is a glass transition temperature of a mixture of the binder resin and the pigment dispersant in the ratio of Expression 1. Binder resin:Pigment dispersant=100:5??Expression 1 0° C.?????10° C.
    Type: Application
    Filed: March 13, 2009
    Publication date: September 17, 2009
    Inventors: Naohiro WATANABE, Hiroshi Yamashita, Shinichi Wakamatsu, Tsuyoshi Sugimoto
  • Publication number: 20090214973
    Abstract: A toner is provided that includes a release agent, a colorant, a binder resin including a polyester resin, and a fixing auxiliary component including an ester compound of a fatty acid with an alcohol. The fatty acid includes stearic acid and behenic acid in a total amount of 80% by weight or more. The alcohol includes ethylene glycol in an amount of 80% by weight or more. The ester compound has a hydroxyl value of 10 to 100 mgKOH/g.
    Type: Application
    Filed: February 26, 2009
    Publication date: August 27, 2009
    Applicant: RICOH COMPANY, LIMITED
    Inventors: Tsuyoshi Sugimoto, Hiroshi Yamashita, Naohiro Watanabe, Shinichi Wakamatsu, Masaki Watanabe
  • Patent number: 7575842
    Abstract: A toner producing method is provided, which comprises preparing toner base particles in an aqueous medium, wherein the toner base particles comprise resin fine particles, and forming a coating layer on the surface of the toner base particles, wherein the coating layer is formed by attaching or coating a toner functional substance onto the surface of the toner base particles using at least one of supercritical fluids and sub-supercritical fluids.
    Type: Grant
    Filed: November 13, 2007
    Date of Patent: August 18, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Masayuki Ishii, Chiaki Tanaka, Naohiro Watanabe, Kei Naitoh, Takuya Saito
  • Patent number: 7563555
    Abstract: A toner composition including toner particles including a binder resin including a modified polyester resin, and a second resin having a weight average molecular weight of from 2,000 to 10,000; a colorant; a release agent; and a particulate material which is present at least a surface portion of the toner particles while embedded into the surface portion, wherein the binder resin has a glass transition temperature not lower than 35° C. and lower than 55° C., and wherein the particulate material has an average particle diameter of from 0.002 to 0.2 times that of the toner particles. A developer including the toner composition and a carrier having a layer thereon which includes at least an acrylic resin and a silicone resin, and a method for fixing an image of the toner composition are also provided.
    Type: Grant
    Filed: June 27, 2006
    Date of Patent: July 21, 2009
    Assignee: Ricoh Company Limited
    Inventors: Yohichiroh Watanabe, Masanori Suzuki, Tsunemi Sugiyama, Hiroshi Yamashita, Takuya Saito, Naohiro Watanabe, Masami Tomita, Shigeru Emoto, Shinichiro Yagi, Hiroshi Yamada, Toshiki Nanya, Tadao Takigawa
  • 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
  • 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
  • Patent number: 7541128
    Abstract: A toner composition including toner particles including a binder resin including a modified polyester resin, and a second resin having a weight average molecular weight of from 2,000 to 10,000; a colorant; a release agent; and a particulate material which is present at least a surface portion of the toner particles while embedded into the surface portion, wherein the binder resin has a glass transition temperature not lower than 35° C. and lower than 55° C., and wherein the particulate material has an average particle diameter of from 0.002 to 0.2 times that of the toner particles. A developer including the toner composition and a carrier having a layer thereon which includes at least an acrylic resin and a silicone resin, and a method for fixing an image of the toner composition are also provided.
    Type: Grant
    Filed: September 26, 2003
    Date of Patent: June 2, 2009
    Assignee: Ricoh Company Limited
    Inventors: Yohichiroh Watanabe, Masanori Suzuki, Tsunemi Sugiyama, Hiroshi Yamashita, Takuya Saito, Naohiro Watanabe, Masami Tomita, Shigeru Emoto, Shinichiro Yagi, Hiroshi Yamada, Toshiki Nanya, Tadao Takigawa
  • 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
  • Publication number: 20090104555
    Abstract: The present invention provides a toner containing at least a binder resin and a pigment, wherein the amount of the pigment in the toner is 3.0% by mass to 8.5% by mass, the volume average particle diameter of the toner is 2.0 ?m to 6.0 ?m, and a monochrome image, which has been fixed on a recording medium so that the amount of the toner adhered onto the recording medium is 0.25 mg/cm2, has a reflection density of 1.2 to 2.5.
    Type: Application
    Filed: October 6, 2008
    Publication date: April 23, 2009
    Inventors: Shinichi Wakamatsu, Hiroshi Yamashita, Naohiro Watanabe, Tsuyoshi Sugimoto
  • Publication number: 20090092917
    Abstract: A toner including a binder resin including a polyester resin, a colorant, and a release agent including a polyglycerin ester having a melt viscosity of from 1.0 to 40 mPa·sec at 120° C. and a hydroxyl value of from 0 to 100 mgKOH/g is provided. The polyglycerin ester is an ester of a polyglycerin having an average polymerization degree of from 2 to 10 and an aliphatic acid having 16 to 24 carbon atoms in average.
    Type: Application
    Filed: October 9, 2008
    Publication date: April 9, 2009
    Inventors: Tsuyoshi Sugimoto, Hiroshi Yamashita, Naohiro Watanabe, Shinichi Wakamatsu
  • Publication number: 20090074467
    Abstract: An image forming apparatus including an image bearing member to bear a latent electrostatic image, a charging device to charge the image bearing member, an irradiating device to irradiate the image bearing member with light to form the latent electrostatic image, a developing device to develop the latent electrostatic image with toner to form a visualized image, a transfer device to transfer the visualized image to a recording medium, a lubricant application device to apply a lubricant to the surface of the image bearing member, a cleaning device to clean the surface of the image bearing member, wherein the toner has a ratio A of from 0.3 to 1.7 obtained by the following Relationship (1), particulates P comprising resin particulates and inorganic particulates are added to the toner and the resin particulates P1 have an average primary particle diameter of from 60 to 600 nm, ratio A=Mother toner BET specific surface area/Mother toner volume average particle diameter Relationship (1).
    Type: Application
    Filed: September 12, 2008
    Publication date: March 19, 2009
    Inventors: Takuya Seshita, Masayuki Ishii, Hiroshi Yamashita, Naohiro Watanabe, Shinichi Wakamatsu, Tsuyoshi Sugimoto
  • 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: 20080318144
    Abstract: To provide a toner including: a toner material that contains at least a binder resin, a pigment, and a pigment dispersant, wherein the pigment dispersant has an acid value of 20 mgKOH/g to 50 mgKOH/g and an amine value of 1 mgKOH/g to 50 mgKOH/g, and wherein the pigment contains at least aluminum phthalocyanine.
    Type: Application
    Filed: June 20, 2008
    Publication date: December 25, 2008
    Inventors: Naohiro Watanabe, Shinichi Wakamatsu, Hiroshi Yamashita, Tsuyoshi Sugimoto
  • 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
  • Patent number: 7435521
    Abstract: A toner for developing an electrostatic image which has a small particle size essential for attaining a high-quality image, and can output a high-quality image excellent in frictional charging property and free from scumming. The toner for developing an electrostatic image has the volume average particle diameter of 2.0 ?m to 7.1 ?m and the surface condition of the toner is in scab form.
    Type: Grant
    Filed: December 28, 2004
    Date of Patent: October 14, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinichiro Yagi, Hiroshi Yamada, Hiroshi Yamashita, Naohiro Watanabe, Tsunemi Sugiyama, Shigeru Emoto, Masami Tomita, Toshiki Nanya, Tadao Takikawa
  • Publication number: 20080233495
    Abstract: A toner producing method is provided, which comprises preparing toner base particles in an aqueous medium, wherein the toner base particles comprise resin fine particles, and forming a coating layer on the surface of the toner base particles, wherein the coating layer is formed by attaching or coating a toner functional substance onto the surface of the toner base particles using at least one of supercritical fluids and sub-supercritical fluids.
    Type: Application
    Filed: November 13, 2007
    Publication date: September 25, 2008
    Inventors: Masayuki Ishii, Chiaki Tanaka, Naohiro Watanabe, Kei Naitoh, Takuya Saito
  • Publication number: 20080233505
    Abstract: A toner, including a parent particulate material including a colorant and a binder resin, and an external additive including particles having an average primary particle diameter from 80 to less than 150 nm in an amount of from 0.03 to 2% by number, particles having an average primary particle diameter from 5 nm to less than 15 nm in an amount of from 50 to 95% by number, and particles having an average primary particle diameter from 15 to less than 40 nm in an amount of from 5 to 40% by number, and the particles having an average primary particle diameter from 80 to less than 150 nm include particles having an average primary particle diameter not less than 200 nm in an amount of from 10 to 30% by number, and have a weight reduction rate not greater than 3.00% when heated from 30 to 250° C.
    Type: Application
    Filed: March 11, 2008
    Publication date: September 25, 2008
    Inventors: Tsuneyasu NAGATOMO, Naohiro Watanabe, Osamu Uchinokura, Satoshi Kojima