Patents by Inventor Junichi Awamura

Junichi Awamura 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: 8017292
    Abstract: To provide a toner produced by emulsifying or dispersing in an aqueous medium particles containing at least polyester resin particles and by aggregating the polyester resin particles, wherein the polyester resin particles contain a polyester resin, the polyester resin is produced by condensation polymerization of an alcohol component containing 65 mol % or more 1,2-propanediol in a dihydroxy alcohol component and a carboxylic acid component containing purified rosin, and the softening point of the polyester resin is 80° C. or more and less than 120° C., and wherein the toner comprises a colorant and a releasing agent.
    Type: Grant
    Filed: April 30, 2008
    Date of Patent: September 13, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Akiyoshi Sabu, Akihiro Kotsugai, Shinya Nakayama, Hiroshi Yamashita, Tsuyoshi Sugimoto, Hiroshi Yamada, Junichi Awamura
  • Publication number: 20110200929
    Abstract: The present invention provides an electrostatic image developing toner capable of improving the dispersibility of wax in the toner and superior in offset resistance and in storageability (heat-resistant storageability) at high temperatures, and a two-component developer which uses this electrostatic image developing toner. The electrostatic image developing toner includes: a binder resin, a colorant, and a release agent, wherein the binder resin contains a polyester resin, and a block copolymer which has a polyolefin backbone unit.
    Type: Application
    Filed: October 23, 2009
    Publication date: August 18, 2011
    Inventors: Toshihiko Karato, Masahide Yamada, Junichi Awamura, Tomomi Suzuki
  • Publication number: 20110129773
    Abstract: A toner including a binder resin comprising a modified polyester having an ester bond and a chemical bond other than the ester bond, and a crystalline polyester; and a release agent comprising a microcrystalline wax comprising a hydrocarbon having 20 to 80 carbon atoms which comprises 55 to 70% by weight of a linear hydrocarbon. The microcrystalline wax has an acid value of from 0.1 to 20 mgKOH/g and a melting point of from 65 to 90° C. The melting point is a temperature at which a local maximum endothermic peak is observed in a differential thermal curve measured by differential scanning calorimetry (DSC). The release agent is dispersed in the toner with a dispersion diameter of from 0.06 to 1.50 ?m.
    Type: Application
    Filed: November 3, 2010
    Publication date: June 2, 2011
    Inventors: Hyo SHU, Fumihiro Sasaki, Hiroshi Yamashita, Masaki Watanabe, Junichi Awamura, Tsuyoshi Sugimoto, Teruki Kusahara, Satoshi Ogawa, Ryota Inoue, Daisuke Inoue
  • Patent number: 7943280
    Abstract: A toner containing a colorant, a binder resin and a laminar inorganic mineral in which part or all of the ions present between layers are modified by organic ions. The toner can be prepared by a method including dispersing or emulsifying a toner constituent mixture liquid containing the colorant, the binder resin and/or a precursor thereof, and the laminar inorganic mineral, in an aqueous medium. The density of the laminar inorganic mineral measured by XPS for the toner surface before (A) and after (B) mixing and kneading satisfies the following relationship: A>B.
    Type: Grant
    Filed: March 14, 2007
    Date of Patent: May 17, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Osamu Uchinokura, Naohiro Watanabe, Junichi Awamura
  • 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: 20110076607
    Abstract: A toner including at least one polyester resin serving as a binder resin, a colorant, a releasing agent, and a fixing aid, wherein the fixing aid includes a fatty acid amide-based compound, and the fatty acid amide-based compound is at least one of a fatty acid amide compound having a mono- or higher valent amide bond and a fatty acid amide-based compound having a mono- or higher valent amino group or a hydroxyl group.
    Type: Application
    Filed: May 22, 2009
    Publication date: March 31, 2011
    Inventors: Tsuyoshi Sugimoto, Hiroshi Yamashita, Naohiro Watanabe, Shinichi Wakamatsu, Masaki Watanabe, Satoshi Ogawa, Masana Shiba, Junichi Awamura, Naohito Shimota
  • Publication number: 20110076612
    Abstract: A method for producing a toner, containing: dispersing, in an aqueous medium, an oil phase which contains an organic solvent, and a binder resin component contained in the organic solvent, where the binder resin component contains a crystalline polyester resin and an amorphous polyester resin; and removing the organic solvent from the dispersion to obtain the toner, in which the dispersing further contains heating and dissolving the crystalline polyester and the amorphous polyester in the organic solvent to obtain a solution, cooling the solution so as to recrystallize the crystalline polyester resin, and mechanically pulverizing the recrystallized crystalline polyester resin so as to obtain a crystalline polyester dispersion.
    Type: Application
    Filed: September 27, 2010
    Publication date: March 31, 2011
    Inventors: Junichi AWAMURA, Hiroshi Yamashita, Teruki Kusahara, Tsuyoshi Sugimoto, Tomomi Suzuki
  • Publication number: 20110076610
    Abstract: A method of manufacturing toner including melting, mixing, and kneading a releasing agent and a coloring agent with at least part of a polyester binder resin, and suspending and granulating an oil phase comprising the binder resin, the coloring agent, and the releasing agent in an aqueous medium.
    Type: Application
    Filed: September 24, 2010
    Publication date: March 31, 2011
    Inventors: Satoshi Ogawa, Tsuyoshi Sugimoto, Naohito Shimota, Hiroshi Yamashita, Masana Shiba, Junichi Awamura
  • Publication number: 20100310980
    Abstract: A toner, including a colorant; a binder resin; a release agent; and a fixing supplemental component, wherein the toner has a storage elastic modulus G? (Pa) satisfying the following conditions: 5.0×104<G?<5.0×105 at 80° C. 1.0×104<G?<1.0×105 at 90° C. 5.0×103<G?<5.0×104 at 100° C. 1.0×103<G?<1.0×104 at 120° C. 1.0×103<G?<1.0×104 at 150° C.
    Type: Application
    Filed: May 11, 2010
    Publication date: December 9, 2010
    Inventors: Tsuyoshi Sugimoto, Naohito Shimota, Hiroshi Yamashita, Satoshi Ogawa, Masana Shiba, Junichi Awamura, Tsuneyasu Nagatomo, Masaki Watanabe
  • 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: 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: 7799498
    Abstract: The present invention provides an image forming apparatus capable of stably producing high quality images with time, without causing missing a central part of a thin line, however, with keeping an appropriate flowability of a toner. The toner used in the image forming apparatus is a toner which contains a binder resin, a colorant, and a laminar inorganic mineral in which at least part of an ion in layers is modified with an organic ion, the toner is granulated in an aqueous system, the volume average particle diameter Dv of the toner is in the range of 3.0 ?m<Dv<6.5 ?m, the aspect ratio of the toner is 0.81 to 0.89, and the surface of the toner is externally added with a plurality of types of fine particles.
    Type: Grant
    Filed: February 6, 2008
    Date of Patent: September 21, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Takuya Seshita, Junichi Awamura, Tomomi Suzuki, Toyoshi Sawada, Masahide Yamada
  • Publication number: 20100233609
    Abstract: The present invention relates to toner compositions containing: toner particles made of: binder resin; colorant; and a wax which is dispersed in the toner particles, where the toner composition satisfies relationship (2): B?394?400A? when 0.950<A??0.965 (2) where A? represents an average circularity of the toner composition, B represents a content of toner particles having a particle diameter not greater than 3 ?m expressed in % by number, and a concentration of the wax at a surface of the toner particles is larger than a concentration thereof in the center of the toner particles.
    Type: Application
    Filed: April 7, 2010
    Publication date: September 16, 2010
    Inventors: Hiroto HIGUCHI, Fumihiro Sasaki, Shinichiro Yagi, Shigeru Emoto, Junichi Awamura, Naohito Shimota, Masami Tomita, Toshiki Nanya, Takahiro Honda, Maiko Kondo
  • Publication number: 20100209838
    Abstract: A toner including a binder resin, a coloring agent, and a releasing agent, the toner formed by dispersing a toner liquid material which is prepared by dispersing the binder resin, the prepolymer, an elongation agent and/or a cross-linking agent for the prepolymer, the coloring agent, and the releasing agent in an organic solvent, dispersing the toner liquid material in an aqueous medium to obtain a liquid dispersion in at least one of cross linking reaction and elongation reaction, and removing the organic solvent from the liquid dispersion, and the toner satisfying the following relationship: 1.35< or =M(g)/M(p)< or =1.90, where M(g) represents the content of the gel composition formed in the at least one of cross linking reaction and elongation reaction and M(P) represents the content of the prepolymer in the toner liquid material when the total of M(P) and the content of the binder resin in the toner liquid material is set to be 100 g.
    Type: Application
    Filed: February 19, 2010
    Publication date: August 19, 2010
    Inventors: Teruki KUSAHARA, Junichi AWAMURA, Tomomi SUZUKI, Toshihiko KARATO
  • Patent number: 7736826
    Abstract: A toner composition including toner particles including at least a binder resin; and a colorant, wherein the toner composition satisfies at least one of the following relationships (1) and (2): B?14 when 155<A?180; and B?0.6A?79 when 145?A?155,??(1) wherein A represents a shape factor SF-1 of the toner composition and B represents a content of toner particles having a particle diameter not greater than 3 ?m; and B?14 when 0.920?A??0.950; and B?394?400A? when 0.950<A??0.965??(2) wherein A? represents an average circularity of the toner composition and B represents a content of toner particles having a particle diameter not greater than 3 ?m.
    Type: Grant
    Filed: September 17, 2008
    Date of Patent: June 15, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroto Higuchi, Fumihiro Sasaki, Shinichiro Yagi, Shigeru Emoto, Junichi Awamura, Naohito Shimota, Masami Tomita, Toshiki Nanya, Takahiro Honda, Maiko Kondo
  • Patent number: 7702271
    Abstract: An image forming apparatus including an image bearing member; a charger; a light irradiator; a developing device; a transfer device; an image bearing member's cleaner; and a fixing device, wherein the fixing device includes a fixing member configured to fix a toner image upon application of heat and pressure thereto; a pressing member configured to press the recording material toward the fixing member; and a cleaning member configured to clean a surface of the fixing member and/or the pressing member, wherein the cleaning member has an outermost layer including a reactive material which increases viscoelasticity of a binder resin of the toner by reacting with the binder resin.
    Type: Grant
    Filed: September 4, 2008
    Date of Patent: April 20, 2010
    Assignee: Ricoh Company Limited
    Inventors: Hiroshi Yamada, Fumihiro Sasaki, Shigeru Emoto, Jun Okamoto, Shinji Ohtani, Hiroto Higuchi, Naohito Shimota, Shinichiro Yagi, Junichi Awamura, Tomomi Suzuki, Masami Tomita, Toshiki Nanya, Yoshiki Yamaguchi
  • 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
  • Publication number: 20100062352
    Abstract: The present invention provides a method for producing a toner, the method including: preparing a wax dispersion liquid by cooling a wax solution, in which a wax is heated and dissolved or dispersed in an organic solvent, in a container so that a standard deviation ? of a temperature distribution between a center portion of the container and an inner wall of the container is 0.5 or less and the cooling rate is 2.0° C./min or more, to precipitate wax particles in the wax solution; forming toner base precursor particles by adding an aqueous phase containing resin fine particles into an oil phase containing at least the wax dispersion liquid, a colorant and a binder resin and mixing the oil phase and the aqueous phase with each other; and preparing toner base particles by removing the solvent from the toner base precursor particles.
    Type: Application
    Filed: September 8, 2009
    Publication date: March 11, 2010
    Inventors: Teruki Kusahara, Junichi Awamura, Tomomi Suzuki, Toshihiko Karato
  • 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