Patents by Inventor Tsuneyasu Nagatomo

Tsuneyasu Nagatomo 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: 20130244158
    Abstract: A toner set, including: a transparent toner including a binder resin a, a releasing agent a and no colorant; and one or more color toners, each including a binder resin b, a colorant b and a releasing agent b, wherein the binder resin a includes a non-crystalline resin ? and a crystalline resin ?, the binder resin b includes a non-crystalline resin ? and a crystalline resin ?, the releasing agent a has an average particle diameter as a long diameter of 0.2 ?m to 2.0 ?m, and there is a relationship of 1<A/B<1.5, where A is an area of the releasing agent a in a transparent toner cross-section from a surface thereof to a ?-depth of a volume-average particle diameter, and B is an area of the releasing agent b in a color-toner cross-section from a surface thereof to a ?-depth of a volume-average particle diameter.
    Type: Application
    Filed: March 13, 2013
    Publication date: September 19, 2013
    Inventors: Junichi AWAMURA, Teruki Kusahara, Satoshi Ogawa, Daisuke Ito, Daisuke Inoue, Osamu Uchinokura, Satoshi Kojima, Tsuneyasu Nagatomo, Mamoru Hozumi, Syouko Satoh
  • Publication number: 20130244156
    Abstract: A toner for developing an electrostatic image, including: toner base particles each including a binder resin and a releasing agent; and inorganic fine particles, wherein the toner includes the inorganic fine particles as an external additive on a surface of the toner base particle, wherein the toner base particles have a BET specific surface area of 2.5 m2/g to 5.0 m2/g, and wherein the inorganic fine particles comprise inorganic fine particles (A) which are each a secondary particle where a plurality of primary particles are coalesced together.
    Type: Application
    Filed: March 11, 2013
    Publication date: September 19, 2013
    Inventors: Satoshi KOJIMA, Tsuneyasu Nagatomo, Syouko Satoh, Osamu Uchinokura, Junichi Awamura, Satoshi Ogawa, Takahiro Honda, Daisuke Ito, Teruki Kusahara, Masaki Watanabe, Daisuke Inoue, Kiwako Hirohara
  • Publication number: 20130243488
    Abstract: A toner including: toner base particles; and external additive, the toner base particles each comprising binder resin and colorant, wherein the external additive comprises coalesced particles, the coalesced particles are each a non-spherical secondary particle in which primary particles are coalesced together, and an index of a particle size distribution of the coalesced particles is expressed by Formula (1): Db 50 Db 10 ? 1.
    Type: Application
    Filed: March 8, 2013
    Publication date: September 19, 2013
    Inventors: Satoshi KOJIMA, Tsuneyasu NAGATOMO, Syouko SATOH, Osamu UCHINOKURA, Junichi AWAMURA, Satoshi OGAWA, Takahiro HONDA, Daisuke ITO, Teruki KUSAHARA, Masaki WATANABE, Daisuke INOUE
  • Publication number: 20130244155
    Abstract: A toner including: toner base particles; and an external additive, the toner base particles each comprising a binder resin and a colorant, wherein the external additive comprises non-spherical particles and spherical particles, wherein the non-spherical particles are each a secondary particle in which spherical primary particles are coalesced together, and wherein the non-spherical particles and the spherical particles in the external additive satisfy a relationship expressed by the following formula (1): 3Ca(%)<Cb(%)??Formula (1) where Ca is greater than 10% but smaller than 20% and Cb is greater than 40% but smaller than 70%, and Ca and Cb are values given by: Ca = ( an ? ? amount ? ? of ? ? the ? ? non ? - ? spherical ? ? particles ? ? ( % ? ? by ? ? mass ) / 100 ) × ( a ? ? projected ? ? area ? ? of ? ? the ? ? non ? - ? spherical ? ? particles ? ? ( cm 2 ? / ? g ) ) ( an ? ? amount ? ? of ?
    Type: Application
    Filed: March 8, 2013
    Publication date: September 19, 2013
    Inventors: Syouko Satoh, Tsuneyasu Nagatomo, Satoshi Kojima, Osamu Uchinokura, Junichi Awamura, Daisuke Ito, Satoshi Ogawa, Kiwako Hirohara, Takahiro Honda, Daisuke Inoue
  • Publication number: 20130224648
    Abstract: Electrostatic image developing toner particles including: a crystalline polyester resin; a non-crystalline polyester resin; a releasing agent; and a colorant, wherein the electrostatic image developing toner particles have a glass transition temperature of 40° C. to 60° C. where the glass transition temperature is measured with a differential scanning calorimeter (DSC), and wherein the electrostatic image developing toner particles have an adhesive force between the toner particles of 1.4 mN to 2.2 mN where the adhesive force between the toner particles is measured after the electrostatic image developing toner particles have been stored at 50° C.
    Type: Application
    Filed: November 9, 2011
    Publication date: August 29, 2013
    Inventors: Takahiro Honda, Osamu Uchinokura, Junichi Awamura, Satoshi Ogawa, Satoshi Kojima, Teruki Kusahara, Daisuke Inoue, Daisuke Ito, Tsuneyasu Nagatomo, Masaki Watanabe
  • Publication number: 20130216944
    Abstract: A toner contains a binder resin, a colorant, and a releasing agent, wherein the toner contains toner particles, and wherein a proportion of the toner particles containing one or more voids having diameters D1 of larger than 0.0 ?m but 0.5 ?m or smaller is more than 5.0% to 60%, and a proportion of the toner particles containing one or more voids having diameters D2 of 1.0 ?m or larger is 10% or less.
    Type: Application
    Filed: October 18, 2011
    Publication date: August 22, 2013
    Inventors: Masana Shiba, Ryuta Chiba, Tsuneyasu Nagatomo
  • Publication number: 20130130171
    Abstract: A toner including a core particle, an inner shell layer covering the core, and an outer shell layer covering the inner shell layer is provided. The core particle includes a resin P. The inner shell layer includes fine particles of a resin A. The outer shell layer includes fine particles of a resin B. The toner satisfies the following formulae (1) to (3): 4.5?T½(P)?Tfb(P)?14??(1) 20?T½(A)?Tfb(A)?40??(2) 23.5?T½(B)?Tfb(B)?40??(3) wherein T½(P), T½(A), and T½(B) represent ½ method temperatures of the resins P, A, and B, respectively, and Tfb(P), Tfb(A), and Tfb(B) represent flow beginning temperatures of the resins P, A, and B, respectively, and wherein the ½ method temperatures and the flow beginning temperatures are measured by a flowtester.
    Type: Application
    Filed: November 1, 2012
    Publication date: May 23, 2013
    Inventors: Masaki Watanabe, Osamu Uchinokura, Junichi Awamura, Takahiro Honda, Satoshi Ogawa, Tsuneyasu Nagatomo, Hiroshi Yamashita
  • Patent number: 8435716
    Abstract: A method for producing a toner, including: dispersing toner particles containing at least a binder resin in a first aqueous medium so as to produce an aqueous dispersion; and subjecting the aqueous dispersion to heat treatment, wherein the electric conductivity of the aqueous dispersion after the heat treatment is higher than the electric conductivity of the aqueous dispersion before the heat treatment by 50 ?S/cm or less.
    Type: Grant
    Filed: February 4, 2011
    Date of Patent: May 7, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Masaki Watanabe, Osamu Uchinokura, Tsuneyasu Nagatomo, Takahiro Honda, Ryuta Chiba
  • Patent number: 8377620
    Abstract: An image forming method including charging an image bearing member by applying combination of DC voltage and AC voltage with frequency of 6.5 to 8.5 cycle/mm; irradiating the image bearing member with light to form an electrostatic image; developing the electrostatic image with a developer including toner to form a toner image; transferring the toner image onto a receiving material; fixing the toner image; cleaning the image bearing member with a blade; then applying a lubricant to the image bearing member; and then spreading the lubricant with a spreading member countering the image bearing member. The toner includes toner particles granulated in an aqueous medium; and at least three kinds of external additives including a first particulate hydrophobic silica, a particulate hydrophobic titanium oxide and a second particulate hydrophobic silica respectively having BET specific surface areas of 20 to 40 m2/g, 40 to 80 m2/g, and 130 to 300 m2/g.
    Type: Grant
    Filed: November 24, 2008
    Date of Patent: February 19, 2013
    Assignee: Ricoh Company, Limited
    Inventors: Tsuneyasu Nagatomo, Toyoshi Sawada, Satoshi Kojima
  • Patent number: 8293442
    Abstract: Disclosed is a resin particle having a volume average particle diameter of 10 nm to 500 nm, obtained by polymerizing an addition polymerizable monomer containing a silsesquioxane (a) represented by Formula (I) or by copolymerizing the silsesquioxane (a) with an addition polymerizable monomer (b), where R1 to R7 each independently represent a group selected from the group consisting of hydrogen, alkyl having 1 to 40 carbon atoms, substituted or unsubstituted aryl, and substituted or unsubstituted arylalkyl; any hydrogen in the alkyl group is optionally substituted by fluorine and any —CH2— is optionally substituted by —O—, —CH?CH—, cycloalkylene or cycloalkenylene; any hydrogen in alkylene in the arylalkyl group is optionally substituted by fluorine and any —CH2— is optionally substituted by —O— or —CH?CH—; and A1 represents an addition polymerizable functional group.
    Type: Grant
    Filed: September 22, 2009
    Date of Patent: October 23, 2012
    Assignees: Ricoh Company, Ltd., JNC Corporation
    Inventors: Masaki Watanabe, Naohito Shimota, Hiroshi Yamashita, Naohiro Watanabe, Tsuneyasu Nagatomo, Tsuyoshi Sugimoto, Shinichi Wakamatsu, Kenya Itoh, Mikio Yamahiro
  • Patent number: 8227164
    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: Grant
    Filed: May 11, 2010
    Date of Patent: July 24, 2012
    Assignee: Ricoh Company, Limited
    Inventors: Tsuyoshi Sugimoto, Naohito Shimota, Hiroshi Yamashita, Satoshi Ogawa, Masana Shiba, Junichi Awamura, Tsuneyasu Nagatomo, Masaki Watanabe
  • Patent number: 8178268
    Abstract: A magenta toner, produced by a method including suspending an oily liquid comprising a binder resin and a colorant in an aqueous medium, wherein the colorant comprises a naphthol pigment and a quinacridone pigment, and the quinacridone pigment comprises a pigment having a specific formula.
    Type: Grant
    Filed: September 28, 2009
    Date of Patent: May 15, 2012
    Assignee: Ricoh Company, Limited
    Inventors: Naohiro Watanabe, Shinichi Wakamatsu, Naohito Shimota, Hiroshi Yamashita, Tsuyoshi Sugimoto, Masaki Watanabe, Tsuneyasu Nagatomo
  • Publication number: 20120021347
    Abstract: To provide a toner A containing: base particles, each containing polyester, microcrystalline wax, and a colorant; and spherical silica particles having an average primary particle diameter of 100 nm to 150 nm, wherein the microcrystalline wax has an onset temperature of 45° C. to 60° C. as determined by DSC, and a carbon number distribution of 25 to 55.
    Type: Application
    Filed: July 22, 2011
    Publication date: January 26, 2012
    Inventors: Naohito Shimota, Takahiro Honda, Tsuneyasu Nagatomo, Ryuta Chiba
  • Publication number: 20110294058
    Abstract: A toner containing a wax, wherein the wax has a mass decrease at 165° C. of 10% by mass or less, a molecular chain consisting of C—H bonds and C—C bonds, and a penetration of 5 mm to 25 mm, wherein a product of a ½ method softening point (° C.) of the toner and an amount of the wax on a surface of the toner is 8 to 20, and wherein the toner is obtained by a method including emulsifying or dispersing in an aqueous medium a toner material liquid, which is a liquid containing a toner material, which contains the wax.
    Type: Application
    Filed: May 24, 2011
    Publication date: December 1, 2011
    Inventors: Masana SHIBA, Takahiro Honda, Tsuneyasu Nagatomo, Naohito Shimota, Ryuta Chiba
  • Patent number: 8043778
    Abstract: A toner including toner particles including a binder resin, and a modified layered inorganic material in which at least part of interlayer ions is replaced with an organic ion, and a fatty acid metal compound located on a surface of the toner particles; and an external additive located on the fatty acid metal compound, wherein the external additive is a material different from the fatty acid metal compound. An image forming apparatus including an image bearing member; a developing device configured to develop the electrostatic latent image with a developer including the toner; a transfer device; and a fixing device. A method for preparing the toner including dispersing or emulsifying a toner composition including a modified layered inorganic material to prepare toner particles; mixing a fatty acid metal compound with the toner particles; and second mixing the toner particles with an external additive.
    Type: Grant
    Filed: September 10, 2007
    Date of Patent: October 25, 2011
    Assignee: Ricoh Company Limited
    Inventors: Tsuneyasu Nagatomo, Naohiro Watanabe, Osamu Uchinokura, Satoshi Kojima
  • Patent number: 8029960
    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: Grant
    Filed: March 11, 2008
    Date of Patent: October 4, 2011
    Assignee: Ricoh Company Limited
    Inventors: Tsuneyasu Nagatomo, Naohiro Watanabe, Osamu Uchinokura, Satoshi Kojima
  • Publication number: 20110200928
    Abstract: A method for producing a toner, including: dispersing toner particles containing at least a binder resin in a first aqueous medium so as to produce an aqueous dispersion; and subjecting the aqueous dispersion to heat treatment, wherein the electric conductivity of the aqueous dispersion after the heat treatment is higher than the electric conductivity of the aqueous dispersion before the heat treatment by 50 ?S/cm or less.
    Type: Application
    Filed: February 4, 2011
    Publication date: August 18, 2011
    Inventors: Masaki WATANABE, Osamu Uchinokura, Tsuneyasu Nagatomo, Takahiro Honda, Ryuta Chiba
  • Publication number: 20110151372
    Abstract: A toner obtained by a toner production method which includes dissolving or dispersing in an organic solvent a toner material containing at least a calixarene derivative and a binder resin or a binder resin precursor, to thereby prepare a solution or dispersion liquid of the toner material, adding the solution or dispersion liquid to an aqueous medium for emulsification or dispersion, to thereby prepare an emulsion or dispersion liquid, and removing the organic solvent from the emulsion or dispersion liquid.
    Type: Application
    Filed: December 7, 2010
    Publication date: June 23, 2011
    Inventors: Masaki Watanabe, Hiroshi Yamashita, Naohiro Watanabe, Tsuneyasu Nagatomo
  • Publication number: 20110033794
    Abstract: A toner containing a binder, a colorant, and a wax having a molecular chain consisting of C—H bond and C—C bond, wherein the mass reduction of the wax at 165° C. is 10% by mass or less, and the total amount of the wax in the toner measured by a DSC method is 1% by mass to 8% by mass, wherein a ratio, Sbet/SF, of a BET specific surface area (Sbet) of the toner to an average circularity (SF) of the toner is 1.0 m2/g or more to less than 3.6 m2/g, wherein the toner is obtained through a process which contains at least emulsifying or dispersing a toner material liquid in an aqueous medium containing a surfactant, and wherein the toner material liquid is a liquid containing toner-forming materials which contains at least the binder, the colorant and the wax.
    Type: Application
    Filed: August 2, 2010
    Publication date: February 10, 2011
    Inventors: Naohiro WATANABE, Naohito SHIMOTA, Yasuaki IWAMOTO, Masana SHIBA, Satoshi KOJIMA, Masaki WATANABE, Tsuneyasu NAGATOMO, Hyo SHU
  • 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