Patents by Inventor Kohki Katoh

Kohki Katoh 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: 20080244733
    Abstract: An information management system includes a management terminal, and a production base terminal, an installation terminal, a recycling base terminal or a reproduction base terminal connected to the management terminal via a network. Upon receipt of product information and recording medium information from the production base terminal and the customer information from the installation base terminal, the management terminal stores therein the information, and selects a recycling base or a reproduction base based on the information. The management terminal transmits at least one of the product information and the recording medium information to the recycling base terminal or the reproduction base terminal.
    Type: Application
    Filed: March 14, 2008
    Publication date: October 2, 2008
    Inventors: Kohki Katoh, Haruhiro Tohda, Morio Takahashi, Fumio Itoku, Fujio Satoh
  • Patent number: 7346287
    Abstract: A transfer device transfers a visual image from an image carrier to a recording medium. The transfer device includes a first transfer element that moves and receives the visual image from the image carrier on a first surface of the first transfer element, a second transfer element provided opposite to the first surface of the first transfer element to pinch and convey the recording medium through a secondary transfer nip part, a facing roller provided on a second surface of the first transfer element opposite to the first surface thereof, and a constant-current power supply that applies an electric current voltage to a core metal of the facing roller to transfer the visual image from the first transfer element to the recording medium. The electric current voltage applied to the core metal has a polarity equal to a polarity of the visual image and is subjected to a constant-current control.
    Type: Grant
    Filed: February 13, 2006
    Date of Patent: March 18, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiromi Ogiyama, Kohki Katoh, Akihiro Sugino, Mitsuru Takahashi, Katsuya Kawagoe, Yuuji Sawai
  • Patent number: 7122286
    Abstract: A toner for developing a latent electrostatic image to a toner image, including a binder resin, and a magnetic material which is blackened by coating the surface of a magnetic powder with a coloring agent, the magnetic material being in an amount of 10 wt.% to 40 wt.% of the entire weight of the toner, a method of forming an image, using a two-component developer containing the toner, an image formation apparatus using the two-component developer, and a toner container containing therein the toner, and an image formation apparatus equipped with the toner container are proposed.
    Type: Grant
    Filed: April 5, 2001
    Date of Patent: October 17, 2006
    Assignee: Ricoh Company, Ltd.
    Inventors: Masanori Suzuki, Yohichiroh Watanabe, Masahide Yamashita, Kazuhito Watanabe, Keiko Shiraishi, Kohki Katoh
  • Publication number: 20060127116
    Abstract: A transfer device transfers a visual image from an image carrier to a recording medium. The transfer device includes a first transfer element that moves and receives the visual image from the image carrier on a first surface of the first transfer element, a second transfer element provided opposite to the first surface of the first transfer element to pinch and convey the recording medium through a secondary transfer nip part, a facing roller provided on a second surface of the first transfer element opposite to the first surface thereof, and a constant-current power supply that applies an electric current voltage to a core metal of the facing roller to transfer the visual image from the first transfer element to the recording medium. The electric current voltage applied to the core metal has a polarity equal to a polarity of the visual image and is subjected to a constant-current control.
    Type: Application
    Filed: February 13, 2006
    Publication date: June 15, 2006
    Inventors: Hiromi Ogiyama, Kohki Katoh, Akihiro Sugino, Mitsuru Takahashi, Katsuya Kawagoe, Yuuji Sawai
  • Patent number: 7052815
    Abstract: A color toner including toner particles including a colorant, a binder resin, and a wax; and an external additive including at least one of an inorganic particulate material and a particulate resin, wherein the binder resin includes a polyester resin (A) having a crystallinity and a formula (—O—CO—CR1=CR2-CO—O—(CH2)n—)m, wherein R1 and R2 independently represents a hydrocarbon, and n and m are repeating numbers; a resin (B); and a resin (C), wherein the resins (B) and (C) and the wax have an island-sea structure such that the resin (C) is present like islands in a sea of the resin (B) and the wax is substantially included in the resin (C). A toner container, an image forming method, an image forming apparatus and a process cartridge including the color toner are also provided.
    Type: Grant
    Filed: May 23, 2003
    Date of Patent: May 30, 2006
    Assignee: Ricoh Company, Limited
    Inventors: Toyoshi Sawada, Masanori Suzuki, Kohki Katoh, Yohichiroh Watanabe, Keiko Shiraishi, Takuya Saito, Masashi Nagayama
  • Patent number: 7049037
    Abstract: A color toner composition including at least toner particles including at least a binder resin; a colorant and a release agent dispersed in the binder resin; and a titania as an external additive, wherein the colorant has an average dispersion particle diameter not greater than 0.5 ?m; the release agent and the binder resin are insoluble to each other; the toner particles satisfy the relationship: 0.05?Dw/D4?0.4, wherein Dw represents an average dispersion particle diameter of the release agent and D4 represents a weight-average particle diameter of the toner particles; and the titania has a segregation rate of from 0.5 to 5%.
    Type: Grant
    Filed: August 6, 2004
    Date of Patent: May 23, 2006
    Assignee: Ricoh Company, Ltd.
    Inventors: Kohki Katoh, Masanori Suzuki, Yohichiro Watanabe, Masahide Yamashita, Akihiro Kotsugai, Toyoshi Sawada, Keiko Shiraishi
  • Publication number: 20050277046
    Abstract: A color toner including toner particles including a colorant, a binder resin, and a wax; and an external additive including at least one of an inorganic particulate material and a particulate resin, wherein the binder resin includes a polyester resin (A) having a crystallinity and a formula (—O—CO—CR1?CR2—CO—O—(CH2)n—)m, wherein R1 and R2 independently represents a hydrocarbon, and n and m are repeating numbers; a resin (B); and a resin (C), wherein the resins (B) and (C) and the wax have an island-sea structure such that the resin (C) is present like islands in a sea of the resin (B) and the wax is substantially included in the resin (C). A toner container, an image forming method, an image forming apparatus and a process cartridge including the color toner are also provided.
    Type: Application
    Filed: August 4, 2005
    Publication date: December 15, 2005
    Inventors: Toyoshi Sawada, Masanori Suzuki, Kohki Katoh, Yohichiroh Watanabe, Keiko Shiraishi, Takuya Saito, Masashi Nagayama
  • Patent number: 6916587
    Abstract: A toner including at least a binder resin; a colorant; and a charge controlling agent, in which the binder resin includes at least a polyester resin having a molecular weight distribution such that components having a molecular weight not greater than 500 are included in an amount of 4% by weight and at least a peak is present in a range of from 3,000 to 9,000 when measured by Gel Permeation Chromatography. In addition, the binder resin does not include a tetrahydrofuran-insoluble compound and the charge controlling agent is a resin charge controlling agent including at least units obtained from a monomer including a sulfonate group; an aromatic monomer including an electron absorption group; and an acrylic ester and/or a methacrylic ester monomer.
    Type: Grant
    Filed: April 3, 2002
    Date of Patent: July 12, 2005
    Assignee: Ricoh Company Limited
    Inventors: Hiroyuki Fushimi, Toshiki Nanya, Osamu Uchinokura, Shinichiro Yagi, Kohki Katoh
  • Patent number: 6858365
    Abstract: A toner, a developing method and apparatus is provided to satisfy both the low temperature fixation property and the hot offset property and that has a wide range of fixing temperature. The toner for an image formation comprises at least metal materials in a binding resin, wherein the toner is measured by a stand-alone type flow tester, and has a softening temperature of 65˜77.5° C., a flow beginning temperature of 100˜120° C., a melt temperature by a ½ method is 145˜195° C., and an average length of a short axis of a primary particle of the metal materials is 0.01˜0.4 ?m.
    Type: Grant
    Filed: March 22, 2002
    Date of Patent: February 22, 2005
    Assignee: Ricoh Company, Ltd.
    Inventors: Toyoshi Sawada, Masanori Suzuki, Kohki Katoh, Yohichiroh Watanabe, Keiko Shiraishi, Takuya Saito
  • Patent number: 6852459
    Abstract: A color toner composition including at least toner particles including at least a binder resin; a colorant and a release agent dispersed in the binder resin; and a titania as an external additive, wherein the colorant has an average dispersion particle diameter not greater than 0.5 ?m; the release agent and the binder resin are insoluble to each other; the toner particles satisfy the relationship: 0.05?Dw/D4?0.4, wherein Dw represents an average dispersion particle diameter of the release agent and D4 represents a weight-average particle diameter of the toner particles; and the titania has a segregation rate of from 0.5 to 5%.
    Type: Grant
    Filed: February 22, 2002
    Date of Patent: February 8, 2005
    Assignee: Ricoh Company, Ltd.
    Inventors: Kohki Katoh, Masanori Suzuki, Yohichiro Watanabe, Masahide Yamashita, Akihiro Kotsugai, Toyoshi Sawada, Keiko Shiraishi
  • Publication number: 20050008962
    Abstract: A color toner composition including at least toner particles including at least a binder resin; a colorant and a release agent dispersed in the binder resin; and a titania as an external additive, wherein the colorant has an average dispersion particle diameter not greater than 0.5 ?m; the release agent and the binder resin are insoluble to each other; the toner particles satisfy the relationship: 0.05?Dw/D4? 0.4, wherein Dw represents an average dispersion particle diameter of the release agent and D4 represents a weight-average particle diameter of the toner particles; and the titania has a segregation rate of from 0.5 to 5%.
    Type: Application
    Filed: August 6, 2004
    Publication date: January 13, 2005
    Inventors: Kohki Katoh, Masanori Suzuki, Yohichiro Watanabe, Masahide Yamashita, Akihiro Kotsugai, Toyoshi Sawada, Keiko Shiraishi
  • Patent number: 6829450
    Abstract: In an electrophotographic image forming apparatus of the type including a plurality of image carriers arranged along an image transfer belt and an image transferring device configured to transfer toner images of different colors from the image carriers to a sheet being conveyed by an image transfer belt or by way of the image transfer belt by applying a bias to the belt, a bias applying method of the present invention can measure a current leaking between a plurality of high-tension power supply sections or to the ends thereof as AC resistances between respective terminals and therefore to accurately measure the leak currents of DC components. Therefore, when relatively high DC components are selected, a difference in current between a plurality of power supply sections can be maintained constant.
    Type: Grant
    Filed: July 9, 2003
    Date of Patent: December 7, 2004
    Assignee: Ricoh Company, Ltd.
    Inventors: Takahiro Tamiya, Akihiro Sugino, Hiromi Ogiyama, Katsuya Kawagoe, Kohki Katoh, Mitsuru Takahashi, Yuuji Sawai
  • Patent number: 6818370
    Abstract: A toner for developing an electrostatic latent image, containing a colorant and a binder resin composed of two different resins (A) and (B), wherein resin (A) is substantially free of tetrahydrofuran insolubles, is selected from polyester resins and polyol resins and has such a molecular weight distribution according to gel permeation chromatography that (a) a main peak is present in a molecular weight of 3000 to 9,000 and (b) that portion of resin (A) having a molecular weight of 500 or less accounts for 4% or less based on a total weight of resin (A), wherein resin (B) is substantially free of tetrahydrofuran insolubles and is a polyester resin containing a diol component represented by the formula (1): and wherein the weight ratio of resin (A) to resin (B) is in the range of 60:40 to 85:15.
    Type: Grant
    Filed: November 27, 2002
    Date of Patent: November 16, 2004
    Assignee: Ricoh Company, Ltd.
    Inventors: Osamu Uchinokura, Hiroyuki Fushimi, Kohki Katoh, Shinichiro Yagi, Toshiki Nanya
  • Patent number: 6785500
    Abstract: An image forming apparatus of the present invention includes a cleaning device for cleaning an intermediate image transfer body. A cleaning blade included in the image transfer body is formed of fluorocarbon resin or a thin layer of fluorocarbon resin is formed on the surface of the intermediate image transfer body. Further, wax is coated on the intermediate image transfer body or wax or lubricant powder is contained in toner. A moving mechanism holds the cleaning blade spaced from the intermediate image transfer body at least when image formation is not under way.
    Type: Grant
    Filed: July 12, 2002
    Date of Patent: August 31, 2004
    Assignee: Ricoh Company, Ltd.
    Inventors: Mitsuru Takahashi, Yuuji Sawai, Hiromi Ogiyama, Katsuya Kawagoe, Akihiro Sugino, Kohki Katoh
  • Publication number: 20040105692
    Abstract: In an electrophotographic image forming apparatus of the type including a plurality of image carriers arranged along an image transfer belt and an image transferring device configured to transfer toner images of different colors from the image carriers to a sheet being conveyed by an image transfer belt or by way of the image transfer belt by applying a bias to the belt, a bias applying method of the present invention can measure a current leaking between a plurality of high-tension power supply sections or to the ends thereof as AC resistances between respective terminals and therefore to accurately measure the leak currents of DC components. Therefore, when relatively high DC components are selected, a difference in current between a plurality of power supply sections can be maintained constant.
    Type: Application
    Filed: July 9, 2003
    Publication date: June 3, 2004
    Inventors: Takahiro Tamiya, Akihiro Sugino, Hiromi Ogiyama, Katsuya Kawagoe, Kohki Katoh, Mitsuru Takahashi, Yuuji Sawai
  • Patent number: 6741821
    Abstract: An image forming apparatus comprises a latent image support which supports an electrostatic latent image. A charging unit charges a surface of the image support. A latent image formation unit forms an electrostatic latent image on the image support surface. A developing unit develops the latent image with toner to form a toner image. A transfer unit transfers the toner image from the image support to a recording medium. A transport unit transports the recording medium so that the image support surface is countered to a surface of the recording medium. The surface of the image support has a coefficient of friction ranging from 0.1 to 0.7 according to Euler belt method, and a difference between a speed of the image support and a speed of the recording medium is below 1%, and the image support has an outermost surface containing a filler and a binder resin.
    Type: Grant
    Filed: June 25, 2002
    Date of Patent: May 25, 2004
    Assignee: Ricoh Company, Ltd.
    Inventors: Akihiro Sugino, Yuuji Sawai, Mitsuru Takahashi, Kohki Katoh, Katsuya Kawagoe, Hiromi Ogiyama, Takahiro Tamiya
  • Patent number: 6740461
    Abstract: A carrier is composed of carrier particles, each carrier particle having a core particle containing at least a magnetic material and a surface coating layer provided on the core particle containing at least a resin, the surface coating layer being constituted of a plurality of regions, the regions being separately formed and joined together to form a complex configuration, and having different phase lags when the surface coating layer is subjected to scanning by phase imaging measurement using a scanning probe microscope in a tapping mode, wherein a region having a phase lag over the average phase lag obtained from Eavg=&Sgr;(E(i)·S(i))/&Sgr;S(i) has an area SO, and SO and &Sgr;S(i) are in a relationship of 10%≦SO/&Sgr;S(i)×100≦90% when each region comprises a component A(i) having an area S(i) and a phase lag E(i), in which i represents the number of regions with different phase lags. A two-component developer employs the above-mentioned carrier.
    Type: Grant
    Filed: December 20, 2002
    Date of Patent: May 25, 2004
    Assignee: Ricoh Company, Ltd.
    Inventors: Masahide Yamashita, Masanori Suzuki, Yohichiroh Watanabe, Kazuhito Watanabe, Keiko Shiraishi, Kohki Katoh
  • Patent number: 6733939
    Abstract: The electrophotographic toner according to the present invention comprises a binder resin, a colorant, and a negative charge control agent. The binder resin is polyester and/or polyol. The negative charge control agent comprises components which are (1) sulfonic-acid containing monomers, (2) aromatic monomers having electron-withdrawing groups, and (3) acrylate monomers and/or methacrylate monomers. In particular, substituted phenyl maleimides and substituted phenyl itaconimides are prefereably used as the aromatic monomers. Moreover, n-butyl (meth)acrylates and 2-ethylhexyl (meth)acrylates are prefereably used as the acrylate monomers and/or methacrylate monomers.
    Type: Grant
    Filed: September 28, 2001
    Date of Patent: May 11, 2004
    Assignee: Ricoh Company, Ltd.
    Inventors: Toshiki Nanya, Hiroyuki Fushimi, Osamu Uchinokura, Shinichiro Yagi, Kohki Katoh
  • Patent number: 6716561
    Abstract: A toner for developing electrostatic latent images, including a matrix of a first resin selected from polyester resins, polyol resins and mixtures thereof, a plurality of domains of a second resin dispersed in the matrix and containing a wax. The amount of the wax is 2-15% by weight based on the weight of the toner The matrix is substantially free of domains of the second resin having a maximum diameter of greater than 2.0 &mgr;m. A part of the domains containing the wax having a maximum diameter of at least 0.2 &mgr;m constitutes a part of an outer surface of the toner.
    Type: Grant
    Filed: November 27, 2001
    Date of Patent: April 6, 2004
    Assignee: Ricoh Company, Ltd.
    Inventors: Keiko Shiraishi, Masanori Suzuki, Yohichiroh Watanabe, Masahide Yamashita, Akihiro Kotsugai, Toyoshi Sawada, Kohki Katoh
  • Publication number: 20030219670
    Abstract: A color toner including toner particles including a colorant, a binder resin, and a wax; and an external additive including at least one of an inorganic particulate material and a particulate resin, wherein the binder resin includes a polyester resin (A) having a crystallinity and a formula (—O—CO—CR1═CR2—CO—O—(CH2)n—)m, wherein R1 and R2 independently represents a hydrocarbon, and n and m are repeating numbers; a resin (B); and a resin (C), wherein the resins (B) and (C) and the wax have an island-sea structure such that the resin (C) is present like islands in a sea of the resin (B) and the wax is substantially included in the resin (C). A toner container, an image forming method, an image forming apparatus and a process cartridge including the color toner are also provided.
    Type: Application
    Filed: May 23, 2003
    Publication date: November 27, 2003
    Inventors: Toyoshi Sawada, Masanori Suzuki, Kohki Katoh, Yohichiroh Watanabe, Keiko Shiraishi, Takuya Saito, Masashi Nagayama