Patents by Inventor Hirotaka Matsuoka

Hirotaka Matsuoka 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: 5999788
    Abstract: A fixing device comprises a heat fixing roller in which a heat resistant elastic layer is formed on a cylindrical metal core and, further, a heat resistant resin layer is coated on the surface thereof, an endless belt, a pressure member disposed in the inside of the endless belt, wherein the endless belt is wound around the heat fixing roller for a predetermined angle to form a nip area between the endless belt and the heat fixing roller for allowing a recording sheet to pass therethrough, the pressure member is pressed by way of the endless belt to the heat fixing roller at the nip area thereby forming distortion in the heat resistant elastic layer of the heat fixing roller. An image forming apparatus using the fixing device can satisfy improved image quality, extended working life, energy saving and high speed operation altogether.
    Type: Grant
    Filed: October 28, 1998
    Date of Patent: December 7, 1999
    Assignee: Fuji Xerox Co. Ltd.
    Inventors: Yoshio Kanesawa, Hirotaka Matsuoka, Yasuhiro Kusumoto, Yasuhiro Uehara
  • Patent number: 5968689
    Abstract: The present invention provides an image-forming material which can be removed easily from image-receiving paper while maintaining the fixability to the image-receiving paper; a preparation process thereof, and the image-receiving medium. The image-forming material according to the present invention can be prepared by dispersing an oil phase, which contains an organic solvent, a binding resin, and a releasing agent composed of a hydrophobic resin and/or a wax, in an aqueous phase as oil droplets; removing the solvent from the dispersion; and incorporating the releasing agent by separating the residue from the aqueous phase. The image-forming material according to the present invention contains at least a binding resin and the above-described releasing agent and the releasing agent is contained in an amount of 30 to 90 wt % in solid content.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: October 19, 1999
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Kaoru Torikoshi, Isamu Suzuki, Hirotaka Matsuoka
  • Patent number: 5935751
    Abstract: Disclosed is a toner for developing an electrostatic latent image comprising a binding resin and a colorant, wherein the toner contains from 0.1% to 40% by weight of wax, the amount of wax disposed on the surface of the toner is from 1% to 10% by weight, and the number-average dispersion diameter of the wax is from 0.1 to 2 .mu.m. The toner is produced by a process comprising a step of dissolving or dispersing each of the raw materials of the resin, colorant, and wax into an organic solvent to form an oil-phase component, and a step of granulating the oil-phase component in an aqueous solvent, or a step of granulating the oil-phase component in an aqueous solvent and a step of suspension-polymerizing the particles formed in the granulation step. It is desirable that the wax be finely dispersed beforehand and that the wax be flake-shaped.
    Type: Grant
    Filed: June 25, 1997
    Date of Patent: August 10, 1999
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Hirotaka Matsuoka, Hiroyuki Tanaka, Jong Won Lee, Isamu Suzuki
  • Patent number: 5783350
    Abstract: The developer for electrostatic photography according to the present invention comprises toner particles containing a thermoplastic resin and a colorant dispersed in an electrically insulating carrier having a melting point above room temperature wherein the thermoplastic resin is insoluble in the electrically insulating carrier at a temperature below the melting point of the electrically insulating carrier but becomes solvated with the electrically insulating carrier at a temperature above the melting point of the electrically insulating carrier. The present invention provides a developer for electrostatic photography, which enables to reduce the emission of vapor, to carry out a fixing treatment at a higher rate, to reduce the amount of energy required for fixing treatment and to create a high-quality image even after repeated use of the developer.
    Type: Grant
    Filed: December 9, 1996
    Date of Patent: July 21, 1998
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Hirotaka Matsuoka, Takako Kobayashi
  • Patent number: 5723250
    Abstract: A liquid developer for electrophotography is disclosed, which comprises a carrier, a charge director contained in the carrier, and toner particles dispersed in the carrier and having a volume-average particle diameter of from 0.5 .mu.m to 5 .mu.m, wherein the toner particles comprises a thermoplastic resin substantially insloluble in the carrier at a temperature used for development, a colorant dispersed in the resin, and a charge control agent. A process for producing the liquid developer, and a process for forming an image are also disclosed. Thereby, a liquid developer for electrophotography having good toner electrification characteristics and satisfactory charge stability is obtained.
    Type: Grant
    Filed: January 2, 1997
    Date of Patent: March 3, 1998
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Hirotaka Matsuoka, Takako Kobayashi, Ken Hashimoto
  • Patent number: 5622804
    Abstract: A liquid developer for electrophotography is disclosed, which comprises a carrier, a charge director contained in the carrier, and toner particles dispersed in the carrier and having a volume-average particle diameter of from 0.5 .mu.m to 5 .mu.m, wherein the toner particles comprises a thermoplastic resin substantially insoluble in the carrier at a temperature used for development, a colorant dispersed in the resin, and a charge control agent. A process for producing the liquid developer, and a process for forming an image are also disclosed. Thereby, a liquid developer for electrophotography having good toner electrification characteristics and satisfactory charge stability is obtained.
    Type: Grant
    Filed: April 14, 1995
    Date of Patent: April 22, 1997
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Hirotaka Matsuoka, Takako Kobayashi, Ken Hashimoto
  • Patent number: 5529874
    Abstract: A liquid developer for electrophotography comprising a carrier liquid having dispersed therein toner particles containing a binder resin and a colorant, wherein said carrier liquid contains at least one ether compound selected from compounds represented by formula (I) and compounds represented by formula (II):R.sub.1 --O(C.sub.n H.sub.2n O).sub.x --R.sub.2 (I)R.sub.3 --O--R.sub.4 (II)wherein R.sub.1, R.sub.2, R.sub.3, and R.sub.4, which may be the same or different, each represent an alkyl group, an alicyclic alkyl group, an aryl group, or an aralkyl group; n represents an integer of from 4 to 8; and x represents 1 or 2. The developer requires no heating even in winter and is less vaporized and less dangerous owing to the low solidifying point and low vapor pressure of the carrier liquid. The developer stably exhibits satisfactory charging properties. The developer is suited to high-speed copying.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: June 25, 1996
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Takako Kobayashi, Hirotaka Matsuoka, Ken Hashimoto
  • Patent number: 5404209
    Abstract: A method for forming images including the steps of: developing an electrostatic latent image formed on a latent image carrying member with a liquid developer including a carrier liquid; and bringing a toner image thus formed into contact with an oil absorbent selected from the group consisting of a network-forming oil-absorbent material and a gel-swelling oil-absorbent material, to remove the carrier liquid.
    Type: Grant
    Filed: January 6, 1994
    Date of Patent: April 4, 1995
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Hirotaka Matsuoka, Takako Kobayashi, Ken Hashimoto
  • Patent number: 5352557
    Abstract: A liquid developer for use in electrostatic photography comprises toner particles, each containing a resin and a colorant dispersed in a carrier liquid. The carrier liquid comprises at least one ether compound derived from ethylene glycol or propylene group and represented by the following general formulaR.sub.1 --O(C.sub.n H.sub.2n O).sub.x R.sub.2wherein R.sub.1 and R.sub.2 may be the same or different and represent an alkyl group or an aryl group, n is an integer of 2 or 3, and x is an integer of 1 to 3. The ether compound is present in the carrier liquid in the range of from 5 to 100 wt %.
    Type: Grant
    Filed: October 15, 1993
    Date of Patent: October 4, 1994
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Hirotaka Matsuoka, Takako Kobayashi, Ken Hashimoto
  • Patent number: 5288578
    Abstract: A positively chargeable carrier for developing electrostatic charge images having good surface staining resistance and good environmental reliance of charging is disclosed, which comprises a core material having formed thereon an interlayer having a triboelectrification controlling function and having a nitrogen atom content of from 5 ppm to 75 ppm based on the weight of the core material, and a releasable coated layer formed on the interlayer. A two-component developer using the carrier is also disclosed.
    Type: Grant
    Filed: May 13, 1992
    Date of Patent: February 22, 1994
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Yutaka Sugizaki, Susumu Saito, Hirotaka Matsuoka, Masanori Ichimura, Masaru Miura, Takashi Imai
  • Patent number: 5202210
    Abstract: A carrier for magnetic brush developer comprising a core material having coated thereon a coated layer containing a graft copolymer comprising a polymer of a nitrogen-containing vinyl monomer or a phosphorus-containing vinyl monomer having a molecular weight of from 1,000 to 5,500 graft-copolymerized thereto a vinyl monomer.
    Type: Grant
    Filed: October 15, 1991
    Date of Patent: April 13, 1993
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Hirotaka Matsuoka, Masanori Ichimura, Masaru Miura