Patents by Inventor Tatsuya Niimi

Tatsuya Niimi 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: 20040120730
    Abstract: The present invention relates to the electrophotographic apparatus wherein the photoconductor takes 200 msec or less to reach from the light irradiator to the developer, an exposure energy upon irradiation of a write light having a resolution of 600 dpi or greater from the light irradiator to the photoconductor is 5 erg/cm2 or less on the surface thereof, the photoconductor is obtained by stacking a charge generation layer and a charge transport layer in this order on a conductive support, and the charge generation layer contains titanyl phthalocyanine crystals having, as a diffraction peak (±0.2°) of Bragg angle 2&thgr; relative to CuK&agr; ray (wavelength: 1.542 angstrom), a maximum diffraction peak at least at 27.2°, main peaks at 9.4°, 9.6° and 24.0°, and a peak at 7.3° as a diffraction peak on the lowest angle side, and not having a peak within a range of 7.4 to 9.3°.
    Type: Application
    Filed: September 8, 2003
    Publication date: June 24, 2004
    Inventors: Tatsuya Niimi, Naohiro Toda
  • Publication number: 20040053149
    Abstract: A photoreceptor including an electroconductive substrate; a charge generation layer located overlying the electroconductive substrate optionally with an intermediate layer therebetween; and a charge transport layer formed overlying the charge generation layer using a non-halogenated solvent and including a charge transport material and a resin, wherein the charge generation layer includes a polyvinyl acetal resin and a charge generation material having an average particle diameter less than a roughness of a surface of either the electroconductive substrate or the intermediate layer, on which the charge generation layer is located.
    Type: Application
    Filed: June 27, 2003
    Publication date: March 18, 2004
    Inventors: Naohiro Toda, Tatsuya Niimi
  • Publication number: 20040048178
    Abstract: An electrophotographic photoreceptor including an electroconductive substrate; a photosensitive layer located overlying the electroconductive substrate and including a resin; and a surface layer including a filler and a binder resin, wherein the surface layer and the photosensitive layer have a continuous structure, and wherein the surface layer satisfies the following relationship: &sgr;≦D/5, wherein D represents an average of maximum thicknesses of the surface layer in units of micrometers in 20 segments of 5 &mgr;m wide when a portion of a cross section of the photoreceptor of 100 &mgr;m wide is divided into the 20 segments, and &sgr; represents a standard deviation of the 20 maximum thicknesses.
    Type: Application
    Filed: August 12, 2003
    Publication date: March 11, 2004
    Inventors: Hiroshi Ikuno, Hidetoshi Kami, Ryohichi Kitajima, Narihito Kojima, Akihiko Matsuyama, Hiroshi Nagame, Katsuichi Ohta, Tetsuro Suzuki, Nozomu Tamoto, Hiroshi Tamura, Yohta Sakon, Eiji Kurimoto, Tatsuya Niimi, Yuka Miyamoto
  • Publication number: 20040033428
    Abstract: A titanylphthalocyanine crystal having an X-ray diffraction spectrum having plural diffraction peaks and a primary particle diameter not greater than 0.2 &mgr;m, wherein a maximum diffraction peak is observed at a Bragg (2&thgr;) angle of 27.2±0.2°; main peaks are observed at 9.4°, 9.6° and 24.0°; and a minimum diffraction peak is observed at 7.3°; and preferably no diffraction peak is observed at an angle greater than 7.3° and less than 9.4° when a specific X-ray of CuK&agr; having a wavelength of 1.542 Å irradiates the titanylphthalocyanine crystal.
    Type: Application
    Filed: June 5, 2003
    Publication date: February 19, 2004
    Inventor: Tatsuya Niimi
  • Patent number: 6677091
    Abstract: A photoreceptor that can be repeatedly used to produce high-quality images steadily is described, as well as an electrophotographic apparatus that can be used to producing high-quality images even after repeated use. The electrophotographic photoreceptor has a protective layer thereon, in which the grain size distribution of the fillers continuously or gradually increases from the photosensitive layer side to the surface side. Meanwhile, the electrophotographic photoreceptor is used in the electrophotographic apparatus.
    Type: Grant
    Filed: March 22, 2002
    Date of Patent: January 13, 2004
    Assignee: Ricoh Company, Ltd.
    Inventor: Tatsuya Niimi
  • Patent number: 6653033
    Abstract: An electrophotographic photoconductor having an electroconductive support, and a photoconductive layer formed on the support and having an outwardly facing surface. The photoconductive layer includes a charge transporting material, a charge generating material and an inorganic filler including &agr;-alumina, wherein the concentration of the inorganic filler in the photoconductive layer decreases stepwise or continuously in the direction from the outwardly facing surface thereof to the opposite surface thereof.
    Type: Grant
    Filed: March 4, 2003
    Date of Patent: November 25, 2003
    Assignee: Ricoh Company, Ltd.
    Inventors: Hidetoshi Kami, Tatsuya Niimi, Akihiko Matuyama, Nozomu Tamoto, Eiji Kurimoto
  • Patent number: 6641964
    Abstract: An electrophotographic photoreceptor including an electroconductive substrate; a photosensitive layer located overlying the electroconductive substrate and including a resin; and a surface layer including a filler and a binder resin, wherein the surface layer and the photosensitive layer have a continuous structure, and wherein the surface layer satisfies the following relationship: &sgr;≦D/5, wherein D represents an average of maximum thicknesses of the surface layer in units of micrometers in 20 segments of 5 &mgr;m wide when a portion of a cross section of the photoreceptor of 100 &mgr;m wide is divided into the 20 segments, and &sgr; represents a standard deviation of the 20 maximum thicknesses.
    Type: Grant
    Filed: November 2, 2001
    Date of Patent: November 4, 2003
    Assignee: Ricoh Company Limited
    Inventors: Hiroshi Ikuno, Hidetoshi Kami, Ryohichi Kitajima, Narihito Kojima, Akihiko Matsuyama, Hiroshi Nagame, Katsuichi Ohta, Tetsuro Suzuki, Nozomu Tamoto, Hiroshi Tamura, Yohta Sakon, Eiji Kurimoto, Tatsuya Niimi, Yuka Miyamoto
  • Publication number: 20030190539
    Abstract: An image forming apparatus including a photoreceptor, wherein the photoreceptor includes an image forming portion having two ends substantially parallel to the rotating direction and a gap forming member located outside of each of the two ends of the image forming portion; a charging roller configured to charge the photoreceptor, wherein the charging roller contacts the gap forming members of the photoreceptor to form a gap g between the surface of the image forming portion and the peripheral surface thereof; an imagewise light irradiator; an image developer; and an image transfer device, wherein the relationship t≧2g is satisfied, where g represents the gap and t represents a distance between an inside edge of one of the gap forming members and nearer one of the two ends of the image forming portion of the photoreceptor.
    Type: Application
    Filed: July 26, 2002
    Publication date: October 9, 2003
    Inventor: Tatsuya Niimi
  • Publication number: 20030138718
    Abstract: A method for forming an electrophotographic image and a device for forming an image on a transfer material by the steps for charging, exposing, developing and transferring, and recovering the toner remained untransferred in the step for cleaning by recovering, wherein the toner used in the step for developing has a total surface area ratio Z of additive, which is calculated by Z=(Ht·Wt)/(H·W), satisfies 0.5≦Z≦1.5, the electrophotographic photoconductor used comprises at least a photosensitive layer and a filler-containing protective layer provided on a conductive support in that order, and the angle of repose of the toner to the protective layer surface of the electrophotographic photoconductor is 30° or less.
    Type: Application
    Filed: June 24, 2002
    Publication date: July 24, 2003
    Inventors: Shinichiro Yagi, Naohito Shimoto, Tatsuya Niimi, Satoshi Mochizuki, Hiroaki Matsuda, Tomomi Tamura
  • Publication number: 20030113642
    Abstract: A photoreceptor including an electroconductive substrate; and a photosensitive layer located overlying the electroconductive substrate and comprising a charge generation material, a charge transport material and an inorganic filler, wherein the content of the inorganic filler at a surface side of the photosensitive layer is greater than that at a bottom side of the photosensitive layer near the electroconductive substrate, and wherein an outermost layer of the photoreceptor has a water vapor permeability not greater than 50 g·m−2·24 h−1.
    Type: Application
    Filed: May 1, 2002
    Publication date: June 19, 2003
    Inventors: Hidetoshi Kami, Tatsuya Niimi, Akihiko Matsuyama, Eiji Kurimoto, Nozomu Tamoto
  • Patent number: 6576388
    Abstract: An electrophotographic photoreceptor including at least an electroconductive substrate; and a photosensitive layer overlying the electroconductive substrate and including at least a charge generation layer; a charge transport layer; and a protective layer including a filler, wherein the filler is dispersed in the protective layer so as to occupy an area of from 3 to 5% of a cross section of the protective layer; the filler has particle diameter distribution having a peak at a diameter of from 0.2 to 0.3 &mgr;m; and the particles of the filler having a particle diameter of not less than 0.3 &mgr;m occupies an area of from 10 to 30% of the area of all the filler in the cross section of the protective layer.
    Type: Grant
    Filed: November 2, 2001
    Date of Patent: June 10, 2003
    Assignee: Ricoh Company Limited
    Inventors: Yohta Sakon, Akio Kosuge, Tatsuya Niimi, Narihito Kojima
  • Publication number: 20030104295
    Abstract: A photoreceptor that can be repeatedly used to produce high-quality images steadily is described, as well as an electrophotographic apparatus that can be used to producing high-quality images even after repeated use. The electrophotographic photoreceptor has a protective layer thereon, in which the grain size distribution of the fillers continuously or gradually increases from the photosensitive layer side to the surface side. Meanwhile, the electrophotographic photoreceptor is used in the electrophotographic apparatus.
    Type: Application
    Filed: March 22, 2002
    Publication date: June 5, 2003
    Inventor: Tatsuya Niimi
  • Patent number: 6573016
    Abstract: An electrophotographic photoconductor having an electroconductive support, and a photoconductive layer formed on the support and having an outwardly facing surface. The photoconductive layer includes a charge transporting material, a charge generating material and an inorganic filler including &agr;-alumina, wherein the concentration of the inorganic filler in the photoconductive layer decreases stepwise or continuously in the direction from the outwardly facing surface thereof to the opposite surface thereof.
    Type: Grant
    Filed: November 2, 2001
    Date of Patent: June 3, 2003
    Assignee: Ricoh Company, Ltd.
    Inventors: Hidetoshi Kami, Tatsuya Niimi, Akihiko Matuyama, Nozomu Tamoto, Eiji Kurimoto
  • Patent number: 6562531
    Abstract: An electrophotographic photoreceptor including at least an electroconductive substrate, a photosensitive layer formed on the substrate and a protective layer formed on the photosensitive layer and including a binder resin, wherein when a solution in which the binder resin is dissolved in an organic solvent incompatible with water is mixed with deionized water having an electroconductivity not greater than 1 &mgr;S/cm and substantially the same weight as that of the solvent while agitating, the water has an electroconductivity not greater than 2 &mgr;S/cm.
    Type: Grant
    Filed: July 13, 2001
    Date of Patent: May 13, 2003
    Assignee: Ricoh Company, Ltd.
    Inventor: Tatsuya Niimi
  • Patent number: 6558863
    Abstract: A photoreceptor including an electroconductive substrate and a photosensitive layer which is formed on the electroconductive substrate and which includes a charge generation material, wherein the charge generation material comprises an organic pigment and wherein the photosensitive layer further includes at least one ion selected from the group consisting of K+, Na+, NO3−, HCOO−, NO2−, Cl−, Br−, and NH4+ or one or more water-soluble inorganic salts.
    Type: Grant
    Filed: December 13, 2000
    Date of Patent: May 6, 2003
    Assignee: Ricoh Company Limited
    Inventors: Takashi Rokutanzono, Tamotsu Aruga, Tatsuya Niimi, Yoshiaki Kawasaki
  • Publication number: 20030073015
    Abstract: An electrophotographic photoreceptor including an electroconductive substrate, a photosensitive layer located overlying the electroconductive substrate, and optionally a protective layer overlying the photosensitive layer, wherein an outermost layer of the photoreceptor includes a filler, a binder resin and an organic compound having an acid value of from 10 to 700 mgKOH/g. The photosensitive layer can be the outermost layer. A coating liquid for an outermost layer of a photoreceptor including a filler, a binder resin, an organic compound having an acid value of from 10 to 700 mgKOH/g and plural organic solvents. A method for preparing a photoreceptor including forming a. photosensitive layer, and coating the coating liquid on the photosensitive layer. An image forming method and apparatus and a process cartridge using the photoreceptor are also provided.
    Type: Application
    Filed: November 2, 2001
    Publication date: April 17, 2003
    Inventors: Nozomu Tamoto, Tetsuro Suzuki, Hiroshi Tamura, Tatsuya Niimi, Akihiko Matsuyama, Eiji Kurimoto, Hidetoshi Kami
  • Patent number: 6516169
    Abstract: An image forming apparatus including a photoreceptor having an image forming portion; a charging roller having a gap forming member on both ends thereof to form a gap between the photoreceptor and the charging roller and configured to charge the photoreceptor, wherein the gap forming members do not contact the image forming portion, and wherein the relationship t≧2g is satisfied; a light irradiator configured to form a latent image in the image forming portion; an image developer configured to form a toner image on the photoreceptor; and an image transferer configured to transfer the toner image onto a receiving material, wherein g is the gap and t represents a distance between an inside edge of one of the gap forming members and one of the two ends of the image forming portion closer to the inside edge of the gap forming member.
    Type: Grant
    Filed: August 31, 2001
    Date of Patent: February 4, 2003
    Assignee: Ricoh Company Limited
    Inventors: Tatsuya Niimi, Yohta Sakon
  • Publication number: 20030002078
    Abstract: A server computer searches for at least one printing-service proving store based on printing-condition information sent form an information terminal, and sends information representing the searched printing-service providing store to the information terminal. After a user selects one printer device based on the information representing the at least one printing-service providing store, the information terminal sends document data to be printed to the server computer. The server computer sends printing data to be printed to the user-selected printer device.
    Type: Application
    Filed: July 1, 2002
    Publication date: January 2, 2003
    Applicant: Ricoh Company, Ltd.
    Inventors: Naohiro Toda, Takashi Rokutanzono, Shinji Nousyo, Tatsuya Niimi
  • Publication number: 20020197549
    Abstract: An electrophotographic photoreceptor including at least an electroconductive substrate; and a photosensitive layer overlying the electroconductive substrate and including at least a charge generation layer; a charge transport layer; and a protective layer including a filler, wherein the filler is dispersed in the protective layer so as to occupy an area of from 3 to 5% of a cross section of the protective layer; the filler has particle diameter distribution having a peak at a diameter of from 0.2 to 0.3 &mgr;m; and the particles of the filler having a particle diameter of not less than 0.3 &mgr;m occupies an area of from 10 to 30% of the area of all the filler in the cross section of the protective layer.
    Type: Application
    Filed: November 2, 2001
    Publication date: December 26, 2002
    Inventors: Yohta Sakon, Akio Kosuge, Tatsuya Niimi, Narihito Kojima
  • Publication number: 20020181971
    Abstract: An image formation apparatus develops an electrostatic latent image with a two-component developer consisting of magnetic carriers and toners by using a development apparatus and a latent image supporter including a filler in an outermost layer thereof, the development apparatus having a developer supporter, which has an internally fixed magnetic body and rotates while supporting a developer on a surface thereof, and a developer quantity controller controlling a quantity of the developer which is supported by the developer supporter facing the magnetic body and controlling a height of magnetic brushes and consisting of materials having rigidity or rigidity and magnetic properties, wherein a ratio (Gp/Gd) of a development gap to a doctor gap between the developer supporter and the controller is from 0.7 to 1.0, and a weight-averaged particle diameter of a developer carrier is from 20 to 60 &mgr;m.
    Type: Application
    Filed: December 19, 2001
    Publication date: December 5, 2002
    Inventors: Satoshi Mochizuki, Naohito Shimota, Hiroaki Matsuda, Shinichiro Yagi, Tomomi Tamura, Tatsuya Niimi