Patents by Inventor Shinichiro Yagi

Shinichiro Yagi 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: 20040224247
    Abstract: An image formation method includes the steps of charging the surface of an electrophotographic photoconductor, exposing the charged photoconductor to a light image to form a latent electrostatic image on the photoconductor, developing the latent electrostatic image using a two-component developer containing a toner and a carrier to obtain a toner image, and transferring the toner image to an image receiving material directly or via an intermediate transfer member, with the photoconductor showing a surface friction coefficient of 0.40 or less, and the toner having toner particles with an average circularity of 0.930 or more.
    Type: Application
    Filed: June 21, 2004
    Publication date: November 11, 2004
    Inventors: Fumihiro Sasaki, Mitsuo Aoki, Yasuaki Iwamoto, Naohito Shimota, Kazuyuki Yazaki, Hiroaki Matsuda, Hiroshi Nakai, Kumi Hasegawa, Shinichiro Yagi, Hiroto Higuchi, Akemi Sugiyama
  • Publication number: 20040209181
    Abstract: A toner for developing latent electrostatic images is in the form of particles prepared by dissolving or dispersing each component of a composition in an organic solvent to form a solution or dispersion, the composition containing at least a resin reactive with a compound having an active hydrogen group, a compound having an active hydrogen group, a coloring agent, a releasing agent, and a graft polymer C of a polyolefin resin A on which a vinyl resin B has been at least partially grafted; dispersing the solution or dispersion in an aqueous medium; reacting the reactive resin with the compound having an active hydrogen group; removing the organic solvent during or after the step of reacting; and washing and drying particles formed by removing the organic solvent.
    Type: Application
    Filed: January 21, 2004
    Publication date: October 21, 2004
    Inventors: Hiroto Higuchi, Masami Tomita, Fumihiro Sasaki, Shigeru Emoto, Naohito Shimota, Maiko Kondo, Takahiro Honda, Junichi Awamura, Shinichiro Yagi, Toshiki Nanya, Tadao Takikawa
  • Publication number: 20040179861
    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: March 19, 2004
    Publication date: September 16, 2004
    Inventors: Satoshi Mochizuki, Naohito Shimota, Hiroaki Matsuda, Shinichiro Yagi, Tomomi Tamura, Tatsuya Niimi
  • Publication number: 20040175641
    Abstract: A toner has a storage elastic modulus (G′) of 500 Pa or more at a frequency of 1 Hz and temperature of 180° C., while the toner is obtained by dissolving or dispersing a toner composition in an organic solvent, further dispersing the solution or dispersion thereof in an aqueous medium containing fine resin particles as well as being reacted with a compound having an active hydrogen group, and removing the solvent from the obtained aqueous dispersion.
    Type: Application
    Filed: December 12, 2003
    Publication date: September 9, 2004
    Inventors: Toshiki Nanya, Masami Tomita, Shigeru Emoto, Shinichiro Yagi, Naohiro Watanabe, Tadao Takikawa
  • Patent number: 6787280
    Abstract: A toner for developing an electrostatic image, comprising toner particles each containing at least a colorant and a resin, and an external additive present on each of the toner particles, wherein the water wettability of said toner particles without the external additive is W0, wherein the water wettability of the toner is W100, and wherein (W100−W0)/W100 is not greater than 0.3.
    Type: Grant
    Filed: November 4, 2002
    Date of Patent: September 7, 2004
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Yamashita, Tsunemi Sugiyama, Shinichiro Yagi, Hiroshi Yamada, Masami Tomita, Toshiki Nanya, Shigeru Emoto, Naohiro Watanabe, Tadao Takigawa
  • Publication number: 20040157146
    Abstract: A dry toner is provided that is prepared by a method including the steps of (A) dissolving or dispersing a toner composition in an organic solvent to prepare a toner composition liquid and (B) dispersing the toner composition liquid in an aqueous liquid which contains a binder resin formed of a modified polyester (i) and a colorant containing a carbon black having a pH not greater than 7, wherein the toner has a volume average particle diameter (Dv) is from 3 to 7 &mgr;m and a ratio of the volume average particle diameter (Dv) to a number average particle diameter (Dp) is from 1.00 to 1.25.
    Type: Application
    Filed: December 1, 2003
    Publication date: August 12, 2004
    Inventors: Masami Tomita, Toshiki Nanya, Shigeru Emoto, Shinichiro Yagi, Hiroshi Yamada, Naohiro Watanabe, Tadao Takigawa
  • Publication number: 20040146795
    Abstract: A toner is used in an image forming process employing a toner recycling system and contains at least a modified polyester resin, a coloring agent, and a releasing agent. The toner has a volume-average particle diameter Dv, a number-average particle diameter Dn and a shape factor SF-1, wherein Dv is in a range from 4.0 &mgr;m to 6.0 &mgr;m, the ratio Dv/Dn of Dv to Dn is in a range from 1.00 to 1.30, and the shape factor SF-1 is in a range from 140 to 200.
    Type: Application
    Filed: January 20, 2004
    Publication date: July 29, 2004
    Inventors: Shigeru Emoto, Toshiki Nanya, Naohito Shimota, Maiko Kondo, Shinichiro Yagi, Hiroto Higuchi, Fumihiro Sasaki, Takahiro Honda, Junichi Awamura
  • Publication number: 20040142265
    Abstract: A dry toner contains at least a toner binder, organic fine particles, a colorant, a wax, a charge control agent, and an external additive. The wax is concentrated in the vicinity of a toner core including the toner binder, colorant and wax. The organic fine particles adhere to the surface of the toner core to form a base toner-particle, the fine particle of charge control agent adhere to the surface of the base toner-particle, and the external additive is located on the surface thereof.
    Type: Application
    Filed: November 14, 2003
    Publication date: July 22, 2004
    Inventors: Masami Tomita, Fumihiro Sasaki, Toshiki Nanya, Hiroto Higuchi, Shinichiro Yagi, Shigeru Emoto, Tomoyuki Ichikawa, Naohito Shimota, Maiko Kondo, Tadao Takikawa
  • Publication number: 20040131961
    Abstract: A toner composition including toner particles including a binder resin including a modified polyester resin, and a second resin having a weight average molecular weight of from 2,000 to 10,000; a colorant; a release agent; and a particulate material which is present at least a surface portion of the toner particles while embedded into the surface portion, wherein the binder resin has a glass transition temperature not lower than 35° C. and lower than 55° C., and wherein the particulate material has an average particle diameter of from 0.002 to 0.2 times that of the toner particles. A developer including the toner composition and a carrier having a layer thereon which includes at least an acrylic resin and a silicone resin, and a method for fixing an image of the toner composition are also provided.
    Type: Application
    Filed: September 26, 2003
    Publication date: July 8, 2004
    Applicant: RICOH COMPANY LIMITED
    Inventors: Yohichiroh Watanabe, Masanori Suzuki, Tsunemi Sugiyama, Hiroshi Yamashita, Takuya Saito, Naohiro Watanabe, Masami Tomita, Shigeru Emoto, Shinichiro Yagi, Hiroshi Yamada, Toshiki Nanya, Tadao Takigawa
  • Publication number: 20040126147
    Abstract: A method for developing an electrostatic latent image, including forming a magnet brush of a developer including a toner and a carrier on a developing sleeve including a main magnet and auxiliary magnets; and developing the electrostatic latent image with the magnet brush to form a toner image at a rubbing region, wherein the magnetic flux density in a normal line direction, half width, and attenuation ratio of the main magnet and the angle between the main magnet and auxiliary magnets are specified, and the magnetic sleeve has specific grooves thereon, and wherein the toner has a volume average particle diameter of from 4.0 to 7.0 &mgr;m, and includes fine particles having a circle equivalent diameter not greater than 2 &mgr;m in an amount not greater than 20% by number.
    Type: Application
    Filed: September 22, 2003
    Publication date: July 1, 2004
    Inventors: Maiko Kondo, Fumihiro Sasaki, Toshiki Nanya, Shinichiro Yagi, Masami Tomita, Shigeru Emoto, Naohito Shimota, Hiroto Higuchi, Tomoyuki Ichikawa
  • Patent number: 6757507
    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: Grant
    Filed: December 19, 2001
    Date of Patent: June 29, 2004
    Assignee: Ricoh Company, Ltd.
    Inventors: Satoshi Mochizuki, Naohito Shimota, Hiroaki Matsuda, Shinichiro Yagi, Tomomi Tamura, Tatsuya Niimi
  • Patent number: 6753955
    Abstract: An inspection object silicon wafer for the purpose of detecting crystal defects and the method of detection thereof, which make easy the detection of the number and location of the defects formed on the surface of the silicon wafer by performing heat treatment and epitaxial growth under a temperature condition in which the natural oxide film is removed but the state of the surface of the silicon wafer is preserved, specifically under a hydrogen atmosphere of normal pressure and a temperature between 900° C. and 1080° C., through which defects having pits and projections are generated on the surface of the epitaxial layer, and by detecting the defects having pits and protrusions by a light scattering type particle inspection apparatus.
    Type: Grant
    Filed: December 11, 2001
    Date of Patent: June 22, 2004
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventor: Shinichiro Yagi
  • 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
  • Publication number: 20040053154
    Abstract: A toner for developing a latent electrostatic image including a base of toner particle which contains a binder resin and a coloring agent, and an external additive. Herein, a plurality of the base of toner particle has a volume average particle diameter (Dv) of 3 &mgr;m to 7 &mgr;m, a ratio (Dv/Dn) of the volume average particle diameter (Dv) to a number average particle diameter (Dn) is 1.01 to 1.25, a plurality of the base of toner particle contains 15% by number or less of the base of toner particle having a particle diameter of 0.6 &mgr;m to 2.0 &mgr;m, a plurality of the base of toner particle has a circularity of 0.930 to 0.990 on average, the binder resin contains a modified polyester resin, and the toner contains 0.3 parts by weight to 5.0 parts by weight of the external additive, relative to 100 parts by weight of the base of toner particle.
    Type: Application
    Filed: June 27, 2003
    Publication date: March 18, 2004
    Inventors: Masami Tomita, Tadao Takikawa, Tomoyuki Ichikawa, Fumihiro Sasaki, Toshiki Nanya, Hiroto Higuchi, Shigeru Emoto, Shinichiro Yagi, Naohito Shimota, Maiko Kondo
  • Publication number: 20030180644
    Abstract: A toner for developing an electrostatic image, including a colorant, a binder resin comprising a modified polyester, and fine resin particles having a weight average particle diameter of 50 to 300 nm and being present on an outer surface of the toner, wherein the toner has a BET specific surface area of 1.5 to 4.0 m2/g.
    Type: Application
    Filed: March 24, 2003
    Publication date: September 25, 2003
    Inventors: Toshiki Nanya, Masami Tomita, Shigeru Emoto, Hiroshi Yamada, Shinichiro Yagi, Naohiro Watanabe, Tadao Takigawa
  • Publication number: 20030162115
    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): 1
    Type: Application
    Filed: November 27, 2002
    Publication date: August 28, 2003
    Inventors: Osamu Uchinokura, Hiroyuki Fushimi, Kohki Katoh, Shinichiro Yagi, Toshiki Nanya
  • Publication number: 20030162112
    Abstract: A toner for developing an electrostatic image, comprising toner particles each containing at least a colorant and a resin, and an external additive present on each of the toner particles, wherein the water wettability of said toner particles without the external additive is W0, wherein the water wettability of the toner is W100, and wherein (W100−W0)/W100 is not greater than 0.3.
    Type: Application
    Filed: November 4, 2002
    Publication date: August 28, 2003
    Inventors: Hiroshi Yamashita, Tsunemi Sugiyama, Shinichiro Yagi, Hiroshi Yamada, Masami Tomita, Toshiki Nanya, Shigeru Emoto, Naohiro Watanabe, Tadao Takigawa
  • Publication number: 20030152859
    Abstract: A toner comprising:
    Type: Application
    Filed: November 4, 2002
    Publication date: August 14, 2003
    Applicant: RICOH COMPANY, LTD.
    Inventors: Shigeru Emoto, Tsunemi Sugiyama, Hiroshi Yamashita, Shinichiro Yagi, Masami Tomita, Hiroshi Yamada, Naohiro Watanabe, Toshiki Nanya
  • Publication number: 20030138717
    Abstract: Toner particles including a binder resin; a colorant; and a particulate resin which is present at least on a surface of the toner particles and which has a glass transition temperature of form 50 to 90° C., wherein a ratio (Dv/Dn) of a volume average particle diameter (Dv) of the toner particles to a number average particle diameter (Dn) thereof is from 1.00 to 1.40 and the surface of the toner particles is covered with the particulate resin at a covering ratio of from 1 to 90 %. A method for manufacturing the toner particles is provided. A developer including a toner including the toner particles is provided. A developing method using a toner including the toner particles is provided. A toner container containing the toner particles is provided.
    Type: Application
    Filed: October 31, 2002
    Publication date: July 24, 2003
    Applicant: RICOH COMPANY LIMITED
    Inventors: Shinichiro Yagi, Masami Tomita, Toshiki Nanya, Shigeru Emoto, Hiroshi Yamada, Hiroshi Yamashita, Naohiro Watanabe, Tsunemi Sugiyama, Tadao Takigawa
  • 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