Chemically Identified Carrier For Dry Toner Patents (Class 430/111.1)
  • Patent number: 8012662
    Abstract: A method of manufacturing toner including; melting and kneading a mixture including a binder resin and a coloring agent; cooling down the melted and kneaded mixture to provide a cooled mixture; coarsely pulverizing the cooled mixture to provide a coarsely pulverized mixture; finely pulverizing the coarsely pulverized mixture by supplying it via a pulverized material supply to a pulverizer that includes a rotation axis, a rotor attached to the rotation axis, and stators arranged around the rotor with a gap between the stators and the surface of the rotor and that performs pulverization in a circular space formed by the gap; and classifying the finely pulverized material by a classifier into at least fine powder, a toner product and coarse powder, wherein the coarse powder is returned to the pulverized material supply as part of the coarsely pulverized mixture.
    Type: Grant
    Filed: March 13, 2008
    Date of Patent: September 6, 2011
    Assignee: Ricoh Company Limited
    Inventor: Tohru Suganuma
  • Patent number: 7998649
    Abstract: Pigment particles with at least one metal oxide surface additive, wherein the at least one metal oxide surface additive is a metal oxide particle covalently bonded with at least one polycondensation polymer, wherein the pigment particle is a pearlescent or metallic pigment.
    Type: Grant
    Filed: March 3, 2008
    Date of Patent: August 16, 2011
    Assignee: Xerox Corporation
    Inventors: Karen A. Moffat, Valerie M. Farrugia, Ke Zhou, Richard P. N. Veregin, Cuong Vong, Eric M. Strohm, Wafa F. Bashir
  • Publication number: 20110195357
    Abstract: Disclosed are a resin-filled ferrite carrier core material for an electrophotographic developer, including a porous ferrite particle, wherein the composition of the porous ferrite particle is represented by the following formula (1), and part of (MgO) and/or (Fe2O3) in the following formula (1) is replaced with SrO; a ferrite carrier obtained by filling a resin in the voids of the ferrite carrier core material; and an electrophotographic developer using the ferrite carrier: ( MgO ) × ( Fe 2 ? O 3 ) ? y ? ( x = 10 ? ? mol ? ? % ? ? or ? ? more ? ? and ? ? less ? ? than ? ? 25 ? ? mol ? ? % y = exceeding ? ? 75 ? ? mol ? ? % ? ? and ? ? 90 ? ? mol ? ? % ? ? or ? ? less x + y = 100 ? ? mol ? ? % ) ( 1 )
    Type: Application
    Filed: February 2, 2011
    Publication date: August 11, 2011
    Applicant: POWDERTECH CO., LTD.
    Inventors: Takao SUGIURA, Takashi HIKICHI, Hiromichi KOBAYASHI
  • Publication number: 20110171573
    Abstract: A carrier for use in a two component developer for developing an electrostatic latent image is provided. The carrier includes a particulate core material; and a cover layer located on a surface of the core material and including a silicone resin and barium sulfate. The cover layer includes Ba and Si at an atomic ratio of from 0.01 to 0.08 as determined by X-ray photoelectron spectroscopy.
    Type: Application
    Filed: December 27, 2010
    Publication date: July 14, 2011
    Inventors: Koichi SAKATA, Minoru Masuda, Hisashi Nakajima, Kimitoshi Yamaguchi, Yutaka Takahashi, Hitoshi Iwatsuki, Saori Yamada, Toyoaki Tano
  • Publication number: 20110070538
    Abstract: The present disclosure provides carriers for use with toner compositions. In embodiments, a carrier may include a core, having a dry powder polymer coating. In embodiments, the coating may also include a colorant, such as carbon black. Processes for coating such carriers with the dry powder polymer coatings are also provided.
    Type: Application
    Filed: September 21, 2009
    Publication date: March 24, 2011
    Applicant: XEROX CORPORATION
    Inventors: Daryl W. Vanbesien, Michael S. Hawkins, Suxia Yang, Richard P.N. Veregin, Karen Ann Moffat
  • Publication number: 20110045399
    Abstract: An electrostatic image developing carrier includes a ferrite particle and a resin layer that coats the ferrite particle, wherein a magnesium element content of the ferrite particle is from about 3.0% by weight to about 20.0% by weight; wherein a manganese element content of the ferrite particle is from about 0.2% by weight to about 0.8% by weight; and wherein a content of toluene is more than about 100 ppm and not more than about 2,000 ppm.
    Type: Application
    Filed: April 7, 2010
    Publication date: February 24, 2011
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Takeshi Shoji, Akihiro Iizuka, Yosuke Tsurumi, Fusako Kiyono
  • Patent number: 7887985
    Abstract: A carrier and a two-component developer are provided. A coating resin layer for coating a core material contains fine particles of titanium oxide which comprise an anatase-type crystal and a rutile-type crystal, and a carrier coating amount of the coating resin layer falls in a range of from 5% by weight to 20% by weight. In addition, a content rate of the rutile-type crystal falls in a range of from 5% to 20% on the basis of the total amount of crystal, and the weight of the fine particles of titanium oxide falls in a range of from 5% by weight to 50% by weight relative to the weight of the core material. Further, the primary particle size of the fine particles of titanium oxide falls in a range of from 40 nm to 80 nm.
    Type: Grant
    Filed: December 27, 2007
    Date of Patent: February 15, 2011
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Toru Nishikawa
  • Patent number: 7879521
    Abstract: An objective is to provide a highly durable carrier for a developer which is capable of forming a high-definition image stably with no deterioration of a developing property since the carrier resistance and the charging ability remain stable even though the developer is used for a long duration; a method of manufacturing the carrier; and an image forming method employing the same. Disclosed is an electrophotographic carrier comprising a carrier core material and provided thereon, a resin-coated layer comprising charge control particles and low-resistive particles, wherein an initial carrier resistance is 5×108-3×1010 ?cm; a concentration of the low-resistive particles grows higher toward a surface of the layer from an inner part of the layer; and a concentration of the charge control particles grows lower toward a surface of the layer from an inner part of the layer.
    Type: Grant
    Filed: May 31, 2007
    Date of Patent: February 1, 2011
    Assignee: Konica Minolta Business Technologies, Inc.
    Inventors: Hiroyuki Kozuru, Yoshiaki Kobayashi, Tatsuya Nagase
  • Patent number: 7879522
    Abstract: There are adopted: a carrier core material for an electrophotographic developer, including Mg, Ti and Fe as main components, and containing Fe, Mg and Ti in contents of 52 to 66% by weight, 3 to 12% by weight and 0.2 to 12% by weight, respectively; an electrophotographic developer carrier prepared by coating with a resin the surface of the carrier core material; and an electrophotographic developer using the carrier.
    Type: Grant
    Filed: January 30, 2009
    Date of Patent: February 1, 2011
    Assignee: Powdertech Co., Ltd.
    Inventors: Koji Aga, Issei Shinmura, Tetsuya Igarashi
  • Publication number: 20110013948
    Abstract: Objects of the present invention are to provide a carrier core material for an electrophotographic developer having a true spherical shape and excellent strength, and a controllable true density and/or apparent density, and a method for manufacturing the carrier core material, a carrier and a method for manufacturing the carrier, and an electrophotographic developer using the carrier. In order to achieve the objects, there are employed a carrier core material for an electrophotographic developer, containing 3 to 100% by number of hollow particles having an iron content of 36 to 78% by weight, and a carrier for an electrophotographic developer, obtained by coating a resin on a surface of the carrier core material, and methods for manufacturing these, and an electrophotographic developer using the carrier.
    Type: Application
    Filed: February 27, 2009
    Publication date: January 20, 2011
    Applicant: POWDERTECH CO., LTD.
    Inventors: Koji Aga, Issei Shinmura, Tetsuya Igarashi
  • Publication number: 20110008724
    Abstract: A two-component developer is provided. The two-component developer includes a toner containing a binder resin, a colorant and a release agent, and a resin-coated carrier composed of a carrier core material and a resin coating layer formed on a surface of the carrier core material. The toner has an exposure rate of the release agent on the toner surface of 1.00% or above and 3.07% or below. The carrier core material has an apparent density of 1.86 g/cm3 or more and 2.45 g/cm3 or less. The exposure rate of the release agent of the toner and the apparent density of the carrier core material satisfy the following formula (1): y??1.54x+5.93 ??(1) wherein y represents the exposure rate of the release agent of the toner, and x represents the apparent density of the carrier core material.
    Type: Application
    Filed: July 13, 2010
    Publication date: January 13, 2011
    Inventors: Nobuyuki YOSHIOKA, Takanori Kamoto, Osamu Wada, Tadashi Iwamatsu
  • Publication number: 20100330493
    Abstract: Disclosed are particles which are useful as an external toner additive which can control physical properties of a toner. Specifically disclosed are surface-modified complex oxide particles which are obtained by surface-modifying silica-titania complex oxide particles produced by a dry process.
    Type: Application
    Filed: December 24, 2008
    Publication date: December 30, 2010
    Inventors: Masanobu Kaneeda, Akira Inoue, Paul Brandl
  • Publication number: 20100330492
    Abstract: The invention provides a carrier for electrostatic development, including ferrite particles and a coating layer including a resin having a cycloalkyl group, the ferrite particles including strontium in an amount of from about 0.1% by weight to about 1.0% by weight and having a BET specific surface area of from about 0.13 m2/g to about 0.23 m2/g.
    Type: Application
    Filed: November 19, 2009
    Publication date: December 30, 2010
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Yosuke TSURUMI, Akihiro IIZUKA, Fusako KIYONO, Takeshi SHOJI
  • Publication number: 20100279224
    Abstract: In a method for coating electrophotographic carrier core surfaces with a resin composition by rotating a rotator having a plurality of agitating blades on its surface in a casing; a coating treatment material that is introduced to a space defined between the rotator and the casing is in a packing of from 50% to 98% by volume; at the time of coating treatment, the electrophotographic carrier core surfaces are coat-treated with the resin composition while being put forward and put backward; and the electrophotographic carrier cores and the resin composition are, at the time of coating treatment, temperature-controlled at a specific temperature T (° C.) or below. This method enables the electrophotographic carrier core surfaces to be more uniformly coated with a coating resin.
    Type: Application
    Filed: December 18, 2008
    Publication date: November 4, 2010
    Applicant: Canon Kabushiki Kaisha
    Inventors: Naoki Okamoto, Yoshinobu Baba, Koh Ishigami, Tomoko Endo
  • Patent number: 7824833
    Abstract: A spherical resin-coated ferrite carrier for an electrophotographic developer which can maintain a stable resistance and chargeability, a favorable charge rising property because of an excellent fluidity, and has a suitable durability, its production method which is excellent in economic efficiency and production stability, and an electrophotographic developer using the resin-coated ferrite carrier, are provided. A resin-coated ferrite carrier for an electrophotographic developer which is a spherical resin-coated ferrite carrier, wherein a carrier core material thereof has an irregular surface to improve the adhesive strength to a resin coat, and wherein the irregularity of the surface takes a finely streaked wrinkle pattern, its production method, and an electrophotographic developer using the resin-coated ferrite carrier, are employed.
    Type: Grant
    Filed: November 30, 2006
    Date of Patent: November 2, 2010
    Assignee: Powdertech Co., Ltd.
    Inventors: Kanao Kayamoto, Issei Shinmura, Toshio Honjo
  • Publication number: 20100248125
    Abstract: A resin-filled ferrite carrier for an electrophotographic developer obtained by filling voids of a porous ferrite core material with a resin, wherein the resin is a silicone resin having a phenyl group, and an electrophotographic developer using this ferrite carrier.
    Type: Application
    Filed: March 19, 2010
    Publication date: September 30, 2010
    Applicant: POWDERTECH CO., LTD.
    Inventors: Takashi HIKICHI, Takao SUGIURA
  • Publication number: 20100233612
    Abstract: A carrier for an electrophotographic developer in which a surface of a carrier core particle is coated with a silicone resin or a modified silicone resin, the coated resin containing a dioctyltin compound, and the silicon content and dioctyltin content in the coating resin satisfy the following expression, and an electrophtographic developer using the carrier. 0.5?(dioctyltin content/silicon content)×100?11.
    Type: Application
    Filed: March 3, 2010
    Publication date: September 16, 2010
    Applicant: POWDERTECH CO., LTD.
    Inventors: Tetsuya UEMURA, Tomoaki KOBAYASHI, Masashi AOKI
  • Publication number: 20100233613
    Abstract: A carrier which is capable of avoiding excess blocking of the carrier particles at the time of forming a covering layer and is excellent in durability, a developer containing the carrier, and a developer container containing the developer, as well as an image forming method and a process cartridge which use the developer are provided. A carrier including at least a core material particle and a covering layer, a surface of the core material particle being covered with the covering layer, wherein the covering layer contains a condensate which is obtained by condensation of a silicone resin having at least one of a silanol group and a functional group which can be converted to the silanol group by hydrolysis, using a titanium diisopropoxy bis(ethylaceto-acetate) catalyst.
    Type: Application
    Filed: March 10, 2010
    Publication date: September 16, 2010
    Inventors: Minoru MASUDA, Kimitoshi Yamaguchi, Yutaka Takahashi, Koichi Sakata, Hitoshi Iwatsuki, Toyoaki Tano
  • Publication number: 20100216066
    Abstract: A transparent toner for electrostatic latent image developing, including a binder resin and a release agent, the difference between Tm and Tc being from about 30° C. to about 50° C., wherein Tm is an endothermic peak temperature of the release agent determined in a temperature rising process and Tc is an exothermic peak temperature of the release agent determined in a temperature decreasing process, in a measurement by a differential scanning calorimeter (DSC) according an ASTM method, and the toner having a weight average molecular weight of from about 35,000 to about 70,000.
    Type: Application
    Filed: September 25, 2009
    Publication date: August 26, 2010
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Yasuo Kadokura, Atsushi Sugawara, Masaru Takahashi, Yusuke Ikeda, Masanobu Ninomiya
  • Publication number: 20100203441
    Abstract: An electrostatic image developing toner includes toner mother particles that contain a binder resin, a coloring agent, and a release agent; and an external additive that contains a zinc-containing particles, wherein the number of free zinc-containing particles in all toner particles is from about by number to about 1.0% by number, and the free zinc-containing particles have a number average particle size of from about 1.0 ?m to about 3.0 ?m and an average circularity of from about 0.2 to about 0.6.
    Type: Application
    Filed: September 9, 2009
    Publication date: August 12, 2010
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Rieko KATAOKA, Masahiro OKITA, Toshiyuki YANO
  • Publication number: 20100202801
    Abstract: A developer carrying member is disclosed which can stably provide toners with triboelectric charges even in various environments. The developer carrying member has a substrate and a resin layer as a surface layer formed on the surface of the substrate, and the resin layer contains a thermosetting resin as a binder resin, an acrylic resin having two units having specific structures, and conductive particles.
    Type: Application
    Filed: April 20, 2010
    Publication date: August 12, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Satoshi Otake, Masayoshi Shimamura, Yasutaka Akashi, Takuma Matsuda, Minoru Ito, Kazuhito Wakabayashi
  • Publication number: 20100196818
    Abstract: Employment of a carrier core material for an electrophotographic developer containing 0.8 to 5% by weight of Mg, 0.1 to 1.5% by weight of Ti, 60 to 70% by weight of Fe and 0.2 to 2.5% by weight of Sr and having an amount of Sr dissolved with a pH4 standard solution of 80 to 1000 ppm, a carrier using the core material and a process for producing them, and an electrophotographic developer using the carrier.
    Type: Application
    Filed: January 12, 2010
    Publication date: August 5, 2010
    Applicant: POWDERTECH CO., LTD.
    Inventors: Takashi KOJIMA, Toru IWATA, Koji AGA
  • Patent number: 7767370
    Abstract: A two-component developer containing a magenta toner and a magnetic carrier, wherein the magenta toner has the characteristics: (i) when the concentration of the magenta toner in a solution of the magenta toner in chloroform is represented by Cm (mg/ml) and the absorbance of the solution at a wavelength of 538 nm is represented by A538, a relationship between Cm and A538 satisfies the relationship of 2.00<A538/Cm<6.55; (ii) the lightness L* and chroma C* of the magenta toner determined in a powder state satisfy the relationships of 35?L*?45 and 60?C*?72; and (iii) the absolute value for the triboelectric charge quantity of the magenta toner measured by a two-component method using the magenta toner and the magnetic carrier is 50 mC/kg or more and 120 mC/kg or less.
    Type: Grant
    Filed: July 29, 2008
    Date of Patent: August 3, 2010
    Assignee: Canon Kabushiki Kaisha
    Inventors: Koh Ishigami, Kazuo Terauchi, Noriyoshi Umeda, Tetsuya Ida, Naoki Okamoto, Yojiro Hotta, Yoshinobu Baba, Takayuki Itakura, Takeshi Yamamoto, Manami Haraguchi, Kenta Kubo
  • Patent number: 7736827
    Abstract: In a method for recycling a double component developer that contains a carrier and a toner used for an image forming device such as office automation equipment, an economic value of recycling is increased, thereby allowing a company to carry out an active and sustainable environmental activity. Material components of a carrier are completely utilized, so that a process of removing and disposing part of components of the carrier, which is present in the conventional technology of a carrier recycling, is omitted from a recycling system, and in consequence, a cost of recycling is minimized. Furthermore, as well as a subject of the recycling, i.e. a carrier itself, a more valuable material, i.e. a platinum group metal, is utilized for the recycling.
    Type: Grant
    Filed: August 18, 2006
    Date of Patent: June 15, 2010
    Assignees: Ricoh Company, Limited, Shinko-Frex Inc.
    Inventors: Yoshihiro Morii, Hiroyuki Matsuura, Takeshi Sugimoto, Kazuma Torii
  • Publication number: 20100075244
    Abstract: To provide a carrier for electrophotographic developer, capable of realizing a high image quality and full colorization and reducing carrier scattering, and a manufacturing method of the same, and an electrophotographic developer containing the carrier. A carrier core material for electrophotographic developer, with a general formula expressed by MgxMn(1-x)FeyO4 (where 0<x<1, and 1.6?y?2.4), wherein a half-value width B of a peak having a maximum intensity in a powder XRD pattern satisfies B?0.180 (degree), is manufactured and from this carrier core material for electrophotographic developer, the carrier for electrophotographic developer and the electrophotographic developer are manufactured.
    Type: Application
    Filed: April 9, 2008
    Publication date: March 25, 2010
    Applicants: DOWA ELECTRONICS MATERIALS CO., LTD., DOWA IP CREATION CO., LTD.
    Inventors: Tomoya Yamada, Takashi Fujiwara, Ryusuke Nakao, Yukihiro Matuda, Tomokazu Mouri
  • Publication number: 20100068645
    Abstract: A carrier for developing an electrostatic latent image which includes a core material and a resin coating layer provided on the core material. The resin coating layer includes a resin and a particulate tin oxide, and the surface of the particulate tin oxide is coated with carbon.
    Type: Application
    Filed: September 17, 2009
    Publication date: March 18, 2010
    Inventors: Hitoshi Iwatsuki, Kimitoshi Yamaguchi, Minoru Masuda, Yutaka Takahashi, Koichi Sakata
  • Publication number: 20100040969
    Abstract: A toner composition and a method of making a toner composition wherein toner particles having an average size in the range of 1-25 ?m may be mixed with silica particles and alumina particles surface treated with an inorganic/organic compound. The silica particles may have a primary particle size in the range of 2 nm to 20 nm and may be present in the range of 0.01% to 3.0% by weight of the toner composition. The alumina particles surface treated with an inorganic/organic compound may be present in the range of 0.01% to 1.0% by weight of the toner composition.
    Type: Application
    Filed: August 12, 2008
    Publication date: February 18, 2010
    Inventors: Ligia Aura Bejat, Joseph Edward Johnson, Rick Owen Jones, Bryan Patrick Livengood, Kasturi Rangan Srinivasan, Devon Jean Vaccaro Strain
  • Publication number: 20100035174
    Abstract: To provide a carrier for an electrophotographic developer in which high image quality and full colorization are possible while carrier scattering is reduced, and a method for producing the carrier, and an electrophotographic developer including the carrier. A carrier core material for an electrophotographic developer is produced so that the half-value width B of a peak having a maximum intensity in an XRD pattern satisfies B?0.160 (degree). A carrier for an electrophotographic developer and an electrophotographic developer are produced from the carrier core material for an electrophotographic developer.
    Type: Application
    Filed: March 21, 2008
    Publication date: February 11, 2010
    Applicants: Dowa Electronics Materials Co., Ltd., Dowa IP Creation Co., Ltd.
    Inventors: Tomoya Yamada, Takashi Fujiwara, Ryusuke Nakao, Yukihiro Matuda, Tomokazu Mouri
  • Patent number: 7649053
    Abstract: A toner binder for electrophotography excellent in low temperature fixing properties and anti-hot offset properties comprising styrene (co)polymer(s) (A) comprising a modified styrene (co)polymer modified by unsaturated dicarboxylic acids of C4 to C30, ester-forming derivatives thereof, (meth)acrylic acid, or alkyl (meth)acrylates (alkyl group of C1 to C24); said modified styrene (co)polymer containing constituent units derived from a monomer used in the modification is 0.1 to 9 wt %, and a toner using the toner binder. The (co)polymer(s) (A) includes a species that shows at least one GPC peak each in the regions of the molecular weight of 2,000 to 20,000 and 50,000 to 5 million.
    Type: Grant
    Filed: February 25, 2003
    Date of Patent: January 19, 2010
    Assignee: Sanyo Chemical Industries, Ltd
    Inventor: Tomohisa Kato
  • Publication number: 20090311620
    Abstract: A carrier has a thermosetting silicone resin layer formed of a core particle and a thermosetting silicone resin on the surface of the core particle, and the thermosetting silicone resin layer is formed by subjecting a thermosetting silicone resin to a thermosetting treatment at a temperature lower than the melting point of a charge control agent contained in the thermosetting silicone resin layer, and includes an inner region which contains a positively chargeable charge control agent and an outer region which does not contain any positively chargeable charge control agent. The two-component developer containing the carrier as described above is charged into a developing device in an image forming apparatus to form an image.
    Type: Application
    Filed: June 11, 2009
    Publication date: December 17, 2009
    Inventors: Kanako Hirata, Kazuki Takatsuka, Toru Nishikawa
  • Patent number: 7632620
    Abstract: A carrier comprised of a core, and thereover a polymer coating containing a first polymer and a silicone resin, and which resin possesses an average diameter of from about 300 to about 3,000 nanometers.
    Type: Grant
    Filed: January 28, 2005
    Date of Patent: December 15, 2009
    Assignee: Xerox Corporation
    Inventors: Brian S. Giannetto, Thomas J. Budny, Brian E. Moore, Zhaoyi M. Masucci, Samir Kumar, Bernard A. Kelly, Lloyd D. Spencer
  • Publication number: 20090297974
    Abstract: A carrier for an electrophotographic developer, in which a carrier core material surface is coated with a mixed resin of a fluorine resin selected from a tetrafluoroethylene-hexafluoropropylene copolymer or a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, and a polyamide imide resin, wherein the mixed resin includes a surfactant and a charge control agent, and the mixed resin has a perfluorooctanoic acid content of 100 ppm or less and an electrophotographic developer using this carrier.
    Type: Application
    Filed: March 25, 2009
    Publication date: December 3, 2009
    Applicant: Powdertech Co., Ltd.
    Inventors: Takashi Kojima, Tetsuya Uemura, Tsuyoshi Itagoshi
  • Patent number: 7622235
    Abstract: Coated carrier particles are provided for use in developer compositions for electrophotographic imaging. The coated carrier particles include a carrier core and a resin coating that includes first and second polymer components. The coated carrier particles exhibit stable triboelectric charging during aging, decreased coating hardness, higher coating coverage, and an improved resilience to toner impaction.
    Type: Grant
    Filed: August 29, 2008
    Date of Patent: November 24, 2009
    Assignee: Xerox Corporation
    Inventors: Deepak R. Maniar, Thomas C. Dombroski, Victor Berko-Boateng, Christopher M. Pattison, Angela Schnuerch
  • Publication number: 20090258311
    Abstract: The present invention provides a carrier core material for use in the production of an electrophotographic developer which, even when applied, for example, to MFPs (multifunction printers), can realize stable, high-quality and high-speed development, and has a prolonged replacing life of magnetic carriers, and a method of manufacturing the same, a magnetic carrier including the carrier core material, and an electrophotographic developer manufactured from the magnetic carrier. An electrophotographic development carrier is prepared by adding resin particles, a binder, a dispersant, a wetting agent, and water to a raw material powder, wet pulverizing the mixture, drying the pulverized product to give granulated powder, calcinatng the granulated powder, and then sintering the granulated powder to prepare a carrier core material having an internally hollow structure, and coating the carrier core material with a resin.
    Type: Application
    Filed: September 25, 2006
    Publication date: October 15, 2009
    Inventors: Ryusuke Nakao, Takeshi Kawauchi
  • Patent number: 7601473
    Abstract: The invention relates to a developer for developing electrostatic images. The developer includes magnetic carrier particles at a loading of from 60 to 99 weight percent of the developer. Toner particles are at a loading of 1 to 40 weight percent of the developer. The toner particles include a resin core particle having an outer surface and 0.05 to 5 weight percent a first metal oxide powder is substantially fixed to the outer surface. The toner particles further include 0.05 to 2 weight percent of a second metal oxide powder that is substantially free to transfer between outer surface of the toner particles and an outer surface of the magnetic carrier surface.
    Type: Grant
    Filed: June 23, 2006
    Date of Patent: October 13, 2009
    Assignee: Eastman Kodak Company
    Inventors: Kevin D. Lofftus, Satyanarayan Srinivsan, David D. Putnam, Peter S. Alexandrovich
  • Publication number: 20090246670
    Abstract: Carrier particles for forming a wiring circuit pattern by an electrophotographic developing method which are used for directly forming a circuit shape on an insulating layer, with any of a metal powder, an inorganic compound powder, or a mixed raw material powder thereof used as a toner powder for forming a circuit, the toner powder for forming a circuit being adhered to a surface of the carrier particles by electrostatic force and then transported to a surface of the insulating layer, wherein the carrier particles include a resin coated layer of an acrylic resin composition containing an amino-group-containing polymer on the surface of the carrier core material particles, the coating amount of the acrylic resin composition is 0.3 to 3.0% by weight based on a carrier core material weight of 100% by weight, and a shape factor SF-1 of the carrier core material particles is 100 to 110.
    Type: Application
    Filed: March 6, 2009
    Publication date: October 1, 2009
    Applicant: POWDERTECH CO., LTD.
    Inventors: Koji AGA, Atsushi NII
  • Publication number: 20090226838
    Abstract: There are provided a carrier which enables stable charging of toner and formation of a stable, high-definition and high-quality image which has very few image defects such as a fog, as well as a developer, a developing apparatus, and an image forming apparatus. A carrier is obtained by including a carrier core and a coating layer with which a surface of the carrier core is coated, the coating layer being obtained by curing a resin composition for coating that includes a crosslinked silicone-modified acrylic resin containing a macromonomer represented by the following general formula (1). A developer is obtained by such a carrier and a toner.
    Type: Application
    Filed: March 6, 2009
    Publication date: September 10, 2009
    Inventor: Takanori KAMOTO
  • Publication number: 20090226218
    Abstract: The present invention provides a carrier for a two-component electrophotographic developer, comprising a core particle and a thermoset silicone resin layer coated thereon, wherein said layer comprises a charge control agent and is formed by heat-treatment at a temperature below the melting point of said charge control agent.
    Type: Application
    Filed: February 26, 2009
    Publication date: September 10, 2009
    Inventors: Kazuki Takatsuka, Tatsuo Imafuku, Takahiro Bito, Takeshi Satoh, Masaki Ueji
  • Patent number: 7574164
    Abstract: An electrophotographic apparatus includes: a photoconductor; and two developing rollers facing the photoconductor. A developer fed out from between the two developing rollers is supplied to the photoconductor by the two developing rollers to form a toner image on the photoconductor. The developer includes a carrier having a volume-average particle size smaller than 70 ?m and a volume resistivity not lower than 106 ?·cm. A volume ratio of the carrier in a facing portion between the photoconductor and the developing rollers is not lower than 30% and not higher than 46%.
    Type: Grant
    Filed: September 23, 2005
    Date of Patent: August 11, 2009
    Assignee: Ricoh Company Ltd.
    Inventors: Hisao Okada, Hiroyuki Mabuchi, Teruaki Mitsuya, Tsuneaki Kawanishi, Akio Tsujita
  • Publication number: 20090197194
    Abstract: There are adopted: a carrier core material for an electrophotographic developer, including Mg, Ti and Fe as main components, and containing Fe, Mg and Ti in contents of 52 to 66% by weight, 3 to 12% by weight and 0.2 to 12% by weight, respectively; an electrophotographic developer carrier prepared by coating with a resin the surface of the carrier core material; and an electrophotographic developer using the carrier.
    Type: Application
    Filed: January 30, 2009
    Publication date: August 6, 2009
    Applicant: POWDERTECH CO., LTD.
    Inventors: Koji Aga, Issei Shinmura, Tetsuya Igarashi
  • Patent number: 7570904
    Abstract: In the image forming apparatus by: visualizing an electrostatic latent image formed on an electrostatic charge carrying member; transferring a toner image, which is thus visualized, to a recording medium, or to a recording medium through an intermediate transfer material; and fixing the toner image, which is thus transferred to the recording medium, to obtain a recorded image, the toner includes at least a fixing resin, a colorant, a releasing agent, and an external additive, the toner has an average particle diameter in a range of from 4 to 12 ?m and including no particle having a diameter of 45 ?m or more, a ratio of a toner adhesion amount in a character part to a toner adhesion amount in a solid image part upon printing is more than 0.5 and less than 4, and the toner adhesion amount in a character part is 1.6 mg/cm2 or less.
    Type: Grant
    Filed: May 26, 2005
    Date of Patent: August 4, 2009
    Assignee: Ricoh Printing Systems, Ltd.
    Inventors: Shigenori Yaguchi, Junji Kobayashi, Hirobumi Ouchi, Tomonari Hokkyo
  • Publication number: 20090170022
    Abstract: There are adopted: an electrophotographic developer carrier that includes on the surface of a carrier core material a coating resin including a silicone resin containing a fluorine silane coupling agent, has an intensity ratio (F/Si), measured with fluorescent X-ray, between the fluorine atom and the silicon atom present on the carrier surface of 1.4×10?3 to 2.0×10?3, and has an intensity ratio (F/Fe), measured with fluorescent X-ray, between the fluorine atom and the iron atom present on the carrier surface of 2.3×10?5 to 3.5×10?5; and an electrophotographic developer using the carrier.
    Type: Application
    Filed: December 23, 2008
    Publication date: July 2, 2009
    Applicant: POWDERTECH CO., LTD.
    Inventors: Takashi KOJIMA, Tetsuya UEMURA, Tsuyoshi ITAGOSHI
  • Patent number: 7553598
    Abstract: A carrier contains a core; and a cover layer located overlying the core, wherein the cover layer comprises a binder resin, a first particulate material and a second particulate material, wherein the following relationships are satisfied: 1<(D1/h)<10, and 0.001<(D2/h)<1, wherein D1(?m) represents a volume average particle diameter of the first particulate material, D2(?m) represents a volume average particle diameter of the second particulate material, and h (?m) represents a thickness of the cover layer, and wherein the second particulate material has a volume resistivity of not greater than 1.0×1012 ?·cm.
    Type: Grant
    Filed: March 20, 2006
    Date of Patent: June 30, 2009
    Assignee: Ricoh Company, Limited
    Inventors: Kousuke Suzuki, Tomio Kondoh, Shinichiro Yagi, Hitoshi Iwatsuki
  • Publication number: 20090142688
    Abstract: A dry powder carrier coating composition that may be used to coat carrier particles that imparts desired triboelectric charging characteristics and conductivity values to make the carrier particles more insulative. In embodiments, the coating composition includes a styrene acrylate copolymer.
    Type: Application
    Filed: February 5, 2008
    Publication date: June 4, 2009
    Applicant: XEROX CORPORATION
    Inventors: Brian S. Giannetto, Christopher M. Pattison, Thomas C. Dombroski, Brian E. Moore, Thomas J. Budny, Padam K. Angra, Zhaoyi M. Masucci, Bernard A. Kelly
  • Patent number: 7527908
    Abstract: A carrier contains a core material; and a coated film containing a binder resin, and a particulate material, the coated film covering the core material, wherein a ratio (D/h) of an average particle diameter (D) of the particulate material to an average thickness (h) of the coated film is from 0.01 to 1, and wherein the carrier has concavities and convexities on the surface of the carrier, the concavities and convexities having a difference of elevation of from 0.05 to 2.0 ?m.
    Type: Grant
    Filed: April 6, 2006
    Date of Patent: May 5, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Hitoshi Iwatsuki, Tomio Kondou, Shinichiro Yagi, Kousuke Suzuki
  • Publication number: 20090053643
    Abstract: The present invention provides a magnetic mono-component toner which can suppress a selection development on a latent image carrier and can maintain favorable image properties for a long period by using a toner having the coarse powder distribution (S) within a given range in a jumping developing method and an image forming method which uses the toner. In the toner used in the jumping developing method which develops an electrostatic latent image formed on a latent image carrier using a developer carrier, the toner includes toner particles which contain at least a binding resin and a magnetic powder, and the coarse powder distribution (S) of the toner particles satisfies a following formula (1).
    Type: Application
    Filed: October 9, 2008
    Publication date: February 26, 2009
    Inventor: Hideaki Kawata
  • Publication number: 20090047594
    Abstract: A developer according to the present invention is arranged such that the composition of particulate metal oxide added as an external additive to a toner surface and the composition of particulate metal oxide added to a resin layer covering a carrier surface are identical to each other, so that the amount of frictional charge that is generated between the toner and the external additive is made larger than the amount of frictional charge that is generated between the external additive and the carrier surface. With this, the external additive is prevented from migrating from the toner surface onto the carrier surface. This makes it possible to prevent the external additive from migrating from the toner surface onto the carrier surface, and thereby to remedy (i) defects in charge and fluidity and (ii) secondary failures, i.e., defects in development that are caused by deterioration in performance of the developer due to the defects in charge and fluidity.
    Type: Application
    Filed: January 11, 2008
    Publication date: February 19, 2009
    Applicant: Sharp Kabushiki Kaisha
    Inventor: Hiroyuki Hirakawa
  • Patent number: 7485400
    Abstract: A developer includes a carrier and a toner, wherein the toner contains toner particles of at least one binder, at least one colorant, and external additives, wherein the developer has a trimmer clogging value in relation to toner triboelectric charge and toner cohesion expressed according to the equation (?0.80+0.039×(% toner cohesion)+0.026×(toner triboelectric charge) (?C/g)) of less than or equal to about 3.2.
    Type: Grant
    Filed: April 5, 2006
    Date of Patent: February 3, 2009
    Assignee: Xerox Corporation
    Inventors: Richard P. N. Veregin, Cuong Vong, Vladislav Skorokhod, Jackie B. Parker, David J. Sanders
  • Publication number: 20090029281
    Abstract: To provide a two-component developer and an image forming device which are excellent in stability of image density in formed images even when image formation is continued for a long time, by controlling non-electrostatic adhesion force between toner particle and a carrier or developing roll and maintaining the charge property of toner particle effectively. A two-component developer in which the surface of a toner particle and the surface of a carrier are each covered with a fluorine compound, wherein a ratio represented by (A2/A1) is adjusted to a value within a range of from 0.1 to 0.5 where the coverage with the fluorine compound on the surface of the toner particle is A1 and the coverage with the fluorine compound on the surface of the carrier is (A2).
    Type: Application
    Filed: June 30, 2008
    Publication date: January 29, 2009
    Applicant: KYOCERA MITA CORPORATION
    Inventor: Seiji Kikushima
  • Patent number: RE41652
    Abstract: A toner and process for making the toner wherein each combined resin and colorant particle has an average size less than about 10 microns and wherein the surface additive particles averaging less than about 40 nanometers in size average greater than two (2) percent of the combined weight of resin and colorant in the toner and wherein the Additive Adhesion Force Distribution percent value after 12 kilojoules of energy is greater than 40 percent.
    Type: Grant
    Filed: June 4, 2009
    Date of Patent: September 7, 2010
    Assignee: Xerox Corporation
    Inventor: James M. Proper