Patents Examined by Christopher D. Rodee
  • Patent number: 6156469
    Abstract: A developing agent exhibiting satisfactory negative charging characteristics can be obtained by allowing the developing agent to contain a toner, which contains a predetermined 2:1 type metal complex salt dye as a charge control agent or as a coloring agent, and carrier particles represented by general formula (MO).sub.X (Fe.sub.2 O.sub.3).sub.Y, obtained by using a kneaded mixture containing predetermined 2:1 type metal complex salt compound particles and a binder resin to have an average particle diameter of 0.2 .mu.m or less, or by allowing a binder resin to contain in advance a low molecular weight wax in manufacturing a developing agent containing a predetermined 2:1 type metal complex salt compound.
    Type: Grant
    Filed: September 17, 1998
    Date of Patent: December 5, 2000
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Shuitsu Sato
  • Patent number: 6156466
    Abstract: The present invention relates to photoconductors which exhibit excellent electrical properties which are not appreciably affected by environmental changes or by repeated use. Having excellent durability during repeated printing, these photoconductors can be used to obtain large quantities of high-quality output images.The photoconductor according to the invention includes a conductive substrate and a photoconductive film on the conductive substrate. The photoconductive film includes a plurality of charge generation and transport layers, wherein each layer contains a phthalocyanine compound described in the specification by chemical formula (I) as a charge generation agent and a charge transport agent dispersed or dissolved into a binder. The concentration of the charge generation agent in an upper layer is higher than in a lower layer.
    Type: Grant
    Filed: July 8, 1998
    Date of Patent: December 5, 2000
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Shinichi Tamura, Tadashi Mimura, Yoji Yamada, Tadashi Asakawa, Hiroshi Kimura
  • Patent number: 6153345
    Abstract: Disclosed is a color toner for developing an electrostatic latent image, wherein the colorant comprises a metal complex dye represented by Formula: ##STR1## wherein X is represented by Formula 2. ##STR2## The definitions are specified in the specification.
    Type: Grant
    Filed: February 11, 1999
    Date of Patent: November 28, 2000
    Assignee: Konica Corporation
    Inventors: Kaori Soeda, Meizo Shirose
  • Patent number: 6150064
    Abstract: A photoconductor for electrophotography includes a photoconductive layer that contains titanyloxyphthalocyanine as a charge generation agent. The concentration of SO.sub.4.sup.2- with respect to the concentration of titanyloxyphthalocyanine is adjusted to be less than or equal to 500 ppm. The photoconductor may be of either a monolayer or a laminate construction. In the case of a laminate type photoconductor, the titanyloxyphthalocyanine is incorporated into the charge generation layer.
    Type: Grant
    Filed: April 16, 1998
    Date of Patent: November 21, 2000
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Kazumi Egota, Yoichi Nakamura, Masahide Takano, Hideki Kina, Akira Ootani
  • Patent number: 6150065
    Abstract: Disclosed is a charge transfer material which is highly soluble in a binder resin, does not precipitates crystals and produces no pinhole and also disclosed is an electrophotographic photoreceptor comprising the charge transfer material which comprises a butadiene compound represented by the formula (I): ##STR1## wherein R.sup.1 and R.sup.2, which may be the same or different, respectively represent a lower alkyl group having 1-4 carbon atoms or a phenyl group or benzyl group which may have a substituent and R.sup.3, R.sup.4 and R.sup.5, which may be the same or different, respectively represent a hydrogen atom, a halogen atom, a lower alkyl group, a lower alkoxy group having 1-4 carbon atoms or a halogen atom; and a butadiene compound represented by the general formula (II): ##STR2## wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.
    Type: Grant
    Filed: April 5, 1999
    Date of Patent: November 21, 2000
    Assignee: Takasago International Corporation
    Inventors: Tohru Kobayashi, Yoko Aoki, Mamoru Yamada, Yoshimasa Matsushima, Hiroshi Sugiyama, Toshimitsu Hagiwara, Hajime Suzuki
  • Patent number: 6146804
    Abstract: (1) Electrophotographic liquid developer comprising electrically insulating medium liquid and toner dispersed in the medium liquid, wherein the toner has a melt viscosity (.eta.) in a range from 2.times.10.sup.2 poises to 1.times.10.sup.5 poises at 100.degree. C. in a dry state, and has a glass transition temperature of 20.degree. C. or more.(2) Electrophotographic liquid developer comprising electrically insulating medium liquid and toner dispersed in the medium liquid, wherein the toner contains binder resin exhibiting at least one peak in each of ranges of a molecular weight lower than 5000 and of a molecular weight of 5000 or more when detected by a gel permeation chromatography (GPC).
    Type: Grant
    Filed: December 23, 1999
    Date of Patent: November 14, 2000
    Assignee: Minolta Co., Ltd.
    Inventors: Hidetoshi Miyamoto, Toshimitsu Fujiwara, Shuji Iino, Masaharu Kanazawa, Seishi Ojima
  • Patent number: 6140003
    Abstract: A toner composition comprised of resin particles, pigment and a charge enhancing additive comprised of a polymer or said resin particles with a charge enhancing moiety chemically attached thereto, and which charge additive is of the formula ##STR1## wherein X is an alkaline, an alkaline earth metal, a metal, or the ammonium cation H.sub.4 N+, R".sub.4 N+ wherein R" is an alkyl or arylalkyl group; R is alkylene, cyclohexyl, bisphenol, bis(alkyloxyl), or oxyalkylene; and R' is an alkylene, an arylene, cycloalkylene group.
    Type: Grant
    Filed: April 1, 1994
    Date of Patent: October 31, 2000
    Assignee: Xerox Corporation
    Inventors: Guerino G. Sacripante, Richard P. N. Veregin
  • Patent number: 6139999
    Abstract: An electrophotographic imaging member includingat least one photographic imaging layer anda partially electrically conductive overcoat layer includingfinely divided charge injection enabling particles dispersed ina charge transporting continuous matrix including a cross linked polyamide, charge transport molecules and oxidized charge transport molecules, the continuous matrix being formed from a solution selected from the group includinga first solution includingcrosslinkable alcohol soluble polyamide containing methoxy methyl groups attached to amide nitrogen atoms,an acid having a pK.sub.
    Type: Grant
    Filed: October 28, 1999
    Date of Patent: October 31, 2000
    Assignee: Xerox Corporation
    Inventors: Timothy J. Fuller, Damodar M. Pai, John F. Yanus, Paul J. DeFeo, Anthony T. Ward, Dale S. Renfer, Harold F. Hammond, Merlin E. Scharfe, Markus R. Silvestri, William W. Limburg
  • Patent number: 6139997
    Abstract: An electrophotographic photosensitive member is formed of a support, and a photosensitive layer disposed on the support. The photosensitive layer is characterized by containing an azo pigment having an organic group represented by formula (1) below: ##STR1## wherein X.sub.1, Z.sub.1, k.sub.1, B, A, R.sub.1 and R.sub.2 are defined in the text. The group of the formula (1) may provide at least one of up to 4 azo-substituents of the azo pigment having an entire structure represented byAr.paren open-st.N.dbd.N--Cp) 1-4,wherein Ar denotes an aromatic or heterocyclic core unit, Cp denotes a coupler residue group, and --(N.dbd.N--Cp) denotes such an azo-substituent. The photosensitive member can exhibit good electro-photographic performances including high and stable sensitivity on repetitive use.
    Type: Grant
    Filed: March 8, 1999
    Date of Patent: October 31, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masato Tanaka, Kouichi Nakata
  • Patent number: 6140002
    Abstract: A binder resin for toners which comprises a styrene-acrylic resin comprising a high molecular weight polymer component and a low molecular weight polymer component, wherein, in terms of the molecular weight distribution as measured by gel permeation chromatography, the high molecular weight polymer component has a first peak in the region of molecular weight 5.times.10.sup.4 to 8.times.10.sup.5 and at least 2 peaks and/or shoulders at the high molecular weight side above the molecular weight of the first peak, as well as a toner containing the resin.
    Type: Grant
    Filed: December 19, 1997
    Date of Patent: October 31, 2000
    Assignee: Mitsubishi Rayon Co., Ltd.
    Inventors: Koji Shimizu, Motoshi Inagaki, Yoko Harada, Noriyuki Tajiri
  • Patent number: 6136485
    Abstract: The object of the invention is to provide a highly characteristic and lesser defective image using an electrophotographic photoreceptor which can be produced with a better coating property and which is highly sensitive and hardly loses the electrostatic stability during repeated use. A water-soluble or water/alcohol-soluble polyvinyl acetal and an inorganic pigment are involved in an underlayer provided between a conductive support and a photoconductive layer. Particularly, it is favorable to use titanium oxide as the inorganic pigment, make the ratio of polyvinyl acetal/titanium oxide 1/9-9/1 by weight, make the underlayer 0.5-5 .mu.
    Type: Grant
    Filed: November 9, 1998
    Date of Patent: October 24, 2000
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Kazuya Ishida, Satoshi Katayama, Takahiro Teramoto, Akihiko Kawahara, Kazushige Morita, Tomoko Kanazawa
  • Patent number: 6136410
    Abstract: To enable high density mass storage recording, for an upper magnetic layer, the length of a major axis of metallic magnetic powder, the type of binder, the hardness and particle size of abrasive powder, the condition of kneading, surface roughness and thickness are regulated, for a lower nonmagnetic layer, the length of a major axis of nonmagnetic powder, the ratio of the length of a major axis to that of a minor axis and the type of binder are regulated and further, a method of forming the upper magnetic layer and the lower nonmagnetic layer, the thickness of a nonmagnetic base material and Young's modulus are regulated.
    Type: Grant
    Filed: October 3, 1996
    Date of Patent: October 24, 2000
    Assignee: Sony Corporation
    Inventors: Kazuhiro Okamoto, Takao Kudo, Yuichi Sasaki, Taro Ohmura
  • Patent number: 6132912
    Abstract: A photoconductive imaging member comprised of a supporting substrate, a layer (1) thereover, a photogenerating layer and a charge transport layer, and wherein said layer (1) is generated from a mixture of a polyhydroxyalkylacrylate, and an amino alkyltrialkoxysilane.
    Type: Grant
    Filed: May 27, 1999
    Date of Patent: October 17, 2000
    Assignee: Xerox Corporation
    Inventors: Timothy J. Fuller, Damodar M. Pai, John F. Yanus, Markus R. Silvestri, Huoy-Jen Yuh, John S. Chambers, Harold F. Hammond, Susan M. Vandusen, Dennis J. Prosser, Kathleen M. Carmichael, Robert C. U. Yu, Neil S. Patterson
  • Patent number: 6132924
    Abstract: A process for the preparation of toner comprising mixing a colorant, a latex, and two coagulants, followed by aggregation and coalescence.
    Type: Grant
    Filed: October 15, 1998
    Date of Patent: October 17, 2000
    Assignee: Xerox Corporation
    Inventors: Raj D. Patel, Michael A. Hopper, Richard P. N. Veregin
  • Patent number: 6130021
    Abstract: A process involving the mixing of a latex emulsion containing resin and a surfactant with a colorant dispersion containing a nonionic surfactant, and a polymeric additive and adjusting the resulting mixture pH to less than about 4 by the addition of an acid and thereafter heating at a temperature below about, or equal to about the glass transition temperature (Tg) of the latex resin, subsequently heating at a temperature above about, or about equal to the Tg of the latex resin, cooling to about room temperature, and isolating the toner product.
    Type: Grant
    Filed: April 13, 1998
    Date of Patent: October 10, 2000
    Assignee: Xerox Corporation
    Inventors: Raj D. Patel, Michael A. Hopper
  • Patent number: 6130019
    Abstract: The present invention relates to a binder carrier comprising at least magnetic particles and a binder resin. The binder resin contains a thermoplastic silicone-modified acrylic resin which is a copolymer of a polydiorgano-siloxane macromer having an acrylic functional group and a radical-polymerizable organic monomer.The binder carrier of the present invention a long-life binder carrier which eliminates the possibility of carrier deterioration due to toner components, such as a charge-controlling agent and an after-treatment agent, and which is less liable to deteriorate in its chargeability.
    Type: Grant
    Filed: December 1, 1998
    Date of Patent: October 10, 2000
    Assignee: Minolta Co., Ltd.
    Inventors: Tomoharu Nishikawa, Makoto Kobayashi, Koichi Takenaka, Hideaki Yasunaga, Hiroyuki Fukuda, Haruhiko Furukawa, Hiroshi Ueki, Yoshitsugu Morita
  • Patent number: 6127077
    Abstract: A photoreceptor having a substrate, including: (a) a charge generating layer; (b) a first charge transport layer having a first charge carrier mobility value; and (c) a second charge transport layer having a second charge carrier mobility value, wherein the first charge transport layer is closer to the charge generating layer than the second charge transport layer and the second charge transport layer is contiguous to the first charge transport layer, wherein the second charge carrier mobility value is higher than the first charge carrier mobility value.
    Type: Grant
    Filed: September 14, 1998
    Date of Patent: October 3, 2000
    Assignee: Xerox Corporation
    Inventors: Damodar M. Pai, Chu-Heng Liu, John F. Yanus, Timothy J. Fuller, Markus R. Silvestri
  • Patent number: 6124067
    Abstract: A magnetic carrier constituting a two-component developer for use in an electrophotographic image forming method is formed of a carrier core comprising a first resin and magnetic fine particles dispersed in the first resin, and a second resin surface-coating the carrier core. (a) The magnetic carrier has a true specific gravity of 2.5-4.5, a magnetization .sigma..sub.1000 as measured in a magnetic field of 1000.times.(10.sup.3 /4.pi.).multidot.A/m (1000 oersted) of 15-60 Am.sup.2 /kg (emu/g), a residual magnetization .sigma..sub.r of 0.1-20 Am.sup.2 /kg (emu/g) and a resistivity of 5.times.10.sup.11 -5.times.10.sup.15 ohm.cm. (b) The first resin has a polymer chain including a methylene unit (--CH.sub.2 --). (c) The second resin has at least a fluoro-alkyl unit, a methylene unit (--CH.sub.2 --) and an ester unit.
    Type: Grant
    Filed: July 22, 1999
    Date of Patent: September 26, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yushi Mikuriya, Kenji Okado, Kazumi Yoshizaki
  • Patent number: 6120961
    Abstract: A toner for developing an electrostatic image includes a binder resin, a colorant and a wax. The toner shows heat-absorption characteristics represented by a DSC heat-absorption curve obtained on temperature increase in a temperature range of 30-150.degree. C. by a differential scanning colorimeter (DSC). The DSC heat-absorption curve shows a maximum heat-absorption peak (P1) in a temperature range of 70-90.degree. C. The DSC curve also provides a differential curve showing a first maximum (Max1) on a lowest temperature side at a temperature (T1) of 50-65.degree. C., showing a second maximum (Max2) on a next lowest temperature side at a temperature (T2) of 65-85.degree. C., and showing a minimum (Min1) on a highest temperature side at a temperature (T3) of at least 95.degree. C. Because of the DSC heat-absorption characteristics, the toner exhibits excellent fixability (including anti-offset characteristic) over a wide temperature range and excellent continuous image forming characteristic.
    Type: Grant
    Filed: September 26, 1997
    Date of Patent: September 19, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hirohide Tanikawa, Masami Fujimoto, Tsutomu Onuma, Hiroyuki Fujikawa
  • Patent number: 6120916
    Abstract: A composite magnetic material showing reduced losses and reduced permeability when it is subjected to a magnetic field at frequencies below approximately 100 MHz. It comprises magnetic particles in the form of wafers dispersed in a dielectric binder. The polycrystalline magnetic ceramic wafers are oriented so that their main faces are substantially parallel to the magnetic field.Application especially to cores of inductors or transformers.
    Type: Grant
    Filed: September 9, 1996
    Date of Patent: September 19, 2000
    Assignee: Thomson-CSF
    Inventors: Jean-Pierre Delvinquier, Richard Lebourgeois, Michel Pate, Claude Rohart