Patents Examined by Roland Martin
  • Patent number: 6190813
    Abstract: With the object of providing an imaging method that eliminates the occurrence of transfer ghosts, saves space and lowers costs, and by which image density irregularities do not arise, an imaging method utilized in a reverse-transfer system is disclosed. The reverse-transfer system is provided with, in order going round a photosensitive conductor 1, at least a main-charging stage 2, an exposure stage 3, a reverse-developing stage 4, a transfer stage 5, a separation stage 6 and a charge-stripping stage 7. The separation stage 6 applies a separation shift-bias voltage to the photosensitive conductor 1 surface. The separation shift-bias voltage is 1 kV or more, and is of the same polarity as that of the main-charging voltage that the main-charging stage 2 applies to the photosensitive conductor 1 surface. Making the separation shift-bias voltage 1 kV or more prevents transfer ghosts, and obtains images with a satisfactory absence of image density irregularities.
    Type: Grant
    Filed: February 18, 2000
    Date of Patent: February 20, 2001
    Assignee: Kyocera Mita Corporation
    Inventors: Yuji Tanaka, Hirofumi Kawaguchi
  • Patent number: 6190820
    Abstract: A process for the preparation of toner by, for example (i) generating by emulsion polymerization in the presence of an initiator a first resin latex emulsion; (ii) generating in the presence of an oil soluble initiator by solution polymerization a second resin latex; (iii) mixing (ii) with a colorant; (iiib) mixing the resin latex emulsion of (i) with the resin/colorant mixture of (iii) to provide a blend of a resin and colorant; (iv) adding an aqueous inorganic cationic coagulant solution of a metal salt and optionally an organic cationic coagulant to the resin/colorant blend of (iiib); (v) heating at a temperature of from about 5° C. to about 10° C. below the resin Tg of (i), to form aggregate particles; (vi) adjusting the pH of (v) by the addition of a base; (vii) heating the aggregate particles of (v) at temperatures of from about 5° C. to about 50° C. above the Tg of the resin of (i), followed by the addition of an acid.
    Type: Grant
    Filed: September 7, 2000
    Date of Patent: February 20, 2001
    Assignee: Xerox Corporation
    Inventors: Raj D. Patel, Michael A. Hopper, Walter Mychajlowskij
  • Patent number: 6187498
    Abstract: A process including: forming a first image on a first substrate with a liquid toner comprising a resin, a colorant, a carrier liquid, and an adhesion promoting compound; transferring the image from the first substrate to a second substrate; overcoating the image on the second substrate with a transparent overcoat layer, and treating the resulting overcoated image.
    Type: Grant
    Filed: February 10, 2000
    Date of Patent: February 13, 2001
    Assignee: Xerox Corporation
    Inventors: Christopher M. Knapp, George A. Gibson, David H. Pan, John W. Spiewak
  • Patent number: 6187497
    Abstract: An electrophotographic toner comprising colored particles comprised of inorganic particles is disclosed. The inorganic particles have a saturated moisture content WL at ambient conditions of 10° C. and 20 percent RH of 1.0 to 2.0 percent by weight, a BET value of 70 to 120 m2/g, and a number average primary particle diameter of 10 to 50 nm. Further, the volume average particle diameter of said electrophotographic toner is between 3.0 and 9.0 &mgr;m.
    Type: Grant
    Filed: May 9, 2000
    Date of Patent: February 13, 2001
    Assignee: Konica Corporation
    Inventors: Sayuri Kushi, Tsuyoshi Uchida, Kenji Yamane
  • Patent number: 6187490
    Abstract: A two-component developer suitable for electrophotography is formed of a toner and a resin-coated carrier. The resin-coated carrier is formed of carrier core particles and 0.01-2.0 wt. % based on the carrier core particles of a resin coating layer coating the carrier core particles. The resin-coated carrier has an average particle size of 25-55 &mgr;m and the carrier core particles comprise a ferrite component represented by formula (I) below: (Fe2O3)a(MnO)b(MgO)c(A)d  (I), wherein A represents a mixture of SrO, CaO and Al2O3, and a, b, c and d are numbers representing mol fractions of associated components and satisfying: 0.4<a<0.6, 0.35<b<0.45, 0.07<c<0.12, 0.005<d<0.015, and a+b+c+d≦1. Because of the specific composition, the carrier core particles are provided with a smooth surface, which is reflected into a surface smoothness of the resin-coated carrier even after coated with a thin resin coating layer.
    Type: Grant
    Filed: March 15, 2000
    Date of Patent: February 13, 2001
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masaaki Taya, Takaaki Kohtaki, Yasuhiro Ichikawa
  • Patent number: 6185398
    Abstract: An electrophotographic photosensitive member is constituted by a support and a photosensitive layer disposed on the support. The electrophotographic photosensitive member has a surface layer comprising a polyester resin having a recurring unit represented by the following formula (1): wherein A1 represents a substituted or unsubstituted divalent aliphatic hydrocarbon group. The resultant surface layer is effective in improving an abrasive resistance of the photosensitive member.
    Type: Grant
    Filed: July 19, 1999
    Date of Patent: February 6, 2001
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takakazu Tanaka, Hidetoshi Hirano, Hirotoshi Uesugi
  • Patent number: 6183928
    Abstract: A toner for full color development comprising (a) a resin binder comprising a polyester; (b) a releasing agent having a melting point of 60° to 115° C.; (c) a colorant; and (d) an external additive, wherein the toner has a sum of an acid value and a hydroxyl value of from 40 to 60 KOH mg/g, a softening point of from 97° to 115° C., and a glass transition point of from 58° to 65° C., and wherein the amount of the external additive is from 1 to 5 parts by weight, based on 100 parts by weight of a toner without a treatment with the external additive. There can be provided a toner for full color development having a wide fixable region, and being excellent in the durability and the color reproducibility.
    Type: Grant
    Filed: March 30, 2000
    Date of Patent: February 6, 2001
    Assignee: Kao Corporation
    Inventors: Shinichi Sata, Eiji Shirai
  • Patent number: 6183924
    Abstract: The present invention provides a novel developer comprising a spherically particulate toner having a volume-average particle diameter of from about 1 to 6 &mgr;m for use in the development of electrostatic image in electrophotographic copying machines or printers having a colorant content of from 8 to 20% by weight, if the colorant is carbon black, or from 3 to 20% by weight, if the colorant is an organic pigment, based on the sum of the weight of binder resin and colorant and a resin-coated carrier having a volume-average particle diameter of from 20 to 150 &mgr;m. The present invention also provides a suitable polymerization or emulsification process for the preparation of a particulate toner to be incorporated in the developer. The use of the electrostatic image developer makes it possible to not only improve the quality of images provided by copying machines or printers but also realize drastic reduction of the amount of toner to be consumed per sheet of printing paper.
    Type: Grant
    Filed: February 24, 1999
    Date of Patent: February 6, 2001
    Assignee: Daimippon Ink and Chemicals, Inc.
    Inventors: Minoru Nomura, Takashi Ito, Hitoshi Takayanagi, Kazuo Itoya
  • Patent number: 6180308
    Abstract: A liquid developer comprised of a nonpolar liquid, resin, colorant, and a charge acceptance component comprised of an aluminum complex of the formulas, or mixtures thereof wherein R1 is selected from the group consisting of hydrogen and alkyl, and n represents the number of R1 substituents.
    Type: Grant
    Filed: January 27, 2000
    Date of Patent: January 30, 2001
    Assignee: Xerox Corporation
    Inventors: David H. Pan, Weizhong Zhao, John W. Spiewak, Christopher M. Knapp
  • Patent number: 6180305
    Abstract: An organic photoreceptor (“OPR”) including a barrier layer formed from a barrier layer coating composition including a cellulosic resin, methylvinyl ether/maleic anhydride copolymer, a polyamide, a crosslinker, and a combination thereof, provides sufficient protection to the organic photoreceptor from damage due to corona-induced charge injection; is substantially inert with respect to the organic photoconductive layer; exhibits sufficient resiliency to withstand shear, compressional and tensional forces exerted on the belt as it passes through an electrophotographic system when the photoreceptor is used in an endless belt form; and provides sufficient protection to limit or prevent a liquid toner from contacting the organic photoconductor that may result in crazing and/or cracking of the organic photoreceptor during use.
    Type: Grant
    Filed: February 16, 2000
    Date of Patent: January 30, 2001
    Assignee: Imation Corp.
    Inventors: James H. Ackley, James E. Lindquist, Zbigniew Tokarski
  • Patent number: 6180297
    Abstract: Disclosed is a process which comprises (a) providing a migration imaging member comprising (1) a substrate, (2) an infrared or red light radiation sensitive layer comprising a pigment predominantly sensitive to infrared or red light radiation, and (3) a softenable layer comprising a softenable material, a charge transport material, and a photosensitive migration marking material predominantly sensitive to radiation at a wavelength other than that to which the infrared or red light sensitive pigment is predominantly sensitive; (b) uniformly charging the imaging member; (c) subsequent to step (b), uniformly exposing the charged imaging member to a source of activating radiation with a wavelength to which the migration marking material is sensitive, wherein a filter comprising the infrared or red light radiation sensitive pigment is situated between the radiation source and the imaging member; (d) subsequent to step (b), exposing the imaging member to infrared or red light radiation at a wavelength to which the
    Type: Grant
    Filed: May 1, 1995
    Date of Patent: January 30, 2001
    Assignee: Xerox Corporation
    Inventors: Man C. Tam, Edward G. Zwartz
  • Patent number: 6180309
    Abstract: A process for preparing an imaging member includes applying a first organic layer to an imaging member substrate, treating the first organic layer with one of corona discharge or plasma discharge; and applying a second organic layer to the first organic layer.
    Type: Grant
    Filed: November 26, 1999
    Date of Patent: January 30, 2001
    Assignee: Xerox Corporation
    Inventors: David J Maty, Robert L Flanagan
  • Patent number: 6180310
    Abstract: A process for fabricating an electrophotographic imaging member including providing a cylindrical member, depositing on the cylindrical member a coating of a first charge transport layer coating solution by dip coating the cylindrical member in a bath of the first charge transport layer coating solution in a dip coating vessel, the first charge transport layer coating solution including a film forming polymer, a charge transport material, and at least one volatile solvent, the first charge transport layer coating solution having a first predetermined viscosity and the solvent having a viscosity less than the first predetermined viscosity, recirculating undeposited first charge transport layer coating solution from the dip coating vessel to a charge transport layer coating solution vessel and back to the dip coating vessel, repeatedly and sequentially depositing on fresh cylindrical members a coating of the recirculating undeposited first charge transport layer coating solution by dip coating the fresh cylindr
    Type: Grant
    Filed: August 14, 2000
    Date of Patent: January 30, 2001
    Assignee: Xerox Corporation
    Inventor: Jeremy B. Pinsly
  • Patent number: 6180307
    Abstract: A layered particle for use in forming toner may be formed by forming a core region; polymerizing in the presence of the core region at least one monomer feed to form at least one intermediate layer on the core region; and polymerizing in the presence of the core region with at least one intermediate layer thereon a final monomer feed. In the process, each monomer feed is different from the previous monomer feed so as to form different polymer layers.
    Type: Grant
    Filed: March 10, 2000
    Date of Patent: January 30, 2001
    Assignee: Xerox Corporation
    Inventor: Grazyna E. Kmiecik-Lawrynowicz
  • Patent number: 6177222
    Abstract: A process which comprises forming an image on a substrate, and developing the image with toner, and wherein the substrate contains a coating of a polyester and there is enabled images of high uniform gloss.
    Type: Grant
    Filed: March 12, 1998
    Date of Patent: January 23, 2001
    Assignee: Xerox Corporation
    Inventors: T. Brian McAneney, Edward G. Zwartz, Kirit N. Naik, Fernando P. Yulo, Sandra J. Gardner, James H. Sharp, Shadi L. Malhotra
  • Patent number: 6174637
    Abstract: A photo conducting imaging member has a charge generator layer including a binder containing at least a polycarbonate of formula (I):
    Type: Grant
    Filed: January 19, 2000
    Date of Patent: January 16, 2001
    Assignee: Xerox Corporation
    Inventors: Kathleen M. Carmichael, Satish R. Parikh
  • Patent number: 6174641
    Abstract: The present invention relates to a non-magnetic toner for developing electrostatic latent images, having; an average degree of roundness of not less than 0.960, a standard deviation of degree of roundness of not more than 0.040, a value of D/d50 of not less than 0.40, in which D=6/(&rgr;·S) (&rgr; is a true density of toner (g/cm3), and S is a BET specific surface area of toner (m2/g)); d50 is an average weight particle size of toner, and an adhesive stress of 6 g/cm2 or less under a compression of 1 kg/cm2. The non-magnetic toner for developing electrostatic latent images provides high-quality images not only in low-speed areas, but also in high-speed areas, and has a superior transferring properties.
    Type: Grant
    Filed: April 11, 2000
    Date of Patent: January 16, 2001
    Assignee: Minolta Co., Ltd.
    Inventors: Minoru Nakamura, Katsunori Kurose, Masahiro Anno, Chikara Tsutsui, Hiroyuki Fukuda
  • Patent number: 6174639
    Abstract: Disclosed are a positive charging color toner comprising a coloring agent and a positive charging electric charge controlling material in a fixing resin, wherein the fixing rein is an urethane-modified polyester resin having an acid value of not more than 5 KOHmg/g, a hydroxyl value of not more than 9 KOHmg/g, a weight-average molecular weight of 8,000 to 120,000 and a number-average molecular weight of 2,000 to 70,000, and the positive charging electric charge controlling material is (a) a quaternary ammonium salt having a melting point of not less than 200° C., or (b) a styrene-acrylate copolymer having a trisubstituted amminio group and a glass transition temperature Tg of not less than 55° C.
    Type: Grant
    Filed: March 31, 2000
    Date of Patent: January 16, 2001
    Assignee: Mita Industrial Co., Ltd.
    Inventors: Yoshitake Shimizu, Takahiro Ishihara, Hiroshi Shimoyama, Toyotsune Inoue, Takashi Nishino, Kazuya Nagao, Kenshi Matsui, Takayuki Itakura, Norio Horikami
  • Patent number: 6171745
    Abstract: The present invention related to a toner used in a toner-jetting system wherein the toner is jettingly adhered to a recording medium in a direct manner, the toner having a specific angle of repose, a specific mean roundness and/or a specific distribution of a particle size.
    Type: Grant
    Filed: April 18, 2000
    Date of Patent: January 9, 2001
    Assignee: Minolta Co., Ltd.
    Inventors: Yasuhiro Ohno, Ken Tanino, Toshiya Natsuhara, Masahiro Anno
  • Patent number: 6171746
    Abstract: The present invention relates to a toner used in a toner-jetting system wherein the toner is jettingly adhered to a recording medium in a direct manner, said toner satisfying a specific relationship between an average quantity of charge (x)(&mgr;C/g) and a distribution deviation of quantity of charge (y).
    Type: Grant
    Filed: May 10, 2000
    Date of Patent: January 9, 2001
    Assignee: Minolta Co., Ltd.
    Inventors: Toshiya Natsuhara, Ken Tanino, Yasuhiro Ohno