Patents by Inventor Raj D. Patel

Raj D. Patel 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).

  • Toner processes
    Publication number: 20040265729
    Abstract: A toner process comprised of heating a mixture of an acicular magnetite dispersion, a colorant dispersion, a wax dispersion, a first latex containing a crosslinked resin, a second latex containing a resin substantially free of crosslinking, a coagulant and a silica, and wherein the toner resulting possesses a shape factor of from about 120 to about 150.
    Type: Application
    Filed: June 25, 2003
    Publication date: December 30, 2004
    Applicant: Xerox Corporation
    Inventor: Raj D. Patel
  • Toner processes
    Publication number: 20040265728
    Abstract: A toner process involving the heating a mixture of an acicular magnetite dispersion, a colorant dispersion, a wax dispersion, a first latex containing a crosslinked resin, and a second latex containing a resin free of crosslinking in the presence of a coagulant to provide aggregates, stabilizing the aggregates with a silicate salt dissolved in a base, and further heating the aggregates to provide coalesced toner particles.
    Type: Application
    Filed: June 25, 2003
    Publication date: December 30, 2004
    Applicant: Xerox Corporation
    Inventors: Raj D. Patel, Michael A. Hopper, Edward G. Zwartz, Cuong Vong, Allan K. Chen
  • Emulsion aggregation toner containing a mixture of waxes incorporating an improved process to prevent wax protrusions and coarse particles
    Patent number: 6808851
    Abstract: A process for the preparation of emulsion aggregation toner particles with high pigment loading having a reduced number of wax protrusions on the surface of the toner particles and fewer coarse toner particles. The process includes the introduction of a wax having a molecular weight between about 500 and 2,500, or a blend of waxes having different a molecular weight between 500 and 2,500.
    Type: Grant
    Filed: January 15, 2003
    Date of Patent: October 26, 2004
    Assignee: Xerox Corporation
    Inventors: Joseph A. Bartel, Patricia A. Burns, Raj D. Patel, Enno E. Agur, Danielle C. Boils, Edward G. Zwartz, Paul J. Gerroir, Maria N. V. McDougall
  • Toner processes
    Patent number: 6780559
    Abstract: A toner process involving mixing a colorant dispersion and a metal oxide with a latex emulsion comprised of polymer, water, and an anionic surfactant, adding a cationic coagulant followed by heating the mixture to a temperature below about the glass transition temperature (Tg) of the latex polymer particles to provide toner size aggregates comprised of polymer pigment and dye, heating above about the Tg of the polymer and isolating the resulting product.
    Type: Grant
    Filed: August 7, 2002
    Date of Patent: August 24, 2004
    Assignee: Xerox Corporation
    Inventors: Richard P. N. Veregin, Raj D. Patel, Maria N. V. McDougall
  • TONER PROCESSES
    Publication number: 20040146797
    Abstract: A toner process involving mixing a colorant dispersion comprising an acicular magnetite dispersion and a colorant dispersion with a latex, a wax dispersion, a crosslinked resin, and a coagulant.
    Type: Application
    Filed: January 29, 2003
    Publication date: July 29, 2004
    Applicant: Xerox Corporation
    Inventors: Raj D. Patel, Michael A. Hopper, Edward G. Zwartz, Allan K. Chen
  • Toner processes
    Patent number: 6767684
    Abstract: A toner process involving mixing a colorant dispersion comprising an acicular magnetite dispersion and a colorant dispersion with a latex, a wax dispersion, a crosslinked resin, and a coagulant.
    Type: Grant
    Filed: January 29, 2003
    Date of Patent: July 27, 2004
    Assignee: Xerox Corporation
    Inventors: Raj D. Patel, Michael A. Hopper, Edward G. Zwartz, Allan K. Chen
  • EMULSION AGGREGATION TONER CONTAINING A MIXTURE OF WAXES INCORPORATING AN IMPROVED PROCESS TO PREVENT WAX PROTRUSIONS AND COARSE PARTICLES
    Publication number: 20040137357
    Abstract: A process for the preparation of emulsion aggregation toner particles with high pigment loading having a reduced number of wax protrusions on the surface of the toner particles and fewer coarse toner particles. The process includes the introduction of a wax having a molecular weight between about 500 and 2,500, or a blend of waxes having different a molecular weight between 500 and 2,500.
    Type: Application
    Filed: January 15, 2003
    Publication date: July 15, 2004
    Inventors: Joseph A. BARTEL, Patricia A. BURNS, Raj D. PATEL, Enno E. AGUR, Danielle C. BOILS, Edward G. ZWARTZ, Paul J. GERROIR, Maria N.V. MCDOUGALL
  • Toner processes
    Publication number: 20040058268
    Abstract: A toner process involving mixing a colorant dispersion and a metal oxide with a latex emulsion comprised of polymer, water, and an anionic surfactant, adding a cationic coagulant followed by heating the mixture to a temperature below about the glass transition temperature (Tg) of the latex polymer particles to provide toner size aggregates comprised of polymer pigment and dye, heating above about the Tg of the polymer and isolating the resulting product.
    Type: Application
    Filed: August 7, 2002
    Publication date: March 25, 2004
    Applicant: Xerox Corporation
    Inventors: Richard P. N. Veregin, Raj D. Patel, Maria N.V. McDougall
  • Document security processes
    Publication number: 20040037947
    Abstract: A process for generating on a substrate, such as a document, a security mark comprised of a glossy ink containing a colorant.
    Type: Application
    Filed: August 20, 2002
    Publication date: February 26, 2004
    Applicant: Xerox Corporation
    Inventors: Raj D. Patel, Michael A. Hopper, H. Bruce Goodbrand
  • Toner coagulant processes
    Patent number: 6673505
    Abstract: A process for the preparation of a toner by mixing a colorant, a latex, optionally a wax and a polyamine salt coagulant to form toner size aggregates, wherein the polyamine salt is then neutralized or converted to an amide or hydrolyzed to an acid by the introduction of a base followed by a pH reduction with an acid to enable rapid coalescence or fusion of the aggregates.
    Type: Grant
    Filed: March 25, 2002
    Date of Patent: January 6, 2004
    Assignee: Xerox Corporation
    Inventors: Lu Jiang, Armin R. Volkel, Chieh-Min Cheng, Michael A. Hopper, Walter Mychajlowskij, Raj D. Patel
  • Document security processes
    Patent number: 6673500
    Abstract: A process comprising applying a toner security mark on a document generated by xerographic means, and which mark possesses white glossy characteristics, and wherein said toner is comprised of a waterborne polymer resin and a colorant, and optionally a second security mark generated by a toner comprised of a waterborne polymer resin and a UV fluorescent component.
    Type: Grant
    Filed: August 20, 2002
    Date of Patent: January 6, 2004
    Assignee: Xerox Corporation
    Inventors: Raj D. Patel, Fatima M. Mayer, Michael A. Hopper, Kurt I. Halfyard
  • Document security processes
    Patent number: 6664017
    Abstract: A process comprising applying a toner security mark on a document generated by xerographic means and which mark possesses white glossy characteristics, and wherein said toner is comprised of a polymer and a colorant.
    Type: Grant
    Filed: August 20, 2002
    Date of Patent: December 16, 2003
    Assignee: Xerox Corporation
    Inventors: Raj D. Patel, Michael A. Hopper, H. Bruce Goodbrand, Kurt I. Halfyard, Nan-Xing Hu
  • Magnetite toner processes
    Patent number: 6656658
    Abstract: A toner process comprising heating an acidified dispersion of an acicular magnetite, a carbon black colorant dispersion, an optional wax dispersion, and an acicular latex.
    Type: Grant
    Filed: March 25, 2002
    Date of Patent: December 2, 2003
    Assignee: Xerox Corporation
    Inventors: Raj D. Patel, Michael A. Hopper, Joseph Bartel, Edward G. Zwartz
  • Toner processes
    Patent number: 6656657
    Abstract: A toner process comprising mixing an acidified dispersion of an acicular magnetite with an anionic latex, an anionic carbon black dispersion, and an anionic wax dispersion.
    Type: Grant
    Filed: March 25, 2002
    Date of Patent: December 2, 2003
    Assignee: Xerox Corporation
    Inventors: Raj D. Patel, Michael A. Hopper, Joseph Bartel, Edward G. Zwartz
  • Marking particles
    Patent number: 6652959
    Abstract: Disclosed are marking particles comprising a resin, a chelating agent, and a spiropyran material which is of the formula The marking particles are prepared by an emulsion aggregation process.
    Type: Grant
    Filed: January 11, 2002
    Date of Patent: November 25, 2003
    Assignee: Xerox Corporation
    Inventors: Daniel A. Foucher, Raj D. Patel, Naveen Chopra, Peter M. Kazmaier
  • Emulsion/aggregation polymeric microspheres for biomedical applications and methods of making same
    Publication number: 20030211035
    Abstract: A method of forming polymeric microspheres for biomedical applications includes forming polymeric microspheres by an emulsion/aggregation process from a precursor monomer species, and treating the polymeric microspheres to attach a biomedical functional material to the polymeric microspheres, where the polymeric microspheres have an average particle diameter of from about 1 to about 15 microns with a narrow particle geometric size distribution. The biomedical functional material may be, for example, a radioactive material, a radioactive precursor material, a bioactive agent, or a ligand.
    Type: Application
    Filed: May 7, 2002
    Publication date: November 13, 2003
    Inventors: Patricia Ann Burns, Raj D. Patel, Hadi Khan Mahabadi, Ronald F. Ziolo
  • Toner processes
    Patent number: 6638677
    Abstract: A process comprising heating a latex, a colorant dispersion, a polytetrafluoroethylene dispersion, and an organo metallic complexing component.
    Type: Grant
    Filed: March 1, 2002
    Date of Patent: October 28, 2003
    Assignee: Xerox Corporation
    Inventors: Raj D. Patel, Valerie M. Farrugia, Daryl Vanbesien, Edward G. Zwartz
  • Toner processes
    Patent number: 6627373
    Abstract: An emulsion aggregation process for the preparation of a magnetite toner, and where the magnetite can function as a negatively charged coagulant to facilitate aggregation of a basic cationic latex, a cationic carbon black dispersion and a cationic wax dispersion.
    Type: Grant
    Filed: March 25, 2002
    Date of Patent: September 30, 2003
    Assignee: Xerox Corporation
    Inventors: Raj D. Patel, Michael A. Hopper
  • TONER PROCESSES
    Publication number: 20030180651
    Abstract: An emulsion aggregation process for the preparation of a magnetite toner, and where the magnetite can function as a coagulant.
    Type: Application
    Filed: March 25, 2002
    Publication date: September 25, 2003
    Applicant: Xerox Corporation
    Inventors: Raj D. Patel, Michael A. Hopper
  • Toner processes
    Publication number: 20030180648
    Abstract: A process which involves the heating of a magnetite dispersion, a colorant dispersion, a latex emulsion, and a coagulant, wherein the coagulant can be a polymetal halide, and the mixture is aggregated by heating below the latex resin glass transition temperature, and thereafter heating above the latex resin glass transition temperature, followed by cooling and isolating the product, which product can be a toner.
    Type: Application
    Filed: March 25, 2002
    Publication date: September 25, 2003
    Applicant: Xerox Corporation
    Inventors: Raj D. Patel, Michael A. Hopper, Vladislav Skorokhod, Richard P. N. Veregin, Michael S. Hawkins, Paul j. Gerroir