Patents by Inventor Shivanthi Easwari Sriskandha

Shivanthi Easwari Sriskandha 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).

  • Patent number: 11048184
    Abstract: A toner process including a) mixing reagents comprising at least one amorphous resin, an optional crystalline resin, an optional styrene, acrylate or styrene/acrylate, an optional wax, and an optional colorant to form an emulsion comprising a resin particle; b) adding at least one aggregating agent and aggregating said resin particle to form a nascent toner particle; c) optionally, adding one or more resins to form a shell on said nascent toner particle to yield a core-shell particle; d) adding a first chelating agent and a second chelating agent; wherein said first chelating agent and said second chelating agent are different; e) freezing particle growth to form an aggregated toner particle; f) coalescing said aggregated toner particle to form a toner particle; and g) optionally, collecting said toner particle.
    Type: Grant
    Filed: January 14, 2019
    Date of Patent: June 29, 2021
    Assignee: Xerox Corporation
    Inventors: Shivanthi Easwari Sriskandha, Richard P. N. Veregin, Guerino G. Sacripante, Edward G. Zwartz, Michael Steven Hawkins
  • Publication number: 20210070988
    Abstract: Melt emulsification may be employed to form elastomeric particulates in a narrow size range when nanoparticles and a sulfonate surfactant are included as emulsion stabilizers. Such processes may comprise combining a polyurethane polymer, a sulfonate surfactant, and nanoparticles with a carrier fluid at a heating temperature at or above a melting point or softening temperature of the polyurethane polymer, applying sufficient shear to disperse the polyurethane polymer as liquefied droplets in the presence of the nanoparticles in the carrier fluid at the heating temperature, cooling the carrier fluid at least until elastomeric particulates in a solidified state form, and separating the elastomeric particulates from the carrier fluid. The polyurethane polymer defines a core and an outer surface of the elastomeric particulates, and the nanoparticles are associated with the outer surface. The elastomeric particulates may have a span of about 0.9 or less.
    Type: Application
    Filed: June 30, 2020
    Publication date: March 11, 2021
    Applicant: Xerox Corporation
    Inventors: Robert Claridge, Cristina Resetco, Shivanthi Easwari Sriskandha, Valerie M. Farrugia, Edward G. Zwartz
  • Publication number: 20210070953
    Abstract: Melt emulsification may be employed to form elastomeric particulates in a narrow size range when nanoparticles are included as an emulsion stabilizer. Such processes may comprise combining a polyurethane polymer and nanoparticles with a carrier fluid at a heating temperature at or above a melting point or a softening temperature of the polyurethane polymer, applying sufficient shear to disperse the polyurethane polymer as liquefied droplets in the presence of the nanoparticles in the carrier fluid at the heating temperature, cooling the carrier fluid at least until elastomeric particulates in a solidified state form, and separating the elastomeric particulates from the carrier fluid. In the elastomeric particulates, the polyurethane polymer defines a core and an outer surface of the elastomeric particulates and the nanoparticles are associated with the outer surface. The elastomeric particulates may have a D50 of about 1 ?m to about 1,000 ?m.
    Type: Application
    Filed: June 30, 2020
    Publication date: March 11, 2021
    Applicant: Xerox Corporation
    Inventors: Cristina Resetco, Shivanthi Easwari Sriskandha, Edward G. Zwartz, Michael S. Hawkins, Valerie M. Farrugia
  • Publication number: 20210070993
    Abstract: Thermoplastic polymer particles can be produced that comprise a thermoplastic polymer and an emulsion stabilizer (e.g., nanoparticles and/or surfactant) associated with an outer surface of the particles. The nanoparticles may be embedded in the outer surface of the particles. Melt emulsification can be used to produce said particles. For example, a method may include: mixing a mixture comprising a thermoplastic polymer, an carrier fluid that is immiscible with the thermoplastic polymer, and the emulsion stabilizer at a temperature greater than a melting point or softening temperature of the thermoplastic polymer and at a shear rate sufficiently high to disperse the thermoplastic polymer in the carrier fluid; cooling the mixture to below the melting point or softening temperature of the thermoplastic polymer to form the thermoplastic polymer particles; and separating the thermoplastic polymer particles from the carrier fluid.
    Type: Application
    Filed: June 30, 2020
    Publication date: March 11, 2021
    Applicant: Xerox Corporation
    Inventors: Valerie M. Farrugia, Cristina Resetco, Michael S. Hawkins, Shivanthi Easwari Sriskandha, Robert Claridge, Carolyn Patricia Moorlag
  • Patent number: 10907016
    Abstract: An organic solvent-free phase-inversion emulsification process for a low molecular weight amorphous polyester resin includes forming a mixture by adding to the amorphous polyester resin: i. a surfactant; ii. an aqueous solution of a neutralizing agent; and iii. a portion of water that is about 40% or less of a total amount of water used to form a phase-inversion emulsion, heating the mixture to dissolve the amorphous polyester resin to provide a dissolved amorphous polyester and adding water up to the total amount of water to the dissolved amorphous polyester to form a latex of the amorphous polyester resin. The resultant latex is used in processes of making a toner composition. A latex of an amorphous polyester resins is made by such processes have latex particles that are unimodal.
    Type: Grant
    Filed: October 26, 2018
    Date of Patent: February 2, 2021
    Assignee: XEROX CORPORATION
    Inventors: Hajir Mokhtari, Shivanthi Easwari Sriskandha, Guerino G. Sacripante
  • Publication number: 20200310274
    Abstract: A polymeric composition including a copolymer comprising a first monomer having a high carbon to oxygen ratio of from about 3 to about 8; a second monomer comprising two or more vinyl groups, wherein the second monomer is present in the copolymer in an amount of from greater than about 8 percent by weight to about 40 percent by weight, based on the weight of the copolymer; and optionally, a third monomer comprising an amine, wherein the third monomer is present in an amount of from about 0.1 percent by weight to about 1.5 percent by weight, based on the weight of the copolymer; and a surfactant, wherein the surfactant has a minimum surface tension at critical micelle concentration of less than about 30 mN/m. A toner including the copolymer as a toner surface additive. An emulsion aggregation toner process including the copolymer as a toner surface additive.
    Type: Application
    Filed: June 4, 2020
    Publication date: October 1, 2020
    Inventors: Richard P. N. Veregin, Shivanthi Easwari Sriskandha, David R. Kurceba, Scott Edward Silver, Melanie Lynn Davis, Cuong Vong
  • Publication number: 20200310268
    Abstract: A toner including toner particles comprising at least one resin, in combination with an optional colorant, and an optional wax; and a copolymer toner additive on at least a portion of an external surface of the toner particles, the copolymer toner additive comprising a first monomer having a high carbon to oxygen ratio of from about 3 to about 8; and a second monomer comprising two or more vinyl groups, wherein the second monomer is present in the copolymer in an amount of from greater than about 8 percent by weight to about 60 percent by weight, based on the weight of the copolymer; wherein the copolymer toner additive has a volume average particle diameter of from about 20 nanometers to less than about 70 nanometers. An emulsion aggregation toner process including the copolymer as a toner surface additive.
    Type: Application
    Filed: March 29, 2019
    Publication date: October 1, 2020
    Inventors: Richard P. N. Veregin, Shivanthi Easwari Sriskandha, David R. Kurceba, Melanie Lynn Davis, Cuong Vong
  • Publication number: 20200307027
    Abstract: A process including providing a three-dimensional printing powder dispersion comprising a three-dimensional printing powder, an optional dispersing agent, and water; providing an emulsion of an organic polymeric additive; combining the three-dimensional printing powder dispersion and the emulsion of organic polymeric additive to form a mixture comprising the three-dimensional printing powder dispersion and the emulsion of organic polymeric additive; and drying the mixture of the three-dimensional printing powder dispersion and the emulsion of organic polymeric additive.
    Type: Application
    Filed: March 29, 2019
    Publication date: October 1, 2020
    Inventors: Richard P. N. Veregin, Karen A. Moffat, Michael Steven Hawkins, Shivanthi Easwari Sriskandha
  • Publication number: 20200301296
    Abstract: Described herein is a method for manufacturing a low gloss toner. The method includes mixing a resin, a colorant and an optional wax in water to form an emulsion. The emulsion is heated in the presence of a polyion coagulant to form a plurality of aggregated particles, wherein the heating is to a temperature of below the glass transition temperature of the resin. Trisodium citrate dihydrate is added to the heated emulsion in amount of from 0.4 weight percent to about 1.0 percent by weight based on of a total weight of reagents while stirring, wherein the trisodium citrate dihydrate. The aggregated particles are heated to a temperature above the glass transition temperature of the resin to form toner particles have a volume average particle diameter of from 4.3 microns to 4.9 microns.
    Type: Application
    Filed: March 18, 2019
    Publication date: September 24, 2020
    Inventors: Shivanthi Easwari Sriskandha, Richard P N Veregin, Edward G. Zwartz, Michael S. Hawkins
  • Patent number: 10725394
    Abstract: A polymeric composition including a copolymer comprising a first monomer having a high carbon to oxygen ratio of from about 3 to about 8; a second monomer comprising two or more vinyl groups, wherein the second monomer is present in the copolymer in an amount of from greater than about 8 percent by weight to about 40 percent by weight, based on the weight of the copolymer; and optionally, a third monomer comprising an amine, wherein the third monomer is present in an amount of from about 0.1 percent by weight to about 1.5 percent by weight, based on the weight of the copolymer; and a surfactant, wherein the surfactant has a minimum surface tension at critical micelle concentration of less than about 30 mN/m. A toner including the copolymer as a toner surface additive. An emulsion aggregation toner process including the copolymer as a toner surface additive.
    Type: Grant
    Filed: March 29, 2019
    Date of Patent: July 28, 2020
    Assignee: Xerox Corporation
    Inventors: Richard P. N. Veregin, Shivanthi Easwari Sriskandha, David R. Kurceba, Scott Edward Silver, Melanie Lynn Davis, Cuong Vong
  • Publication number: 20200225598
    Abstract: A toner process including a) mixing reagents comprising at least one amorphous resin, an optional crystalline resin, an optional styrene, acrylate or styrene/acrylate, an optional wax, and an optional colorant to form an emulsion comprising a resin particle; b) adding at least one aggregating agent and aggregating said resin particle to form a nascent toner particle; c) optionally, adding one or more resins to form a shell on said nascent toner particle to yield a core-shell particle; d) adding a first chelating agent and a second chelating agent; wherein said first chelating agent and said second chelating agent are different; e) freezing particle growth to form an aggregated toner particle; f) coalescing said aggregated toner particle to form a toner particle; and g) optionally, collecting said toner particle.
    Type: Application
    Filed: January 14, 2019
    Publication date: July 16, 2020
    Inventors: Shivanthi Easwari Sriskandha, Richard P. N. Veregin, Guerino G. Sacripante, Edward G. Zwartz, Michael Steven Hawkins
  • Publication number: 20200131317
    Abstract: An organic solvent-free phase-inversion emulsification process for a low molecular weight amorphous polyester resin includes forming a mixture by adding to the amorphous polyester resin: i. a surfactant; ii. an aqueous solution of a neutralizing agent; and iii. a portion of water that is about 40% or less of a total amount of water used to form a phase-inversion emulsion, heating the mixture to dissolve the amorphous polyester resin to provide a dissolved amorphous polyester and adding water up to the total amount of water to the dissolved amorphous polyester to form a latex of the amorphous polyester resin. The resultant latex is used in processes of making a toner composition. A latex of an amorphous polyester resins is made by such processes have latex particles that are unimodal.
    Type: Application
    Filed: October 26, 2018
    Publication date: April 30, 2020
    Inventors: Hajir Mokhtari, Shivanthi Easwari Sriskandha, Guerino G. Sacripante