Patents by Inventor Divya Chopra

Divya Chopra 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: 10294343
    Abstract: The present invention is based on a surprising discovery of new packaging materials used to package substances, such as foods, preventing the photo-oxidation of entities found in these substances. Specifically, these new packaging materials include a mixture of polymer resins having novel and specific ratios of filler, preferably calcium carbonate, and titanium dioxide resulting in the material having unexpected properties.
    Type: Grant
    Filed: September 22, 2015
    Date of Patent: May 21, 2019
    Assignee: THE CHEMOURS COMPANY FC, LLC
    Inventors: Philipp Martin Niedenzu, Denise Conner, Divya Chopra
  • Publication number: 20160083554
    Abstract: The present invention is based on a surprising discovery of new packaging materials used to package substances, such as foods, preventing the photo-oxidation of entities found in these substances. Specifically, these new packaging materials include a mixture of polymer resins having novel and specific ratios of filler, preferably calcium carbonate, and titanium dioxide resulting in the material having unexpected properties.
    Type: Application
    Filed: September 22, 2015
    Publication date: March 24, 2016
    Inventors: PHILIPP MARTIN NIEDENZU, DENISE CONNER, DIVYA CHOPRA
  • Patent number: 7413685
    Abstract: A method and composition is disclosed for making conductive flow field separator plates having reduced resistivity, lower weight and lower cost. The plates are made by blending from about 0.5 wt % to about 40 wt %, preferably from about 1 wt % to about 30 wt %, most preferably from about 5 wt % to about 20 wt %, of the liquid crystal polymer; from about 0.5 wt % to about 40 wt %, preferably from about 1 wt % to about 30 wt %, most preferably from about 5 wt % to about 20 wt % of the poly(styrene-co-maleic anhydride); and from about 20 wt % to about 99 wt %, preferably from about 60 wt % to about 98 wt %, most preferably from about 70 wt % to about 90 wt % of the conductive filler. The blend is then moulded to form the conductive flow field separator plates.
    Type: Grant
    Filed: May 29, 2007
    Date of Patent: August 19, 2008
    Assignee: E.I. du Pont Canada Company
    Inventors: Yuqi Cai, Divya Chopra, John Fisher
  • Publication number: 20070228338
    Abstract: A method and composition is disclosed for making conductive flow field separator plates having reduced resistivity, lower weight and lower cost. The plates are made by blending from about 0.5 wt % to about 40 wt %, preferably from about 1 wt % to about 30 wt %, most preferably from about 5 wt % to about 20 wt %, of the liquid crystal polymer; from about 0.5 wt % to about 40 wt %, preferably from about 1 wt % to about 30 wt %, most preferably from about 5 wt % to about 20 wt % of the poly(styrene-co-maleic anhydride); and from about 20 wt % to about 99 wt %, preferably from about 60 wt % to about 98 wt %, most preferably from about 70 wt % to about 90 wt % of the conductive filler. The blend is then moulded to form the conductive flow field separator plates.
    Type: Application
    Filed: May 29, 2007
    Publication date: October 4, 2007
    Inventors: Yuqi Cai, Divya Chopra, John Fisher
  • Patent number: 7153603
    Abstract: The present invention provides a process for decreasing the resistivity of a non-machined conductive flow field plate for use in a fuel cell. The process includes the step of annealing the conductive flow field plate by heating the conductive flow field plate to a temperature between 25° C. (room temperature) and a temperature slightly lower than the material softening temperature of the material composition of the conductive flow field plate; maintaining the conductive flow field plate at that temperature for an effective period of time; and, cooling the conductive flow field plate to room temperature.
    Type: Grant
    Filed: March 17, 2003
    Date of Patent: December 26, 2006
    Assignee: E. I. duPont Canada Company
    Inventors: Yuqi Cai, Divya Chopra, John C. Fisher
  • Publication number: 20060169952
    Abstract: A method and composition is disclosed for making conductive flow field separator plates having reduced resistivity, lower weight and lower cost. The plates are made by blending from about 0.5 wt % to about 40 wt %, preferably from about 1 wt % to about 30 wt %, most preferably from about 5 wt % to about 20 wt %, of the liquid crystal polymer; from about 0.5 10 wt % to about 40 wt %, preferably from about 1 wt % to about 30 wt %, most preferably from about 5 wt % to about 20 wt % of the poly(styrene-co-maleic anhydride); and from about 20 wt % to about 99 wt %, preferably from about 60 wt % to about 98 wt %, most preferably from about 70 wt % to about 90 wt % of the conductive filler. The blend is then moulded to form the conductive flow field separator plates.
    Type: Application
    Filed: September 11, 2003
    Publication date: August 3, 2006
    Inventors: Yuqi Cai, Divya Chopra, John Fisher
  • Publication number: 20050181260
    Abstract: An electrically conductive flow field separator plate is disclosed for use in a proton exchange membrane fuel cell. The plate comprises a frame portion, a central planar portion within the frame and a flow field formed in a surface of the central planar portion. The frame portion is elastomeric so as to form a seal with adjacent fuel cell components thereby eliminating the use of separate sealing elements. The frame and the central planar portion are of unitary construction and comprise from about 10 wt. % to about 50 wt. % of elastomer and from about 50 wt. % to about 90 wt. % of conductive filler.
    Type: Application
    Filed: June 18, 2003
    Publication date: August 18, 2005
    Inventors: Yuqi Cai, Tuyu Xie, Divya Chopra, Michael Waller, Jay Peters
  • Publication number: 20050167882
    Abstract: The present invention provides a process for decreasing the resistivity of a non-machined conductive flow field plate for use in a fuel cell. The process includes the step of annealing the conductive flow field plate by heating the conductive flow field plate to a temperature between 25° C. (room temperature) and a temperature slightly lower than the material softening temperature of the material composition of the conductive flow field plate; maintaining the conductive flow field plate at that temperature for an effective period of time; and, cooling the conductive flow field plate to room temperature.
    Type: Application
    Filed: March 17, 2003
    Publication date: August 4, 2005
    Inventors: Yuqi Cai, Divya Chopra, John Fisher
  • Publication number: 20050074480
    Abstract: The present invention relates to a process for coating a surface of a polymer film with a release coating composition to provide a release film for use in high temperature and/or high humidity conditions, which comprises coating at least one surface of the polymer film with an aqueous of from about 0.2 to about 6.0% by weight of at least one hydroxypropyl methyl cellulose having hydroxypropyl molar substitution of from 0 to about 0.82 and from about 1% to about 35% by weight of alcohol to provide a coating weight of at least about 0.004 lb/ream per side and drying the coated film to set the coating. Also disclosed is a release polymer film coated on at least one surface with a composition comprising from about 0.2 to about 6.0% by weight of at least one hydroxypropyl methylcellulose having hydroxypropyl molar substitution of from 0 to about 0.82 and the coating weight is at least about 0.004 lb/ream.
    Type: Application
    Filed: July 16, 2004
    Publication date: April 7, 2005
    Inventors: Divya Chopra, Benjamin Smillie, Theodore Lang
  • Publication number: 20050042496
    Abstract: An improved process for fabricating an electrically conductive shaped article is disclosed. The process includes one or more process stages selected from the group consisting of: preparing one or more feeds of the plastic and fillers; feeding the plastic and fillers to a melt compounding stage wherein a homogeneous melt of the composition is obtained; transferring the homogeneous melt ; and subjecting the homogeneous melt to a moulding process to produce the conductive shaped article. One or more of the process stages is conducted under low shear strain conditions so that the article has a through-plane resistivity of less than about 600 ?Ohm-m. Also disclosed are the conductive plates having improved performance properties such as flexural strength, conductivity and surface smoothness.
    Type: Application
    Filed: February 13, 2003
    Publication date: February 24, 2005
    Inventors: Mukesh Bisara, Yuqi Cai, Divya Chopra, Alistair Mollison, John Fisher
  • Publication number: 20040191608
    Abstract: Disclosed is a method of making a current collector plate for use in a proton exchange membrane fuel cell. The method includes the steps of: (a) molding the current collector plate by injection, compression or any other molding process from a resin/conductive filler composition; (b) measuring the current collector plate's average thickness; (c) measuring the current collector plate's through-plane resistivity; (d) removing a portion of the current collector plate's surface layer by abrasion; and (e) repeating steps (a) to (d) until a desired plate thickness is removed. The desired plate thickness removed is no more than about 10 micrometers, and preferably about 5 micrometers.
    Type: Application
    Filed: June 23, 2003
    Publication date: September 30, 2004
    Inventors: Divya Chopra, James Guolla, Yuqi Cai, Larin Godfroy, Peter Andrin, John Charles Fisher, Andrew Chi Yan Li
  • Patent number: 6776831
    Abstract: The present invention relates to a release coating composition that may be applied to a film that may then be used as a substrate useful for applications requiring release for a broad range of temperatures and high humidity conditions, which temperatures may range from about 20° C. to about 210° C. These applications include release substrate used in the manufacture of calendared cured sheet rubber and molding paste composites, such as sheet molding compound (SMC), thick molding compound (TMC), bulk molding compound (BMC) and fiberglass composites. The release coating composition comprises a solution of a hydroxypropyl methylcellulose having hydroxypropyl molar substitution of from 0 to about 0.82. In a preferred form, particulate solids are present in the composition.
    Type: Grant
    Filed: July 20, 2001
    Date of Patent: August 17, 2004
    Assignee: DuPont Canada Inc.
    Inventors: Divya Chopra, Benjamin Andrew Smillie, Theodore John Lang
  • Publication number: 20040058249
    Abstract: Separator plates for use in a fuel cell comprising a conductive polymeric composite that is reinforced with an electrically conductive mesh or screen, and a method for making the reinforced separator plates.
    Type: Application
    Filed: December 13, 2002
    Publication date: March 25, 2004
    Inventors: Yuqi Cai, Divya Chopra, Larin Godfroy, John C. Fisher
  • Publication number: 20040046282
    Abstract: The present invention provides a process for decreasing the resistivity of a non-machined conductive flow field plate for use in a fuel cell. The process includes the step of annealing the conductive flow field plate by heating the conductive flow field plate to a temperature between 25° C. (room temperature) and a temperature slightly lower than the material softening temperature of the material composition of the conductive flow field plate; maintaining the conductive flow field plate at that temperature for an effective period of time; and, cooling the conductive flow field plate to room temperature.
    Type: Application
    Filed: March 17, 2003
    Publication date: March 11, 2004
    Inventors: Yuqi Cai, Divya Chopra, John C. Fisher
  • Publication number: 20020136843
    Abstract: The present invention relates to a release coating composition that may be applied to a film that may then be used as a substrate useful for applications requiring release for a broad range of temperatures and high humidity conditions, which temperatures may range from about 20° C. to about 210° C. These applications include release substrate used in the manufacture of calendared cured sheet rubber and molding paste composites, such as sheet molding compound (SMC), thick molding compound (TMC), bulk molding compound (BMC) and fiberglass composites. The release coating composition comprises a solution of a hydroxypropyl methylcellulose having hydroxypropyl molar substitution of from 0 to about 0.82. In a preferred form, particulate solids are present in the composition.
    Type: Application
    Filed: July 20, 2001
    Publication date: September 26, 2002
    Inventors: Divya Chopra, Benjamin Andrew Smillie, Theodore John Lang