Patents by Inventor Ratna SINGH

Ratna SINGH 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: 6545063
    Abstract: The invention relates to the addition of &agr;-methyl styrene, isobutanol and/or isopropanol to reduce vapor pressure, improve k-factor, enhance the solubility of the blowing agent in the premix and/or improve the processing characteristics of polyurethane and polyisocyanurate closed-cell foams prepared with a blowing agent comprising a hydrofluorocarbon selected from the group consisting of 1,1,1,3,3-pentafluoropropane, 1,1,1,2-tetrafluoroethane, 1,1,2,2-tetrafluoroethane, and mixtures thereof.
    Type: Grant
    Filed: September 10, 1999
    Date of Patent: April 8, 2003
    Assignee: AlliedSignal Inc.
    Inventors: Mary Charlotte Bogdan, Leslie Bruce Bement, Barbara Ruth Decaire, Dennis Paul Konopa, Harold John Kieta, Rajiv Ratna Singh
  • Patent number: 6534467
    Abstract: The invention relates to azeotropic and azeotrope-like mixtures of 1,2,2-trichloro-1,3,3,3-tetrafluoropropane (commonly known as HCFC-224aa, and with the IUPAC name of 2,2,3-trichloro-1,1,1,3-tetrafluoropropane;registry number 139754-75-9) and hydrogen fluoride (hydrofluoric acid), which are useful as intermediates in the production of 1,1,3,3,3-pentafluoropropane (HFC-245-fa) and 1,1,1,2,2,3,3-heptafluoropropane (HFC-227ca).
    Type: Grant
    Filed: January 24, 2001
    Date of Patent: March 18, 2003
    Assignee: Honeywell International Inc.
    Inventors: Hang Thanh Pham, Rajiv Ratna Singh, Hsueh Sung Tung
  • Patent number: 6526764
    Abstract: Hydrofluorocarbon refrigerants are not soluble in hydrocarbon oil. Retrofitting refrigeration equipment with hydrofluorocarbons generally entails the use of expensive polyol ester (POE) lubricants. The invention provides hydrofluorocarbon refrigerant compositions that are soluble in hydrocarbon oil thus allowing for a simpler and less expensive retrofit option to the refrigerant user.
    Type: Grant
    Filed: September 27, 2000
    Date of Patent: March 4, 2003
    Assignee: Honeywell International Inc.
    Inventors: Rajiv Ratna Singh, David Paul Wilson, Raymond Hilton Percival Thomas, Robert Gerard Richard
  • Patent number: 6524496
    Abstract: Provided are azeotropic and azeotrope-like mixtures of 1,1,1,3,3-pentafluoropropane (HFC-245fa) and 1-chloro-1,1,3,3,3-pentafluoropropane (HCFC-235fa) that are useful as intermediates in the production of HFC-245fa. A process for separating HFC-245fa and HCFC-235fa is also provided. HFC-245fa is useful as a nontoxic, zero ozone depleting fluorocarbon useful as solvents, blowing agents, refrigerants, cleaning agents, aerosol propellants, heat transfer media, gaseous dielectrics, fire extinguishing compositions and power cycle working fluids.
    Type: Grant
    Filed: March 21, 2001
    Date of Patent: February 25, 2003
    Assignee: Honeywell International Inc.
    Inventors: Kane David Cook, Rajiv Ratna Singh, Hsueh Sung Tung
  • Patent number: 6516837
    Abstract: Provided are methods of introducing environmentally desirable refrigerants into refrigeration systems. The present methods involve recharging a refrigerant system that contains a chlorine-containing refrigerant and a lubricant comprising the steps of (a) removing the chlorine-containing refrigerant from the refrigeration system while retaining a substantial portion of the lubricant in said system; and (b) introducing to said system a composition comprising: (i) a refrigerant; (ii) a surfactant; and (iii) a solubilizing agent.
    Type: Grant
    Filed: August 30, 2001
    Date of Patent: February 11, 2003
    Assignee: Honeywell International Inc.
    Inventors: Raymond Hilton Percival Thomas, Roy Phillip Robinson, Rajiv Ratna Singh, David Paul Wilson
  • Patent number: 6514928
    Abstract: This invention provides azeotrope-like compositions of 1,1,1,3,3-pentafluoropropane and water that are environmentally desirable for use as refrigerants, aerosol propellants, metered dose inhalers, blowing agents for polymer foam, heat transfer media, and gaseous dielectrics.
    Type: Grant
    Filed: March 15, 1999
    Date of Patent: February 4, 2003
    Assignee: AlliedSignal Inc.
    Inventors: Leslie Bruce Bement, Mary Charlotte Bogdan, Clayton Herbert Carson, Peter Brian Logsdon, Hang Thanh Pham, Rajiv Ratna Singh, Hsueh Sung Tung, Ronald Riegal, David John Williams, Kevin Donald Uhrich
  • Patent number: 6500358
    Abstract: The present invention provides refrigerant blends which are replacements for chlorodifluoromethane(HCFC-22). The present blends have refrigeration characteristics which are similar to HCFC-22. The blends comprise from about 10 to about 90 weight percent of a first component selected from the group consisting of 1,1,1-trifluoroethane, difluoromethane, propane, and mixtures thereof; from about 1 to about 50 weight percent of a second component selected from the group consisting of hydrofluorocarbon having 1 to 3 carbon atoms, fluorocarbon having 1 to 3 carbon atoms, inorganic compound, and mixtures thereof having a boiling point at atmospheric pressure in the range from about −90 degrees C to less than −50 degrees C; and from about 1 to about 50 weight percent of a third component which is hydrofluorocarbon having 1 to 3 carbon atoms, other than 1,1,1-trifluoroethane, having a boiling point at atmospheric pressure in the range from about −50 degrees C to about 31 10 degrees C.
    Type: Grant
    Filed: November 6, 2001
    Date of Patent: December 31, 2002
    Assignee: Honeywell International Inc.
    Inventors: Rajiv Ratna Singh, David Paul Wilson
  • Patent number: 6500795
    Abstract: The invention relates to azeotropic and azeotrope-like mixtures of 1-chloro-1,3,3,3-tetrafluoropropane (HCFC-244fa) and hydrogen fluoride, which are useful as intermediates in the production of HCFC-244fa.
    Type: Grant
    Filed: January 24, 2001
    Date of Patent: December 31, 2002
    Assignee: Honeywell International Inc.
    Inventors: Hang Thanh Pham, Rajiv Ratna Singh, Hsueh Sung Tung, Milton Cook
  • Patent number: 6488817
    Abstract: A process for the purification of difluoromethane comprising: (a) subjecting a mixture comprising at least difluoromethane (HFC-32) and dichlorodifluoromethane (CFC-12) to a first distillation step in which a majority of either CFC-12 or HFC-32 is concentrated in a first distillate and a majority of the other component is concentrated in a first bottoms; and (b) subjecting the first distillate in step (a) to at least one additional second distillation step conducted at a different pressure in which a majority of the component concentrated in said first distillate is concentrated in a second bottoms and in which the other component is concentrated in a second distillate; and (c) recovering purified HFC-32 from one of said first or second bottoms.
    Type: Grant
    Filed: March 31, 1998
    Date of Patent: December 3, 2002
    Assignee: AlliedSignal Inc.
    Inventors: Charles Francis Swain, Rajiv Ratna Singh, Hang Thanh Pham
  • Publication number: 20020177537
    Abstract: Provided are azeotropic and azeotrope-like mixtures of 1,1,1,3,3-pentafluoropropane (HFC-245fa) and 1-chloro-1,1,3,3,3-pentafluoropropane (HCFC-235fa) that are useful as intermediates in the production of HFC-245fa. A process for separating HFC-245fa and HCFC-235fa is also provided. HFC-245fa is useful as a nontoxic, zero ozone depleting fluorocarbon useful as solvents, blowing agents, refrigerants, cleaning agents, aerosol propellants, heat transfer media, gaseous dielectrics, fire extinguishing compositions and power cycle working fluids.
    Type: Application
    Filed: March 21, 2001
    Publication date: November 28, 2002
    Inventors: Kane David Cook, Rajiv Ratna Singh, Hsueh Sung Tung
  • Patent number: 6475971
    Abstract: The invention relates to azeotropic and azeotrope-like mixtures of 1,2-dichloro-3,3,3-trifluoropropene (HCFC-1223xd) and hydrogen fluoride, which are useful as intermediates in the production of HCFC-1223xd.
    Type: Grant
    Filed: January 24, 2001
    Date of Patent: November 5, 2002
    Assignee: Honeywell International Inc.
    Inventors: Hang Thanh Pham, Rajiv Ratna Singh, Hsueh Sung Tung
  • Publication number: 20020142927
    Abstract: The invention relates to azeotropic and azeotrope-like mixtures of 1-chloro-1,3,3,3-tetrafluoropropane (HCFC-244fa) and hydrogen fluoride, which are useful as intermediates in the production of HCFC-244fa.
    Type: Application
    Filed: January 24, 2001
    Publication date: October 3, 2002
    Inventors: Hang Thanh Pham, Rajiv Ratna Singh, Hsueh Sung Tung, Milton Cook
  • Publication number: 20020137645
    Abstract: The invention relates to azeotropic and azeotrope-like mixtures of 1,2-dichloro-3,3,3-trifluoropropene (HCFC-1223xd) and hydrogen fluoride, which are useful as intermediates in the production of HCFC-1223xd.
    Type: Application
    Filed: January 24, 2001
    Publication date: September 26, 2002
    Inventors: Hang Thanh Pham, Rajiv Ratna Singh, Hsueh Sung Tung
  • Publication number: 20020137646
    Abstract: The invention relates to azeotropic and azeotrope-like mixtures of 1,2,2-trichloro-1,3,3,3-tetrafluoropropane (HCFC-224aa) and hydrogen fluoride, which are useful as intermediates in the production of HCFC-224aa.
    Type: Application
    Filed: January 24, 2001
    Publication date: September 26, 2002
    Inventors: Hang Thanh Pham, Rajiv Ratna Singh, Hsueh Sung Tung
  • Publication number: 20020121623
    Abstract: The present invention provides refrigerant blends which are replacements for chlorodifluoromethane(HCFC-22). The present blends have refrigeration characteristics which are similar to HCFC-22. The blends comprise from about 10 to about 90 weight percent of a first component selected from the group consisting of 1,1,1-trifluoroethane, difluoromethane, propane, and mixtures thereof; from about 1 to about 50 weight percent of a second component selected from the group consisting of hydrofluorocarbon having 1 to 3 carbon atoms, fluorocarbon having 1 to 3 carbon atoms, inorganic compound, and mixtures thereof having a boiling point at atmospheric pressure in the range from about −90 degrees C. to less than −50 degrees C.; and from about 1 to about 50 weight percent of a third component which is hydrofluorocarbon having 1 to 3 carbon atoms, other than 1,1,1-trifluoroethane, having a boiling point at atmospheric pressure in the range from about −50 degrees C. to about −10 degrees C.
    Type: Application
    Filed: November 6, 2001
    Publication date: September 5, 2002
    Inventors: Rajiv Ratna Singh, David Paul Wilson
  • Publication number: 20020046568
    Abstract: Provided are methods of introducing environmentally desirable refrigerants into refrigeration systems. The present methods involve recharging a refrigerant system that contains a chlorine-containing refrigerant and a lubricant comprising the steps of (a) removing the chlorine-containing refrigerant from the refrigeration system while retaining a substantial portion of the lubricant in said system; and (b) introducing to said system a composition comprising: (i) a refrigerant; (ii) a surfactant; and (iii) a solubilizing agent.
    Type: Application
    Filed: August 30, 2001
    Publication date: April 25, 2002
    Inventors: Raymond Hilton Percival Thomas, Roy Phillip Robinson, Rajiv Ratna Singh, David Paul Wilson
  • Patent number: 6362153
    Abstract: Compositions of 1,1,1,3,3 -pentafluoropropane and 1,1 -dichloro-2,2,2-trifluoroethane are provided. The compositions of the invention are environmentally desirable for use as refrigerants, aerosol propellants, blowing agents for polymer foam, heat transfer media, gaseous dielectrics and solvents.
    Type: Grant
    Filed: December 20, 1999
    Date of Patent: March 26, 2002
    Assignee: Honeywell International Inc.
    Inventors: David Paul Wilson, Rajiv Ratna Singh, Ian Robert Shankland
  • Publication number: 20020003224
    Abstract: This invention relates to hydrofluorocarbons useful in refrigeration and heat pump applications. The invention provides hydrofluorocarbons selected from the group of 1,1,2,3,3-pentafluoropropane, 1,1,1,3,3-pentafluoropropane, 1,1,1,2,3-pentafluoropropane, and mixtures thereof that are environmentally suitable replacements for chlorofluorocarbons in refrigeration applications such as multi-stage centrifugal chillers.
    Type: Application
    Filed: April 23, 2001
    Publication date: January 10, 2002
    Inventors: H. Michael Hughes, Mark W. Spatz, Rajiv Ratna Singh
  • Publication number: 20020000534
    Abstract: The present invention provides refrigerant blends which are replacements for chlorodifluoromethane(HCFC-22). The present blends have refrigeration characteristics which are similar to HCFC-22. The blends comprise from about 10 to about 90 weight percent of a first component selected from the group consisting of 1,1,1-trifluoroethane, difluoromethane, propane, and mixtures thereof; from about 1 to about 50 weight percent of a second component selected from the group consisting of hydrofluorocarbon having 1 to 3 carbon atoms, fluorocarbon having 1 to 3 carbon atoms, inorganic compound, and mixtures thereof having a boiling point at atmospheric pressure in the range from about −90 degrees C. to less than −50 degrees C.; and from about 1 to about 50 weight percent of a third component which is hydrofluorocarbon having 1 to 3 carbon atoms, other than 1,1,1-trifluoroethane, having a boiling point at atmospheric pressure in the range from about −50 degrees C. to about −10 degrees C.
    Type: Application
    Filed: May 1, 2000
    Publication date: January 3, 2002
    Inventors: Robert G Richard, Ian Robert Shankland, Rajiv Ratna Singh, Michiel Jacques Van Nieuwstadt
  • Patent number: 6234352
    Abstract: A method and apparatus for storing and dispensing in liquid form a blend of fluids which normally fractionate upon boiling. The apparatus includes a container having an internal bladder dividing the container into two chambers. The first chamber contains the liquid blend, and the second chamber contains a pressurizing fluid in sufficient quantity to maintain the pressure on the other side of the bladder in the first chamber above the bubble point pressure of the liquid blend. In this manner, the vapor space above the fluid blend is eliminated, and thus the effect of fractionation caused by vaporization is essentially eliminated during dispensing or leakage of the blend from the package.
    Type: Grant
    Filed: August 10, 1999
    Date of Patent: May 22, 2001
    Assignee: AlliedSignal Inc.
    Inventors: Robert G. Richard, Rajiv Ratna Singh, H. Michael Hughes