Patents by Inventor Karikath Sukumar Varma

Karikath Sukumar Varma 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).

  • Fire Resistant Glazing
    Publication number: 20090317618
    Abstract: Fire resistant glazings comprise a fire resistant interlayer based upon a silicate waterglass are characterised by the incorporation of aluminium ions. The aluminate is incorporated as a solution which has been partially neutralised using hydroxycarboxylic acid which is preferably citric acid. The incorporation of aluminium provides glazings have improved fire resistance and impact properties.
    Type: Application
    Filed: September 1, 2009
    Publication date: December 24, 2009
    Inventors: Karikath Sukumar Varma, John Richard Holland, David William Holden, Stephen Ian Bond
  • Production of fire resistant laminates
    Patent number: 7334435
    Abstract: Process for the production of an intumescent fire resistant layer by drying a waterglass solution on the surface of a glass substrate are carried out in the presence of a salt of a carbonic acid or an ?-hydroxy carboxylic acid such as potassium citrate. The drying is preferably carried out at a rate which reduces of pH of the solution by no more than 2 units during an initial drying period of 5 hours. The resulting interlayers provide improved fire resistance.
    Type: Grant
    Filed: September 17, 2001
    Date of Patent: February 26, 2008
    Assignee: Pilkington plc
    Inventors: Karikath Sukumar Varma, John Richard Holland, David William Holden
  • Fire resistant glazings
    Patent number: 7282092
    Abstract: Novel waterglass compositions comprise a zirconium containing anionic aggregate, preferably potassium zirconium carbonate or ammonium zirconium carbonate, in a quantity sufficient to provide at least 0.5% as zirconium metal. The compositions can be dried and/or gelled to form optically clear interlayers useful in the production of fire resistant glass laminates. The incorporation of the zirconium containing aggregate improves the fire resistant performance of the laminates.
    Type: Grant
    Filed: June 7, 2005
    Date of Patent: October 16, 2007
    Assignee: Pilkington PLC
    Inventors: John Richard Holland, Karikath Sukumar Varma, David William Holden
  • Fire resistant glazings
    Patent number: 7189285
    Abstract: Solutions comprising a sodium silicate waterglass having a modulus of less than 3 and at least 8% by weight of an organic polyhydroxy compound such as glycerol are useful in the production of interlayers used in fire resistant glass laminates. The solutions are dried on a flat surface such as glass to produce a clear intumescent interlayer having improved impact resistance. The dried interlayer may be removed from the surface in the form of an elastomeric material which may also be used as an interlayer in a fire resistant glazing.
    Type: Grant
    Filed: March 16, 2001
    Date of Patent: March 13, 2007
    Assignee: Pilkington PLC
    Inventors: John Richard Holland, Karikath Sukumar Varma, David William Holden
  • Fire resistant glazings
    Patent number: 6929691
    Abstract: Novel waterglass compositions comprise a zirconium containing anionic aggregate, preferably potassium zirconium carbonate or ammonium zirconium carbonate, in a quantity sufficient to provide at least 0.5% as zirconium metal. The compositions can be dried and/or gelled to form optically clear interlayers useful in the production of fire resistant glass laminates. The incorporation of the zirconium containing aggregate improves the fire resistant performance of the laminates.
    Type: Grant
    Filed: August 1, 2000
    Date of Patent: August 16, 2005
    Assignee: Pilkington plc
    Inventors: John Richard Holland, Karikath Sukumar Varma, David William Holden
  • Production of fire resistant laminates
    Publication number: 20030186063
    Abstract: Process for the production of an intumescent fire resistant layer by drying a waterglass solution on the surface of a glass substrate are carried out in the presence of a salt of a carbonic acid or an &agr;-hydroxy carboxylic acid such as potassium citrate. The drying is preferably carried out at a rate which reduces of pH of the solution by no more than 2 units during an initial drying period of 5 hours. The resulting interlayers provide improved fire resistance.
    Type: Application
    Filed: March 13, 2003
    Publication date: October 2, 2003
    Inventors: Karikath Sukumar Varma, John Richard Holland, David William Holden
  • Fire resistant glazings
    Publication number: 20030180543
    Abstract: Solutions comprising a sodium silicate waterglass having a modulus of less than 3 and at least 8% by weight of an organic polyhydroxy compound such as glycerol are useful in the production of interlayers used in fire resistant glass laminates. The solutions are dried on a flat surface such as glass to produce a clear intumescent interlayer having improved impact resistance. The dried interlayer may be removed from the surface in the form of an elastomeric material which may also be used as an interlayer in a fire resistant glazing.
    Type: Application
    Filed: September 17, 2002
    Publication date: September 25, 2003
    Inventors: John Richard Holland, Karikath Sukumar Varma, David William Holden
  • Boroxine compositions
    Patent number: 6335423
    Abstract: A boroxine composition having fire and/or flame retardant properties comprising a halo-substituted boroxine in combination with a compound containing an epoxide group curable by the halogenated boroxine compound. A method of making the boroxine comprises reacting the appropriate alcohol with boric acid in the presence of a solvent, usually toluene. In an alternative method, the boroxine is prepared by reacting boric oxide with the corresponding borate, the latter being prepared by reacting the corresponding alcohol with boron trichloride.
    Type: Grant
    Filed: September 20, 1999
    Date of Patent: January 1, 2002
    Assignee: Pilkington PLC
    Inventor: Karikath Sukumar Varma