Patents by Inventor Pravin K. Kukkala

Pravin K. Kukkala 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: 6291580
    Abstract: A polyurethane, soluble or dispersible in water, prepared from organic diisocyanate diols or other isocyanate reactive materials and a 2,2-hydroxymethyl-substituted carboxylic acid diol neutralized with a cosmetically acceptable organic or inorganic base and formulated into a hair fixative composition containing low amounts of volatile organic solvent. The present invention is also directed to a process for the preparation of polyurethanes comprising dispersing the polyurethane after at least 70% of the theoretical isocyanate reaction has taken place, but before completion of the reaction.
    Type: Grant
    Filed: June 25, 1999
    Date of Patent: September 18, 2001
    Assignee: National Starch and Chemical Investment Holding Corporation
    Inventors: Pravin K. Kukkala, Sharon P. Lee, Andrew J. Kielbania, Jr., Melissa J. Vitale
  • Patent number: 5968494
    Abstract: A polyurethane, soluble or dispersible in water, prepared from organic diisocyanate diols or other isocyanate reactive materials and a 2,2-hydroxymethyl-substituted carboxylic acid diol neutralized with a cosmetically acceptable organic or inorganic base and formulated into a hair fixative composition containing low amounts of volatile organic solvent. The present invention is also directed to a process for the preparation of polyurethanes comprising dispersing the polyurethane after at least 70% of the theoretical isocyanate reaction has taken place, but before completion of the reaction.
    Type: Grant
    Filed: February 24, 1998
    Date of Patent: October 19, 1999
    Assignee: National Starch and Chemical Investment Holding Corporation
    Inventors: Pravin K. Kukkala, Sharon P. Lee, Andrew J. Kielbania, Jr., Melissa J. Vitale
  • Patent number: 5859111
    Abstract: A process is described for preparing aqueous polymeric dispersions of a dispersion of an interpenetrated polymer of a hydrophobic polyurethane and a polymer prepared from ethylenically unsaturated monomers, and optionally a dispersion of another monomer that will enhance the performance of the interpenetrated polymer.
    Type: Grant
    Filed: December 18, 1996
    Date of Patent: January 12, 1999
    Assignee: National Starch and Chemical Investment Holding Corporation
    Inventors: Pravin K. Kukkala, Andrew J. Kielbania, Osamu Futakuchi
  • Patent number: 5717024
    Abstract: A process for preparing aqueous dispersions of polyurethanes comprises dispersing polyurethane prepolymer containing unreacted --NCO functionality in water with moderate agitation at a temperature at or below 65.degree. C., preferably at or below 38.degree. C., and more preferably within the range 38.degree.-25.degree. C.; simultaneously reducing the agitation to a mild rate and maintaining the temperature within the range 38.degree.-85.degree. C., preferably, 60.degree.-65.degree. C., until the reaction of --NCO with water levels off; adding an effective amount of a quenching agent to react with sufficient --NCO functionality to reduce the number of available --NCO groups that can react with water so that the evolution of CO.sub.2 is reduced or eliminated during storage of the polyurethane dispersion; and at any of the previous sequential steps adding an effective amount of a deaerating agent to reduce or eliminate CO.sub.2 foaming or to liberate any dissolved CO.sub.2 gas.
    Type: Grant
    Filed: February 23, 1996
    Date of Patent: February 10, 1998
    Assignee: National Starch and Chemical Investment Holding Corporation
    Inventors: Pravin K. Kukkala, Andrew J. Kielbania, Andrew P. Full, Antonios Tontisakis
  • Patent number: 5571860
    Abstract: An emulsion adhesion composition comprising a polyvinyl alcohol stabilized polymer emulsion; the polymer comprising 40 to 94.5% by weight of a vinyl ester of an C.sub.1 -C.sub.13 alkanoic acid, 5 to 40% by weight ethylene and 0.5 to 10% by weight N-vinyl formamide or N-vinyl pyrrolidone, the adhesive being characterized by superior adhesion and heat resistance.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: November 5, 1996
    Assignee: National Starch and Chemical Investment Holding Corporation
    Inventors: Pravin K. Kukkala, Malcolm F. Hallam, M. Erin Jones, Richard K. Vetterl
  • Patent number: 5434216
    Abstract: Water resistant emulsions for woodworking adhesives may be prepared using an emulsion polymer, the polymer being prepared in the presence of 1 to 2.5% by weight of 88% hydrolyzed polyvinyl alcohol and 1 to 4% by weight of 95-99.5% (or above) hydrolyzed polyvinyl alcohol.
    Type: Grant
    Filed: May 7, 1993
    Date of Patent: July 18, 1995
    Assignee: National Starch and Chemical Investment Holding Corporation
    Inventors: Paul R. Mudge, Pravin K. Kukkala, John Walker
  • Patent number: 5278211
    Abstract: Formaldehyde free crosslinking emulsion polymers are prepared by the addition of N-(2,2-dialkoxy-1-hydroxy)ethyl acrylamide to a vinyl ester based polymer. The resultant emulsions can be used as binders for nonwovens or fiberfill or as woodworking adhesives.
    Type: Grant
    Filed: April 5, 1993
    Date of Patent: January 11, 1994
    Assignee: National Starch and Chemical Investment Holding Corporation
    Inventors: Rama S. Chandran, Carmine P. Iovine, Paul R. Mudge, John C. Leighton, Pravin K. Kukkala
  • Patent number: 5252663
    Abstract: Formaldehyde free crosslinking emulsion polymers are prepared by the addition of N-(2,2-dialkoxy-1-hydroxy)ethyl acrylamide to a vinyl ester based polymer. The resultant emulsions can be used as binders for nonwovens or fiberfill or as woodworking adhesives.
    Type: Grant
    Filed: May 22, 1991
    Date of Patent: October 12, 1993
    Assignee: National Starch and Chemical Investment Holding Corporation
    Inventors: Rama S. Chandran, Carmine P. Iovine, Paul R. Mudge, John C. Leighton, Malcolm F. Hallam, Pravin K. Kukkala