Patents by Inventor S. A. Ravishankar

S. A. Ravishankar 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).

  • Process and reagent for separating finely divided titaniferrous impurities from Kaolin
    Patent number: 7393462
    Abstract: A mineral beneficiating reagent containing an alkyl hydroxamic acid or salt thereof and a nonionic surfactant. The alkyl hydroxamic acid or a salt thereof is represented by the formula: R—C(?O)N(R?)—OM, wherein R is linear or branched C2-C18 alkyl, linear or branched C2-C18 alkenyl, C6-C20 aryl or substituted aryl, C7-C26 aralkyl or substituted aralkyl; R? is H, C1-C12 alkyl or aralkyl; M is hydrogen, an alkali metal, or an ammonium cation represented by N+(A,B,C,D) wherein each of A,B,C,D, respectively, are H or C1-C6 alkyl or benzyl radicals. The nonionic surfactant can be any known nonionic surfactant, including but not limited ethoxylated alcohols, esters, ethoxylated acids, ethoxylated (alkyl) phenols, alcanolamides, polyethylene oxide copolymers and mixtures thereof.
    Type: Grant
    Filed: May 13, 2004
    Date of Patent: July 1, 2008
    Assignee: Cytec Technology Corp.
    Inventors: Abdul Gorken, Lino G. Magliocco, D. R. Nagaraj, Alan S. Rothenberg, S. A. Ravishankar
  • Composite pigments comprising in-situ precipitated metal carbonate crystals
    Patent number: 6440209
    Abstract: Composite pigments comprising particles of silicate or oxide minerals having deposited thereon a multiplicity of particles of a metal carbonate as a result of in-situ precipitation.
    Type: Grant
    Filed: February 9, 2000
    Date of Patent: August 27, 2002
    Assignee: Engelhard Corpoartion
    Inventors: S. A. Ravishankar, Ernest M. Finch, Richard R. Berube