Patents by Inventor Roopram Ramharack

Roopram Ramharack 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).

  • Radiation cured hot melt pressure sensitive adhesives from photoinitiator-functionalized, crosslinkable copolymers
    Patent number: 5536759
    Abstract: This invention is a hot melt pressure sensitive adhesive formed by copolymerizing acrylic, or a combination of acrylic and vinyl, monomers, at least one of which is a photoinitiator, with the functional monomer, 1-(1-isocyanato-1-methyl ethyl)-3-(1-methyl ethenyl)benzene (m-TMI), to give a saturated polymer with pendant vinyl groups that are crosslinked by UV radiation.
    Type: Grant
    Filed: October 13, 1994
    Date of Patent: July 16, 1996
    Assignee: National Starch and Chemical Investment Holding Corporation
    Inventors: Roopram Ramharack, Rama Chandran
  • Radiation curable hot melt pressure sensitive adhesives
    Patent number: 5416127
    Abstract: This invention is a hot melt pressure sensitive adhesive formed by copolymerizing acrylic, or a combination of acrylic and vinyl, monomers with the functional monomer, 1-(1-isocyanato-1-methyl ethyl)-3-(1-methyl ethenyl)benzene m-TMI, to give a saturated polymer with pendant vinyl groups that are crosslinked by UV or EB radiation.
    Type: Grant
    Filed: January 26, 1994
    Date of Patent: May 16, 1995
    Assignee: National Starch and Chemical Investment Holding Corporation
    Inventors: Rama Chandran, Roopram Ramharack, Irwin J. Davis, John C. Leighton
  • Process of preparing hot melt pressure sensitive adhesives on a substrate
    Patent number: 5391406
    Abstract: This invention is a hot melt pressure sensitive adhesive formed by copolymerizing acrylic, or a combination of acrylic and vinyl, monomers, at least one of which is a photoinitiator, with the functional monomer, 1-(1-isocyanato-1methyl ethyl)-3-(1-methyl ethenyl)benzene (m-TMI), to give a saturated polymer with pendant vinyl groups that are crosslinked by UV radiation.
    Type: Grant
    Filed: March 25, 1994
    Date of Patent: February 21, 1995
    Assignee: National Starch and Chemical Investment Holding Corporation
    Inventors: Roopram Ramharack, Rama Chandran
  • Photopolymerizable composition for cladding optical fibers
    Patent number: 5024507
    Abstract: A photopolymerizable composition for cladding optical fibers comprises an unsubstituted or fluorosubstituted diacrylate monomer; a fluorinated monofunctional acrylate monomer in an amount of from about 2 to about 12 parts by weight per part by weight of the diacrylate monomer; a photoinitiator; and a viscosity modifying agent to increase the viscosity of the composition to about 1000 to about 15000 cP. Upon photocuring, the composition has a refractive index not greater than about 1.43, and preferably not greater than about 1.40.
    Type: Grant
    Filed: May 10, 1990
    Date of Patent: June 18, 1991
    Assignee: Polaroid Corporation
    Inventors: Richard A. Minns, Iris B. K. Bloom, Roopram Ramharack
  • Magnetic recording media and a method using a stable fluid reactive dispersion in preparing magnetic recording media
    Patent number: 4876149
    Abstract: A magnetic recording medium is provided with a layer comprised of finely divided particles dispersed in a binder comprised of a particular crosslinked dispersing polymer based on a vinyl aromatic monomer and having a degree of polymerization greater than about 100. The layer may be on a flexible, semi-rigid, or rigid support base. A stable-fluid, reactive dispersion of finely divided magnetic particles in a crosslinked dispersing polymer having a degree of polymerization greater than 100 which can be mixed with a crosslinker to provide a curable composition useful in preparing the magnetic recording medium. The curable composition also preferably contains multi-hydroxyl-functional polyurethane as a soft-component contributing cobinder resin.
    Type: Grant
    Filed: July 31, 1986
    Date of Patent: October 24, 1989
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Roopram Ramharack