Patents by Inventor Ramesh C. Kumar

Ramesh C. Kumar 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: 6219121
    Abstract: In an acrylonitrile based retarder, relatively uniform performance is obtained as the angle of incidence varies over a wide range. A toughening material may be blended with an acrylonitrile based polymer to facilitate processing of a retarder and improve mechanical properties of the retarder without compromising the optical performance. A rubber-modified acrylonitrile based retarder which provides relatively uniform wide angle can be fabricated using conventional processing techniques. Such retarders are particularly suited for a number of specific applications which use relatively wide ranges of incidence angles.
    Type: Grant
    Filed: December 10, 1998
    Date of Patent: April 17, 2001
    Assignee: 3M Innovative Properties Company
    Inventors: Hassan Sahouani, Sundaravel Damodaran, Gary T. Boyd, Ramesh C. Kumar
  • Patent number: 6139966
    Abstract: The invention provides novel macromonomer and carboxyl functional polyurethanes having a high carboxyl content. The invention further provides dispersions, coatings and magnetic recording media comprising these polyurethanes, or blends or copolymers of these polyurethanes with quaternary ammonium compounds. The invention further provides novel dispersions, coatings and magnetic recording media comprising combinations of carboxyl functional polyurethanes having a high carboxyl content with quaternary ammonium polymers.
    Type: Grant
    Filed: August 10, 1998
    Date of Patent: October 31, 2000
    Assignee: Imation Corp.
    Inventors: James G. Carlson, Jeffrey T. Anderson, Ramesh C. Kumar, Alvin M. Berg
  • Patent number: 6132844
    Abstract: An adhesive backed article, method for its manufacture and a kit including such an article are provided. The article of the invention is provided as an antislip product comprised of a backing and an oil resistant adhesive applied to a major surface of the backing. In one aspect of the invention, an article is provided comprising: a backing having a first and second major surfaces, the first major surface being textured to provide a slip resistant surface; and a pressure sensitive adhesive disposed on the second major surface of the backing, the adhesive formulated to be resistant to peel in use when exposed to oily environments, the adhesive comprising the polymerized reaction product of (a) acrylic acid; (b) at least one N-vinyl containing monomer; (c) at least one acrylate selected from the group consisting of isooctyl acrylate, 2-ethylhexyl acrylate, and combinations thereof; (d) optionally, less than about 20 weight % fluoroalkyl siloxane; and (e) optionally, a cross linking agent.
    Type: Grant
    Filed: December 11, 1997
    Date of Patent: October 17, 2000
    Assignee: 3M Innovative Properties Company
    Inventors: Gordon L. Altshuler, Ramesh C. Kumar
  • Patent number: 5874144
    Abstract: The present invention provides a novel silicone free copolymer and coating prepared therefrom. The coating which is capable of being written on effectively with both solvent-based and water-based inks is also bleedthrough resistant. A repositionable pressure sensitive adhesive note is capable of effectively adhering to the coating. The invention also provides substrates coated with the coatings and articles such as pads and rolls formed from the coated substrates.
    Type: Grant
    Filed: October 23, 1996
    Date of Patent: February 23, 1999
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Ramesh C. Kumar, Shari J. Cullen
  • Patent number: 5867239
    Abstract: In an acrylonitrile based retarder, relatively uniform performance is obtained as the angle of incidence varies over a wide range. A toughening material may be blended with an acrylonitrile based polymer to facilitate processing of a retarder and improve mechanical properties of the retarder without compromising the optical performance. A rubber-modified acrylonitrile based retarder which provides relatively uniform wide angle can be fabricated using conventional processing techniques. Such retarders are particularly suited for a number of specific applications which use relatively wide ranges of incidence angles.
    Type: Grant
    Filed: October 17, 1997
    Date of Patent: February 2, 1999
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Hassan Sahouani, Sundaravel Damodaran, Gary T. Boyd, Ramesh C. Kumar
  • Patent number: 5744207
    Abstract: An article that is capable of accepting and anchoring printed indicia and yet, maintains good release properties. The article of the present invention is coated with a release agent on a substrate such as paper. Release coatings receptive to toner particles emitted by electrophotoconductive devices comprise a polymer having at least one vinyl polymeric segment having a T.sub.g between -10.degree. C. and 65.degree. C. and at least one siloxane polymeric segment.
    Type: Grant
    Filed: November 21, 1996
    Date of Patent: April 28, 1998
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Joseph T. Bartusiak, Steven S. Kantner, Ramesh C. Kumar, Timothy A. Mertens
  • Patent number: 5725882
    Abstract: Cosmetic compositions are provided containing vinyl-silicone graft or block copolymers of the formula ##STR1##
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: March 10, 1998
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Kanta Kumar, Ramesh C. Kumar, Smarajit Mitra
  • Patent number: 5716685
    Abstract: The present invention provides a novel copolymer and coating prepared therefrom. The coating which is capable of being written on effectively with both solvent-based and water-based inks is also bleedthrough resistant. A repositionable pressure sensitive adhesive note is capable of effectively adhering to the coating. The invention also provides substrates coated with the coatings and articles such as pads formed from the coated substrates.
    Type: Grant
    Filed: October 23, 1996
    Date of Patent: February 10, 1998
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Ramesh C. Kumar, Shari J. Cullen
  • Patent number: 5712345
    Abstract: A polymeric binder system useful for a magnetic recording medium, the polymeric binder system and comprising a hard resin component comprising a nonhalogenated vinyl copolymer and a soft resin component comprising a polyurethane having a phosphonate diester group. The binder system is useful for preparing the magnetic layer and/or backside coating of magnetic recording media, in order to provide media that demonstrate an improved combination of such as modulus, Tg, and smoothness.
    Type: Grant
    Filed: November 12, 1996
    Date of Patent: January 27, 1998
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Ruth M. Erkkila, James G. Carlson, Christopher M. Evans, James A. Greczyna, Ramesh C. Kumar, Colin F. Norman, Nelson T. Rotto
  • Patent number: 5679752
    Abstract: A magnetic recording medium, comprising a magnetic layer provided on a nonmagnetizable substrate, wherein the magnetic layer comprises a magnetic pigment dispersed in a polymeric binder, the polymeric binder comprising a resin, wherein the resin comprises a nonchlorinated fluorine-containing vinyl copolymer having pendant nitrile groups, pendant hydroxyl groups, and pendant fluorine-containing groups.
    Type: Grant
    Filed: January 29, 1996
    Date of Patent: October 21, 1997
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Ravindra L. Arudi, Ramesh C. Kumar
  • Patent number: 5674604
    Abstract: The present invention provides a non-halogenated vinyl oligomer wherein the oligomer comprises a plurality of pendant nitrile groups and at least one pendant dispersing group; wherein the oligomer has a glass transition temperature of about 60.degree. to about 105.degree. C. and a number average molecular weight of about 2000 to about 4000 and the equivalent weight of the dispersing group(s) is about 500 to about 50,000. The invention also provides magnetic recording media comprising these dispersants.
    Type: Grant
    Filed: March 31, 1995
    Date of Patent: October 7, 1997
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Ramesh C. Kumar, Suman K. Patel
  • Patent number: 5635331
    Abstract: Blocking is substantially reduced between individual sheets having a thermal adhesive coated thereon by including a release agent with the thermal adhesive. Preferred release agents are materials which have previously been used as low-adhesion backsize (LAB) coatings in pressure-sensitive adhesive applications.
    Type: Grant
    Filed: October 13, 1994
    Date of Patent: June 3, 1997
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Steven L. Kangas, Charles W. Graves, Ramesh C. Kumar
  • Patent number: 5578548
    Abstract: A thermographic element containing: (a) a substrate; (b) an image-forming layer coated onto the substrate; and (c) overlaying the image-forming layer, a topcoat layer composed of the reaction product of (1) a polymer composed of interpolymerized units derived from: (i) about 45-65 wt % of vinyl-substituted aromatic monomer; (ii) about 15-30 wt % vinyl monomer containing a pendant nitrile group; (iii) about 5-30 wt % hydroxyl-containing; ethylenically-unsaturated monomer; and (2) a suitable crosslinking agent. A slip agent is optionally used. The topcoat layer provides a thermographic element with high gloss in the imaged areas; has excellent runnability with no chatter in the feed direction of the element; and exhibits no removal of topcoat which prevents formation of printhead-created voids in the imaged areas.
    Type: Grant
    Filed: October 16, 1995
    Date of Patent: November 26, 1996
    Assignee: Minnesota Mining & Manufacturing Company
    Inventors: Jon A. Bjork, Ramesh C. Kumar, John C. Haidos
  • Patent number: 5510187
    Abstract: Magnetic recording medium, comprising a magnetic layer provided on a nonmagnetizable substrate, wherein the magnetic layer comprises a magnetic pigment dispersed in a polymeric binder. The polymeric binder comprises a nonhalogenated vinyl copolymer, wherein the vinyl copolymer comprises a plurality of pendant nitrile groups, a plurality of pendant hydroxyl groups, and at least one pendant dispersing group. Preferably, the binder also includes a secondary polymer component.
    Type: Grant
    Filed: June 1, 1995
    Date of Patent: April 23, 1996
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Ramesh C. Kumar, Ravindra L. Arudi, James G. Carlson, Daniel Y. Chang, John C. Haidos, Keith J. Modert, Suman K. Patel, Nelson T. Rotto
  • Patent number: 5501903
    Abstract: A polymeric binder system useful for a magnetic recording medium, the polymeric binder system and comprising a hard resin component comprising a nonhalogenated vinyl copolymer and a soft resin component comprising a polyurethane having a phosphonate diester group. The binder system is useful for preparing the magnetic layer and/or backside coating of magnetic recording media, in order to provide media that demonstrate an improved combination of such as modulus, Tg, and smoothness.
    Type: Grant
    Filed: July 29, 1994
    Date of Patent: March 26, 1996
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Ruth M. Erkkila, James G. Carlson, Christopher M. Evans, James A. Greczyna, Ramesh C. Kumar, Colin F. Norman, Nelson T. Rotto
  • Patent number: 5496635
    Abstract: A directly printable composition is provided. The composition is the reaction product of a vinyl-functional monomer, a chlorinated olefinic resin, optionally an amide-functional monomer, and optionally a free radically polymerizable silicone-containing material. The reaction product is stable and can be applied to a variety of substrates. A variety of inks can be directly printed on the coating.
    Type: Grant
    Filed: March 1, 1994
    Date of Patent: March 5, 1996
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Robert C. Francis, Robert R. L. Smolders, William G. Walsh, Ramesh C. Kumar
  • Patent number: 5492599
    Abstract: Treated cellulose-based substrate, e.g., paper, having improved release properties and methods of making such treated substrate are disclosed. The treated substrate is coated with a primer coating comprising a cationic polymer and with a release coating comprising a carboxy- or carboxylate-containing release polymer.
    Type: Grant
    Filed: May 18, 1994
    Date of Patent: February 20, 1996
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Christopher C. Olson, Ramesh C. Kumar, John C. Chang
  • Patent number: 5482991
    Abstract: Novel pressure-sensitive adhesives are described which show significant resistance to solvents and working fluids such as jet fuel, hydraulic fluid, de-icing fluid and the like. Adhesive compositions comprise nonaqueous dispersions of copolymers of acrylic monomers prepared in the presence of a vinyl-substituted fluoroalkyl siloxane having the general formula I and a macromonomeric stabilizer. The adhesives prepared from the adhesive compositions exhibit excellent adhesion to glass, aluminum, and low surface-energy materials such as fluoroalkyl siloxane elastomers.
    Type: Grant
    Filed: September 16, 1994
    Date of Patent: January 9, 1996
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Ramesh C. Kumar, Albert I. Everaerts, Yvan A. Bogaert
  • Patent number: 5468477
    Abstract: Cosmetic compositions are provided containing vinyl-silicone graft or block copolymers of the formula ##STR1##
    Type: Grant
    Filed: August 3, 1993
    Date of Patent: November 21, 1995
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Kanta Kumar, Ramesh C. Kumar, Smarajit Mitra
  • Patent number: 5349004
    Abstract: Novel pressure-sensitive adhesives are described which show significant resistance to solvents and working fluids such as jet fuel, hydraulic fluid, de-icing fluid and the like. Adhesive compositions comprise nonaqueous dispersions of copolymers of acrylic monomers prepared in the presence of a vinyl-substituted fluoroalkyl siloxane having the general formula I and a macromonomeric stabilizer. The adhesives prepared from the adhesive compositions exhibit excellent adhesion to glass, aluminum, and low surface-energy materials such as fluoroalkyl siloxane elastomers.
    Type: Grant
    Filed: September 18, 1992
    Date of Patent: September 20, 1994
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Ramesh C. Kumar, Albert I. Everaerts, Yvan A. Bogaert