Patents by Inventor Ramasamy Krishnan

Ramasamy Krishnan 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: 6444022
    Abstract: A water based offset lithographic ink comprising water; a modified rosin polymer comprised of resins soluble in water regardless of the pH of the water, resin rosin salts soluble in water at pH ranging from 7.5 to 10 and aqueous emulsion resins; a modified linseed oil; and pigment.
    Type: Grant
    Filed: May 20, 2000
    Date of Patent: September 3, 2002
    Assignee: Sun Chemical Corporation
    Inventors: Ramasamy Krishnan, Martin Thomas Czebotar, Hugo Babij
  • Publication number: 20020083865
    Abstract: A water-based lithographic ink composition is described, and contains water, a resin-bonded pigment; a nonionic surfactant, a rewetting agent, and a polymerizable surfactant. The nonionic surfactant is present in an amount such that the dynamic surface tension of the total composition is about 20 to about 40 dynes/cm. The polymerizable surfactant is present in an amount of about 0.5% by weight to about 2% by weight of the composition. The ink composition may also contain other, conventional ink component, as desired.
    Type: Application
    Filed: December 28, 2001
    Publication date: July 4, 2002
    Inventors: Ramasamy Krishnan, Martin Thomas Czebotar, Marilyn Yamat, Hugo Babij
  • Patent number: 6200372
    Abstract: A single fluid water-based offset lithographic news ink comprising water; a macromolecular resin binder comprised of a resin soluble in water regardless of the pH of the water, a rosin salt resin soluble in water at pH ranging from 7.5 to 10 and an aqueous emulsion polymer; pigment; a water dispersible soy bean based polymer; and a hydroxyethylehtylene urea re-wetting agent.
    Type: Grant
    Filed: December 16, 1999
    Date of Patent: March 13, 2001
    Assignee: Sun Chemical Corporation
    Inventors: Ramasamy Krishnan, Neil Young, Keqi Gan, Marilyn Yamat, Hugo Babij, Martin Thomas Czebotar
  • Patent number: 5972088
    Abstract: A single fluid water-based gravure printing ink comprising water; a macromolecular resin binder comprised of resins soluble in water regardless of the pH of the water; resins water soluble at water pH value ranging from 7.5 to 10; and aqueous emulsion resins; pigment; and a hydroxyethyl ethylene urea re-wetting agent.
    Type: Grant
    Filed: October 26, 1998
    Date of Patent: October 26, 1999
    Assignee: Sun Chemical Corporation
    Inventors: Ramasamy Krishnan, Marilyn C. Yamat, Sabino Apostol
  • Patent number: 5778789
    Abstract: An offset lithographic printing process comprising printing at a relative humidity of 75-90% utilizing a water-based, single fluid, fountain solution free, printing ink containing (a) a macromolecular binder composed of binders soluble in water regardless of the pH of the water; resin rosin salt binders soluble in water at a pH from 7.5 to 10; and aqueous emulsion binders; (b) pigment and; (c) a re-wetting agent.
    Type: Grant
    Filed: March 13, 1996
    Date of Patent: July 14, 1998
    Assignees: Sun Chemical, Heidelberg Harris
    Inventors: Ramasamy Krishnan, Marilyn C. Yamat, Hugo Babij, Roland T. Palmatier, Robert R. Murray
  • Patent number: 5725646
    Abstract: A water-based offset lithographic printing ink comprising 10-70 wt. % macromolecular binders comprising macromolecular binders soluble in water regardless of the pH; macromolecular rosin salt binders soluble in water at a pH ranging from 7.5 to 10; and macromolecular binders comprised of aqueous emulsions; pigment; and a hydroxyethylethylene urea re-wetting agent.
    Type: Grant
    Filed: March 13, 1996
    Date of Patent: March 10, 1998
    Assignee: Sun Chemical Corporation
    Inventors: Ramasamy Krishnan, Marilyn C. Yamat, Hugo Babij
  • Patent number: 5575843
    Abstract: A process for improving the color value of a pigment and for imparting stability to a water-based printing ink containing such pigment which comprises adding a polyester or polyether to the strike tank during the pigment conditioning step; the preferred polyether is methyl hydroxypropyl cellulose and the preferred polyester is benzoic acid-modified trimellitic anhydride polyester.
    Type: Grant
    Filed: December 16, 1994
    Date of Patent: November 19, 1996
    Assignee: Sun Chemical Corporation
    Inventors: Ramasamy Krishnan, Marilyn C. Yamat, Manuel Z. Gregorio, Russell J. Schwartz
  • Patent number: 5417749
    Abstract: A printing ink useful for "waterless" printing processes comprising a water-in-oil microemulsion wherein the water phase is present in an amount of about 5 to 20 wt. %, based on the weight of the ink. The water phase contains about 0.5 to 3 wt. %, based on the weight of the ink, of a surfactant which will not lower the surface tension (as measured at ambient temperature) of the ink, but will preferably increase the surface tension of the ink by at least about 5%. The ink optionally contains about 0.05 to 0.5 wt. %, based on the weight of the ink, of a water-soluble polymer capable of producing a viscosity in the water phase of about 5 to 10 poise as measured at ambient temperature.
    Type: Grant
    Filed: March 29, 1994
    Date of Patent: May 23, 1995
    Assignee: Sun Chemical Corporation
    Inventors: Ramasamy Krishnan, John M. Rooney, Robert W. Bassemir, Marilyn C. Yamat
  • Patent number: 5372635
    Abstract: A printing ink composition comprising:(a) a dispersion of about 10-25 wt. %, based on the weight of the composition, of a pigment in about 40-90 wt. %, based on the weight of the composition, of a C.sub.7 -C.sub.40 oil; and(b) about 0.1 to 5.0 wt. %, based on the weight of the composition, of a soap of a tall oil fatty acid.The printing ink composition has the unique capability of being utilized in lithographic printing processes utilizing tap water rather than aqueous fountain solution in the dampening system of the press.
    Type: Grant
    Filed: November 23, 1993
    Date of Patent: December 13, 1994
    Assignee: Sun Chemical Corporation
    Inventors: Olgierd Wasilewski, Richard R. Durand, Jr., Ramasamy Krishnan, Thi N. Do
  • Patent number: 5173111
    Abstract: Printing inks comprising a pigment and an aqueous or non-aqueous solvent (or a mixture of such solvents) have reduced abrasiveness towards printing surfaces (e.g. gravure printing cylinders) by incorporation in the ink of an alkoxylated dibasic phosphate ester and at least one alkali metal salt of a dialkylsulfosuccinic ester.
    Type: Grant
    Filed: November 18, 1991
    Date of Patent: December 22, 1992
    Assignee: Sun Chemical Corporation
    Inventors: Ramasamy Krishnan, Prasad K. Adhikari
  • Patent number: 5158606
    Abstract: A printing ink composition having a high degree of rub-off resistance comprising (a) a dispersion of a pigment in a vehicle containing a C.sub.7 -C.sub.40 oil and (b) a polymer latex emulsified in said dispersion. When employed for printing at high speeds, an anti-misting compound such as tridecyl acid phosphate, phosphoric acid, glycerol, or propylene carbonate is preferentially added to the ink composition. Where cost is not of paramount concern, a polytetrafluoroethylene wax is preferentially added to the ink composition.
    Type: Grant
    Filed: March 6, 1991
    Date of Patent: October 27, 1992
    Assignee: Sun Chemical Corporation
    Inventors: Daniel J. Carlick, Robert W. Bassemir, Ramasamy Krishnan, Richard R. Durand, Jr.
  • Patent number: 5098478
    Abstract: Water-based ink compositions comprising water, a pigment, a nonionic surfactant having a solubility in water of less than about 0.5 wt. % and a solubilizing agent sufficient to solubilize substantially all of the nonionic surfactant.
    Type: Grant
    Filed: December 7, 1990
    Date of Patent: March 24, 1992
    Assignee: Sun Chemical Corporation
    Inventors: Ramasamy Krishnan, Robert W. Bassemir, Timothy C. Vogel
  • Patent number: 5000787
    Abstract: A printing ink of low misting properties comprising a dispersion of a pigment in a vehicle containing a hydrocarbon oil and an antimisting additive comprising an organic acid phosphate such as tridecyl acid phosphate (which is preferred), glycerol or propylene carbonate.
    Type: Grant
    Filed: June 30, 1989
    Date of Patent: March 19, 1991
    Assignee: Sun Chemical Corporation
    Inventor: Ramasamy Krishnan
  • Patent number: 4990185
    Abstract: Glazing on printing press rollers is reduced by use of a lithographic printing ink containing a crown ether such as the cyclic polymeric hexamer of ethylene glycol. The incorporation of the crown ether in the ink is especially helpful in reducing glazing when using lithographic inks wherein the underlying pigment contains calcium, e.g. Calcium Lithol Rubine - Pigment Red 57:1.
    Type: Grant
    Filed: August 2, 1989
    Date of Patent: February 5, 1991
    Assignee: Sun Chemical Corporation
    Inventor: Ramasamy Krishnan
  • Patent number: 4854969
    Abstract: Lithographic fountain solutions containing water, one or more nonionic surfactants having an HLB in the range of 1 to 8 and one or more hydrotropes to maintain the surfactant in solution without increasing the HLB of the fountain solution.
    Type: Grant
    Filed: February 26, 1988
    Date of Patent: August 8, 1989
    Assignee: Sun Chemical Corporation
    Inventors: Robert Bassemir, Ramasamy Krishnan, Arthur I. Lowell