Patents by Inventor Sharad Ramanlal Thakkar

Sharad Ramanlal Thakkar 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).

  • Pigment ink formulation
    Patent number: 6585818
    Abstract: The invention provides an improved ink formulation and method therefore. The formulation includes from about 50 to about 85 percent by weight water, humectant and an organic solvent and a chemically modified carbon black pigment, wherein the chemically modified carbon black pigment contains steric inducing groups on a surface of the carbon black which groups are derived from a steric inducing compound which compound is substantially soluble in the humectant and is reactive with an organic acid halide. The ink jet printer ink formulation containing the chemically modified carbon black has an idle time of greater than about 15 seconds in an ink jet printhead. Improved idle time is important because it reduces nozzle plugging between nozzle firings.
    Type: Grant
    Filed: August 6, 2001
    Date of Patent: July 1, 2003
    Assignee: Lexmark International, Inc.
    Inventors: Sharad Ramanlal Thakkar, Jing X. Sun
  • PIGMENT INK FORMULATION
    Publication number: 20030101900
    Abstract: The invention provides an improved ink formulation and method therefore. The formulation includes from about 50 to about 85 percent by weight water, humectant and an organic solvent and a chemically modified carbon black pigment, wherein the chemically modified carbon black pigment contains steric inducing groups on a surface of the carbon black which groups are derived from a steric inducing compound which compound is substantially soluble in the humectant and is reactive with an organic acid halide. The ink jet printer ink formulation containing the chemically modified carbon black has an idle time of greater than about 15 seconds in an ink jet printhead. Improved idle time is important because it reduces nozzle plugging between nozzle firings.
    Type: Application
    Filed: August 6, 2001
    Publication date: June 5, 2003
    Inventors: Sharad Ramanlal Thakkar, Jing X. Sun