Patents by Inventor Dipak Shah

Dipak Shah 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: 6057388
    Abstract: A process of preparing a concentrate which is useful as a thickener for aqueous compositions is provided. The process comprises obtaining a solution of an associative thickener compound in an organic solvent capable of forming a low boiling azeotrope with water. The solution is essentially free of water at this point and is at a temperature above the boiling point of said low boiling azeotrope. Water is added to said solution and an azeotrope of water and said organic solvent is distilled. The rate of addition of water is sufficient to replace said azeotrope with water, but is insufficient to cause a second phase to form in the resulting mixture of said solution and said water. The process yields a concentrate of an associative thickener in water, which concentrate is essentially free of volatile organic solvents.
    Type: Grant
    Filed: January 20, 1999
    Date of Patent: May 2, 2000
    Assignee: Henkel Corporation
    Inventors: Michael Wiggins, Dipak Shah, Reuben H. Grinstein
  • Patent number: 5916935
    Abstract: A process of preparing a concentrate which is useful as a thickener for aqueous compositions is provided. The process comprises obtaining a solution of an associative thickener compound in an organic solvent capable of forming a low boiling azeotrope with water. The solution is essentially free of water at this point and is at a temperature above the boiling point of said low boiling azeotrope. Water is added to said solution and an azeotrope of water and said organic solvent is distilled. The rate of addition of water is sufficient to replace said azeotrope with water, but is insufficient to cause a second phase to form in the resulting mixture of said solution and said water. The process yields a concentrate of an associative thickener in water, which concentrate is essentially free of volatile organic solvents.
    Type: Grant
    Filed: July 28, 1997
    Date of Patent: June 29, 1999
    Assignee: Henkel Corporation
    Inventors: Michael Wiggins, Dipak Shah, Reuben H. Grinstein