Patents by Inventor Hendrik Tijmen Verkouw

Hendrik Tijmen Verkouw 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).

  • Polyolefin-substituted dicarboxylic derivatives
    Patent number: 6268439
    Abstract: Polyolefin-substituted dicarboxylic ester derivatives, having an ester group derived from a polyether polyol and process for making such; wherein the ester derivatives are useful additives in lubricating oil compositions and concentrates thereof.
    Type: Grant
    Filed: January 14, 1999
    Date of Patent: July 31, 2001
    Assignee: Shell Oil Company
    Inventors: Michael Thomas Clark, Indu Sawhney, Hendrik Tijmen Verkouw
  • Polyolefin-substituted dicarboxylic derivatives
    Patent number: 5900466
    Abstract: Polyolefin-substituted dicarboxylic ester derivatives, having an ester group derived from a polyether polyol and process for making such; wherein the ester derivatives are useful additives in lubricating oil compositions and concentrates thereof.
    Type: Grant
    Filed: August 8, 1996
    Date of Patent: May 4, 1999
    Assignee: Shell Oil Company
    Inventors: Michael Thomas Clark, Indu Sawhney, Hendrik Tijmen Verkouw
  • Alkenyl-substituted dicarboxylic derivatives
    Patent number: 5736492
    Abstract: The invention provides alkenyl-substituted dicarboxylic derivatives, having (a) an alkenyl group derived from an atactic propylene oligomer substantially of the formula ##STR1## where n is in the range 15 to 120, having number average molecular weight (M.sub.n) in the range 700 to 5000, and molar ratio dicarboxylic moieties to atactic propylene oligomer in the range 1:1 to 1.5:1; and having (b) an ester group derived from a polyol, which are useful as dispersant additives; a process for making the ester derivatives, additive concentrates containing such ester derivatives, and lubricating oil compositions.
    Type: Grant
    Filed: August 2, 1996
    Date of Patent: April 7, 1998
    Assignee: Shell Oil Company
    Inventors: Michael Thomas Clark, Hendrik Tijmen Verkouw