Patents by Inventor Janice S. Sprague

Janice S. Sprague 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).

  • Asphalt compositions
    Patent number: 4571269
    Abstract: Addition of selected dispersants comprising metal petroleum sulfurates and selected oil-soluble esters to asphaltic fractions exhibiting a positive Oliensis spot test to improve the properties thereof so that the asphaltic material will pass the Oliensis spot test and be suitable for use in paving formulations.
    Type: Grant
    Filed: March 31, 1981
    Date of Patent: February 18, 1986
    Assignee: Phillips Petroleum Company
    Inventors: Jack N. Finch, Janice S. Sprague