Patents by Inventor Douglas Darr

Douglas Darr 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).

  • Stable ascorbic acid compositions
    Patent number: 5140043
    Abstract: Stable topical aqueous compositions are provided containing a concentration of L-ascorbic acid above about 1% (W/V) and maintaining a pH below about 3.5.
    Type: Grant
    Filed: April 17, 1989
    Date of Patent: August 18, 1992
    Assignee: Duke University
    Inventors: Douglas Darr, Sheldon R. Pinnell