Patents by Inventor Rolf Schwindt

Rolf Schwindt 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).

  • Subpigmentary titanium dioxide with improved photostability
    Patent number: 5451252
    Abstract: Subpigmentary titanium dioxide with decreased photoactivity is produced if known ions for increasing photostability in titanium dioxide pigments are not deposited on the surface of the subpigmentary particles, but instead are included intracrystallinely in the pigment particle (i.e., doped). In a preferred process for preparation of doped subpigmentary titanium dioxide particles, an acid solution containing the dopant is added in two stages to a suspension of subpigmentary titanium dioxide.
    Type: Grant
    Filed: November 3, 1994
    Date of Patent: September 19, 1995
    Assignee: Kronos Inc.
    Inventors: Lothar Elfenthal, Rolf Schwindt, Manfred Kluwig