Granted Patent
Utility
US 4,956,167 · App. 07/327,392
Silicas
Inventors:
Derek Aldcroft, John R. Newton, James P. Quinn, Peter W. Stanier
Patented Case
View Patent ↗
Granted: Sep 11, 1990
Filed: Mar 22, 1989
Inventors
Derek Aldcroft
John R. Newton
James P. Quinn
Peter W. Stanier
Assignee (at issue)
Unilever Patent Holdings B.V.
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.