Granted Patent
Utility
US 6,541,547 · App. 08/709,975
Process for stabilization of polyolefins in permanent contact with extracting media
Inventors:
Thomas R. Schmutz, Erich Kramer, Hans Zweifel, Bruno Rotzinger
Patented Case
View Patent ↗
Granted: Apr 1, 2003
Filed: Sep 9, 1996
Inventors
Thomas R. Schmutz
Erich Kramer
Hans Zweifel
Bruno Rotzinger
Assignee (at issue)
Ciba Specialty Chemicals Corporation
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.