Granted Patent
Utility
US 5,719,216 · App. 08/752,987
Preparation process for polymer-modified bitumen
Inventors:
Wilhelmina Elisabeth Maria Schermer, Koen Steernberg
Patented Case
View Patent ↗
Granted: Feb 17, 1998
Filed: Nov 21, 1996
Inventors
Wilhelmina Elisabeth Maria Schermer
Koen Steernberg
Assignee (at issue)
SHELL OIL COMPANY
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.