Granted Patent
Utility
US 6,172,151 · App. 08/927,911
Nonaqueous drag reducing suspensions
Inventors:
Ray L. Johnston, Yung N. Lee
Patented Case
View Patent ↗
Granted: Jan 9, 2001
Filed: Sep 11, 1997
Inventors
Ray L. Johnston
Yung N. Lee
Assignee (at issue)
Conoco Inc.
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.