Granted Patent
Utility
US 5,697,444 · App. 08/806,348
Carboxyalkyl substituted polygalactomannan fracturing fluids
Inventors:
Ralph Moorhouse, Ian W. Cottrell
Patented Case
View Patent ↗
Granted: Dec 16, 1997
Filed: Feb 26, 1997
Inventors
Ralph Moorhouse
Ian W. Cottrell
Assignee (at issue)
Rhone-Poulenc, 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.