Granted Patent
Utility
US 5,635,458 · App. 08/397,436
Water-based drilling fluids for reduction of water adsorption and hydration of argillaceous rocks
Inventors:
Li-Jein Lee, Arvind D. Patel
Patented Case
View Patent ↗
Granted: Jun 3, 1997
Filed: Mar 1, 1995
Inventors
Li-Jein Lee
Arvind D. Patel
Assignee (at issue)
M-I Drilling Fluids L.L.C.
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.