Granted Patent
Utility
US 5,228,808 · App. 07/800,630
Method for preventing the adverse effects of swell in sulfate bearing, expansive clay soils
Inventors:
J. T. McKennon, Norman L. Hains, David C. Hoffman
Patented Case
View Patent ↗
Granted: Jul 20, 1993
Filed: Nov 27, 1991
Inventors
J. T. McKennon
Norman L. Hains
David C. Hoffman
Assignee (at issue)
Chemical Lime 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.