Granted Patent
Utility
US 4,810,573 · App. 07/075,567
Self-healing bentonite sheet material composite article
Inventor:
Todd D. Harriett
Patented Case
View Patent ↗
Granted: Mar 7, 1989
Filed: Jul 20, 1987
Inventor
Todd D. Harriett
Assignee (at issue)
American Colloid 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.