Granted Patent
Utility
US 4,902,478 · App. 07/235,897
Indicator sheet for an autoclave test pack
Inventor:
Roger Hambleton
Patented Case
View Patent ↗
Granted: Feb 20, 1990
Filed: Sep 7, 1988
Inventor
Roger Hambleton
Assignee (at issue)
The Victoria University of Manchester
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.