Granted Patent
Utility
US 5,602,804 · App. 08/510,762
Long term rapid color changing time indicator
Inventor:
David J. Haas
Patented Case
View Patent ↗
Granted: Feb 11, 1997
Filed: Aug 3, 1995
Inventor
David J. Haas
Assignee (at issue)
Temtec, 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.