Granted Patent
Utility
US 4,292,664 · App. 05/934,408
Dental plaque disclosing light and method
Inventor:
William Mack
Patented Case
View Patent ↗
Granted: Sep 29, 1981
Filed: Aug 17, 1978
Inventor
William Mack
Assignee (at issue)
Clairol Incorporated
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.