Granted Patent
Utility
US 5,714,255 · App. 08/680,117
Phosphorescent directional signals and manufacturing method
Inventor:
Ling Yeh
Patented Case
View Patent ↗
Granted: Feb 3, 1998
Filed: Jul 15, 1996
Inventor
Ling Yeh
Assignee (at issue)
BASF SE
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.