Granted Patent
Utility
US 4,322,177 · App. 06/054,145
Method and devices for forming highly retro-reflecting roadway surface marking
Inventor:
Ludwig Eigenmann
Patented Case
View Patent ↗
Granted: Mar 30, 1982
Filed: Jul 2, 1979
Inventor
Ludwig Eigenmann
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.