Granted Patent
Utility
US 5,637,262 · App. 08/454,784
Photochromic substituted naphthopyran compounds
Inventors:
Barry Van Gemert, Anil Kumar
Patented Case
View Patent ↗
Granted: Jun 10, 1997
Filed: May 31, 1995
Inventors
Barry Van Gemert
Anil Kumar
Assignee (at issue)
Transitions Optical, Ltd.
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.