Granted Patent
Utility
US 6,545,809 · App. 09/420,717
Color shifting carbon-containing interference pigments
Inventor:
Roger W. Phillips
Patented Case
View Patent ↗
Granted: Apr 8, 2003
Filed: Oct 20, 1999
Inventor
Roger W. Phillips
Assignee (at issue)
Flex Products, 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.