Granted Patent
Utility
US 6,013,307 · App. 08/159,405
Method of producing forgery-proof colored printed articles
Inventors:
Hanspeter Hauser, Werner Helmut Gerber, Abul Iqbal, Pierre Maurer
Patented Case
View Patent ↗
Granted: Jan 11, 2000
Filed: Nov 30, 1993
Inventors
Hanspeter Hauser
Werner Helmut Gerber
Abul Iqbal
Pierre Maurer
Assignee (at issue)
Ciba Specialty Chemicals Corporation
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.