Granted Patent
Utility
US 4,150,994 · App. 05/799,040
Process for the manufacture of photographic silver halide emulsions containing silver halide crystals of the twinned type
Inventor:
Trevor J. Maternaghan
Patented Case
View Patent ↗
Granted: Apr 24, 1979
Filed: May 20, 1977
Inventor
Trevor J. Maternaghan
Assignee (at issue)
Ciba-Geigy
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.