Granted Patent
Utility
US 4,245,990 · App. 05/971,764
Process for producing solutions of salts of water-soluble carboxylic acids of cationic dyes or optical brighteners
Inventors:
Peter Loew, Walter Lang
Patented Case
View Patent ↗
Granted: Jan 20, 1981
Filed: Dec 21, 1978
Inventors
Peter Loew
Walter Lang
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.