Granted Patent
Utility
US 4,838,895 · App. 07/179,350
Process for the preparation of concentrated aqueous dye formulations by desalination and concentration by membrane separation in presence of sodium salt
Inventors:
Roberto Galli, Petr Kvita
Patented Case
View Patent ↗
Granted: Jun 13, 1989
Filed: Apr 8, 1988
Inventors
Roberto Galli
Petr Kvita
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.