Granted Patent
Utility
US 4,908,040 · App. 07/113,311
Anionic cyclodiylide compounds, their preparation and use in washing agents as shading dyes
Inventors:
Rudolf Naef, Claude Eckhardt
Patented Case
View Patent ↗
Granted: Mar 13, 1990
Filed: Oct 28, 1987
Inventors
Rudolf Naef
Claude Eckhardt
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.