Granted Patent
Utility
US 4,486,476 · App. 06/597,471
Preparation for making inorganic building materials water-repellent
Inventors:
Herwig Fritsch, Gotz Koerner, Herbert Quilitsch, Eckehard Schamberg
Patented Case
View Patent ↗
Granted: Dec 4, 1984
Filed: Apr 5, 1984
Inventors
Herwig Fritsch
Gotz Koerner
Herbert Quilitsch
Eckehard Schamberg
Assignee (at issue)
Th. Goldschmidt. AG
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.