Granted Patent
Utility
US 4,588,448 · App. 06/669,818
Process for sealing anodically oxidized aluminium or aluminium alloy surfaces
Inventors:
Hans-Peter Baumann, Carl T. Speiser, Ernst Weisskopf
Patented Case
View Patent ↗
Granted: May 13, 1986
Filed: Nov 8, 1984
Inventors
Hans-Peter Baumann
Carl T. Speiser
Ernst Weisskopf
Assignee (at issue)
Sandoz 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.