Granted Patent
Utility
US 4,196,559 · App. 05/963,120
Swellable fabrics for ceiling structures
Inventor:
Sven O. B. Ljungbo
Patented Case
View Patent ↗
Granted: Apr 8, 1980
Filed: Nov 22, 1978
Inventor
Sven O. B. Ljungbo
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.