Granted Patent
Utility
US 4,432,174 · App. 06/390,946
Self-supporting insulation element
Inventors:
Paul Grether, Kurt Brader, Bruno Keller
Patented Case
View Patent ↗
Granted: Feb 21, 1984
Filed: Jun 22, 1982
Inventors
Paul Grether
Kurt Brader
Bruno Keller
Assignee (at issue)
Sulzer Brothers Limited
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.