Granted Patent
Utility
US 4,267,044 · App. 05/894,845
Thixotropic polyurethane compositions as sealants for membrane separatory devices
Inventors:
Thaddeus F. Kroplinski, Barton C. Case
Patented Case
View Patent ↗
Granted: May 12, 1981
Filed: Apr 10, 1978
Inventors
Thaddeus F. Kroplinski
Barton C. Case
Assignee (at issue)
NL Industries, Inc.
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.