IP Library › Granted Patent US 4,897,293
Granted Patent Utility
US 4,897,293 · App. 07/217,810

Novel roofing membrane and method of making

Inventor: Charles Thessen
Patented Case View Patent ↗
Granted: Jan 30, 1990 Filed: Jul 12, 1988
Inventor
Charles Thessen
Assignee (at issue)
The Kendall Company LP

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Quick Facts
Patent No.
US 4,897,293
App. No.
07/217,810
Filed
1988-07-12
Granted
1990-01-30
Kind
A