IP Library › Granted Patent US 4,487,807
Granted Patent Utility
US 4,487,807 · App. 06/427,380

Mixed acid stain inhibitor

Inventors: Paul F. Duffer, Joseph D. Kelly, Helmut Franz
Patented Case View Patent ↗
Granted: Dec 11, 1984 Filed: Sep 29, 1982
Inventors
Paul F. Duffer
Joseph D. Kelly
Helmut Franz
Assignee (at issue)
PPG Industries, Inc.

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Quick Facts
Patent No.
US 4,487,807
App. No.
06/427,380
Filed
1982-09-29
Granted
1984-12-11
Kind
A