IP Library › Granted Patent US 4,580,584
Granted Patent Utility
US 4,580,584 · App. 06/581,516

Cigarette filter

Inventors: Martin L. Reynolds, Dorothy M. Frank, Tilford F. Riehl
Patented Case View Patent ↗
Granted: Apr 8, 1986 Filed: Feb 21, 1984
Inventors
Martin L. Reynolds
Dorothy M. Frank
Tilford F. Riehl
Assignee (at issue)
Brown & Williamson Tobacco Corporation

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Quick Facts
Patent No.
US 4,580,584
App. No.
06/581,516
Filed
1984-02-21
Granted
1986-04-08
Kind
A