IP Library › Granted Patent US 4,752,448
Granted Patent Utility
US 4,752,448 · App. 06/943,539

Drug abuse test paper

Inventors: Henry J. Wells, Robin L. Binder
Patented Case View Patent ↗
Granted: Jun 21, 1988 Filed: Dec 17, 1986
Inventors
Henry J. Wells
Robin L. Binder
Assignee (at issue)
Keystone Diagnostics, Inc.

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Quick Facts
Patent No.
US 4,752,448
App. No.
06/943,539
Filed
1986-12-17
Granted
1988-06-21
Kind
A