IP Library › Granted Patent US 4,421,923
Granted Patent Utility
US 4,421,923 · App. 06/215,680

Ring substituted crown ethers and method of producing same

Inventor: Richard A. Bartsch
Patented Case View Patent ↗
Granted: Dec 20, 1983 Filed: Dec 12, 1980
Inventor
Richard A. Bartsch
Assignee (at issue)
PCR Research Chemicals, Inc.

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Quick Facts
Patent No.
US 4,421,923
App. No.
06/215,680
Filed
1980-12-12
Granted
1983-12-20
Kind
A