IP Library › Granted Patent US 5,071,993
Granted Patent Utility
US 5,071,993 · App. 07/405,916

Bis(dibenzoxazoyl)thiophene fluorescent brighteners

Inventors: David G. Leppard, Eric Vieira
Patented Case View Patent ↗
Granted: Dec 10, 1991 Filed: Sep 12, 1989
Inventors
David G. Leppard
Eric Vieira
Assignee (at issue)
Ciba-Geigy

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Quick Facts
Patent No.
US 5,071,993
App. No.
07/405,916
Filed
1989-09-12
Granted
1991-12-10
Kind
A