Patent US3810901A successfully refreshed from Google Patents.
US3810901A
Expired / Lapsed
US
⏱️ 0.0 years remaining
3-(coumarin-3-ylphenyl)-1,2,4-oxadiazol-5-yl ammonium salts
Assignee: Hickson and Welch Ltd
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Filing: 1972-02-10
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Granted: 1974-05-14
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Expires: 1992-02-10
Abstract
Abstract 3-(COUMARIN - 3 - YLPHENYL)-1,2,5-OXADIAZOL-5-YL AMMONIUM SALTS WHICH MAY HAVE AN AKYL SUBSTITUENT AT THE 7 AND/OR 4 POSITION OF THE COUMARIN RING AND/OR A NONCHROMOPHORIC GROUP (E.G. HALOGEN, ALKYL OR ALKOXY) AT ANOTHER POSITION OF THE COUMARIN RING. THE COMPOUNDS ARE USEFUL IN THE WHITENING, BRIGHTENING AND/OR BLEACHING OF SYNTHETIC AND SEMI-SYNTHETIC FIBERS.
Inventors
- 👤 H Davidson
- 👤 B Leggetter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:42
CPC Classifications
C; C07; C07D; C07D311/00; C07D311/02; C07D311/04; C07D311/06; C07D311/08; C07D311/16
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-05-13 | 1977-11-12 | 1978-05-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-13 | 1981-11-12 | 1982-05-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-13 | 1985-11-12 | 1986-05-14 | $7700.00 | Window Closed / Lapsed |