US2928830A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pyrazolo-triazole optical brighteners
Assignee: Hickson and Welch Ltd
•
Filing: 1957-09-13
•
Granted: 1960-03-15
•
Expires: 1977-09-13
Abstract
No abstract record available.
Inventors
- 👤 Dennis A W Adams
- 👤 Sarkar Asim Kumar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:07
CPC Classifications
C; C07; C07D; C07D487/00; C07D487/02; C07D487/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
13 words
A COMPOUND SELECTED FROM THE GROUP CONSISTING OF A COMPOUND HAVING THE FORMULA
Claim 2
Dependent Claim
13 words
A COMPOUND SELECTED FROM THE GROUP CONSISTING OF A COMPOUND HAVING THE FORMULA
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-03-15 | 1963-09-14 | 1964-03-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-03-15 | 1967-09-14 | 1968-03-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-03-15 | 1971-09-14 | 1972-03-15 | $7700.00 | Window Closed / Lapsed |