US3131220A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tetrasubstituted polymethylenediamine salts
Assignee: Smith Kline & French Laboratories Ltd
•
Filing: 1958-07-09
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Granted: 1964-04-28
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Expires: 1978-07-09
Abstract
No abstract record available.
Inventors
- 👤 Charles L Zirkle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 17:17
CPC Classifications
C; C07; C07C; C07C215/00; C07C215/02; C07C215/04; C07C215/06; C07C215/08; C07C215/14
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
7 words
A CHEMICAL COMPOUND HAVING THE FOLLOWING FORMULA:
Claim 2
Dependent Claim
7 words
A CHEMICAL COMPOUND HAVING THE FOLLOWING 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) | 1967-04-28 | 1967-10-28 | 1968-04-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-04-28 | 1971-10-28 | 1972-04-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-04-28 | 1975-10-28 | 1976-04-28 | $7700.00 | Window Closed / Lapsed |