Patent US2820053A successfully refreshed from Google Patents.
US2820053A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Terephthalamates
Assignee: California Research LLC
•
Filing: 1954-06-28
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Granted: 1958-01-14
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Expires: 1974-06-28
Abstract
No abstract record available.
Inventors
- 👤 Bruce W Hotten
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:39
CPC Classifications
C; C07; C07D; C07D221/00; C07D221/02; C07D221/22; C07D221/24
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
5 words
COMPOUNDS HAVING THE GENERAL FORMULA
Claim 2
Dependent Claim
5 words
COMPOUNDS HAVING THE GENERAL 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) | 1961-01-13 | 1961-07-15 | 1962-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-01-13 | 1965-07-15 | 1966-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-01-13 | 1969-07-15 | 1970-01-14 | $7700.00 | Window Closed / Lapsed |