US2852492A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Nu, nu'-bis (p-carboalkoxybenzoyl) piperazines and polyesters therefrom
Assignee: Eastman Kodak Co
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Filing: 1956-05-03
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Granted: 1958-09-16
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Expires: 1976-05-03
Abstract
No abstract record available.
Inventors
- 👤 Jack L R Williams
- 👤 Thomas M Laakso
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:03
CPC Classifications
C; C07; C07D; C07D295/00; C07D295/16; C07D295/18; C07D295/182; C07D295/192; C08; C08G; C08G63/00; C08G63/68; C08G63/688; C08G63/6884; C08G63/6886
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
86 words
A CONDENSATION POLYMER HAVING AN INHERENT VISCOSITY OF AT LEAST 0.4 AND BEING THE PRODUCT OBTAINED BY CONDENSING AT 100-300*C. A MIXTURE OF AN ALKYLENE GLYCOL CONTAINING 2-10 CARBON ATOMS WITH NOT MORE THAN AN EQUIMOLAR AMOUNT OF ACIDIC MATERIAL CONSISTING OF 1-20 MOLE PERCENT OF AN N,N''-BIS(P-CARBOALKOXYBENZOYL) PIPERAZINE WHEREIN THE ALKOXY GROUP CONTAINS 1-4 CARBON ATOMS AND 99-80 MOLE PRESENT OF A BIFUNCTIONAL ACIDIC COMPOUND FROM THE GROUP CONSISTING OF AROMATIC DICARBOXYLIC ACIDS AND ALKYL ESTERS THEREOF WHEREIN THE ALKYL GROUP CONTAINS 1-4 CARBON ATOMS.
References Cited (Backward Citations)
US2717896A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-09-15 | 1962-03-17 | 1962-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-09-15 | 1966-03-17 | 1966-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-09-15 | 1970-03-17 | 1970-09-16 | $7700.00 | Window Closed / Lapsed |