Patent US2739958A successfully refreshed from Google Patents.
US2739958A
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Dyeable nitrogen-containing polyesters
Assignee: Acordis UK Ltd
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Filing: 1953-05-12
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Granted: 1956-03-27
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Expires: 1973-05-12
Abstract
No abstract record available.
Inventors
- 👤 Lincoln James
- 👤 Hammond Kathleen Mary
- 👤 Groombridge Walter Henry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:41
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/68; C08G63/685; C08G63/78; C08G63/82; Y; Y10; Y10S; Y10S8/00; Y10S8/92; Y10S8/922
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
58 words
A PROCESS FOR THE PRODUCTION OF HIGH MELTING CRYSTALLINE AROMATIC POLYESTERS FROM A GLYCOL AND TEREPHTHALIC ACID, WHICH COMPRISES THE STEP OF CARRYING OUT THE CONDENSATION OF THE FREE GLYCOL AND A SIMPLE ESTER OF THE TEREPHTHALIC ACID IN THE PRESENCE OF N:N-DI-(B-HYDROXYETHYL)-ANILINE IN SUFFICIENT PROPORTION TO GIVE A POLYMER HAVING A NITROGEN CONTENT OF 0.25-0.45% BY WEIGHT.
Claim 2
Dependent Claim
58 words
A PROCESS FOR THE PRODUCTION OF HIGH MELTING CRYSTALLINE AROMATIC POLYESTERS FROM A GLYCOL AND TEREPHTHALIC ACID, WHICH COMPRISES THE STEP OF CARRYING OUT THE CONDENSATION OF THE FREE GLYCOL AND A SIMPLE ESTER OF THE TEREPHTHALIC ACID IN THE PRESENCE OF N:N-DI-(B-HYDROXYETHYL)-ANILINE IN SUFFICIENT PROPORTION TO GIVE A POLYMER HAVING A NITROGEN CONTENT OF 0.25-0.45% BY WEIGHT.
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) | 1959-03-27 | 1959-09-26 | 1960-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-03-27 | 1963-09-26 | 1964-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-03-27 | 1967-09-26 | 1968-03-27 | $7700.00 | Window Closed / Lapsed |