US4201856A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquid crystal copolyesters containing terephthalic acid, 2,6-naphthalenedicarboxylic acid, hydroquinone and resorcinol
Assignee: Eastman Chemical Co
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Filing: 1978-05-08
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Granted: 1980-05-06
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Expires: 1998-05-08
Abstract
Abstract Disclosed are liquid crystal copolyesters having melting points low enough to allow the copolyesters to be melt-processed in conventional equipment. The copolyesters are prepared from terephthalic acid, 2,6-naphthalenedicarboxylic acid, a diacyl ester of hydroquinone and a diacyl ester of resorcinol and contain the following divalent radicals: ##STR1##
Inventors
- 👤 Winston J. Jackson, Jr.
- 👤 John C. Morris
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 11:02
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/02; C08G63/12; C08G63/16; C08G63/18; C08G63/19
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
55 words
A copolyester having a fiber-forming molecular weight consisting essentially of the following divalent radicals: ##STR3## wherein the range of ##STR4## is from 20 to 50 mole percent, based on the total moles of ##STR5## combined, and the range of ##STR6## is from 20 to 50 mole percent, based on the total moles of ##STR7## combined.
Claim 2
Dependent Claim
55 words
A copolyester having a fiber-forming molecular weight consisting essentially of the following divalent radicals: ##STR3## wherein the range of ##STR4## is from 20 to 50 mole percent, based on the total moles of ##STR5## combined, and the range of ##STR6## is from 20 to 50 mole percent, based on the total moles of ##STR7## combined.
Claim 3
Dependent Claim
29 words
The polyester of claim 1 wherein the range of ##STR8## is from 30 to 45 mole percent and the range of ##STR9## is from 30 to 50 mole percent.
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) | 1983-05-06 | 1983-11-05 | 1984-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-05-06 | 1987-11-05 | 1988-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-05-06 | 1991-11-05 | 1992-05-06 | $7700.00 | Window Closed / Lapsed |