US4169933A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquid crystal copolyesters containing terephthalic acid and 2,6-naphthalenedicarboxylic acid
Assignee: Eastman Chemical Co
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Filing: 1977-08-08
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Granted: 1979-10-02
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Expires: 1997-08-08
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 p-acyloxybenzoic acid 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
2026-10-24 12:41
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/02; C08G63/60; C08G63/605
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
71 words
A copolyester having a fiber forming molecular weight consisting essentially of the following divalent radicals: ##STR10## wherein R 1 is ##STR11## and the range of ##STR12## is from 10 to about 60 mole percent, based on the total moles of ##STR13## combined, and the range of radical (C) is from about 8 to about 70 mole percent, based on the total moles of radical (A), radical (B) and radical (C) combined.
Claim 2
Dependent Claim
71 words
A copolyester having a fiber forming molecular weight consisting essentially of the following divalent radicals: ##STR10## wherein R 1 is ##STR11## and the range of ##STR12## is from 10 to about 60 mole percent, based on the total moles of ##STR13## combined, and the range of radical (C) is from about 8 to about 70 mole percent, based on the total moles of radical (A), radical (B) and radical (C) combined.
Claim 3
Dependent Claim
18 words
The copolyester of claim 1 wherein the range of radical (C) is from 15 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) | 1982-10-01 | 1983-04-02 | 1983-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-10-01 | 1987-04-02 | 1987-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-10-01 | 1991-04-02 | 1991-10-02 | $7700.00 | Window Closed / Lapsed |