US4377681A
Expired / Lapsed
US
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Liquid crystal copolyesters
Assignee: Solutia Inc
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Filing: 1982-03-04
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Granted: 1983-03-22
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Expires: 2002-03-04
Abstract
Abstract Disclosed are liquid crystal copolyesters prepared from p-hydroxybenzoic acid, isophthalic acid, hydroquinone and 2,2-bis(4-hydroxyphenyl) propane.
Inventors
- 👤 Oliver D. Deex
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 20:05
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/02; C08G63/60; C08G63/605; C08F; C08F8/00
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
115 words
A copolyester capable of forming a thermotropic melt phase at a temperature below about 340° C. and having a glass transition temperature of at least about 160° C. and an inherent viscosity determined at 30° C. with a solution of 0.5 gram of copolyester per 100 ml of a solvent composed of 60 parts by weight of phenol and 40 parts by weight of tetrachloroethane of at least about 0.3, consisting essentially of the following divalent radicals: ##STR2## wherein the range of radical A is from 10 to 40 mol percent of the copolyester and the range of radical C is from 82 to 95 mole percent, of the total of radicals C and D.
Claim 2
Dependent Claim
115 words
A copolyester capable of forming a thermotropic melt phase at a temperature below about 340° C. and having a glass transition temperature of at least about 160° C. and an inherent viscosity determined at 30° C. with a solution of 0.5 gram of copolyester per 100 ml of a solvent composed of 60 parts by weight of phenol and 40 parts by weight of tetrachloroethane of at least about 0.3, consisting essentially of the following divalent radicals: ##STR2## wherein the range of radical A is from 10 to 40 mol percent of the copolyester and the range of radical C is from 82 to 95 mole percent, of the total of radicals C and D.
Claim 3
Dependent Claim
21 words
The copolyester of claim 1 wherein the range of radical A is from 20 to 35 mole percent of the copolyester.
Claim 4
Dependent Claim
25 words
The copolyester of claim 2 wherein the range of radical C is 88 to 95 mole percent of the total of radicals C and D.
Claim 5
Dependent Claim
15 words
The copolyester of claim 2 or 3, wherein the inherent viscosity is at least 0.5.
References Cited (Backward Citations)
US3637595A
Cited
US3884876A
Cited
US4064108A
Cited
US4075173A
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US4083829A
Cited
US4267304A
Cited
US4299756A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-03-21 | 1986-09-20 | 1987-03-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-03-21 | 1990-09-20 | 1991-03-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-03-21 | 1994-09-20 | 1995-03-22 | $7700.00 | Window Closed / Lapsed |