US4238600A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Copolyesters derived from terephthalic acid, phenylhydroquinone and t-butylhydroquinone
Assignee: Eastman Chemical Co
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Filing: 1979-11-19
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Granted: 1980-12-09
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Expires: 1999-11-19
Abstract
Abstract Copolyesters of terephthalic acid, phenylhydroquinone and 25 to 65 mole percent t-butylhydroquinone based on total moles of diol. These copolyesters are characterized by high melting points, good melt processability, high heat resistance and high oxidative stability. The copolyesters are useful for the manufacture of melt-spun fibers, extruded films and injection molded articles.
Inventors
- 👤 Winston J. Jackson, Jr.
- 👤 Herbert F. Kuhfuss
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 08:54
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/02; C08G63/12; C08G63/16; C08G63/18; C08G63/19
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
36 words
Copolyester having a film- and fiber-forming molecular weight and consisting essentially of the following divalent radicals ##STR2## wherein (C) is present in the amount of about 25 to 65 mole percent based on (B) and (C).
Claim 2
Dependent Claim
36 words
Copolyester having a film- and fiber-forming molecular weight and consisting essentially of the following divalent radicals ##STR2## wherein (C) is present in the amount of about 25 to 65 mole percent based on (B) and (C).
Claim 3
Dependent Claim
18 words
Copolyester of claim 1, wherein (C) is present in the amount of about 30 to 50 mole percent.
Claim 4
Dependent Claim
8 words
Shaped article of the copolyester of claim 1.
Claim 5
Dependent Claim
8 words
Shaped article of the copolyester of claim 2.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-12-09 | 1984-06-09 | 1984-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-12-09 | 1988-06-09 | 1988-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-12-09 | 1992-06-09 | 1992-12-09 | $7700.00 | Window Closed / Lapsed |