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US4465820A
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Copolyestercarbonates
Assignee: General Electric Co
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Filing: 1983-06-03
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Granted: 1984-08-14
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Expires: 2003-06-03
Abstract
Abstract A new aromatic copolyestercarbonate is achieved with 70 to 95 weight percent ester content and having consistently high 3.2 mm impact strength while maintaining a high level of stress cracking resistance.
Inventors
- 👤 Kenneth F. Miller
- 👤 William Hilakos
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 07:16
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/64
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
91 words
A composition comprising a copolyestercarbonate prepared from a dihydric phenol, a carbonate precursor, a terephthalic acid or ester forming derivative thereof, an isophthalic acid or ester forming derivative thereof, said copolyestercarbonate having (1) from about 70 to about 95 weight percent ester content and (2) a range of terephthalate groups which maintains a consistently high 3.2 millimeter Notched Izod impact resistance for the said copolyestercarbonate while concurrently achieving a high level improvement in stress cracking resistance the terephthalate groups being from about two to about 15 percent of the ester content.
Claim 2
Dependent Claim
91 words
A composition comprising a copolyestercarbonate prepared from a dihydric phenol, a carbonate precursor, a terephthalic acid or ester forming derivative thereof, an isophthalic acid or ester forming derivative thereof, said copolyestercarbonate having (1) from about 70 to about 95 weight percent ester content and (2) a range of terephthalate groups which maintains a consistently high 3.2 millimeter Notched Izod impact resistance for the said copolyestercarbonate while concurrently achieving a high level improvement in stress cracking resistance the terephthalate groups being from about two to about 15 percent of the ester content.
Claim 3
Dependent Claim
19 words
A composition in accordance with claim 1 wherein the ester content is from five to about ten percent terephthalate.
Claim 4
Dependent Claim
14 words
A composition in accordance with claim 1 wherein the dihydric phenol is bisphenol A.
Claim 5
Dependent Claim
14 words
A composition in accordance with claim 2 wherein the dihydric phenol is bisphenol A.
Claim 6
Dependent Claim
20 words
A composition in accordance with claim 1 wherein the weight percent ester content is from about 75 to about 90.
Claim 7
Dependent Claim
10 words
An article injection molded from a composition of claim 1.
Claim 8
Dependent Claim
10 words
An article injection molded from a composition of claim 4.
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) | 1987-08-14 | 1988-02-13 | 1988-08-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-08-14 | 1992-02-13 | 1992-08-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-08-14 | 1996-02-13 | 1996-08-14 | $7700.00 | Window Closed / Lapsed |