Patent US4182838A successfully refreshed from Google Patents.
US4182838A
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Polycarbonate compositions having improved flame retardance and improved water vapor transmission
Assignee: General Electric Co
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Filing: 1978-02-28
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Granted: 1980-01-08
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Expires: 1998-02-28
Abstract
Abstract Improved flame retardance and improved water vapor transmission are imparted to high molecular weight aromatic polycarbonate resins by selecting appropriate diphenols and controlling the degree to which these particular diphenols are halogenated.
Inventors
- 👤 Victor Mark
- 👤 Charles V. Hedges
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:51
CPC Classifications
C; C08; C08G; C08G64/00; C08G64/04; C08G64/045; C07; C07C; C07C37/00; C07C37/62
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
80 words
A high molecular weight aromatic polycarbonate having improved flame retardance and improved water vapor transmission, said polycarbonate having an I.V. of about 0.40-1.0 dl/g. and being represented by the general formula ##STR3## wherein Xm and Xn can each independently be a halogen and mixtures thereof; m and n are each 0.0 to about 2.5 with the proviso that m+n equal at least 0.1, but no more than about 2.5 and, Y and Y' can independently be hydrogen and a halogen.
Claim 2
Dependent Claim
80 words
A high molecular weight aromatic polycarbonate having improved flame retardance and improved water vapor transmission, said polycarbonate having an I.V. of about 0.40-1.0 dl/g. and being represented by the general formula ##STR3## wherein Xm and Xn can each independently be a halogen and mixtures thereof; m and n are each 0.0 to about 2.5 with the proviso that m+n equal at least 0.1, but no more than about 2.5 and, Y and Y' can independently be hydrogen and a halogen.
Claim 3
Dependent Claim
12 words
The polycarbonate of claim 1 wherein Xm and Xn are each chlorine.
Claim 4
Dependent Claim
12 words
The polycarbonate of claim 1 wherein Xm and Xn are each bromine.
Claim 5
Dependent Claim
9 words
The polycarbonate of claim 1 wherein m+n equal 1.5.
Claim 6
Dependent Claim
12 words
The polycarbonate of claim 1 wherein Y and Y' are each hydrogen.
Claim 7
Dependent Claim
14 words
The polycarbonate of claim 1 wherein Y and Y' are each chlorine or bromine.
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) | 1983-01-07 | 1983-07-09 | 1984-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-01-07 | 1987-07-09 | 1988-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-01-07 | 1991-07-09 | 1992-01-08 | $7700.00 | Window Closed / Lapsed |