US4061691A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flame-resistant polycarbonate molding compositions
Assignee: Bayer AG
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Filing: 1975-11-24
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Granted: 1977-12-06
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Expires: 1995-11-24
Abstract
Abstract Molding compositions having an oxygen index of greater than 0.30 based on high molecular weight aromatic polycarbonates containing 0.5-20% of organic fibers.
Inventors
- 👤 Dieter Margotte
- 👤 Hugo Vernaleken
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:30
CPC Classifications
C; C08; C08L; C08L69/00; Y; Y10; Y10S; Y10S260/00; Y10S260/24
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
51 words
A molding composition having an oxygen index of greater than 0.30 according to ASTM D-2863/70 comprising an aromatic polycarbonate having a molecular weight of between about 10,000 and 100,000 containing 0.5 to 20 percent by weight of a saturated, thermoplastic polyester fiber which is stable in a melt of the polycarbonate.
Claim 2
Dependent Claim
51 words
A molding composition having an oxygen index of greater than 0.30 according to ASTM D-2863/70 comprising an aromatic polycarbonate having a molecular weight of between about 10,000 and 100,000 containing 0.5 to 20 percent by weight of a saturated, thermoplastic polyester fiber which is stable in a melt of the polycarbonate.
Claim 3
Dependent Claim
51 words
The molding composition of claim 1 wherein the aromatic polycarbonate has a molecular weight of between about 10,000 and 100,000 and wherein the saturated polyester of the fiber has a molecular weight of greater than about 20,000 and wherein the fiber has a length of between about 500 and 50,000 μ.
Claim 4
Dependent Claim
21 words
The molding composition of claim 1 wherein the aromatic polycarbonate contains from about 1 to 5% by weight of the fiber.
Claim 5
Dependent Claim
16 words
The molding composition of claim 1 wherein said aromatic polycarbonate is derived from an aromatic dihydroxydiarylalkane.
Claim 6
Dependent Claim
22 words
The molding composition of claim 1 wherein said aromatic dihydroxydiarylalkane is selected from the group consisting of bis-(4-hydroxy-phenyl)-propane-2,2; bis-(4-hydroxy-3,5-dichlorophenyl)-propane-2,2; bis-(4-hydroxy-3,5-dibromophenyl)-propane-2,2 and bis-(4-hydroxy-3,5-dimethylphenyl)-propane.
Claim 7
Dependent Claim
25 words
The molding composition of claim 1 wherein the saturated polyester fiber is selected from the group consisting of poly(ethylene terephthalate), poly(butylene terephthalate) and poly(1,4-dimethylenecyclohexane terephthalate).
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) | 1980-12-05 | 1981-06-06 | 1981-12-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-12-05 | 1985-06-06 | 1985-12-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-12-05 | 1989-06-06 | 1989-12-06 | $7700.00 | Window Closed / Lapsed |