US4657955A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flameproofing agents, their preparation and their use for flameproofing polycarbonates
Assignee: Bayer AG
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Filing: 1986-06-11
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Granted: 1987-04-14
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Expires: 2006-06-11
Abstract
Abstract The present invention relates to new phthalimides of the formula (I) ##STR1## wherein n is an integer of from 1 to 12, preferably 1 to 4 and especially 1 to 2 and R is H or F, and their preparation, these phthalimides being suitable, in combination with alkali metal salts, as flameproofing agent combinations for thermoplastic, branched, aromatic polycarbonates.
Inventors
- 👤 Hans-Jurgen Kress
- 👤 Klaus Kircher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 09:10
CPC Classifications
C; C07; C07D; C07D209/00; C07D209/02; C07D209/44; C07D209/48; C08; C08K; C08K5/00; C08K5/16; C08K5/34; C08K5/3412; C08K5/3415; C08K5/3417
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
71 words
A process for flameproofing thermoplastic, branched, aromatic polycarbonates made from halogen-free, phenolic components, comprising incorporating therein about 0.1 to 1% by weight, based on the polycarbonate, of a phthalimide of the formula ##STR6## wherein n is an integer from 1 to 12 and R is hydrogen or a fluorine atom and 0.02 to 2% by weight based on the polycarbonate of an alkali metal salt of an organic or inorganic acid.
Claim 2
Dependent Claim
71 words
A process for flameproofing thermoplastic, branched, aromatic polycarbonates made from halogen-free, phenolic components, comprising incorporating therein about 0.1 to 1% by weight, based on the polycarbonate, of a phthalimide of the formula ##STR6## wherein n is an integer from 1 to 12 and R is hydrogen or a fluorine atom and 0.02 to 2% by weight based on the polycarbonate of an alkali metal salt of an organic or inorganic acid.
Claim 3
Dependent Claim
52 words
A process according to claim 1 wherein the phthalimide and the metal salt are incorporated individually or as a mixture, by mixing and subsequent granulation via a twin-screw extruder at a composition temperature of 280°-310° C., and a throughput of 5 kg/hour is achieved at a speed of rotation of 80-100 revolutions/minute.
Claim 4
Dependent Claim
13 words
A process according to claim 2 wherein the composition temperature is 290°-300° C.
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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) | 1990-04-13 | 1990-10-13 | 1991-04-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-04-13 | 1994-10-13 | 1995-04-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-04-13 | 1998-10-13 | 1999-04-14 | $7700.00 | Window Closed / Lapsed |