US3251807A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the production of polycarbonate resins
Assignee: Honeywell International Inc
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Filing: 1961-04-25
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Granted: 1966-05-17
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Expires: 1981-04-25
Abstract
No abstract record available.
Inventors
- 👤 Rudolph D Deanin
- 👤 Ann V Pinter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:51
CPC Classifications
C; C08; C08G; C08G64/00; C08G64/20; C08G64/22; C08G64/24; C08G64/04; C08G64/06; C08G64/14
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
126 words
A PORCESS FOR THE PREPARATION OF A METHANOL-POLYCARBONATE RESIN WHICH COMPRISES: (I) REACTING TOGETHER PHOSGENE AND 2,2-(4,4''-DIHYDROXY-DIPHENYL)-PROPANE IN A MOLECULAR RATIO OF FROM ABOUT 1.1 TO 1.5:1 IN AN AQUEOUS ALKALINE MEDIUM IN THE PRESENCE OF AN INERT SOLVENT WHICH IS IMMISCIBLE IN WATER AND IN THE PRESENCE OF A CATALYTIC AMOUNT OF A QUARTERNARY AMMONIUM COMPOUND AS A CATALYST; (II) RECOVERING THE RESULTANT POLYCARBONATE RESIN FROM THE REACTION MIXTURE OF (I); (III) REACTING SAID POLYCARBONATE WITH AT LEAST ABOUT 75%, BY WEIGHT, BASED ON THE WEIGHT OF SAID POLYCARBONATE RESIN, OF METHANOL AT A TEMPERATURE OF FROM ABOUT 25*C. TO THE BOILING POINT OF SAID METHANOL FOR AT LEAST ABOUT ONE HOUR; AND (IV) RECOVERING THE RESULTANT METHANOL-POLYCARBONATE RESIN FROM THE REACTION MIXTURE OF (III).
Claim 2
Dependent Claim
126 words
A PORCESS FOR THE PREPARATION OF A METHANOL-POLYCARBONATE RESIN WHICH COMPRISES: (I) REACTING TOGETHER PHOSGENE AND 2,2-(4,4''-DIHYDROXY-DIPHENYL)-PROPANE IN A MOLECULAR RATIO OF FROM ABOUT 1.1 TO 1.5:1 IN AN AQUEOUS ALKALINE MEDIUM IN THE PRESENCE OF AN INERT SOLVENT WHICH IS IMMISCIBLE IN WATER AND IN THE PRESENCE OF A CATALYTIC AMOUNT OF A QUARTERNARY AMMONIUM COMPOUND AS A CATALYST; (II) RECOVERING THE RESULTANT POLYCARBONATE RESIN FROM THE REACTION MIXTURE OF (I); (III) REACTING SAID POLYCARBONATE WITH AT LEAST ABOUT 75%, BY WEIGHT, BASED ON THE WEIGHT OF SAID POLYCARBONATE RESIN, OF METHANOL AT A TEMPERATURE OF FROM ABOUT 25*C. TO THE BOILING POINT OF SAID METHANOL FOR AT LEAST ABOUT ONE HOUR; AND (IV) RECOVERING THE RESULTANT METHANOL-POLYCARBONATE RESIN FROM THE REACTION MIXTURE OF (III).
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) | 1969-05-16 | 1969-11-15 | 1970-05-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-05-16 | 1973-11-15 | 1974-05-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-05-16 | 1977-11-15 | 1978-05-17 | $7700.00 | Window Closed / Lapsed |