Patent US3376261A successfully refreshed from Google Patents.
US3376261A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing polycarbonates
Assignee: Eastman Kodak Co
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Filing: 1966-03-16
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Granted: 1968-04-02
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Expires: 1986-03-16
Abstract
No abstract record available.
Inventors
- 👤 Jr Winston J Jackson
- 👤 John R Caldwell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:05
CPC Classifications
C; C08; C08G; C08G64/00; C08G64/20; C08G64/22; C08G64/24
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
140 words
IN THE PROCESS FOR PREPARING A POLYCARBONATE BY CONDENSATION OF A BISPHENOL WITH A DIACID CHLORIDE WHEREIN TWO LIQUIDS PHASES OF A REACTION MIXTURE COMPRISING (1) AN ALKALINE AQUEOUS PHASE CONTAINING A BISPENOL AND (2) A WATER-IMMISCIBLE ORGANIC SOLVENT PHASE CONTAINING A DIACID CHOLORIDE, ARE INTIMATELY CONTACTED AND AN INTERFACIAL POLYCONDENSATION REACTION PROCEEDS, THE IMPROVEMENT CONSISTING OF HAVING IN THE REACTION MIXTURE (A) FROM 0.1 TO 5.0 WEIGHT PERCENT, BASED ON THE BISPHENOL WEIGHT, OF A SURFACE-ACTIVE AGENT, (B) AN AMOUNT MEASURED IN MILLILITERS OF SAID SOLVENT WHICH IS ABOUT 0.3 TO ABOUT 2.0 TIMES THE WEIGHT OF SAID BISPHENOL MEASURED IN GRAMS, AND (C) FROM ABOUT 1 TO ABOUT 4 VOLUMES PER VOLUME OF SAID ORGANIC SOLVENT OF AN INERT WATER-IMMISCIBLE HYDROCARBON LIQUID NON-SOLVENT FOR THE POLYMER, WHEREBY THE POLYMER FORMS AS A PRECIPITATED SOLID AS THE REACTION PROCEEDS.
Claim 2
Dependent Claim
140 words
IN THE PROCESS FOR PREPARING A POLYCARBONATE BY CONDENSATION OF A BISPHENOL WITH A DIACID CHLORIDE WHEREIN TWO LIQUIDS PHASES OF A REACTION MIXTURE COMPRISING (1) AN ALKALINE AQUEOUS PHASE CONTAINING A BISPENOL AND (2) A WATER-IMMISCIBLE ORGANIC SOLVENT PHASE CONTAINING A DIACID CHOLORIDE, ARE INTIMATELY CONTACTED AND AN INTERFACIAL POLYCONDENSATION REACTION PROCEEDS, THE IMPROVEMENT CONSISTING OF HAVING IN THE REACTION MIXTURE (A) FROM 0.1 TO 5.0 WEIGHT PERCENT, BASED ON THE BISPHENOL WEIGHT, OF A SURFACE-ACTIVE AGENT, (B) AN AMOUNT MEASURED IN MILLILITERS OF SAID SOLVENT WHICH IS ABOUT 0.3 TO ABOUT 2.0 TIMES THE WEIGHT OF SAID BISPHENOL MEASURED IN GRAMS, AND (C) FROM ABOUT 1 TO ABOUT 4 VOLUMES PER VOLUME OF SAID ORGANIC SOLVENT OF AN INERT WATER-IMMISCIBLE HYDROCARBON LIQUID NON-SOLVENT FOR THE POLYMER, WHEREBY THE POLYMER FORMS AS A PRECIPITATED SOLID AS THE REACTION PROCEEDS.
References Cited (Backward Citations)
US2964797A
Cited
US3240755A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-04-02 | 1971-10-02 | 1972-04-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-04-02 | 1975-10-02 | 1976-04-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-04-02 | 1979-10-02 | 1980-04-02 | $7700.00 | Window Closed / Lapsed |