US3213060A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polycarbonate purification
Assignee: Eastman Kodak Co
•
Filing: 1961-09-14
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Granted: 1965-10-19
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Expires: 1981-09-14
Abstract
No abstract record available.
Inventors
- 👤 Jr Winston J Jackson
- 👤 Kenneth P Perry
- 👤 John R Caldwell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 07:23
CPC Classifications
C; C08; C08G; C08G64/00; C08G64/40; C08G64/406
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
124 words
A METHOD FOR PURIFYING A BISPHENOL POLYCARBONATE PRODUCT OF AN INTERFACIAL POLYCONDENSATION PROCESS COMPRISING THE STEPS OF (1) SEPARATING SAID POLYCARBONATE PRODUCT AS SOLID PARTICLES FROM SAID POLYCONDENSATION REACTION MIXTURE, (2) AGITATING SAID PARTICLES IN A WASHING MIXTURE COMPRISING WATER AND A CO-ACTIVE PURIFICATION AGENT WHICH IS SELECTED FROM THE GROUP CONSISTING OF ESTER OF MONOCARBOXYLIC ACIDS, KETONES AND ETHERS, SAID COACTIVE AGENT BEING FURTHER CHARACTERIZED IN THAT IT IS (A) WATER-IMMISCIBLE, (B) A SWELLING AGENT FOR SAID PARTICLES, (C) SAID PARTICLES ARE NOT SOLUBLE THEREIN, AND (D) IT IS A SOLVENT FOR SAID BISPHENOL, (3) SEPARATING SAID PARTICLES FROM SAID WASHING MIXTURE WHEREBY SAID PURIFIED POLYCARBONATE PRODUCT IS CHARACTERIZED IN THAT IT CAN BE DISSOLVED IN METHYLENE CHLORIDE TO FORM A CLEAR DOPE.
Claim 2
Independent Claim
124 words
A METHOD FOR PURIFYING A BISPHENOL POLYCARBONATE PRODUCT OF AN INTERFACIAL POLYCONDENSATION PROCESS COMPRISING THE STEPS OF (1) SEPARATING SAID POLYCARBONATE PRODUCT AS SOLID PARTICLES FROM SAID POLYCONDENSATION REACTION MIXTURE, (2) AGITATING SAID PARTICLES IN A WASHING MIXTURE COMPRISING WATER AND A CO-ACTIVE PURIFICATION AGENT WHICH IS SELECTED FROM THE GROUP CONSISTING OF ESTER OF MONOCARBOXYLIC ACIDS, KETONES AND ETHERS, SAID COACTIVE AGENT BEING FURTHER CHARACTERIZED IN THAT IT IS (A) WATER-IMMISCIBLE, (B) A SWELLING AGENT FOR SAID PARTICLES, (C) SAID PARTICLES ARE NOT SOLUBLE THEREIN, AND (D) IT IS A SOLVENT FOR SAID BISPHENOL, (3) SEPARATING SAID PARTICLES FROM SAID WASHING MIXTURE WHEREBY SAID PURIFIED POLYCARBONATE PRODUCT IS CHARACTERIZED IN THAT IT CAN BE DISSOLVED IN METHYLENE CHLORIDE TO FORM A CLEAR DOPE.
References Cited (Backward Citations)
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US3028365A
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US3023101A
Cited
US3046255A
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US3030335A
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US3038879A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-10-18 | 1969-04-19 | 1969-10-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-10-18 | 1973-04-19 | 1973-10-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-10-18 | 1977-04-19 | 1977-10-19 | $7700.00 | Window Closed / Lapsed |