Patent US3290409A successfully refreshed from Google Patents.
US3290409A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of polycarbonate resins
Assignee: General Electric Co
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Filing: 1962-03-08
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Granted: 1966-12-06
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Expires: 1982-03-08
Abstract
No abstract record available.
Inventors
- 👤 Howard E Munro
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:17
CPC Classifications
C; C08; C08G; C08G64/00; C08G64/20; C08G64/22; C08G64/24; C08G64/04; C08G64/06
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
134 words
THE PROCESS FOR PREPARING A CARBONATE POLYMER WHICH PROCESS COMPRISES PASSING A CARBONYL HALIDE THROUGH A SLURRY COMPRISING A SUPENSION OF SOLID PARTICLES IN A SINGLE LIQUID PHASE, THE SUSPENSION OF SOLID PARTICLES COMPRISING (1) A DIHYDRIC PHENOL AND (2) AT LEAST 2 MOLES, PER MOLE OF DIHYDRIC HENOL, OF AT LEAST ONE ACID ACCEPTOR SELECTED FROM THE GROUP CONSISTING OF ALKALI AND ALKALINE EARTH METAL HYDROXIDES, CARBONATES AND BICARBONATES, AND THE SINGLE LIQUID PHASE COMPRISING AN INERT ORGANIC LIQUID WHICH IS A SOLVENT FOR THE CARBONATE POLYMER BUT A NON-SOLVENT FOR THE DIHYDRIC PHENOL AND THE ACID ACCEPTOR, TO FORM A REACTION MIXTURE HAVING A SOLID PHASE, AND A SINGLE LIQUID PHASE COMPRISING A SOLUTION OF THE CARBONATE POLYMER IN SAID INERT ORGANIC LIQUID, AND SEPARATING THE SOLID PHASE FROM THE LIQUID PHASE.
Claim 2
Dependent Claim
134 words
THE PROCESS FOR PREPARING A CARBONATE POLYMER WHICH PROCESS COMPRISES PASSING A CARBONYL HALIDE THROUGH A SLURRY COMPRISING A SUPENSION OF SOLID PARTICLES IN A SINGLE LIQUID PHASE, THE SUSPENSION OF SOLID PARTICLES COMPRISING (1) A DIHYDRIC PHENOL AND (2) AT LEAST 2 MOLES, PER MOLE OF DIHYDRIC HENOL, OF AT LEAST ONE ACID ACCEPTOR SELECTED FROM THE GROUP CONSISTING OF ALKALI AND ALKALINE EARTH METAL HYDROXIDES, CARBONATES AND BICARBONATES, AND THE SINGLE LIQUID PHASE COMPRISING AN INERT ORGANIC LIQUID WHICH IS A SOLVENT FOR THE CARBONATE POLYMER BUT A NON-SOLVENT FOR THE DIHYDRIC PHENOL AND THE ACID ACCEPTOR, TO FORM A REACTION MIXTURE HAVING A SOLID PHASE, AND A SINGLE LIQUID PHASE COMPRISING A SOLUTION OF THE CARBONATE POLYMER IN SAID INERT ORGANIC LIQUID, AND SEPARATING THE SOLID PHASE FROM THE LIQUID PHASE.
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) | 1969-12-05 | 1970-06-06 | 1970-12-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-12-05 | 1974-06-06 | 1974-12-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-12-05 | 1978-06-06 | 1978-12-06 | $7700.00 | Window Closed / Lapsed |