US3220980A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polymerization of aromatic cyclic carbonate monomers
Assignee: General Electric Co
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Filing: 1964-07-01
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Granted: 1965-11-30
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Expires: 1984-07-01
Abstract
No abstract record available.
Inventors
- 👤 Robert J Prochaska
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:54
CPC Classifications
C; C07; C07D; C07D323/00; C07D321/00; C07D321/12; C07D327/00; C07D327/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
62 words
A PROCESS FOR PREPARING AN AROMATIC CARBONATE POLYMER WHICH PROCESS COMPRISES HEATING AN AROMATIC CARBONATE MONOMER IN THE PRESENCE OF A CATALYTIC AMOUNT OF AT LEAST ONE MEMBER SELECTED FROM THE CLASS CONSISTING OF AN ALKALI METAL; A HYDROXIDE, A CARBONATE, AND ALKOXIDE AND AN ARYLOXIDE OF AN ALKALI METAL; AND A QUATERNARY AMMONIUM HYDROXIDE; SAID AROMATIC CARBONATE MONOMER HAVING THE FORMULA
Claim 2
Dependent Claim
62 words
A PROCESS FOR PREPARING AN AROMATIC CARBONATE POLYMER WHICH PROCESS COMPRISES HEATING AN AROMATIC CARBONATE MONOMER IN THE PRESENCE OF A CATALYTIC AMOUNT OF AT LEAST ONE MEMBER SELECTED FROM THE CLASS CONSISTING OF AN ALKALI METAL; A HYDROXIDE, A CARBONATE, AND ALKOXIDE AND AN ARYLOXIDE OF AN ALKALI METAL; AND A QUATERNARY AMMONIUM HYDROXIDE; SAID AROMATIC CARBONATE MONOMER HAVING THE FORMULA
References Cited (Backward Citations)
US3137706A
Cited
US3155683A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-11-29 | 1969-05-31 | 1969-11-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-11-29 | 1973-05-31 | 1973-11-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-11-29 | 1977-05-31 | 1977-11-30 | $7700.00 | Window Closed / Lapsed |