US2999844A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polycarbonate preparation under anhydrous conditions
Assignee: Bayer AG
•
Filing: 1957-10-21
•
Granted: 1961-09-12
•
Expires: 1977-10-21
Abstract
No abstract record available.
Inventors
- 👤 Muller Erwin
- 👤 Bayer Otto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 04:53
CPC Classifications
C; C08; C08G; C08G64/00; C08G64/20; C08G64/26; C08G64/28; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/42; C08G18/44; C08G64/02; C08G64/0208; C08G64/16; C08G64/1608; C08G64/22; C08G64/24
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
24 words
A METHOD FOR MAKING A POLYCARBONATE WHICH COMPRISES REACTING A COMPOUND SELECTED DROM THE GROUP CONSISTING OF PHOSGENE AND AN ORGANIC COMPOUND HAVING TWO
Claim 2
Independent Claim
24 words
A METHOD FOR MAKING A POLYCARBONATE WHICH COMPRISES REACTING A COMPOUND SELECTED DROM THE GROUP CONSISTING OF PHOSGENE AND AN ORGANIC COMPOUND HAVING TWO
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-09-11 | 1965-03-13 | 1965-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-09-11 | 1969-03-13 | 1969-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-09-11 | 1973-03-13 | 1973-09-12 | $7700.00 | Window Closed / Lapsed |