Patent US3803201A successfully refreshed from Google Patents.
US3803201A
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Synthesis of dimethyl carbonate
Assignee: Dow Chemical Co
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Filing: 1971-02-22
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Granted: 1974-04-09
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Expires: 1991-02-22
Abstract
Abstract DIMETHYL CARBONATE IS MADE BY THE REACTION OF METHANOL WITH CYCLIC ETHYLENE OR 1,2-PROPYLENE CARBONATE WHEREIN THE DESCRIBE PRODUCT REMOVED AS PRODUCED BY DISTILLATION OF THE METHANOL-DIMETHYL CARBONATE AZEOTROPE AND IS THEN SEPARATED FROM THE AZEOTROPE BY LOW TEMPERATURE CRYSTALLIZATION AND DISTILLATION.
Inventors
- 👤 J Gilpin
- 👤 A Emmons
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:34
CPC Classifications
C; C07; C07C; C07C68/00; C07C68/08; C07C68/06; C07C68/065
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-04-08 | 1977-10-08 | 1978-04-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-08 | 1981-10-08 | 1982-04-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-08 | 1985-10-08 | 1986-04-09 | $7700.00 | Window Closed / Lapsed |