Patent US2857440A successfully refreshed from Google Patents.
US2857440A
Expired / Lapsed
US
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Method for production of orthovinyltoluene
Assignee: Dow Chemical Co
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Filing: 1955-06-02
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Granted: 1958-10-21
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Expires: 1975-06-02
Abstract
No abstract record available.
Inventors
- 👤 James L Amos
- 👤 Frederick J Soderquist
- 👤 Robert H Allen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:37
CPC Classifications
C; C07; C07C; C07C4/00; C07C4/08; C07C4/12
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
84 words
A METHOD WHICH COMPRISES THERMALLY DECOMPOSING AN ORTHO-PROPYLTOLUENE BY PASSING VAPORS THEREOF THROUGH A ZONE WHERE THEY ARE HEATED AT A REACTION TEMPERATURE FOR A TIME SUCH THAT ONLY PART OF THE ORTHO-PROPYLTOULENE IS CONSUMED WITH FORMATION OF A MIXTURE COMPRISING UNCONSUMED ORTHO-PROPYLTOLUENE TOGETHER WITH ORTHO-VINYLTOLUENE AS THE MAJOR REACTION PRODUCT AND INDENE AS A MINOR PRODUCT, WHICH MIXTURE CONTAINS LITTLE TO NONE OF A PROPENYLTOLUENE, THE YIELD OF PROPENYLTOLUENE BEING LESS THAN IS FORMED BY THERMALLY DECOMPOSING META-AND PARAISPROPYLTOLUENES UNDER OTHERWISE SIMILAR CONDITIONS.
Claim 2
Independent Claim
84 words
A METHOD WHICH COMPRISES THERMALLY DECOMPOSING AN ORTHO-PROPYLTOLUENE BY PASSING VAPORS THEREOF THROUGH A ZONE WHERE THEY ARE HEATED AT A REACTION TEMPERATURE FOR A TIME SUCH THAT ONLY PART OF THE ORTHO-PROPYLTOULENE IS CONSUMED WITH FORMATION OF A MIXTURE COMPRISING UNCONSUMED ORTHO-PROPYLTOLUENE TOGETHER WITH ORTHO-VINYLTOLUENE AS THE MAJOR REACTION PRODUCT AND INDENE AS A MINOR PRODUCT, WHICH MIXTURE CONTAINS LITTLE TO NONE OF A PROPENYLTOLUENE, THE YIELD OF PROPENYLTOLUENE BEING LESS THAN IS FORMED BY THERMALLY DECOMPOSING META-AND PARAISPROPYLTOLUENES UNDER OTHERWISE SIMILAR CONDITIONS.
References Cited (Backward Citations)
US1541175A
Cited
US2531327A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-10-20 | 1962-04-21 | 1962-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-10-20 | 1966-04-21 | 1966-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-10-20 | 1970-04-21 | 1970-10-21 | $7700.00 | Window Closed / Lapsed |