Patent US2719853A successfully refreshed from Google Patents.
US2719853A
Expired / Lapsed
US
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Production of dicarboxylic acid anhydrides
Assignee: Atlantic Richfield Co
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Filing: 1951-11-26
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Granted: 1955-10-04
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Expires: 1971-11-26
Abstract
No abstract record available.
Inventors
- 👤 Jr John C Reid
- 👤 George H Bressler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 14:37
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/16; C07C51/21; C07C51/25; C07C51/252
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
38 words
THE METHOD OF PRODUCING DICARBOXYLIC ACID ANHYDRIDES WHICH COMPRISES CONTACTING VAPORIZED CRACKED NAPHTHA CONTAINING SUBSTANTIAL AMOUNTS OF UNSATURATED ALIPHATIC HYDROCARBONS WITH A FREE OXYGEN CONTAINING GAS IN THE PRESENCE OF A HEATED CATALYST CONSISTING ESSENTIALLY OF VANADIUM ARSENATE.
Claim 2
Independent Claim
38 words
THE METHOD OF PRODUCING DICARBOXYLIC ACID ANHYDRIDES WHICH COMPRISES CONTACTING VAPORIZED CRACKED NAPHTHA CONTAINING SUBSTANTIAL AMOUNTS OF UNSATURATED ALIPHATIC HYDROCARBONS WITH A FREE OXYGEN CONTAINING GAS IN THE PRESENCE OF A HEATED CATALYST CONSISTING ESSENTIALLY OF VANADIUM ARSENATE.
References Cited (Backward Citations)
GB291419A
Cited
US1975476A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1958-10-03 | 1959-04-04 | 1959-10-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-10-03 | 1963-04-04 | 1963-10-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-10-03 | 1967-04-04 | 1967-10-04 | $7700.00 | Window Closed / Lapsed |