Patent US3065243A successfully refreshed from Google Patents.
US3065243A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reduction of dicarboxylic acid esters
Assignee: —
•
Filing: —
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Granted: 1962-11-20
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Expires: 1979-11-20
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 16:08
CPC Classifications
C; C07; C07D; C07D307/00; C07D307/02; C07D307/26; C07D307/30; C07D307/32; C07D307/33; C07D315/00; C07D307/04; C07D307/06; C07D307/08
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
61 words
A PROCESS FOR PRODUCING GAMMA-BUTYROLACTONE WHICH COMPRISES CONTACTING A FEED COMPOUND SELECTED FROM THE GROUP GROUP CONSISTING OF MALEIC ANHYDRIDE, SUCCINIC ANHYDRIDE, AND ESTER OF MALEIC, SUCCINIC AND FUMARIC ACID, IN VAPOR PHASE, WITH HYDROGEN AT A PRESSURE OF LESS THAN 5 ATMOSPHERES AND AT A TEMPERATURE BETWEEN ABOUT 100*C. AND ABOUT 400*C. IN THE PRESENCE OF A COPPER CHROMITE CATALYST.
Claim 2
Dependent Claim
61 words
A PROCESS FOR PRODUCING GAMMA-BUTYROLACTONE WHICH COMPRISES CONTACTING A FEED COMPOUND SELECTED FROM THE GROUP GROUP CONSISTING OF MALEIC ANHYDRIDE, SUCCINIC ANHYDRIDE, AND ESTER OF MALEIC, SUCCINIC AND FUMARIC ACID, IN VAPOR PHASE, WITH HYDROGEN AT A PRESSURE OF LESS THAN 5 ATMOSPHERES AND AT A TEMPERATURE BETWEEN ABOUT 100*C. AND ABOUT 400*C. IN THE PRESENCE OF A COPPER CHROMITE CATALYST.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1965-11-19 | 1966-05-21 | 1966-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-11-19 | 1970-05-21 | 1970-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-11-19 | 1974-05-21 | 1974-11-20 | $7700.00 | Window Closed / Lapsed |