Patent US858769A successfully refreshed from Google Patents.
Patent US2940985A successfully refreshed from Google Patents.
US2940985A
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US
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Selective hydrogenation of 3, 6-endoxy-3, 6-dihydrophthalic acid esters
Assignee: Olin Corp
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Filing: 1958-03-19
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Granted: 1960-06-14
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Expires: 1978-03-19
Abstract
No abstract record available.
Inventors
- 👤 Cords Helmuth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:10
CPC Classifications
C; C07; C07D; C07D493/00; C07D493/02; C07D493/08; C07C; C07C51/00; C07C51/347; C07C51/36
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
41 words
A PROCESS FOR SELECTIVELY HYDROGENATING A 3,6-ENDOXY3,-DIHYDROPHTHALATE, WHICH COMPRISES REACTING A DIESTER OF 3,6-ENDOXY-3,6-DIHYDROPHTHATIC ACID WITH HYDROGEN IN THE PRESENCE OF SPONGE NICKEL CATALYST AND A SOLVENT SELECTED FROM THE CLASS CONSISTING OF TRICHLOROETHYLENE AND CHLOROBENZENE, AND RECOVERING THE 3,6-ENDOXY-3,4,5,6TETRAHYDROPHTHALATE FORMED.
Claim 2
Dependent Claim
41 words
A PROCESS FOR SELECTIVELY HYDROGENATING A 3,6-ENDOXY3,-DIHYDROPHTHALATE, WHICH COMPRISES REACTING A DIESTER OF 3,6-ENDOXY-3,6-DIHYDROPHTHATIC ACID WITH HYDROGEN IN THE PRESENCE OF SPONGE NICKEL CATALYST AND A SOLVENT SELECTED FROM THE CLASS CONSISTING OF TRICHLOROETHYLENE AND CHLOROBENZENE, AND RECOVERING THE 3,6-ENDOXY-3,4,5,6TETRAHYDROPHTHALATE FORMED.
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) | 1963-06-14 | 1963-12-14 | 1964-06-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-06-14 | 1967-12-14 | 1968-06-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-06-14 | 1971-12-14 | 1972-06-14 | $7700.00 | Window Closed / Lapsed |