US2495229A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of tetrahydroanthraquinones
Assignee: BUFFALO ELECTRO CHEM CO
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Filing: 1947-03-13
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Granted: 1950-01-24
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Expires: 1967-03-13
Abstract
No abstract record available.
Inventors
- 👤 Lynn H Dawsey
- 👤 Robert R Umhoefer
- 👤 Carl K Muehlhausser
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 13:27
CPC Classifications
C; C01; C01B; C01B15/00; C01B15/01; C01B15/022; C01B15/023
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
85 words
IN A PROCESS IN WHICH A SOLUTION CONSISTING OF AN ANTHRAQUINONE COMPOUND AND AN ORGANIC SOLVENT THEREFOR IS SUBJECTED TO THE ACTION OF HYDROGEN IN THE PRESENCE OF A HYDROGENATION CATALYST TO PRODUCE THE CORRESPONDING TETRAHYDROANTHRAHYDROQUINONE DERIVATIVE, SAID ANTRAQUINONE COMPOUND BEING SELECTED FROM THE GROUP CONSISTING OF ANTHRAQUINONE AND ITS 2-LOWER ALKYL SUBSTITUTION PRODUCTS, THE IMPROVEMENT WHICH CONSISTS OF USING A POROUS NICKEL CATALYST UNDER 1 TO 3 ATMOSPHERES HYDROGEN PRESSURE WHILE MAINTAINING THE TEMPERATURE OF THE SOLUTION IN THE RANGE BETWEEN 20* AND 75*C.
Claim 2
Dependent Claim
85 words
IN A PROCESS IN WHICH A SOLUTION CONSISTING OF AN ANTHRAQUINONE COMPOUND AND AN ORGANIC SOLVENT THEREFOR IS SUBJECTED TO THE ACTION OF HYDROGEN IN THE PRESENCE OF A HYDROGENATION CATALYST TO PRODUCE THE CORRESPONDING TETRAHYDROANTHRAHYDROQUINONE DERIVATIVE, SAID ANTRAQUINONE COMPOUND BEING SELECTED FROM THE GROUP CONSISTING OF ANTHRAQUINONE AND ITS 2-LOWER ALKYL SUBSTITUTION PRODUCTS, THE IMPROVEMENT WHICH CONSISTS OF USING A POROUS NICKEL CATALYST UNDER 1 TO 3 ATMOSPHERES HYDROGEN PRESSURE WHILE MAINTAINING THE TEMPERATURE OF THE SOLUTION IN THE RANGE BETWEEN 20* AND 75*C.
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) | 1953-01-23 | 1953-07-25 | 1954-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-01-23 | 1957-07-25 | 1958-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-01-23 | 1961-07-25 | 1962-01-24 | $7700.00 | Window Closed / Lapsed |