US3332964A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tetraalkyl esters of diphenyl methane 3, 4, 3', 4'-tetracarboxylic acid, diphenyl methane 3, 4, 3', 4'-tetracarboxylic acid and the anhydride of said acids
Assignee: Gulf Research and Development Co
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Filing: 1963-06-18
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Granted: 1967-07-25
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Expires: 1983-06-18
Abstract
No abstract record available.
Inventors
- 👤 John H Mccracken
- 👤 Johann G D Schulz
- 👤 Arthur C Whitaker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 17:24
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/16; C07C51/27; C07C51/275
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
66 words
A PROCESS FOR PREPARING A TETRAALKYL ESTER OF DIPHENYL METHANE 3,4,3'',4''-TETRACARBOXYLIC ACID WHICH COMPRISES HYDROGENATING A TETRAALKYL ESTER OF BENZOPHENONE 3,4,3'',4''-TETRACARBOXYLIC ACID WHEREIN THE ALKYL PORTION THEREOF HAS FROM ONE TO 19 CARBON ATOMS IN LIQUID HYDROCARBON IN THE PRESENT OF HYDROGEN AND A HYDROGENATION CATALYST SELECTED FROM THE GROUP CONSISTING OF NICKEL, COBALT AND COPPER CHROMITE AT A TEMPERATURE OF ABOUT 110* TO ABOUT 200*C.
Claim 2
Dependent Claim
66 words
A PROCESS FOR PREPARING A TETRAALKYL ESTER OF DIPHENYL METHANE 3,4,3'',4''-TETRACARBOXYLIC ACID WHICH COMPRISES HYDROGENATING A TETRAALKYL ESTER OF BENZOPHENONE 3,4,3'',4''-TETRACARBOXYLIC ACID WHEREIN THE ALKYL PORTION THEREOF HAS FROM ONE TO 19 CARBON ATOMS IN LIQUID HYDROCARBON IN THE PRESENT OF HYDROGEN AND A HYDROGENATION CATALYST SELECTED FROM THE GROUP CONSISTING OF NICKEL, COBALT AND COPPER CHROMITE AT A TEMPERATURE OF ABOUT 110* TO ABOUT 200*C.
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) | 1970-07-24 | 1971-01-23 | 1971-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-07-24 | 1975-01-23 | 1975-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-07-24 | 1979-01-23 | 1979-07-25 | $7700.00 | Window Closed / Lapsed |