Patent US2821551A successfully refreshed from Google Patents.
US2821551A
Expired / Lapsed
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Process for production of aromatic carboxylic acids
Assignee: Imhausen Werke GmbH
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Filing: 1952-07-29
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Granted: 1958-01-28
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Expires: 1972-07-29
Abstract
No abstract record available.
Inventors
- 👤 Katzschmann Ewald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:32
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/16; C07C51/21; C07C51/255; C07C51/23
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
43 words
THE PROCESS OF PREPARING A HYDROXY METHYL BENZOIC ACID WHICH COMPRISES CONVERTING A TOLYL ALCOHOL INTO AN ESTER AND THEN OXIDIZING THE ESTER IN LIQUID PHASE WITH A GAS CONTAINING ELEMENTAL OXYGEN AT AN ELEVATED TEMPERATURE IN THE PRESENCE OF AN OXIDATION CATALYST.
Claim 2
Dependent Claim
43 words
THE PROCESS OF PREPARING A HYDROXY METHYL BENZOIC ACID WHICH COMPRISES CONVERTING A TOLYL ALCOHOL INTO AN ESTER AND THEN OXIDIZING THE ESTER IN LIQUID PHASE WITH A GAS CONTAINING ELEMENTAL OXYGEN AT AN ELEVATED TEMPERATURE IN THE PRESENCE OF AN OXIDATION CATALYST.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-01-27 | 1961-07-29 | 1962-01-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-01-27 | 1965-07-29 | 1966-01-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-01-27 | 1969-07-29 | 1970-01-28 | $7700.00 | Window Closed / Lapsed |