US2766281A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of phthalic acids
Assignee: Monsanto Chemicals Ltd
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Filing: 1952-11-20
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Granted: 1956-10-09
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Expires: 1972-11-20
Abstract
No abstract record available.
Inventors
- 👤 Ferdinand B Zienty
- 👤 Marshall C Freerks
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:20
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/16; C07C51/27; C07C51/275
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
100 words
IN A PROCESS FOR THE PREPARATIONN OF A PHTHALIC ACID BY THE OXIDATION OF A XYLENE, THE STEPS COMPRISING SLOWLY ADDING NITRIC ACID TO A XYLENE WHILE MAINTAINING A TEMPERATURE FROM ABOUT 120* C. TO APPROXIMATELY THE BOILING POINT OF XYLENE AND WHILE REMOVING WATER BY DISTILLATION THEREBY FORMING A TOLURIC ACID, AND THEN SLOWLY ADDING NITRIC ACID TO THE TOULIC ACID MAINTAINED IN A FLUID STATE AT A TEMPERATURE GREATER THAN ABOUT 140* C. WHILE REMOVING WATER BY DISTILLATION, SAID REACTIONS BEING CARRIED OUT AT ATMOSPHERIC PRESSURE IN AN INERT ORGANIC MEDIUM WHICH IS LIQUID AT THE REACTION TEMPERATURES.
Claim 2
Dependent Claim
100 words
IN A PROCESS FOR THE PREPARATIONN OF A PHTHALIC ACID BY THE OXIDATION OF A XYLENE, THE STEPS COMPRISING SLOWLY ADDING NITRIC ACID TO A XYLENE WHILE MAINTAINING A TEMPERATURE FROM ABOUT 120* C. TO APPROXIMATELY THE BOILING POINT OF XYLENE AND WHILE REMOVING WATER BY DISTILLATION THEREBY FORMING A TOLURIC ACID, AND THEN SLOWLY ADDING NITRIC ACID TO THE TOULIC ACID MAINTAINED IN A FLUID STATE AT A TEMPERATURE GREATER THAN ABOUT 140* C. WHILE REMOVING WATER BY DISTILLATION, SAID REACTIONS BEING CARRIED OUT AT ATMOSPHERIC PRESSURE IN AN INERT ORGANIC MEDIUM WHICH IS LIQUID AT THE REACTION TEMPERATURES.
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) | 1959-10-09 | 1960-04-09 | 1960-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-10-09 | 1964-04-09 | 1964-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-10-09 | 1968-04-09 | 1968-10-09 | $7700.00 | Window Closed / Lapsed |