Patent US2499003A successfully refreshed from Google Patents.
US2499003A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of preparing 1-chloro-2-carboxyanthraquinone
Assignee: Wyeth Holdings LLC
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Filing: 1946-11-02
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Granted: 1950-02-28
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Expires: 1966-11-02
Abstract
No abstract record available.
Inventors
- 👤 Scalera Mario
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 09:35
CPC Classifications
C; C07; C07C; C07C66/00; C07C66/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
45 words
A PROCESS FOR THE PREPARATION OF 1-CHLORO-2CARBOXYANTHRAQUINONE WHICH COMPRISES REACTING 1-NITRO-2-CARBOXYANTHRAQUINONE WITH AN ALKALI METAL SULFITE AT ELEVATED TEMPERATURES IN AQUEOUS SOLUTION TO FORM 1-SULFO-2-CARBOXYANTHRAQUINONE, ACIDIFYING AND REACTING THE ACIDIFIED MIXTURE AT ELEVATED TEMPERATURES WITH THE MIXTURE OF A WATER-SOLUBLE CHLORIDE AND A WATER-SOLUBLE CHLORATE.
Claim 2
Dependent Claim
45 words
A PROCESS FOR THE PREPARATION OF 1-CHLORO-2CARBOXYANTHRAQUINONE WHICH COMPRISES REACTING 1-NITRO-2-CARBOXYANTHRAQUINONE WITH AN ALKALI METAL SULFITE AT ELEVATED TEMPERATURES IN AQUEOUS SOLUTION TO FORM 1-SULFO-2-CARBOXYANTHRAQUINONE, ACIDIFYING AND REACTING THE ACIDIFIED MIXTURE AT ELEVATED TEMPERATURES WITH THE MIXTURE OF A WATER-SOLUBLE CHLORIDE AND A WATER-SOLUBLE CHLORATE.
References Cited (Backward Citations)
US1895100A
Cited
US1965818A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-02-27 | 1953-08-29 | 1954-02-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-02-27 | 1957-08-29 | 1958-02-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-02-27 | 1961-08-29 | 1962-02-28 | $7700.00 | Window Closed / Lapsed |