Patent US2539472A successfully refreshed from Google Patents.
US2539472A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the purification of certain water-soluble hydroxycarboxylic acids
Assignee: Individual
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Filing: 1949-07-15
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Granted: 1951-01-30
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Expires: 1969-07-15
Abstract
No abstract record available.
Inventors
- 👤 William P Ratchford
- 👤 Charles H Fisher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 20:17
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/42
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
127 words
A PROCESS COMPRISING REACTING A HYDROXYCARBOXYLIC ACID CONTAINED IN AQUEOUS SOLUTION WITH AN ORGANIC AMINE SELECTED FROM THE GROUP CONSISTING OF A SECONDARY AND TERTIARY ALKYL AMINE CONTAINING FROM 5 TO 12 CARBON ATOMS IN EACH ALKYL GROUP TO FORM AN ORGANIC SOLVENT SOLUBLE SALT OF SAID HYDROXYCARBOXYLIC ACID AND THE AMINE, SAID REACTION BEING CONDUCTED IN THE PRESENCE OF AN ORGANIC, WATER IMMISCIBLE SOLVENT ADAPTED TO DISSOLVE SAID SALT OF SAID AMINE AND HYDROXYCARBOXYLIC ACID AND SELECTED FROM THE GROUP CONSISTING OF AN ALCOHOL CONTAINING AT LEAST FOUR CARBON ATOMS AND CHLOROFORM, SEPARATING THE RESULTING SOLUTION OF THE FORMED SALT OF THE AMINE AND HYDROXYCARBOXYLIC ACID IN THE ORGANIC WATER IMMISCIBLE SOLVENT, DECOMPOSING SAID SALT TO LIBERATE THE FREE HYDROXYCARBOXYLIC ACID, AND RECOVERING THE HYDROXYCARBOXYLIC ACID.
Claim 2
Dependent Claim
127 words
A PROCESS COMPRISING REACTING A HYDROXYCARBOXYLIC ACID CONTAINED IN AQUEOUS SOLUTION WITH AN ORGANIC AMINE SELECTED FROM THE GROUP CONSISTING OF A SECONDARY AND TERTIARY ALKYL AMINE CONTAINING FROM 5 TO 12 CARBON ATOMS IN EACH ALKYL GROUP TO FORM AN ORGANIC SOLVENT SOLUBLE SALT OF SAID HYDROXYCARBOXYLIC ACID AND THE AMINE, SAID REACTION BEING CONDUCTED IN THE PRESENCE OF AN ORGANIC, WATER IMMISCIBLE SOLVENT ADAPTED TO DISSOLVE SAID SALT OF SAID AMINE AND HYDROXYCARBOXYLIC ACID AND SELECTED FROM THE GROUP CONSISTING OF AN ALCOHOL CONTAINING AT LEAST FOUR CARBON ATOMS AND CHLOROFORM, SEPARATING THE RESULTING SOLUTION OF THE FORMED SALT OF THE AMINE AND HYDROXYCARBOXYLIC ACID IN THE ORGANIC WATER IMMISCIBLE SOLVENT, DECOMPOSING SAID SALT TO LIBERATE THE FREE HYDROXYCARBOXYLIC ACID, AND RECOVERING THE HYDROXYCARBOXYLIC ACID.
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) | 1954-01-29 | 1954-07-31 | 1955-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-01-29 | 1958-07-31 | 1959-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-01-29 | 1962-07-31 | 1963-01-30 | $7700.00 | Window Closed / Lapsed |