Patent US2562861A successfully refreshed from Google Patents.
US2562861A
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Mandelic acid purification involving production of complex alkali metal salts thereof
Assignee: Nepera Chemical Co Inc
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Filing: 1949-11-23
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Granted: 1951-07-31
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Expires: 1969-11-23
Abstract
No abstract record available.
Inventors
- 👤 Bernard F Duesel
- 👤 Gister Sidney
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 17:00
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/41; C07C51/412; C07C51/42; C07C51/43
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
95 words
THE PROCESS WHICH COMPRISES MIXING CRUDE MANDELIC ACID CONTAINING ORGANIC IMPURITIES RESULTING FROM THE PROCESS USED IN ITS PREPARATION WITH AN AQUEOUS ALKALINE SOLUTION OF AN ALKALI METAL COMPOUND, AT A PH VALUE OF ABOUT 3.5 THEREBY FORMING A COMPLEX ALKALI METAL SALT OF MANDELIC ACID IN THE REACTION SOLUTION, CRYSTALLIZING THE SAID SALT OUT OF THE SOLUTION, SEPARATING THE SOLUTION FROM THE CRYSTALS AND REMOVING THE ORGANIC IMPURITIES FROM THE LATTER BY DISSOLVING THEM OUT IN AN ORGANIC SOLVENT THEREBY OBTAINING THE MANDELIC ACID COMPONENT IN SUBSTANTIALLY PURE FORM FREE OF THE ORGANIC IMPURITIES.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-07-30 | 1955-01-29 | 1955-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-07-30 | 1959-01-29 | 1959-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-07-30 | 1963-01-29 | 1963-07-31 | $7700.00 | Window Closed / Lapsed |