Patent US2642459A successfully refreshed from Google Patents.
US2642459A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production and purification of amino acids
Assignee: Dow Chemical Co
•
Filing: 1948-12-08
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Granted: 1953-06-16
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Expires: 1968-12-08
Abstract
No abstract record available.
Inventors
- 👤 Halbert C White
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 10:09
CPC Classifications
C; C07; C07C; C07C227/00; C07C227/04; C07C227/06; C07C227/08
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
14 words
IN A METHOD WHEREIN AN AQUEOUS SOLUTION OF A HYDANTOIN, HAVING THE GENERAL FORMULA:
Claim 2
Dependent Claim
14 words
IN A METHOD WHEREIN AN AQUEOUS SOLUTION OF A HYDANTOIN, HAVING THE GENERAL FORMULA:
References Cited (Backward Citations)
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US2109929A
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US2384817A
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Cited
US2446192A
Cited
US2480644A
Cited
US2456742A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-06-15 | 1956-12-15 | 1957-06-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-06-15 | 1960-12-15 | 1961-06-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-06-15 | 1964-12-15 | 1965-06-16 | $7700.00 | Window Closed / Lapsed |