US2813858A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for purifying epsilon-caprolactam
Assignee: Honeywell International Inc
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Filing: 1954-08-26
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Granted: 1957-11-19
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Expires: 1974-08-26
Abstract
No abstract record available.
Inventors
- 👤 George G Joris
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:30
CPC Classifications
C; C07; C07D; C07D201/00; C07D201/16
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
70 words
A PROCESS FOR PURIFYING EPSILON-CAPROLACTAM, WHICH COMPRIESE PARTIALLY FREEZING MOLTEN EPSILON-CAPROLACTAM, CONTAINING DISSOLVED THEREIN AS FREEZING POINT DEPRESSOR AT LEAST 0.1 GRAM MOL OF AT LEAST ONE LACTAM-SOLUBLE MATERIAL PER 1000 GRAMS OF EPSILON-CAPROLACTAM, INTO A SLUSH OF CRYSTALLINE LACTAM AND MELT, SAID MELT HAVING CONCENTRATION OF SAID LACTAM-SOLUBLE MATERIAL NOT IN EXCESS OFF ABOUT 30 MOLAL WITH RESPECT TO THE EPSILON-CAPROLACTAM THEREIN; AND SEPARATING CRYSTALLINE LACTAM FROM SAID MELT.
Claim 2
Dependent Claim
70 words
A PROCESS FOR PURIFYING EPSILON-CAPROLACTAM, WHICH COMPRIESE PARTIALLY FREEZING MOLTEN EPSILON-CAPROLACTAM, CONTAINING DISSOLVED THEREIN AS FREEZING POINT DEPRESSOR AT LEAST 0.1 GRAM MOL OF AT LEAST ONE LACTAM-SOLUBLE MATERIAL PER 1000 GRAMS OF EPSILON-CAPROLACTAM, INTO A SLUSH OF CRYSTALLINE LACTAM AND MELT, SAID MELT HAVING CONCENTRATION OF SAID LACTAM-SOLUBLE MATERIAL NOT IN EXCESS OFF ABOUT 30 MOLAL WITH RESPECT TO THE EPSILON-CAPROLACTAM THEREIN; AND SEPARATING CRYSTALLINE LACTAM FROM SAID MELT.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-11-18 | 1961-05-20 | 1961-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-11-18 | 1965-05-20 | 1965-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-11-18 | 1969-05-20 | 1969-11-19 | $7700.00 | Window Closed / Lapsed |