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US2688014A
Expired / Lapsed
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Process for the manufacture of epsilon-thiocaprolactam
Assignee: EIDP Inc
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Filing: 1953-01-23
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Granted: 1954-08-31
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Expires: 1973-01-23
Abstract
No abstract record available.
Inventors
- 👤 Walter V Wirth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 04:09
CPC Classifications
C; C07; C07D; C07D223/00; C07D223/02; C07D223/06
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
57 words
A PROCESS FOR PREPARING EPSILON-THICAPROLACTAM FROM EPSILON-CAPROLACTAM WHICH COMPRISES HEATING 1 MOL OF EPSILON-CAPROLACTAN WITH FROM 0.6 TO 1.0 MOL WATER AT FROM 50* TO 60* C. TO EFFECT COMPLETE SOLUTION AND ADDING FROM 0.3 TO 0.35 MOL OF PHOSPHORUS PENTASULFIDE WHILE MAINTAINING THE TEMPERATURE SUFFICIENTLY HIGH TO PREVENT CRYSTALLIZATION OF THE EPSILON-THIOCAPROLACTAM AT THE TEMPERATURE EMPLOYED.
Claim 2
Dependent Claim
57 words
A PROCESS FOR PREPARING EPSILON-THICAPROLACTAM FROM EPSILON-CAPROLACTAM WHICH COMPRISES HEATING 1 MOL OF EPSILON-CAPROLACTAN WITH FROM 0.6 TO 1.0 MOL WATER AT FROM 50* TO 60* C. TO EFFECT COMPLETE SOLUTION AND ADDING FROM 0.3 TO 0.35 MOL OF PHOSPHORUS PENTASULFIDE WHILE MAINTAINING THE TEMPERATURE SUFFICIENTLY HIGH TO PREVENT CRYSTALLIZATION OF THE EPSILON-THIOCAPROLACTAM AT THE TEMPERATURE EMPLOYED.
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) | 1957-08-30 | 1958-03-01 | 1958-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-08-30 | 1962-03-01 | 1962-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-08-30 | 1966-03-01 | 1966-08-31 | $7700.00 | Window Closed / Lapsed |