US2797216A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of caprolagtam
Assignee: —
•
Filing: —
•
Granted: 1957-06-25
•
Expires: 1974-06-25
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:13
CPC Classifications
C; C07; C07D; C07D201/00; C07D201/02; C07D201/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
76 words
A METHOD FOR PRODUCING CAPROLACTAM WHICH COMPRISES CONTACTING A SOLUTION OF CYCLOHEXANONE OXIME IN CYCLOHEXANE WITH DRY HYDROGEN CHLORIDE, TO FORM AN INSOLUBLE CYCLOHEXANONE OXIME HYDROCHLORIDE, SEPARATING THE HYDROCHLORIDE FROM THE CYCLOHEXANE PHASE, CONTACTING THE HYDROCHLORIDE WITH SULFURIC ACID OF ABOUT 75 TO 100% STRENGTH WHILE MAINTAINING THE TEMPERATURE OF THE RESULTING MIXTURE FROM ABOUT 60* TO 120*C. TO EFFECT REARRANGEMENT OF THE HYDROCHLORIDE TO CAPROLACTAM, EVOLVING HYDROGEN CHLORIDE FROM THE REARRANGING MIXTURE, AND RECOVERING CAPROLACTAM.
Claim 2
Independent Claim
76 words
A METHOD FOR PRODUCING CAPROLACTAM WHICH COMPRISES CONTACTING A SOLUTION OF CYCLOHEXANONE OXIME IN CYCLOHEXANE WITH DRY HYDROGEN CHLORIDE, TO FORM AN INSOLUBLE CYCLOHEXANONE OXIME HYDROCHLORIDE, SEPARATING THE HYDROCHLORIDE FROM THE CYCLOHEXANE PHASE, CONTACTING THE HYDROCHLORIDE WITH SULFURIC ACID OF ABOUT 75 TO 100% STRENGTH WHILE MAINTAINING THE TEMPERATURE OF THE RESULTING MIXTURE FROM ABOUT 60* TO 120*C. TO EFFECT REARRANGEMENT OF THE HYDROCHLORIDE TO CAPROLACTAM, EVOLVING HYDROGEN CHLORIDE FROM THE REARRANGING MIXTURE, AND RECOVERING CAPROLACTAM.
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) | 1960-06-24 | 1960-12-24 | 1961-06-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-06-24 | 1964-12-24 | 1965-06-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-06-24 | 1968-12-24 | 1969-06-25 | $7700.00 | Window Closed / Lapsed |