Patent US3317517A successfully refreshed from Google Patents.
US3317517A
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Process for the preparation of epsilon-caprolactam
Assignee: Teijin Ltd
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Filing: 1964-02-27
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Granted: 1967-05-02
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Expires: 1984-02-27
Abstract
No abstract record available.
Inventors
- 👤 Mifune Akira
- 👤 Ishimoto Sachio
- 👤 Ikeda Osamu
- 👤 Matsui Hideo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:29
CPC Classifications
C; C07; C07D; C07D201/00; C07D201/02; C07D201/08; B; B01; B01J; B01J23/00; B01J23/38; B01J23/40; B01J23/70; B01J27/00; B01J27/20; B01J27/22; B01J23/90; B01J37/00; B01J37/02; B01J37/0201; B01J37/03; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/52; Y02P20/582; Y02P20/584
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
60 words
A PROCESS FOR THE PRODUCTION OF EPSILON-CAPROLACTAM, WHICH COMPRISES HEATING AT LEST ONE COMPOUND SELECTED FROM THE GROUP CONSISTING OF EPSILON-CAPROLACTONE, EPSILON-HYDROXY-CAPROAMIDE AND AMIDE-FORMING DERIVATIVES OF EPSILON-HYDROXYCAPROIC ACID, TOGETHER WITH AQUEOUS AMMONIA WHOSE AMMONIA CONCENTRATIONIS FROM 8 TO 35% BY WEIGHT, TO A TEMPERATURE WITHIN THE RANGE OF 200% TO 420%C. IN AN ATMOSPHERE OF HYDROGEN OR HYDROGEN-CONTAINING INERT GAS.
Claim 2
Dependent Claim
60 words
A PROCESS FOR THE PRODUCTION OF EPSILON-CAPROLACTAM, WHICH COMPRISES HEATING AT LEST ONE COMPOUND SELECTED FROM THE GROUP CONSISTING OF EPSILON-CAPROLACTONE, EPSILON-HYDROXY-CAPROAMIDE AND AMIDE-FORMING DERIVATIVES OF EPSILON-HYDROXYCAPROIC ACID, TOGETHER WITH AQUEOUS AMMONIA WHOSE AMMONIA CONCENTRATIONIS FROM 8 TO 35% BY WEIGHT, TO A TEMPERATURE WITHIN THE RANGE OF 200% TO 420%C. IN AN ATMOSPHERE OF HYDROGEN OR HYDROGEN-CONTAINING INERT GAS.
References Cited (Backward Citations)
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US3000879A
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US3000877A
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US2817646A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1970-05-01 | 1970-10-31 | 1971-05-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-05-01 | 1974-10-31 | 1975-05-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-05-01 | 1978-10-31 | 1979-05-02 | $7700.00 | Window Closed / Lapsed |