Patent US2212969A successfully refreshed from Google Patents.
Patent US3452222A successfully refreshed from Google Patents.
US2773902A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydrogenation of phthalonitriles
Assignee: California Research LLC
•
Filing: 1954-05-10
•
Granted: 1956-12-11
•
Expires: 1974-05-10
Abstract
No abstract record available.
Inventors
- 👤 Charles D Heaton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 23:49
CPC Classifications
C; C07; C07C; C07C209/00; C07C209/44; C07C209/48
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
68 words
PROCESS OF PREPARING OF XYLYLENE DIAMINE WHICH COMPRISES HYDROGENATING A PHTHALONITRILE DINITRILE UNDER HYDROGENATION CONDITIONS OF TEMPERATURE AND PRESSURE IN THE PRESENCE OF A COBALT HYDROGENATION CATALYST AND ABOUT 1 TO 5 PARTS OF EACH PART OF PHTHALONITRILE, BY WEIGHT, OF A LIQUID AMMONIA-WATER REACTION MEDIUM, THE AMMONIA AND WATER BEING PRESENT DURING REACTION IN A WEIGHT RATIO OF 50 TO 95 AMMONIA TO 50 TO 5 WATER.
Claim 2
Dependent Claim
68 words
PROCESS OF PREPARING OF XYLYLENE DIAMINE WHICH COMPRISES HYDROGENATING A PHTHALONITRILE DINITRILE UNDER HYDROGENATION CONDITIONS OF TEMPERATURE AND PRESSURE IN THE PRESENCE OF A COBALT HYDROGENATION CATALYST AND ABOUT 1 TO 5 PARTS OF EACH PART OF PHTHALONITRILE, BY WEIGHT, OF A LIQUID AMMONIA-WATER REACTION MEDIUM, THE AMMONIA AND WATER BEING PRESENT DURING REACTION IN A WEIGHT RATIO OF 50 TO 95 AMMONIA TO 50 TO 5 WATER.
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) | 1959-12-11 | 1960-06-11 | 1960-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-12-11 | 1964-06-11 | 1964-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-12-11 | 1968-06-11 | 1968-12-11 | $7700.00 | Window Closed / Lapsed |