Patent US3235600A successfully refreshed from Google Patents.
US3235600A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reduction of diaminocyclohexane concentration in crude hexamethylenedi-amine
Assignee: Monsanto Co
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Filing: 1962-11-28
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Granted: 1966-02-15
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Expires: 1982-11-28
Abstract
No abstract record available.
Inventors
- 👤 Phillip W Evans
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 16:42
CPC Classifications
C; C07; C07C; C07C209/00; C07C209/44; C07C209/48
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
79 words
IN THE CATALYTIC HYDROGENATION OF ADIPONITRILE TO HEXAMETHYLENEDIAMINE AT A TEMPERATURE FROM 120 TO 170* C. AND AT A PRESSURE FROM 4,000 TO 6,000 POUNDS PER SQUARE INCH GAUGE A METHOD FOR REDUCING THE AMOUNT OF 1,2-DIAMINOCYCLOHEXANE PRESENCE IN CRUDE HEXAMETHYLENEDIAMINE FORMED BY SAID CATALYTIC HYDROGENATION COMPRISING, IN COMBINATION, CONTACTING SAID ADIPONITRILE DURING SAID CATALYTIC HYDROGENATION WITH AT LEAST ONE COMPOUND CAPABLE OF SUPPRESSING THE FORMATION OF 1,2-DIAMINOCYCLOHEXANE SELECTED FROM THE GROUP CONSISTING OF HEXAMETHYLENEDIAMINE CARBONATE AND AMINOCAPRONITRILE CARBAMATE.
Claim 2
Dependent Claim
79 words
IN THE CATALYTIC HYDROGENATION OF ADIPONITRILE TO HEXAMETHYLENEDIAMINE AT A TEMPERATURE FROM 120 TO 170* C. AND AT A PRESSURE FROM 4,000 TO 6,000 POUNDS PER SQUARE INCH GAUGE A METHOD FOR REDUCING THE AMOUNT OF 1,2-DIAMINOCYCLOHEXANE PRESENCE IN CRUDE HEXAMETHYLENEDIAMINE FORMED BY SAID CATALYTIC HYDROGENATION COMPRISING, IN COMBINATION, CONTACTING SAID ADIPONITRILE DURING SAID CATALYTIC HYDROGENATION WITH AT LEAST ONE COMPOUND CAPABLE OF SUPPRESSING THE FORMATION OF 1,2-DIAMINOCYCLOHEXANE SELECTED FROM THE GROUP CONSISTING OF HEXAMETHYLENEDIAMINE CARBONATE AND AMINOCAPRONITRILE CARBAMATE.
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) | 1969-02-14 | 1969-08-16 | 1970-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-02-14 | 1973-08-16 | 1974-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-02-14 | 1977-08-16 | 1978-02-15 | $7700.00 | Window Closed / Lapsed |