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US2640080A
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Preparation of primary diamines
Assignee: EIDP Inc
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Filing: 1947-10-18
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Granted: 1953-05-26
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Expires: 1967-10-18
Abstract
No abstract record available.
Inventors
- 👤 Tar De Los F De
- 👤 Pome Charles J Le
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 13:08
CPC Classifications
C; C07; C07C; C07C209/00; C07C209/04; C07C209/06; C07C209/08; C07C211/00; C07C211/43; C07C211/44; C07C211/49; C07C211/50
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
117 words
A PROCESS FOR THE SYNTHESIS OF DIPRIMARY DIAMINES WHICH COMPRISES REACTING AMMONIA IN THE LIQUID PHASE UNDER ANHYDROUS CONDITIONS WITH A DIHALOHYDROCARBON, HAVING NOT MORE THAN 1I CARBON ATOMS PER MOLECULE, IN WHICH BOTH HALOGEN ATOMS ARE OF THE CLASS CONSISTINT OF CHLORINE AND BROMINE, EACH OF THE SAID HALOGEN ATOMS BEING SEPARATED BY A METHYLENE GROUP FROM AN AROMATIC NUCLEUS, AT A TEMPERATURE OF 30* TO 60* C., THE INITIAL MOL RATIO OF AMMONIA TO THE SAID DIHALIDE BEING FROM 250:1 TO 1200:1, FOR A REACTION PERIOD NOT EXCEEDING 70 MINUTES, WHEREBY A HYDROHALIDE OF A DIPRIMARY DIAMINE IS PRODUCED AS THE CHIEF REACTION PRODUCT, AND THEREAFTER SEPARATING THE SAID DIPRIMARY DIAMINE FROM THE RESULTING MIXTURE.
References Cited (Backward Citations)
US2072015A
Cited
US2113640A
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GB482008A
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US2172822A
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US2216548A
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US2411142A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-05-25 | 1956-11-24 | 1957-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-05-25 | 1960-11-24 | 1961-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-05-25 | 1964-11-24 | 1965-05-26 | $7700.00 | Window Closed / Lapsed |