US2884457A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Separation of isomeric xylylene diamines
Assignee: California Research LLC
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Filing: 1955-03-15
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Granted: 1959-04-28
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Expires: 1975-03-15
Abstract
No abstract record available.
Inventors
- 👤 Louis L Ferstandig
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 22:57
CPC Classifications
C; C07; C07C; C07C209/00; C07C209/44; C07C209/48; C07C209/82; C07C209/84; C07C209/86; C07C211/00; C07C211/01; C07C211/26; C07C211/27
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
64 words
A PROCESS FOR THE SEPARATION OF A XYLYLENEDIAMINE DIHYDROCHLORIDE MIXTURE OF META-XYLYLENEDIAMINE DIHYDROCHLORIDE AND PARA-XYLYLENEDIAMINE DIHYDROCHLORIDE CONTAINING FROM ABOUT 5 TO 30% OF THE LATTER DIHYDROCHLORIDE, WHICH COMPRISES ADDING TO SAID MIXTURE AN AMOUNT OF WATER SUFFICIENT TO FORM AN AQUEOUS PHASE BUT INSUFFICIENT TO DISSOLVE ALL OF THE XYLYLENEDIAMINE DIHYDROCHLORIDES, THEREBY FORMING AN AQUEOUS PHASE AND A SOLID PHASE, AND SEPARATING THE PHASES.
Claim 2
Dependent Claim
64 words
A PROCESS FOR THE SEPARATION OF A XYLYLENEDIAMINE DIHYDROCHLORIDE MIXTURE OF META-XYLYLENEDIAMINE DIHYDROCHLORIDE AND PARA-XYLYLENEDIAMINE DIHYDROCHLORIDE CONTAINING FROM ABOUT 5 TO 30% OF THE LATTER DIHYDROCHLORIDE, WHICH COMPRISES ADDING TO SAID MIXTURE AN AMOUNT OF WATER SUFFICIENT TO FORM AN AQUEOUS PHASE BUT INSUFFICIENT TO DISSOLVE ALL OF THE XYLYLENEDIAMINE DIHYDROCHLORIDES, THEREBY FORMING AN AQUEOUS PHASE AND A SOLID PHASE, AND SEPARATING THE PHASES.
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) | 1962-04-27 | 1962-10-27 | 1963-04-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-04-27 | 1966-10-27 | 1967-04-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-04-27 | 1970-10-27 | 1971-04-28 | $7700.00 | Window Closed / Lapsed |