Patent US2591032A successfully refreshed from Google Patents.
US2591032A
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Methods for growing ethylenediamine tartrate crystals
Assignee: AT&T Inc
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Filing: 1950-08-11
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Granted: 1952-04-01
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Expires: 1970-08-11
Abstract
No abstract record available.
Inventors
- 👤 Albert C Walker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:23
CPC Classifications
C; C30; C30B; C30B29/00; C30B29/54; C30B29/56; C30B7/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
48 words
A PROCESS COMPRISING GROWING ETHYLENDIAMINE TARTRATE CRYSTALS FROM SEEDS IN A MOTHER LIQUOR SUPERSATURATED WITH ETHYLENEDIAMINE TARTRATE, WHICH SOLUTION IS MAINTAINED ALKALINE AT A PH OF FROM 5.5 TO 8 BY THE PRESENCE OF AMMONIUM HYDROXIDE AND AT A TEMPERATURE OF FROM ABOUT 40.6* C. TO 50* C.
Claim 2
Dependent Claim
48 words
A PROCESS COMPRISING GROWING ETHYLENDIAMINE TARTRATE CRYSTALS FROM SEEDS IN A MOTHER LIQUOR SUPERSATURATED WITH ETHYLENEDIAMINE TARTRATE, WHICH SOLUTION IS MAINTAINED ALKALINE AT A PH OF FROM 5.5 TO 8 BY THE PRESENCE OF AMMONIUM HYDROXIDE AND AT A TEMPERATURE OF FROM ABOUT 40.6* C. TO 50* C.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-04-01 | 1955-10-01 | 1956-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-04-01 | 1959-10-01 | 1960-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-04-01 | 1963-10-01 | 1964-04-01 | $7700.00 | Window Closed / Lapsed |