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Patent US2588784A successfully refreshed from Google Patents.
US2588784A
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Anion exchange resins from alkylene polyamine meta phenylene diamine, formaldehyde and acetone
Assignee: Imperial Chemical Industries Ltd
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Filing: 1950-01-09
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Granted: 1952-03-11
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Expires: 1970-01-09
Abstract
No abstract record available.
Inventors
- 👤 Whittaker Donald
- 👤 Allen Graham George
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:32
CPC Classifications
B; B01; B01J; B01J41/00; B01J41/08; B01J41/12; B01J41/13
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
84 words
AN ANION EXCHANGE RESIN OBATIANED BY REACTING TOGETHER 10 PARTS OF ALKYLENE POLYAMINE CONTAINING UP TO 40% OF WATER, FROM 2 TO 6 PARTS OF ACETONE, FROM 1 TO 3 PARTS OF METAPHENYLENE DIAMINE, AND FORMALDEHYDE EQUIVALENT TO THAT CONTAINED IN FROM 5 TO 15 PARTS OF 40% AQUEOUS FORMALDEHYDE, ALL PARTS BEING BE WEIGHT, SAID RESIN BEING CHARACTERIZED BY HAVING AN ABSORPTION CAPACITY EXCEEDING 1 MILLIEQUIVALENT PER CC., AND AN AVERAGE LOSS ON REGENERATION AFTER 25 CYCLES OF LESS THAN 0.05% PER CYCLE.
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) | 1955-03-11 | 1955-09-10 | 1956-03-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-03-11 | 1959-09-10 | 1960-03-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-03-11 | 1963-09-10 | 1964-03-11 | $7700.00 | Window Closed / Lapsed |