Patent US2204539A successfully refreshed from Google Patents.
US2204539A
Expired / Lapsed
US
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Process of effecting cation exchange
Assignee: IG Farbenindustrie AG
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Filing: 1938-06-21
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Granted: 1940-06-11
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Expires: 1958-06-21
Abstract
No abstract record available.
Inventors
- 👤 Wassenegger Hans
- 👤 Jaeger Karl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:49
CPC Classifications
B; B01; B01J; B01J39/00; B01J39/08; B01J39/16; B01J39/18; B01J39/19; B01J39/04; B01J39/05
Claims Analysis
Total Claims: 0
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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) | 1943-06-11 | 1943-12-11 | 1944-06-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1947-06-11 | 1947-12-11 | 1948-06-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1951-06-11 | 1951-12-11 | 1952-06-11 | $7700.00 | Window Closed / Lapsed |