US2448029A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of preparing phenolsulfonic acid-formaldehyde ion exchange agents
Assignee: Dow Chemical Co
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Filing: 1947-02-24
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Granted: 1948-08-31
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Expires: 1967-02-24
Abstract
No abstract record available.
Inventors
- 👤 Heusted George Beal
- 👤 William C Bauman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:52
CPC Classifications
B; B01; B01J; B01J39/00; B01J39/08; B01J39/16; B01J39/18; B01J39/19
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) | 1951-08-31 | 1952-03-01 | 1952-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-08-31 | 1956-03-01 | 1956-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-08-31 | 1960-03-01 | 1960-08-31 | $7700.00 | Window Closed / Lapsed |