Patent US2219581A successfully refreshed from Google Patents.
US2219581A
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US
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Decolorizing and filtering agent
Assignee: DICALITE Co
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Filing: 1938-04-04
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Granted: 1940-10-29
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Expires: 1958-04-04
Abstract
No abstract record available.
Inventors
- 👤 Richard W Schmidt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:35
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/02; B01J20/10; B01J20/14; B01J20/28; B01J20/28014; B01J20/2803; B01J20/30; B01J20/3021; B01J20/3042; B01J20/3078; B01J20/32; B01J20/3202; B01J20/3204; B01J20/3214; B01J20/3223; B01J20/3231; B01J20/3234; B01J20/324; C; C01; C01B; C01B32/00; C01B32/30; C01B32/354; C01B32/372; B01J2220/00; B01J2220/40; B01J2220/42; B01J2220/48; B01J2220/4812; Y; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/917
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) | 1943-10-29 | 1944-04-29 | 1944-10-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1947-10-29 | 1948-04-29 | 1948-10-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1951-10-29 | 1952-04-29 | 1952-10-29 | $7700.00 | Window Closed / Lapsed |