Patent US2215555A successfully refreshed from Google Patents.
US2215555A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Chemical conversion of leuco compounds
Assignee: Celanese Corp
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Filing: 1937-09-11
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Granted: 1940-09-24
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Expires: 1957-09-11
Abstract
No abstract record available.
Inventors
- 👤 Lord Geoffrey
- 👤 Reeves George
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:30
CPC Classifications
C; C09; C09B; C09B57/00; C09B1/00; C09B1/02; C09B1/06; C09B1/08; C09B1/16; C09B1/20; D; D06; D06P; D06P1/00; D06P1/22; D06P1/222
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) | 1943-09-24 | 1944-03-25 | 1944-09-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1947-09-24 | 1948-03-25 | 1948-09-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1951-09-24 | 1952-03-25 | 1952-09-24 | $7700.00 | Window Closed / Lapsed |