Patent JPS5220039A successfully refreshed from Google Patents.
US2072870A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cellulose derivatives
Assignee: Henry Dreyfuss Associates LLC
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Filing: 1932-12-15
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Granted: 1937-03-09
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Expires: 1952-12-15
Abstract
No abstract record available.
Inventors
- 👤 Dreyfus Henry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:04
CPC Classifications
C; C08; C08B; C08B15/00; C08B15/05; C08B15/06
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) | 1940-03-08 | 1940-09-07 | 1941-03-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1944-03-08 | 1944-09-07 | 1945-03-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1948-03-08 | 1948-09-07 | 1949-03-09 | $7700.00 | Window Closed / Lapsed |