Patent US2256528A successfully refreshed from Google Patents.
US2256528A
Expired / Lapsed
US
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Material for polishing, cleaning, or the like and method of making the same
Assignee: American Optical Corp
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Filing: 1939-05-01
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Granted: 1941-09-23
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Expires: 1959-05-01
Abstract
No abstract record available.
Inventors
- 👤 Louis F Rowe
- 👤 Carl G Silverberg
- 👤 Alexis G Pincus
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 00:12
CPC Classifications
B; B01; B01J; B01J21/00; B01J21/16; C; C09; C09K; C09K3/00; C09K3/14
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) | 1944-09-22 | 1945-03-24 | 1945-09-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1948-09-22 | 1949-03-24 | 1949-09-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1952-09-22 | 1953-03-24 | 1953-09-23 | $7700.00 | Window Closed / Lapsed |