Patent DE587525C successfully refreshed from Google Patents.
US2487899A
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US
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Process of wax sizing papermaking fibers using a cationic surface active agent
Assignee: Nopco Chemical Co
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Filing: 1945-05-10
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Granted: 1949-11-15
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Expires: 1965-05-10
Abstract
No abstract record available.
Inventors
- 👤 Laurence R Sherman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 09:29
CPC Classifications
D; D21; D21H; D21H23/00; D21H17/00; D21H17/03; D21H17/05; D21H17/07; D21H17/60; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2933
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-11-14 | 1953-05-16 | 1953-11-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-11-14 | 1957-05-16 | 1957-11-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-11-14 | 1961-05-16 | 1961-11-15 | $7700.00 | Window Closed / Lapsed |