US3719552A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Bleaching of lignocellulosic materials with oxygen in the presence of a peroxide
Assignee: Wyeth Holdings LLC
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Filing: 1971-06-18
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Granted: 1973-03-06
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Expires: 1991-06-18
Abstract
Abstract THE RATE AT WHICH SULFATE-PROCESS PULP IS BRIGHTENED BY OXYGENATED AQUEOUS MEDIUM IS ACCELARATED BY THE PRESENCE IN THE MEDIUM OF A DISSOLVED PEROXIDE WHEN THE PH OF THE MEDIUM IS IN EXCESS OF 11.
Inventors
- 👤 C Farley
- 👤 M Grayson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 07:22
CPC Classifications
D; D21; D21C; D21C9/00; D21C9/10; D21C9/1026; D21C9/1036
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) | 1976-03-05 | 1976-09-04 | 1977-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-05 | 1980-09-04 | 1981-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-05 | 1984-09-04 | 1985-03-06 | $7700.00 | Window Closed / Lapsed |