Patent US3720577A successfully refreshed from Google Patents.
US3720577A
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US
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Chlorine dioxide-peracetic acid-chlorine dioxide pulp bleaching sequence
Assignee: International Paper Co
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Filing: 1970-05-25
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Granted: 1973-03-13
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Expires: 1990-05-25
Abstract
Abstract A CHEMICAL PULP CAN BE BLEACHED WITH CHLORINE DIOXIDE IN THE FIRST STAGE AND PERACETIC ACID IN THE SECOND STAGE TO A BRIGHTNESS OF 60% OF ABOUT. THE ADDITIVE OF A CHLORINE DIOXIDE THIRD STAGE RESULTS IN A FULLY PLEACHED PULPHAVING A BRIGHTNESS OF 80% OR ABOUT IN JUST 3 STAGES, COMPARED TO THE USUAL 5 OR 6 STAGE SEQIEMCES.
Inventors
- 👤 S Roymoulik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 07:29
CPC Classifications
D; D21; D21C; D21C9/00; D21C9/10; D21C9/12; D21C9/14; D21C9/144
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) | 1976-03-12 | 1976-09-11 | 1977-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-12 | 1980-09-11 | 1981-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-12 | 1984-09-11 | 1985-03-13 | $7700.00 | Window Closed / Lapsed |