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US3017316A
Expired / Lapsed
US
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Method of bleaching wood pulp with chlorine dioxide and sodium borohydride
Assignee: Hooker Chemical Corp
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Filing: 1958-06-25
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Granted: 1962-01-16
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Expires: 1978-06-25
Abstract
No abstract record available.
Inventors
- 👤 Rapson William Howard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 21:45
CPC Classifications
D; D21; D21C; D21C9/00; D21C9/10; D21C9/1026; D21C9/1047
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
60 words
A PROCESS FOR BLEACHING WOOD PULP WHICH COMPRISES TSREATING PULP WITH AN AQUEOUS SOLUTION OF CHLORINE DIOXIDE AT FROM 50 TO 90 DEGREES CENTIGRADE, AT FROM ONE TO FIFTEEN PERCENT CONSISTENCY, FOR FROM THIRTY MINUTES TO FIVE HOURS AT A PH OF FROM ONE TO EIGHT; WASHING, AND THEN CONTACTING THE SAME PULP WITH AN AQUEOUS SOLUTION OF SODIUM BOROHYDSRODE.
Claim 2
Dependent Claim
60 words
A PROCESS FOR BLEACHING WOOD PULP WHICH COMPRISES TSREATING PULP WITH AN AQUEOUS SOLUTION OF CHLORINE DIOXIDE AT FROM 50 TO 90 DEGREES CENTIGRADE, AT FROM ONE TO FIFTEEN PERCENT CONSISTENCY, FOR FROM THIRTY MINUTES TO FIVE HOURS AT A PH OF FROM ONE TO EIGHT; WASHING, AND THEN CONTACTING THE SAME PULP WITH AN AQUEOUS SOLUTION OF SODIUM BOROHYDSRODE.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1965-01-15 | 1965-07-17 | 1966-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-01-15 | 1969-07-17 | 1970-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-01-15 | 1973-07-17 | 1974-01-16 | $7700.00 | Window Closed / Lapsed |