US3284283A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of wood pulps including treatment of cellulosic fibers with bisulfite ion followed by alkali metal borohydride
Assignee: FMC Corp
•
Filing: 1964-02-17
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Granted: 1966-11-08
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Expires: 1984-02-17
Abstract
No abstract record available.
Inventors
- 👤 Robert R Kindron
- 👤 Louis P Cartsunis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 01:06
CPC Classifications
D; D21; D21B; D21B1/00; D21B1/04; D21B1/12; D21B1/14; D21B1/16; D21C; D21C9/00; D21C9/10; D21C9/1026; D21C9/1036; D21C9/1047; D21C9/1084
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
83 words
METHOD OF PRODUCING CELLULOSIC PULPS HAVING HIGH BRIGHTNESS, COMPRISING IMPREGNATING CELLULOSIC FIBERS WITH AN AQUEOUS SOLUTION CONTAINING BISULFITE ION AND HAVING A PH OF 2 TO 7 TO PROVIDE AT LEAST ABOUT 0.04% OF SAID BISULFITE ION ON THE FIBERS, CONTACTING THE RESULTING BUSULFITE ION-IMPREGNATED FIBERS CONTAINING SAID AT LEAST ABOUT 0.04% OF BISULFITE ION WITH 0.01 TO 0.5% OF THE WEIGHT OF THE FIBERS OF AN ALKALI METAL BOROHYDRIDE, AND PERMITTING THE REAGENTS TO ACT ON THE FIBERS TO INCREASE THEIR BRIGHTNESS.
Claim 2
Dependent Claim
83 words
METHOD OF PRODUCING CELLULOSIC PULPS HAVING HIGH BRIGHTNESS, COMPRISING IMPREGNATING CELLULOSIC FIBERS WITH AN AQUEOUS SOLUTION CONTAINING BISULFITE ION AND HAVING A PH OF 2 TO 7 TO PROVIDE AT LEAST ABOUT 0.04% OF SAID BISULFITE ION ON THE FIBERS, CONTACTING THE RESULTING BUSULFITE ION-IMPREGNATED FIBERS CONTAINING SAID AT LEAST ABOUT 0.04% OF BISULFITE ION WITH 0.01 TO 0.5% OF THE WEIGHT OF THE FIBERS OF AN ALKALI METAL BOROHYDRIDE, AND PERMITTING THE REAGENTS TO ACT ON THE FIBERS TO INCREASE THEIR BRIGHTNESS.
References Cited (Backward Citations)
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Cited
US2826478A
Cited
US2882147A
Cited
US2991152A
Cited
US3023140A
Cited
US3100732A
Cited
US3173748A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-11-07 | 1970-05-09 | 1970-11-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-11-07 | 1974-05-09 | 1974-11-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-11-07 | 1978-05-09 | 1978-11-08 | $7700.00 | Window Closed / Lapsed |