US4065347A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing fluffed pulp
Assignee: Essity Hygiene and Health AB
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Filing: 1976-02-20
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Granted: 1977-12-27
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Expires: 1996-02-20
Abstract
Abstract The present invention relates to fluffed pulp comprising unwashed mechanical pulp with a liquid-diffusing capacity of at least 3.5 grams liquid per gram pulp per minute, a bulk of at least 18 cm3/gram and a volume weight in blocks or bales of at most 0.8 grams/cm3. The invention also comprises a method of producing such a fluffed pulp by means of defibrating the wood and thereafter drying the same with warm air to a dry content of 80-95% by weight without subjecting the pulp to any mechanical compression.
Inventors
- 👤 Sven Ulrik Torbjorn Aberg
- 👤 Sven Gunnar Bergdahl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 03:16
CPC Classifications
D; D21; D21B; D21B1/00
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
85 words
Method of producing fluffed pulp; characterized in that wood is defibrated and thereafter dried with warm air to a dry content of 80 -95% by weight without resorting to wet pulping or mechanical compression, thereby to produce a fluffed pulp comprising an unwashed mechanical pulp having a liquid diffusing capacity of at least 3.5 grams liquid per gram pulp and minute, a bulk of at least 18 cm 3 /gram and a volume weight in blocks or bales of at most 0.8 g/cm 3 .
Claim 2
Dependent Claim
85 words
Method of producing fluffed pulp; characterized in that wood is defibrated and thereafter dried with warm air to a dry content of 80 -95% by weight without resorting to wet pulping or mechanical compression, thereby to produce a fluffed pulp comprising an unwashed mechanical pulp having a liquid diffusing capacity of at least 3.5 grams liquid per gram pulp and minute, a bulk of at least 18 cm 3 /gram and a volume weight in blocks or bales of at most 0.8 g/cm 3 .
Claim 3
Dependent Claim
49 words
Method according to claim 1, characterized in that the fluffed pulp is dried in two flash-drying stages having an intermediate terminal defibration, said fluffed pulp being dried to 60-85% by weight in the first stage and being terminally dried to 80-95% by weight dry pulp in the second stage.
Claim 4
Dependent Claim
21 words
Method according to claim 1, characterized in that defibration is carried out at a temperature of between 75° and 200° C.
Claim 5
Dependent Claim
16 words
Method according to claim 3, characterized in that said temperature is between 100° and 150° C.
Claim 6
Dependent Claim
33 words
Method of producing fluffed pulp according to claim 1, characterized in that the wood is defibrated in a refiner or a defibrator, said wood being in the form of chips, pieces or shavings.
Claim 7
Dependent Claim
24 words
Method of producing fluffed pulp according to claim 1, characterized in that defibration is carried out in the presence of a surface-active organic substance.
Claim 8
Dependent Claim
15 words
Method according to claim 1, characterized in that defibration is carried out under alkaline conditions.
References Cited (Backward Citations)
AU232954A
Cited
US3023140A
Cited
US3492199A
Cited
US3556931A
Cited
US3617439A
Cited
US3627630A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-12-26 | 1981-06-27 | 1981-12-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-12-26 | 1985-06-27 | 1985-12-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-12-26 | 1989-06-27 | 1989-12-27 | $7700.00 | Window Closed / Lapsed |