US4415124A
Expired / Lapsed
US
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Method for the production of micropowders from cellulose ethers or cellulose
Assignee: Henkel AG and Co KGaA
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Filing: 1981-10-07
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Granted: 1983-11-15
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Expires: 2001-10-07
Abstract
Abstract A method for the production of micropowders from cellulose ethers or cellulose comprising (a) subjecting a cellulose ether or a cellulose having a fine-fiber, cottony or woolly structure to a consolidation or embrittlement sufficient whereby in one mill pass through a jet mill under standard conditions 98% by weight of the consolidated or embrittled material charged is recovered as a powder of less than 100μ, and (b) subjecting the consolidated or embrittled material to a grinding step producing a size reduction sufficient that a grain size distribution with at least 90% by weight of less than 125μ is attained.
Inventors
- 👤 Franz-Josef Carduck
- 👤 Wilfried Rahse
- 👤 Willi Wust
- 👤 Hans Pabel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 15:29
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/12; C08J2301/00
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
131 words
A method for the production of micropowders from cellulose ethers or cellulose comprising: (a) subjecting a cellulose ether or a cellulose having a fine-fiber, cottony or woolly structure to a consolidation or embrittlement sufficient whereby in one mill pass through a jet mill under standard conditions 98% by weight of the consolidated or embrittled material charged is recovered as a powder of less than 100μ, and (b) subjecting the consolidated or embrittled material in the form of scales to a grinding step of one mill pass through a jet mill or a pinned disk mill or a baffle plate mill, producing a size reduction sufficient that a grain size distribution with at least 90% by weight of less than 125μ is attained, with a macromolecular degradation of from 2% to 26%.
Claim 2
Independent Claim
131 words
A method for the production of micropowders from cellulose ethers or cellulose comprising: (a) subjecting a cellulose ether or a cellulose having a fine-fiber, cottony or woolly structure to a consolidation or embrittlement sufficient whereby in one mill pass through a jet mill under standard conditions 98% by weight of the consolidated or embrittled material charged is recovered as a powder of less than 100μ, and (b) subjecting the consolidated or embrittled material in the form of scales to a grinding step of one mill pass through a jet mill or a pinned disk mill or a baffle plate mill, producing a size reduction sufficient that a grain size distribution with at least 90% by weight of less than 125μ is attained, with a macromolecular degradation of from 2% to 26%.
Claim 3
Dependent Claim
35 words
The method of claim 1 wherein said consolidated or embrittled material is ground in a jet mill in step (b) and a grain size distribution with at least 98% of less than 100μ is attained.
Claim 4
Dependent Claim
29 words
The method of claim 1, step (a), wherein said consolidation or embrittlement is effected in a vibration or ball mill, optionally with a cooling system, or a pellet press.
Claim 5
Dependent Claim
37 words
The method of claim 1 or 2 or 3 wherein simultaneously with said grinding step (b) a drying of said cellulose ether or cellulose to a water content of from 0.5% to 12% by weight is effected.
Claim 6
Dependent Claim
19 words
The method of claim 4 wherein said water content after said drying is from 3% to 6% by weight.
Claim 7
Dependent Claim
37 words
The method of claim 1 or 2 or 3 wherein a cellulose ether is employed that has been consolidated or embrittled in step (a) to have a bulk weight of between about 280 and about 480 gm/l.
Claim 8
Dependent Claim
17 words
The method of claim 6 wherein said bulk weight is between about 320 and about 370 gm/l.
Claim 9
Dependent Claim
34 words
The method of claim 1 or 2 or 3 wherein said cellulose ether or cellulose having a fine-fiber, cottony or woolly structure has a bulk weight of between about 30 and about 280 gm/l.
Claim 10
Dependent Claim
16 words
The method of claim 8 wherein said bulk weight is between 75 and about 160 gm/l.
Claim 11
Dependent Claim
64 words
The method of claim 1 or 2 or 3 wherein said cellulose ether or cellulose having a fine-fiber, cottony or woolly structure has a moisture content of from about 0.5% to about 20% by weight and is selected from the group consisting of cellulose linters, spruce cellulose, beech cellulose, lower alkyl cellulose ether, lower alkyl-hydroxy lower alkyl cellulose ether and carboxy-lower alkyl cellulose ether.
Claim 12
Dependent Claim
18 words
The method of claim 10 wherein said moisture content is from about 8% to about 15% by weight.
Claim 13
Dependent Claim
49 words
The method of claim 1 or 2 or 3 wherein said consolidation or embrittlement in step (a) is conducted with a pellet press and said cellulose ether or cellulose having a fine-fiber, cottony or woolly structure has a moisture content of from about 20% to about 80% by weight.
Claim 14
Dependent Claim
18 words
The method of claim 12 wherein said moisture content is from about 40% to about 60% by weight.
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) | 1986-11-14 | 1987-05-16 | 1987-11-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-11-14 | 1991-05-16 | 1991-11-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-11-14 | 1995-05-16 | 1995-11-15 | $7700.00 | Window Closed / Lapsed |