Patent US4145391A successfully refreshed from Google Patents.
US4145391A
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Cellulose fiber process
Assignee: Rhone Poulenc Textile SA
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Filing: 1977-11-23
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Granted: 1979-03-20
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Expires: 1997-11-23
Abstract
Abstract A process for producing shaped articles of cellulose is disclosed, wherein a solution of cellulose in dimethylsulphoxide (DMSO) and formaldehyde, at a formaldehyde/cellulose weight ratio of 0.2 to 2, and at a cellulose concentration of at least 6% by weight, based on the volume of DMSO, is spun into a gaseous atmosphere containing ammonia. The process of the present invention permits the cellulosic solution to be formed into shaped articles in a very rapid and economical manner. The invention is especially useful in the production of filaments which can be used in the textile field, but other shaped articles, such as fibers, threads, films and sheets, can also be made from the cellulosic solution.
Inventors
- 👤 Henry Rodier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 15:50
CPC Classifications
D; D01; D01F; D01F2/00
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
58 words
In a process for producing shaped articles of cellulose by extruding a solution of cellulose in dimethylsulphoxide and formaldehyde, said solution containing at least 6% by weight/volume of cellulose in dimethylsulphoxide, said solution containing formaldehyde in a formaldehyde/cellulose weight ratio of between about 0.2 and 2, the improvement comprising extruding said solution into a gaseous atmosphere containing ammonia.
Claim 2
Dependent Claim
58 words
In a process for producing shaped articles of cellulose by extruding a solution of cellulose in dimethylsulphoxide and formaldehyde, said solution containing at least 6% by weight/volume of cellulose in dimethylsulphoxide, said solution containing formaldehyde in a formaldehyde/cellulose weight ratio of between about 0.2 and 2, the improvement comprising extruding said solution into a gaseous atmosphere containing ammonia.
Claim 3
Dependent Claim
17 words
Process of claim 1, wherein said gaseous atmosphere comprises said ammonia and at least one inert gas.
Claim 4
Dependent Claim
16 words
Process of claim 2, wherein said gaseous atmosphere contains up to 0.7 g/l (STP) of ammonia.
Claim 5
Dependent Claim
10 words
Process of claim 2, wherein said inert gas is nitrogen.
Claim 6
Dependent Claim
15 words
Process of claim 2, wherein said gaseous atmosphere contains a minor amount of water vapor.
Claim 7
Dependent Claim
14 words
Process of claim 1, wherein said gaseous atmosphere is heated to about 100° C.
Claim 8
Dependent Claim
16 words
Process of claim 1, wherein said cellulose has a degree of polymerization of at least 400.
Claim 9
Dependent Claim
17 words
Process of claim 1, wherein the formaldehyde/cellulose weight ratio of said solution is between 0.2 and 0.6.
Claim 10
Dependent Claim
31 words
Process according to claim 1, wherein the gaseous atmosphere is contained inside of a walled spinning chamber, wherein the said walls are heated to at least a temperature of 80° C.
Claim 11
Dependent Claim
10 words
Process of claim 1, wherein said shaped articles are filaments.
Claim 12
Dependent Claim
12 words
Process of claim 1, wherein said shaped articles are films or sheets.
References Cited (Backward Citations)
US759332A
Cited
US849823A
Cited
US842125A
Cited
US1881742A
Cited
US1652206A
Cited
US4022631A
Cited
US4028132A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-03-19 | 1982-09-18 | 1983-03-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-03-19 | 1986-09-18 | 1987-03-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-03-19 | 1990-09-18 | 1991-03-20 | $7700.00 | Window Closed / Lapsed |