Patent US4076933A successfully refreshed from Google Patents.
US4076933A
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Process for producing a regenerated shaped cellulosic fiber
Assignee: Rayonier Inc
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Filing: 1976-02-27
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Granted: 1978-02-28
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Expires: 1996-02-27
Abstract
Abstract Shaped cellulosic fibers are produced by nitrosating and dissolving a cellulosic material in an aprotic solvent selected from the group consisting of a dialkylacylamide and dimethylsulfoxide and regenerating the dissolved cellulose by contacting the cellulose solution with a regenerant. The regenerant is butanol, pentanol or benzyl alcohol where the solvent is a dialkylacylamide and propanol, butanol or benzyl alcohol where the solvent is dimethylsulfoxide. The fibers have a generally crenulated shape as regenerated and require no special spinnerette designs nor special spinning conditions.
Inventors
- 👤 Albin Frank Turbak
- 👤 Richard Benjamin Hammer
- 👤 Norman A. Portnoy
- 👤 Arthur C. West
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 03:04
CPC Classifications
C; C08; C08B; C08B5/00; C08B16/00; D; D01; D01F; D01F2/00; D01F2/24; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2973
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
115 words
A process for producing a regenerated shaped cellulosic fiber comprising nitrosating cellulose with a nitrosating agent selected from the group consisting of an oxide of nitrogen and nitrosyl chloride and dissolving the cellulose in an aprotic solvent selected from the group consisting of a dialkylacylamide and dimethylsulfoxide and regenerating the dissolved cellulose by spinning the cellulosic solution into a regenerant, said regenerant being selected from the group consisting of butanol, pentanol and benzyl alcohol, where the solvent is a dialkylacylamide and from the group consisting of propanol, butanol and benzyl alcohol where the solvent is dimethylsulfoxide, said regenerated fiber being trilobal or quadrilobal in cross-sectional shape as a result of the use of said regenerants.
Claim 2
Dependent Claim
115 words
A process for producing a regenerated shaped cellulosic fiber comprising nitrosating cellulose with a nitrosating agent selected from the group consisting of an oxide of nitrogen and nitrosyl chloride and dissolving the cellulose in an aprotic solvent selected from the group consisting of a dialkylacylamide and dimethylsulfoxide and regenerating the dissolved cellulose by spinning the cellulosic solution into a regenerant, said regenerant being selected from the group consisting of butanol, pentanol and benzyl alcohol, where the solvent is a dialkylacylamide and from the group consisting of propanol, butanol and benzyl alcohol where the solvent is dimethylsulfoxide, said regenerated fiber being trilobal or quadrilobal in cross-sectional shape as a result of the use of said regenerants.
Claim 3
Dependent Claim
27 words
The process of claim 1 in which the solvent is a dialkylacylamide and the regenerant is selected from the group consisting of butanol, pentanol and benzyl alcohol.
Claim 4
Dependent Claim
12 words
The process of claim 2 in which the pentanol regenerant is 2-methyl-butanol-4.
Claim 5
Dependent Claim
12 words
The process of claim 2 in which the regenerant is benzyl alcohol.
Claim 6
Dependent Claim
11 words
The process of claim 2 in which the solvent is dimethylformamide.
Claim 7
Dependent Claim
29 words
The process of claim 2 in which a base is added to the regenerant which is soluble in the regenerant and reactive with nitric acid introduced therein during regeneration.
Claim 8
Dependent Claim
26 words
The process of claim 1 in which the solvent is dimethylsulfoxide and the regenerant is selected from the group consisting of propanol, butanol and benzyl alcohol.
Claim 9
Dependent Claim
11 words
The process of claim 7 in which the regenerant is isopropanol.
Claim 10
Dependent Claim
11 words
The process of claim 7 in which the regenerant is butanol.
Claim 11
Dependent Claim
12 words
The process of claim 7 in which the regenerant is benzyl alcohol.
Claim 12
Dependent Claim
36 words
The process of claim 7 in which the nitrosating agent is premixed with the solvent, the temperature lowered to below 20° C, the cellulose added and the temperature maintained at less than 20° C during dissolution.
Claim 13
Dependent Claim
17 words
The process of claim 1 in which nitrosation and dissolution occurs at a temperature below 20° C.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-02-27 | 1981-08-29 | 1982-02-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-27 | 1985-08-29 | 1986-02-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-27 | 1989-08-29 | 1990-02-28 | $7700.00 | Window Closed / Lapsed |