US4086418A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing a regenerated hollow cellulosic fiber
Assignee: Rayonier Inc
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Filing: 1976-02-27
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Granted: 1978-04-25
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Expires: 1996-02-27
Abstract
Abstract Hollow 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 n-octanol where the solvent is a dialkylacylamide and n-hexanol where the solvent is dimethylsulfoxide. The fibers are hollow 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
2026-10-25 22:08
CPC Classifications
B; B01; B01D; B01D71/00; B01D71/06; B01D71/08; B01D71/10; B01D69/00; B01D69/08; C; C08; C08B; C08B16/00; C08B5/00
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
77 words
A process for producing a regenerated hollow 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 contacting the cellulosic solution with a regenerant, said regenerant being n-octanol where the solvent is a dialkylacylamide and n-hexanol where the solvent is dimethylsulfoxide.
Claim 2
Dependent Claim
77 words
A process for producing a regenerated hollow 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 contacting the cellulosic solution with a regenerant, said regenerant being n-octanol where the solvent is a dialkylacylamide and n-hexanol where the solvent is dimethylsulfoxide.
Claim 3
Dependent Claim
17 words
The process of claim 1 in which nitrosation and dissolution occurs at a temperature below 20° C.
Claim 4
Dependent Claim
16 words
The process of claim 1 in which the solvent is dimethylsulfoxide and the regenerant is n-hexanol.
Claim 5
Dependent Claim
34 words
The process of claim 3 in which the nitrosating agent is premixed with the solvent, the temperature lowered to below 20° the cellulose added and the temperature maintained at less than 20° during dissolution.
Claim 6
Dependent Claim
17 words
The process of claim 1 in which the solvent is a dialkylacylamide and the regenerant is n-octanol.
Claim 7
Dependent Claim
11 words
The process of claim 5 in which the solvent is dimethylformamide.
Claim 8
Dependent Claim
29 words
The process of claim 5 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 9
Dependent Claim
33 words
The process of claim 5 in which a salt of high solubility in the solvent is added to the regenerant to control the size of the lumen and fiber wall of the fiber.
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) | 1981-04-24 | 1981-10-24 | 1982-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-04-24 | 1985-10-24 | 1986-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-04-24 | 1989-10-24 | 1990-04-25 | $7700.00 | Window Closed / Lapsed |