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US4880469A
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US
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Process for the preparation of a shapeable solution of cellulose in the presence of a tertiary amine oxide and an additive
Assignee: CENTRE DE RECHERCHE SCIENTIFIQUE
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Filing: 1988-06-27
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Granted: 1989-11-14
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Expires: 2008-06-27
Abstract
Abstract The invention relates to solutions of cellulose destined to be extruded or spun, containing a tertiary amine oxide as solvent for the cellulose and in particular the N-oxide of N-methylmorpholine. It consists of using ammonium chloride or calcium chloride as additive in the preparation of these solutions.
Inventors
- 👤 Henri D. Chanzy
- 👤 Michel Paillet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 18:00
CPC Classifications
C; C08; C08B; C08B1/00; C08B1/003; D; D01; D01F; D01F2/00
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
50 words
Process for the preparation of a cellulose solution destined to be extruded or spun, of the type in which is used as solvent for the cellulose a tertiary amine oxide characterized in that ammonium chloride or calcium chloride is added to the mixture of the tertiary amine oxide and cellulose.
Claim 2
Dependent Claim
50 words
Process for the preparation of a cellulose solution destined to be extruded or spun, of the type in which is used as solvent for the cellulose a tertiary amine oxide characterized in that ammonium chloride or calcium chloride is added to the mixture of the tertiary amine oxide and cellulose.
Claim 3
Dependent Claim
35 words
Process according to claim 1, characterized in that for a cellulose having a degree of polymerization of the order of 5000, the amount of ammonium chloride is greater than 1.5 times the amount of cellulose.
Claim 4
Dependent Claim
47 words
Process according to claim 1, characterized in that for a cellulose having a degree of polymerization of the order of 5000, the amount of calcium chloride is equal to or greater than 0.5 times the amount of cellulose, and preferably is equal to the amount of cellulose.
Claim 5
Dependent Claim
36 words
Process according to claim 1, characterized in that for a cellulose having a degree of polymerization of the order of 600, the amount of ammonium chloride varies between 0.10 and 2.5 times the amount of cellulose.
Claim 6
Dependent Claim
38 words
Process for spinning a cellulose solution in a tertiary amine oxide, characterized in that the cellulose concentration of the solution lies between 2 and 10% and the ammonium chloride or calcium chloride concentration varies between 12 and 2%.
Claim 7
Dependent Claim
38 words
Process for spinning a cellulose solution in a tertiary amine oxide, characterized in that the cellulose concentration of the solution lies between 2 and 10% and the ammonium chloride or calcium chloride concentration varies between 12 and 2%.
References Cited (Backward Citations)
BE868737A
Cited
US4324593A
Cited
US4302252A
Cited
DD158656A1
Cited
DD218104A1
Cited
FR2578865A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-11-13 | 1993-05-15 | 1993-11-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-11-13 | 1997-05-15 | 1997-11-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-11-13 | 2001-05-15 | 2001-11-14 | $7700.00 | Window Closed / Lapsed |