EP1763596B1 - Method for the production of molded cellulose bodies - Google Patents

Description

The invention relates to a process for the production of moldings from cellulose with "ionic liquids", in particular 1,3-Dialkylimidazoliumhalogeniden, as a solvent, in which one dissolves the cellulose, the solution into fibers or films / membranes deformed, the cellulose by precipitation in regenerated aqueous solutions, the solvent is separated by washing and the moldings dried.

For deforming cellulose - as a non-meltable polymer - into filaments, staple fibers or films / membranes under technical conditions, three different solution spinning processes have been developed to technical maturity, namely the spinning of stable derivatives, eg cellulose 2,5-acetate, dissolved in acetone without regeneration ( Acetate Process - Ullmann's Encyclopedia Weinheim: VCH Publishing Company 1986 Vol. A5 p. 438-448 ), the spinning of semi-stable derivatives, eg cellulose xanthate, dissolved in sodium hydroxide solution with regeneration ( Götze K. "Man-made fibers by the viscose process" Berlin / Heidelberg / New York: Springer Verlag 1967 ) and the spinning of solutions of cellulose and amine oxide hydrates and regeneration by precipitation of the cellulose in aqueous amine oxide solutions Lyocell Process - Woodings C. "Regenerated Cellulose Fibers" Woodhead Publishing LTD Cambridge 2001 ; DE-A 29 13 589 and 28 48 471 . US-A 4,246,221 ].

It is also known, cellulose in "chelate" forming metal complexes, for example in copper tetramine hydroxide (Cuoxam), copper-ethylenediamine (Cuen), nickel tris (2-aminoethyl) amine (nitrene), zinc diethyltriamine; Dimethyl acetamide / lithium chloride to be dissolved Klüfers P. "Which metals form complexes with cellulose dianions" Lecture DFG / Bad Herrenalb 16.03.1999 ]. Apart from the copper tetramine hydroxide for spinning "copper silk", these solvents have probably a broad analytical interest but have not found any technical application so far.

Although ionic liquids have been known since 1914, they have only recently gained in importance as solvents or reaction media for many syntheses. Of particular interest are compounds with a positive nitrogen atom such as the ammonium; Pyridinium and imidazolium cation [ Schilling G. "Ionic Liquids" GIT Laboratory Journal 2004 (4) 372 - 373 ].

From the WO 03/029329 and the US-A 2003/0157351 It is known that certain ionic liquids, predominantly consisting of cyclic nitrogen cations and halogen anions, dissolve cellulose in the absence of water and at elevated temperature, and this precipitates again on addition of water. In the preparation of the cellulose solution, dry cellulose is dissolved in largely anhydrous ionic liquids while supplying energy, for example by heating with microwaves. No statements are made about the properties of the starting and regenerated cellulose, the cellulose solution and the possible conditions of deformation of the cellulose solution.

For a use of ionic liquids as a solvent for the deformation of the cellulose to filaments, staple fibers and films / membranes speaks a possible higher thermal stability compared to Aminoxidhydraten and a much better environmental performance compared to the viscose, acetate and copper process. As solvents, the ionic liquids should allow working in the closed solvent circuit.

Object of the present invention is to provide a method by which one bleaches at high process safety and environmental friendliness in a simple manner, cellulose (pulp, Elementarchlorfrei ECF or total chlorine-free TCF) while substantially preserving the molecular parameters to filaments, staple fibers and films / membranes deformed. With this method, shaped bodies of cellulose with new or improved properties can be produced.

1. a) Cellulose oder eine Cellulosemischung in Wasser unter Scherung bis zur Einzelfaser dispergiert, abpresst, und die pressfeuchte Cellulose bzw. Cellulosemischung,
2. b) in der ionischen Flüssigkeit, unter Zusatz basischer Substanzen und gegebenenfalls weiterer Stabilisatoren dispergiert, unter Scherung, steigender Temperatur und abnehmendem Druck (von etwa 800 bis 850 mbar auf etwa 10 bis 30 mbar) das Wasser entfernt und die Dispersion in eine homogene Lösung überführt,
3. c) die Lösung über (eine) temperierbare Rohrleitung(en) und eine Druckausgleichsvorrichtung mindestens einem Spinnpaket zuführt,
4. d) die Lösung im Spinnpaket ein Filter, eine vorzugsweise als Wärmetauscher ausgebildete Verteilerplatte und die Spinnkapillare(n) bzw. den Schlitz der Spinndüse(n) passiert,
5. e) die zu Kapillaren bzw. zur Folie verformten Lösungsstrahlen unter Verzug durch einen klimatisierten Spalt führt,
6. f) die orientierten Lösungsstrahlen durch Behandeln mit einer temperierten Lösung, die mit der ionischen Flüssigkeit mischbar ist, für die Cellulose aber ein Fällungsmittel darstellt, ausfällt, am Ende der Fällbadstrecke durch Ab - oder Umlenken vom Fällbad trennt und
7. g) den Formkörper als Filamentgarn, Faserkabel bzw. Folie/Membran abzieht, einer ein- bzw. mehrstufigen Fällmittelwäsche unterwirft, gegebenenfalls aviviert und trocknet oder zu Stapelfasern schneidet, aviviert und trocknet.

The object is achieved with a method for the production of shaped articles from cellulose by dissolving them in an ionic liquid, shaping the viscous solution to the molding and regenerating the cellulose, characterized in that

1. a) cellulose or a cellulose mixture is dispersed in water under shearing down to the individual fiber, pressed, and the cellulose or cellulosic mixture moist with moisture,
2. b) dispersed in the ionic liquid, with the addition of basic substances and optionally further stabilizers, under shear, increasing temperature and decreasing pressure (from about 800 to 850 mbar to about 10 to 30 mbar) the water is removed and the dispersion is converted into a homogeneous solution .
3. c) supplying the solution via (a) temperature-controllable pipeline (s) and a pressure compensation device to at least one spin pack,
4. d) the solution in the spin pack passes through a filter, a distributor plate, preferably designed as a heat exchanger, and the spinning capillary (s) or the slot of the spinneret (s),
5. e) the solution jets deformed into capillaries or to the foil leads through an air-conditioned gap,
6. f) the solution solution jets by treatment with a tempered solution, which is miscible with the ionic liquid, but for the cellulose is a precipitant precipitates, at the end of Fällbadstrecke by off or diverting from the precipitating bath separates and
7. g) stripping the shaped body as filament yarn, fiber cable or film / membrane, subjecting it to a single-stage or multistage precipitant wash, optionally scavenging and drying or cutting into staple fibers, scavenging and drying.

Preferably, the spinning solution reaches the spinning temperature only when passing through the distribution plate designed as a heat exchanger.

In a preferred embodiment of the process according to the invention, the spinning solution is divided into spinning capillaries of 0.4 to 5 mm overall length (I), with a cylindrical part (L = 0.5 to 3D), a conical part (I-L) and an exit diameter ( D) of 0.05 to 0.25 mm with a circular arrangement of the spinning capillaries for Filamentgame and rectangular arrangement of the spinning capillaries for staple fibers deformed.

The deformation of the spinning solution into a flat film is expediently carried out with a slot die with a gap width of 0.1 to 2.0 mm thickness. For the production of blown film ring slit nozzles are suitable with a gap width of about 0.1 to 1.5 mm.

The dispersion and dissolution of dry cellulose, without upstream consuming grinding processes, in anhydrous ionic liquids, eg. As in 1-butyl-3-methyl-imidazolium leads to no "nodule-free" suspension and even after very long dissolution times to a homogeneous solution that meets the requirements of a spinning process. Finely ground cellulose is very voluminous, not free-flowing and tends to deflagrate in the presence of air. Furthermore, it has been found that the dissolution of the cellulose carried out in this manner is associated with a significant degradation of the molecular weight. If the cuoxam-DP of a spruce sulphite pulp was found to be undissolved under microwave heating 550, a cuvoxam-DP of 172 was found for the solution-regenerated cellulose. Spinning such solutions into fibers is not possible.

In the process according to the invention, pulps of wood or cellulosic fibers of annual plants, in particular cotton linters, produced by the sulphite, sulphate-norhydrolysis sulphate or organosolv process with elemental chlorine-free (ECF) or totally chlorine-free (TCF) bleach can be used. Preference is given to using mixtures of celluloses having an average molar mass (Cuoxam DP 400 to 800) with high molecular weight celluloses (Cuoxam DP 800 to 3,000) or low molecular weight celluloses (Cuoxam DP 20 to 400). Preferred ionic liquids are melts of 1,3-dialkylimidazolium halides. For stabilization before and / or during the dissolution of the cellulose, basic substances having a low vapor pressure may be added to the ionic liquid in an amount which causes a pH of 8 or more in the suspension containing cellulose and aqueous ionic liquid. The basic compound having a low vapor pressure is particularly preferably an alkali hydroxide such as KOH or NaOH.

und Relaxationszeit ${\lambda }_m^{\vartheta }$

[siehe Michels Ch. Das Papier 52 (1998) 1 S. 3-8 ] charakterisiert werden. In der Praxis liegen bei diesen Lösungen Relaxationszeitspektren [H = f(λ)] vor, da die Cellulose eine Molmassenverteilung aufweist. ${\lambda }_m^{\vartheta }$

ist dann die Relaxationszeit beim Häufigkeitsmaximum im gewichteten Relaxationszeitspektrum [H*λ = f(λ)]. Im Unterschied zu den Cellulose/Aminoxidhydrat-Lösungen, erfolgt die Solvatation der Cellulose im 1-Butyl-3-methyl-imidazoliumchlorid bzw. 1-Ethyl-3-methyl-imidazoliumchlorid deutlich langsamer und das Erreichen der minimalen Nullscherviskosität (vollständige Solvatation) ist wesentlich stärker von der Lösetemperatur und Lösezeit abhängig.In the method according to the invention, the pulp is whipped up to a single fiber under high shear in water. After pressing swollen cellulose is present with about 50% by mass of water. For example, in aqueous 1-butyl-3-methylimidazolium chloride, which contains at the same time as much alkali hydroxide as achieves a pH of> 8, the cellulose which is moist with respect to the press can easily be converted into a homogeneous suspension which is distilled off under shear, temperature increase and pressure reduction of water into a homogeneous spinning solution. Under these conditions, the dissolution time is only a fraction of that needed to dissolve dry cellulose in anhydrous 1-butyl-3-methyl-imidazolium chloride. The reduction in molecular weight is less than 10%. The spinning solution quality can be determined analogously to the lyocell process by determining the particle content c _ppm and the particle distribution related to the class width [q3x = f (x)] by means of laser diffraction [see Kosan B. Michels Ch. Chemical Fibers International 48 (1999) 4 pp. 50-54 ], as well as zero shear viscosity ${\eta }_0^{\theta }$

and relaxation time ${\lambda }_m^{\theta }$

[please refer Michels Ch. Paper 52 (1998) 1 pp. 3-8 ] are characterized. In practice, relaxation time spectra [ H = f ( λ )] are present in these solutions since the cellulose has a molecular weight distribution. ${\lambda }_m^{\theta }$

is then the relaxation time at the frequency maximum in the weighted relaxation time spectrum [ H * λ = f ( λ )]. In contrast to the cellulose / amine oxide hydrate solutions, the solvation of the cellulose in 1-butyl-3-methylimidazolium chloride or 1-ethyl-3-methylimidazolium chloride is significantly slower and the achievement of the minimum zero shear viscosity (complete solvation) is essential more dependent on the dissolution temperature and dissolution time.

gegeben. Ihre Kenntnis ist für das Verformen hochelastischer Lösungen im Spinndüsenkanal und Spalt, von wesentlicher Bedeutung.The temperature function of zero shear viscosity and relaxation time is given by the relationship (1) $$\ln \eta \left(\lambda \right)=\ln K_{\eta \left(\lambda \right)}+\frac{e_A}{R\cdot T}$$

given. Their knowledge is essential for the deformation of highly elastic solutions in the spinneret channel and gap.

The cellulose concentration and the molecular weight of the cellulose or cellulose mixture are suitably chosen so that at 85 ° C, a zero shear viscosity of the spinning solution of 1,000 to 100,000 Pa s, preferably from 10,000 to 80,000 Pa s, adjusts.

For a high stability of the molecular weight over a long time at elevated temperature, in addition to the addition of bases, such an antioxidant has been proven. These are, in particular, organic compounds having at least one conjugated double bond and two hydroxyl or amino groups, such as hydroquinone, p- phenylenediamine, gallic acid esters, tannins, and the like. As can be seen from DTA / DSC and reaction calorimetric measurements, the thermal stability of the spinning solutions according to the invention is significantly higher compared to stabilized lyocell spinning solutions. While in stabilized cellulose / Aminoxidhydratlösungen above 130 ° C, the risk of explosive decomposition, the 1-butyl-3-methyl-imidazolium is stable to at least 250 ° C and the stabilized spinning solution, the cellulose begins to decompose above 213 ° C.

bei Spinntemperatur relaxieren lässt, durch Spinndüsen zu Filamenten bzw. Folien verformt und unter Verzug durch einen Spalt zum Fällbad führt. Zwischen Wärmetauscherausgang und Spinnkapillaren sollte ein Volumen V in cm³ bleiben, welches mindestens gleich oder größer dem Produkt aus Volumenstrom ν̇_L in cm³/s und Relaxationszeit λ_m in s bei Spinntemperatur ist. $$V\ge {\dot{v}}_L\cdot {\lambda }_m$$

The deformation of the solution into filaments, staple fibers and films / membranes takes place in a modified dry-wet extrusion process such that the solution via a temperature-adjustable pipe and pressure compensation device the spinning package with dissolving temperature θ _L feeds, here by a Sicherheitssspinnfilter presses, in a temperature-controlled Heat exchanger sets the required spinning temperature θ _Sp , the solution according to their relaxation time ${\lambda }_m^{\theta }$

relax at spinning temperature, through spinnerets to filaments or foils deformed and leads with delay through a gap to the precipitation bath. Between the heat exchanger outlet and spin capillaries, a volume V should remain in cm ³ , which is at least equal to or greater than the product of volume flow ν̇ _L in cm ³ / s and relaxation time λ _m in s at spinning temperature. $$V\ge {\dot{v}}_L\cdot {\lambda }_m$$

In the gap, which consists of an air-conditioned zone, the yarn sheet is applied perpendicular to the thread running direction and sheet-like with conditioned air of preferably 15 to 25 ° C and 20 to 80% relative humidity.

The thread formation can be represented as a two-stage process. In the spinning capillary, a tapering of the solution jet from the inlet A _E to the outlet cross section A _{A of} the spinning capillary occurs predominantly under the influence of the shearing stress τ _D at constant temperature, ie the draft in the nozzle SV _D follows $$S{V}_D=\frac{A_e}{A_A}={\left(\frac{D_{\mathrm{<figure-callout\; id="2"\; label="e\; D\; A"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">e\; </figure-callout>}}}{D_A}\right)}^2$$

D _E and D _A correspond to the entry or exit diameter of the spinning capillary. In the gap of length a under the influence of the axial expansion stress σ _a with decreasing temperature, a further taper of the solution jet in the ratio of withdrawal ν _a and injection speed ν _s , the spinning distortion SV _a . $$S{V}_a=\frac{v_a}{v_s}={\left(\frac{D_A}{D_{\mathrm{<figure-callout\; id="2"\; label="K"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">K</figure-callout>}}}\right)}^2$$

verbunden. Darin bedeuten O_A die Oberfläche des Fadens am Spinnkapillarenaus- und O_K die Oberfläche des Fadens am Fällbadeintritt. Die Oberflächenvergrößerung pro Zeiteinheit ΔȮ_a im Spalt der Länge a ergibt sich dann mit $${\dot{O}}_A=D_A\cdot \pi \cdot v_s\mathrm{und}{\dot{O}}_K=D_K\cdot \pi \cdot v_a$$

zu $$\mathrm{\Delta }{\dot{O}}_a={\dot{O}}_K-{\dot{O}}_A=D_A\cdot \pi \cdot v_s\left(\sqrt{{\mathit{SV}}_a}-1\right)$$

und mit $$v_s=3,6\cdot {10}^{-2}\frac{T_{10}\cdot v_a}{D_A^2\cdot \pi \cdot {\rho }_L\cdot c_{\mathit{Cell}\mathrm{.}}}$$

folgt $$\mathrm{\Delta }{\dot{O}}_a=3,6\cdot {10}^{-2}\frac{T_{10}\cdot v_a}{D_A\cdot {\rho }_L\cdot c_{\mathit{Cell}\mathrm{.}}}\left(\sqrt{{\mathit{SV}}_a}-1\right)\left(\frac{{\mathit{cm}}^2}{\min }\right)$$

für die Oberflächenzunahme einer Kapillare pro Zeiteinheit. Darin bedeuten T ₁₀ die Faserfeinheit in dtex, ρ_L die Dichte der Spinnlösung in g/cm³ und c_Cell. die Cellulosekonzentration in Masse-%. Es ist leicht einzusehen, dass die Neubildung von Oberflächen während der Fadenverfestigung im Spalt mit Störungen im Fasermantel verbunden sein sollte und das Fibrillierverhalten der Fasern negativ beeinflusst. Hinzu kommt, dass die Lösungsstrahlen in hohem Maße hygroskopisch sind, Wasser aus der klimatisierten Umgebung aufnehmen und in den Randzonen eine partielle Fällung der Cellulose stattfindet.D _K corresponds to the capillary diameter at the transition gap / precipitation bath. The delay of the solution jet in the gap is simultaneous with an increase of the thread surface according to (5) $$O_K=\sqrt{{\mathit{SV}}_a}\cdot O_A$$

connected. Therein, O _{A is} the surface of the thread at the spinning capillary outlet and O _{K is} the surface of the thread at the precipitation bath inlet. The surface enlargement per unit time ΔȮ _a in the gap of length a then results with $${\dot{O}}_A=D_A\cdot \pi \cdot v_s\mathrm{and}{\dot{O}}_K=D_K\cdot \pi \cdot v_a$$

to $$\mathrm{\Delta }{\dot{O}}_a={\dot{O}}_K-{\dot{O}}_A=D_A\cdot \pi \cdot v_s\left(\sqrt{{\mathit{SV}}_a}-1\right)$$

and with $$v_s=3.6\cdot {10}^{-2}\frac{{\mathrm{<figure-callout\; id="10"\; label="T"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">T</figure-callout>}}_{10}\cdot v_a}{{\mathrm{<figure-callout\; id="2"\; label="D\; A"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">D\; </figure-callout>}}_A^{}\cdot \pi \cdot {\rho }_L\cdot c_{\mathit{Cell}\mathrm{,}}}$$

follows $$\mathrm{\Delta }{\dot{O}}_a=3.6\cdot {10}^{-2}\frac{{\mathrm{<figure-callout\; id="10"\; label="T"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">T</figure-callout>}}_{10}\cdot v_a}{D_A\cdot {\rho }_L\cdot c_{\mathit{Cell}\mathrm{,}}}\left(\sqrt{{\mathit{SV}}_a}-1\right)\left(\frac{{\mathit{<figure-callout\; id="2"\; label="cm"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">cm</figure-callout>}}^2}{\min }\right)$$

for the surface increase of a capillary per unit time. Where T _{10 is} the fiber denier in dtex, ρ _{L is} the density of the spinning solution in g / cm ³ and c _Cell. the cellulose concentration in mass%. It is easy to see that the formation of new surfaces during the thread consolidation in the gap should be associated with disruptions in the fiber cladding and adversely affect the fibrillation behavior of the fibers. In addition, the solution jets are highly hygroscopic, absorb water from the air-conditioned environment and take place in the peripheral areas of a partial precipitation of the cellulose.

In the method according to the invention, it has been shown that very good fiber properties are achieved when the surface increase Δ̇ Ȯ _{a reaches} values of <200 cm ² / min, in particular <20 cm ² / min.

Another important factor is the normalized to the gap a = 1 surface increase. $${\tilde{v}}_{\mathit{at}}=10\frac{\mathrm{\Delta }{\dot{O}}_a}{\alpha }\left[\mathit{mm}/\min \right]$$

With Δ Ȯ _a in cm ² / min and a in cm. It is a measure of the rate of surface change and should be as small as possible. Good fiber properties are obtained for values ν _at <500 mm / min, in particular for ν _at <50 mm / min.

The air conditioning of the gap, preferably by air with a certain temperature and moisture, in addition to a cooling and stabilizing effect of the yarn path, a partial precipitation of the cellulose, preferably in the edge zones of the filaments result. This increases the spinning safety, especially with high capillary densities, promotes the formation of a core / shell structure and improves the fiber properties. When passing the air-conditioned draft zone, the group of threads is preferably additionally subjected to a likewise conditioned gas stream.

In the process of the present invention, the oriented solution jets are passed to regenerate the cellulose through an aqueous precipitation bath containing up to 50% by weight, preferably up to 25% by weight, of the ionic liquid used to dissolve.

It has furthermore been found that, when using, for example, 1,3-dialkylimidazolium halides as solvent, the slightly brownish precipitation bath is decolorized by treatment with alkaline hydrogen peroxide at 60 to 80 ° C. and the cations introduced through the pulp or other auxiliary products via cation exchangers can remove. The precipitation bath thus purified can be recirculated as a solvent after distillative concentration.

Figur 1:

eine graphische Darstellung der Partikelverteilung einer typischen Cellulose/1-Butyl-3-methyl-imidazoliumchlorid-Spinnlösung mit 11,5 Masse-% Baumwoll-Linterszellstoff;

Figur 2:

eine graphische Darstellung des gewichteten Relaxationszeitspektrums einer Spinnlösung mit 12,5 Masse-% Eukalyptusvorhydrolysesulfatzellstoff bei 85°C;

Figur 3:

eine graphische Darstellung der Temperaturfunktion von Nullscherviskosität und Relaxationszeit für die Spinnlösung gemäß Figur 2;

Figur 4:

die durch DSC-Analyse ermittelte Enthalpie als Funktion der Temperatur für 1-Butyl-3-methyl-imidazolium-chlorid und für eine Spinnlösung mit 12 Masse-% Fichtensulfitzellstoff und 1-Butyl-3-methyl-imidazoliumchlorid als Lösungsmittel;

Figur 5:

die schematische Darstellung einer Vorrichtung zur Durchführung des Verfahrens zur Herstellung von Filamentgarnen und Spinnfasern;

Figur 6:

die schematische Darstellung einer bevorzugten Vorrichtung zur Herstellung von Spinnfasern und Folien;

Figur 7:

eine schematische Darstellung der als Wärmetauscher ausgebildeten Verteilerplatte.

The method according to the invention and the device used therein will now be explained with reference to the drawings and by way of examples. Show it

FIG. 1:

a plot of particle distribution of a typical cellulose / 1-butyl-3-methyl-imidazolium chloride spinning solution with 11.5% by weight of cotton linters pulp;

FIG. 2:

a plot of the weighted relaxation time spectrum of a spinning solution containing 12.5% by weight eucalyptus prehydrolysis sulfate pulp at 85 ° C;

FIG. 3:

a graphical representation of the temperature function of zero shear viscosity and relaxation time for the spinning solution according to FIG. 2 ;

FIG. 4:

the enthalpy determined by DSC analysis as a function of temperature for 1-butyl-3-methylimidazolium chloride and for a spinning solution containing 12% by weight of spruce sulphite pulp and 1-butyl-3-methylimidazolium chloride as solvent;

FIG. 5:

the schematic representation of an apparatus for carrying out the method for producing filament yarns and staple fibers;

FIG. 6:

the schematic representation of a preferred apparatus for producing staple fibers and films;

FIG. 7:

a schematic representation of the formed as a heat exchanger distributor plate.

FIG. 1 shows the density distribution determined by laser diffraction q3 * (x) over the particle size in μm for a spinning solution of 11.5 mass% cotton linter pulp (Cuoxam DP 650) stabilized with 0.22 mass% NaOH (based on the solvent) and 88.5% by weight of 1-butyl-3-methyl-imidazolium chloride having a zero shear viscosity of 31650 Pas and a relaxation time of 5.3 seconds at 85 ° C. The particle content of 20 ppm is divided into 81% <12 μm and 19% <40 μm equivalent particle diameter. This corresponds to a solution quality that is suitable for spinning fibers.

FIG. 2 shows the weighted relaxation time spectrum (H * λ) = f (λ) for a spinning solution of 12.5% by mass of eucalyptus stabilized with 0.22% by mass of NaOH and 0.04% by mass of gallic acid propyl ester (based on the solvent) Prehydrolysis sulphate pulp (Cuoxam DP 569) and 87.5% by weight of 1-butyl-3-methylimidazolium chloride having a zero-shear viscosity of 27010 Pas and a relaxation time of 9.5 s at 85 ° C. The particle content was 22 ppm with a share of 40% <12 microns and 60% <40 microns.

FIG. 3 contains the temperature function of zero shear viscosity and relaxation time (at the frequency maximum) in the temperature range 70 -130 ° C for the spinning solution in FIG. 2 , The comparison of the spinning solutions in the FIGS. 1 to 3 illustrates the influence of pulp yield, molecular weight (Cuoxam DP), cellulose concentration, stabilization and temperature on zero shear viscosity, relaxation time and solution state.

FIG. 4 shows the results for the thermal analysis of the solvent 1-butyl-3-methylimidazolium chloride and a stabilized spinning solution of 12% by weight of eucalyptus Vorhydrolysesulfatzellstoff and 88% by weight of 1-butyl-3-methyl-imidazoliumchlorid. While the solvent has no changes in addition to the endothermic melting peak up to 250 ° C, the curve of the spinning solution next to the endothermic melting peak, an exothermic peak starting at 213 ° C. Obviously, here begins the thermal degradation of cellulose.

FIG. 5 shows a spinning device for carrying out the method according to the invention. It consists of a temperature-controlled pipe (1), pressure compensation device (2), spin pack (3), draft zone (9), precipitation bath (11) and Abzugsgalette (18). The spin pack (3) comprises a distribution plate designed as a heat exchanger (5) with a solution filter (4), an inflow chamber (6) and at least one spinneret (7). Between spin pack (3) and precipitation bath (11) is the conditioned draft zone (9) with gas supply / distribution (10) whose length is adjustable by vertical movement of the precipitation bath (11). The Fällbadbehälter (11) comprises the inflow chamber (12) for forming a laminar Fällbadströmung, the overflow (13) by a existing existing ceramic thread guide bottom opening (14), the collecting trough (15), Fällbadpumpe (16) and thermostat (17 ). About the thread guide in the bottom opening (14) and the Abzugsgalette (18) separates the filament bundle (19) from the precipitation bath (11) by peeling at the angle ß, which is preferably less than 70 °.

FIG. 6 shows a spinning device, which preferably serves for spinning of staple fibers and films. The structure up to the spinneret (7) largely corresponds to the FIG. 5 , The spinneret (7) here forms a rectangle and contains in-line spinning capillaries or a slot for spinning films. The conditioned draft zone (9) and the gas supply / distribution (10) are adapted to this rectangular shape. The length of the draft zone (9) is adjusted by vertical displacement of precipitation bath (11). As indicated by the dotted line, the draft zone (9) is largely closed. The gas supply / distribution (10) opposite openings are arranged for discharging the conditioned air blowing gas. The precipitation bath (11) is again formed from inflow or settling chamber (12), overflow (13), deflection roller or roller (14), collecting trough (15), pump (16) and thermostat (17). The separation of yarn sheet (19) and precipitation bath (11) by deflecting at an angle> 90 ° and deduction on the Galettenduo (18). When spinning films, a driven roller (14) takes over the deflection and further guide rollers transport to the godet pair (18).

FIG. 7 schematically shows the structure of the heat exchanger (5) formed distribution plate with solution filter (4), seals (8) and heaters (H). The spinning solution with the temperature T1 ( θ _L ) passes through the solution filter (4), flows through a plurality of holes (R) with simultaneous heating to the spinning temperature T2 ( θ _Sp ) and passes at this temperature upstream chamber (6) and nozzle (7 ). The heat exchanger (5) is preferably made of nickel-plated or chromium-plated aluminum, copper or brass. In addition, it expediently comprises a well sealed off by seals (8) for receiving the filter pack (4), a separate heater (H) and flow channels (R).

Examples 1 to 7

20 h Pas DP_Lösg. 0 h DP_Lösg. 20 h

1 ---- ---- 550 1040 400 290 53 2 0,05 ---- 550 9921 488 468 85 3 0,22 ---- 550 19800 521 490 89 4 0,40 ---- 550 19910 525 496 90 5 0,22 0,03 ²⁾ 550 27010 530 530 96 6 0,22 0,04 ³⁾ 550 26920 529 528 96 7 0,22 0,03 ⁴⁾ 550 26895 528 529 96 ¹⁾ bezogen auf BMIMCI
²⁾ Gallussäurepropylester
³⁾ p-Phenylendiamin;
⁴⁾ p-Hydrochinon A spruce sulphite pulp (Cuoxam DP 550, ECF-bleached) was beaten in water at a ratio of 1:20 in water and dewatered by pressing to 40% by mass. By dispersing 75 g of moist cellulose in 275 g of 1-butyl-3-methyl-imidazolium chloride (BMIMCI) with 20% by mass of water and stabilizer additives according to Table 1 gave 350 g of homogeneous suspension, which after entry into a vertical kneader under high shear, slowly rising temperature of 85 to 120 ° C and decreasing pressure of 850 to 20 mbar Water removal was transferred to a homogeneous solution. The release time was uniformly 60 minutes. The solution with 12% by mass of cellulose and 88% by mass of BMIMCI (refractive index 1.5228 at 50 ° C.) was tested immediately after dissolution and after spinning (equivalent to a service life of 20 hours at 85 ° C.). The results are included in Table 1. <u> Table 1 </ u> example NaOH ¹⁾ % Rod. ¹⁾ % DP _cellst. ${\eta }_0^{85°C}$

20 h pas DP _solution 0 h DP _solution 20 h

1 ---- ---- 550 1040 400 290 53 2 0.05 ---- 550 9921 488 468 85 3 0.22 ---- 550 19800 521 490 89 4 0.40 ---- 550 19910 525 496 90 5 0.22 0.03 ²⁾ 550 27010 530 530 96 6 0.22 0.04 ³⁾ 550 26920 529 528 96 7 0.22 0.03 ⁴⁾ 550 26895 528 529 96 ¹⁾ based on BMIMCI
²⁾ Gallic acid propyl ester
³⁾ p-phenylenediamine;
⁴⁾ p-hydroquinone

The addition of alkali resulted in a significant stabilization of the cellulose. Obviously, the BMIMCI cleaved traces of hydrochloric acid at higher temperature, resulting in cleavage of the cellulose's 1,4-acetal linkage. By low addition of radical scavengers as in Example 5, to 7, the thermal long-term stability of the spinning solutions could be further improved.

Example 8

375 g of eucalyptus prehydrolysis sulphate pulp (Cuoxam DP 569, TCF-bleached) were beaten in water in a jet mixer at a liquor ratio of 1:15, separated from the liquor by a centrifuge to 50% by mass, coarsely crushed and pressed moist in 3088 g of 1-butyl 3-methyl-imidazolium chloride (BMIMCI) with 15% by mass of water, which simultaneously contained 0.22% by mass of sodium hydroxide and 0.036% by mass of gallic acid propyl ester. By introducing the suspension into a vertical kneader, evaporation of 838 g of water for 60 minutes under high shear, elevated temperature (85 to 130 ° C) and vacuum (800 to 15 mbar), a homogeneous solution of 12.5 mass% of cellulose and 87.5 mass% BMIMCI with a zero shear viscosity of 32 680 Pa s, a relaxation time of 9.8 s at 85 ° C and a temperature function according to $$\ln {\mathrm{<figure-callout\; id="0"\; label="\eta "\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">\eta </figure-callout>}}_{\mathrm{0}}\mathrm{=}\mathrm{16}\mathrm{.}\mathrm{9874}\mathrm{+}\mathrm{9799}\mathrm{*}\mathrm{1}\mathrm{/}\mathrm{T}$$

The particle content of the solution was 18 ppm with a content of 65% <12 μm and 35% <40 μm.

The spinning of the solution was carried out in a test apparatus according to FIG. 5 , The required amount of spinning solution ṁ _L was supplied to the spinning package at 85 ° C. melt temperature via a temperature-controlled pipe at the same temperature by means of a spinning pump (0.10 ml / Umd.), Filtered, heated in the heat exchanger to spinning temperature θ _Sp. , In the onflow chamber with about 8 volume is reduced and forced through nozzles with 30 or with Vers. No. 7.12 60 spinning capillaries with an L / D _A ratio of 1 or with Vers. No. 5.3 of 2 and the exit diameter D _A. The solution jets passed under the delay SV _a the air-conditioned air gap of length a and were additionally blown with 25 (staple fibers) or 100l / min (filament yarn) air of 25 ° C and humidity according to table. The oriented group of threads passed under simultaneous precipitation of the cellulose, the spinning bath at a temperature of 20 ° C was separated at the withdrawal speed v _a at an angle ß = 40 ° from the precipitation bath, withdrawn via godets and fed to the aftertreatment. For the spun fiber samples the aftertreatment was carried out batchwise and without tension and in the filament yarn (Vers. No. 7.12) continuously under minimum tension (<2 cN / tex) by washing, drying with 2.5% shrinkage, finishing and tangential winding on cylindrical coils.

= 1,11 g/cm³ Tabelle 3 (Fasereigenschaften) Vers. Nr. Feinh. Dtex σ_kond. cN/tex σ_nass cN/tex δ_kond. % δ_nass % σ_schl. cN/tex M_A cN/tex Mnass cN/tex NSB¹⁾ T 7.4 1,66 49,3 40,7 12,8 12,6 22,3 963 311 55 7.10 1,70 45,9 39,3 16,7 12,6 26,3 850 299 69 5.3 1,64 43,2 35,7 11,4 10,8 23,6 734 288 33 5.9 1,57 42,2 36,2 12,2 13,2 26,3 711 241 37 5.11 1,64 37,7 33,7 12,6 13,1 28,4 641 228 64 7.1 1,70 36,7 30,5 18,1 20,4 25,9 786 160 94 7.12 1,67 44,8 41,1 7,8 8,2 ---- 1250 395 ---- ¹⁾ Die Methode zur Bestimmung der Nassscheuerbeständigkeit ist von Mieck K.P. u.a. in Melliand Textilberichte 74(1993) 945 u. Lenzinger Berichte 74(1994) 61-68 ausführlich beschrieben. The spinning conditions and the spun fiber or filament yarn properties are listed in Tables 2 and 3 below. Table 2 also shows the calculated surface increase Δ Ȯ _a and the speed ν _at which the surface increase took place. <u> Table 2 </ u> (spinning conditions) Verse no. g _L g / min u. Nozzle ²⁾ D _A μm θ _spinning. ° C A mm Humidity g / m ³ V _a m / min SV _a Δ Ȯ _a cm ² / min ν _at mm / min 7.4 1,076 130 115 25 5.4 30.0 12.3 24.9 100 7.10 1,120 110 111 30 11.7 30.5 8.6 23.7 79 5.3 1,771 90 122 18 6.2 50.1 6.0 34.3 190 5.9 1,696 70 120 18 11.5 50.0 3.8 27.6 153 5.11 1.063 70 125 19 11.4 30.0 3.6 16.4 86 7.1 1,836 70 120 40 12.8 30.0 3.5 16.4 41 7.12 10.82 ¹⁾ 110 125 40 12.5 150 8.8 116 290 ¹⁾ filament yarn 100 dtex (60); ²⁾ ${\rho }_L^{85°C}$

= 1.11 g / cm ³ Verse no. Feinh. dtex σ _cond. CN / tex σ _wet cN / tex δ _cond. % δ _wet % σ _schl. CN / tex M _A cN / tex Mnass cN / tex NSB ¹⁾ T 7.4 1.66 49.3 40.7 12.8 12.6 22.3 963 311 55 7.10 1.70 45.9 39.3 16.7 12.6 26.3 850 299 69 5.3 1.64 43.2 35.7 11.4 10.8 23.6 734 288 33 5.9 1.57 42.2 36.2 12.2 13.2 26.3 711 241 37 5.11 1.64 37.7 33.7 12.6 13.1 28.4 641 228 64 7.1 1.70 36.7 30.5 18.1 20.4 25.9 786 160 94 7.12 1.67 44.8 41.1 7.8 8.2 ---- 1250 395 ---- ¹⁾ The method for determining the wet abrasion resistance is from Mieck KP et al. In Melliand Textile Reports 74 (1993) 945 u. Lenzinger reports 74 (1994) 61-68 described in detail.

The dissolved cellulose cuoxam DP was 531 and that of the fiber was 529. The fiber properties had high levels of tensile strength and moduli in the conditioned and wet state, as well as increased wet abrasion resistance over lyocell fibers.

Example 9

A cotton linter pulp (Cuoxam DP 650) was analogously to Example 8 in a spinning solution with 11.5% by mass of cellulose, zero shear viscosity 31650 Pas at 85 ° C, relaxation time 5.3 s at 85 ° C, particle content 20 ppm, particles <12 81% and particles <40 μm transferred 19%. The spinning was carried out in an apparatus according to FIG. 5 under the following conditions: output 1.35 g / min Diameter D _A 100 μm (30 capillaries) spinning temperature 100 ° C Default SV _a 9.3 air gap 12 mm Rel. Humidity 7.5 % spinning bath 20 ° C off speed 50.2 M / min

Fibers with very high tensile strengths and moduli in the conditioned and wet state were obtained: fineness 1.27 dtex tear strength cond. 67.7 CN / tex wet 60.9 CN / tex elongation at break cond. 9.0 % Wet 8.8 % initial modulus cond. 1366 CN / tex Wet 511 CN / tex Wet scrub resistance 43 T Cuoxam DP fiber 624

Example 10

A mixture of 85% by weight Buchevorhydrolysesulfatzellstoff (Cuoxam DP 390, TCF bleached) and 15% by weight Fichtesulfitzellstoff (Cuoxam DP 780, ECF bleached) was pitched together in water to the individual fiber by means of jet mixer and separated by a belt filter press from the fleet. 1020 g of the wet cellulose with a water content of 52% by mass were mixed thoroughly in 3478 g of BMIMCI with 15% by weight of water which simultaneously contained 0.22% sodium hydroxide and 0.036% propyl gallate in a vertical kneader and under shear, elevated temperature (85 / 130 ° C) and vacuum (700/20 mbar) distilled off during 60 minutes 1044 g of water and then dissolved for 60 minutes. The resulting solution contained 14.0% by mass of cellulose with a cuoxam DP of dissolved cellulose of 465. The zero-shear viscosity at 85 ° C. was 13 100 Pas, the relaxation time 5.5 s. The particle analysis revealed a content of 28 ppm with a particle distribution of 82% <12 μm; 16% <40 μm and 2%> 40 μm. For spinning the Solution served an apparatus according to FIG. 6 , 19.1 g / min of spinning solution of 90 ° C. passed through a spinning pump into the spin pack, which was filtered through a sieve filter (mesh size 25 μm), heated to 110 ° C. in the heat exchanger and passed through a rectangular nozzle with 900 spinning capillaries (arranged on an area of 1 x 3 cm) of 75 μm exit diameter were pressed. The yarn sheet passed under a draft of 5.1 the air-conditioned gap of 2.8 cm in length and was over a width of 9 cm with 160 l / min air of 23 ° C and 70% relative humidity flowed. The surface increase on warpage was 0.128 cm ² / min + capillary, its velocity 0.46 mm / min.

After precipitating the cellulose in the spinning bath of 23 ° C and diverting the yarn sheet this reached a Galettenduo at a take-off speed of 22 m / min .. After cutting the fiber cable in stacks of 40 mm in length, washing and preparing the drying at 90 ° C to to a residual moisture of 10% by mass. For the mechanical fiber properties, the following values were obtained: fineness 1.50 dtex Tear strength cond. 44.1 CN / tex Wet tensile strength 40.0 CN / tex Elongation at break 12.1 % Elongation at break wet 12.0 % Loop tear cond. 32.2 CN / tex Module cond. 920 CN / tex Module wet 340 CN / tex NSB 130 tour

Example 11

A mixture of cotton linters pulps (80% by mass of Cuoxam DP 465 and 20% by mass of Cuoxam DP 650) were prepared analogously to Example 9. The press-moist cellulose mixture had a water content of 45% by mass. In a horizontal single-shaft mixing / kneading reactor of the type Diskotherm B (LIST AG ARISDORF Switzerland) were in the first shear zone continuously via a precision gear pump 819 g / min preheated to 90 ° C 1-ethyl-3-methyl-imidazoliumchlorid (EMIMCI) containing 10% by mass of water, 0.28% sodium hydroxide and 0, Tannin contained 04%, and metered via a belt scale and control piston pump 200 g / min crushed cellulose, mixed and heated under a vacuum of 30 mbar to 120 ° C and distilled off 172 g / min of water. The resulting in the second shear zone pale yellow homogeneous solution with 13% by mass of cellulose (zero shear viscosity 11450 Pas at 85 ° C) was cooled to 110 ° C, taken from a vertical double-skid conveyor and fed to a wide-film laboratory. This corresponded in the structure of the arrangement in FIG. 6 , Through a pressure compensation device and precision gear pump 847 g / min spinning solution were fed to the spin pack, filtered, homogenized in the heat exchanger to 110 ° C and pressed through a film die of 100 mm slit width and 1.2 mm thickness. The solution, which was deformed into a flat film, passed an air-conditioned air gap (20 ° C., 55% relative humidity) of 15 mm in length, passed into the precipitation bath (an aqueous solution containing EMIMCI), and was deflected by means of a driven roller and tightened by the roller duo at 20 m / min. After washing, drying and preparation, a conditioned film of 40 μm thickness and a basis weight of 61 g / m ^{2 was obtained} . The longitudinal tear strength of the film was 27.2 cN / tex, its elongation 16.8%.

Example 12

234 g of eucalyptus prehydrolysis sulphate pulp (Cuoxam DP 569, TCF-bleached) were beaten in water with an Ultramischer in the liquor ratio 1:25 in water, adjusted to a pH of 10 with sodium hydroxide, separated from the liquor by pressing down to 26.7% by mass , coarsely crushed and dry in 1520.5 g of 1-butyl-3-methyl-imidazolium chloride (BMIMCI) containing 22% by mass of water, 1.4 g of sodium hydroxide and 1.2 g of gallic acid propyl ester dispersed.

By introducing the suspension (2400 g) into a horizontal twin-screw kneader of the CPR 2.5 batch type (List AG Arisdorf), evaporating 980 g of water for 90 minutes under high shear (shaft speed 30/24 to 90/72 rpm), elevated melt temperature ( 85 to 145 ° C) and vacuum (800 to 10 mbar), a homogeneous concentrated solution of 16.5% by mass of cellulose and 83.5% by mass BMIMCI (molar ratio of cellulose: BMIMCI // 1: 4.67) was formed with a Zero shear viscosity of 72 560 Pas, a relaxation time of 4.8 s at 85 ° C and a temperature function according to $$\ln {\mathrm{<figure-callout\; id="0"\; label="\eta "\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">\eta </figure-callout>}}_{\mathrm{0}}\mathrm{=}-\mathrm{15}\mathrm{.}\mathrm{35831}\mathrm{+}\mathrm{9505}\mathrm{*}\mathrm{1}\mathrm{/}\mathrm{T}$$

The particle content of the solution was 33 ppm with a proportion of 61% <12 .mu.m and 39% <40 .mu.m.

Tabelle 5 (Fasereigenschaften) Vers. Nr. T₁₀ dtex σ_kond. cN/tex σ_nass cN/tex δ_kond. % δ_nass % σ_Schl. cN/tex MA cN/tex M_nass cN/tex NSB T 1 1,70 51,1 44,8 13,2 12,1 26,9 732 291 62 2 1,53 54,2 48,6 12,1 11,6 28,3 865 324 51 3 1,29 57,8 52,2 11,4 10,8 31,2 954 388 43 The spinning of the solution was carried out in a test apparatus according to FIG. 5 , The required amount of spinning solution ṁ _L was supplied to the spin pack at 95 ° C. melt temperature via a temperature-controlled pipe at the same temperature by means of a spinning pump (0.10 ml / Umd.), Filtered, heated in the heat exchanger to spinning temperature θ _Sp. , In the onflow chamber with about 8 ml volume and compressed through nozzles with 60 spinning capillaries with an L / D _A ratio of 1 and the exit diameter D _A. The solution jets passed under the delay SV _a air-conditioned air gap of length a and were additionally blown with 85 l / min air of 25 ° C and 2.5 g / m ^{3 of} water. The oriented group of threads passed under simultaneous precipitation of the cellulose, the spinning bath at a temperature of 20 ° C was separated at the withdrawal speed V _a at an angle ß = 40 ° from the precipitation bath, withdrawn via godets and fed to the discontinuous aftertreatment. Spinning conditions and fiber properties are shown in Tables 4 and 5 below. <u> Table 4 </ u> (spinning conditions) Verse no. g _L g / min u. Nozzle ¹⁾ T ₁₀ dtex D _A μm θ _spinning. ° C η _spinning. Pas a mm SVa SV _{a, D} ²⁾ V _a m / min 1 1,669 1.70 100 125 5 030 50 9.5 8.9 30.0 2 1,473 1.50 100 127 4 460 50 10.8 9.5 30.1 3 1,276 1.30 100 130 3,740 50 12.5 10.2 30.1 ¹⁾ 60 capillaries in 4 rows a 15; ²⁾ ${\mathit{SV}}_{\mathit{D}\mathit{.}\mathit{a}}\mathit{=}\sqrt{{\mathit{SV}}_{\mathit{D}}\mathit{\cdot }{\mathit{SV}}_{\mathit{a}}}$

Verse no. T ₁₀ dtex σ _cond. CN / tex σ _wet cN / tex δ _cond. % δ _wet % σ _sleep CN / tex MA cN / tex M _wet cN / tex NSB T 1 1.70 51.1 44.8 13.2 12.1 26.9 732 291 62 2 1.53 54.2 48.6 12.1 11.6 28.3 865 324 51 3 1.29 57.8 52.2 11.4 10.8 31.2 954 388 43

The cuoxam DP of the dissolved cellulose was 509, that of the fiber 510.

Claims (23)

1. A process for producing a formed article of cellulose by dissolving cellulose in an ionic liquid, forming the viscous solution into a formed article and regenerating the cellulose, which comprises

   a) cellulose or a cellulose mixture being dispersed in water by shearing to the individual fiber, pressed off and the press-moist cellulose or cellulose mixture being

   b) dispersed in the ionic liquid in the presence of basic substances, the water being removed under shearing, increasing temperature and decreasing pressure and converted into a homogeneous solution,

   c) feeding the solution through one or more temperature-controllable tubular lines and a pressure-equalizing apparatus to at least one spin pack,

   d) the solution in the spin pack passing through a filter, a distributor plate configured as a heat exchanger and the spinning capillary or capillaries or the slot of the spinneret die or dies,

   e) leading the solution jets which have been formed into filaments or a film through a conditioned gap with stretching,

   f) the oriented jets of solution being coagulated by treatment with a temperature-controlled solution which is miscible with the ionic liquid but constitutes a coagulant for the cellulose and, at the end of the coagulation bath sector, being separated from the coagulation bath by diversion or deflection,
   and

   g) the formed article in the form of filament yarn, fiber tow or film/membrane being withdrawn, subjected to a single or multiple stage coagulant wash, spin finished and dried or cut into staple fibers, spin finished and dried.
2. The process according to claim 1 that utilizes chemical pulps from wood or cellulosic fibers from annual plants, such as cotton linters, produced by the sulfite, sulfate/prehydrolysis sulfate or organosolve process using elemental chlorine free (ECF) and/or total chlorine free (TCF) bleaching.
3. The process according to claim 1 that utilizes celluloses of medium molar masse (cuoxam DP 400-800) in admixture with high molecular weight (cuoxam DP 800-3000) or low molecular weight (cuoxam DP 20-400) celluloses.
4. The process according to claim 1 that utilizes 1,3-dialkylimidazolium halides as ionic liquid.
5. The process according to claim 1 wherein the ionic liquid has added to it for stabilization, before and/or during the dissolving, basic substances of low vapor pressure in such an amount that the suspension of cellulose/aqueous ionic liquid has a pH ≥ 8.
6. The process according to claims 1 and 5 wherein the basic substances of low vapor pressure are alkali metal hydroxides.
7. The process according to claim 1 wherein the spinning solution contains further stabilizers in the form of organic compounds having at least one conjugated double bond and two hydroxyl or amino groups, preferably hydroquinone, phenylenediamine, gallic esters or tannins.
8. The process according to claim 1 wherein the ionic liquid consists of a recycled coagulation bath.
9. The process according to claim 1 wherein the aqueous coagulation bath is subjected to a hot treatment with alkaline hydrogen peroxide solution, metal ions entrained via ion exchangers are removed and the ionic liquid is concentrated by distillation.
10. The process according to claim 1 wherein the cellulose concentration and the molar mass of the cellulose or cellulose mixture are chosen such that at 85 °C a zero shear viscosity in the range from 1000 to 100 000 Pa s and preferably in the range from 1000 to 80 000 Pa s for the spinning solution and a relaxation time in the range from 0.5 to 90 s becomes established.
11. The process according to claim 1 wherein the spinning solution does not attain the spinning temperature until passing through the distributor plate configured as a heat exchanger.
12. The process according to claim 1 wherein the spinning solution is formed in spinning capillaries 0.4 to 5 mm in overall length (l), having a cylindrical portion (L = 0.5 - 3 D), a conical portion (l-L) and an outlet diameter (D) of 0.05 to 0.25 mm having a circularly round arrangement of the spinning capillaries for filament yarns and a rectangular arrangement of the spinning capillaries for fibers.
13. The process according to claim 1 wherein the spinning solution is formed in slot dies 0.1 to 2.0 mm in thickness to form flat film or in circular slot dies 0.1 to 1.5 mm in gap width to form blown film.
14. The process according to claim 1 wherein the sheet of filaments passing through the conditioned stretching zone is additionally subjected to a conditioned stream of gas.
15. The process according to claim 1 wherein the surface area increase per unit time ΔȮ_a in the course of forming the cellulose solution in gap a satisfies the relation $$\mathrm{\Delta }{\dot{O}}_a=3.6\cdot {10}^{-2}\frac{T_{10}\cdot v_a}{D_A\cdot {\rho }_L\cdot c_{\mathit{Cell}\mathrm{.}}}\left(\sqrt{{\mathit{SV}}_a}-1\right)<200{\mathrm{cm}}^2/\min$$

    

    
    where T₁₀ is the fiber fineness in dtex, ν _a is the withdrawal speed in m/min, D_A is the outlet diameter of the spinning capillary in cm, ρ _L is the density of the spinning solution in g/cm³ and c_Cell. is the cellulose concentration in % by mass.
16. The process according to claim 1 wherein the rate of surface area increase ν _an in gap a satisfies the relation $${\bar{v}}_{\mathit{an}}=10\frac{\mathrm{\Delta }{\dot{O}}_a}{\alpha }<500\mathrm{mm}/\min$$

    

    
    where ΔȮ_a is the surface area increase in cm²/min and a is the gap length in cm.
17. The process according to claim 1 wherein the filament yarn sheet passes through the coagulation bath and through an opening, in the floor of the coagulation bath container, which is formed by a yarn-guiding element, is separated from the coagulation bath stream by being diverted at an angle β < 70 ° and is transported over a godet roll.
18. The process according to claim 1 wherein the fiber tow filament sheet passes through the coagulation bath, is separated from the coagulation bath by being deflected over a rod or roller at an angle > 90 ° and is transported over a pair of godet rolls.
19. The process according to claim 1 wherein the flat film is led through the coagulation bath over a roll, is deflected at an angle of > 90 ° using that roll and is separated from the coagulation bath and transported over a second roll.
20. The process for producing cellulose fibers or filament yarns from chemical pulps and ionic liquids as a solvent according to one or more of claims 1 to 12 and 14 to 18 wherein there is used apparatus consisting of a temperature controllable tubular line (1) and pressure-equalizing apparatus (2)

    ● a spin pack (3), solution filter (4), temperature controllable heat exchanger (5) with seals (8), inflow chamber (6) and spinneret die (7)

    ● a stretching zone (9) with gas supply/- distribution (10)

    ● a coagulation bath (11) with inflow chamber (12), overflow (13), yarn-guiding element/floor opening (14), receiving trough (15), pump (16) and thermostat (17) and

    ● a withdrawal godet roll (18).
21. The process for producing cellulose fibers or films from chemical pulps and ionic liquids as a solvent according to one or more of claims 1 to 19 wherein there is used apparatus consisting of

    ● a rectangular spinneret die (7),

    ● a stretching zone (9) with gas supply/- distribution (10)

    ● a coagulation bath (11) with inflow chamber (12), overflow (13), deflecting roller (14), receiving trough (15), pump (16) and thermostat (17) and

    ● two godet rolls (18).
22. The process according to claim 20 or 21 wherein there is used apparatus in which the heat exchanger (5) consists of

    ● nickelized or chromed aluminum, copper or brass

    ● a well, closed off by seals (8), for receiving the filter pack (4)

    ● a separate heating system (H)

    ● and the flow channels (R).
23. The process according to claim 20 wherein, in apparatus used therein, the volume V in cm³ of the inflow chamber (6) between the heat exchanger (5) and the spinneret die (7) satisfies the relation $$V={\dot{v}}_L\cdot {\lambda }_m$$

    

    
    where ν̇_L is the volume stream of the cellulose solution in cm³/s and λ_m is the relaxation time at the frequency maximum of the relaxation time spectrum of the spinning solution.

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