CZ206697A3 - Process for producing extruded article - Google Patents

Abstract

A method of manufacturing extruded articles of lyocell is described wherein a solution of cellulose in a tertiary amine N-oxide is extruded by way of a die (2) through an air-gap (3) into a coagulating bath (5), air being supplied to and discharged from the air-gap (3), characterised in that the air-gap (3) comprises a first region (9) adjacent the face (2a) of the die (2) and a second region (12) more remote from the face (2a) of the die (2), the moisture content of the air supplied to the first region (9) being maintained at a lower value than the moisture content of the air supplied to the second region (12). The method provides improved spinnability and may provide lyocell filaments with a reduced tendency to fibrillation.

Description

Process for producing extruded product

Technical Field ·· ΜΗ

The invention relates to a process for the production of cellulosic products in which a solution of cellulose in a tertiary amine N-oxide is extruded into a coagulation bath.

It is known that cellulose can be dissolved in certain N-oxides of tertiary amines (which, for simplicity, can also be called amine oxides) to form a solution or, more specifically, a spinning solution that can be extruded into a coagulation bath to form a product such as fibers or foil. The spinning solutions generally contain a small amount of water and the coagulation bath is usually an aqueous bath. The coagulated product is then washed to remove residual amine oxides. This process is an example of solvent spinning, and the fibers produced in this way can be called solution spinning fibers or lyocell fibers. An example of a useful amine oxide solvent is N-methylmorphol: i-N-ox: i.d (NMMO).

BACKGROUND OF THE INVENTION

U.S. Pat. No. 4,261,943, the contents of which are hereby incorporated by reference, discloses such a solution spinning process in which a solution of cellulose in aqueous NMMO is forced through a spinneret through an air gap, which may be, for example, 5 or 30 cm long. The fibers are then passed through a water bath to form a lyocell fiber. This patent also discloses a solution spinning process wherein the fibers in the air gap are coated with a cellulose-insoluble liquid, e.g. water, which is carried out immediately after extrusion. This method reduces the tendency of the fibers to bond to each other at ♦, <

»· · 1

I · 4 «« · * ♦

** ·· air gap passage

WO-A-93/19230 discloses a solution spinning process in which fibers in the air gap are cooled before entering the coagulation. bath, e.g., intensive air cooling, the solution may be 90-110 ° C, the cooling air temperature -5 - + 5 ° C and the air gap length 60-145 mm.

by subjecting the spinning temperature

SUMMARY OF THE INVENTION

According to the present invention, the process for producing extruded lyocell products is performed by extruding a solution of cellulose in a tertiary amine N-oxide through an air gap to coagulate. The method is characterized in that the air gap comprises a first region adjacent to the spinneret. and a second region adjacent to the bath wherein the humidity of the air that is supplied to the first region is kept lower than that of the air supplied to the second region.

The extruded lyocell product may also be a film or, preferably, fibers (including not only spinning fibers that can be subsequently chopped to produce yarn, but also yarns with continuous fibers). If the product being manufactured is fibers, the extrusion device is generally called a spinning device. the nozzle and counter-process can generally be called spinning.

Air length gap between nozzle and coagulation spa Yippee preferably in the range 10 up to 60 mm, still in more preferably 15 to 100 mm or 20 to 60 mm. Yippee Clear that gas in the blower trysce J ^e preferably air, d laL .inertní gases or mixtures gases, eg nitrogen can be used.

Β · · ·, t t t • • • • • • ··· * * · · · · ·

In Β · * * · · · · · · · · · · ·

Each of the two air nozzle regions may have the same or different lengths. In one possible embodiment, which may often seem advantageous, the length of the first region is less than the length of the second region. The first region is preferably 3 to 10 mm so that the second region occupies the remaining air gap length. The cellulose solution (which can also be called a spinning solution) is usually extruded downwards and passes through the blower region. nozzles. The air is preferably supplied and withdrawn by means of air tanks or air nozzles in a direction substantially transverse to the direction of the passing fibers, so that it is substantially horizontal when using conventional extrusion techniques. In such a transverse configuration, the passage of air through the air reservoir can usually be referred to as cross-draft. The speed of the air supplied to the air reservoir in both regions is preferably in the range of 1 to 20 m / s, more preferably 2 to 10 m / s. It is clear that the air velocity should be high enough to maintain different atmospheric conditions around the spinneret extrudate within the two air-blowing regions, but not so high as to interfere with the passage of the extrudate, i.e. the formed fibers. Generally, higher speeds can cause such distortion in longer air gaps. The air velocity of the first and second regions by air blowing may be the same or. different. Appropriate air speeds can be determined in each particular case by a simple test.

Methods for removing air from one or both of the regions may be accomplished by suction. Air can be supplied and exhausted from the air gap by a suitable blower and suction nozzles. It is clear that separate, blowing nozzles are required for each of the first and second regions. One or more suction nozzles may also be used. In a preferred embodiment, each blower nozzle faces a suction nozzle that is similarly sized. This arrangement has the advantage of:. This allows for better regulation of the atmospheric conditions around the extrudate along the entire gap region in which the extrudate is blown through the air. In particular it is

I ft ftftft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft.

if ft ft length first

I t

and

The supply air temperature in the air gap is generally around ambient temperature, e.g. at 0-40 ° C, and very often it is 20-30 ° C. The temperature of the dope supplied to the nozzle is generally in the range of about 80-125 ° C and the gas flow therefore serves to cool the extrudate in the air gap. It is common practice to increase the speed of the extruded product in the coagulation bath so that it is higher than the extrusion speed through which the spinning solution passes through the nozzle. Usually, the factor of this increase is 2.5-25, so that the extrudate is stretched, which serves to improve the mechanical properties. The humidity of the air supplied to the first region is preferably, in the range of 0-20, even more preferably 0-10 grams of water per kilogram of air, the humidity of the air supplied to the second region is preferably in the range of 5-30 grams of water per kilogram of air.

Lyocell fibers generally tend to fibrillate especially when subjected to mechanical stress during a hot part of a process such as a process in which they are further processed, such as spinning, grinding or dyeing. During fibrillation, the fibers partially tear off the surface, producing individual fibers (as well as yarns and products containing it) and their hairy appearance may be aesthetically undesirable. Surprisingly, it has been found that the fiber produced by the process of the invention shows a lower tendency to fibrillation than the fiber produced by conventional spinning techniques.

It is known that the spinning of lyocell fibers in the spinning of lyocell fibers can extrudate the spinning solution, e.g. in the form of fibers, occasionally to remain in the air gap. This defect can be referred to as a loss of spinning stability or poor spinning. Poor wettability can be detected by observing the injured or

---- 5 «Β · · _. · ^ *

9 9

9

449 · · «4 4 4 4 9 *

9 9 4

944 99

H ÍS®9

99 4 cut fibers in the total product or in some cases by. records complete yarn breakage in the air gap or in the spin bath. Surprisingly, it has been found that the process of the invention solves better spinning stability than conventional techniques, especially at longer air gaps. This effect is difficult to quantify but can be easily detected by observation.

The average degree of polymerization (D.P. of cellulose in the dope may generally be in the range of from 250 to 250)

2000 and preferably ranges from 500 to 2000, even more preferably from 750 to 1000. It has been found that good spinning is achieved, over a wide range of conditions, if D.P. cellulose is in the range of 750-1000. Degree of polymerization D.P. The cellulose is usually controllable by viscosimetry of a dilute solution of cellulose in an aqueous solution of a metal amine complex, e.g., an ammoniacal copper complex. A method based on TAPPI Standard T206 is a useful method and is further described herein as Test Method No. 3 in anhydroglucose units.

D.P. cellulose is measured per molecule. It is clear that the D.P. in this case the mean viscosity D.P.

The invention will now be described with reference to the accompanying drawings, which represent schematically an apparatus for carrying out the method according to the invention.

As can be seen in the figure, the solution of cellulose in aqueous amine oxide is also supplied to the spinnerette 2 by means of a pump. The spinning solution may, for example, contain 5 to 25% by weight of cellulose, 70 to 85% by weight of NMMO and the temperature may range from 80 to 125 ° C. The spinning solution is extruded downwards. through the orifices of the spinnerets 2 into the air gap 3, maintained at a temperature below the temperature of the spinning solution,

------, ph.

»·» »» »»

HM ··· «> 0 • • v <

and b * b &lt; - &gt; 9 &lt; 9 &gt; β while obtaining a solid form of the fiber bundle 4. The fibers 4 then proceed to the aqueous coagulation bath 5 while partially passing through the roller 6 and being discharged for rinsing, drying and other conventional operations. The peripheral speed of the roller 6 is higher than the speed of the spinning solution at the entrance to the openings of each spinneret 2 so that the fibers 4 are drawn. The elongation of the fibers takes place predominantly in the air gap 3.

The first part of the air is supplied through a blower nozzle 7 to the air gap 3 in the first region 9 adjacent to it. to the spinnerette 2 and is discharged from the air gap 3 through the suction nozzle 8, so that air passes through the air gap 3 transversely to the direction of passage of the fibers 4. Nozzles 7. 8. are arranged in such a way that the process makes it possible to maintain the temperature and humidity of the atmosphere of the first region 9 adjacent to the face 2a of the spinneret 2 at a desired value. The second part of the air is supplied in a similar manner to the air gap 3 in the second region 12 farther from the spinnerette 2 and utilizes a blower nozzle 10 and a discharge suction nozzle 11. The nozzles 10, 11 are arranged such that this method allows the temperature and humidity of the second region 12 located between the first regions 9a and the coagulation bath 5 to be maintained at the desired values. The nozzles 7 and 10 increase the amount of air supplied to the passing fiber bundle 4. The humidity of the air supplied by the blower nozzle 7 is lower than the humidity of the air supplied by the blower nozzle 10. The temperatures of the two supplied air portions may be the same or different.

Although the figures show the delivery of two different portions of air of different properties to the air gap, it is understood that three or more different from each other, such portions may also be used, each of which. is supplied to a separate air gap region without departing from the basic idea of the invention. The tendency to lyocell fiber fibrillation can be monitored by the following test methods:

DETAILED DESCRIPTION OF THE INVENTION

- 7 ~ Test method 1 (sand test)

A small piece of fiber containing 100 to 200 monofilaments is chopped to a length of 5 mm. The short fibers are placed in a 20 ml container containing 4 g glass microscopic particles, and 8 ml of water is added. The vessel is sealed reliably and shaken on a Stewart shaker at 2800 cycles per minute for 20 minutes.

A portion of the fibers was removed and placed on a microscope slide. The fibrillation index (CI) is calculated from optical microlines on fibrillating fibers. The total lengths of fibrils, f, attached to the base fiber of length L, are determined by measuring under a microscope. The fibrillation index is given by the equation

_Cf = 2f / L

This operation can be performed manually or by image analysis. Alternatively, a set of standard microlips can be used for comparison. An experienced fiber worker can easily handle this method. In practice, it is not possible to measure fibrillation indices having a value of greater than about 30, since problems with the visibility of a large number of fibrils arise. Data is measured. at the center of the 5mm fiber and at the end. Experience has shown that the result correlates well with machine execution and therefore only these numbers are referred to as (TMI).

Test Method 2 (Color Washing)

The following method was used to determine the fibrillation index (F.T ..). The fiber samples were stacked according to the increasing degree of fibrillation. The standard fiber length from each sample was then measured and the number of fibrils (fine hairs remaining from the fiber base body) along the entire standard length was then summed. Then she was

4. 4 «4 4

444 • 4

4 4 9 4

4 9 4 · 9 • 4 · 44 4

The length of each fibril was measured and a number was calculated for each fiber showing the number of fibrils multiplied by the mean length ^{r of the} fibril. The fiber showing the highest value of this critical number was then labeled as the most fibrillated fiber and was assigned a fibrillation index of 10. The complete non-fibrillated fiber was given a fibrillation index of 0 and the other fibers were labeled between 0-10 based on microscopically determined critical numbers.

The measured fibers were then used to create a standard ascending scale. To determine the fibrillation index of any other fiber sample, five or ten fibers under the microscope were visually compared to standard calibrated fibers. Visual determination of the critical numbers for each fiber was then the basis for determining the fibrillation index of the test samples. It is clear that the visual test and average calculation are in many cases faster than measurements. It has been found that an experienced fiber technologist can easily learn to judge fibers.

The fibrillation index of the articles can be determined on fibers pulled from the surface of the article. Woven and knitted articles having F.I. greater than about 2.0 to 2.5 are not visually good.

Yarn of 1,7 dtex basis. The lyocell fibers were crimped and cut into 30mm fiber samples which were bonded to ₄ yarns of 20 tex. Yarn was chopped into 80 mm long pieces ^Λ which have been washed and stained in a slightly blue tint. The chopped products were rinsed at 40 ° C in a domestic washing machine and dried in a domestic hot air dryer. The fibrillation index was then determined on the fibers pulled from the surface of the treated dry product after rinsing and dyeing. This index was also determined after one or more wash / tumble cycles.

4

Test method 3 (measurement of viscosity and D.P. of ammoniacal copper solution.

a · a • · · and · · »· a 9 • • · and a and a ♦ and * and a and ♦ aa and a * • • a and and a • ·· · 44 4 a · a aa aa a

This text os-63. Cellulose containing 15 ± is based on TAPPI Standrad T206 i dissolved in an ammonia copper solution of 0.1 g / l copper and 200 ± 5 g / l ammonia, with a nitric acid concentration of less than 0.5 (Shirley)

Institute standard), in an amount such that a solution of a preselected exact concentration (about 1%) is formed. The flow rate of the solution at about 20 ° C / min. Is lower than the viscosity after standard viscosity. Viscosity value D.P. is determined using an empirical equation

D.P. = 412.4285 ln [100 (t-k / t) / n C.] · - 348

Where t is the flow time in seconds, k is the gravitational constant, C is the tube constant and n is the water density in g / ml at the test temperature (0.9982 at 20 ° C).

The invention is illustrated. the following examples, in which parts and ratios are by weight except where expressly stated otherwise.

Example 1

A spinning solution was prepared containing wood pulp slurry (different concentrations, different polymerization stages (D.P.)), as described below, 74-80% NMMO and 7.5-12.6 water. This solution was extruded through a spinneret (115 ° C inlet temperature) containing 95 orifices, each 80 microns in diameter, through an air gap of length below, into a coagulation bath containing 25% NMMO and 75% water at 25 ° C, thereby formed lyocell fiber. The air was blown crosswise and passed through the extruded fibers through the upper and lower inlets. The depth of the first, upper region of these transverse leads was about 4 mm. Second, lower transverse • · ··· · • · * · · · ·

A V 9 * · · · ··· ·

9 9 9 9 »19 9» 99 9 the inlets were designed so that the air flow from the manually adjusted electric fan was blown into the appropriate space via a suitably directed shaped funnel. The humidity of the lower transverse blowing air was increased, if necessary, by allowing a small amount of low pressure steam into the blowing air at the inlet of the funnel, thereby increasing the relative humidity (R.H.). The fiber was rinsed in water to remove residues. NMMO and dried. Fibrillation tendency was then tested by Test Method 1. The fiber samples were then chopped to form pieces of fiber which were then wrapped in yarn. Yarn quality was assessed visually, and was assigned a value of 1 (very poor) to 5 (very good). The details of the experiments and the results are given in Table 1 below.

Table 1

Cellulose% Cellulose D.P. Yarn Quality Gluing

Cjr (TM1) fibers

Spinning speed 60 m / min, air gap 20 mm, top

blowing (first ob I as t) 18 ° C / 0% R. H. , lower blowing (second area) 20 ° C R.H. 15 Dec 850 • 4 5.5 No 15 Dec 630 5 ' 6.5 No 15 Dec 472 5 9.4 No 12.5 630 4 5.9 No 10 850 4 5.3 No

Spinning speed 30 m / min, air gap 75 mm, top blow (first zone) 20 ° C / 0% R.H. , bottom, blowing

v. ata - 11 - • * 44 * Φ • 4 · • 4 4444 444 43 4 4 4 · 4 4 4 4 4 44 * 4444 4 4 4 4 4 445 44 44 4 (second round 15 ast) 20 ° C / 40 850 % C R.H. 4 6.6 No 15 Dec 630 5 4.9 No 15 Dec 472 4 3.3 some 12.5 630 3 4.1 some 10 850 4 4.2 No Spinning speed 30 m / min, air blowing (first region) 20 ° C / 40% (second region) 30 ° C / 60% R.H. gap 150 R.H., bottom mm, top width. ofukování

15 Dec 850 3 3.2 some 15 Dec 630 3 0.0 little 15 Dec 472 2 * 0.1 Yes 12.5 630 1 0.0 Yes 10 850 4 2.5 Yes Speed spinning 30 m / min, air 150 mm gap, upper ofukování (first region) 20 ° C R.H. , lower blowing (second area) ° C R.H. 15 Dec 850 4 3.8 little 15 Dec 630 2 1.3 individual 15 Dec 472 2 0.0 some 12.5 630 1. 0.7 Yes 10 850 1 3.5 Yes Speed spinning 30 m / min, air 150 mm gap, upper ofukování (first region) 20 ° C R. H. , lower blowing (second area) ° C R.H. 15 Dec 850 4 0.0 No 15 Dec 630 3 1.5 minimum 15 Dec 472 2 0.0 Yes 12.5 630 1 2.1 Yes 10 850 1 4.8 Yes

Example 2

Example 1 was repeated except that the spinning solution contained 12.2% wood pulp slurry (D.P. 600),% NMMO and 9.8% water. The fiber thus prepared was tested for fibrillation tendency using Test Methods 1 and 2. Details of the experiments and results are given in following table 2.

Table 2

Air ° C / RH% Quality C _f (TMI) Glued FI (TM2)

Upper Bottom. yarn fiber rinse / dyeing 1V / T

Spinning speed 60 m / min, air gap 20 mm:

20/40

30/60

11.0

9.0 no no

4.7

4.7

5.5

6.0

Spinning speed 30 m / min, air gap 150 mm:

30/60 3.0 0.1 yes 1.7 4.1

20/40 30/60 2.7 1.7 yes 1.9 1.9

Spinning speed 10 m / min., Air gap 75 mm:

30/60 3.3 3.6 some 2.5 3.5

60/40 30/60 4.0 0.7 no 1.0 2.0

Spinning speed 10 m / min, air gap 150 mm

20/40 1,3 1,2 individual

20/40 2.0 3.1 yes

2.7

5.2

Experiments with 20 rotating head at mm air gap were performed at 110 ° C. Longer head and air gap experiments were performed at 90, 100, 110 ° C. Between the results there were and therefore averages were used.

small differences

Example 3

Example 1 was repeated, except that the temperatures and relative humidity of the upper part of the supply air were 20 ° C and% and the lower parts of the supply air were 30 ° C and 60%,

9999 ‘*

9

9999 999

99

In 9 * 9 · 9 9 0

9 9 9

9 9 9

999 99 99 »

»»

Table 3

Cel. D.P Cel. % Speed spinning m / raine Air mezen mm Speed air m / sec Tension yarn Stability spinning C _f - 630 15 Dec 1-0 2.0_  7 44 Good 3.8 630 15 Dec 10 20 May 8 53 Good 1.9 ' 63.0 15 Dec 10 40, 2 25 Spatná 0.0 630 15 Dec 10 40  8 52 Good 0.0 630 15 Dec . 10 80 · 2 45 Good 0.0 630 15 Dec 20 May 20 ' 7 100 ALIGN! Good 7.1 630 15 Dec 20 May 20 May 8 165 Good 6.4 630 15 Dec 20 ' 40 2 80 Spatná 5.8 630 15 Dec 20 May 40 8 148 Good 310 630 15 Dec 20 May 80 2 69 Okay 2.1 630 15 Dec 40 20 May 7 120 Velni Good 10.6 630 15 Dec 40 20 May 8 .. 150 Very okay 9.5 630 15 40 40 7 J 150 | Very Good 6.2 630 15 Dec 40 40 ⁸ 1 225 | Vetad Good ó.O 630 15 Dec 40 80 2 126 Good 5.4

Tt tt tt tt tt

IN Cei D.P Cel  % Speed spinning mZmin Air. mezen mm Speed vzdacfan m / sec Tension yarn Stability spinning C _f y and 350 15 Dec .10 20 ’ 2 240 Very Good 2.7 850 15 Dec 10 20 May 8 1,650 - Good 1.4 850 15 Dec 10 40 2 250 Very Good 0.0 850 15 Dec 10 40 8 920 Poor 1.3 850 15 Dec 10 80 2 220- ' Good. 0.6 850 15 Dec 10 160 2 310 | Okay 0.0 850 '15 20 May 20 May 2 300 Very Good 5.8 850 15 Dec 20 May 20 May 8 900 bad 6.0 850 15 Dec 20 May 40 2 '220. Very Good 2.4 850 15 Dec 20 May 40 ' 8 900 bad 2.0 850 15 Dec 20 May 80 2 220 Very Good 0.2 ' 850 15 Dec 20 May 80 8 280 Good 0.2 850 15 Dec 40 20 May 2 460 Very Good 4.6 850 15 Dec 40 20 May 8 1000 j bad 5.8 850 15 Dec 40 40 2 290 Very Good 5.4 850 15 Dec 40 40 8 800 Okay 5.0 850 15 Dec 40 80 2 210 Very Good 0.0

-15 • fl · fl · fl · fl · «· fl · • • flflfl flfl * flfl flflfl · flflfl • fl flfl flflfl flflfl flfl • fl • flflflfl · flfl • • • · flfl fl flfl"

Cel D.P Cel ' % Speed spinning m / min Air itwram mm Speed air m / sec Tension pHzo Stability spinning C, 850 13 10 20 May 2 57 Very Good 5.1 850 13 10 20 May 8 84 Very Good 3.0 850 13 10 40 2 65 Okay 2.2 350 13 10 40 X 8 151- Good 0.2. 850 13 20 May 20 May 2 110 Very Good 5.5 850 13 20 May 20 May 8 117 Very good ¹ 1.0 '850 13 20 May 40 2 90 ' Good 4.5- 850 13 20 May 40 8 256 Good 6.0 · 850 13 40 20 May 2 140 Very Good 8.9 850 13 40 20 May 8 '170 Very Good 6.8 850 13 40 40 2 130 Good 7.1 850 13 40 40- 8 340 Good 6.0 850 13 40 80 2 110 Okay 5.4

· 9 · 9

- »16 · 9 · 9

9

Yarn tension is a significant number, its higher values mean higher tension. Some portions of the fibers have been observed to be damaged when using longer air gaps, especially at higher air speeds.

Example 4

Magnifying. the solution was prepared containing 13% cellulose (mean D.P. 800), 75% NMMO and 12% water. Was

-ex-t.ru -directed-to-l-s-rz-z-vi-a-forging-sieve tors;^-me-l-a 18,400 holes, each 70 microns in diameter, divided into three parallel rows, each about 1 mm long (83 ° C spinning temperature) through a 30mm air gap into a coagulation bath containing 25% NMMO and 75% water to form a yarn Lyocell fiber. Through the gap air was blown through the fibers in two regions, the upper region at. speed of 12 m / s with. 5mm blower nozzles, located directly at the spinnerette and the bottom area at 9 m / s with a 25mm blower nozzle located behind the bottom of the air gap. The air was sucked out by suction nozzles opposite the corresponding blowing nozzles with the same temperature of the upper (relatively dry) air at

C and its relative humidity was 40% (dew point 6 ° C). The temperature of the lower air stream (relatively humid) was 28 ° C and its relative humidity was 78% (dew point temperature is 24 ° C). The spinning quality and stability were good. The upper air stream was. then removed. Immediately thereafter, the spinning quality deteriorated considerably, and the upper air nozzle had to be quickly renewed to prevent complete yarn breakage (loss of spinning stability) in the coagulation bath.

Claims (13)

PATENT CLAIMS A method for producing an extruded lyocell product, wherein the solution of cellulose in a tertiary amine N-oxide is extruded through an air gap into a coagulation bath, air is supplied to and removed from the air gap, characterized in that the air gap is formed by a first an area adjacent to the edge of the extruder and extending from the distal exit edge of the extruder, the humidity of the air supplied to the first region being kept lower than the air supplied to the second region. Method according to claim 1, characterized in that the length of the air gap is in the range of 10 to 160 mm, preferably 20 to 60 mm. The method of claim 1 or 2, wherein the length of the first region is less than the length of the second region. The method of claim 3, wherein the length of the first region is in the range of 3 to 10 mm. Method according to any one of the preceding claims, characterized in that the air velocity y. supplied to each first region and second region is in the range of 1 to 20, preferably 2 to 10 m / s. « Method according to any one of the preceding claims, characterized in that air is supplied to the first region and to the second region in a direction substantially transverse to the direction of travel of the extrudate. air gap. A method according to any one of the preceding claims, 99 9 9 99 »999 9 9 9 99999 9 - 18 - 99 99 » 99 9 9 9 9 » 9 99 9900 99 99 9 9 9 9 » 9999 999 » characterized s e by that air is supplied to air gaps in first areas even in the second area blowing nozzles, which are separate for each region. ¹ 8. The method according to claim 7, characterized in _that air is discharged from the air gap by one suction nozzle directed against the blowing nozzles. V _9. Method according to claim 7, characterized in that air is drawn from the air gap by separate suction nozzles directed against each blower nozzle and with a similar design. Method according to any one of the preceding claims, characterized in that the humidity of the air supplied to the second region is higher than that of the air / supplied to the first region. Method according to any one of the preceding claims, characterized in that the content of air supplied to the first region is in the range of 0 to 20, preferably 0 to 10, grams of water per kilogram of air. Method according to any one of the preceding claims, characterized in that the humidity of the air The air supplied to the second region is in the range of 5 to 30 grams per kilogram of air. *, The method according to any one of the preceding claims, characterized in that the average polymerization degree of cellulose in solution is in the range of 750 to 1000. Process according to any one of the preceding claims, characterized in that the extruded product is in the form of lyocell fibers.