EP1723273B1 - Process of making false twisted texturized monofilaments - Google Patents

Abstract

The invention relates to a method and device for producing textured, crimped monofilaments. To this end, at least two monofilaments are firstly subjected to a false twist texturing and are then separated and individually wound. The method works considerably faster than prior art methods for crimping monofilaments and results in monofilaments that lead to the production of products having well-undulated products.

Description

The invention relates to a process for the production of textured monofilaments.

Under monofilaments or monofilaments is understood in accordance with DIN 60900 an endless yarn, which consists of a single continuous fiber. Monofilaments or monon filaments (both terms are used synonymously) in the sense of the invention are monofilaments with a diameter of at least 0.025-0.1 mm.

Monofilaments, by virtue of their relatively large diameter, are inherently relatively stiff and, when processed as such into textile products, give a smooth product without good textile feel, in particular the products made from monofilaments have virtually no bulk.

One has already endeavored to texture monofilaments to give the monofilament a crimp, and thus to obtain products with a corresponding bulk.

Among the best known methods of texturing monofilaments are the edge-drawing process, in which the monofilament is drawn at an acute angle over an edge or cutting edge, and also the knit-de-knit process (crinkle process), in which a tube is knitted on a small circular knitting machine , which is then fixed, of the knitting tube is then withdrawn the monofilament at high speed.

Also common is the so-called Trennzwirnverfabren in which are supplied from feed bobbins monofilaments via a delivery mechanism of a device in which the monofilaments are twisted together. Such a device can comprise two upper and two lower delivery mechanisms. The monofilaments are brought together at the so-called twist point, then passed through a heating zone and a downstream cooling zone, after which they are separated at Zwirntrennpunkt means of a Garntrennaggregats and then guided respectively via delivery plants for separate winding or winding.

Between the twist point and the separating point, a certain number of rotations per unit length are initially set. These rotations then propagate continuously in the subsequently supplied monofilament yarn. The twist or rotations thus always propagate during the Trennzwirnkräuselvorgangs. Since the rotation propagation certain limits, the process works relatively slow, so the productivity of this process is not very high.

Out US-A-3 423 924 , such as DE-A-2028959 , a method for the production of textured monofilaments is known, in which two monofilaments of two coils unrolled, textured by means of a false twist device, then separated and separately wound.

Out US-A-3,643,412 is a procedure analogous to US-A-3 423 924 in which yarns are textured instead of monofilaments.

Out US-A-3,645,082 For example, there is known a method for texturing multifilament strands in which the multifilament strands are pulled off overhead, resulting in a twist. In the out US-A-3,645,082 However, the textured monofilaments are no longer separated so that the existing rotation does not interfere with the subsequent process.

A disadvantage of all the methods mentioned above is that the monofilaments textured in this way have only a relatively slight crimp.

Thus, there is still a need for a method that can be used to texture monofilaments at increased speed, as well as a process that provides monofilaments with higher crimping.

The object of the invention is therefore to provide a method by which monofilaments can be quickly textured and which leads to monofilaments which have a satisfactory crimp and thus lead to products with good bulk.

This object is achieved by a method for texturing monofilaments, which is characterized in that at least two monofilaments are unwound from a yarn carrier, subjected to false-twist texturing, and the monofilaments are subsequently separated and wound up separately.

• Scheibenaggregate,
• gekreuzte Riemchen (Murata),
• oder Magnetspindeln

verwendet werden, vorzugsweise ein Scheibenfriktionsaggregat, insbesondere ein dreiachsiges Scheibenfriktionsaggregat. Diese Vorrichtungen sind beispielhaft in Fourne "Synthetische Fasern" Carl Hanser Verlag München Wien 1995, beispielsweise auf den Seiten 432ff beschrieben.As Falschdrahtvorrichtung conventional false-wire units such

• Disk units,
• crossed straps (Murata),
• or magnetic spindles

be used, preferably a Scheibenfriktionsaggregat, in particular a three-axis Scheibenfriktionsaggregat. These devices are exemplary in Fourne "Synthetic Fibers" Carl Hanser Verlag Munich Vienna 1995, for example on pages 432ff described.

The false-twist texturing machine usually has at least one device for heating the monofilaments (heaters), which serves to fix the texturing. The temperature used to fix the texturing depends on the nature of the polymer, these temperatures being well known. For polyethylene terephthalate, this temperature may be, for example, in the range of 170 ° C to 230 ° C.

Furthermore, false twist texturing machines having two or more heaters may also be used. The temperature of the second heater may be above or below the temperature of the heater to fix the texturing. A temperature of the second heater above the temperature of the texturing heater fixer generally results in a harder feel of the textured monofilament. Usually, the temperature of the second heater 10 to 40 ° C, preferably 20 to 30 ° C below the temperature of the heater for fixing the texturing.

The yarn tension that is used to texturize the monofilaments can vary widely, depending on the diameter of the monofilament. Preferably, the thread tensile forces are in the texturing in the field from 0.07 to 0.6 cN / dtex, more preferably in the range of 0.15 to 0.4 cN / dtex, these data referring to the diameter of the monofilaments before texturing the monofilaments.

For separating the false-twist textured monofilaments, a separation twist aggregate is particularly suitable. Such an aggregate is also known per se and, for example, in Fourne "Synthetic Fibers" Carl Hanser Verlag Munich Vienna 1995, for example on pages 436ff described.

For carrying out the process according to the invention, customary monofils from the known fiber-forming polymers such as polyesters, in particular polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polytrimethyl terephthalate (PTT), polyoxymethylene (POM), polyamides (PA), in particular polyamide 6 and polyamide 66, polyolefins, are suitable in particular polyethylene (PE) and polypropylene (PP).

The monofilaments may already have a certain orientation due to the conditions prevailing in the extrusion of the polymers, wherein preferably so-called POY yarns, ie partially oriented yarns or " partially oriented yarns " are used. Another production process is the spinning process, in which fully stretched monofilaments are produced and wound up (FOY = fully oriented yarns). These fully drawn monofilaments can also be textured by the process of the invention.

If partially oriented yarns are textured, they can be stretched simultaneously with texturing. The draw ratio is preferably in the range from 1: 1 to 1: 2.5, this size being dependent, for example, on the polymer used for producing the monofilaments and / or the orientation of the monofilaments after spinning. For example, in PET, the draw ratio may be in the range of 1: 1.7 to 1: 2.3. at PTT and PBT are often used in a draw ratio of 1: 1.1 to 1: 1.7, without this being a limitation.

The monofilaments are generally unwound from a yarn carrier such as bobbins and fed to the texturing device, wherein it is important that the monofilaments are not twisted together prior to the texturing process so that unwanted rotations that would interfere with the separation process are not adjusted prior to the texturing process ,

Preferably, two monofilaments are fed to the texturing device, however, other monofilaments may also be used, e.g. For example, three or more.

The monofilaments can be passed through the false-twist device at high speed. In this case, customary texturing speeds of, for example, 300 m / min to 1200 m / min, preferably 300 m / min to 800 m / min, preferably 500 to 800 m / min, in particular about 500 m / min are particularly suitable.

Thus, speeds can be achieved which are equal to the speeds that are possible in the texturing of multifilament yarns with the false-twist method.

After the false twist process, the monofilaments are separated and returned to a yarn carrier, e.g. B. wound on coils or wound up and then fed to further processing. Accordingly, the monofilaments touch during texturing according to the false-twisting process.

As a device for issuing the false twist are conventional devices, as they are known for false-twist texturing of multifilament yarns. Particularly suitable is a disc frictional aggregate, as described on page 434 in the previously set forth by Fourne. An embodiment with three axes is preferred.

A double-ended false-twist unit is also advantageous, also shown on page 434 in the paper by Fourne (Murata, Osaka, Japan).

For carrying out the method according to the invention, in particular a uniform apparatus which is composed of a device for false-twist texturing and an integrated or immediately following yarn-separating device is suitable.

However, it is also possible to separate the two parts of the apparatus and the processes texturing and separating spatially and temporally and to arrange them at a greater distance. In principle, it is even possible that the two devices are arranged separately, so that first the false-twist texturing process can be carried out, the so-textured monofilaments can be stored as an intermediate product or sent as such and then optionally separated with a corresponding time interval. The disadvantage here, however, is that higher production costs arise through the separation of the processes. However, the quality of the product according to the invention does not detract from this.

The monofilaments obtainable by the present process are distinguished by excellent properties, in particular by higher bulk.

Preferably, the textured monofilaments, especially polyester monofilaments, for example PET, exhibit a tear strength in the range of 20 to 50 cN / tex, more preferably in the range of 35 to 45 cN / tex. The elongation at break is preferably in the range of 15 to 40%, especially in the range of 20 to 32%. The tear strength and the elongation at break can be determined according to DIN EN 2062.

The texturing of the monofilaments can be adjusted by a person skilled in the art to a predetermined size over a wide range. For example, so-called SET yarns can have a crimp of at least 4%, preferably at least 6% and particularly preferably at least 7%. The crimping of HE yarns (highly elastic yarns) can be at least 20%, preferably at least 30% and particularly preferably at least 40%. The crimp resistance of the textured monofilaments is preferably at least 50% and more preferably at least 65%. The crimping and the crimp resistance can be determined according to DIN 53840.

The monofilaments textured according to the invention show a surprisingly low gloss. The gloss of the textured monofilaments is preferably at most 20 (gloss level), particularly preferably at most 12.5 (gloss level). The gloss can be determined according to DIN 67 530.

The monofilaments textured according to the invention are particularly suitable for the production of textile fabrics, for example fabrics, in particular curtain fabrics and for clothing fabrics.

The invention is explained in more detail by the following examples, without the invention being restricted to these examples.

Examples 1-4 describe spinning and stretching, and Examples 5-7 relate to texturing and separating the monofilaments.

example 1 Spinning and stretching or spinning lines

PET chips with an intrinsic viscosity of 0.64 dl / g, a melt viscosity of 210 Pas, a melting point of 257 ° C were dried at a dryer temperature of 135 ° C in a drum dryer to a water content of 40 ppm.

The chips were melted in an extruder, the melting temperature being 290 ° C. The melt was fed via a heated melt line of 295 ° C the spin pump. The amount of melt supplied to the nozzle pack was 24.8 g / min (for a titer of 80 dtex f 2). The melt was extruded through a die plate of 65 mm diameter and 2 holes of 1 mm diameter and 4 mm length. The nozzle pressure was 135 bar.

The monofilaments are cooled in a blower shaft with a blowing length of 2.5 m by transverse flow blowing. The blown air had a humidity of 70% relative humidity and a speed of 0.45 m / sec. and a temperature of 20 ° C.

The solidified monofilaments are prepared at a nozzle / oiler distance of 3.5 m with a conventional textile spinning preparation. The preparation overlay was 0.30% based on the bifilar wound monofilament. The bifilar yarn is fed via a godet pair in S-shape of the winding machine. As a winding machine, the type LFW 35 from Barmag at 3100 m / min. operated. The winding tension was 0.05-0.1 cN / tex.

Example 2

Monofilaments according to Example 1 are drawn on a stretch winder. The bifilar yarns are fed to a stretch winder by the company Zinser, type D 548. The stretching takes place here by 2 godets, between which a plate heater is arranged. The first galette has a temperature of 105 ° C, the plate heater a temperature of 195 ° C and the 2nd Galette room temperature. The total draw ratio for the spin titer 80 dtex f 2 was 1.82 (final titer 44 dtex f 2). The winding speed was 1050 m / min.

Example 3

Monofilament according to Example 1 to the effect that instead of 2 nozzle holes only 1 nozzle hole is used with a correspondingly reduced amount of melt.

Example 4

Production of the monofilaments up to and including the preparation of the threads Example 1. In addition, the threads are drawn in the spinning process. Here, a first heated (90 - 120 ° C) Galettenduo is looped with 10 -15 entanglements. The speed of the duo is 1000 m / min. The threads then enter the drafting field and are heated on the second duo (3000 m / min) at 130-180 ° C. with 10 - 15 wraps. Subsequently, the drawn threads are fed to the winder according to Example 1. The draw ratio between Galettenduo 1 and 2 was 1: 3.

Example 5

Monofilament threads according to Example 1 are texturized on a false-twist texturing machine from Barmag, type FK6-V-900. The bifilar threads are thereby unrolled from the POY coil and fed to the first delivery W ₁ .

The texturing parameters for the production of SET and HE yarn are listed in Table 1, the textile physical data of the false-twisted monofilaments summarized in Table 2. 6 mm PU disks of configuration 1-3-1 were used.

As soon as the threads (false twisting wire), which have been turned back to 0, leave the texturing unit, they are fed to a separating / twisting unit from Retech * and separated there. The then separately present false-twisted yarns are wound simultaneously at texturing speed according to Table 1 on the FK-6-V-900 individually.

The separation unit is available from Retech AG, CH - 5616 Meisterschwanden. The principle of this aggregate is in EP 0 106 067 A2 described. This disclosure is expressly referred to here. <u> Table 1: Texturing Parameters / Stretch Texturing </ u> experimental parameters example 1 Example 2 Example 3 final titer [Dtex] 44 f 2 22 f2 44 f 2 CS * texturing [M / min] 450 600 500 draw ratio 1: 1,92 1: 2.08 1: 2,15 d / y ratio 1.75 1.95 1.85 Temperature heater 1 I ° CJ 190 185 180 Temperature heater 2 I ° CJ 160 ----- 160 Thread tension F ₁ [CN] 23 16 14 Thread tension F ₂ [CN] 25 22 20 • CS = Trevira CS® material property example 1 Example 2 Example 3 Titer (effective) [Dtex] 46.9 24.2 47.8 tear strength [CN / tex] 38.0 37.5 36.1 elongation at break [%] 29.5 23.4 24.7 crimp [%] 7.8 40.3 6.3 curling [%] 75 68 72

Example 6:

False-wire textured yarns are textured according to Example 5, not immediately separated simultaneously, but bifilar false-wire texturized and wound on the texturing machine. Subsequently, the threads are separated in time and space separated on a stretch winder. The bifilar false-twisted yarn is unrolled and passed over the separating yarn guide and fed to a take-off feeder, and finally wound up at 1000 m / min each monofilament.

Claims (16)

1. A method for the production of textured monofilaments, characterized in that at least two monofils are unwound from a yarn carrier, subjected to a false twist texturing and the monofils are subsequently separated and wound individually.
2. The method according to claim 1, characterized in that a disc friction unit is used as a false twisting device.
3. The method according to claim 2, characterized in that a triaxial disc friction unit is used.
4. The method according to at least one of claims 1 to 3, characterized in that the monofilaments are separated in a twine separating unit following the false twist texturing.
5. The method according to at least one of claims 1 to 4, characterized in that the false twist texturing and the separation is performed at different places and/or times.
6. The method according to at least one of claims 1 to 5, characterized in that monofils made of polyester, in particular polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), polyoxymethylene (POM), polyamides (PA), in particular polyamide 6 and polyamide 66, polyolefins, in particular polyethylene (PE) and polypropylene (PP), are used.
7. The method according to at least one of claims 1 to 6, characterized in that so-called POY monofils are used.
8. The method according to at least one of claims 1 to 6, characterized in that FOY monofils are used.
9. The method according to at least one of claims 1 to 8, characterized in that the texturing speed is in the range of from 500 to 1200 m/min.
10. The method according to at least one of claims 1 to 9, characterized in that the yarn tensile forces with which the monofils are textured are in the range of from 0.07 to 0.6 cN/dtex.
11. The method according to at least one of claims 1 to 9, characterized in that the tear strength of the produced monofils is in the range of from 20 to 50 cN/tex.
12. The method according to claim 11 or 12, characterized in that the elongation at tear of the produced monofils is in the range of from 15 to 40%.
13. The method according to claim 11 or 12, characterized in that the curling of the produced monofils is at least 4%.
14. The method according to claim 13, characterized in that the curling of the produced monofils is at least 20%.
15. The method according to at least one of claims 11 to 14, characterized in that the curling resistance of the produced monofils is at least 65%.
16. The method according to at least one of claims 11 to 15, characterized in that the gloss of the produced monofils is at most 20% (degree of gloss).