EP0569890B1 - High tensile sewing yarn and method for manufacturing such a sewing yarn - Google Patents

Abstract

There is described a high tensile sewing yarn composed of at least two, twisted-together multifilament yarn components. The multifilament yarn components forming the thread are textile standard multifilament yarns. The sewing thread has a tenacity (specific strength) which varies between 40 cN/tex and 85 cN/tex, preferably between 55 cN/tex and 75 cN/tex. The process for manufacturing the above-described sewing thread envisages drawing the partially oriented multifilament yarns forming the thread in such a way that each partially oriented (pre-oriented) multifilament yarn is delivered into a main drawing zone coiled around a feed gadget revolving at a first speed and leaves the main drawing zone coiled around a take-off godet revolving at a second speed the second speed being 70 % to 180 %, preferably 140 % to 180 %, greater than the first speed. The drawing in the main drawing zone takes place exclusively between the feed godet and the take-off godet, the take-off godet being heated to a temperature between 160 DEG C and 240 DEG C.

Description

The present invention relates to a high-strength sewing thread with the features of the preamble of patent claim 1 and a method for producing such a sewing thread.

Sewing threads are known in different constructions. For example, sewing threads are offered which consist of two intermingled multifilament threads, one multifilament thread forming the core of the sewing thread and the other forming the jacket of the sewing thread. Furthermore, it is known to construct sewing threads in such a way that a multifilament core material is spun with a fiber thread to form a core thread, in order to achieve the required strengths usually two or more such core threads are twisted together to form a sewing thread.

The production of the sewing threads described above is relatively complex and requires extensive special knowledge.

For example, EP 0 472 873 A1 describes a sewing thread which comprises at least two multifilament thread components, a first thread component forming the core being interwoven with a second thread component predominantly forming the jacket of the sewing thread, forming the sewing thread in such a way that a relatively voluminous one and bulky sewing thread is created.

A high-strength sewing thread with the features of the preamble of claim 1 is known from EP 0 363 798 A2. This known two-component loop sewing thread has a final strength of more than 40 cN / tex, high-strength and in particular high-molecular starting threads being used to produce this sewing thread, which are interwoven to form a voluminous and bulky two-component loop sewing thread. It is expressly apparent from EP 0 363 798 A2 that the loop sewing thread described there has good sewing properties because the loops of the individual filaments are fully retained so that air can be entrained accordingly during the sewing process. However, this is only possible if the known sewing thread is in the form of an untwisted sewing thread.

The present invention has for its object to provide a high-strength sewing thread that has a relatively simple construction.

Furthermore, it is an object of the present invention to provide a method for producing such a high-strength sewing thread, which allows a particularly simple and trouble-free production of this sewing thread.

According to the invention, these objects are achieved by a sewing thread with the characterizing features of patent claim 1 and by a method with the characterizing features of patent claim 9.

The high-strength sewing thread according to the invention, which comprises at least two multifilament thread components and which has a specific strength between 40 cN / tex and 85 cN / tex, preferably between 55 cN / tex and 75 cN / tex, is in contrast to the prior art mentioned above not the construction of a voluminous, swirling sewing thread, but instead the construction of a compact sewing thread. Here, the sewing thread according to the invention has at least two twisted yarn components, the yarn components forming the sewing thread being standard textile multifilament yarns and the sewing thread having a twist coefficient α between 70 and 140.

Das erfindungsgemäße hochfeste Nähgarn weist eine Reihe von Vorteilen auf. So ist es relativ preiswert herzustellen, da hierfür entsprechende textile Standardmultifilamentgarne eingesetzt werden, die relativ preisgünstig sind. Auch weist das erfindungsgemäße Nähgarn überraschenderweise hervorragende Näheigenschaften auf, obwohl das Nähgarn lediglich textile Standardmultifilamentgarnen enthält. Diese hervorragenden Näheigenschaften drücken sich beispielsweise darin aus, daß das erfindungsgemäße Nähgarn selbst extreme Nähbelastungen standhält, so zum Beispiel bei einem multidirektionalen Nähen nicht reißt oder in sonstiger Weise den Nähprozeß störend beeinflußt. So konnte bei umfangreichen Nähversuchen festgestellt werden, daß selbst bei 7.000 Stichen pro Minute keine Störungen des Nähprozesses auftreten. Auch weist das erfindungsgemäße Nähgarn äußerst geringe Schrumpfeigenschaften auf, so daß ein Boldern von Nähten, die mit dem erfindungsgemäßen Nähgarn erstellt sind, nicht auftritt.The rotation coefficient α is defined as follows: $$\text{Rotation coefficient α =}\frac{\text{Turns per meter}}{\sqrt{\text{Nm}}}$$

The high-strength sewing thread according to the invention has a number of advantages. So it is relatively inexpensive to manufacture, because appropriate textile standard multifilament yarns are used for this, which are relatively inexpensive. The sewing thread according to the invention also surprisingly has excellent sewing properties, although the sewing thread only contains standard textile multifilament threads. These excellent sewing properties are expressed, for example, in the fact that the sewing thread according to the invention can withstand even extreme sewing loads, for example does not tear during multidirectional sewing or otherwise interfere with the sewing process. Extensive sewing trials have shown that even at 7,000 stitches per minute there are no disturbances in the sewing process. The sewing thread according to the invention also has extremely low shrinkage properties, so that bunching of seams which are produced with the sewing thread according to the invention does not occur.

With regard to the fiber substrates which the sewing thread according to the invention contains, it should be noted that here in principle all synthetic multifilament threads, for example polyamide 6, polyamide 6,6, polyalkylene or mixtures of the aforementioned threads, can be contained. However, it is particularly suitable if the textile standard multifilament yarns forming the thread are polyester yarns which have an intrinsic viscosity between 0.5 dl / g and 0.75 dl / g, in particular between 0.55 dl / g and 0.63 dl / g. The values of the intrinsic viscosity given above are a measure of the molecular structure of the multifilament yarns, these values being measured in dichloroacetic acid at 25 ° C.

Depending on the particular application of the sewing thread according to the invention, the overall titer of the sewing thread varies. The high-strength sewing thread according to the invention preferably has a total titer between 40 dtex and 3,900 dtex as finished sewing thread, a sewing thread with a correspondingly fine overall titer preferably in the area of the ready-made clothing, a sewing thread with a medium titer for example for shoes and a sewing thread with a coarse total titer for example is used in the area of technical textiles or heavy footwear.

Also depending on the respective field of application, the number of multifilament yarn components which are twisted together to form the sewing thread is determined in the high-strength sewing thread according to the invention. In this case, preferably two to four and in particular two or three multifilament yarn components are twisted with one another, but the high-strength sewing thread according to the invention can also contain more than four multifilament yarn components.

The number of filaments of the sewing thread according to the invention varies between 16 and 600 filaments, preferably between 24 and 200 filaments.

Regarding the single-filament titer, it should be noted that the high-strength sewing thread according to the invention has such multifilament thread components whose filaments have a single filament titer between 0.6 dtex and 10 dtex, preferably between 2.5 dtex and 5 dtex.

As already described at the beginning, the sewing thread according to the invention has excellent residual shrinkage values. It was thus found that the thermal shrinkage at 160 ° C. in hot air is less than 3%, preferably less than 2%, and the cooking shrinkage in water at approximately 98 ° C. is less than 2%, preferably less than 1%. As already explained above, this leads to the fact that the sewing thread according to the invention does not shrink or only shrinks slightly in the processed state with a corresponding thermal treatment, so that, for example, the assembled parts sewn with the sewing thread according to the invention as part of their manufacture or during later use of a corresponding thermal Treatment, for example steaming, hot air treatment or a boil, can be subjected without the seams becoming bold.

As already stated at the beginning, the present invention further relates to a method for producing the high-strength sewing thread described above, which is present as a thread. The process according to the invention for producing the high-strength sewing thread provides that a pre-oriented multifilament yarn (POY yarn) is selected for each multifilament yarn component forming the thread, the molecular structure of the pre-oriented multifilament yarn (POY yarn) corresponding to a textile standard multifilament yarn. These pre-oriented multifilament yarns are then drawn in such a way that their specific strength varies between 40 cN / tex and 85 cN / tex, preferably between 55 cN / tex and 75 cN / tex, so that the multifilament yarns drawn in this way are then formed together to form the yarn twisted, whereby a twist factor α between 70 and 140 is provided for the twist.

In other words, a relatively inexpensive starting material is used for the production of the high-strength sewing thread described above and the drawing conditions are varied in such a way that a high-strength filament yarn is produced from the relatively cheap starting material without it being necessary to use commercially available and use relatively expensive high-strength multifilament yarns.

The term molecular structure mentioned above means in particular the molecular weight, the molecular weight distribution and the chemical composition, ie the qualitative and quantitative proportions of the monomers forming the polymer.

The process according to the invention described above is characterized in particular by the advantage that it uses relatively inexpensive starting materials and produces high-strength multifilament yarns therefrom by varying the drawing conditions with a relatively low outlay on process engineering. These high-strength multifilament yarns are then twisted together to form the thread according to the invention, the resulting sewing thread then having the advantageous properties which are described in detail at the beginning of the sewing thread according to the invention. A sewing thread produced in this way can also be dyed relatively unproblematically and evenly, since, as already described above, it consists in principle of specially stretched standard textile multifilament yarns which do not differ significantly in their dyeing behavior from the standard textile multifilament threads.

A first embodiment of the method according to the invention provides that the pre-oriented multifilament yarns to be drawn, which in the stretched state are twisted to form the sewing thread according to the invention, are polyester-POY yarns. These polyester POY yarns have intrinsic viscosities that are between 0.5 dl / g and 0.75 dl / g, preferably between 0.55 dl / g and 0.63 dl / g. These polyester POY yarns are therefore yarns whose chemical structure and in particular their molecular weight correspond to conventional textile standard multifilament yarns. The intrinsic viscosities mentioned above represent such values represent, which are measured in corresponding solutions of the polymer in dichloroacetic acid at 25 ° C.

In a particularly suitable embodiment of the method according to the invention, each pre-oriented multifilament yarn is drawn in such a way that the multifilament yarn to be drawn is fed at a first speed to a main drawing zone via a delivery godet wrapped in the yarn. The multifilament yarn is withdrawn from the main stretching zone at a second speed by means of a take-off godet wrapped around a multifilament yarn to be drawn, the second speed being 70% to 180%, preferably 100% to 160%, greater than the first speed. In this embodiment of the method according to the invention, the take-off godet is heated to a temperature between 160 ° C. and 240 ° C. Due to the previously described speed differences between the first speed and the second speed, a degree of stretching of 1: 1.7 to 1: 2.8, preferably 1: 2, is thus in the main stretching zone, which is formed exclusively from the delivery godet and the take-off godet , 0 to 1: 2.6. Although these degrees of stretching are very high, surprisingly no filament breaks occur during such stretching, so that this stretching process is particularly insusceptible to faults. Furthermore, the tensile strengths of a multifilament yarn stretched in this way are extremely high, ie they are in the range between 40 cN / tex and 85 cN / tex depending on the pre-oriented multifilament yarn (POY yarn) used in each case.

A further development of the previously described embodiment variant of the method according to the invention provides that the delivery godet is also heated to a temperature between 60 ° C. and 160 ° C., preferably to a temperature between 80 ° C. and 140 ° C.

In a further variant of the inventive method described above, heating is carried out in the main stretching zone, i.e. between the delivery godet and the take-off godet, the multifilament yarn to be drawn to a temperature between 80 ° C and 180 ° C. This heating of the multifilament yarn (POY yarn) to be drawn is preferably carried out in the main drawing zone in such a way that in particular a hot plate, an IR emitter and / or a laser is used for this purpose.

Regarding the time at which the multifilament yarn to be drawn is heated in the main drawing zone and allowed to dwell at the aforementioned temperatures (80 ° C. to 180 ° C.), it should be noted that this residence time varies in particular between 0.01 s and 1 s.

In order to obtain the clamping points required for drawing in the main drawing zone in the previously described embodiments of the method according to the invention, the delivery godet and the take-off godet are looped around with the multifilament yarn to be drawn, as already described above. Here it has been shown that especially then High strengths and particularly low shrinkage values of the stretched multifilament yarn result when the delivery godet and / or the take-off godet is wrapped 5 to 40 times, preferably 10 to 20 times, with the multifilament yarn to be stretched. These wrapping values relate to godets whose diameters vary between approximately 40 mm and 250 mm, preferably 80 mm and 120 mm.

Another, particularly suitable development of the previously described embodiment variants of the method according to the invention provides that a pre-stretching zone is arranged in front of the main stretching zone, viewed in the transport direction of the multifilament yarn to be stretched. In other words, the multifilament yarn (POY yarn) to be drawn is first partially drawn in the pre-drawing zone and then finally drawn in the main drawing zone.

In the development of the method according to the invention described above, it is advisable to pre-stretch the pre-oriented multifilament yarn in the pre-stretching zone between 0.5% and 10%, preferably between 1% and 4%. the pre-oriented multifilament yarn, which is preferably a polyester POY yarn, is thus lengthened in the pre-stretching zone between 0.5% and 10%, preferably between 1% and 4%.

Regarding the pre-stretching or stretching speeds, it should be noted that one is then particularly economical and reproducibly achieves the aforementioned high strengths and low shrinkage values if one selects take-off speeds that are greater than 300 m / min and are preferably between 600 m / min and 1,200 m / min.

In order to produce a particularly low-shrinkage and drawn yarn by means of the drawing process described above, another, particularly suitable development of the above-described process provides that, viewed in the direction of transport of the multifilament yarn, a relaxation zone is arranged behind the main drawing zone, in which the drawn multifilament yarn is heated to a temperature between 80 ° C and 240 ° C, preferably to a temperature between 140 ° C and 200 ° C, is heated. It has been shown here that such a relaxation zone further reduces the shrinkage values, in particular the cooking shrinkage value (water 98 ° C.) and the hot air shrinkage value (160 ° C.) of the drawn multifilament yarn. This is particularly true when the drawn multifilament yarn is introduced into the relaxation zone with lead, which is preferably between 0.5% and 10% and in particular between 1% and 3%.

The residence time of the multifilament yarn in the relaxation zone then varies depending on the respective transport speed of the yarn through the relaxation zone and is preferably 0.01 s to 1 s.

The selection of the multifilament yarn (POY yarns) used in the method according to the invention depends on the later use of the drawn yarn. Such multifilament yarns are preferably selected here whose single filament titer varies between 1 dtex and 26 dtex, preferably between 4 dtex and 10 dtex.

The total titer of the POY yarn to be drawn in each case also depends on the later use of the sewing thread produced therefrom. This total titer of the POY yarn usually varies between 40 dtex and 2,000 dtex, preferably between 80 dtex and 1,200 dtex, so that after drawing and twisting two multifilament yarns drawn in this way, a sewing thread results, the total titer of which is between 40 dtex and 2,600 dtex, preferably is between 80 dtex and 1,300 dtex. If, on the other hand, three multifilament yarns stretched in this way are twisted to form the sewing thread, the total titer of the sewing thread varies between 120 dtex and 3,900 dtex, preferably between 240 dtex and 1,800 dtex.

Regarding the number of filaments of the multifilament yarn to be drawn, it should be noted that this varies between 8 and 300, preferably between 24 and 100.

After the multifilament yarns forming the high-strength sewing thread according to the invention have thus been stretched in the manner described above, these multifilament yarns are then subsequently twisted with one another in the method according to the invention to form the sewing thread.

A particularly suitable embodiment of the method according to the invention provides that each individual multifilament yarn is twisted before twisting. In other words, in this embodiment, each multifilament yarn is thus pre-twisted before the pre-twisted multifilament yarns are twisted out to form the sewing thread. In this case, a yarn twist has proven to be particularly suitable for this pre-twisting, the twist coefficient α of which varies between 80 and 110, wherein in particular each individual multifilament yarn is provided with an S yarn twist.

With regard to the twisting of the pre-twisted multifilament yarns, it should then be noted that preferably a Z-twist twist is provided which has a twist coefficient α between 70 and 140, as already described above.

A sewing thread according to the invention, which consists entirely of polyester multifilaments, has particularly good results with regard to the sewing behavior. Accordingly, polyester multifilament yarns are preferably also used as the starting material for producing the sewing thread according to the invention in the method according to the invention, polyester being understood as meaning polyethylene terephthalate in the sense of the present application.

Advantageous developments of the high-strength sewing thread according to the invention and of the method according to the invention are specified in the subclaims.

The method according to the invention is explained in more detail below using exemplary embodiments in conjunction with the drawing. The single figure of the drawing shows a schematic view of a stretching device.

Three pre-oriented multifilament yarns (POY yarn) A, B and C are transported in the direction of arrow 13 on a system shown in the figure. The yarns A, B and C are drawn off from cones, not shown. The yarns drawn off in this way are then fed to a delivery unit 7, 8 or 9. The yarns A, B and C are fed from the delivery unit 7 or 8 or 9 to a delivery godet 1 or 3 or 5, the yarns A, B or C in each case between the delivery unit 7 and the delivery godet 1, the Delivery unit 8 and the delivery godet 3 or the delivery unit 9 and the delivery godet 5 are pre-stretched. Delivery godets 1, 3 and 5 are each heated to 110 ° C. The supply godet 1 and the take-off godet 2 form the main stretch zone for the yarn A, the delivery godet 3 and the take-off godet 4 form the main draw zone for the yarn B, and the delivery godet 5 and the take-off godet 6 form the main draw zone for the yarn C. Discharge godets 2, 4 and 6 are heated to a temperature of 180 ° C. In the main drawing zones, each yarn (A, B or C) is drawn at an adjustable drawing level. The drawn multifilament yarns A, B and C then enter a thermal relaxation zone 10, in which yarns A, B and C are each heated to a temperature of 180 ° C. for 0.05 s. The yarns A, B and C are introduced into the thermal relaxation zone 10 via the delivery devices 14, the lead is 2%. The three drawn yarns are wound up at the outlet of the relaxation zone 10. The godets 1 - 6 have a diameter of 150 mm and are wrapped in the yarn 20 times.

The speed of drawing was 800 m / min for the two examples described below.

The wound yarns are fed to a schematically drawn pre-twisting device 11, in which each yarn A, B or C is pre-twisted with a twist factor α of 100 (yarn twist S). The pre-twisted multifilament yarns A, B and C then arrive at a twisting device 12, in which they are twisted out with the formation of the sewing thread (twist twist Z) with a twist factor α of 90.

On the system described above, two sewing threads were produced, which are referred to below as sewing thread I and sewing thread II.

Three POY multifilament yarns served as the starting material for the sewing thread I, each yarn having a titer of 410 dtex and a single filament count of 40. These yarns were drawn at a draw ratio of 1: 2.4 in the main draw zone and pre-drawn at 5% in the pre-draw zone. The sewing thread obtained after twisting had a total titer of 460 dtex and a total number of filaments of 120. The twist factor α of the sewing thread was 100.

The strength of the sewing thread I was 65 cN / tex. The sewing thread I had a thermal shrinkage at 160 ° C. of 1.2% and a boiling shrinkage (water 98 ° C.) of 0.8%. Examination of the sewing behavior of the sewing thread I showed that the sewing thread I did not tear when multidirectional sewing was carried out at 7,000 stitches per minute.

Three pre-oriented multifilament yarns were used as the starting material for the sewing thread II, which had a titer of 301 dtex and a single filament number of 30 as the starting material. These three multifilament yarns were first pre-drawn at 4% on the system described above and then drawn in the main drawing zone at a drawing ratio of 1: 2.5. These three starting materials were then pre-twisted with a twist factor of 90 and were then twisted out with a twist factor α of 110. The sewing thread II thus produced had a tenacity of 70 cN / tex, a thermal shrinkage value (hot air 160 ° C.) of 1% and a boiling shrinkage value (water 98 ° C.) of 0.7%. The total titer of sewing thread II was 325 dtex and its single filament count was 90.

Examination of the sewing behavior of sewing thread II showed that sewing thread II did not tear when multidirectionally sewing at 7,000 stitches per minute.

Claims (29)

1. A sewing yarn with a high strength, comprising at least two multifile yarn components and having a specific strength of between 40 cN/tex and 85 cN/tex, preferably between 55 cN/tex and 75 cN/tex, characterized in that the sewing yarn has the construction of a plied sewing yarn and that it comprises at least two yarn components being twisted around each other, that the yarn components forming the plied sewing yarn are textile standard multifilament yarns and that the plied sewing yarn has a twisting factor alpha of between 70 and 140.
2. The sewing yarn according to claim 1, characterized in that the textile standard multifilament yarns are polyesteryarns and that they have an intrinsic viscosity of between 0,5 dl/g and 0,75 dl/g, preferably between 0,55 dl/g and 0,63 dl/g.
3. The sewing yarn according to one of the preceding claims, characterized in that the plied sewing yarn has a total titre of between 40 dtex and 3.900 dtex.
4. The sewing yarn according to one of the preceding claims, characterized in that the plied sewing yarn comprises two to four multifile yarn components.
5. The sewing yarn according to one of the preceding claims, characterized in that the plied sewing yarn has a filament number of between 16 and 600, preferably between 24 and 200.
6. The sewing yarn according to one of the preceding claims, characterized in that the single filament titre of the plied sewing yarn varies between 0,6 dtex and 10 dtex, preferably between 2,5 dtex and 5 dtex.
7. The sewing yarn according to one of the preceding claims, characterized in that the plied sewing yarn has a thermal shrinking at 160 °C being smaller than 3 %, preferably smaller than 2 %.
8. The sewing yarn according to one of the preceding claims, characterized in that the plied sewing yarn shows a shrinking by boiling being smaller than 2 %, preferably smaller than 1 %.
9. A method for the manufacturing of the sewing yarn having a high strength according to one of the preceding claims, characterized in that the sewing yarn is constructed as a plied sewing yarn, that for each multifile yarn component forming the plied sewing yarn a preorientated multifilament yarn (POY-yarn) is chosen, whereby the preorientated multifilament yarn (POY-yarn) corresponds concerning its molecular structure to a textile standard multifilament yarn, and that the preorientated multifilament yarn is drawn in such a way that its specific strength lays between 40 cN/tex and 85 cN/tex, preferably between 55 cN/tex and 75 cN/tex and that subsequently the drawn multifilament yarns are twisted around each other under the formation of the plied sewing yarn, whereby for the ply twist a twisting factor alpha of between 70 and 140 is intended.
10. The method according to claim 9, characterized in that polyester-POY-yarns are chosen as preorientated multifilament yarn having an intrinsic viscosity of between 0,5 dl/g and 0,75 dl/g, preferably between 0,55 dl/g and 0,63 dl/g.
11. The method according to one of the claims 9 or 10, characterized in that each preorientated multifilament yarn forming the plied yarn is drawn in such a way, that the preorientated multifilament yarn is entered into a main drawing zone at a first speed over a delivery godet roll wrapped by the multifilament yarn and is drawn off from the main drawing zone at a second speed over a detaching godet roll wrapped by the multifilament yarn, whereby the second speed is 70 % to 180 %, preferably 100 % to 160 %, faster than the first speed, that the drawing in the main drawing zone is carried out exclusively between the delivery godet roll and that the detaching godet roll and the detaching godet roll is heated up to a temperature of between 160 °C and 240 °C.
12. The method according to claim 11, characterized in that the delivery godet roll is heated up to a temperature of between 60 °C and 160 °C, preferably to a temperature of between 80 °C and 140 °C.
13. The method according to claim 11 or 12, characterized in that the multifilament yarn to be drawn is heated up to a temperature of between 80 °C and 180 °C in the main drawing zone.
14. The method according to claim 13, characterized in that for the heating of the multifilament yarn in the main drawing zone a hot plate, an infrared radiator and/or a laser is used.
15. The method according to claim 13 or 14, characterized in that the multifilament yarn to be drawn is heated up in the main drawing zone for 0,01 s and 1 s.
16. The method according to one of the preceding claims, characterized in that the delivery godet roll and/or the detaching godet roll is wrapped with the multifilament yarn to be drawn for 5 to 40 times, preferably for 10 to 20 times.
17. The method according to one of the claims 11 to 16, characterized in that a pre-drawing zone is arranged in transport direction of the multifilament yarn before the main drawing zone.
18. The method according to claim 17, characterized in that in the pre-drawing zone the multifilament yarn is pre-drawn between 0,5 % and 10 %, preferably between 1 % and 4 %.
19. The method according to one of the claims 11 to 18, characterized in that the pre-drawing and/or the drawing is carried out at a drawing off speed being faster than 300 m/min, preferably at a speed of between 600 m/min and 1.200 m/min.
20. The method according to one of the claims 11 to 19, characterized in that a relaxation zone is arranged in transport direction of the multifilament yarn to be drawn behind the main drawing zone, whereby in this relaxation zone the drawn multifilament yarn is heated up to a temperature of between 80 °C and 240 °C, preferably to a temperature of between 140 °C and 200 °C.
21. The method according to claim 20, characterized in that the drawn multifilament yarn is delivered into the relaxation zone with an overfeed.
22. The method according to claim 21, characterized in that the drawn multifilament yarn is delivered into the relaxation zone with an overfeed of between 0,5 % and 10 %, preferably to 1 % and 3 %.
23. The method according to one of the claims 9 to 22, characterized in that such a yarn is chosen as preorientated multifilament yarn that has a single filament titre of between 1 dtex and 25 dtex, preferably between 4 dtex and 10 dtex.
24. The method according to one of the claims 9 to 23, characterized in that the POY-yarn to be drawn has a total titre of between 40 dtex and 2.000 dtex, preferably between 80 dtex and 1.200 dtex.
25. The method according to one of the claims 9 to 24, characterized in that the POY-yarn to be drawn has an elementary thread number of between 8 and 300, preferably between 24 and 100.
26. The method according to one of the claims 9 to 25, characterized in that each multifilament yarn is provided with a yarn twist before the twisting of the drawn multifilament yarns.
27. The method according to claim 26, characterized in that for the yarn twist a twisting factor alpha of between 80 and 110 is chosen.
28. The method according to claim 26 or 27, characterized in that each drawn multifilament yarns is provided with a S-yarn twist.
29. The method according to claim 9, characterized in that the ply twist is a Z-ply twist.

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