EP1103641A1 - Method of false twisting a synthetic yarn to make a crimped yarn - Google Patents

Abstract

False twisting action on synthetic filaments, feeds filaments at given speed and low absolute tension of max. 5 cN to heated drawing pin at drawing zone. Filaments pass around drawing pin with angle ( alpha ) of ≤ 270 degrees , and are drawn out of drawing zone with higher filament tension than before drawing. The false twisting action on synthetic filaments, for use as a texturized yarn, feeds the filaments at a given speed and a low absolute tension of max. 5 cN to a heated drawing pin at a drawing zone. The filaments pass around the drawing pin with an angle (alpha) of at most270degrees, and are drawn out of the drawing zone with a significantly higher filament tension than before drawing. The filaments are passed into a false twisting zone at a higher speed than the original delivery speed, to be heated to a temp. of at least180degreesC and then cooled with a false twist, within the false twisting zone, with a false twister to give the filaments a false twist. The filaments are drawn from the false twisting zone at a speed of at least400 m/min. to give the filaments an additional drawing action. The filaments are wound on to a bobbin. The filament tension in front of the feed to the take-off from the drawing zone is 0.5-1.2 cN/dtex. The drawing pin temp. is 80-160 degrees C and pref. ≥ 100 degrees C, and the filaments pass around the pin with an angle of at least 90 degrees . For the initial drawing action in the drawing zone, the speed ratio in the filament travel between its feed (w1) and delivery (w1.1) speeds is set at w1 divided by w1.1 ≥ 1.4 and pref. w1 divided by w1.1=1.5-1.7. For the final drawing action in the false twisting zone the speed ratio between the take-off speed (w2) and the feed speed (w1) is set at w2 divided by w1=1.03-1.06. The filaments are given a false twist by a number of friction disks. The false twisted yarns are given a finishing heat treatment before bobbin winding. An Independent claim is included for a texturized yarn where the synthetic filaments are looped together irregularly to give alternating zones where they are bonded together and where they are loose. The loose zones have a larger yarn cross section than the bonded zones. Preferred Features: The alternating zones have an irregular sequence and size, with zone lengths from a few mm to several cm. The yarn is composed of at least two filaments. At least one filament has been false twisted before they are combined into the texturized yarn. Or the filaments are combined directly after they have been drawn from their supply point, and the bonded filaments pass together through the drawing and false twisting stages. The filaments are combined by an air eddy action within an eddy jet, directly after the false twisting stage. A further Independent claim is included for false twisting synthetic filaments (4), with a feed unit (17) which draws them off a supply bobbin (1). A heated drawing pin (18) is at the drawing zone, in the filament path after the feed unit (17), with a drawing zone feed (2). The assembly has a heater (5), a cooling unit (6), a false twister (7) with a second feed unit (3), and a bobbin winder (10). A filament guide (19) is in the movement path after the drawing pin (18), to set the angle of filament (4) travel around the drawing pin (18). Preferred Features: The filament guide (19) has an adjustable position within a guide path (20), which describes an arc around the drawing pin (18) at a constant gap from it.

Description

The invention relates to a method for false twist texturing of a synthetic Thread to a crimp yarn and the crimp yarn.

To the properties of artificial textile threads that of threads from natural It is known to blend fibers such as wool or cotton, which are spun to refine synthetic threads in a texturing process. The synthetic filament strands that form the thread, crimped so that the thread has a more textile appearance and the associated properties. Such a method is known for example from JP 05311527 A. Here, the multifilament thread is heated in a drawing zone with the help of a Stretching pin stretched and then textured in a false twist zone. For Generation of the crimp creates a false twist in the thread, which in the False twist zone is fixed by means of a heating device. Then the crimped thread wound into a bobbin.

In the known method, a curling yarn is produced, which is a very uniform structure with a low bulk. By hot stretching the filaments on the drawing pin become a relatively closed filament composite created a low bulk and thus a low fullness of Curled gams. The crimped yarns produced in this way receive a more artificial look.

It is an object of the invention, the method mentioned at the outset To further develop false twist texturing in such a way that a crimped yarn is produced, the fullness, feel and appearance of the character of natural fibers comes as close as possible.

The object is achieved according to the invention by a method with the features Claim 1 and a crimped yarn with the features of claim 8 solved.

The method according to the invention is based on the finding that the setting the thread tension in the drawing zone in front of the drawing pin an immediate Influences the uniformity of the stretching. So it was found that with particularly low thread tensile forces the thread during the run-up on the stylus is excited to vibrate, which leads to an uneven thermal stress on the thread on the drawing pin and thus to an uneven Stretching the thread leads. Here, the effects are used, that the evaporating volatile constituents of the thread on emergence exert forces on the hot straightening pin which are proportional to the low thread tension acting transversely to the thread running direction and a swinging movement of the thread on the drawing pin. The uneven stretching and uneven thermal stress on the thread has an effect the false twist texturing in the false twist zone such that the synthetic Filaments are so unevenly intertwined that they alternate Thread pieces with a loose filament waistband and thread pieces with a closed filament waistband are present. The loose filament band forms a larger thread cross-section than the fixed filament bundle, so that a Crimp yarn with a thick-thin effect is created.

In the false twist texturing method according to the invention, the synthetic thread is fed to a heated stretching pin in a stretching zone with a delivery speed w _1.1 and a low absolute thread tension F ₁ of at most 5 cN. The thread is drawn in the drawing zone by wrapping the drawing pin with a wrap angle α <270 ° and drawn off by a downstream delivery mechanism, the thread tension F ₂ in the thread path behind the drawing pin being significantly greater than the thread tension F _{1 in} front of the drawing pin. The thread is fed into the false twist zone by the feed mechanism at a feed speed w ₁ , the feed speed w _{1 being} greater than the delivery speed w _1.1 for stretching the thread in the draw zone. In the false twist zone, the false twist is fixed at a temperature of over 180 ° C. The thread is then slightly stretched in the false twist zone, but the take-off speed w ₂ is not greater than 1.1 times the feed speed w ₁ . The crimped yarn is then wound up into a bobbin.

In order to produce the change in the filament composite in the crimped yarn reproducibly, the method variant according to claim 2 has proven particularly useful. Here, the thread tension F ₂ is set in the range from 0.5 cN / dtex to 1.2 cN / dtex in front of the delivery mechanism for pulling the thread out of the drawing zone.

The drawing pin is in the range when the thread is stretched to a temperature heated from 80 ° C to 160 ° C, preferably above 100 ° C, the thread Wrapping pin partially wrapped with a wrap angle in the range of at least 90 °. This has an influence on the crystallinity of the filament strands, so that the differences in the filament composites have a high stability.

To even out the stretching, post-stretching is carried out in the false twist zone of the thread. Here is the setting of post-stretching according to the method variant according to claim 5 particularly advantageous.

To ensure that the filament strands in the thread pieces with a closed filament waistband has received sufficient crimp to generate the false twist on the thread especially a false twist proven several friction discs.

The process variant is used to produce less highly elastic crimp yarns proposed according to claim 7. Here the thread after the False twist generation and before winding to the coil by heating post-treated so that the thread can shrink.

The process according to the invention enables the production of a crimped yarn possible, which has properties that are otherwise only known from fancy yarns are. The natural character of the crimped yarn according to the invention becomes due to the irregular changes in the sequence and size of the filament bundles particularly reinforced. The uneven thread cross section of the invention Crimped yarn occurs especially when dyeing the filament yarn or even stronger with a fabric made from it forth. Not only that the thread pieces with the open filament band one have completely different color rendering than the thread pieces with closed Filamentbund, but have the thread pieces with closed filament bundle also a higher crystallinity than the thread pieces with an open filament band. A structured dyeability is thus achieved, that in a flat structure leads to a uniform color structure. The different pieces of thread can range from a few millimeters to several centimeters have.

Such crimped yarns can be opened with a filament waistband due to the thread pieces advantageous to a composite thread from several individual threads produce different polymers, for example. This is the procedure proposed according to claim 11. At least one of the threads is in front of the Connecting to the composite thread according to the invention textured according to the method steps according to claim 1. The composite threads thus produced stand out also characterized by a natural character. The threads are connected preferably by air swirling using a swirling nozzle. there an air jet is directed essentially across the bundle of threads, so that intertwine the filaments of the threads.

The device has been used to produce the crimped yarn according to the invention with the features according to claim 14 particularly proven. The Device a supplying plant, a drawing pin, a first supplying plant, a heating device, a cooling device, a false twister, a second delivery plant and a winder. According to the invention is a thread guide in Thread run downstream of the straightening pin, which for setting a predetermined The wrap angle of the thread is designed to be adjustable on the stretching pin is. This allows the characteristic uneven stretching on Drawing pin by changing the wrap of the thread within wide limits to adjust.

The thread guide is preferably adjusted on a guideway with a is formed substantially constant distance from the circumference of the stretching pin.

The thread tension forces set in the drawing zone thus remain essentially unchanged even when changing the wrap angle on the stretching pin.

The method according to the invention and the crimped yarn according to the invention are described in more detail below with reference to the accompanying drawings.

Fig. 1

ein erstes Ausführungsbeispiel einer Vorrichtung zur Durchführung des erfindungsgemäßen Verfahrens;

Fig. 2

schematisch eine Ansicht des Kräuselgarns;

Fig. 3

ein Ausführungsbeispiel einer Vorrichtung zur Herstellung eines Verbundfadens mit dem erfindungsgemäßen Verfahren.

They represent:

Fig. 1

a first embodiment of an apparatus for performing the method according to the invention;

Fig. 2

schematically a view of the crimp yarn;

Fig. 3

an embodiment of an apparatus for producing a composite thread with the inventive method.

In Fig. 1 an embodiment of the device according to the invention for performing the method according to the invention is shown schematically. The device has a feed unit 17 which draws a multifilament thread 4 from a supply spool 1 via a head thread guide 15. The feed unit 17 is driven in such a way that the thread 4 is guided into a drawing zone at a delivery speed w _1.1 . A heated stretching pin 18 is arranged within the stretching zone, which extends between the supply unit 17 and a downstream supply unit 2. The stretching pin 18 is heated to a surface temperature in the range from 80 ° C to 160 ° C. The stretching pin 18 is wrapped by the thread 4 with a wrap angle in the range of at least 90 °. Here, a thread guide 19 is arranged on the outlet side of the stretching pin 18. The thread guide 19 can be adjusted in a guide 20 essentially parallel to the stretching pin in such a way that a wrap angle α of 90 ° to 270 ° can be set on the stretching pin. After setting a wrap angle, the thread guide 19 is fixed in its respective position, so that the thread wrap on the stretching pin remains unchanged during the process.

The thread 4 is withdrawn from the drawing zone by the feed mechanism 2 connected downstream of the thread guide 19 and is guided into a false twist zone which extends between the feed mechanism 2 and a false twister 7. A false twist is generated on the thread 4 by the false twister 7. The false twist sensor 7 is designed as a friction disk unit, in which a plurality of disks are arranged on three axes in such a way that the disks overlap in a central region which the thread traverses. The friction disks have a circumferential speed which is approximately twice a withdrawal speed w ₂ from the false twist zone. A heating device 5 and a cooling device 6 are arranged within the false twist zone. A thread guide 9 is provided between the heating device 5 and the cooling device 6. The heating device 5 is designed such that the thread is heated to a temperature in the range from 180 to 200 ° C. For this purpose, the heating device can have a heat transfer fluid which heats a heating surface contacted by the thread. However, it is also possible for the heating device to be electrically heated at a temperature above the melt temperature of the thread material. In this case, the thread is guided at a distance from the heating surface.

The heating device 5 is followed by the cooling device 6, by means of which the thread is cooled to a temperature of approximately 80 to 100 ° C. The cooled thread passes through the false twist sensor 7. The thread 4 is then drawn out of the false twist zone by the second delivery mechanism 3 at a take-off speed w ₂ . However, the post-stretching in the false twist zone is limited and does not go beyond the speed ratio between the take-off speed and the feed speed of w ₂ / w ₁ = 1.1 and is preferably in the range of w ₂ / w ₁ = 1.03 to 1.06 .

The thread could be used to produce a highly elastic crimp yarn after the second delivery mechanism 3 to a spool in a winding device 10 be wound up. In the device shown in Fig. 1 is an aftertreatment of the thread 4 provided. For this purpose, the second delivery unit 3 is a second heater 8 connected downstream. The thread is received in the heating device 8 post-heat treatment for tension compensation or shrinking treatment. The thread 4 is from the third delivery unit 14 from the heating device 8 deducted and after preparation in a preparation device 11 a coil wound in the winder 10. For this purpose, the coil 12 driven by a drive roller 13 at a uniform peripheral speed. The bobbin 12 contains the crimped yarn according to the invention.

In the manufacture of the crimped yarn, the thread guide in the drawing zone between the supply unit 17 and the first supply unit 2 is set such that in the thread section between the supply unit 17 and the drawing pin 18 a very low thread tension F ₁ , which is in the range below 5 cN , set. In contrast, the full thread tension, which is in the range from 0.5 cN / dtex to 1.2 cN / dtex, acts in the thread piece between the adjustable thread guide 19 and the first delivery mechanism 2. This setting according to the invention achieves uneven drawing and thermal stress on the thread 4 on the drawing pin 18. The delivery speed w ₁ is set to the delivery speed w _1.1 in the ratio w ₁ / w _1.1 = 1.5 to 1.7, so that the thread 4 is stretched. In the false twist zone, there is a slight post-stretching while the crimp is fixed. For this purpose, the take-off speed w _{2 of} the second delivery unit 3 is set to be slightly higher than the delivery speed w _{1 of} the first delivery unit. The speed ratio here is preferably at w ₂ / w ₁ = 1.03 to 1.06. The method according to the invention is suitable for producing highly elastic yarns or set yarns from polyester, polyamide or polypropylene. Spun POY yarns in the range from 50 to 200 dtex with 1.5 to 5 dpf can be presented.

2 shows a view of a crimped yarn according to the invention. The crimped yarn is formed by a variety of filaments. The synthetic filaments are unevenly intertwined with respect to the length of the thread, so that there are alternately open and closed thread cross sections which are formed due to differences in crystallinity in the filament strands after the false twist texturing. The thread cross sections are identified in Fig. 2 with the designations d ₁ , d ₂ and d ₃ . The associated thread pieces are entered with the lengths L ₁ , L ₂ and L ₃ in Fig. 2. The filaments in the section L ₁ form a relatively open filament bundle with the thread cross section d ₁ . In the adjacent piece of thread L ₂ , the filaments are intertwined to form a closed bundle of filaments with the smaller thread cross section d ₂ . This change is repeated so that the thread piece L ₃ adjacent to the thread piece L _{2 has} a relatively open filament bundle with the thread cross section d3. The thread pieces L ₁ , L ₂ and L ₃ can extend over a distance of a few millimeters up to several centimeters depending on the setting of the thread tension, the wrap angle on the stretching pin, the thread speeds and the temperature settings on the stretching pin and in the heating device . The size of the thread cross sections and the length distribution are irregular, so that the crimped yarn has an uneven surface structure, which is comparable to a thick-thin effect yarn. The crimped yarn according to the invention is therefore particularly suitable for producing flat structures with color structures.

In Figure 3 is an embodiment of an apparatus for producing a Composite thread shown schematically by the inventive method. The device is essentially identical to the device shown in FIG. In this respect, reference is made to the preceding description and only the differences of the device according to FIG. 3 are described at this point.

In the device shown in Figure 3, two threads 4.1 and 4.2 of one supply spool 1.1 and 1.2 each are subtracted by the supply unit 17. The Threads 4.1 and 4.2 are guided in parallel in a stretching zone. Within the stretch zone, the threads 4.1 and 4.2 are heated by means of a Stretching pin 18 stretched. For setting the wrap angle of the threads a thread guide 19 is arranged on the stretching pin 18 behind the stretching pin 18, which is adjustable essentially parallel to the stretching pin within a guide 20 is. The threads 4.1 and 4.2 are made by a subordinate delivery unit 2 withdrawn from the stretching zone and led into a false twist zone. The false twist zone contains a heating device 5, a cooling device 6 and a false twist unit 7. Here, the units in the false twist zone are double units formed so that the threads 4.1 and 4.2 are textured in parallel side by side. The threads 4.1 and 4.2 are then from a False twist zone subtracted. Then the threads 4.1 and 4.2 together connected to a composite thread 22. For this purpose, the threads 4.1 and 4.2 led into a swirling nozzle 21 and with a substantially transverse directed air pressure.

The composite thread is fed by a delivery unit arranged downstream of the intermingling nozzle 21 3.2 led into a post-treatment zone. The composite thread 22 heated within a heating device 8 in order to compensate for such internal stresses. The composite thread 22 is from a further delivery unit 14 from the Heating device 8 deducted and after preparation in a preparation device 11 wound into a coil 12 in a winding device 10.

The thread guide for stretching and false twist texturing is here identical to the device described in Figure 1. In this regard, the procedural steps and unit settings of Figure 3 to the previous description referred to Figure 1.

In contrast to the previous embodiment, the device 3 suitable for texturing several threads simultaneously and then to merge into a composite thread. The number of threads in Figure 3 is an example. There is also the possibility of a composite thread so that one of the threads directly into the false twist zone to be led. This situation is shown in dashed lines in FIG. Here the Thread 4.2 is withdrawn from the supply spool 1.2 by the delivery unit (2) and in the false twist zone led. The second thread 4.1, however, is before texturing performed in the stretch zone.

A composite thread produced in this way has a relatively low thick-thin effect on.

Reference list

1

Supply spool

2nd

Delivery plant

3rd

Delivery plant

4th

thread

5

Heating device

6

Cooling device

7

False twister

8th

Heating device

9

Thread guide

10th

Take-up device

11

Preparation device

12th

Kitchen sink

13

Drive roller

14

Delivery plant

15

Head thread guide

16

Filaments

17th

Supplier plant

18th

Drawing pin

19th

Thread guide

20th

guide

21

Swirl nozzle

22

Composite thread

Claims (15)

Method for false twist texturing of a synthetic thread in the following steps: 1.1. Delivery of the thread with a delivery speed w _1.1 and a low absolute thread tension F ₁ of maximum 5 cN to a heated drawing pin in a drawing zone; 1.2. Stretching the thread by wrapping the stretching pin with a wrap angle α <270 ° and pulling off the thread with a thread tension F ₂ which is significantly greater than the thread tension F _{1 in} front of the stretching pin; 1.3. Feeding the thread into a false twist zone with a feed speed w ₁ that is greater than the delivery speed w _1.1; 1.4. Heating the thread with false twist to a temperature T> 180 ° C. and then cooling the thread with false twist within the false twist zone; 1.5. Dissolving the false twist on the thread by a false twister; 1.6. Pulling the thread out of the false twist zone at a take-off speed w ₂ which is above 400 m / min, which, in order to stretch the thread in the false twist zone, is not greater than 1.1 times the feed speed w ₁ , i.e. 400 m / min <w2 <1.1 * w ₁ and 1.7. Winding the thread into a bobbin. Method according to claim 1,
characterized in that
the thread tension F _{2 in} front of the delivery mechanism for pulling the thread out of the drawing zone is in the range from 0.5 cN / dtex to 1.2 cN / dtex. The method of claim 1 or 2,
characterized in that
the stretching pin is heated to a temperature in the range from 80 ° C. to 160 ° C., preferably above 100 ° C., and that the thread partially wraps around the stretching pin with a wrap angle in the range of at least 90 °. Method according to one of claims 1 to 3,
characterized in that
to pre-stretch the thread in the drawing zone, a speed ratio between the feed speed w ₁ and the delivery speed w _1.1 of w ₁ / w _1.1 > 1.4, preferably w ₁ / w _1.1 1, 5-1.7 is set. Method according to one of the preceding claims,
characterized in that
to redraw the thread in the false twist zone, the speed ratio between the take-off speed w ₂ and the feed speed w _{1 is set} in the range from w ₂ / w ₁ = 1.03-1.06. Method according to one of the preceding claims,
characterized in that
the false twist on the thread is generated by a false twister with several friction disks. Method according to one of claims 1 to 6,
characterized in that
the thread receives a post-treatment by heating after the false twist generation and before winding up to the bobbin. Crimped yarn consisting of a large number of synthetic filaments, which is produced by drawing, heating and false twist texturing,
characterized in that
the synthetic filaments are so unevenly intertwined that there are alternately thread pieces with an open filament composite and thread pieces with a closed filament composite, the open filament composite having a larger thread cross section than the closed filament composite. Crimp yarn according to claim 8,
characterized in that
the change in the thread pieces in their sequence and size occur irregularly, and that the thread pieces have a length of a few millimeters up to several centimeters. Curling yarn according to claim 8 or 9,
characterized in that
the filament composites can be produced by the following steps: 10.1. Delivering the thread with a delivery speed w _1.1 and a low absolute thread tension F ₁ of maximum 5 cN to a heated stretching pin in a stretching zone; 10.2. Stretching the thread by wrapping the stretching pin with a wrap angle α <270 ° and pulling off the thread with a thread tension F ₂ which is significantly greater than the thread tension F _{1 in} front of the stretching pin; 10.3. Feeding the thread into a false twist zone with a feed speed w ₁ which is greater than the delivery speed w _1.1; 10.4. Heating the thread with false twist to a temperature T> 180 ° C and then cooling the thread with false twist within the false twist zone; 10.5. Dissolving the false twist on the thread by a false twister and 10.6. Pulling the thread out of the false twist zone at a take-off speed w ₂ which is above 400 m / min, which, for further stretching of the thread in the false twist zone, is not greater than 1.1 times the feed speed w ₁ , that is 400 m / min <w ₂ < 1.1 * w ₁ . Method for producing a composite thread, which is made up of at least two Threads are formed, with at least one of the threads before connecting false twist textured according to the method of one of claims 1 to 7 becomes. The method of claim 11
characterized in that
the threads are brought together immediately after each take-off from a supply spool and are false-twist textured together before the connection according to the method of one of claims 1 to 7. The method of claim 11 or 12,
characterized in that
the threads are connected by air swirling within a swirl nozzle immediately after the false twist texturing. Device for false twist texturing of a thread (4) with a supply unit (17) which draws the thread (4) from a supply spool (1), with a heated drawing pin (18) in a drawing zone downstream of the supply unit (17), with a first supply unit (2), with a heating device (5), with a cooling device (6), with a false twister (7), with a second delivery unit (3) and with a winding device (10),
characterized in that
a thread guide (19) in the thread path is arranged downstream of the stretching pin (18), which is designed to be adjustable on the stretching pin (18) for setting a predetermined wrap angle of the thread (4). Device according to claim 14,
characterized in that
the thread guide (19) is adjustable in a guide (20) which forms a guide path with a substantially constant distance from the circumference of the stretching pin (18).

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