DE1435392B2 - Process for making a synthetic latent crimp yarn - Google Patents

Description

The invention relates to a method for producing a latent curl having, Synthetic, continuous yarn or the like, in which the yarn is passed through a heated drawing zone and then passed between two meshing gears.

In a known method of the type described above, threads are passed through a heating zone and passed between gears. The gears are known in this method warmed by constant contact with the heated threads coming from the heating zone, so that a fixation of the threads is not achieved (Swiss patent 315 283).

According to the invention it has been found that the resistance of the crimp suffers as a result.

The invention is therefore based on the object of developing a method, the application of which is a almost permanent crimping guaranteed.

The solution to this problem is that the yarn passed several times between the gears and is cooled at the same time.

Characterized in that the yarn in particular during the first pass through the gears, e.g. B. by an air supply device is fixed and so under controlled conditions the gears several times happens, a very effective and permanent crimp is achieved.

The invention is illustrated below with reference to a drawing.

F i g. Fig. 1 is a perspective schematic view of an apparatus for making the textured threads according to the invention;

F i g. Fig. 2 is an enlarged view of a cross section of the thread showing a symmetrical arrangement the flap has which by the in F i g. 1 into an arbitrary, non-symmetrical arrangement can be changed;

F i g. 3 is an enlarged view of a Y-shaped cross section of a thread showing a displacement of the long lobe through the device according to the invention;

F i g. 4 is an enlarged view of a Y-shaped cross section of a thread showing a shift shows one of the short lobes through the device according to the invention;

F i g. Figure 5 is an enlarged view of a multi-lobed, sinusoidally crimped suture;

F i g. Figure 6 is a sketch of the textured yarn according to the invention;

F i g. 7 is an enlarged view of Y-shaped ones Cross-sections of a bundle of threads showing the displacement of one of the lobes.

In the case of the schematically shown in FIG. 1 treatment device shown is the thermoplastic endless

ίο Yarn 10, for example made of polyamide or the like, which consists of a bundle of smooth, essentially parallel multi-lobed threads that are not completely oriented, is supplied from a yarn source. Since the yarn is not fully oriented, it is necessary to stretch it to obtain the optimal degree of molecular orientation. The yarn source can be, for example, a yarn package 11 which comes from a conventional spinning device.
The yarn 10 is drawn off from a bobbin 12 and passed over a stretching pin 13 in the usual manner. A grid-like stretching device can also be used in place of the one shown, or the stretching device can be omitted entirely. From the drawing pin 13, the yarn 10 is guided through a yarn guide 14 to a yarn delivery mechanism 15, which consists of a pair of rotatable feed rollers, at least one of which is positively driven. The rollers have parallel axes and engage with one another during operation in order to convey the yarn without slippage.

From the delivery mechanism 15, the yarn 10 is passed downwards and around a heated drawing pin 16, which heats the yarn and helps to give the yarn elongation. The pen is firm and related the axes of the feed rollers are axially inclined and have a smooth surface. After that Yarn 10 has been passed around pin 16 as many times as desired, it becomes rotatable downward between Gears 17 and 18 guided with parallel axes, which a multitude of uniform turns into Have teeth 19 extending in the longitudinal direction. An air line 20 is provided around the gears 17 and 18 at a temperature low enough to cool the yarn so that the Fixation of the yarn during the first passage of the yarn between the gears 17 and 18 is performed. The gears 17 and 18 are attached to shafts 21 and 22 or form one therewith Unit. To drive the gears in unison, outer spur gears 23 and 24 are provided, which are firmly attached to the shafts 21 and 22. After the yarn has wrapped part of the Circumference of one of the gears was guided, it is directed away tangentially and around part of the circumference a freely rotatable roller 25 which is mounted next to the gear 17 out. The yarn 10 is wound several times around the gear 17 and the roller 25 (FIG. 1), the peripheral speed of the gears 17 and 18 is much larger than that of the delivery mechanism 15. The axis of the roller 25 is mounted at an angle slightly inclined with respect to the axes of the gears 17 and 18, to ensure a longitudinal distribution on the periphery of the gear 17 and the roller 25 to to prevent overlapping of the twine turns. Then the yarn after the outermost turn is formed, passed vertically downwards, optionally through a yarn guide 26.

The yarn is wound by a known ring spinning device 27. This includes a sleeve 28, which is driven by a driven belt 30 on which the yarn winding 31 is formed will. The arrangement further includes an up and down spinning ring 32 which is a ring traveler 33, which is able to move freely around the bobbin 28 while the yarn is in a rotated to a certain extent and wound onto the bobbin.

It may be desirable to have at least one of the gears conical. This tends to When the yarn breaks, the yarn tends to move away from the gear instead of being piled and tangled on top of it to become.

When the gears 17 and 18 are conical and the yarn longitudinally along the gears advances, the extent to which the yarn is deformed into a wavy shape increases while it is carried out between the gears, with the frequency of the corrugations steadily decreasing. The yarn tension is reduced after each passage of the yarn through the gears.

In Fig. Figure 2 shows a Y-shaped thread with one leg longer than the other. This type of cross-section has been found to be particularly suitable for texturing with the apparatus specified above. The circle A with a radius R circumscribes the Y-shaped thread 34 which is shown in cross section. Within the cross-sectional arrangement there is a circle B with a radius R '. As can be seen, circle B is eccentric with respect to circle A. The straight line distance between the center of circle A and the center of circle B is given as ΔC . It is desirable that the degree of eccentricity be at least 10 and up to 60 "/" and more. The eccentricity is defined by the following expression:

AC R '

100

F i g. Figure 3 illustrates the bending of the long leg from its normal position assumed during the manufacture of the thread, the bending being the result of texturing using the apparatus set forth above. Line 35 extends from the tip of the long leg to the center of the circumferential circle (not shown). Line 36 extends from the tip of the long leg in its displaced configuration to the center of the circumferential circle. These lines enclose an angle α which is between 0 and approximately 45 ° C. The changes in the angle α of the threads which have been textured with the described device according to the invention are distributed arbitrarily among the threads and are arranged in circles along the length of a given thread. This has the effect of improving the appearance of the threads according to the invention.

F i g. Figure 4 illustrates the bending of one of the shorter legs against the other short leg and out of its normal position assumed during the manufacture of the thread, the bending resulting from texturing using the device according to the invention. Line 37 extends from the tip of the leg to the center of the circumferential circle (not shown). Line 38 extends from the tip of the leg in its displaced position to the center of the circle. These lines form an angle α as indicated above.
F i g. Figure 5 shows the sinusoidal or curved image of a single thread 40 as it is formed according to the method according to the invention. It has been found that bending the lobes advantageously changes the high gloss attached to multilobed filaments. As can be seen, the point of maximum bending of the flap 41 is approximately at the apex of the crimp and the point of minimum bending 41 is approximately in the middle between the one on top of the other.

following vertices. '*'

Contrary to expectations, not only are the sinusoidal ripples, but also the vertices the threads arranged at an arbitrary distance from one another. In known, achieved by means of gears Crimps, the gears are heated, leaving juxtaposed threads, and vertices straight portions extending therebetween at substantially identical locations along their lengths to have. As in Fig. 6, the location of the crimp apices is located The thread in relation to the other threads of the bundle is not in a certain pattern, but is random. This increases the bulkiness, which is very desirable.

F i g. 7 shows how the angle α can change in the case of adjacent threads at one point along the length of the threads. For example, the angle α for one of the lobes of the cross section 42 is almost zero. On the other hand, the long leg of the cross section 43 is bent to a considerable extent. Other degrees of curvature can be seen from this figure.

After being heated and drawn at the same time, and then cooled and puckered at the same time, the yarn is became, considerably capable of potential curling. Such a potential curl can when you get the stretched deformed thermoplastic Yarn a final heat treatment in a hot aqueous medium such as steam subjugated, or by warmth, or by combining both, in a relaxed or near relaxed state can be fully developed. This subsequent heat treatment is developed the potential crimp, an ability which is found in the yarn from a previous operation was induced and fixed at the same time the so developed crimp, whereby the yarn increased Bulkiness, curl, and extensibility are imparted. The threads according to the invention can be made of a wide variety of thermoplastic filament forming resins. The yarns can according to known procedures from these resins including melt extrusion, wet spinning processes and the dry spinning process. As examples of thread-forming synthetic Polymers which are included in the thread-forming thermoplastic resins are closed name: polyethylene, polypropylene, polyurethane, copolymers of vinyl acetate and vinyl chloride, the copolymers of vinylidene chloride and a small amount of monoolefinic compounds, which are copolymerized therewith, such as vinyl chloride, homopolymers of

Acrylonitrile, copolymers of acrylonitrile and a small amount of at least one monoolefinic Compound copolymerized therewith and polymeric mixtures containing acrylonitrile contained in a larger amount associated with copolymers of vinyl chloride and Acrylonitrile, linear polyesters of aromatic dicarboxylic acids and divalent compounds such as Polyethylene terephthalate and dipolyester, made from terephthalic acid and bis-l, 4- (oxymethyl) -cyclohexane are obtained, linear polycarbonamides, such as polyhexamethylene adipamide, polyhexamethylene sebacamide, polymeric monoamino monocarboxylic acids such as polymeric 6-aminocaproic acid, linear polycarbonates and other thread-forming thermoplastics Polymers. Mixtures of such filament-forming synthetic polymers can also be used will. The method according to the invention is particularly suitable for treating yarns, which are generally referred to as polyamides, and their thread-forming copolymers.

Both twisted and untwisted yarns can be used. A pre-twist of the yarn is generally not necessary and is generally avoided for economic reasons. Of the The denier of the thermoplastic yarns can vary considerably like the denier of the individual threads, whereby the ordinary titers of the technically available yarns are completely suitable. Yarns which are different Compositions and titers can be combined before processing in accordance with the invention will.

The temperature of the heated draw pin 16 depends on many factors including the type of Yarn, the linear yarn speed and the structure. The temperature of the yarn should preferably be are below the temperature at which adjacent threads come together during processing glue. However, the temperature should be high enough for the yarn to interlock the teeth of the gears can be deformed or warped without breaking the threads. the When processing polyamide, the temperature to which the yarn is subjected can be in the range of 140 to 240 ° C.

When using the device according to the invention and when carrying out the method according to According to the invention, a pontentially or latently crimpable yarn is produced which can easily be converted into a bulky highly crimped, stretchable, continuous filamentary yarn can be converted. »Bausch« refers refers to the relative volume occupied by a given weight of yarn. So had an increased bulk yarn such as that of the invention, greater coverage, and more Warmth. "Crimped" refers to the fact that the threads have many crimps, curls, loops Od. The like. Contained in a sinusoidal pattern along the lengths of the threads and in one or more planes. "Extensible" refers to the yarns according to the invention are resilient and capable of absorbing slight longitudinal tension and can therefore easily be stretched to a considerable length without permanent stretching can. For example, the yarn can be 10 to 100% or more of the undrawn or relaxed Length and immediately returns from this stretch to the starting position. For some uses it is preferred to consider the potential crimp ability of the yarn develop after it has been further processed. For example, it can be stretched and deformed Yarn, before it is subjected to a final heat treatment, advantageously knotted into a carpet and then the heat treatment is carried out

ίο be. The tufts of gamba on the surface of the carpet are puffed up to a considerable extent, thereby adding to the carpet give a better look. In such a way, the potential crimpability of the yarn, which located on the back of the carpet and in the base material, not developed as it is on these points is recorded, which ensures a more economical use of the game will. It should be noted that the knotting operation can be carried out more conveniently when the crimping is then developed.

The invention is illustrated in more detail below using an example.

example

The filaments used as the yarn source were melt-spun polyhexamethylene adipamide and the cross section of the threads was Y-shaped. The gam consisted of 68 of these undrawn threads, each of which has a titer of 60 and a twist of 0 turns each had 2.5 cm. The degree of eccentricity of the circles which inscribe and circumscribe a cross section of the threads can was 17%.

For the treatment of the yarn, a device was used which corresponds to the one shown in FIG. 1 corresponded to used. The yarn was unwound from a bobbin for treatment by passing it through a pair directed by positively driven feed rollers, the take-off speed about 90 m each Minute was. The thread was fed once around a draw pin by the feed rollers Gam described a spiral path around it. The surface temperature of the pen was measured using a regulated electrical resistance heater, which was attached inside the extension pin, held at 210 ° C. The thread was passed between two wheels fitted with metal teeth, which were in mesh with one another, but the teeth did not touch. The wheels were driven uniformly at a predetermined speed so that in the yarn between the feed rollers and the take-off from these wheels achieved an elongation of about 350% became. The yarn was passed through the wheels an additional three times before each pass the yarn is directed around a spaced roller. After that, the yarn was made in the usual way collected on a ring twist arrangement.

A knotted carpet was produced from the yarn treated in this way. The carpet turned to steam exposed at 130 ° C, thereby developing the potential curl. The finished carpet had puffy appearance and made a pleasant

take an impression. The angle α, as measured above in the cross-sections of the game, changed randomly along the length of the threads.

1 sheet of drawings

Claims (2)

Patent claims: 1. A method of making a synthetic, latent crimp, continuous Yarn or the like, in which the yarn is passed through a heated stretching zone and then is passed between two meshing gears, characterized in that that the yarn is passed several times between the gears and is cooled at the same time. 2. The method according to claim 1, characterized in that yarn threads with multiple lobes Cross-section passed between the gears and cooled at the same time.