US3058291A - Permanently crimped synthetic textile products and method for producing the same - Google Patents

Description

1952 G. HEBERLEIN ETAL 3,058,291

PERMANENTLY CRIMPED SYNTHETIC TEXTILE PRODUCTS AND METHOD FOR PRODUCING THE SAME Filed Feb. 11, 1957 2 Sheets-Sheet I INVENTORS GEOAG HEB ERLEl/V- PHILIPPE LA N6.

MMMOMs/MM ATTORNEY .5.

Oct-16, 1962 G. HEBERLEIN ETAL 3,058,291

PERMANENTLY CRIMPED SYNTHETIC TEXTILE PRODUCTS AND METHOD FOR PRODUCING THE SAME 2 Sheets-Sheet 2 Filed Feb. 11, 1957 INVENTORS. GEORGE HEEL-PL E/M PH/L IPPEL/I N6. BY

ATTOR/VEY5.

United States Patent 3,058,291 PERMANENTLY CRlMlED SYNTIETIC TEXTILE PRODUCTS AND METHOD FOR PRQDUCING THE SAME Georg Heberiein and Philippe Lang, Wattwil, Switzerland, assignors to Heherlein Fatent Corporation, New York, N 1%., a corporation of New York Filed Feb. 11, 1957, Ser. No. 63?,247 Claims priority, application Austria Feb. 15, 1956 7 Claims. (Cl. 57l40) This invention relates to permanently crimped synthetic organic polymer yarns, to woven or knitted articles made therefrom and also to processes for producing the same.

It is well known that a permanent crimp may be applied to synthetic organic fiber yarns such as polyamides, polyesters and the like. These crimped yarns of the so-called stretch type are produced by high twisting, heating, setting and detwisting. The finished yarn can be produced by false-twisting, wherein the yarn is first twisted in one direction and subsequently untwisted or detwisted to the same extent. In the initial highly twisted state, the yarn is subjected to elevated temperature although substantially below the lower limit of the melting point range of the yarn, i.e., generally more than 30 C. below. At this temperature the yarn yields as highly twisted, and subsequent cooling permanently sets the heat and twistinduced deformation. The above operations are carried out continuously, and twisting and detwisting are effected by the yarns passage over a false-twister head, which is generally provided with a metal loop of special design, or roller around which the yarn passes, rotating at very high speed. A single yarn which has been processed by initial twisting in the clockwise or 8 direction, even though detwisted, exhibits a torque in the direction of initial twisting. Accordingly, such a yarn is subsequently plied with another processed yarn initially high twisted counterclockwise, or Z, to produce a two-ply thread of substantially no torque. Knitted or woven articles made from the resulting two-ply thread exhibit excellent stretch characteristics, but are entirely too soft for certain applications.

In one aspect, the present invention provides a process for producing a permanently crimped yarn of synthetic organic textile material, which When knitted or woven produces a fabric which displays a crisp, much harder hand, i.e., it is considerably rougher to the touch than material produced by the above prior art method.

By way of definition, false-twist device or falsetwisting device as employed herein is intended to include the following, namely, a heating zone, a false-twister head and an intermediate cooling zone. These are the three elements, together with means for moving the yarn, required of any device for practice of the present process. The aforementioned means may, as is well known in the art, be only a take-up device, a feed and take-up, or as we prefer, a feed, an output and a take-up device. The term false-twisting apparatus as used herein is intended to include the false-twist device, and all elements essential to the proper functioning thereof.

In the drawings:

FIG. 1 is a diagrammatic side elevation of an apparatus for carrying out the process of the present invention;

FIG. 2 is a detailed sectional elevation of the positive cooling device of the invention;

FIG. 3 is a photographic enlargement of a permanently crimped 70 denier, two-ply nylon multifilament yarn, each of the single ends having been produced by the method of the present invention, one yarn initially highly twisted S and the other 2;

FIG. 4 is a photographic enlargement of a knitted article made from the yarn of FIG. 3;

FIG. 5 is a photographic enlargement, similar to FIG 3 and to the same degree of magnification, of a permanently crimped 70 denier, two-ply nylon multifilament yarn produced by a conventional false-twist process; and

FIG. 6 is a photographic enlargement of a knitted article made from the yarn of FIG. 5, and knit in the same manner as the article of FIG. 4.

The invention accordingly consists of the novel products as well as the novel processes and steps of processes according to which such products are manufactured, the specific embodiments of which are described hereinafter by way of example and in accordance with which we now prefer to practice the invention.

Generally speaking, the present process is carried out with conventional false-twisting apparatus which, in accordance with the invention, has been provided with a rapid cooling zone, described in detail hereinafter, intermediate the heating zone and the false-twister head wherein the traveling yarn is subjected to the action of a positively directed cooling fluid, and thus quickly cooled. In prior art processes and apparatus, the highly twisted heated yarn is cooled merely by passage through air, i.e. through a zone open to the atmosphere between the heating device and the false-twister head.

According to the process of the present invention, the synthetic multifilament yarn in the high twisted state is subjected to a heat treatment at temperatures considerably higher than heretofore employed in the permanent crimping of said yarn. Specifically, the yarn is exposed in a heating zone to a temperature from the lower limit of the melting point range of the synthetic yarn to about 20 C. below the lower limit of said melting point range, for a period ranging from about 0.4 to 2 seconds. These contact times are less than the normal period of contact hereto-fore widely employed when treating yarns of equivalent denier. In the aforementioned prior art methods, the yarn was heated to temperatures only sufficient to enable the material to be deformed without any substantial surface softening of the individual synthetic fibers, such temperatures not exceeding about 30 C. below the lower limit of the yarn melting point range. However, at the higher temperatures employed in the present process, considerable softening of the outer surface of the fibers is produced with resulting adherence of the individual fibers, which results in a yarn of markedly different characteristics.

The hot, highly twisted yarn issuing from the heating zone is then immediately and quickly cooled through heat exchange with a cool inert fluid, for example, a positively directed stream of cool air under pressure. Satisfactory and eflicient cooling of the traveling yarn is effected through direct heat exchange by passing the same through a tubular member and positively directing a stream of cool air therein countercurrently of the direction of yarn travel. It is difiicult to specify the exact cooling air temperature necessary to effect the required rapid cooling, since it will be governed by the yarn material and denier, heating zone temperature, air pressure, yarn speed, etc. It is sufficient to say that the temperature of the cooling fluid is below ambient air temperature. At just under room temperature, for example, the rate of air flow will have to be greater than when air at say 5 C. is employed. This positive cooling action, as distinguished from mere convection cooling in a zone open to the atmosphere as was the practice heretofore, rapidly hardens the soft outer surface of the deformed fibers, and contributes to the crisp hand of goods produced from the thus processed yarn. Furthermore, rapid cooling is required for complete setting before the yarn reaches the twister head.

Heretofore, the high temperatures employed herein were avoided since it was thought that the fibers would be substantially weakened and even broken, or virtually completely fused or stuck together during heating, with the result that the finished yarn would be commercially unusable. However, we have found that this is not the case when the yarn is subjected to the higher temperature for shorter periods, rapidly cooled, and the entire operation carried out with the yarn under proper tension.

Thus, in addition to the higher temperature, shorter exposure time and more rapid positive cooling, in accordance with the present invention, it is necessary that the traveling yarn be under proper tension. Correct yarn tension may be achieved, by controlling the rate of feed and rate of delivery from the false-twisting device, where means are provided for positively feeding and delivering the yarn, taking into account the particular snythetic fiber, its denier and the heating temperature, etc. Tension will of course be controlled in apparatus having only positive delivery and/or take-up means with the aid of tensioning means at the input end of the false-twisting device. The yarn may be fed to the false-twisting device at a rate greater than it is delivered therefrom. In other words, the yarn is overfed. In the present process the rate of over-feed may be as high as 15%. In some cases, however, an o-verfeed is unnecessary. For example, nylon 70 denier yarn when treated at temperatures intermediate the above specified limits may be underfed as much as 8%. As indicated, tension is determined by the particular synthetic material, yarn denier, temperature, required exposure time, etc. and it is difficult to specify a precise degree of over or underfeed to cover all circumstances. However, it is sufficient to say that an overfeed will often be employed to produce acceptable crimped yarn, and that the rate of overfeed will not exceed about 15%. Further, it may be said that the yarn tensions employed in the method of the prior art must be adjusted to take into account the higher temperatures and more rapid cooling employed herein.

The present process is applicable to the production of cri-mped yarn of polyamide fibers and particularly the poly condensation products of hexarnethylenediamine and adipic acid (nylon), as well as polycondensation products of ll-aminoundecanoic acid or of epsilon-caprolactam. Other synthetic organic textile fibers may also be employed, including the fibers on a polyvinyl basis and polyester fibers. With nylon (MP. between about 248 and 255 C.) yarns excellent results are obtained at temperatures between about 228 and 240 C. for the above specified times. Acceptable results are even obtained with nylon at a temperature of 245 0, being below the melting point range, with overfeed and an exposure time of 0.5 second. lactam the temperature is desirably between about 185 and 195 C., and with a polyester yarn such as polyethyleneglycol terephthalate (Ml between about 250 and 256 C.), temperatures between about 235 and'250" C. produce excellent results.

Referring now to the improved apparatus for carrying out the process of the present invention, attention is directed to FIG. 1 which illustrates a false-twisting apparatus having feeding, delivery and take-up means. in the apparatus shown, the elements are arranged on a frame 1. However, it is to be understood that the elements might also be disposed vertically instead of generally horizontally. From a yarn supply package 2, the yarn Y is passed over guides 3' and 3 to an input or feeding device 4, which consists of a contacting roller pair 4, the lower one of which is driven by means not shown. The yarn is passed between the rollers and thence through the heating device 5, which is preferably an elongated member having ends open to the atmosphere. The heating device 5 is desirably a metal tube disposed axially of the direction of travel of the yarn Y, which tube is wound with resistance wire. Alternatively, the heating device may be a heated surface, preferably a metal surface With a polyamide yarn of epsilon-caprobrought to the necessary temperature by electric or other means, and the highly twisted yarn passed thereover in direct contact with this surface. In any event, it is important that the heating device be provided with means for very close and even control of temperature over its entire length. As thus far described, the apparatus is similar to that in current use.

From heating device 5, the yarn is passed through a cooling device 6, described in detail below, and thence through a false-twister head 12, which is caused to rotate at very high speeds, as by a motor 7. The false-twister head acts to twist the moving yarn back to feeder 4, and also serves to detwist the yarn as it passes over the falsetwister head. In the apparatus illustrated, the yarn then passes through a delivery or output device 8, consisting of a pair of rollers, the lower of which is driven, similar to the roller pair of feeding device 4. Subsequently, the yarn is passed to a take-up device, which includes a tension regulating element 9, a yarn guide It) which reciprocates, and a take-up tube or package 11.

As indicated above, the essential elements of the falsetwisting apparatus are the heater 5, cooling device 6 and false-twister head 12, plus means for advancing the yarn, which elements are referred to as the falsetwisting device. Three such yarn advancing means are illustrated as 4, 8 and the take-up elements 911. Aside from the cooling device 6, the entire apparatus is conventional. In apparatus of this type heretofore, cooling was effected merely by passing the yarn through a space between the 1 heater and the false-twister head which was open to the atmosphere. Such normal air convection cooling was found inadequate for the present process, and prompted development of means and apparatus for rapidly cooling the hotter yarn.

A preferred form of the cooling device generally indi cated as 6 in FIG. 1 is illustrated in detail in FIG. 2. It consists of a tube 13 positioned axially of the direction of travel of the yarn Y, preferably of glass. The end of tube 13 adjacent the false-twister head is fitted with a glass capillary tube 14 with an opening 16 at its outer end just sufficient for the passage and threading of the yarn. Alternatively, tube 13 may be drawn at its aforementioned end to provide a constricted opening. Access to the interior of capillary tube 14 is provided rearwardly of its smaller end, as at branch 15. A cool fluid which is inert with respect to the yarn, air for example, is'introduced under pressure to tube 13 through this branch. Because of the small diameter of opening 16, the cooling fluid flows through tube 13 in the direction of the heating device 15, This counter-current flow, illustrated by the arrows in FIG. 2, provides quick and efiicient cooling which results in the necessary rapid setting of the hot, highly twisted yarn.

The tube device illustrated in FIG. 2 has been found to be especially well adapted to the cooling problem encountered, and cool air is the preferred coolant. Whenever cooling is effected through direct heat exchange with a stream of cooling fluid, the stream is desirably caused to flow axially of the yarn, which avoids undue vibration of the traveling yarn. Alternatively, a pair of opposed streams of cooling fluid could be directed at the traveling yarn. Also, cooling might be effected by means of a jacketed tube with a refrigerant in the jacket.

Referring again to the proper tension in the yarn traveling through the false-twisting device, in the false-twisting apparatus of FIG. 1, tension is regulated by the speed of the roller pairs of feeding device 4 and delivery device 8. In order to achieve an overfeed, the rollers of feeding device 4 are driven at a linear rate greater than the linear speed of the rollers of delivery device 8. At overfeeds up to 15%, entirely satisfactory yarn is produced, one with a much harder surface than is produced at lower temperature, with slower cooling and at higher yarn tensions.

It is to be understood that the process of the present invention is not restricted toany particular feeding or de a livery device, and the false-twisting apparatus of FIG. 1 is an example only of one type of apparatus for producing permanently crimped synthetic yarns.

Attention is now directed to FIGS. 36 and particularly the photograph of FIG. 3 illustrating a magnified 70 denier two-ply crimped nylon multifilament yarn. Each of the single ends was individually highly twisted to 2800 turns per meter and subjected to a temperature of 238.5 C. for a period of 1.3 seconds, after which it was quickly cooled by passage through the cooling apparatus illustrated in FIG. 2 fed with pressurized air at a temperature of about 15 C. The yarn was subsequently detwisted. A yarn highly twisted in the S direction was plied with one highly twisted in the Z direction to produce the 70 denier two-ply yarn of FIG. 3.

The yarn of FIG. 5 is also a 70 denier two-ply nylon multifilament, but crimped by a conventional false-twist method. One of the single ends was highly twisted 2800* turns per meter S and the other 2800 turns per meter Z. Except for the direction of twist, each yarn was subjected to the same conditions during permanent crimping; namely, each ply was heated to 210 C. for a period of 1.3 seconds and subsequently cooled by passage through an open zone intermediate the end of the heater and the false-twister head. The temperature of the surrounding air was 20 C. and the length of the open zone was 0.5 foot.

-A casual examination of FIGS. 3 and 5, which show the yarns magnified to the same degree, reveals an obviously diiferent appearance of the yarn produced by the method of the present invention from the voluminous yarn produced by the aforementioned ordinary prior art method. It is not possible to distinguish the yarn plies in FIG. 5, and the individual filaments of the yarn are easily seen. It is noted that each of the filaments have been deformed by the crimping operation. The yarn is very light and fluffy and exceedingly soft to the touch as would be supposed. The diameter of the FIG. 5 yarn is substantially greater than that of the average mean diameter of the plied yarn of FIG. 3.

Turning to FIG. 3 the two plies of the yarn of the present invention are easily detected, and they may be readily separated. The single ends themselves appear as collections of filaments partially adhering to one another at random intervals. Adherence of the individual fibers is the result of the more severe heat treatment which caused the surfaces of the fibers to become quite soft. However, the degree of adherence is not such that the single ends appear as monofilaments. That is to say, the yarn has a definite flufliness, but the degree of flufiiness is less than that of the ordinary crimped yarn of the prior art. The yarn of the present invention is not voluminous as this term was employed to describe the yarn of FIG. 5, and it is substantially harder to the touch. For example, one may pull the yarn of FIG. 5 over his finger without feeling its passage, whereas a similar contact with the yarn of the present invention feels as does a hard cotton thread.

FIGS. 4 and 6 are enlargements of knitted articles, under very slight tension, made in exactly the same way from the yarns of FIGS. 3 and 5, respectively. The wales of the fabric of FIG. 6 are straight, substantially parallel, evenly spaced and clearly defined. To the touch the fabric is firm and smooth. On the other hand, the fabric of FIG. 4 is hard or very crisp and rough. The wales of the FIG. 4 fabric are not evenly spaced or clearly defined, nor are they parallel. The surface of the fabric is uneven and irregular, with random perforations therein. It bears little resemblance to the knitted fabric produced from ordinary crimped yarn.

The invention is further illustrated by means of the following examples:

Example 1 Yarn of polyhexarnethylene adipamide, 70 denier, 23 filaments, with a twist of 30 t./m. Z was temporarily high twisted to 2800 t./m. S by means of a false-twist device. The yarn in the high twisted state passed through a heating device at a rate such that it was exposed for 1.35 seconds to hot air at a temperature of 243 C. It was immediately cooled in a Zone fed with air at 10 C. The so treated yarn was plied to t./m. S with a similarly treated single end yarn which had been temporarily high twisted to 2800 t./m. Z. The two-ply yarn exhibited appreciable crimp. Articles knit therefrom exhibited a compact, crisp hand.

Example 2 A yarn of polyhexamethylene adipamide, 100 denier, 34 filaments, with a twist of 30 t./m. 2 was temporarily high twisted by means of a false-twist device to 2470 t./m. S. The yarn was passed in the high twisted state through a heating device in which it was exposed for 0.5 second to the efiect of hot air at a temperature of 245 C. It was then quickly cooled. The delivery speed of the yarn from the false-twist device was about 5% less than the speed at which it was fed to the device. The so treated single yarn was plied as described in Example 1 with a single yarn that had been temporarily high twisted to 2470 t./m. Z. The yarn displayed an intensive crimp and a crisp, dry hand in the knitted state.

Example 3 A polyamide yarn of epsilon-caprolactam, 30 denier, 6 filaments with a twist of 20 t./m. 2 was temporarily high twisted to 4300 t./m. S by means of a false-twist device and in the high twisted state passed through a heating device in which it was exposed for 2 seconds to the effect of hot air at C., and subsequently quickly cooled. The delivery speed of the yarn from the falsetwist device was retarded by about 5% as compared to the rate of feed to the device. From two so obtained single yarns, one high twisted Z, a two-ply yarn was produced, as described in Example 1. It displayed a typical crimp, and a rough hand in the knitted state.

Example 4 A polyamide yarn of epsilon-caprolactam, 70 denier, 2:0 filaments, with a twist of 15 t./m. Z was temporarily high twisted to 2820 t./m. S by means of a false-twisting device and passed in the high twisted state through a heating device in which it was exposed for 0.57 second to the effect of hot air at 2185 C. It was subsequently rapidly cooled as in Example 1. The delivery speed of the yarn was retarded by about 2.3% as compared to the feeding speed to the false-twist device. The yarn was plied with a similarly treated Z-twisted end, and displayed a permanent crimp and a crisp dry hand in the knitted state.

Example 5 A polyester yarn of polyethyleneglycol terephthalate, 40 denier, 34 filaments with a twist of 33 t./m. 2 was temporarily high twisted to 3680 t./m. S by means of a false-twist device and passed in the high twisted state through a heating device in which it was exposed for 1.6 seconds to the effect of hot air at 235 C. It was immediately cooled by contact with flowing cool air. The yarn in the false-twist device was overfed 10%. The yarn processed into a two-ply yarn with an end high twisted Z displayed a pronounced crimp and a fairly dry, hard hand in the knitted state.

Example 6 A polyester yarn of polyethyleneglycol terephthalate, 70 denier, 34 filaments with a twist of 6 t./m. 2 was temporarily high twisted to 3000 t./m. S by means of a false-twist device. The yarn passed in the high twisted state through a heating device in which it was exposed for 1.5 seconds to the eifect of hot air at 227 C., and subsequently was rapidly cooled. Yarn overfeed was 7.5%. The yarn processed into a two-ply yarn, as aforesaid, disin the knitted state. a Exam pie 7 A polyester yarn of polyethyleneglycol terephthalate,

150 denier, 72 filaments with a twist of 200 t./m. S was temporarily high twisted to 1950 t./rn. Z by means of a false-twist device and passed through a heating device in the high twisted state wherein it was exposed for 0.45 second to the effect of hot air at 251 C., and subsequently rapidly cooled. Overfeed was 7%. An equivalent polyester yarn that had an initial twist of 80 t./m. S was temporarily high twisted to 1950 t./rn. Z and treated under the same conditions. Both single yarns were processed into a ply of 140 t./m. S, which displayed a permanent crimp and a fairly dry, hard hand in the knitted state.

Example 8 A polyamide yarn of polyhexamethylene adipamide 70 denier, 23 filaments, with a twist of 30 t./m. 2 was temporarily high twisted by means of a false-twisting device to about 2800' t./m. S. The yarn passed in the high twisted state through a heating device in which it was exposed to hot air at 238.5 C. for 1.3 seconds, and subsequently quickly cooled. The yarn passing through the false-twist device was underfed about 8%, i.e. the feed rollers 4 had a circumferential speed of 46.1 meters per minute and the delivery rollers 8 had a circumferential speed of 52 meters per minute. After leaving the falsetwisting device the yarn was wound under low tension on a take-up bobbin. Two of such similarly treated single yarns, one of which had been temporarily high twisted to 2800 t./m. S and the other to 2800 t./m. Z, are plied together to 100 t./m. 8. this yarn showed a relatively firm, or hard hand.

What we claim is:

1. A process for producing permanently crimped synthetic organic textile yarn selected from the group consisting of polyamides and polyesters by means of a falsetwisting device which comprises traveling said yarn through a heating zone, subjecting said yarn in said zone to a temperature from the lower limit of the melting point range of the synthetic yarn to about 20 C. below the lower limit of said melting point range for a period of 0.4 to 2 seconds, thereby causing incipient surface melting and bonding at random intervals along the yarn due to the false-twisting in the heating zone, then hardening the bond at said random intervals by rapidly lowering the temperature of the yarn by the aid of a coolant as the yarn passes from the heating zone, and passing the yarn so treated through a false-twister head and subsequently to a take-up package, whereby a substantially harder, less voluminous yarn than ordinary stretch yarn is formed.

2. A process in accordance with claim 1, in which the rate at which said yarn is delivered from the false-twisting device is up to about 15% less than the rate at which it enters said device.

3. A process for producing permanently crimped nyon yarn by means of a false-twisting device, which comprises passing said yarn through a heating zone, subjecting the yarn in said zone to a temperature between about 228 Knitted products made from' and 245 C. for from 0.4 to Zseconds, thereby causing incipient surface melting and bonding at random intervals along the yarn due to the false-twisting in the heating zone, then passing said yarn into. a confined zone, subjecting the yarn therein to contact with a flowing cooling fluid inert with respect to said yarn, thereby hardening said bond at random intervals in the yarn, and passing the thus cooled yarn through a false-twister head, and subsequently to a take-up package.

4. A permanently crimped synthetic organic multifilament yarn selected from the group consisting of polyamides and polyesters, the filaments of which adhere to one another at random intervals, said yarn being substantially less voluminous and less fluffy and substantially harder to the touch than ordinary stretch yarn of the same material and denier.

5. A two-ply permanently crimped nylon multifilament yarn, the filaments of which adhere to one another at random intervals, said yarn being substantially less voluminous and less fiufiy and substantially harder to the touch than ordinary stretch yarn of the same material and denier.

6. A stretchable fabric fashioned from a permanently crimped synthetic organic multi-filament yarn selected from the group consisting of polyamides and polyesters, the filaments of which adhere to 'one another at random intervals, said yarn being substantially less voluminous and fluify and substantially harder to the touch than ordinary stretch yarn of the same material and denier, the wales of said fabric being wavy and unevenly spaced, said fabric having a rough, uneven surface with random perforations therein and a'hard, crisp hand.

7. A stretchable nylon fabric fashioned from a permanently crimped nylon multifilament yarn, the filaments of which adhere to one another at random intervals, said yarn being substantially harder to the touch than ordinary stretch yarn of the same material and denier, the wales of said fabric being wavy and unevenly spaced, said fabric having a rough, uneven surface with random perforations therein and a hard, crisp hand.

References Qited in the file of this patent UNITED STATES PATENTS 1,909,192 Taylor May 16, 1933 2,044,135 Taylor June 16, 1936 2,079,133 Taylor May 4, 1937 2,089,199 Finlayson et al Aug. .10, 1937 2,322,094 Newhard June 15, 1943 2,369,395 Heymann Feb. 13, 1945 2,564,245 Billion Aug. 14, 1951 2,623,266 Hemmi Dec. 30, 1952 2,790,298 Kunzle Apr. 30, 1957 2,803,105 Stoddard et al Aug. 20, 1957 2,803,109 Stoddard et al Aug. 20, 1957 2,863,280 Ubbelohde Dec. 9, 1958 OTHER REFERENCES American Handbook of Synthetic Textiles, by Mauersberger, 1st edition, 1952. Textile Book Publisher, Inc. (page 979 relied on). e

Claims (1)

1. 4. A PERMANENTLY CRIMPED SYNTHETIC ORGANIC MULTIFILAMENT YARN SELECTED FROM THE GROUP CONSISTING OF POLYAMIDES AND POLYESTERS, THE FILAMENTS OF WHICH ADHERE TO

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