BE571137A - - Google Patents

Description

       

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   The present invention relates to the treatment of yarns or yarns to obtain a yarn of greatly increased volume and particularly relates to the formation of a bulky yarn composed of several fibers having individual convolutions and characterized by the presence of a large number of ring loops and protruding fiber ends irregularly distributed across the yarn surface.



   In U.S. Patent Application No. 261,635 of December 14, 1951, the formation of a new bulky yarn formed from filaments having most of the desirable properties of ordinary staple fiber yarns but differing in that it is composed of substantially continuous filaments In this yarn the bulk and appearance resembling that of a yarn formed from staple fibers are obtained by a large number of annular loops and other convolutions distributed randomly along the filaments and irregularly over the different filaments.

   Although this continuous filament structure has a distinct advantage for most applications there are textile uses which require a woolly, bulky or cashmere-like effect provided by a yarn having a large number of protruding filament ends.



  A yarn exhibiting the combination of properties formed by loose ends and filament convolutions increasing yarn volume would be desirable for these applications.



   With the exception of silk, natural, animal, vegetable and mineral fibers exist only in relatively short segments. The yarn prepared from these natural fibers necessarily consists of short fibers. In addition, large quantities of artificial continuous filaments are cut into fibers before being made into yarns. Treatment of such staple fiber yarns to introduce convolutions therein giving bulk to the yarn would be desirable whether or not free ends are required.

   When the desired effect requires protruding ends, it is very desirable to find a method for treating the continuous filament yarn to give it both bulk and a large number of protruding ends in one operation, thereby avoiding operations. the costs of cutting the continuous filaments into chopped fibers and of spinning these fibers into a yarn.



   An object of the invention is to provide a yarn having a large number of projecting free ends and having an improved volume provided by convolutions of the filaments of the type characterized by the presence of annular loops. Another object is to provide a yarn of spun fibers of improved volume, characterized by the presence of a large number of annular loops and of projecting fiber ends irregularly distributed along the surface of the yarn. Another object is to provide a process for the preparation of yarns having an improved volume from conventional yarns formed from cut and spun fibers.



  Another object is to provide a method of treating a continuous filament yarn to give it a greatly increased volume and a layer of protruding fiber tips in one operation. Other objects of the invention will emerge from the following description.



   In the drawings, which illustrate preferred embodiments of the invention,
Figo 1 is a side elevational view of an apparatus for carrying out the method of the invention;
Figo 2 is a side elevational view, partly in section, of another form of nozzle;
Figo 3 is an end view of the nozzle shown in Fig 2;
Figo 4 is a side elevational view, partly in section, of another form of nozzle;
Fig. 5 is a side view showing the appearance of an untreated wire

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 twisted prepared from a thread of continuous filaments (enlarged approximately 10 times);
Fig. 6 is also an enlarged view of an untwisted treated yarn prepared from two strands of continuous filament yarn;

   
Fig. 7 is also an enlarged view of a yarn processed from a strand of continuous filament yarn and a strand of cotton yarn;
Figo 8 is also an enlarged view of a yarn processed from a single strand of staple fiber yarn;
Figo 9 is a view also enlarged of a treated yarn prepared from two strands of staple fiber yarn;
Figo 10 is a schematic view of the arrangement of the yarn feed of the texture nozzle, the torsion nozzle, the winding cylinder and the winding system;
Fig. 11 is a schematic view of another arrangement similar to FIG. 10 but comprising a drawing cylinder with a stepped cylinder and a drawing finger;
Fig. 12 is another variant of FIG. 10;
Fig. 13 is a schematic sectional view of a textured nozzle flocking box;

   
Fig 14 is a schematic view of a set of yarn feed rollers, flock box, nip rolls and winding device;
Fig. 15 shows schematically on isolated strands how the cut fibers are taken in the loops introduced by a nozzle;
Figo 16 shows the staple fibers secured in the loops of Fig.



  15 which have been clamped to block the cut fibers;
Figa 17 shows the chopped fibers flattened against the load bearing fiber in an isolated strand;
Figo 18 shows how certain strands are wound around the bundle of filaments by the torsion nozzle, and
Fig 19 shows a modification in which a T-shaped tube is used in place of the texture nozzle. The T-tube can be any smooth material like glass, stainless steel etc., and its diameter can vary from 1/8 to 1/2 inch (3mm to 13mm).



   According to the invention, a new yarn is obtained which has a woolly or cashmere appearance due to a layer of projecting fiber ends and a particular volume compared to that of yarns formed from already known staple fibers, originating from fibers which exhibit convolutions in corkscrew, in loops and swirls, at randomly distributed intervals along their length and at variable distances on different fibers so as to obtain a lateral spacing between fibers o The most obvious characteristics of the yarn are the combination of a volume particularly with the woolly outer part formed by the protruding fiber ends, but the yarn is also characterized by the presence of a large number of annular loops and other convolutions in the fibers.

   The convolutions visible on the surface help to impart desirable properties to the yarn, but the less visible fiber convolutions within the yarn are even more important in that they give volume therein and warm the fabrics formed from it. of these threads.



   The characteristic loops of the fibers of the yarn have been called annular because they form small complete loops formed by a fiber coming back on itself, intersecting and then practically resuming the original meaning In mathematics a curve of this type describes a crunode .

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  Consequently, the characteristic loops will be more particularly defined by the term “crunodal loops”, and in the remainder of the description and of the claims they are loops of this type unless otherwise indicated. The majority of the loops visible at the surface of the wire are roughly circular in shape and are appropriately described as annular o The crunodal loops within the wire do not lend themselves to detailed examination but it is evident that the pressure of the surrounding filaments tends to set to these loops more complex shapes.



   Fiber ends and convolutions can be held in place by a twist given to the yarn. A single strand yarn may have Z or So twist In a multi-strand yarn, the individual strands are usually twisted in one direction and all of the strands and twisted together in the opposite direction, for example strands may present a Z twist and the yarn a Sa twist Unless the convolutions have been fixed, for example by heating the yarn forming the convolutions, the fibers return to their initial state when the yarn is untwisted and unraveled. Consequently, initial fibers straight lines take on an essentially rectilinear shape Of course if the fibers of the yarn were initially crimped or wavy,

   they resume this state when they are separated from the wire
The yarn of the invention is prepared by a process in which the yarn is passed through a fluid nozzle at high speed under conditions conducive to achieving the dual purpose of giving the yarn convolutions at a high volume and creating a high volume therein. large number of filament ends protruding, then twist the filaments together to hold the convolutions and the filament ends in place. In some respects this process resembles that of US Patent Application No. 26106350 However, additional critical conditions must be observed to obtain the desired layer of filament ends on the surface of the yarn.



   The starting yarn can be essentially continuous filaments or staple fibers, which can be natural fibers or chopped artificial filaments, or the yarn can include two or more of these types.



   When treating a yarn composed of substantially continuous filaments according to the invention, the yarn is passed through a nozzle operating under conditions such that the filaments are shredded at randomly distributed intervals to provide the desired free ends. In order to achieve this goal, the nozzle must first open the wire. The filaments of a yarn formed of un-twisted continuous filaments are easily separated by the turbulence created by a high-speed nozzle. The twisted yarn must be untwisted before the filaments can be separated, but this action can also be performed by the nozzle.

   Under suitable conditions the nozzle applies sufficient false untwist to the filaments of the yarn to allow the nozzle to open the yarn and this is true not only when the yarn is composed of a single twisted strand, but also when the yarn is twisted. is made up of several individually twisted strands. Once the filaments of the yarn have been separated, an appropriate turbulence of the nozzle animates them with a movement fast enough so that the bending resistance of the material which constitutes them is quickly exceeded and a more or less large part of the filaments is broke
The operation of the nozzle at or near the speed of sound, or near that speed of sound, achieves these goals of opening the yarn and throwing the filaments to a sufficient extent to shred them into relatively short ends.

   The distance traveled by the yarn in the nozzle should be less than the average length of the fibers produced by the breaking of the continuous filaments, so that the fibers are not detached from the yarn to an undesirable extent. After the wire comes out of the nozzle, it is twisted to hold the

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 fibers and convolutions obtained in place. The degree of the bursting effect varies with the flexural strength of the material constituting the filaments, all other conditions being similar, but the structure resulting from the treatment can be determined by the speed at which the yarn is passed. in the nozzle.



   The preparation of the yarn of the invention from a yarn formed of chopped fibers is simpler in at least one respect since it is not necessary to burst the yarn, but unexpected difficulties must be overcome otherwise the yarn. is torn off or almost unresponsive to treatment.



  The fibers of the copied fiber yarn must be held in place by twisting the yarn, but the yarn must be untwisted while in the nozzle for the treatment to have an appreciable effect. At speeds approaching the speed of sound, the nozzle applies a high untwisting torque as well as high thread tension. If the yarn is allowed to untwist under the influence of this torque for a distance in excess of the length of the fibers, the draw resistance of the yarn is reduced to such an extent that the tension created by the nozzle is sufficient to tear the yarn . When the yarn passes from the nozzle to a winder, it has been found that the untwisting action of the nozzle is limited to the length of the yarn between the feed and the winder.

   In other words, the torque of the nozzle applies a twist to the wire. The magnitude of this false untwist action is inversely proportional to the twist applied to the wire between the feed and the winding, because the tension imposes a torque which opposes the torque of the nozzle. Therefore, the false untwist can be controlled by increasing the tension, but this does not solve the difficulty because the total sum of the tension due to the nozzle and the winding tension then exceeds the tenacity of the yarn.



   According to the invention it has been found that a yarn wholly or partially formed of staple fibers held in place by twisting can be effectively treated by passing the yarn through a high speed fluid nozzle operating in such a manner. to apply a false untwist to the wire, the wire going to the nozzle being deflected on a point of contact to prevent the untwist upstream, then on another at the exit of the die so that the untwist does not propagate downstream , the distance between the two friction points being less than the length of the cut fibers, and preferably chosen so as to limit false untwisting to an effective distance of less than half the length of the cut fibers.

   The change of direction can be effected by braking the wire on fixed surfaces which may be the wire entry and exit surfaces of the nozzle. The wire exiting the nozzle can be deflected by directing it onto a deflector plate which also serves to force the wire out of the fluid stream.



   The action of untwisting the wire of the nozzle can be likened to a combing action. The pull exerted by the flow of fluid straightens the fibers twisted into a helix, creating a torque that untwists the yarn. A nozzle operating at a speed close to the speed of sound provides sufficient torque to untwist common threads, but it is sometimes desirable, particularly with heavily twisted single-stranded threads, to use a nozzle rotating in the opposite direction. to the twisting of the wire to accentuate the false untwisting torque of the nozzle. Purely mechanical means for applying false twist are known in the section, but are not necessary to achieve the false twist described.

   When the fibers have been untwisted, the turbulence of a high-speed nozzle separates the fibers and transforms them individually into convolutions with fiber tips directed outwards. It is therefore possible to work in a similar manner staple fiber yarns and continuous filament yarns with a nozzle operating at a speed close to the speed of sound, so as to obtain the desired bulky yarn having an outer layer of protruding fiber ends. .

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   Lined yarns can be processed somewhat more easily than single ply yarns because the strands exert a braking action on one another which tends to oppose untwisting of the fibers. This effect can provide some or all of the braking action required to prevent the false untwist region from expanding enough to break up the yarn.

   This can be seen in the case of a doubled staple fiber yarn of the usual type where the elementary strands are twisted in one direction, for example a Z twist, and the doubled yarn in the opposite direction, for example a So twist. twist applied to the fibers of the doubled yarn also twists the strands in the opposite direction, this increase in the twist of the doubled yarn opposes the torque mentioned above, and tends to prevent the fibers from separating too far. long if the twist is sufficiently strong, for example in a strongly twisted yarn, the opposition to the separation of the fibers provides all the necessary braking and braking surfaces must not be used before and after the nozzle. This is true to a lesser extent when the doubled threads introduced into the nozzle are not twisted together.

   But the doubled yarns still exert a braking action which opposes the forces which tend to untwist the fibers of an elementary strand. Therefore two separate single wires can be introduced together in a nozzle and made into a single wire according to the invention with less difficulty than an insulated single wire. When a doubled yarn is composed of continuous filaments and another lined yarn of staple fibers, the continuous filaments also help resist stresses which tend to exceed the draw resistance of the doubled fiber yarn.



   Figure 1 shows a suitable arrangement of apparatus for carrying out the invention. The starting yarn 10 can come from any suitable source, for example a spool of yarn, and can come directly from spinning without an intermediate winding. The wire passes between food rollers 12 and 14 which can be driven so as to advance the wire at the desired speed, which is preferably on the order of 45 to 90 meters per minute but can vary widely. These food rollers are mounted on a pedestal 16. The wire passes through guide 18 on support 20 and into a nozzle supported by air supply pipe 22. The nozzle is shown in section to make its construction clearer.

   The body 24 of the nozzle is hollow and includes a fluid orifice 26, the shape of which is a venturi to create the fluid jet at high speed. A hollow male element 28 is screwed into the body at 30 and ends in a cone 32 projecting into the mouth of the outlet 26 of the nozzle. The wire passes inside the male element, exits through a hole in the cone and is drawn out of the outlet of the nozzle 26 by the fluid stream created by the air entering the nozzle through the pipe 22 The air flow to the nozzle can be regulated by the valve 34 in the supply pipe.

   The wire hole in cone 32 should be of a diameter such that it fits tight enough around the wire so that the wire is sufficiently braked to prevent appreciable untwisting before the nozzle is reached. unless equivalent braking is provided by other means.



   The wire exiting the nozzle is deflected at right angles by a deflector plate 36 mounted on the nozzle near the outlet 26. The deflector plate has the dual purpose of stopping the action of the high speed air jet on the wire. and deflect the wire to prevent unwinding beyond this point. For reasons explained above, the distance between the end of the cone 32 and the deflector plate must be less than the length of the fibers in the treated yarn and preferably such as to limit the false untwisting action of the nozzle to less than half the length of the fibers. Instead of the deflector plate a guide can be used to achieve a similar result. Often sufficient braking can be obtained by tensioning the wire on the outlet surface 38 of the nozzle.

   When the feedback brake is not provided to a sufficient extent by the wire hole in the cone 32, the wire may be introduced into the nozzle at an angle so as to cause it to rub on other parts. of the male element 28.

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   The air current moves at a speed close to the speed of sound to separate the fibers, give them convolutions capable of increasing the volume of the yarn and causing the fiber ends of the yarn to protrude, all as described above. The treated wire then passes through a guide 40 placed below the plate 36 then between a pair of winding rollers 44 and 46 placed on a pedestal 42 and driven at a surface speed slightly lower than that of the food rollers 12, 14 so as to supercharge the nozzle The degree of overfeeding is one of the factors determining the swelling action of the nozzle and generally varies between 5 and 50% depending on the desired effect. The percent boost is the difference expressed as a percentage between the wire feed speed and the wire feed speed after the nozzle.

   Winder rolls 44 and 46 can feed any suitable winding system or one of these rolls can be a winder roll. Different nozzles can be used instead of those shown in fig. 1 to obtain the desired action. A simple form which can be used as an alternative is shown in Figs. 2 and 3 A block of metal 50 is drilled longitudinally to obtain an axial passage 52 for the filo An air inlet hole 54 is drilled at an angle
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 about 45 dà.m'u # .fa # du. block # to remove the passing of the 3-o When a flow of rotating fluid is desired, the air inlet orifice may have a smaller diameter than the passage of the wire and be off-center to intercept the passage of the wire. 'one side as in fig. 3. The connector 56 is welded to the air inlet.

   It is threaded at 58 to secure the air supply pipe 22 of the apparatus shown in FIG. 1. Instead of air other fluids can be used such as carbon dioxide, water vapor or other vapors for special purposes.
The nozzle shown in FIG. 4 has advantages in the two forms already described. Housing 60 may be a standard 1/4 inch T. The thread enters through the guide element 61, provided with a funnel-shaped part 62 for receiving the thread during threading. An appropriately sized hypodermic needle 63 provides a passage for the thread into the nozzle 64.

   The nozzle is in the shape of a conventional venturi tube, the inlet 65 tapering inward so that the opposing sides form an angle of approximately 20 with each other, and the outlet 66 diverging. more gradually so that the opposite sides form an angle of about 7 with each other. The total length of the venturi tube can preferably be 1.3 inches (33 mm), the diverging outlet portion being about 1.0 inch (25 mm) in length. The arrangement of the guide element 61 of the passage 63 and of the nozzle 64 makes the device self-threading when a piece of thread is introduced therein.



   Needle 63 is positioned to extend into the venturi inlet and stop in the venturi throat 670 This adjustment is important for obtaining good results. The mode of adjustment shown is to thread the outside of the nozzle and use adjusting and locking nuts 68, 69. The nozzle slides smoothly into housing 60 until nut 68 rests against it. housing. It is held in this position by springs, one of which is shown at 70. The guide member 61 also slides gently in the housing until the shoulder 71 comes into contact with the housing. It can also be held in place by the spring 70 and other similar springs.

   The advantage of this construction is that it can be easily disassembled for cleaning and the various parts can be rotated to adjust the position of the needle in the venturi throttle. However, one or both parts can be held in place by set screws passing through the housing, or the parts can be screwed into the housing.



   The air is brought into the nozzle through the pipe 72 which is threaded or welded in the T-housing. The air passes through the venturi around the needle 63, the constriction 67 of the venturi being sufficiently large with respect to the needle to allow passage of the required volume of air. A sealing material can

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 be placed in the groove 73 around the element 61 and in the groove 74 around the nozzle to prevent air leakage.



   In Fig. 13, 1 shows a flocking chamber provided with an inlet orifice 2 and an outlet orifice 3 for the thread. Between the inlet port and the outlet port is a free space containing the floc 7. This chamber is also provided with an internal deflector 9 for the air. The air passing through the texture nozzle maintains the floc (or short segments of fibers) in a state of violent agitation o Port 2 is generally provided in a texture nozzle which is provided with an air supply. 4 and an outlet 15 at the base of a venturi chamber 60
The yarn is introduced through the inlet orifice 2 where it is subjected to a jet of high speed air which gives it its texture that is to say which forms swirls and loops as the yarn passes in the suspended floc 7,

   the fibers make their way through the interstices and loops of the yarn and are held and drawn when the yarn leaves through outlet 3 of the flocking chamber 1. The yarn then continues as shown in FIG. 14.



   The process and the products of the invention will be illustrated by the examples which follow, which cannot be taken in a limiting sense.



  EXAMPLE la-
The apparatus shown in Fig. 1 is used to process a 150 denier, 40 filament, 0 twist single yarn formed from continuous filaments of cellulose acetate. This wire is introduced into the nozzle at a speed of 54 m per minute and sent after treatment at the speed of 40 yards (36 m) per minute, ie a supercharging of 50%. The air is introduced into the nozzle at a pressure of 90 pounds / square inch (6 kg / cm2 effective) so as to obtain an effective velocity slightly greater than that of sound and an air passage through the nozzle of 2 , 6 cubic feet (54 L) per minute measured as air (free) at atmospheric pressure and temperature. The deflector plate is 1/8-inch (3 mm) apart from the nozzle outlet.

   The appearance of the untwisted treated yarn is shown in Fig. 5, the filaments have convolutions and the yarn has partially broken off forming a large number of filament loops and loose ends. This thread is not very tenacious.



   Two strands of this wire are introduced together into the nozzle at a speed of 19 yards (17 m) per minute and driven after treatment at a speed of 14 yards (12.6 m) per minute, ie an overfeeding of 36%. The other conditions are the same as above. Fig. 6 shows the appearance of this two-ply yarn after treatment, the yarn having the characteristic fiber loops and fiber ends described above. After twisting the yarn is reasonably tenacious and can be made into a fabric without difficulty.



   Applying the above process but without the baffle plate or with a baffle plate placed one inch (25mm) or more from the nozzle outlet has the effect of completely turning the wire into flock. Applying the process as above but with air pressures of 40 pounds / square inch (2.8 kg / cm2) so as to provide air passages of less than 1.0 cubic feet ( 28 1) per minute, (free air) gives convolutions without appreciable breakage of the filaments, while pressures of 50 pounds / square inch (3.5 kg / cm2) produce the large number of filament loops and ends free described above.



  EXAMPLE 2.-
Using the apparatus shown in Fig. 1, two separate strands of threads are introduced into the nozzle. One strand is # 20 cotton yarn, twist 15 Z turns. The other strand is acrylonitrile yarn formed from 200 denier, 80 filament continuous filaments. The wires are introduced into the nozzle together

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 at a speed of 9 m per minute. Air is supplied to the nozzle at a rate of 90 pounds / square inch (6 kg / cm2 effective) which corresponds to a free air flow of 2.7 feet / cubic (60 1) minute. The appearance of the double yarn after a slight twist is shown in fig 7. The volume of the two strands is markedly improved by the formation of crunodal loops and other convolutions and the cotton fibers stand up which greatly increases the volume. fluffy character of the yarn.

   The cotton strand is elongated by the processing so that it wraps around the continuous filament strand when the yarn is twisted.



   When an attempt is made to process cotton yarn alone under similar conditions without the deflector plate, a yarn is obtained which has completely split and returned to the state of unspun fibers. This is true even under relatively mild processing conditions, for example 50 pounds / square inch (3.5 kg / cm2) of air pressure and 10% boost; the cotton thread is broken up.



    EXAMPLE 3.-
The treatment is carried out in an apparatus similar to that of FIG. 1 A single n cotton 18 acrylonitrile yarn, 18 Z turn spinning twist composed of fibers three inches (76 mm) in length, and 3 denier units. The wire is fed past the nozzle at a speed of 15 yards (13.5 m) per minute and the deflector plate is placed 3/4 inch (20 mm) from the point of deflection formed by the throttled passage. wire in the draft. The air is introduced into the nozzle at a pressure of 90 pounds / square inch (6 kg / ² effective), the dimensions of the nozzle being such as to ensure a flow of about 1 cubic foot per minute (28 1) with an effective speed of the air stream slightly greater than the speed of sound. The appearance of the treated yarn is shown in Fig. 8.

   The volume of the yarn is greatly increased and its surface is covered with annular loops and loose fiber ends, which gives it a fluffy and voluminous appearance and feel.



    EXAMPLE 4.-
Process at a speed of about 100 yards (90 m) per minute with 10% boost, using 50 pounds per square inch air pressure, (3.5 kg / effective cm2) wire. single acrylonitrile n cotton 18, 14 twist Z twist composed of fibers 4.5 inch (11 cm) in length and 3 unit denier. The apparatus is similar to that of FIG. 1 but the nozzle shown in FIG. 4 is used without a deflector plate and the wire guide 50 is placed next to the nozzle so as to rub the wire on the exit face of the nozzle. The appearance of the treated yarn is the same as in Fig 3. The denier of the yarn is increased from 323 to 356.

   The effective volume of the yarn is increased to a much greater extent and a bulky, fluffy yarn is obtained with aesthetic qualities particularly suitable for knits. The changes in the yarn include separation and reorientation of the fibers relative to each other accompanied by sufficient entanglement for the reoriented fibers to stabilize in their new position. The net result is peripheral expansion of the yarn core with a marked increase in the number and length of loose fiber ends and the formation of crunodal loops and other convolutions characteristic of the process.

   Some properties of fabrics prepared from treated and untreated yarn are as follows:
FABRIC PROPERTIES
Before treatment After treatment Weight (ounce / square yard) 7.1 7.2 Thickness (cm) 0.155 0.208 Specific volume (cm3 / g) 6.45 8.55

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 EXAMPLE 5.-
Different yarns are processed in a similar fashion with similar results. The treated threads are all drawn out of the nozzle at 100 yards (90 m) per minute, other conditions being as in Example 4, except as shown in Table 1.

   In this table the indications relating to the yarn such as 50/2 (25Z doubling 4S) 5 inches, 3 dpf in 5 (e) denotes a cotton number 50, a yarn formed of 2 strands in which each of the strands has a Z twist of 25 turns per inch and the strands are twisted together in an opposite direction at a 4 turns per inch twist, the fibers being 5 inches in length and 3 denier per fiber.



  "Rayon" designates the regenerated cellulose yarn obtained by the viscose process.



    "Dacron" and "Orlon" are the trademarks of yarns manufactured by E.I. DU PONT DE NEMOURS AND COMPANY and denote polyethylene terephthalate and polyacrylonitrile yarns, respectively. "Nylon" refers to polyhexamethylene adipamide. The appearance of the treated yarns is similar to that of Fig. 8. However, it is noted that as the length of the fibers increases, the degree of formation of loops in the yarn bundle increases and of course the frequency of the ends. protruding decreases. The extent of the increase in volume can be increased or decreased by varying the overfeeding from the values given in the table, but difficulties may arise for overfeeds greater than 15%.



     TABLE I.



  Preferred processing conditions for making yarns bulky.
 EMI9.1
 
<tb>



  Example <SEP> Treated <SEP> wire <SEP> Supercharging <SEP> Air pressure <SEP>
<tb>
<tb>% <SEP> pounds / inch
<tb>
<tb> square
<tb>
<tb>
<tb> 5 <SEP> (a) <SEP> 18/1 (14Z) 8-10 <SEP> in., <SEP> 3 <SEP> dpf. <SEP> Radius <SEP> 18 <SEP> 50-70
<tb>
<tb>
<tb>
<tb> 5 (b) <SEP> 30/1 (19Z) 3.5 <SEP> in., <SEP> 3dpf. <SEP> Radius <SEP> 5 <SEP> 40-60
<tb>
<tb>
<tb> 5 <SEP> (c) <SEP> 40/1 (222) 6-8 <SEP> in., <SEP> 3 <SEP> dpf. <SEP> Radius <SEP> 10 <SEP> 60-80
<tb>
<tb>
<tb> 5 (d) <SEP> 10/1 (11Z) <SEP> 5 <SEP> ino, <SEP> 3 <SEP> dpf. <SEP> "Dacron" <SEP> 6 <SEP> 60-80
<tb>
<tb>
<tb> 5 <SEP> (e) <SEP> 50/2 (25Z, <SEP> 4S <SEP> ply) <SEP> 5 <SEP> ino, <SEP> 3 <SEP> dpf
<tb>
<tb> (Orlon) <SEP> 6 <SEP> 60-80
<tb>
<tb>
<tb> 5 <SEP> (f) <SEP> 10/1 (15Z) <SEP> 4-6 <SEP> in., <SEP> 2.5 <SEP> dpf.

   <SEP> Nylon <SEP> 6 <SEP> 60-80
<tb>
<tb>
<tb> 5 <SEP> (g) <SEP> 15/1 (14Z) <SEP> 4 <SEP> in., <SEP> 3 <SEP> dpf. <SEP> mix <SEP> of
<tb>
<tb> "Dacron" <SEP> 50%, <SEP> and <SEP> of <SEP> Rayon <SEP> 50% <SEP> 5 <SEP> 50-70
<tb>
 EXAMPLE 6.-
A cotton number 20/1 (total denier 408) 9Z twist yarn, composed of 5 inch (125 mm) 3 denier acrylonitrile fibers, is processed in the apparatus shown in Fig. 1 at a speed of 15.5. yards (14 m) per minute.



  Air is supplied to the nozzle at a pressure of 90 pounds / square inch (6 kg / cm2), the air consumption equivalent to 2.44 cubic feet (69 liters) of free air per minute. The treated yarn is characterized by the presence of long fibers extending from the core of the yarn. These fibers protrude up to 1 inch (25mm) in length resulting in an extremely fluffy cashmere-like yarn.



  In other respects the wire is similar to that of FIG. 8.



  EXAMPLE 7.-
A 2 strand cotton number 27 polyethylene terephthalate yarn was treated at a speed of 15 yards (13.5 m) per minute using an apparatus similar to that of FIG. 1. The strands of this yarn are made of 1 3/4 inch (45 mm) in length, 3 denier fibers, twisted together at an 18Z twist and the twist of the doubled yarn is 11S. The air is brought to the nozzle under a pressure of

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 90 pounds / square inch (6 kg / effective cm2), the flow rate equivalent to approximately 1 cubic foot (28 1) of air per minute. The wire volume also increases well with and without the deflector plate. The appearance of the wire is shown in fig. 9 and with the exception of the two-strand structure, is similar to the wire previously described in relation to FIG. 8.

   In this case, the twists of the fibers and the doubled yarns are sufficient to prevent the false untwist effected by the nozzle from twisting the fibers of the yarn an undesirable distance, and braking on a surface is not necessary.



   An attempt was made to process a single yarn, cotton number 27 twist 18Z, composed of 1 3/4 inch (45 mm) 3 denier polyethylene terephthalate fibers under identical conditions. Without the baffle plate or other means to brake the wire near the nozzle exit the process will not work because the air stream breaks the wire apart.



  EXAMPLE 8.-
The preceding examples have shown that the air current exerts a false untwisting action sufficient to open a large number of stretched threads to the extent required by the method of the invention. However, it is sometimes desirable to enhance the backwash action by using a rotating nozzle.



  This is done by cutting oblique or spiral grooves in the cone-shaped end 32 of the wire guide portion of the nozzle of FIG. 1. For the purposes of the present example, however, the simple torsion nozzle shown in Figs. 2 and 3 is used with an apparatus similar to that of FIG. 1 to process single cotton number 18, twist 18Z yarn composed of 3 inch (76 mm) 3 denier polyacrylonitrile fibers. The air is brought to a pressure of 90 pounds / square inch (6 kg / cm2 effective) to obtain a flow at a speed close to that of sound of 1/2 cubic foot (14 L) of free air per minute.



   Using a nozzle having a 1/16 inch (1.5 mm) wire passage and arranged to apply an S-twist to the treated wire, the wire being braked at 1/4 inch (6 mm) of the nozzle outlet at a distance of 1 inch (25mm) from the air inlet and then fed at 15 yards (13.5mm) per minute, the Z-twist wire gives excellent results and form in number of annular loops and free ends. The yarn is better processed than the same yarn in the straight line air stream of Example 3, although the air consumption is only half. This nozzle has the appearance shown in FIG. 3 when examined upstream at the outlet of the nozzle.

   The air inlet 54 is off-center to the left so as to give the air stream a clockwise rotational motion towards the viewer.



   An attempt has been made to use a nozzle in which the air inlet is off-center to the right which gives a rotational movement in the opposite direction of a clockwise hand to the air stream and applies a Z twist to the wire, but this arrangement has no appreciable effect on the wire. The Z-twist nozzle increases the Z-twist of the wire and prevents the opening action necessary to achieve the desired volume increase.



   Cotton yarns also give excellent results under the above conditions with an S-twist nozzle. Good results are obtained with a single, 18Z twist cotton yarn having an average staple length of 1-5 / 16 inch (33 mm). Due to the short length of the fibers the increase in volume is somewhat less than for the polyacrylonitrile yarn formed of fibers 3 inches (76 mm) in length. When an attempt is made to treat the cotton yarn with the friction point more than one inch (25 mm) from the nozzle all other conditions being equal, the yarn will tear.



  EXAMPLE 9.-
It is observed in Example 8 that the use of a Z-twist nozzle increases the Z-twist of the wire and prevents its opening so that the increase

 <Desc / Clms Page number 11>

 volume mentation does not occur. However, this type of treatment can be combined with the heat setting of the yarn while it is in the over-twisted state to obtain an effect of increasing volume by crimping. A single yarn, cotton number 18, twist 15Z composed of 4-6 inch (100-150 mm) 2.5 denier polyhexamethyleneadipamide fibers can be processed as in Example 8, using a twist nozzle which applies a false twist of about 30 turns per inch. The nozzle was heated to 240-250 C to secure the wire in a crimped state while it is subjected to this false twist.

   A voluminous wool-like yarn is thus obtained with a curly crimp which gives it elasticity. The fibers retain their crimp when separated from the yarn.



   It is often more convenient to heat the wire subjected to false twist on the outside of the nozzle rather than to heat the torsion nozzle.



  The wire guide 18 is spaced a greater distance from the nozzle than in Fig. 1 and a 240-250 ° C heating surface is used to secure the crimp of the wire between the nozzle guide. The yarn is passed through the torsion nozzle without braking it so that the false twist of about 30 turns per inch goes up to the yarn guide. All other conditions being as above, a similar creping volume increasing effect is obtained.



   The method of Example 9 is useful for any yarn composed of fibers which can be heat set to stabilize the creping which has been imparted by the false twist. The treatment gives remarkable results when the fibers shrink due to heat setting. Although the process has been illustrated with reference to yarns formed from staple fibers it is also applicable to yarns formed from twisted and untwisted continuous filaments.



  The process can be combined with treatments according to either of the preceding examples by adding another nozzle to perform a separate phase of false untwist and increase in volume.



  EXAMPLE 10.-
Nylon thread (80/68/0) is passed through a nozzle similar to Fig 8 of US Patent No. 207830609 at the rate of 240 yards (215m) per minute. The nozzle is mounted so as to open into an enclosure partially filled with cotton linters approximately 1/16 inch (1.5 mm) in length (figs 13 and 14). The nip rollers shown in fig. 14 are rotating at 200 yards (180 m) per minute to achieve an intermediate 20% overfeed.



  Feeding is done at 230 yards (208 m) per minute to achieve a net overfeed of 5% and a final denier of 91%. As the calculated denier under these conditions should be 84 the linters increase the weight of the yarn by about 8%. The yarn sample between the flocking box and the nip rollers has the appearance shown in fig. 15. The yarn finally obtained has smaller loops as in fig. 16. With proper magnification, many randomly distributed knots and tangles can be observed. The staple fibers of short length are securely locked in a knot or tangle of continuous filaments of often complex structure; that is, more than one continuous filament and more than one staple fiber contribute to this entanglement.

   Longer fibers can be used instead of cotton linters to illustrate the invention in this example. In general, the flock or linters can vary in length from about 0.1 millimeter, a common length for wood flour, up to lengths normally used for chopped fibers; i.e. about 15 millimeters, although for many applications staple fibers up to 5 inches (125 mm) can be used. In general, relatively short fibers are not held securely and have a tendency to get lost during thread and fabric treatments.

   Normal length fibers in the range 1 (25mm) to 3 inches (76mm) are less easily entangled in broken yarns and therefore tend to modify the yarn to a lesser extent in terms of the number of free ends . The

 <Desc / Clms Page number 12>

 Longer fibers, however, have the advantage of being more permanent in the fabric.



   Any method which tends to entangle the long fibers in the bulky continuous filament yarn can be advantageously used where the fibers are long, for example it may be desirable to pass the bulky yarn through. a loose layer of fibers arranged at random. The contact length and the compressive load on the treated yarn should be balanced to avoid unwanted yarn tension tending to cause breakage, but should be sufficient so that the filament loops can surround the entangled chopped fibers and large loops can occur. deform to take the shape shown in FIG. 17.



  The protruding fibers and elongated loops can be temporarily held in place by a sizing to improve weaving results and reduce the tendency for snagging in the finally obtained fabric.



   Where a more stable yarn is primarily desired, short fiber segments such as Solka-Floc wood cellulose can be used with good results. (* Product of Brown C, 150 Causeway St., Boston 14, Massachussets) Very short fibers tend to escape control to some extent but increase the stability of marginal yarns to a sufficient extent to allow for beaming, on shuttle, weaving or knitting. The volume of the finished fabrics can be improved even after the disappearance of the short fibers due to the empty spaces they leave behind them.



   Likewise, the bulky yarn can pass through a liquid fiber slurry. When the fibrous material is well dispersed, of the appropriate length and concentration, the thread comes out of the slurry having the appearance of a pipe cleaner and its weight is increased by 50% or even more. Again, tension can be applied to the yarn to lock most of these fibers in place.



  Heavily loaded yarns, however, tend to lose some of the loosely attached fibers, and these fibers can be blown, rubbed or stirred and returned to the slurry.



   The following experiments illustrate forms of the invention where two different yarns are used, one of the two being relatively bursting and the other relatively non-bursting.

 <Desc / Clms Page number 13>

 



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 <Desc / Clms Page number 14>

 EXAMPLE 18.-
A strand of "Orlon" is treated to obtain a 32/2 n cotton yarn combed system with a single twist 8 Z yarn and a combined 4 S twist, composed of a mixture of 80% of loose fibers of 2 unit denier and 20% high shrinkage fiber. This wire passes vertically through an ordinary 1/4 inch (6 mm) diameter T-shaped glass tube. Air at 10 psig (0.7 kg / cm2) pressure is directed through the horizontal leg of the T-tube to move the wire out of its vertical path. The wire passes through the tube at approximately 60 yards (54 m) per minute. This gives a fluffy yarn having a soft and bulky texture.

   The air pressure in the tube can vary from approximately 10 to 100 psig (0.7 to 7 kg / cm2). It is difficult to determine the speed in the tube, but when the air is pressurized in the upper part of the pressure range, its speed of contact with the wire is of the order of the speed of sound. Yarn treated in this way has fewer loops and coils and normally very few broken filaments compared to the products in the examples where a high speed nozzle is used with yarns containing a brittle element. The free ends protrude much more from the wire bundle after treatment than in the starting wire.



   While the examples illustrate the use of acetate fibers as a brittle or burstable member, it will be appreciated that filaments of other materials can be used more or less directly in the examples. Choosing a
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 filament for this purpose depends on its tendency to break. sol'as-, 11 a> - t: 1,, 0 .n "'. of the high velocity jet of the nozzle. It has been found that this tendency can be determined by a flexural strength test which essentially consists of bending the wire 1800 repeatedly over a smooth metal wire and under a determined tension. The number of cycles required to break the sample is taken as an indication of its flexural strength.

   The test is performed by conditioning the filaments for at least 16 hours in an atmosphere of 70 F (21 C) at 65% relative humidity. In general 21 filaments are tested together and the number of cycles required to determine the breakage of 11 filaments is accepted as the test result. The voltage applied to the sample can be 0.15, 0.3 or 0.6 g / denier depending on the fragility of the sample. It is desirable to choose a weight factor which gives a test duration of at least 50 cycles and at most 5,000 cycles. The 0.6 g / denier load is satisfactory for most textile fibers.

   The order of magnitude of the flexural strength of fibers generally used under a load of 0.6 g / denier is as follows:
Flexural strength
Nylon and "Dacron" 1.0000000
Rayon 3.000
Acetate 300
Polystyrene 10
Glass 1
In general, with other factors held constant the more stubborn fibers can be stabilized by using a slower processing speed in the nozzle so that successive individual lengths of fibers are exposed to the bending action of the air exiting from the nozzle. nozzle for a longer time or by using higher air pressure in the nozzle which gives a more violent bending action in the nozzle outlet.

   An example of the first type relates to rayon which is treated at 20 yards / minute (18 m / min.) To obtain a product similar to that obtained with acetate at 200 yards / minute (180 m / min) (approximately in inverse proportion to the flexural strengths given in the table).

 <Desc / Clms Page number 15>

 



   For a given fiber composition a wide range of flexural strengths can be achieved by changing the orientation and / or degree of crystallinity. Normally nylon and "Dacron" are much more tenacious to be broken by the action of 'a texture nozzle. If, however, they are prepared in the state of low orientation and high crystallinity, the flexural strengths can be reduced to a few hundred or a few thousand cycles. The molecular weight indicated by the relative viscosity in a suitable solvent also plays an important role in determining the tenacity of the fibers.



  "Dacron" fibers prepared from a polymer having a relative viscosity of about 12, even though they are internal and crystallized by the operations of a normal process exhibit flexural strengths in this same lower range. (100 to 10,000). In general, a filament having a flexural strength time of less than 10,000 cycles can be used in place of acetate in the examples.



   CLAIMS. the bulky yarn comprising a large number of staple fibers twisted together, these fibers being wound in spirals, loops and swirls at intervals distributed randomly along their length, and the surface of the yarn having a large number of annular loops and ends of projecting fibers distributed irregularly along the surface of the yarn.



   2.- Bulky yarn, characterized in that it comprises a large number of chopped fibers twisted individually on themselves at intervals distributed randomly along their length and at an irregular spacing on different fibers, the yarn having a fluffy surface composed protruding fiber ends and crunodal loops.



   3.- Bulky yarn formed of twisted staple fibers, characterized in that it comprises a large number of annular loops and projecting fiber ends, distributed regularly along the surface of the yarn, and has a large number of convolutions of fibers, irregularly distributed in the structure of the yarn and giving a lateral inter-fiber spacing increasing the volume of the yarn.



   4.- Bulky yarn composed of at least two strands of twisted staple fibers, characterized in that it has a large number of annular loops and protruding fiber ends, irregularly distributed along the surface of the yarn and a large number of convolutions of fibers irregularly distributed in the structure of the yarns and ensuring a lateral inter-fiber spacing increasing the volume of the yarn.



   5.- Bulky yarn having a fluffy surface formed by a large number of protruding fiber ends and comprising a large number of crunodal loops and other convolutions irregularly distributed in the structure of the yarn, creating an increasing inter-fiber lateral spacing the volume of the thread.



   6. Bulky yarn having a fluffy surface formed by protruding staple fiber ends and a core structure comprising essentially continuous filaments individually wound in a spiral, loop and swirl at irregular intervals along the filament, and charac- terized by the presence of a large number of crunodal loops.

** ATTENTION ** end of DESC field can contain start of CLMS **.


    

Claims (1)

7.- Bulky yarn having a large number of protruding loose fiber tips and enhanced bulk created by crunodal loops and other convolutions of fibers distributed throughout the yarn structure, the fibers of the yarn being twisted together to hold the structure in place- 8.- Bulky twisted yarn with a large number of fiber ends protruding from the surface and a large number of staple fibers, individually looped around themselves at irregular intervals along their length, and distributed <Desc / Clms Page number 16> irregularly on different fibers, these loops almost completely disappearing when the thread is untwisted and passed. 90 - A method of making bulky yarns having a protruding layer of filament ends, characterized in that a twisted yarn is passed through a fluid nozzle at high speed and the yarn is prevented from losing an appreciable degree of weight. its twisting until it reaches the nozzle, a false untwist is applied to the wire using the nozzle, the wire is projected at a speed close to the speed of sound to form convolutions in the filaments of the wire and create a large number of protruding filament ends, the yarn is removed from the nozzle after a path of a length less than the length of the shortest filaments and the yarn is twisted near the nozzle to maintain the convolutions. filaments and the ends of the filaments in place. 10.- A method of treating a textile yarn, characterized in that a layer of convolutions and protruding filament ends is formed around the yarn by subjecting it to a high-speed air jet. llo- A method according to claim 10, characterized in that the nozzle applies a false twist to the wire. 12. A method according to claim 10, characterized in that the air jet comes into contact with the wire at a speed close to the speed of sound. 13. A method according to claim 10, characterized in that the air jet breaks some of the filaments. 14. A method according to claim 10, characterized in that the yarn contains cut fibers, and in that the air jet projects cut fibers. 15.- The method of claim 10, characterized in that the wire is deflected against a fixed surface adjacent to the entry point of the nozzle and deflected again on a second fixed surface at the exit point of the nozzle, the distance between the two points of deviation being less than the average length of the cut fibers. 16. A method according to claim 10, characterized in that two independent strands are introduced together and mixed to form a single strand in the nozzle, at least one of the strands being composed of chopped fibers twisted together. 17.- A method of making bulky yarn having a layer of protruding fiber ends, characterized in that a yarn composed of several strands of cut fibers is introduced into a nozzle at high speed, the fibers of each strand being twisted together in the same direction, and the strands being twisted together in the opposite direction, a false untwist is applied to the yarn using the nozzle, the yarn is projected at a speed close to the speed of sound to form convolutions in the fibers and creating a large number of protruding fiber ends and crunodal loops, the yarn is removed from the nozzle after a path in the nozzle less than the length of the fibers, and the treated yarn is sent, the twists of the fibers and the strands being sufficient to prevent the false untwisting action of the nozzle untwisting the fibers of the yarn over a distance greater than half the length of the fibers. 180- A method of making a bulky yarn having a layer of protruding filament ends, characterized in that a yarn is passed through a high speed air nozzle to form vortices and loops therein. passes the yarn in this state in contact with free fibers, then the yarn is sent under tension. 190- A method according to claim 18, characterized in that the fibers are floc 0.1 to 13 mm in length. <Desc / Clms Page number 17> 200- The method of claim 18, characterized in that the fibers have the form of chopped fibers whose length can reach 5 inches (125 mm). 210- A method according to claim 13, characterized in that the flexural strength of an element of the wire is less than approximately 10,000. 220- The method of claim 13, characterized in that the flexural strength of an element of the wire is less than approximately 300. 23. A method according to claim 18, characterized in that the increase in the weight of the yarn due to the entrainment of fibers can reach 50%. 240- The method of claim 10, characterized in that the yarn is composed of a large number of strands of cut fibers, the elementary strands being twisted in one direction, and all of the strands in the opposite direction.