CS209403B2 - Method of ammeliorating physical properties of fibres threads or yarn processed in textile flat bodies and device for executing the same - Google Patents

Abstract

1,140,030. Stretching fabrics. RADUNER & CO. A.G. 28 Feb., 1966 [8 March, 1965; 31 March, 1965], No. 8687/66. Heading D1S. Apparatus for width-wise, stretching fibrous sheet material 10, e.g. a woven fabric, comprises a pair of meshing grooved rolls 20, 22, at least one of which is driven, and means 44 to prevent the material 10 contracting in the width-wise direction in the region of the rolls 20, 22. The lands 36, 38 of the rolls 20, 22, respectively, are staggered with respect to each other. The means 44 comprise elastic rings, preferably elastic tubes filled with a pressure fluid, providing in the end grooves 40 of the roll 20. Two pairs of rolls (20), (22), Fig. 1 (not shown), and (30), (32) are preferably provided and are located between helically threaded spreader rolls (14), (28), (34) or bowed spreader rolls. Fabrics treated by this apparatus may be composed of yarns or fibres of natural or regenerated cellulose, cellulose derivatives, e.g. cellulose acteate, protein fibres, e.g. wool or silk, polyamide, acrylic or vinyl polymers or copolymers, polyesters, polyurethanes or mixtures of different fibres. The stretching treatment may be carried out at any stage during the finishing of the fabric, e.g. it can be carried out before, during, between or after de-sizing, washing, bleaching, dyeing, swelling or liquid, mechanical or heat treatments. Preferably, the fabric is plasticized prior to stretching which is carried out at a temperature of -10 to 250‹C. The apparatus stretches narrow zones of the fibrous material by applying stretching forces longitudinally of each zone to short lengths of material in such a manner that the elongation of the fabric in each short length is at least 10%, prefarably at least 50%, of the elongation at which the fabric breaks and the velocity of elongation in each short length is at least 10% per second, preferably 50% per second.

Description

(54) A method for improving the physical properties of fibers, yarns or yarns processed into textile sheets and apparatus for performing the method.

The present invention relates to a method for improving the physical properties of fibers, yarns or yarns of processed textile fabrics by stretching the articles in small areas by deflecting the sheet from its plane while retaining its dimensions, wherein the stretching forces are applied at any point in time only within a narrow strip perpendicular to the textile zone in the form of numerous small areas, the forces causing stretching only act in the stretched direction, the force. the elongation causing at least 10% elongation of this material upon elongation in the elongated direction, the limit and molecular cohesiveness of the fibrous material is reduced to elongate and, after elongation, is restored to at least its original state; the invention also relates to an apparatus for carrying out this method.

It is known that by stretching or drawing out yarns, threads or other fibrous textile materials of natural or synthetic polymers during or immediately after the spinning process their mechanical properties, orientation, density distribution on the cross-section of the fibers formed can be controlled in a controlled manner. etc.

Further, it can be seen from the literature that other effects of various kinds can be achieved if the yarn, thread or other fiber textile material is processed by drawing on conventional devices. For example, · Textile Research journal 31 (1961), p. · 550 · describes how treatment with pre-stressed amino-plastic condensates will result in less strength losses in cotton yarns than when the same treatment is carried out without tensioning. . In American Dyestuff Reporter 54 (196 = 4), p. 25, it is noted that mercerization of the yarns under strong stretching produces particularly intense mercerization effects. In Chemie 55 · (.1942),. p. 12, it is found that the regenerated pulp fiber cables achieve a significant increase in their tensile strength by punching 15%. Polyamide fiber drawing processes are described in Pummerer's book: "Chemische Textilfasern, Filmen und 'Folien", 1953, p. 685.

All these effects were possible; as mentioned, only be achieved with the fibrous textile material. In many cases, however, it would be beneficial if these effects could. only when the fibrous materials have been processed in the form of textile sheets.

Therefore, the invention is based on the task of finding a method in which the necessary change in the physical properties of a textile material occurs first when the fibrous textile material has been processed to form a sheet.

This object is achieved by the method according to the invention, in which the fibers, threads or yarns of synthetic polymers and / or wool or cellulose are pulled in small areas at a rate of at least 10% / s and this stretching is combined with the preceding or following fiber processing. yarns or yarns to stabilize their configuration.

Methods are already known in apparatuses with which textile fabrics can be pulled out. However, these processes and devices cannot achieve the elongation necessary for the intended change in the physical properties of the fibers in the sheet. In fact, in conventional pulling procedures, long pulling sections are used, i.e. a large distance between the points of application of the pulling force. In the tensioning frame, the tensioning section corresponds, for example, to the width of the goods. In the mercerizing machine, the withdrawal section corresponds to the length of the working section on which the web of goods is processed in this machine. In this case, the stretching in such devices is not evenly distributed over the entire surface, the formation and the yarns being drawn along their length. Their more easily extensible areas will stretch extensively, the heaviness of the extensible areas will remain virtually unchanged. In addition, the elongation in the vicinity of the forces of the stretching force is stronger than at a greater distance from these points. This uneven pull-out also implies the impossibility of achieving elongation up to < &apos; Indeed, the more easily stretchable and heavily drawn portions of yarns and fibers break before the other portions are sufficiently stretched. In addition, such devices require a high expense, which, if further escalated to achieve the desired properties, would all the more likely result in the failure of the goods.

It is therefore a further object of the invention to provide a device by means of which the method according to the invention can be carried out. This object is achieved by a device characterized by at least one pair of interlocking groove or comb rollers, of which at least one is driven, and by means which act in the gap between the rollers and / or adjacent thereto, and it avoids strangulation of the sheet in the pulling direction in the region of the comb rollers, wherein the devices acting in the gap between the rollers consist of rings of elastic material interposed between the ridges formed by the ribs in the end section of the rollers.

There are already known devices which are intended for processing textile materials in the form of a band and have rollers with a wavy longitudinal cross-section or with helical projections. Such devices are disclosed, for example, in Simon and Vojtek .: "Refining Machines and Refining Processes in the Textile Industry", SNTL 1960, p. 188. One of these devices is illustrated in Figure 166 on the same page. This apparatus is a machine that has a wave-like cylinder ¹ · longitudinal cross-section. The individual rolls are spaced apart from one another when viewed in the direction of movement of the goods zone so that there is no gap between the rolls in which the fibers of the sheet can be drawn. A zone of goods which runs first through one and only then through the other of the trains, which lie on both sides of the zone of the goods, is pushed into the grooves of the respective cylinder by the force of the zone. over the protrusions of the comb roller. This loosens the fabric structure and, as a result, the fabric becomes softer and more supple. However, the stretching of the substance required for carrying out the process according to the invention cannot be achieved with such machines.

It has been found that in the case of fibers or yarns already given in the form of a textile sheet, the physical properties, in particular the mechanical strength, can be improved if the fibers substantially in the direction of their axis with at least a temporary cancellation of the processing the fiber assemblies are subjected to at least one-stage drawing in small areas. In this case, the pull-out forces can act only within the narrow strip of the textile formation and practically only in the direction of the pull-out fiber assembly.

Processing refers to the normal state of the warp and weft in the fabric, where both the weft and warp are undulating along the length of the weave. When machining is canceled, the wefts in the fabric are straightened while the warp curves increase. The term pulling in small areas means that the points of application of the forces exerted within the strip of stretching lie very close together. This kind of pulling must be used so that each area of the fiber being just drawn has exactly the same elongation

The pull-out should be at least 30% but preferably at least 50% of the pull-out when the textile web breaks down the pulling direction, the pulling speed being at least 10% / s, but preferably at least 50% / s. During the pull-out, the intermolecular continuity of the pull-out material can be reduced and at least restored to its original state after the pull-out. The sheet can also be pulled out in a gentle manner over the entire surface. The extraction can take place practically parallel to the fiber axis, preferably even in the fiber axis. This requires that within the surface to be treated, the pulling out is practically only in the direction of the pulled fiber system, while in the direction of the second fiber set, at most a small elongation can occur, compared to the pulling effect in the stretching direction, i.e.

F * η

stretching. Therefore, in addition to the width of the stretching section, the drawing area must be small. As mentioned, an elongation of at least 30%, but preferably at least 50% of the elongation of the respective sheet-like structure at break in the elongation direction must be achieved. In addition, the elongation must be uniform over the entire yarn surface.

The drawing speed must, as said, be high and should be at least 10% / s, preferably 50% / s or more. Pulling out must therefore occur almost suddenly. In fact, as the pull-out speed increases, the tensile breaking load of most fibers increases in higher velocities, but the elongation at break is not reduced accordingly, cf. Journal of the Textile Institute 50 (1959), pp. 41-54. for example, by reducing · and controlling · the mechanical forces exerted, the pulling forces can be better controlled and differentiated, and as a result, greater elongation can be achieved with greater reliability than if working · normal! extraction procedures. The very high drawing speeds also limit the sliding of the individual yarn components one after the other, so that effects that are obviously not achievable at a drawing speed of 50 to 100 times less can be achieved.

As a result of the uniformity of pulling, pulling can be achieved up to near pulling up at break The pulling speed can be increased up to 10 to 1000 times the speed achievable by conventional methods on sheet bodies with the same pulling intensity. Due to the small dimensions of the pull-out area, the pulling force exerted in many cases is only a fraction of the force required in conventional pulling procedures.

Particularly good results are achieved • n ° BL · if the proportions · --- and BD- are as close as possible to their maximum, where D is the percent elongation achieved, BD is the elongation at break in the extracted direction, BL is the breaking load at the speeds and pulling conditions used.

When used as a device for carrying out the process according to the invention to induce a small-scale pull-out across the web of comb, intervening rolls, the pull-out can be controlled by either limiting the depth of roll penetration or by maintaining a constant pressure value. the comb rollers are pressed against the textile web lying between them or by a combination of both. As a rule, the comb rollers will not touch their entire length, otherwise it would not be possible to vary the depth of their penetration and thus the degree of retraction. it is also expedient to hold the edges of the textile band with any suitable device to prevent the edges of the fabric from tilting towards the center of the band and due to the tension acting across the band, thereby pulling on both sides of the textile · The bandwidth was * smaller than in the middle. Holding regions can be achieved in different ways.

For example, the textile web can be guided in width just prior to meeting, with the comb rollers and possibly also after encountering them, with the aid of known edge guiding devices, or any expanding device acting against deflection of the fabric edge towards the center thereof. A very simple method execution region consists in, • that the at least one _of: a ridge, two intermeshing rolls, and in those two regions in which the running region of the textile band is inserted into the grooves of the ribbon or other elements suitable · shape , which, due to the high friction resistance, prevent the edges of the textile zone from sliding laterally towards its center or by contacting the edges of the textile zone by contact with the ridges of the opposite comb roller.

Conveniently, the band-shaped bodies consist of a material which is elastically compressible, for example rubber or a puncture rubber, of resiliently compressible plastics, which may optionally contain vapors, i.e. in the form of a foam, or · may also consist of combinations of resilient and less resilient material. The cross-section of these bodies can be rounded, angular or can be adapted to the shape of the groove of the comb roller, or have a shape which, for example due to the cavity treatment, combines a certain compressibility with the highest resistance to lateral slip.

The lateral deflection of the edges of the textile zone can be largely counteracted or even prevented by the shape of the comb roller combs and their mutual distances. Close-to-back ridges and ridges that do not have a round but rather angular cross section prevent lateral sliding particularly well, but their edges must not be cut into the material.

Particularly uniform effects are obtained for many fabric structures when interlocking comb rollers are used which contact at most individual locations, for example at points located at and near both edges of the textile zone, and whose combs have such combs. in that the proportion of the yarns or fibers to be drawn which are adjacent to the rollers is at least as large as that which has already been pulled out between the ridges, preferably at least two stages.

The surface of the comb rollers may consist of metal or other material which, under the conditions of extraction, retains virtually completely its shape and is at most only slightly compressed during extraction, i.e. preferably has a hardness of at least. 100 ° Shore A. It is important that the sliding resistance of the surface material has a favorable value, especially compared to the water-containing material. The friction values of about 0.2 to 0.7 have proven to be most favorable for the damp textile material on the respective roll material.

If the pulling is to be retail, the ridge spacing of the comb rolls must be at most 1/10, preferably at most 1/20 of the width of the textile band, i.e. the pulling sections must be at least ten or twenty times smaller than normal; drawing by pulling on both edges of the textile band so that this distance will be at most 10 cm, preferably at most 5 cm. In a preferred embodiment, the spacing of the comb roller combs is 1 to 2.5 cm, but in any case not more than 3 cm.

If the extraction is carried out in several stages, different shapes and / or distances of the ridges may be used in the individual stages. Successfully used were also modifications in which three of the same intermeshing comb rollers carried out a two-stage pull-out, or in which several small comb rollers occupied) into one larger cylinder. For each multi-stage extraction between comb rollers, it is important that the sheet is uniformly smoothed over the entire width of the intermeshing comb rollers, or is aligned by means known per se, such as spreader rollers, with spiral rollers after each pass · Spacers, etc., i.e., that the longitudinal folds of the rollers formed are pulled into the surface before the textile web enters the next pair of comb rollers. This guarantees, on the one hand, a uniform second extraction stage and, on the other hand, it is achieved that the rolls of the second pair of rolls do not contact the same with the textile material. places as · first pair. comb rollers.

Before stacking or winding of goods pulled between racks. the rollers must, of course, also be stretched to the surface so that no wrinkles are fixed during winding, or the pulling effect is not damaged.

The textile material used in the process according to the invention is a textile sheet, in particular a woven fabric, possibly also a stripe knitted fabric mainly with inserted wefts or a web with transversely oriented fibers. It may be composed of fibers or yarns or threads consisting of fibers of natural or regenerated cellulose, of cellulose derivatives, for example of cellulose esters or acetates, of protein fibers, of wool, of silk, of polyamides, of acrylic or vinyl polymers, of mixtures of polymers or copolymers of acrylic or vinyl compounds, of polyesters, polyurethanes or of mixtures of different types of fibers. If special emphasis is placed on pulling parallel to both fibers, a yarn whose twist approximately corresponds to the twist of the twisted yarns, but with the reverse sense of rotation) can be used to produce the woven fabric at least in the extracted direction.

The textile material according to the invention may comprise refining agents such as dyes, coloring or coloring pigments, agents suitable for wetting fibrous material, intermolecular reducing agents, such as swelling agents, and friction-modifying agents. Pulling out can be. thus, for example, in the presence of swelling agents and friction-enhancing agents between the individual fibers, such that slip between the fiber macromolecules is promoted, but the slip of the fibers in succession is reduced.

As mentioned, the pulling process of the present invention can be carried out by releasing the intermolecular association within the fiber to which the textile material can, for example, contain agents causing weak to strong swelling, or the bond between the macromolecules can be released by physical · Means such as heat. After the drawing-out process, if necessary also during the drawing process, the intermocular continuity of the material is restored at least to its original state.

The pull-out treatment may be carried out at or below room temperature, in or below it. In certain cases, it may be desirable that mechanical stress-inducing stresses do not occur, for example, in fabrics exactly parallel to the fiber systems. In this case, it is possible, for example, in the case of small-scale pulling in the weft direction by the comb rolls, to change temporarily between the warp and weft yarn system from 90 ° to an angle of, for example, 75 to 85 ° or, the pulling device can be designed such that it is carried out by pulling at a constant or variable angle with respect to the pulling system of fibers.

It has been shown that higher pull-outs can often be achieved if the pull-outs are not carried out in one stage but in several wells or repeatedly. These stages may follow one another directly, for example if several identical or different pull-out devices acting on the same fiber assembly are used in sequence, or it is possible to carry out some pull-out steps between the individual pull-out stages. ·. well-known · textile · processing.

The drawing process according to the invention can in principle be carried out at some stage of the refining process, i.e. between the weaving process and the confection process. They can also be carried out before desizing, washing, bleaching, dyeing, swelling wetting, for example by treatment with lye or pulp fibers by finishing, · mechanical deformation

299403 and 10 mi, etc., if any, between them. Typically, however, the drawing / drawing process will be carried out prior to any of the fixation procedures which have - in the footer - some configuring of the sheet, possibly the yarns and fibers, or - stabilization of the dimensions due to the heat treatment, or - compressive - precipitation - or - wetting to be retained for the purpose of - further processing of the material or even its use in a ready-made treatment. For example, in the case of pulp fibers, the self-drawing after permanent pulping is much less effective.

Depending on the purpose to be attained, it is advantageous in many cases that the effects caused by the small-stretch drawing, for example the fiber-yarn configuration, are permanently fixed by a fixation treatment. In other cases, for example when the ultimate breaking load of a material is to be increased or its dye capacity, the material can be restored to its original state by treatment completely or partially. The relevant examples will be given below.

The invention can achieve the following effects:

Above all, an increase in the mechanical strength, in particular the breaking load; considerable -to complete transfer of processing -from the fiber system -to the second -fiber system -without substantial- or effort-to-flat-end; [0004] The process known in the art, without exception, makes a considerable effort and, with a considerable increase in strength, for the pulled-out fiber system, the strength at best remains the same, and this transfer of processing is according to the selected conditions - transient procedure -or can be fixed. Examples of such effects are an increase in elasticity in the fiber system to which the processing has been transferred, better roughness of the textile fabrics in which the processing according to the invention has been transferred to improve the weft strength, the plasticizing printing effects based thereon that the processing has previously been substantially transferred from one fiber assembly to the other, and then the processing is substantially transferred back to the first fiber assembly; granularity - for dye - for thermoplastic fibers in the fabric. increase - flexibility; reduction of elongation-at-break; In fibrous mixtures, insensitivity occurs in the extended direction. - persistent - deformations associated with - considerable area gain; - increased saponifiability of at least - the surface of thermoplastic fibers, such as those of acetylated pulp; achieving changes in the fiber surface by surface embrittlement of the fibers and subsequent drawing in small areas, thereby causing fraying or cracking of the fiber surface; embrittlement of the surface is understood to mean a reduction in the elongation at rupture of the inner fibrous layers, or an increase in the elongation at rupture of the inner fibrous layers, whereupon the fibrous material undergoes a low-stretch drawing which is greater than the elongation at break of the outer fibrous layer; less - than elongation - when the inner fiber layers break; - curling effects by maoioiblastic drawing, in particular - between ridge rolls at elevated temperatures, in particular between heated metal ridge rolls, the temperature of which is close to the installation temperature of the respective thermoplastic fiber-material, preferably followed by wet processing at - elevated temperatures, possibly also dyeing and fixing.

The pull-out process according to the invention can also serve to loosen sticky fiber crossings in the textile-shaped shapes. In particular, the fact that, according to the invention, the processing of the drawn-out fiber system is abolished because of the fact that the bonding points between the two fiber systems are strongly influenced by this, is contributed to this. diminishes - by penetrating - removing - the mutual encirclement of the fiber systems. Conventional post-up pull-out procedures are not possible or are only possible because the processing at best achieves a maximum of a certain equilibrium. because, in the case of glued fiber crossings, the friction between the fiber systems when pulling with large pull-out sections - and very large surfaces - and the pull-out - on the pull-out sections - is therefore very uneven.

The pull-out process according to the invention can further be used for the production of sheet-like extensible shapes precisely in advance. For example, for the reinforcement of artificial materials - by textile - surface formations - the ductility of the plastic material - and the ductility of the - surface - shape to be used for the reinforcement - need to be precisely matched to each other, but only to the extent of reinforcing effects. at all - to achieve. However, the extensibility of the planar formation over the entire surface must be uniform. As a result of the above facts will not get. conventional pull-out procedures or even uniformly sufficiently strong pull-out to meet these requirements and also pull-out cannot be controlled as accurately as possible. operational reliability achieved - predetermined pulling.

The small drawing according to the invention can also be used to achieve the effects of drawing the fibers in a strongly swollen state, which can usually only be achieved during yarn processing. For example, cotton can be treated with merceric lye at a concentration of merely or strong acids and can be subjected to a small-scale drawing before and / or during swelling ^; and / or thereafter. Due to the fact that the pulling-out proceeds parallel to the axis of the yarn or fibers, effects are obtained which cannot be achieved with the usual processes and apparatus but only in the processing of individual fibers or yarns.

Especially for fibers with relatively high swelling, such as cellulosic, it is expedient to carry out the pulling-out process when the textile material is at least slightly swollen, for example wet to wet. As already mentioned, the small-scale drawing according to the invention may take place during some periods of refinement of the respective textile material, preferably before fixing, in order to more or less permanently fix the dimensions of the textile material and / or the yarn and fiber configuration.

Polymeric bodies can be applied or introduced, for example, in situ by polymerization or by polyvinyl chloride, causing the reactive functional groups of the textile material or individual components to be applied or introduced prior to the small-scale drawing, during or between such drawing operations. between, molecular chains or generally chemically modify, mechanically pre-shape or induce changes in the surface of the fibers or their components.

The retail processing according to the invention is preferably carried out over the entire area, but can only take place locally.

Examples are given below to illustrate the process of the invention and some of the achievable effects, but it cannot be claimed that they are administered in an exhaustive manner or that the invention is limited thereto.

When, according to the invention, sheets are formed comprising at least partially pulp fibers, for example natural fibers such as cotton, flax, jute, regenerated pulp in the form of continuous or layered fibers, including fibers of particularly high wet strength or high modulus of elasticity; if, directly, then or sometimes at a later stage, to undergo processing, such as dimensional stabilization, enhancement of wet crease recovery, or dry, scouring and abrasion properties, irreparable fixation of finishes, or mechanical deformation, which results in an increase in the intermolecular continuity of the pulp, in particular the formation of bridges between the pulp macromolecules, whereby the tear and tear strength losses, when measured on an Elmendorf instrument, result in pulp fibers in the pulled direction mn by less than that of the same material not drawn according to the invention.

In the foregoing description and in a number of the following examples, it is pointed out that the yarn processing which runs in the direction of the pulling force is completely or virtually completely abolished. By this is meant at least a temporary transition of the wavy course of those yarns which are partially wrapped in the fabric bundle and which are arranged parallel or approximately parallel to the pulling direction, into a substantially stretched, i.e. totally or approximately rectilinear, course. in the second direction, for example to the first perpendicular direction, generally increases somewhat.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be explained by way of example with reference to the accompanying drawings, in which: FIG. 1 schematically shows a side view of the drawn fabric web; FIG. 2 is a cross-sectional view according to arrows 2-2 of FIG. 3-3 of FIG. 2.

The device according to the invention is based on at least one pair of intermeshing, comb or groove rollers 20, 22 and 32. At least one of the comb rollers 20, 22 and 30, 32 is driven in each pair. The ridges of the comb rollers 20, 22 are formed, for example, by ribs 36, 38 between which there are gaps forming grooves or grooves 40, 42.

In front of each pair of comb rollers 20, 22, 30, 32 and downstream of the last pair of comb rollers 30, 32 are spacers 14, 28, 34 formed, for example, by a cylinder, whose sheath has oppositely directed helical formations 18, 18.

The rack rollers are equipped with a shaft

Each driven comb roller 20 has a gear wheel 24 on the shaft 26. 24. Rings 44, for example of elastic material, are inserted into the outer grooves 40, 42 of one of the pair of grooved rollers 20, 22. According to another embodiment, the rings 44 have the shape of a hose and are filled with a pressurized environment. These rings 44 are resiliently defensible in the region between the rollers 20, 22 by the elevations of the second roll engaging the grooves of the rings 44 containing the rings.

A friction-reducing layer is expediently disposed between the rings 44 and their abutment surface in the grooves 40, 42, which, when the rings 44 deform, allow their length to be compensated within the grooves 40, 42. It is preferable to place the rings 44 in the grooves 40 of the driven roller 20.

The device shown is particularly suited for the controllable pulling of textile sheets in small areas across the textile zone. In the apparatus of FIG. 1, the longitudinal tension acting on the textile zone 10 unwound with the loops 12 need not be greater than necessary to avoid folds in the zone 10 by the pairs of comb rollers 20, 22 and 30, 32. As a rule, only a slight stress in the length direction is required. At least one of the comb rollers 20, 22 and, 30, 32 in each pair is driven, and these driven rollers also cause the conveyance of a textile zone 10, for example a fabric, between the comb rollers 20, 22 and 30, 32. The force across the zone 10 is based on the deflection of the textile zone 10 from its plane up and down the ribs 36 and 38 of the comb rollers 20 and 22 and is therefore not derived from the forces acting in the longitudinal direction of the textile zone. This is fundamentally the difference between the action of the bent spans, in particular the spiral risers 14, 28, 34, in which the width expansion effect derives from forces acting parallel to the longitudinal direction of the textile zone 19 and its direction of travel; these forces the textile zone 10 to run on the spacers, thereby allowing a wide expansion effect.

The device shown is not only suitable for special pulling effects on textile bands, but also for pulling out any web material. Of particular importance here is the device for retaining both edges of the material band. The compressible and expandable rings 44 allow not only easy adjustment of the edge guide to a given width of the textile band 1П, but also allow the depth of penetration of the two comb rollers 20, 22 to be varied; 39, 32 of a single pair within wide limits and thus also vary the degree of withdrawal, which is primarily dependent on the depth of penetration of the rollers. The capability of the rings 44 is based both on the use of the compressible and stretchable material of the ring 44 and on the cross-sectional shape of the rings 44, which ensure effective retention of the edges of the textile zone 10, whether the distance between the comb rolls 20, 22; 30, 32 or relatively large.

Example 1

The cretone with 17/17 threads per cm of ethylene glycol terephthalate staple yarn was as follows after washing; processed:

sample a: retail weft pulling, surface hydrolysis, staining, sample b: surface hydrolysis, staining, sample c: weft pulling, staining, sample d: staining.

Small-scale extraction: in two stages between the comb rollers, in which the pressure on the goods was pneumatically kept constant: the goods had previously been treated with a non-ionic plasticizer; extraction in the wet state at room temperature. The draw was 65% elongation at break, the draw rate was 100% per second.

Hydrolysis: for 1 hour at 80 ° C maintaining the initial sample size, addition of polyglycol to dissolve 10 g per liter.

Dyeing: 3% by weight, dispersion blue 60 according to the Color Index

Prototype; dye · manufactured by ICI, Manchester, England, 2 ml / 1 75% acetic acid and 5 g / 1 o-phenylphenol as carrier.

Aac samples being withdrawn in small areas which considerably deeper dyeing than similarly processed, but not before being withdrawn samples ba · d. Malooblastní withdrawal induced increase strength at break of about ¹ 7%, and increase in width by 6%. The increment of strength remained the same if the heat was stabilized after extraction

Due to the fact that the processing was practically completely transferred to the warp threads after the small-scale processing, the goods appeared to have considerable flexibility in the warp direction.

Note: In the case of sheets of fiber with a high elastic elongation at break, the degree of elongation, in percent elongation at break, cannot be deduced from the mere extension of the dimensions in the extended direction. behaved virtually inflexible and was placed on the goods zone in the pulling direction and was pulled out with it.

Example 1 a d 2

Nylon 6.0 taffeta with 56/36 fibers per cm was treated as follows after washing:

sample a: retail drawing, disperse dye dyeing, sample b: free retail drawing, disperse dye staining, sample c: retail drawing, acid dye staining, sample d: non retail drawing, dyeing dye.

Small-scale weft pulling: between wet rollers, 65% elongation at break, pulling speed 50% per second, 10% width increment.

Dyeing: disperse dye, 2% disperse blue 60, according to Color Index Prototype 4% 30% sulfuric acid, after 1 hour boiling.

Coloring: acid dye, 4% acid red 85 Color Index Prototype of 4% 30% sulfuric acid for 1 hour at boiling.

In both cases the samples appeared before; pulled out in small areas, deeper staining than un pulled samples.

Example 3

Wool muslin was treated as follows in the weft direction;

20S403 sample a: anti-felting treatment, for example by chlorination, treatment with urea solution to reduce intermolecular bonds, retail extrusion, urea scrubbing, drying, sample b: as sample a but with little extrusion, sample c: as sample a but without chlorination with small extrusion ,

Sample Sample d: as Sample b, but without hinting and also without retail drawing.

Small-scale extrusion: between the rack rollers in the weft shift, while the depth of intersection of the rack rollers was mechanically maintained by a confrontational pulling rate of 40% per second.

.dimension change in weft strength change at [breakage direction against untreated fabrics a b c d +7% –4%

4-6% —2% +8% —6 o / o

4-6%

-0 o / o

Example 4

A mixed fabric of 33% cotton and 67% ethylene glycol terephthalate fibers, reinforced, with 30/25 threads per cm, was treated as follows after desizing and bleaching:

Sample a: Finishing with dye solution, Small-area drawing in the wet state, Drying while maintaining the dimensions obtained at a constant size, Sample b: Sample followed by heat setting at 210 ° C for up to 45 seconds.

Low-elastic pulling: in the weft direction between the comb rollers. The depth of penetration of the comb rollers was kept constant by mechanical means. Pulling speed 40% per second.

Sample to increase tear strength over unprocessed samples; and

Bc

d

Example 5 + 10% + 21%%

-1-2%

The stripped and bleached reinforced fabric of blended yarn, consisting of 50% cotton and 50% nylon 6, was weft in the wet state; in the direction of 100% per second and 60% elongation at break. Drying was then carried out while maintaining the dimensions obtained, followed by lye treatment, whereby the fabric was able to shrink freely in the weft direction. After washing, the drawing was again carried out in the small areas under the same conditions as before, drying, thermal stabilization and then finishing with 60 g / l dimethylethylene urea, 30 g / l polyethylene plasticizer and 6 g / l magnesium chloride hexahydrate, drying while holding the dimensions obtained, and heated to 150 ° C for about 3 minutes to reinforce the cotton.

Monitoring of operations: small-area drawing, shrinkage of the cotton component and small-area drawing in the weft yarn disposition in the sense that the cotton fibers were enriched inside the yarns and the polyamide fiber content was mainly enriched on the surface. By stabilizing this configuration by thermally fixing or crosslinking, it has become wash-resistant.

The tear strength of the fabric drawn in small areas was 15% higher than that of the fabric treated analogously, however. not subjected to retail extraction. The width of the second fabric was 8% smaller than the width of the first fabric.

Example 6

Cotton poplin with 36/18 threads was dried to 40 why, residual moisture and without chilling at 80 ° C, after wiping off, bleaching and dyeing, was subjected to weft pulling in the weft direction using a comb roller, pulling speed 200% per second and pulling $ 0% elongation at break. The ash weft was formed by a yarn, its twist corresponding almost entirely to the twist of the two threads, but had the opposite twist direction. The drawing in the small areas, in which the weft processing has virtually disappeared completely, while the warp-y processing has intensified, has therefore acted not only parallel to the yarn axis but also parallel to the fiber axis. Drying was then carried out. The tear strength of poplin due to pulling in small areas has increased by 25% in the weft direction.

Example 7

The same poplin as in the previous example was treated with a 30 ° Beaumé merceration concentration after merge-off and bleaching under longitudinal draw, and after a period of exposure of 60 seconds a three-stage extraction was performed in small areas using comb rolls. During the drawing-out, the working-up of the weft yarn completely disappeared, i.e. the drawing in the swollen state was carried out parallel to the yarn axis and also parallel to the fiber axis. Then it was done · · _r neutralization washing and rinsing.

The merchandise thus treated appeared to have at least as good a mercerizing shine as the mercerized mercerizing merchandise. The area obtained was 5% larger than for goods that had been otherwise treated the same way but were not pulled out of the small areas.

When the fabric was devoid of swelling and dried without substantially reducing the width obtained in the retail stretch, it exhibited high longitudinal elasticity. The escape showed no more processing. The tensile strength of the goods in the weft direction was 20% greater than that of the goods that were not processed in small areas, the area profit was 8%,

The articles were simultaneously processed for crosslinking with a sample, otherwise equally processed but not subjected to extrusion, using 120 g / l of dimethylolpropylene urea, 25 g / l of polyethylene plasticizer and 12 g / l of zinc nitrate. The fabric drawn in small areas appeared to recover 270 [deg.] C, the warp and weft sum of AATCC 66—1959, washing and abrasion effect values of 4 to 5, as determined by AATCC 88—1961, the specimen showed no strength loss at break, whereas the unstretched in small areas but the otherwise treated part of the goods showed a loss of 35% at the same recovery angle and the same washing and scraping effect, the unstretched and unmercered sample then 40%.

The sheave of the same poplin was subjected to nialo-elastic pulling in the weft direction with the help of comb rollers before mercerization, then mercerized as above. At the subsequent crosslinking, this clip also showed no loss of strength with otherwise the same properties as the other crosslinked samples.

Example 8

(a) The triacetate fabric with 42/30 threads per cm has been treated as follows after usual washing:

sample a: retail weft pulling, sample b: retail weft pulling, heat fixation, sample c: retail weft pulling, surface hydrolysis, dyeing sample d: no processing sample e: surface hydrolysis, dyeing

Small-scale drawing: between the rack rollers, the drawing speed is 100% per second, the drawing is 80% elongation at break.

Thermal stabilization: 45'7200 ° C

Surface hydrolysis: 300 g / l sodium hydroxide, treatment time 2 minutes at 60 ° C then rinsed.

Dyeing: 1% direct blue 80 at 95 ° C processed for 60 minutes, Grant 1: 35, addition of 2% sodium sulfate.

weft direction increment% 14%% 14%

Sample c was stained in the same bath with a much deeper color than the unstretched sample, but otherwise subjected to the same hydrolysis, i.e. the uptake of the direct dyes was considerably higher, hence a higher degree of saponification.

b) The same fabric was pulled in the warp direction using comb rolls. Here, the dye uptake was considerably higher after the surface saponification, when stained with the direct dye, in the pre-drawn sample.

Performing small-scale pulling in the warp direction:

The apparatus used consisted of two successive endless rubber bands, which were reinforced with a fabric and in which the rubber thickness was 2.5 cm. Shore hardness 60; these rubber bands were pressed against each other at the interface by rollers which were subjected to a pressure of 12 tons. The fabric running between the rubber bands was subjected to a strong elongation in the longitudinal direction at infinitely small elongated areas by the pressure exerted in the slit between the belts and thereby increasing the area of the rubber.

The surface hydrolysis and subsequent dyeing with the said direct dye gave the same results as in the weft stretching.

Due to the significant shift of the processing from the warp to the weft, the goods had great elasticity in the weft direction.

Example 1 9

The spun nylon 6 fabric with 38/36 threads per cm was subjected to washing and bleaching. It was then subjected to a low-stretch drawing between the heated comb rolls at a roller temperature of 190 ° C and a drawing rate of 20% per second; due to the plastic deformation at the contact points induced by the hot comb rollers, permanent mechanical deformation occurred simultaneously. The treatment was repeated several times so that the fabric then had a large number of fine grooves or ribs extending in the warp direction. In the following boiling dyeing, this phenomenon intensified as the hot cylinder contact points stabilized in their configuration, while the other fiber fractions were not stabilized and therefore appeared to shrink in the boiling liquid. Finally, the entire textile band was heat stabilized at 200 ° C for 15 seconds.

With considerable surface gain, the fabric appeared to have a mechanical deformation or texture that was washable.

Example 10

The nylon 6.6 nylon cretone, filament yarn, with 31/16 threads per cm, was after the washing of the treatment stage, which was immediately embrittled by the fiber surface, for example pretreatment of the aminoplast in the presence of ammonium sulfate under very vigorous conditions. Thereafter, the drawing was carried out in the direction of the warp by means of a small-area drawing, using a device such as; in Example 8b), whereupon a small-area stretching between the comb rolls in the weft direction was performed. Whereas, in the pretreatment, the surface wetting of the fibers greatly reduced the elongation at break in the fiber surface, at a value of 5 to 10 ·%, whereas the interior of the fibers had a value of 25% of the fibers, and the pull-out lay at 15 to 20%, the fiber surface shattering and tearing, resulting in greater roughening and structural arrangement in the fiber surface. · The friction from fiber to fiber has increased considerably and the material appeared to have changed considerably to the touch.

Example 11

After peeling, bleaching, mercerizing and dyeing, the cotton gabarden was subjected to a weft pull in the weft direction without prior drying in the following manner:

For the processing, comb rollers having relatively sharp edges and made of bronze were used in which grooves were milled, the edges of which were only slightly polished by grinding but not rounded. A cotton fabric that had been pre-coated with a 30 g / l acrylic grid-capable acrylic polymer solution, Primal HA 8, manufactured by Rohm &amp; Haas, Philadelphia, USA, and which had been pulled wet, received a 6 ° pull corresponds to 70% elongation at break. Thereafter, drying and heating to 130 degrees Celsius were carried out for 4 minutes to form the acrylic lattice. There was no reaction with the fiber. The fabric showed an increase in strength of 17% and had longitudinal strips that had the appearance of a woven effect. The effect was stable during the wash by avoidance, although the cotton fiber itself was not treated in any way to form a lattice. The same effect is obtained when the cotton fabric contained only water when stretched.

Example 12

Pure cotton poplin was subjected to two-stage pulling in small areas in the weft direction, each time between two pairs of comb rollers, after sizing, boiling, bleaching and wet dyeing. The draw was a total of · 65 ·% elongation of the fabric at rupture, with two-thirds of the pulling being performed between the first pair of comb rollers' and the last third in the second stage of pulling. The increase in tear strength in the weft direction was 18%. Thereafter, the fabric was processed in three variations, while maintaining the width achieved during low-speed pulling:

a) drying, then finishing with a grid forming agent, re-drying in the same. width and heating at 150 ° C for 4 minutes to · initiate the reaction between the pulp and the lattice forming agent and finally to wash;

b) merceration on a warp mercer, while essentially maintaining the width achieved in the small-scale drawing, after neutralizing the re-drying while maintaining a constant width and forming a lattice as in variation a); ~

c) processing as in variant a), but after application of the lattice forming agent, it is dried to 8% residual moisture while maintaining a constant width, followed by extrusion at the temperature of the engraved metal roll 2.00. ° C, then heated and washed as above;

d) an additional section of the same poplin was sized in the same bath without small drawing in order to form a lattice of variation a, c, dried, heated and washed exactly as described above.

Pull Variation Surface Recovery Angle Wash and Abrasion Loss as a result of gain after crushing the effect of the weft grating adjusting the tensile strength at tear to tear-off

and 8% 7.5% 270 ° 4 0% 45% profit b 8% 6% 265 ° 4 5% 40% profit C 8% 6.5% 5% 35% profit d - - 270 ° 4 35% 36% loss

Small-scale pulling out: control by pulling out pulling force, pulling speed 100% · per second, moisture content in goods when pulling 50%.

Grid formation: 80 g / l of dimethylolpropylene pulp, 15 g / l of zinc nitrate, 30 g / l of polyethylene plasticizer, squeezing effect: 65%.

Washing: 1 g / l of nonionic surfactant, held at 50 ° C for 20 minutes.

Determination of the crush recovery angle: AATCC 66 [1959 / T., Indicating both warp and weft sum.

Determination of washing and abrasion effect: AATCC 88/1961 / T.

In another variation of the example, the fabric was dried after dyeing, and then the above agent was applied to form a catalyst and plasticizer lattice, the squeezing effect being the same as the other variations, i.e. 65%. Without drying, the goods were then subjected to small-scale drawing under exactly the same conditions as the variation and, while maintaining the width obtained, and then, as mentioned, were heated and washed. The areal gain was 7.5-8%, the crease recovery angle was 265 °, the wash and abrasion effect was 4, the crosslinking loss by 2% and the tear strength gain was 30%.

Example 1 and d 13

The lawn-like cotton fabric was subjected to the following treatments after the usual pre-treatment, in particular sizing, bleaching, mercerizing:

(a) cross-linking without retail withdrawal;

(b) small-scale drawing in the warp direction, crosslinking;

c) small-scale pulling in the warp direction and then in the weft direction, crosslinking.

Cross-linking was carried out with 160 g / l dimethylolpropyleneurea using 50% commercial product, 50% 30% polyethylene softener, and 14 g / l zinc nitrate by filtration, drying at 90 degrees Celsius and condensing for 4 minutes at 150 [deg.] C.

The small-stretch drawing in the warp direction was accomplished by compression between two elastic bodies, namely by processing a wet fabric between two endless rubber bands which were pressed together strongly at one point between the rollers. Both rollers were powered and used again to power rubber belts. The compression of the two rubber bands resulted in an increase in the surface in the direction of the rubber bands, which in turn resulted in the pulling of the intermediate fabric in the warp direction on areas practically infinitely small.

The thickness of the rubber bands was 10 mm for one and 15 mm for the second, and the Shore hardness was 60 for the first and 55 for the second.

The results obtained in the following table were obtained.

and b C Tensile strength in kp warp 19.5 19.5 19.5 for unprocessed goods escape 24.0 24.0 24.0 Stretch in the warp direction - 6% 6% Pulling in the direction of the weft  - - 8% Tear strength in kp warp 13.0 19.5 17.5 after crosslinking escape 1.6,0 - 20.0 Loss of strength by crosslinking warp 33% 0% 10.5% escape 33% - 17%

Example 14

The reinforced cotton fabric was mercerized on a non-warp after scaling, boiling and bleaching. and then processed as in Example 1 to increase intermolecular binding by crosslinking until insolubility in Cuoixam was obtained.

The following variations were made to this procedure:

(a) retail weft pulling using comb rollers prior to merceration, thereby achieving an increase in tear strength in weft direction 33 why, and a tear strength increase in weft direction of 22%;

(b) small-scale drawing in the swollen lye state, during mercerisation, again in the weft direction using comb rollers;

(c) retail withdrawal before and during merceration;

(d) small-scale hauling, morcering;

(e) no retail withdrawal.

Retail Extraction: Extraction was controlled by limiting the penetration depth of the rollers, the rate of withdrawal was 50% per second.

Results:

Replacement Area profit after adjustment Pulling Loss of breaking strength at crosslinking Loss of tear strength after crosslinking and 4% 9% 15% 23% loss b 6% 8% 14% 25% loss C 7% 9 9% 19%, loss d 8,% 8% 7% 21% loss E - - 40% 62% loss

Example 1 5

The cotton cretone was subjected, after desizing, boiling and bleaching without intermediate, drying, to a small weft pull in the weft direction using comb rollers with a pull-out of 60% elongation at break and at a pull-out rate of 100 why, per second. The increase in tear strength in the weft direction was 9%. Thereafter, leaching of the merceration concentration was effected without tension in the weft direction, after which a 15% shrinkage occurred in the weft direction.

Results:

Replacement Break strength, weft Tear strength, weft Washing and abrasion effect Final width without news cování 17,5 kp 500 - 90 cm and 0,8 kp - 4 85 cm b 16,0 kp 550 4 101 cm C 7,0 kp - - 78 cm d 8,0 kp 250 3—4 90 cm

Both variations a] and c), which both were treated with caustic without stretching, appeared to exhibit elastic behavior in the weft direction. The elasticity of the variation (a) was 11%, of which 1% was an irreversible elongation, whereas the variation c] also exhibited elasticity of 11%, while irreversible each with one comparative piece that was not subjected to retail extrusion.

a] drying, then crosslinking, as in Example 1,

b] repeating the weft pulling, drying and crosslinking while keeping the width obtained during pulling,

(c) same as point (a) but without low-level hauling,

(d) the same as * (b), but without low-level hauling, either before or after processing.

The share was 3%. Thus, the variation that was subjected to low-stretch drawing prior to caustic treatment appeared to have considerably less area loss, better strength, and less irreversible elongation.

Example 16

A fabric made up of a blended yarn consisting of 50% cotton and 50% polynose regenerated cellulose fibers, after washing, was subjected to pulling in small areas in the weft direction in two steps between two pairs of comb rollers, the pulling rate controlled by adjusting the penetration depth . Near and at the edges of the fabric, the fabric was held by rubber belts running in the recesses of the comb rollers. Between the extraction stages and thereafter, the fabric was flatly stretched by spiral expansion.

The fabric contained 55% water when pulled. After drying, the tear strength in the weft direction increased by 5% (o), the Elmendorf tear strength by 8%, after the cross-linking treatment with dimethylol-dioxyethyleneurea, while drying to the pull-out dimensions of the pre-drawn fabric was obtained in the weft strength direction of 16 kp as well as in the weft strength direction of the Elmendorf tear strength 600, while the same fabric with the same reinforcement treatment but without prior extraction yielded 9 kp and 350 respectively. both fabrics the same. The drawn fabric showed a width greater by 10 cm.

Claims (23)

> SCOPE OF THE INVENTION A method of improving the physical properties of fibers, yarns or yarns processed into textile fabrics by stretching these articles in small areas by deflecting the fabrics from its plane while retaining its dimensions, the elongation forces acting at each time only within a narrow a strip perpendicular to the textile zone in the form of numerous small areas, the elongation forces act only in the elongated direction, the elongation force causes at least 10% elongation of this material at elongation in the elongated direction, the intermolecular cohesion of the fiber material decreases the stretching is again brought back at least to. Initial condition, characterized in that the fibers, yarns or yarns of synthetic polymers and / or wool or cellulose are stretched at a rate of at least 10 proc./sec in small areas, and this stretching is combined with the preceding or subsequent processing of the fibers , yarns or yarns to stabilize their configuration. 2. A method according to claim 1, wherein the textile sheet is subjected to at least a temporary withdrawal of the drawn fiber assembly in at least one stage in small areas, wherein: at each time point, the drawing forces act only within the strip transversely to the longitudinal direction of the textile and mainly only in the direction of the drawn system of fibers. 3. A method according to claim 1, wherein the textile sheet consists of fibers of natural or regenerated pulp, pulp derivatives, such as pulp esters, protein fibers, polyamides, acrylic or woolen polymers, copolymers or blends. polymers, polyesters, polyurethanes, polycarbonates, polyureas, or mixtures of different types of fibers, are subjected to said drawing in small areas at temperatures between -10 ° C and +250 ° C, wherein the drawing-out is carried out in at least one stage, and the material at the time of drawing comprises at least 30% water, optionally colored or color-forming pigments, as well as agents which cause an additional increase in the intermolecular bond of the fibrous material or the agent which affects the friction between the fibers and the yarns or hand. 4. A method according to claim 1, wherein, when deflecting the sheet from its plane, the dimensions of the sheet regions are kept the same and the pulling out is at a drawing stage of at least 30% elongation of the sheet when broken in the pulling direction; in which the intermolecular bond of its fibrous material has been released upon extraction, is pulled into a smooth shape before increasing the intermolecular bond at least to its original state by bringing the regions deflected from its plane back into the plane of the sheet. 5. The method of claim 4, wherein the sheet is held at any time in a strip extending transversely to its longitudinal direction and holding the distance between the two edges of the material zone and deflecting portions of the material zone to either side of the plane. The waveform and the amplitude of the waveform are varied to induce pull in small areas of a predetermined size. 6. A method according to claim 5, characterized in that the configuration of the fibers or yarns or fiber components or yarns obtained during the extraction is stabilized by restoring the intermocular bond of the fibrous material to at least its original state so that formation of covalent or non-covalent bonds between the chains of macromolecules deposited or assisted in situ generated reagents capable of increasing the degree of binding between the macromolecules, or by a physical treatment such as heat treatment or treatment with ^1. Beams which increase the intermolecular binding or cohesion of the fibrous material. 7. Method according to claim 1, characterized in that the sheet is treated with a swelling agent before being pulled out or shrinked before being pulled out. 8. A method according to claim 1, characterized in that the sheet is treated with swelling agents after drawing by drawing, optionally allowing it to contract in at least one direction. 9. The method of claim 1, wherein the at least one withdrawal stage comprises a strong swelling agent, and after the withdrawal is complete, the original state of interboundary cohesion of the fibrous material is restored. to the original value, possibly increased by introducing new bridges between the chains of macromolecules. 10. Method according to claim 1, characterized in that after the drawing-out, the configuration of the fibers, threads or yarns is stabilized against washing by thermal fixation, possibly also by crosslinking. 11. A method according to claim 3, characterized in that the sheet is subjected to extraction prior to processing to make the fiber, yarn or yarn configuration stable to the wash. 12. A method according to claim 3, characterized by: characterized in that the pull-out treatment is repeated after the processing is carried out. •. Apparatus for carrying out the method according to claim 1, characterized by at least one pair of interlocking groove or comb rollers (20, 22; 30, 32), at least one of which is driven and by means which act in the gap between the rollers (20). 22, 30, 32). and / or adjacent thereto, and which prevents stranding of the sheet (10) in the pulling direction in the region of the comb rollers, wherein the devices acting in the gap between the rollers (20, 22; 30, 32) consist of rings (44) of elastic material drawn between the ridges formed by the ribs (36, 38) in the end section of the rollers. 14. The apparatus of claim 13, wherein at least. behind each pair of comb or groove rollers [20, 22; 30, 32), an expander device (14, 28, 34) is provided. The apparatus of claim 13, wherein each pair of groove rollers (20, 22) is disposed between two spreader devices (14, 28). Apparatus according to claim 15, characterized in that the expander device (14) comprises a driven roller, on the housing of which there are oppositely directed helical formations (16, 18). Apparatus according to claim 13, characterized in that the rings (44) have the shape of a hose and are filled with a pressurized environment. Apparatus according to claim 13, characterized in that the rings (44) are resilient in the region of the gap between the rollers (20, 22). deformable by the ridges (38) of the second cylinder engaging the grooves of the rings comprising the. 19. The apparatus of claim 13, wherein the width of the gap between. cylinder is adjustable. Apparatus according to claim 13, characterized in that the rings (44) are inserted into the grooves (40, 42) of one of the grooved rollers (20, 22) of each pair of rollers. Apparatus according to Claim 13, characterized in that a friction-reducing layer is provided between the rings and between their abutment surfaces in the grooves (40, 42), which, when the rings (44) deform, allow their length to be compensated within the groove (40, 42). 42). Apparatus according to Claim 13, characterized in that the rings are inserted into the grooves (40) of the driven roller (20). Device according to Claim 13, characterized in that it comprises at least two successive pairs of grooved rollers (20, 22; 30, 32), between which a spacing device (28) is arranged.