EP0598195A1 - Method and apparatus for treating a yarn-like product - Google Patents

Abstract

What is described is a method for treating a thread-like structure, especially a sewing yarn or other yarn, a slubbing or a roving, in which the thread-like structure is transported at a predetermined speed relative to a treatment appliance in order to vary its properties. The treatment appliance is designed in such a way that, during treatment, the thread-like structure is subjected to a spark discharge and/or to a brief arc discharge. An apparatus for carrying out the method has a treatment appliance which comprises a transport system for the thread-like structure as well as at least one electrode, located at a distance from at least one counterelectrode, for generating the spark discharge and/or the brief arc discharge, the at least one electrode and the at least one counterelectrode being connected to a voltage source. <IMAGE>

Description

The present invention relates to a method for treating a thread-like structure with the features of the preamble of claim 1, a device for carrying out the method with the features of the preamble of claim 21 and the use of a correspondingly treated thread-like structure.

In order to change the properties of thread-like structures, such as, for example, sewing threads or other threads, slivers, rovings, card slivers, thread-like or ribbon-like nonwoven layers, it is known to provide the thread-like structures mentioned above with appropriate equipment. Such equipment is applied in such a way that the thread-like structure, provided that it is stable in the longitudinal direction against stress, is passed through an appropriate solution or dispersion of equipment, so that a defined part of the solution or dispersion contained equipment remains on the thread-like structure. However, if the thread-like structure is not stable in the longitudinal direction in relation to the application of tension, the aforementioned solution or dispersion of the equipment is sprayed onto the thread-like structure.

However, such known methods have the disadvantage that there is always the problem that only part of the equipment remains on the thread-like structure, while another part of the solution or dispersion contained in the equipment gets into the waste water. In addition, the desired changes in properties which can be achieved in the known method are limited.

The present invention has for its object to provide a method of the type specified, in which the possibility of changing the properties of the thread-like structure to be treated is multiplied.

According to the invention, this object is achieved by a method having the characterizing features of patent claim 1.

The method according to the invention for treating a thread-like structure, in particular for treating a sewing thread, another thread, a sliver or a roving, provides that the thread-like structure is transported relative to a treatment device at a predetermined speed in order to change its properties. Here, the treatment in the method according to the invention is contactless carried out, wherein the treatment device is designed such that the thread-like structure is temporarily or continuously subjected to a spark and / or short-term arc discharge during the transport of the structure through the treatment device. In other words, the method according to the invention thus suggests a contactless spark and / or short-term arc discharge of the thread-like structure in order to specifically and reproducibly change the properties of the thread-like structure (for example sewing thread, other thread, sliver, roving).

The method according to the invention has a number of advantages. Due to the fact that the treatment according to the invention is preferably carried out without contact, there can be no uncontrolled influencing of properties, which is always the case in the prior art when the thread-like structure is subjected to mechanical stress during the treatment. In the method according to the invention, changes in properties of the thread-like structure can also be brought about by the spark and / or short-term arc discharges without it being necessary to apply appropriate equipment to the thread-like structure. Depending on the respective energy of the spark and / or short-term arc discharges, it is possible, for example, to roughen the surface of the thread-like structure, to remove it or to fuse it at certain points or areas, so that a corresponding physical modification of the material from which the thread-like structure is made occurs. Furthermore it could be determined that the contact-free treatment of the thread-like structure with a spark and / or short-term arc discharge due to the presence of air during the treatment brings about chemical changes in the material from which the thread-like structure is made, which can be caused, for example, by the method according to the invention express that a thread-like material treated in this way has a considerably improved adhesion to other surfaces, such as finishing agents, preparations, adhesives, equipment, paints, binders or the like. Furthermore, the method according to the invention can be modified particularly simply to the effect that a thread-like structure treated hereafter has changed properties with regard to hydrophilicity, hydrophobicity, oleophilicity or oleophobia, without it being necessary to apply appropriate finishing products to the surface of the thread-like structure . Furthermore, in the method according to the invention, by selecting suitable products, these products can be chemically and / or physically bound to the material from which the thread-like structure is made, so that it is almost impossible or impossible to later remove these products from the surface without destroying them to remove the thread-like structure. The mere fact that design variants of the method according to the invention enable changes in the properties of the thread-like structure without it being necessary to apply appropriate finishing agents to the thread-like material, the method according to the invention contributes significantly to reducing the environmental impact, since no equipment products get into the exhaust air or wastewater.

The advantages of the method according to the invention described above are particularly evident when a sewing thread is treated as a thread-like structure by the method according to the invention. It was found here that due to the fact that in the method according to the invention there is no contact treatment and thus no mechanical fluctuations in tension occur, there are no changes in the treatment of sewing threads that negatively affect the mechanical-technological properties, such as the maximum tensile strength or tensile strength influence. This is attributed to the fact that in the method according to the invention there is no pre-damage to the sewing thread and thus also no capillary breaks or tears, so that the sewing thread treated according to the invention because of the aforementioned missing capillary damage or the missing capillary breaks during subsequent processing or Use in confection can be used with great success. Furthermore, depending on the particular energy of the spark or short-term arc discharge, the outer capillaries of the sewing thread can be welded to other outer capillaries and / or internal capillaries at certain points, short distances or as seen over the entire axial length, with these welding areas be formed in that the fiber material is melted by the spark or arc discharge and then solidifies again. This in turn means that the Thread closure of a sewing thread treated in this way is considerably improved, so that a sewing thread treated according to the invention has particularly good sewing behavior. This improved sewing behavior of the sewing thread treated according to the invention is expressed in comparison to an identical sewing thread, which, however, does not have the melting ranges mentioned above, in the fact that the sewing thread treated according to the method according to the invention has the frequency of thread breakage, for example in multidirectional sewing at high processing speeds (up to 7,000 stitches / minute) or when sewing buttonholes is significantly reduced. Furthermore, it was found that the contactless treatment of the sewing thread with a spark and / or short-term arc discharge due to the presence of air during the treatment alone brings about chemical and / or physical changes in the fiber polymer forming the sewing thread, simply as claimed in the method according to the invention, which are expressed, for example, in the fact that a sewing thread treated in this way has a substantially better adhesion between the surface of the sewing thread and equipment attached to it. Furthermore, the method according to the invention can be modified in such a way that a sewing thread treated according to it has an increased hydrophilicity and a reduced oleophilia without it being necessary to apply appropriate finishing products to the surface of the synthetic sewing thread. These improvements are attributed to the fact that the fiber polymer forming the sewing thread is physically and / or in particular chemically modified by the treatment according to the invention. Consequently The method according to the invention can also be used to bring about changes in properties, in particular in the case of appropriately treated sewing threads, which can at best only be achieved by conventional methods in that appropriate finishing products are applied to the surface of the treated sewing thread. This in turn leads to the fact that the method according to the invention is also particularly suitable for sewing threads with regard to its environmental compatibility, as has already been generally stated above for the thread-like structure.

Depending on the desired axial extent of the effects brought about by the spark and / or short-term arc discharge, the thread-like structure and in particular also the sewing thread is temporarily or continuously subjected to the spark and / or short-term arc discharge during transport. If the changes brought about by the method according to the invention are to extend over the entire axial length of the thread-like structure, then constant treatment during the transport of the thread-like structure through the treatment device with the spark and / or brief arc discharge is necessary, while for a partial and in Seen in the axial direction of the thread-like structure, an interrupted change in the method according to the invention is achieved in that the thread-like structure is only temporarily subjected to spark and / or short-term arc discharge during transport.

A first embodiment of the method according to the invention provides that the method according to the invention is carried out in a gas atmosphere, for example in a protective gas atmosphere, an air atmosphere and / or an atmosphere of reactive gases. Here, the gas pressure varies in the range of the normal pressure range, preferably between 90 x 10³ Pa to 110 x 10³ Pa, in particular at a pressure in the range of about 10⁵ Pa.

Regarding the treatment temperature, i.e. the temperature of the thread-like structure during the treatment, it can be determined in the process according to the invention that this treatment temperature normally varies between 15 ° C. and 200 ° C., preferably between 20 ° C. and 60 ° C. Due to these relatively low temperatures, no undesirable physical structure changes occur in the process according to the invention, so that the process according to the invention accordingly does not cause any undesirable changes, for example in the original shrinkage behavior of the thread-like structure and in particular in the sewing threads, for example in the boiling shrinkage behavior or the hot air shrinkage behavior.

As already described above, the method according to the invention can be carried out in a gas atmosphere. Inert gases, such as one noble gas or several noble gases, nitrogen or a mixture of the aforementioned gases, air and / or reactive gases or gas mixtures are used for this. The selection of the gas used or of the gas mixture used depends on the material from which the thread-like structure is made and the changes in properties that are desired. If, for example, the individual threads of a multi-thread thread-like structure, in particular a sewing thread, are seen to be fused together over the axial length, point or area, without a chemical change in the material from which the thread-like structure or sewing thread consists, it is advisable to use a protective gas atmosphere (noble gases, nitrogen). In the simplest case, this protective gas atmosphere can be achieved in the method according to the invention by flushing the thread-like structure or sewing thread with the appropriate protective gas during the spark and / or brief arc discharge.

It is also possible to use the spark and / or short-term arc discharge to split up the fiber polymers forming the thread-like structure and thereby create reactive polymer-own centers that interact with one another and / or with other substances, for example the aforementioned reactive gases, with the formation of modified fiber polymers react.

If, on the other hand, the method according to the invention is to bring about a chemical change in the material from which the thread-like structure is made, one works with spark and / or short-term arc discharge in an air atmosphere or in an atmosphere of reactive gases. To achieve Such a chemical change is then preferably used as reactive gases oxygen, hydrogen, ammonia, carbon monoxide, carbon dioxide, sulfur dioxide, sulfur trioxide, either alone or in a mixture, with the result that functional groups form on the surface of the thread-like structure and in particular the sewing thread which then cause, for example, a change in the dyeing behavior, the chemical bonding of equipment, preparations, finishing agents, the hydrophobization or hydrophilization, the oleophobization or oleophilization or the antistatic behavior of such a thread-like structure or sewing thread provided with functional groups.

Instead of the gases described above or in addition to the gases described above, another embodiment of the method according to the invention provides that before and / or during the treatment of the thread-like structure (sewing thread, other threads, slubber, roving, card, fleece layer) with the spark and / or brief arc discharge the thread-like structure is impregnated with at least one substance. Depending on the substance used in each case, the conditions of the spark and / or short-term arc discharge, the dwell time and the treatment temperature, it can occur that the substance in question chemically and / or physically on the surface of the thread-like structure and / or inside the thread-like structure is bound or that reactive substances are formed from the respective substance by the spark and / or short-term arc discharge, which then either directly with the material that the thread-like structure forms, react or initially react with one another, for example polymerize and / or oligomerize, so that the components reacted with one another are then chemically and / or physically fixed on and / or in the thread-like structure. In this way, such thread-like structures can be produced in a particularly simple manner that are chemically modified or that are provided with corresponding substance layers on the surface.

The selection of the substance described in the previously described embodiment of the method according to the invention depends on the desired change in properties of the thread-like structure. If, for example, the substance of a textile fuse or a textile roving is to improve the thread closure of the roving or the fibers or threads forming the fuse, it is advisable to select a substance here which is influenced by the spark and / or or short-term arc discharge melts, so that the melted substance bonds the individual fibers or threads to one another during later solidification. The same applies if a yarn is spun from multifilaments or a large number of individual fiber yarns or if a thread is made from at least two rovings. If, on the other hand, it is desired to roughen the surface of the thread-like structure, this can be achieved in the process according to the invention by grafting on or grafting on monomers, oligomers or polymers limited in places or on partial areas, which on the one hand increases the surface roughness and on the other hand that Adhesion to other substrates is improved. Concrete comes for the previously exemplified substance polymerizable or oligomerizable monomers, for example acrylates, acrylic acid derivatives, vinyl acetates, vinyl alcohol derivatives or the like. in question.

Another embodiment variant of the method according to the invention provides that the method according to the invention serves to improve the thread closure of yarns and in particular of sewing threads. This is achieved in that polymerisable and / or oligomerisable substances are applied to the substrate to be treated before or during the spark and / or brief arc discharge, and in particular are incorporated into the interstices of fibers or threads of the fibers or threads forming the yarn, so that these substances then polymerize or oligomerize through the spark or short-term arc discharge and thus cause the fibers or threads to stick together. In particular, in this embodiment variant of the method according to the invention, the thread to be treated in each case and in particular the sewing thread to be treated in each case are subjected to a constant spark and / or brief arc discharge while the thread is being transported through the treatment device. In particular, in this embodiment of the method according to the invention, the polymerizable or oligomerizable monomers mentioned in the previous section are used as the substance.

If, on the other hand, it is desired to improve the sliding behavior of the thread-like structure and in particular a sewing thread by using the method according to the invention, then For this purpose, preferably oligomerizable or polymerizable organic silicon compounds are selected, which are then physically and / or preferably chemically fixed on the surface of the thread-like structure by the spark and / or brief arc discharge. This in turn leads to the fact that the aforementioned substances, which change the thread closure or the roughness of the surfaces, or those substances which improve the sliding behavior of the thread-like structure, due to their fixation to the material from which the thread-like structure is made, during further processing or do not rub off when using the thread-like structure, so that corresponding disturbances in the processing of the thread-like structure are avoided.

Likewise, by using the method according to the invention, it is possible to chemically and / or physically fix those substances on the surface of the thread-like structure that completely cover the thread-like structure so that, for example, the burning behavior is improved or the surface abrasion of the thread-like structure is reduced.

In the context of the present application, the term thread-like structure is to be understood to mean all such materials which predominantly have a large axial extent with a small width, that is to say, for example, all threads, fiber yarns, multifilament fibers, yarns, slivers, card slivers, rovings, tapes, non-woven layers or the like. In particular, this includes yarns (fiber yarns, multifilament yarns) or threads made of polyamide6, polyamide6.6, polyester, (Polyethylene terephthalate) glass, polyalkylene and / or carbon fibers.

In another embodiment of the method according to the invention, during and / or before the treatment of the thread-like structure, the thread-like structure is impregnated with at least one initiator, which breaks down into radicals and / or ions as a result of the treatment (spark and / or brief arc discharge). Reactive particles (radicals and / or ions) thus arise directly on the surface of the thread-like structure, which can then optionally be combined with the material from which the thread-like structure is made, the gaseous ambient atmosphere of the thread-like structure and / or a substance applied to the thread-like structure react. This embodiment variant enables a particularly simple and inexpensive physical and in particular also chemical modification of the thread-like structure, the substances mentioned above and / or the gases described above being used in this variant.

In principle, any initiator that is modified by the spark and / or short-term arc discharge in such a way that it breaks down into radicals and / or ions can be used in the embodiment of the method according to the invention described above. Initiators based on a persulfate, in particular potassium persulfate and / or ammonium persulfate, a peroxide, in particular dibenzoyl peroxide, cumene hydroperoxide, cyclohexanone peroxide, ditert-butyl peroxide, cyclohexylsulfonylacetyl peroxide, initiators are preferably available for this purpose based on an azo compound, in particular azodiisobutyronitrile, and / or an initiator based on benzpinacol, diisopropyl percarbonate and / or tert-butyl peroctoate.

Furthermore, it was found that a redox system, in particular potassium persulfate / sodium hyposulfite, hydrogen peroxide / iron (II) sulfate, cumene hydroperoxide / polyamine and / or benzoyl peroxide / N-dimethylaniline, can also be used as initiator in the process according to the invention, since these can be used successfully beforehand mentioned redox systems form the reactive centers described above in a particularly high yield.

In a development of the method according to the invention, the thread-like structure to be treated in each case is swollen before and / or during the application of the initiator by applying a swelling agent. This variant allows the reactive centers, which are formed from the initiator by the spark and / or short-term arc discharge, to be located exclusively or partially in the interior of the thread-like structure due to the previous swelling thereof, so that, accordingly, the reactions described above are also exclusively or partially run inside the thread of the thread-like structure.

Another embodiment of the method according to the invention provides that the at least one initiator is applied to the thread-like structure together with the at least one substance becomes. This variant of the method according to the invention is always used when an oligomerizable and / or polymerizable substance is to react with the reactive centers formed by the decomposition of the initiator.

As already mentioned above, the substances applied to the thread-like structure can be arranged inside the thread-like structure, on its surface or both inside and on its surface. In order to change, for example, the hydrophilicity or hydrophobicity, the oleophobicity or the oleopholy, the sliding behavior, the adhesiveness or the electrostatic charge of the thread-like structure processed by the method according to the invention, it is advisable to use the above-mentioned substances in one layer or preferably to be arranged in several layers on the surface of the thread-like structure. To build up the various layers one above the other, it is advisable to first impregnate the thread-like structure with the first layer, then subject the thread-like structure to a spark and / or short-term arc discharge, then re-impregnate with a second substance and then to subject the thread-like structure impregnated in this way to a second spark and / or short-term arc discharge, the structure of the subsequent layers first providing a corresponding impregnation and then providing a spark and / or short-term arc discharge.

With regard to the alignment of the spark and / or short-term arc discharge relative to the direction of transport of the thread-like structure, it should be noted that there are basically two possibilities in the method according to the invention. Thus, the first possibility provides that the spark and / or arc discharge is oriented in the transport direction or opposite to the transport direction of the thread-like structure, while in the second possibility the spark and / or brief arc discharge is at an angle between 75 ° and 105 °, in particular at an angle of about 90 °, relative to the direction of transport of the thread-like structure. If, on the other hand, a particularly high energy exposure of the thread-like structure by the spark and / or arc discharge is desired, it is particularly advisable to use the two options described above simultaneously, i.e. align the spark and / or short-term arc discharge both at the aforementioned angles transversely to the transport direction of the thread-like structure and in the transport direction and / or in the opposite direction, as is described below in an exemplary embodiment of the method according to the invention.

In order to reproducibly generate the spark and / or short-term arc discharge required for this in the method according to the invention, it is advisable to apply an AC voltage or a high-frequency voltage. Such a voltage supply is always recommended when a large number of spark and / or arc discharges are present in the method according to the invention are generated, in which case a single voltage source is preferably used.

In order to ensure particularly high-energy spark discharges or short-term arc discharges in the method according to the invention, a further development provides that a voltage source with a voltage below 50 kV, in particular with a voltage between 2 kV and 25 kV, is used here.

Regarding the time required to achieve the previously described changes in the thread-like structure and in particular the sewing thread, it should generally be noted that this treatment time depends on the desired changes in properties, the material used for the thread-like structure and the required energy of the spark. and / or arc discharge directed. In the method according to the invention, the treatment time is usually less than 2 seconds and preferably varies between 0.01 seconds and 1.5 seconds.

Regarding the transport speed with which the thread-like structure is transported relative to the treatment device in the method according to the invention, it should be noted that this transport speed is generally between 20 m / min and 1,500 m / min, preferably between 150 m / min and 800 m / min , fluctuates.

The present invention further relates to an apparatus for performing the method according to the invention described above.

The device according to the invention for carrying out the method described above has a treatment device which comprises a transport system for the thread-like structure and at least one electrode arranged at a distance from at least one counterelectrode for generating the spark and / or brief arc discharge. Here, the at least one electrode and the at least one counter electrode are connected to a voltage source. Due to the fact that, in the simplest case, the device according to the invention comprises only two electrodes (counterelectrode and electrode) and a voltage source in addition to the transport system for the continuous transport of the thread-like structure, the device according to the invention has a particularly small construction. This in turn has the consequence that the device according to the invention can in principle be used anywhere in the processing sequence of the manufacture or processing of the thread-like structure. The device according to the invention can also be produced very cheaply because of the relatively few components.

Regarding the design of the transport system for the thread-like structure, it should be noted that there are various options here. In the simplest case, the transport system is formed by two deflection rollers arranged at a distance from one another, these two deflection rollers optionally being driven or not being driven. It is the same possible to drive only one of the two deflecting rollers, it then being advisable to drive the second deflecting roller as seen in the transport direction, it then being appropriate to wrap this deflecting roller at least once with the thread-like structure to be transported, so that such a looped deflecting roller as Trigger mechanism serves and thus ensures the required constancy of the speed of transport of the thread-like structure. The electrodes and the counterelectrode are then positioned between these deflection rollers which are arranged at a distance from one another.

In an advantageous further development of the previously described embodiment, in which the transport system is formed from two rollers arranged at a distance from one another, one roller is connected as an electrode and the other as a counter electrode. This then leads to the spark or short-term arc discharge being formed in the transport direction of the thread-like structure or in the opposite direction to the transport direction of the thread-like structure. The same orientation of the spark and / or short-term arc discharge can also be achieved in that at least one ring electrode and one ring-shaped counter electrode are positioned between the two rollers, the transported thread-like structure then being guided through the ring interior of the ring-shaped electrode.

If the spark or short-term arc discharge is to be formed transversely at the angles previously given in the process for the transport direction of the thread-like structure, the at least one electrode and the associated at least one counter electrode are positioned laterally at a distance from the transported thread-like structure, as will be explained in more detail below in a further exemplary embodiment.

Another possibility of designing the transport system for the thread-like structure provides that here the transport system comprises a laying device and a winding device for a spool of the thread-like structure. The thread-like structure is thus subjected to the spark and / or brief arc discharge while it is being wound on the winding device. The laying device causes the thread-like structure to be wound evenly distributed over the axial length of the coil. This embodiment variant of the device according to the invention has the advantage that, compared to the embodiment described above, the thread-like structure can be subjected to the discharge of sparks or arcs for a considerably longer time at the same processing speed.

In a particularly suitable development of the embodiment described above, the winding device is then connected as an electrode or counterelectrode. In this case, the winding device is preferably switched as an electrode, while the counter electrode is arranged at a distance from the winding device and in particular extends over the entire axial length of the winding device, so that the counter electrode arranged at a distance from the winding device ensures a uniform spark or arc discharge across the entire axial width of the correspondingly wound coil.

The previously described embodiment of the device according to the invention is to be used in particular where the thread-like structure can be provided with a certain amount of mechanical tension during transport, in particular with sewing threads or other threads. If this is not the case, which can apply, for example, to card slivers or rovings, it is advisable to design the transport system in such a way that the thread-like structure lies against the transport system and is transported when the transport system moves. To achieve this, the transport system can be designed, for example, as a transport roller with a correspondingly large diameter.

A particularly suitable embodiment of the device according to the invention provides that the transport system is designed as an endless conveyor belt so that the thread-like structure is placed on the endless conveyor belt for transport.

In a particularly advantageous development of the previously described embodiment variant of the device according to the invention, in which the transport system is designed as a conveyor belt, the conveyor belt is made of an electrically conductive material, for example copper, aluminum, iron or steel. Above the conveyor belt on which the thread-like If the structure is deposited for transport, the at least one counter electrode is positioned, while the electrically conductive conveyor belt is connected as an electrode. This ensures that the thread-like structure is subjected to the spark and / or short-term arc discharge while it is being transported by means of the conveyor belt. Of course, however, it is also possible to arrange the at least one electrode above the conveyor belt, so that in this case the conveyor belt itself is then switched as a counter electrode. In order to prevent an undesirable spark and / or short-term arc discharge, which would occur laterally next to the thread-like structure and which would then not be directed at the thread-like structure, in this development of the device according to the invention, the side areas of the electrically conductive conveyor belt are made from an insulator to manufacture, so that the thread-like structure rests on the electrically conductive conveyor belt and is held laterally by the insulator.

In order to ensure a spark and / or arc discharge which is constant in terms of energy and / or occurs at all electrodes in the device according to the invention and thus to ensure reproducible effects, a further, particularly advantageous embodiment of the device according to the invention provides that each counter electrode has at least one capacitor is assigned, which is connected between the respective counter electrode and the voltage source. Such an embodiment of the device according to the invention is particularly useful when a row of electrodes and a row of counter electrodes are provided, wherein the row of counter electrodes or the row of electrodes extend along the transport path of the thread-like structure. Here, the capacitors assigned to the counter electrodes cause the electrodes to be electrically decoupled. Instead of the capacitors, however, resistors can also be provided, whereby however current losses occur due to the heating of the resistors, which are avoided when using capacitors. By varying the capacitance of the capacitor, it is also possible to limit the power of the spark and / or short-term arc discharge and to keep it at a predetermined value. Furthermore, this embodiment variant of the device according to the invention prevents the spark or arc discharge taking place only on one electrode or on a few electrodes, so that the discharges extend uniformly over all electrodes. In addition, with such an arrangement, an unlimited number of counter electrodes and electrodes can be operated via a single voltage source.

A particularly suitable development of the previously described embodiment of the device according to the invention, in which at least one capacitor is assigned to each counterelectrode, provides that the capacitor is designed as a coaxial cable. This development has the advantage that by varying the length of the coaxial cable, the capacitance of the capacitor designed as a coaxial cable can be varied in a particularly simple manner, so that the spark and / or short-term power can be achieved in any way and within a very short time Arc discharge can be changed and adapted to the respective conditions.

Regarding the capacitance of the capacitor, which is connected between the at least one counter electrode and the voltage source, it should be noted that this varies between 5 pF and 5,000 pF, preferably between 100 pF and 1,500 pF.

In the embodiments of the device according to the invention, in which several electrodes and a corresponding number of counter electrodes are connected to a single voltage source, it should be noted that the respective electrodes and the respective counter electrodes are preferably connected in parallel.

With regard to the materials from which the electrode and the counterelectrode are made, it should generally be stated that electrically conductive materials, in particular those materials which do not change their properties under the respective conditions of spark or short-term arc discharge, are selected for this. For example, the electrode or the counter electrode can be made from metals or metal alloys, in particular from aluminum, copper, iron, stainless steel, platinum, platinum alloys, tungsten or nickel, aluminum, iron or copper being preferred for reasons of cost. It is also possible to select an electrically conductive liquid or an electrically conductive melt as the electrode or counter electrode.

Another, particularly suitable embodiment of the device according to the invention provides that each counter electrode is assigned a second capacitor, the second capacitor preferably connecting the counter electrode to the associated electrode. Here, this second capacitor allows the time course of the spark or short-term arc discharge and thus the frequency range of the discharge to be modulated in time.

The capacitance of this second capacitor depends on the desired modulation, preferably capacitors are used as second capacitors whose capacitance is equal to or less than the capacitance of the first capacitor. In particular, those second capacitors are used whose capacitance is 10% to 90% of the capacitance of the first capacitor.

The previously described variation of the capacitance of the second capacitor and thus the modulation of the spark and / or short-term arc discharge can be achieved in a particularly simple manner in that the second capacitor is also designed as a coaxial cable, with a change in the length of the coaxial cable the desired capacitance of such a second capacitor can be set.

The device according to the invention preferably has a treatment device which has a plurality of counter electrodes, in particular two, which are arranged at a distance from one another to forty counter electrodes. These counter electrodes are connected in parallel and connected to a single common voltage source, a number of electrodes corresponding to the number of counter electrodes also being connected to this common voltage source. With such a treatment device, it is possible in a particularly simple manner to change the intensity of the treatment, ie the number of spark and arc discharges acting on the thread-like structure, by varying the number of counter electrodes and the electrodes belonging to them.

Regarding the voltage source to which the at least one electrode and the at least one counter electrode are connected in the device according to the invention, it should be noted that a voltage source designed as an AC voltage is preferably used. Usually this voltage source then generates an AC voltage with a frequency between 5 Hz and 20,000 Hz, preferably 50 Hz.

With regard to the voltage generated by the voltage source provided in the device according to the invention, it should be noted that the magnitude of this voltage depends on the configuration and arrangement of the at least one counter electrode and the electrode associated therewith. The device according to the invention usually has a voltage source which generates an alternating voltage between 500 V and 50 kV, preferably between 2 kV and 25 kV.

In order to apply the substances mentioned above in the method according to the invention to the thread-like structure, there is the possibility of applying appropriate solutions or dispersions of the substances or applying them by means of a padder. However, this possibility is only given in the case of thread-like structures which can be subjected to mechanical stressing for transport, in particular in the case of sewing threads or other threads. If this is not possible with special thread-like structures, it is advisable to spray or mist the corresponding dispersion or solution of the substances here, and it has proven to be particularly advantageous if the tension-sensitive thread-like structure is used by a suitable transport system, for example is supported and transported at the same time by a transport roller with a correspondingly large diameter or by a conveyor belt.

The thread-like structure treated by the method according to the invention is preferably used to produce reinforcing layers for composite materials such as tires, tarpaulin, carbon fiber reinforced plastics, polyester reinforced plastics or the like. It has been shown here that such composites have a long service life because, due to the physical and / or chemical change in the surface of the thread-like structure, there is a high level of adhesion between the thread-like structure and the surrounding composite material, for example rubber or plastic.

As has already been emphasized several times above, the method according to the invention and the device according to the invention are preferably used for sewing threads. In the context of this application, the term sewing thread includes threads made from synthetic fibers, in particular polyamide6, polyamide6.6 and / or polyester fibers (polyethylene terephthalate fibers), from natural fibers, in particular from cotton and / or silk fibers, or from mixtures of synthetic fibers and natural fibers of the type mentioned above. Particularly good results can be achieved by the method according to the invention and with the device according to the invention with sewing threads which consist of 100% polyester fibers (polyethylene terephthalate fibers). With regard to the construction of such sewing threads, it should be noted that this includes both fiber threads, filament threads or filament fiber threads in the usual sewing thread construction, in particular twisted threads, core threads and / or air-entangled threads, the titer of such threads being between 100 dtex and 3,500 dtex, preferably vary between 500 dtex and 1,500 dtex.

For example, it was found that the sliding behavior of sewing threads is considerably improved by using the method according to the invention if an oligomerizable or polymerizable organic silicon compound, optionally together with the aforementioned initiators, is applied as substance to the sewing thread, the silicon compound then physically and / or preferably chemically to the spark or short-term arc discharge the fiber polymer forming the sewing thread is fixed. This in turn leads to the fact that such connections, which improve the sliding behavior of the sewing thread and, depending on their chemical structure, also the thread closure of the sewing thread, do not rub off due to their fixation on the fiber polymer during further processing or use of the sewing thread, so that corresponding disturbances in the Processing can be avoided. Furthermore, substances fixed in this way, provided that they are predominantly arranged in the surface area of the sewing thread, can improve the sewing behavior in such a way that substances fixed in this way, with the formation of a layer enveloping the sewing thread, improve the thermal resistance of the sewing thread and / or the sliding behavior of the sewing thread during processing in one Modify the desired way so that sewing threads treated in this way have a considerably improved sewing ability.

Furthermore, by using the method according to the invention, it is possible to apply to the sewing thread a substance which alters, preferably reduces, the water absorption capacity of the sewing thread. For this purpose, preference is given to using substances which are based on fluorocarboxylic acid compounds, organosilicon compounds or on the basis of mixtures of fluorocarboxylic acid compounds with organosilicon compounds.

As already mentioned above, the substances described above can be inside the sewing thread, on its surface and both inside and on the sewing thread surface to be ordered. In order to change, for example, the hydrophilicity or hydrophobicity, the oliophobia or oliophilicity, the sliding behavior or the electrostatic charging of the sewing thread processed by the method according to the invention, it makes sense to provide the substances mentioned above on the surface. If, on the other hand, the thread closure of the sewing thread is to be improved, it is advisable to arrange the substances used for this purpose inside the sewing thread so that the fibers and / or filaments forming the sewing thread are glued from the inside.

Above and below, the term is used repeatedly for a short time in connection with the spark and / or arc discharge. This is to be understood to mean that the discharge takes place between 10 Zeit¹ seconds and 10⁻⁸ seconds, preferably 10⁻⁶ seconds and 10⁻² seconds.

Advantageous developments of the method according to the invention and the device according to the invention are specified in the subclaims.

Figur 1

ein allgemeines Schaltbild;

Figur 2

eine Abwandlung des in Figur 1 wiedergegebenen Schaltbildes;

Figur 3

eine schematische Seitenansicht einer ersten Ausführungsform der Vorrichtung;

Figur 4

eine schematische Ansicht einer zweiten Ausführungsform der Vorrichtung;

Figur 5

eine schematische Ansicht einer dritten Ausführungsform der Vorrichtung;

Figur 6

eine schematische Darstellung einer vierten Ausführungsform der Vorrichtung;

Figur 7

eine schematische Darstellung einer fünften Ausführungsform der Vorrichtung; und

Figur 7a

ein Schnitt längs der Linie A-B in Figur 7.

The device according to the invention is explained in more detail below using five embodiments in conjunction with the drawing. Show it:

Figure 1

a general circuit diagram;

Figure 2

a modification of that shown in Figure 1 Circuit diagram;

Figure 3

a schematic side view of a first embodiment of the device;

Figure 4

a schematic view of a second embodiment of the device;

Figure 5

a schematic view of a third embodiment of the device;

Figure 6

a schematic representation of a fourth embodiment of the device;

Figure 7

a schematic representation of a fifth embodiment of the device; and

Figure 7a

a section along the line AB in Figure 7.

In Figures 1 to 7, the same parts are provided with the same reference numerals.

FIG. 1 schematically depicts a circuit diagram which is used in the embodiments of the device shown in FIGS. 3 to 6. Here, the circuit has a voltage source 1, the voltage source 1 generating, for example, an alternating voltage of 5 kV with a frequency of 50 Hz. With this voltage source 1 three electrodes 2, 3 and 4 shown by way of example and three examples shown are shown Counter electrodes 5, 6 and 7 connected, both the electrodes 2 to 4 and the counter electrodes 5 to 7 being connected in parallel. Each counter electrode 5 to 7 is assigned a capacitor 8, 9 or 10, the capacitors 8 to 10 having a capacitance of 500 pF. In other words, the counter electrodes 5 to 7 are thus decoupled, which leads to the fact that when a voltage is applied between the electrodes 5 and 2, the electrodes 6 and 3 and the electrodes 7 and 4 when a certain limit voltage is exceeded, caused by the electrode spacing and by the capacitance of the capacitors 8 to 10 is determined, an electrical spark and / or short-term arc discharge is formed.

The circuit diagram shown in FIG. 2 differs from the circuit diagram described above in that the circuit here has a second capacitor 11. Here, too, the circuit comprises a voltage source 1, a first capacitor 8, a counter electrode 5, an electrode 2, only one pair of electrodes 5 and 2 being shown in FIG. 2 by way of example. A second capacitor 11 is connected in parallel with the electrodes 5 and 2 and effects a temporal modulation of the spark or short-term arc discharge taking place between the electrodes 5 and 2. The capacitor 11 has a capacitance of 400 pF. The voltage source 1 generates such a voltage as was specified above for the circuit diagram 1.

FIG. 3 shows a first embodiment of the device, the device being a transport system for the thread-like structure 21. The transport system for the thread-like structure 21 comprises a take-off mechanism 22, a lower deflection roller 23, a deflection pin 24 and a deflection pin 25. The thread-like structure 21 is transported in the direction of the arrow 27 by rotating the extraction device 22 in front of the roller 23 a total of 20 product application device provided. In this case, the product application device 20 comprises a chassis 28 for receiving a liquid product and a planting roller 29 which extends partially into the chassis and is rotatably supported by the chassis. The planting roller 29 is in contact with the thread-like structure 21.

Seen in the direction of transport of the thread-like structure 21, the deflection roller 23 is followed by a cylindrical tubular body 30 which is provided with a cylindrical bore 31 through which the thread-like structure 21 is guided. Four electrodes 2, 3, 4 and 4a shown by way of example and four counter electrodes 5, 6, 7 and 7a shown by way of example are arranged within the cylindrical body, which consists of an electrically insulating material, these electrodes (2-4, 4a 5 - 7, 7a) are designed as ring electrodes. Each counter electrode 5 - 7, 7a is assigned a capacitor 8, 9, 10 and 10a. The electrodes and counterelectrodes are each connected to the AC voltage source denoted by 1, the voltage source generating a voltage of 10 kV at a frequency of 50 Hz.

A gas inlet valve 32 and a gas outlet valve 33 are arranged at the foot and top of the cylindrical body 30, with which it is possible to introduce a gas into the region of the bore 31.

The embodiment shown above in FIG. 3 works as follows:
First, a product is applied to the application device 20 by means of the platen roller 29 onto the thread-like structure 21 transported along the application device 20. The correspondingly impregnated thread-like structure 21 is then transported in the direction of arrow 27 and then reaches the region of the bore 31, where a spark or short-term arc discharge is carried out. This discharge forms between the electrode pairs 10a and 4a, 7 and 4, 6 and 3 and 5 and 2 in the transport direction 27 of the yarn. This in turn leads to the fact that the substance applied at 20 is crosslinked or chemically and / or physically bound to the thread-like structure, so that the appropriately equipped structure can be drawn off via the take-off device 22 or wound up accordingly.

With the embodiment of the device shown in FIG. 3, a thread-like structure was made hydrophobic. A mixture of an aqueous emulsion of a fluorocarbon resin with a silicone oil was used, this emulsion having 20 parts by weight of fluorocarbon resin and 80 parts by weight of silicone oil. The product order was 4% by weight. The transport speed was 300 m / min. The voltage applied to the voltage source 1 was 10 kV, which means that a spark discharge of normally 1 cm in length was formed between the electrodes (2-4, 4a; 5-7, 7a).

In parallel, the same thread-like structure was equipped with the same hydrophobicizing agent described above. To condense the hydrophobizing agent, the thread-like structure was subjected to hot air treatment at 180 ° for 75 minutes. The thread-like structure thus conventionally equipped, like the thread-like structure equipped on the device described above, was sewn individually onto a corresponding waterproof fabric. The two seams were then tested for watertightness, and it was found that the seam made with the conventionally equipped thread-like structure became wet after 120 minutes, while the seam made with the thread-like structure which was equipped on the device shown in FIG. 3 itself after 240 Minutes not soaked.

Even after 4 washes at 60 °, there was no change in the water permeability described above.

The second embodiment shown in FIG. 4 differs from the previously described embodiment in that the thread-like structure is wound on a winding device 40 in the form of a bobbin. The winding device 40 has a winding core 2, which is electrical is conductive and connected to the voltage source 1 so that the core 2 forms the electrode. A series of counter electrodes 5, 6, 7 and 7a is arranged above the winding device 40 and at a distance from the core 2, these counter electrodes being connected to the voltage source 1 via corresponding capacitors 8, 9, 10 and 10a. The winding device 40 is also assigned a laying device, not shown, which ensures that the thread-like structure 21 is distributed uniformly over the axial extension of the core 2. Due to the fact that the thread-like structure is itself electrically conductive by appropriate impregnation with an electrically conductive solution of a substance, a forms between the counter electrodes 5 to 7 and 7a and the electrode 2 (core) via the electrically conductive and wound thread-like structure 21 Spark and / or brief arc discharge, which has the consequence that the substance applied to the thread-like structure is condensed or crosslinked.

The embodiment of the device shown schematically in FIG. 5 has a transport system for the thread-like structure 21, which consists of a take-off device 22 and a delivery device 23. Here, the two devices 22 and 23 are designed as corresponding rollers around which the thread-like structure 21 is deflected and transported in the direction of the arrow 27 accordingly.

The delivery device 23 is connected as a counter electrode and a capacitor 8 with the AC voltage source U₂ connected. The trigger device 22 is designed as an electrode and connected directly to the voltage source U₂.

A counter electrode 5 and an electrode 2 are arranged at an angle of 90 ° relative to the transport direction of the thread-like structure, these two electrodes being positioned at a distance from one another. The counter electrode 5 is connected via a capacitor 9 to the voltage source U 1 and the electrode 2 directly to the AC voltage source U 1.

If the thread-like structure 21 is now impregnated with an aqueous solution, dispersion or suspension of a conductive substance in front of the delivery device 23, as is described, for example, in FIG. 3, and then reaches the area between the two devices 23 and 22, Thus, due to the conductivity of the wet thread-like structure 21, it is first heated, which leads to drying of the thread-like structure. As soon as the thread-like structure has dried, this point being designated by A in FIG. 5, an electrical spark and / or short-term arc discharge is formed in the transport direction 27 of the thread-like structure, as is indicated by F₂ in FIG. 5. Here, the distance between the delivery device 23 and the trigger device 22 is selected such that a direct spark breakdown between the devices 22 and 23 is prevented. Furthermore, a second spark and / or arc discharge is formed between the electrodes 5 and 2, this second discharge takes place transversely to the direction of transport of the thread-like structure and is indicated by F₁ in the drawing. Both the discharge F₁ and F₂ lead to the previously described fixation of the equipment on the thread-like structure. Furthermore, the discharge F₂ causes the thread-like structure, depending on the transport speed, to be dried at least to the extent that it can be wound up without problems.

The embodiment of the device shown in FIG. 6, like the previously described embodiment, has a take-off device 22 and a delivery device 23, the take-off device 22 and the delivery device 23 being designed as rollers. This ensures that the thread-like structure 21 is transported in the direction of arrow 27 at a predetermined continuous speed. The extraction device 22 and the delivery device 23 are connected in parallel and connected to the voltage source 1, the voltage source generating an alternating voltage. Three counter electrodes 5 to 7 shown by way of example are likewise connected to the voltage source 1 via three capacitors 8 to 10, the counter electrodes 5, 6 and 7 also being connected in parallel.

If the thread-like structure 21 is now impregnated with an electrically conductive substance, which leads to the thread-like structure also becoming conductive, and if the thread-like structure thus impregnated and conductive reaches the area between the devices 23 and 22, corresponding lines are formed here Spark and / or short-term arc discharges from F₁ to F₃. As a result, the substance is chemically and / or physically fixed to the thread-like structure, as has already been described several times above. At the same time, the discharges change the electrical conductivity of the thread-like structure, so that the formation of the spark and / or short-term arc discharge is automatically interrupted when the minimum conductivity value of the thread-like structure falls below. As a result, the corresponding treatment process can be controlled in a particularly simple manner.

The embodiment of the device shown in FIGS. 7 and 7a serves in particular for those thread-like structures 50 which must not be subjected to mechanical tension during the spark and / or brief arc discharge for the purpose of transport. The device has a support roller 41 and a conveyor belt 42, the support roller 41 being driven in the direction of arrow 43, while the conveyor belt 42 is moved in the direction of arrow 44. The result of this movement is that the thread-like structure 50 is transported in the direction 27 with a corresponding rotation of the roller 41 and a corresponding movement of the conveyor belt 42. At the end of the conveyor belt 42, a winding roller 45 is arranged, whereupon the thread-like structure 50 is wound up.

Above the roller 41, an impregnation nozzle 46 is arranged, through which a solution or dispersion of a substance on the thread-like structures 50 is dusted. In order not to prevent the thread-like structure from being stressed, the thread-like structure lies on the surface of the transport roller 41 during dusting.

A series of counter electrodes are arranged above the conveyor belt 42, the counter electrodes 5 to 7 being shown here only by way of example. The counter electrodes extend in the transport direction of the thread-like structure. In addition to the corresponding capacitors 8, 9 and 10, the counter electrodes 5 to 7 connected in parallel are connected to a voltage source 1. Furthermore, the conveyor belt 42, which consists of an electrically conductive material, is connected as an electrode to the voltage source 1. This causes a spark and / or short-term arc discharge is formed, as shown by F₁ for example.

In order to ensure that the thread-like structure, which, as can best be seen in FIG. 7a, consists of a large number of individual threads, is properly treated with the spark and / or brief arc discharge F 1, the conveyor belt 42 has a central region 51 (Figure 7a), which consists of the electrically conductive material. Two insulator sections 52 and 53 are provided laterally on the central region 51 of the conveyor belt 50, so that the spark and / or brief arc discharge is always directed onto the central region 51 of the conveyor belt.

There is also the possibility of designing the previously described conveyor belt 50 as a conveyor roller, the diameter of the conveyor roller being chosen to be correspondingly large. Here, the transport roller has a central, electrically conductive area which is in contact with the thread-like structure and supports the thread-like structure. This middle area is delimited by a side area in each case, the side areas projecting radially beyond the middle area and being made of an electrically insulating material, as described above for the insulator sections 52 and 53 of the conveyor belt 50.

The embodiments of the device shown in FIGS. 3-6 can also be used excellently for the treatment of yarns, in particular sewing threads.

Claims (43)

Method for treating a thread-like structure, in particular a sewing thread or another thread, a sliver or a roving, in which the thread-like structure is transported relative to a treatment device at a predetermined speed in order to change its properties, characterized in that the treatment device is designed in this way that the thread-like structure is temporarily or continuously subjected to a spark and / or brief arc discharge during the treatment. A method according to claim 1, characterized in that the treatment is carried out in a gas atmosphere at a pressure between 90 x 10³ Pa to 110 x 10³ Pa, preferably at a pressure of about 10⁵ Pa. A method according to claim 1 or 2, characterized in that the treatment at a temperature between 15 ° C and 200 ° C, preferably at a temperature between 20 ° C and 60 ° C, is carried out. Method according to one of the preceding claims, characterized in that the treatment is carried out in an atmosphere of reactive gases. Method according to one of the preceding claims, characterized in that the thread-like structure is impregnated with at least one substance before and / or during the treatment. Method according to one of the preceding claims, characterized in that before and / or during the treatment, the thread-like structure is impregnated with at least one initiator, which breaks down into radicals and / or ions as a result of the spark and / or brief arc discharge. Process according to Claim 6, characterized in that an initiator based on a persulfate, in particular potassium persulfate and / or ammonium persulfate, a peroxide, in particular dibenzoyl peroxide, cumene hydroperoxide, cyclohexanone peroxide, di-tert-butyl peroxide, cyclohexylsulfonylacetyl peroxide, an azo compound, in particular azoidiisobutyl or an initiator based on benzpinacol, diisopropyl percarbonate and / or tert-butyl peroctoate is selected. Process according to Claim 6 or 7, characterized in that a redox system, in particular potassium persulfate / sodium hyposulfite, hydrogen peroxide / iron (II) sulfate, cumene hydroperoxide / polyamine and / or benzoyl peroxide / N-dimethylaniline, is used as the initiator. Method according to one of the preceding claims, characterized in that the thread-like structure is swollen before and / or during the application of the initiator by applying a swelling agent. Method according to one of claims 5 to 9, characterized in that the at least one initiator is applied to the thread-like structure together with the at least one substance. Method according to claims 5 or 10, characterized in that such a substance is selected for the impregnation of the thread-like structure that improves the thread closure and / or the adhesiveness of the thread-like structure. Method according to one of the preceding claims, characterized in that a thread, in particular a sewing thread made of polyamide6, polyamide6.6, polyester, glass, polyalkylene and / or carbon fibers is selected as the thread-like structure. Method according to one of claims 5, 10, 11 or 12, characterized in that several substances in layers are superimposed on the thread-like structure. Method according to one of the preceding claims, characterized in that the spark and / or short-term arc discharge is carried out in the transport direction of the thread-like structure or opposite to the transport direction of the thread-like structure. Method according to one of the preceding claims, characterized in that the spark and / or brief arc discharge takes place at an angle between 75 ° and 105 °, in particular at an angle of about 90 °, relative to the direction of transport of the thread-like structure. Method according to one of the preceding claims, characterized in that the thread-like structure is continuously subjected to spark and / or short-term arc discharge. Method according to one of the preceding claims, characterized in that an AC voltage or a high-frequency voltage is applied to generate the spark and / or the short-term arc discharge. Method according to one of the preceding claims, characterized in that a single voltage source is used to generate a plurality of spark and / or short-term arc discharges. Method according to one of the preceding claims, characterized in that a voltage source with a voltage less than 50 kV, in particular with a voltage between 2 kV and 25 kV, is used. Method according to one of the preceding claims, characterized in that the thread-like structure is subjected to the spark and / or brief arc discharge for a period of less than 2 seconds, preferably between 0.01 seconds and 1.5 seconds. Device for carrying out the method according to one of the preceding claims, characterized in that the device has a treatment device which has a transport system (22, 23, 40, 42) for the thread-like structure (21, 15) and at least one at a distance of at least one Counter electrode (5, 6, 7, 7a) arranged electrode (2, 3, 4, 4a) for generating the spark and / or short-term arc discharge, the at least one electrode (2, 3, 4, 4a) and the at least a counter electrode (5, 6, 7, 7a) are connected to a voltage source (1). Apparatus according to claim 21, characterized in that the transport system is formed from two rollers (22, 23) arranged at a distance from one another. Apparatus according to claim 22, characterized in that at least one of the two rollers (22, 23) is connected as an electrode or counter electrode. Apparatus according to claim 21, characterized in that the transport system comprises a laying device and a winding device (2, 40) for a bobbin of the thread-like structure. Apparatus according to claim 24, characterized in that the winding device (2, 40) is connected as an electrode or as a counter electrode. Apparatus according to claim 25, characterized in that the winding device (40) is connected as an electrode (2) and that the counter electrode (5, 6, 7) is arranged at a distance from the electrode (3) and extends over the entire axial length of the Winding device (40) extends. Apparatus according to claim 21, characterized in that the transport system comprises a conveyor belt (42) for the thread-like structure (50). Apparatus according to claim 27, characterized in that the conveyor belt (42) is made of an electrically conductive material which is arranged above the conveyor belt (42) and at a distance from the at least one counter electrode (5-7) and that the conveyor belt ( 42) is connected as an electrode. Device according to one of claims 21 to 28, characterized in that each counter electrode (5, 6, 7, 7a) at least a capacitor (8, 9, 10, 10a) is assigned, which is connected between the respective counter electrode (5, 6, 7, 7a) and the voltage source (1). Apparatus according to claim 29, characterized in that the capacitor (8, 9, 10, 10a) is designed as a coaxial cable. Apparatus according to claim 29 or 30, characterized in that the capacitance of the capacitor (8, 9, 10, 10a) is 5 pF to 5,000 pF, preferably 100 pF to 1,500 pF. Device according to one of the preceding claims 29 to 31, characterized in that the electrodes (2, 3, 4, 4a) and the counter electrodes (5, 6, 7, 7a) consist of a metal, in particular aluminum, copper or iron. Device according to one of claims 21 to 32, characterized in that a second capacitor (11) is assigned to each counter electrode (5, 6, 7, 7a). Apparatus according to claim 32, characterized in that the second capacitor (11) connects the counter electrode (5) to the electrode (2). Apparatus according to claim 33 or 34, characterized in that the second capacitor (11) has a capacitance which is equal to or less than the capacitance of the first capacitor. Apparatus according to claim 35, characterized in that the second capacitor has a capacitance which is 10% to 90% of the capacitance of the first capacitor. Device according to one of claims 21 to 36, characterized in that the treatment device has a plurality of counter electrodes (5, 6, 7, 7a) arranged at a distance from one another, in particular two to 40 counter electrodes (5, 6, 7, 7a), wherein the counter electrodes (5, 6, 7, 7a) are connected in parallel and connected to the common voltage source (1). Device according to one of claims 21 to 37, characterized in that the counter electrodes (5, 6, 7, 7a) are connected to a voltage source (1) designed as an AC voltage. Device according to one of claims 21 to 38, characterized in that the voltage source (1) generates an AC voltage with a frequency between 5 Hz and 20,000 Hz, preferably 50 Hz. Device according to one of claims 21 to 39, characterized in that the voltage source (1) generates an alternating voltage between 500 V and 50 kV, preferably between 2 kV and 25 kV. Use of the thread-like structure treated according to one of claims 1 to 20 for the production of reinforcement layers for composite materials. Use of the method described in claims 1 to 20 for the treatment of sewing threads. Use of the device for treating sewing threads as described in claims 21 to 40.

Images