DE1966031A1 - Continuous non-woven fabric - Google Patents

Abstract

Continuous non-woven fabric Polymer is extruded through spinnerets and gathered together in a strand of 50 - 150 threads. The bundle is subjected to jets of gas or air at supersonic speeds which disperse the fibre material onto a perforated carrier band for bonding so that a continuous non-woven fabric is produced from continuous-spun synthetic fibre.

Description

New documents Novel continuous thread fleece The invention relates to on a continuous thread fleece and a process su its productionG ira special the invention relates to the production of continuous thread nonwovens from synthetic Polymers such as B. polyolefins, polyamides, polyesters and / or their copolymers, which are processed into textile, felt or paper-like film material.

Well known and widely used are staple fiber webs. The production of fleece from continuously spun threads offers the advantage a simpler and faster production method in which the spinning and nonwoven manufacturing process with a more or less direct conversion in terms of undesirable non-uniformity Appearance and can be combined into threads that are immediately deposited as fleece can. The production of such nonwovens has, however, the previous technology again and again to the extent that it causes difficulties as the threads during spinning and laying had a tendency to maintain their spinning parallelism and sticking together like a wedge To form structures i.e. the non-woven fabric with an undesirable non-uniformity Appearance and strength given. In order to produce nonwovens, it is also necessary to form lengthwise adjacent individual webs, and the strength and The uniformity of these individual tracks depends essentially on neighboring or overlapping ones Share off.

In U.S. Patents 3,338,992 and 3,341,394 it has been suggested the above-mentioned disadvantages of gathering the threads into rope-like structures thereby avoiding that on the threads to be deposited an electrostatic one Landing is developed which repels them from one another, so that every single thread goes into the fleece in a confused manner, avoiding parallel bundles. here an attempt is made to achieve greater uniformity through a completely confused distribution and to avoid parallelism of the individual threads. According to the described Method m, the electrostatically charged thread must be stored so that the repelling like charges spread out in a fan shape and from each other Keep your distance, which limits the production speed and also difficulties when filing. However, such nonwovens do not achieve the strength of fleeces with parallel fiber bundles.

In a previously known process, the threads after spinning at maximum speed through an air nozzle sent to them peel off, stretch and as a tangled fleece onto something in motion To take off the tape. To produce a fleece in a practically usable width 'it was known, a number of adjacent individual webs from a number of air nozzles to drop out. It has generally been found desirable to place these air nozzles in sequence to be offset over the entire width of the storage conveyor belt so that a desired Overlap of the individual tracks was achieved. As a result, however, something happened that one could be referred to as a stratification between the individual sheets, d. H. those of the The individual lanes deposited in each subsequent air nozzles no longer had the den individual individual tracks have a peculiar strength. That was the case, for example, when the fleeces were laid down from a row of air nozzles that diagonally across the width of the storage and conveyor belt were arranged.

The object of the present invention is therefore to create a method which avoids the previous technical disadvantages and the production of a continuous thread fleece the end synthetic polymer at much higher production speeds allowed and achieved uniformity of the fleece properties and the Retains the parallel thread bundles serving for higher strength.

Another object of the present invention is to provide a new kind of fleece, which is opposed to by greater strength and uniformity every fleece received so far is marked.

In the following, embodiments of the invention are related described in more detail with the drawings.

They show: Fig. 1 a schematic cross-sectional representation of the nonwoven production according to the present invention-; Fig. 2 is a flow diagram of the step-by-step process and the essential parts of the device in a practical embodiment of the invention for the production of heat-sealed fleece; Fig. 3 is a cross-sectional view of a Pull-off and air nozzle for pulling off, drawing and laying down the threads; Fig. 4 a Detailed scheme of the way of depositing a thread bundle on a storage surface; Figure 5 is a cross-sectional view of the staggered arrangement of the air nozzles over the Shelf space; Fig. 5A shows the location of the stationary air nozzles; Fig. 53 oscillating air nozzles; Fig. 5C the setting of the air nozzles to achieve multiple overlap; Fig. 6 a schematic representation of the fine structure of a single web, which is from a Bundle of threads from a single air nozzle formed on the shelf has been; Fig.t a schematic representation of the fine structure of sub-bundles, into which the thread bundle is divided, and their loop-shaped arrangement and Fig. Figure 8 is a reproduction of a photomicrograph of one made in accordance with the invention Nonwoven web.

According to the present invention, a nonwoven web is produced by the simultaneous Spinning a multitude of filaments made from synthetic polymer. The spinning takes place in the usual way from the melt, with znn example the melt of the polymer from a plurality of downwardly directed and preferably is extruded in one or more rows of arranged spinnerets.

During the spinning, the threads become a straight line side by side and at an even distance from each other running, non-rotated Bundles with at least 15, but preferably 50 to 150 threads combined. Each this bundle is made simultaneously and at a rate of at least 3,000 m / min, preferably 3,500 to 8,000 m / min, in running at supersonic speed Gas radiate downwards and directed so that they are on a substantial Open the horizontal shelf. The gathering of the threads into bundles, their withdrawal and their impact on the haul-off belt is preferably carried out by the Sends bundles through air nozzles in which the threads are enveloped with an air jet, which closes down at supersonic speed. The air nozzles are in a more straight line Row above the shelf and at right angles to its direction of movement, so that the bundles enclosed in the gas jet are in motion when they strike The deposit belt located in a line or row at right angles above the deposit extend. The shelf can be a conventional shelf, such as that used in non-woven technology Is used, -z. 3. an endless belt as main belt. or the upper one Part of a drum as a sieve drum. The one made up of a number of threads running in parallel existing thread bundles are placed on the shelf in a loop-shaped arrangement, with the primary loops stretching the full width of a single sheet like them is defined by the impact of the air jet from a single air nozzle, trek back and forth. Before and when the parallel thread bundles are opened on the shelf they are split up into sub-bundles, which are only a smaller number have parallel threads and secondary, i.e. smaller loops and loops form that not only cross each other, but also the neighboring individual tracks lobes and thus essentially complete mixing with the overlapping ones Achieve parts of the neighboring individual tracks. Form the deposited thread bundles then a uniform continuous thread fleece, which is then compressed, heat-sealed, Needling or treating with a binder such as. B. latex or other in the non-woven technology known treatment methods are solidified and stabilized can.

The present invention contains mainly four process steps, namely: The spinning of the polymer thread, the drawing off and drawing as well as that Filing into a nonwoven web and its consolidation.

The threads commonly used in the present invention are oriented, crystalline, or crystallizable fibers made from any thermoplastic Polymer that enables a spinnable melt. Such polymers are the polyolefins, e.g. B. linear polyethylene, isotactic polypropylene, polyisobutylene, Polybutadiene and the like; Polyurethanes, polyvinyls and the like; Polyamides such as B. polyhexamethylene adipic acid amide and polycaproamide; Polyester such as 3. Polyethylene terephthalate and copolyester of ethylene glycol in a mixture with terephthalic and isoterephthalic traces or copolymers as well as Eondensationæmischpolymers, Block graft polymers and the like. on the basis of the same monomers as the above-mentioned polymers.

The polymer is melted, for example, in an extruder and the melt is pumped into the spinning device. The threads are spun with a spinning device producing a thread at a speed of at least Can produce 0.1 to 15 g per nozzle per minute. Appropriate equipment comprises a number of downwardly directed spinnerets containing molten polymer extrude and form the desired threads.

The spinnerets are expediently parallel in one or more rows to be arranged to the air nozzle bank, which is across the moving shelf extend. Optionally, each multi-hole spinneret produces at least one sufficient Number of threads for a trigger and air nozzle, d. H. at least 15 and preferably 50 to 150 filaments, although it is more common for a single spinneret to have a plurality supplied by air nozzles. For example, spinnerets with 200 to 1,000 outlet openings can be used be used. The spinneret orifices have a diameter of 0.1 to 1.5 mm, preferably from 0.3 to 1.2 mm to produce typical thread sizes.

The throughput of liquid polymer is generally from 0.5 to 1.5 g / min per outlet opening. The spinning temperature is usually 250 to 3500 C, which depends on the polymer that is extruded. The extruded Threads are cooled with cooling air.

The threads produced in the spinning machine are preferably on a thickness of approx. 10 to 50 microns, i.e. in the textile forming area, stretched. the Threads, for example, can be between about 1 and 20 deniers, though Lower or higher denier threads depending on although lower or higher denier threads higher denier can be used depending on the desired end product. So would man for the formation of a fleece for the production of a textile-like film material Filaments with a denier of 1 to 10, for the production of a paper-like sheet material However, use 3 to 12 denier threads. For thicker products like z. B. Carpet underlayment, thicker threads with a denier of 5 to 20 are used. The drawn threads generally have a break or breakage. Elongation at break over 80% and tensile strength or tensile strength over 2.5 g / den, d. H. from 3 to 7 g / den.

The threads spun in this way become a straight line next to each other Bundles with at least 15 threads each, but preferably 50 to 100 threads combined, stretched and blown out with an appropriate device.

These are preferably air nozzles, the air jets with the according to FIG The present invention are able to produce the required over-sounding speed. The threads emerging from the multi-hole spinnerets are bundled by a expedient arrangement of the air nozzles themselves or other expedient means.

The threads are run at high speeds of at least 3,000 deducted up to 8,000 m / min. The air nozzles that can be used for this purpose are expansion or suction nozzles.

Such an air nozzle has a nozzle part through its neck primarily Compressed air uniformly at supersonic speed into an outwardly diverging one Expansion chamber is expanded. A guide tube for threads and secondary suction air extends centrally through the throat and the expansion chamber up to a flue pipe with constant diameter. The primary compressed air flows essentially in parallel to the threads emerging from the guide tube without hitting them, d. H. without that a mixing and twisting of the threads takes place. Rather, it flows like this that a good spacing is maintained and preferably an expansion of the bundle and a division into sub-bundles with threads running in parallel is made possible. This becomes an essentially complete parallelism between reached the threads within the thread bundle emerging from the draw-off tube. In An appropriate configuration of an air nozzle is shown in Figure 3. In this the air nozzle consists of an upper part 2 which is screwed into a lower part 1 is.

The upper part 2 houses the conical hopper 3 for the Threads and the secondary air that opens into the guide tube 4. This conical inlet opening 3 has an opening angle of 5 ° to 15 °, preferably 7 ° to 11 °, in order to be kept apart of the threads as they pass through the nozzle. The height of the inlet funnel 3 must not be larger than 40 times the inner diameter of the guide tube part 4 be. Usually it is no larger than 10 to 20 times the inner diameter of the Tube 4. The lower part 1 of the air nozzle device has two ring-shaped bores Air inlets for the supply of primary compressed air and an annular distribution chamber 12. This distribution chamber is bounded on the inside by vertical inner walls 13, the up to end in a rounded edge 14, which is with the funnel-shaped nozzle cavity 15 is connected, which tapers inward to up to the narrowest point 16 in the neck.

The cavity then enlarges outwards towards the expansion chamber 17 and ends in a cylindrical exhaust pipe 18.

The conical enlargement of the nozzle cavity 15 to the outside is with Measured angle ß. This angle is generally from 8 to 200, preferably however 10 to 150. In this way, the outer wall of the guide tube 4 also forms the expansion chamber at point 16 has an annular neck through which the Compressed air accelerated to the speed of sound and down to the expansion chamber 17 is forwarded. The opening angle y of the shower funnel 15 is 20 to 500.

The annular surface between the end of the guide tube 4 and the beginning of the exhaust pipe 18 (i.e. the end of the expansion chamber 17) forms the annular cross-section of the expansion chamber. The end of the guide roll is pinned something below the beginning of the exhaust pipe 18, which is from above is uniformly cylindrical down to the bottom.

Another air jet device can be used in the present invention use provided it pulls threads at high speed while doing a mutual Able to eliminate the influence of the threads. For such air jet devices generally uses print media that expand to supersonic speeds and Mach numbers up to 3, T and more with a flow either parallel to the thread direction and reach slightly off the thread direction.

In this way, the pressurized gas will strike at an angle the filaments generally through a convenient construction of the expansion chamber in relation to the guide tube from which the threads emerge, avoided. The print medium is preferably cold or warm air, but steam or other media can also be used Find use. In general, the inlet pressure of the compressed gas is 10 to 50 atü. A further description of a suitable air nozzle can be found in the at the same time pending application @ 17 85 158.0 dated Aug. 17, 1968.

The thread bundles are in their gas jets from the exhaust pipe Cheese driven towards the storage surface as shown in Fig. 3.

An air extractor is under the gas-permeable shelf surface provided to evacuate some of the air blown onto the shelf surface.

Eiu thread bundle or sub-bundle running at high speeds Driven against the filing surface can result in further smaller sub-bundles split, as will be described in more detail below, which then rebound and form a vortex layer of intermingling bundles and sub-bundles which then again filed in the characteristic manner described below will. At the points of overlap, the vortex threads of the adjacent ones are linked Air nozzles effectively create an endless, even, unlayered overlapping Part.

The way and catfish in which the filing is done to the desired evenly Achieving strong, uncoated fleece is the key feature of the present Invention. Some definitions and theoretical considerations regarding the fleece properties are useful in this context.

A textile fleece can be described by two parameters, regardless of its structure, namely the thread weight f of the fleece web, weighted in grams, and the denier of the thread used (denier defined as the gram weight of a 9,000 m long thread). These two parameters can be combined to define the "specific thread length 11 1, where 1 is the total thread length that has been stored in a unit of area.

The "specific thread length" 1 is independent of the fleece structure, d. H. for example, a certain value for 1 could be the result of dropping a single thread or a plurality of threads consisting of one or more Air nozzles emerge.

The weight per unit area (fi) of the fleece produced by a single air nozzle can be calculated from the following variables: n = number of threads per air nozzle; b "Width of the deposited individual web per air nozzle (m); vs longitudinal speed of the deposit surface (m / min); gi- throughput per multi-hole spinning nozzle (g / hole / min) 0 The basis weight is then defined as follows: The formula is given for the weight per unit area f of a fleece consisting of several individual webs which has been extended by a number of air nozzles where m = number of air nozzles and B - width of the conveyor belt (in rivets) on which the deposit takes place.

If the air nozzles are arranged so that a shelf is adjacent, but does not result from overlapping individual paths, then it is clear that f + = f, i.e. that is, the basis weight produced by a single air nozzle is equal to the total produced basis weight. If now f is less than f, the discarded Individual tracks overlap and the degree of divergence between f and £ + is a measure the degree of overlap. Generally this maintains according to the present invention produced fleece to have a ratio f / f + of 2: 1 to 4: 1.

The specific thread length 1 can also be expressed in the other variable sizes given above. if where Wa is the thread withdrawal speed (m / nin), the combination of definitions (1), (2), and (4) becomes where 1 + is the specific thread length produced by a single air nozzle. The definitions (1), (3) and (4) combine to form the total of the deposited fleece Again, 1 = 1 + for adjacent non-overlapping individual webs and 1 is greater than 1+ for overlapping, that is, in an overlapped fleece, the length of thread deposited per unit area is greater than in a single individual web, deposited separately by only one air nozzle.

As stated above, the efforts required the heretofore known Process engineering to achieve the overlap of the deposited individual webs Installation of air nozzles at intervals in the direction of the longitudinal movement of the shelf either by means of staggered groups of air nozzles that extend across the width extend the shelf at different points or by arranging the air nozzles diagonally across the width of the surface. It is clear that in both cases there is a stratification must occur d. that is, a single leg deposited by a single air nozzle is necessarily quiet is placed above or below the next adjacent single lane, insofar as the overlapping one Part of a single Binzelbahn is essentially completely formed before the overlapping part of the next single lane that forms afterwards is applied. Essentially, they are aggregated within the nonwoven structure Areas formed in which these agglomerations are much stronger than the gaps between the adjacent agglomerations are and the thickness of the total nonwoven web therefore becomes uneven. This also applies to the previous techniques (e.g. U.S. Patent 1,006,039) where the air nozzles were arranged so that the basis weight and the specific thread length was substantially uniform over the entire fleece, by gauging the principle of Gaussian distribution from a single air nozzle discarded threads served Cd. H. less thread deposit near the long edges a single lane than near their putty) and sufficient overlap to compensate the thread deposit provided over the entire width of a single lane. At the earlier known technique, this compensation required an overlap of 50 to 80% of two adjacent individual beams.

Despite such compensation, of course, has a stratification at the same time Unevenness in the thickness of the individual webs formed still occurred, despite the relatively even density of the fleece across the entire width.

The present invention avoids such stratification in that for simultaneous formation, mixing and overlapping; of thread liner, Loops and loops are taken care of in the adjacent stored individual tracks.

When laying down the nonwoven web according to the present invention, it overlaps a single lane the closest z. B.

by 50% of its width. In this way, a middle single lane, that is, one with laterally adjoining individual tracks, be completely overlapped. According to Fig. 5A, the overlap c must be at least 50% of the storage width b of a single lane.

If air nozzles are used that are in a plane transversely (or in Angle up to 450) to the direction of movement of the storage surface to and fro, then the individual web width b is measured over the widest air cone area (see Sect. Fig. 5B). In Fig. 5B, the shaded parts represent the cross-section of the air cone the area that is created by moving the air nozzle back and forth from its middle (unshaded) position is crossed out, and the overlap distance c becomes more closely overlapping between the endpoints of the widest area Air cone measured. It is possible to have an overlap much greater than 50 % between adjacent individual lanes. As shown in de- r Fig. 5C, the overlap width c can approach the width b so far that the both widths are almost the same. In such a place there can be dropped parts like z. B. d in Fig. 50, where the shelf consists of at least three air nozzles he follows. In any case, however, the overlap distance c must be at least 50%, if possible but 70 yo of the individual web width b, regardless of whether the air nozzles to and fro or not. It is clear, however, that the use of reciprocating Air nozzles generally have a wider swept area, i. H. a larger single lane width b and a greater degree of multiple overlap (filing of three and more Air nozzles in a single tray) sten. With a Such a multiple overlap creates a particularly strong and uniform fleece achieved.

In the present invention, there is overlap without stratification thereby achieves that the air nozzles in a straight line over the moving Conveyor belt d. H. right to the direction of the longitudinal movement of the deposit belt, arranged to precede an overlapping series of air jets as shown in Fig. 5. In the case of stationary, i.e. H. air nozzles or air cones not swinging back and forth Overlapping of adjacent air jets, which are generated by adjacent air nozzles, thereby regulating the distance between the air nozzle and the shelf so that the Air jets that extend outside the air nozzle to the shelf and in doing so, assume a conical shape, overlap each other to the desired extent as soon as they hit the said surface.

This is illustrated in Fig. 5. Since a jet of air from a Lurtiüse in a natural expansion angle (e.g.

from about 50 to about 700 from the vertical), the The storage width of a single lane depends only on the distance between the exhaust pipe the air nozzle and the shelf surface. To that of the present invention To achieve the required degree of overlap, a distance of 0.3 to 1.5 will be required Meters between the air nozzle and the shelf, the air nozzles at intervals 6 cm apart.

In a practical embodiment of the present invention, commute the air nozzles when depositing the thread bundles back and forth. The pendulum level can be sideways lying, d. H. across the direction of the longitudinal movement of the shelf or in an angle of up to 450 to it. In either case, that generated by each air nozzle is moving Air jet sideways across the width of a single lane, as shown in Figure 5B. When the air nozzles perform a pendulum motion, it becomes a particularly complete one Mixing of the fiber bundles and sub-bundles in the overlapped areas is achieved, insofar as the thread bundles and sub-bundles within the adjoining Air jets intertwine like shuffled cards, creating a strong and uniform bonding takes place on the overlapped surfaces. Another advantage the use of pendulous air nozzles is that.

one varies the width of the stored individual webs determined by a filing apparatus and the extent of the overlap by changing the pendulum amplitude. In commercially available embodiments, these pendulum amplitudes are approximately 5 to 70 mm. In addition, the pendulum frequency can be adjusted within various limits and can be optimally selected in order to achieve the desired type of storage and the desired degree of non-layered but lapping. The theoretically highest possible frequency (L max) that can be achieved when laying bundles of thread back and forth across the laying width, so that time is allowed to form loops on itself, is given by the following equation: where Wa is a withdrawal speed of the threads in m / min and (b) is the width of a single web. In this way, for example, a take-off speed of 4,000 m / min and a deposit width of 0.3 m enable a maximum frequency of 111 Hz.

At frequencies approaching its maximum, a normal becomes primary Loop pattern formed while at low frequencies the threads of this normal loop pattern and loops on themselves or smaller loops and form loops, as shown schematically in Fig. 6.

If the frequencies are reduced, a larger number is formed of intersection points of bundles of threads, sub-bundles and loops that connect to each other cross. As a result, the strength of the nonwoven material produced is increased. In order to produce a web according to the present invention, at least five times as much thread length is compacted in secondary loops and loops as required would be to form primary loops only. Therefore, in the present invention Oscillation frequencies up to 0.2 l'max required. It will be understood that in the calculation the pendulum speed as constant according to equation (7) above was accepted.

This is of course not entirely true, because the speed on the Reversal points are temporarily reduced to zero. Stopping can by expedient Apparatus changes are encountered in order to reduce the distribution of the basis weight to change and thus the weight per unit area over the entire width of a single strip balance. So it may be desirable to control the speed of the commuting Slowing air jets down when they move out of their center position, to excessively high thread application in the vicinity of the Niitte of such a single track avoid. Frequencies of 2 to 7 Hz have proven more practical in manufacture Nonwovens proven to be advantageous.

It is also possible to swing the ablation surface back and forth to the side under fixed overlapping nozzles or under simultaneously pending air nozzles to create the mixing effect in the overlapping areas still to be improved.

It becomes clear that a crucial relationship between those The speed at which the thread hits the storage surface (in length per unit of time) on, and the speed at which the shelf is steadily moving lengthways moved forward. If both speeds were the same, the fiber bundle would go out the air nozzle in a single linear movement in the direction of the shelf be filed.

If oscillating air nozzles are used, the minimum take-off speed must be used (WA) additionally take into account the limitation imposed on you by the above equation (7) is imposed to not just form primary loops across the width to ensure the storage surface back and forth, but also a sufficient length of thread cause so that a much larger length of thread condenses into loops and loops is.

To the typical image of the deposition of a nonwoven web according to the present In order to obtain the invention, it is necessary to (a) have a relatively high thread take-off speed comply with and (b) the Conveyor speed of the storage surface to be adjusted so that the specific thread length. (1+) at least 0.6 m / cm2, preferably but between 5 and 100 m / cm2, at a take-off speed WA and of a section width b, such specific thread lengths are obtained by adding the required deposit belt speed v calculated according to the above formula (5) and the speed thus calculated during the process of the method according to FIG of the present invention.

With a thread of a certain denier, the crucial thing can be said The relationship between the take-off speed and the speed of the depositing surface is also true Express as the specific thread weight f + (thread deposit per fleece in g / m2). That specific thread weight of the nonwoven material produced according to the present invention must be between 5 and 1 500 g / m2, but preferably between 10 and 1 000 g / m2, move. The specific thread length can be 1+ with a certain thread denier Calculate from the specific bath weight fourth according to the above definition (1) and the deposit surface speed required for a certain withdrawal speed WA can then be calculated using the above formula (5). Accordingly, certain So take-off speed and thread denier for a specific desired Filament weight required deposit surface speed.

By adhering to the variable operating sizes described above and storage conditions creates a typical fleece structure in the sense of the present Invention. On the question of the coarse structure of the thread bundle, Figure 6 shows the Arrangement of the thread bundles across the width of a single storage lane b.

It can be seen that the impacting on the storage surface Bundles of thread as a flattened loop back and forth across the width of a single strip distribute, with a large percentage (at least 80%) of the thread length increasing Smaller loops and loops compacted that touch with overlapping stitches. Of the Degree of opening of the primary loops is a function of Filing speed in relation to the oscillating thread deposit on the deposit belt, which in turn is a funlction the Schvzinglulgen is within the air jet or the jet itself. The number which hangs on the width of the primary loops forming smaller loops also depends on the withdrawal speed.

Figure 7 gives an answer to the question of the fine structure of the fleece material a schematic representation of the structure and distribution of a thread bundle with a multitude of parallel threads as soon as it hits the shelf. These parallel bundles of filaments are sometimes used while they are those described above Form smaller loops, split into smaller sub-bundles when opened, but they still contain a number of parallel threads, and occasionally Individual threads are also formed from these bundles and sub-bundles. It is it should be noted that parallelism is preserved in the formation of these sub-bundles (i.e.

two or more threads are going in the same direction and in the same In front of each other). The parallelism of the sub-bundles may be temporary are interrupted by a reversal point when the outer threads of a thread sub-bundle cross over on the inside so as to form the inner thread of continuous sub-bundles form. A turning point is formed where a number of threads of a sub-bundle cross each other at the same time. Figure 7A shows one out of an air nozzle blown parallel thread bundle that hits on the support surface a, possibly splits into several sub-bundles b, each of which is a smaller one Contains number of parallel threads, or splinters into a single thread c. The sub-bundles form loops such as B. d, which are related to each other about e or cross the original thread bundle or other sub-bundles at points E and f, Similarly, a single thread occasionally forms certain crossing points with primary bundles or sub-bundles or even crosses with itself. Off Figure 7B shows that a thread or sub-bundle b after Tying a loop d again can run in parallel with other thread sub-bundles and thereby the parallelism, which is a characteristic of the fine structure of the nonwoven material represents according to the present invention, even improved. In Fig. 7C, the possibility of repeated splinters of sub-bundles with parallel threads shown in further sub-bundles with a smaller number of parallel threads.

As soon as the fleece is completely on the shelf according to the present Invention rests, can the fleece by compression, heat sealing, needling and solidify and stabilize by latex treatment. The fleece leaves. z. B. Pre-compress between two pressure rollers to form a fabric-like material, which then is subjected again to compression at high temperatures. According to Fig. 2 it can u.B. guided over a heated roller and through a pressure belt machine sent. When running over the heated rollers, the temperature of the fleece should be slightly below the lowest limit of the melting point range of the plastic which the fleece is made of. Temperatures from 3 to 50 ° C below the melting point or the melting point range, but preferably from 5 to 300 ° C., are expedient. The setting of such a temperature causes crystallization of the polymer, It has been found that such a polycrystallization is a finished product with particularly high physical and chemical stability. The one on that Fleece as it runs over the heated roller (e.g. in a printing belt machine, etc.) The like.) The pressure to be exerted should be between 2 to 50 kg / cm2 or the line pressure 10 to 80 kg / cm.

The duration of the treatment of the nonwoven web under high temperatures and Pressing in a tape machine should be about 2 to 30 seconds and in a kind of extrusion machine be less than 2 seconds.

When the fleece baked goods have been hardened by heat treatment, the thread bundles at the thread intersection points of the intersecting thread bundle loops, which lie roughly in straight lines, welded together. Such short imaginary Lines are distributed over the surface of the nonwoven in an isotropic, but unaligned pattern. This pattern ensures low elongation, dimensional stability and unusually high tear strength of the products according to the present invention. The characteristics of the compressed fiber fleece or the fiber fleece film are in the Fig. 8 is a photomicrograph of such Fadnviiematerials according to of the present invention.

By changing the temperature, the printer and the temperature and the duration of the pressure changes the nature of the nonwoven material thus consolidated change. For example, the application can take a relatively long treatment time result in a paper-like sheet material at high pressure and high temperature, in which the polymer is oriented isotropically. In contrast to the conventional one The method produced sheet material can be that according to the present invention Proposed film material as described for normal paper, but not by hand be torn. In such a paper sheet material, the fibrous nature is the Fleece material largely switched off. It's either see-through or translucent and has a smooth, dense surface. Paper-like nonwoven webs are preferred from a polymer from that consisting of polyolefins, polyamides and polyesters Group selected.

On the other hand, the non-woven character of the deposited non-woven film can be determined substantially preserved when the conditions of compaction and consolidation are proportionate are mild, d. H. if only under moderate temperatures and pressures and not too to be treated for a long time. Nonwoven webs consolidated under such conditions are air- and permeable to water and have a fibrous structure. Such a thing Fleece can be heat-sealed on one or both sides.

The physical properties of the bonded nonwoven thread leave also change by the fact that you have a location z. B. of woven fabric between the press band is inserted, which then presses onto the nonwoven web while it is through the high pressure and temperature zone is running. The pattern of this situation expresses itself Nonwoven web on and on, so that the appearance of the thus consolidated nonwoven web the appearance of the woven intermediate layer: result in layers of coarse, porous woven fabric ie porous or perforated film material.

Amazingly, such properties could be found in the nonwoven material can only be conveyed unilaterally through heat treatment.

The fleece material can be achieved through the use of appropriate textile layers a decorative relief can also be given.

The ability of this process to have a number of largely different Nonwoven products with different properties compared to the previously known are novel to produce, is in itself a significant advantage in technology It becomes clear that a whole range of products with one and the same device can be made, and that this device works much more simply than that usual processing machines, such as. B. papermaking machines, stretching machines and the like

The apparatus for performing the method described above consists essentially from a variety of spinning devices, such as. B. multi-hole spinnerets, through which thermoplastic material is extruded into threads, as well as take-off devices, in which the threads are pulled off by air nozzles and placed on a moving one Shelf, e.g. B a conveyor belt, to be blown.

A deeper understanding of the device according to the present invention Invention and the following examples are shown in Fig. 1, which shows the formation of the Nonwoven film according to the present invention shows and Fig. 2 shows a flow sheet represents, in which the individual stages of the process flow and the most important Parts of the apparatus are shown as they are in the method according to the present invention Invention can be used. In Fig. 3 a delivery nozzle is shown, which the thread withdraws, stretches and blows out.

According to Fig. 1, thermoplastic material is fed into the extruder (100) introduced, melted and extruded The extruder is driven by a motor 101. The extruded material is fed into the multi-hole spinneret by means of a pump 103 pumped. The threads that are formed are drawn off through an air nozzle 2, which passes through the inlets 2a is constantly fed with pressurized propellant gas. In the I; u.ft nozzle 2, the compressed gas flows essentially parallel to the one from the guide tube ausve-trending threads without hitting them, so that they do not mix, but flow completely separately from each other. More precisely, the pressurized gas flows so that the threads spread and sub-bundles with also substantially parallel Form running threads.

The sub-bundles thus formed then hit the delivery conveyor belt 3, which moves on rollers 4. Between the outlet of the air nozzle 2 and the A guide plate 104 is arranged on tray 3. There is a suction chamber under the delivery belt 105 arranged, in which the air blowing onto the shelf 3 is at least partially sucked off will.

According to Fig. 2, molten thermoplastic material becomes extruded through the multi-hole spinneret 1 to form a bundle of threads, which then pass through an air nozzle 2 can be withdrawn, which is fed with compressed air through the air inlet 2a will. The bundle of threads is pulled out of the mouth piece of the air nozzle at high speed blown against the constantly moving conveyor belt 3, which is on Rolls 4 moved. The threads that are blown out are spiraled onto the themselves moving tape deposited, namely in the form of a thread fleece consisting of flax dumbbells, which extends over the entire width of the air cone generated by the air nozzle, The conveyor belt with the threads lying on it is pressed by a pair of rollers 5 and removed the fleece from the stripping roller 6 from the border band and can then one IYlaschine are fed, in which the raw fleece is heated and firmly pressed together will. The printing belt machine in Figk 2 consists of a heated roller 7, a Guide roller pair 9 and a tension roller 20, which stops the AnpreBband 8, the To keep fleece constantly pressed against the heated roller 7. Usually be the Suhrungsrolle 9 arranged in relation to the heated roller 7 so that the heated roller 7 to 30 to 80% of its circumference in contact with that in constant motion located and pressing against the fleece pressure belt. To a sticking To avoid the fleece material on the heated roller 7, it may be desirable to a concurrent layer 15 between the heated roller 7 and the run-through ends Insert fleece material, e.g. B. with the help of the delivery roll 13 and the take-off roll 14. This layer can consist of a suitable non-adhesive woven fabric. To As it passes through the printing belt machine, the finished nonwoven web is stripped from the pressure belt and taken from a second stripping roller 11 and then on the roller 12 as Finished product wound on.

Fig. 7 shows, like a cone of air, the ejected thread bundle contains through which emitted from the mouthpiece of the air nozzle 2 at high speed Air comes about. The air cone has a real round conical shape if the mouthpiece the air nozzle is circular. It can take on a pyramid shape if the mouthpiece is the Air nozzle is square or rectangular. The width b of the longitudinal section of the nonwoven web, which is deposited depends on the degree of divergence of the air cone, such as it flows out of the mouthpiece of the air nozzle, as well as from the distance h between the Mouthpiece of the air nozzle and the shelf.

Example 1 polypropylene granulate was melted in an extruder, who had a screw with a diameter of 45 mm and a length that was 28 times was as big as its diameter.

The polypropylene had a crystalline melting range of 160 to 164 ° C, a density of 0.906 g / cm3 and a SchmCl7j index i5 at 2300 C of approx. 5 before ES-truding. The extrusion took place under a pressure of 35 kg / cm2 and the lock had a temperature of 310 ° C at the exit. The spinneret possessed 300 nozzle outlets. The throughput was 0.66 g per outlet and minute. From The polypropylene threads exiting the spinneret were heated to a temperature below 600 C cooled and drawn off in bundles of 30 individual threads from ten air nozzles, the at an even distance from each other in a row at right angles to the direction of movement of the conveyor building, which was located 1.3 m below the nozzles, were arranged. the Air jets operated at a pressure of 22 atm. the air consumption was per nozzle 30 m3 and hour. The dimensions of the air nozzles were 2.0 mm # at the inlet tube and 4.3 mm on the outlet pipe. The threads were driven by a stream of air at one speed at a speed of approx. 520 m / sec through the air nozzles. The air jets commuted with one Frequency of 2 Hz.

The withdrawal speed of the thread entrained by the air stream was 4,000 m / min, which resulted in a titer of 1.5 den.

The strength of the 1.5 denier threads was 4.3 g / denier. The basis weight of the deposited nonwoven web was 85 g / m², which corresponds to a throughput speed of 10.8 kg / h corresponded. The delivery and conveyor belt was running at one speed moved forward by approx. 3 m / min. The endless strings were moving towards it located conveyor belt blown into tangled overlapping sub-bundles, each Contained 9 to 5 essentially parallel threads and formed a nonwoven web. The nonwoven web produced in this way consisted of a large number of side by side Longitudinal individual webs made of polypropylene thread, which are in the form of small sub-bundles with essentially parallel threads in a loop-like arrangement on the single track Distributed back and forth in a width of 0.25 m with a thread length of 5 m and overlapping several times over a single track in a loop-like arrangement secondary smaller loops and loops compacted. The adjacent individual Individual sheets overlapped by 65 to 70% of their width without layering. the Loops and loops of a single track mixed completely with them the individual lanes are attached. The basis weight of a nonwoven web segment deviated from the average weight of the entire nonwoven web by a maximum of 7%. The resulting nonwoven web had a Width of 70 cm and a very even structure For easier handling of the She was pressed between two rollers with a nonwoven web. This slightly compressed Nonwoven web. was then at a speed of 3 m / min (i.e. at the speed of the deposit belt) pulled through between the belt and the roller of the printing belt machine.

Example 2 Nylon 6 was made in the extruder described in Example 1 melted. The viscosity of the molten material was 2.6 rel at a Temperature of 2830 C. The extruder pressure was 60 atm. The multi-hole spinneret had 150 nozzle holes with a diameter of 0.6 mm each. The throughput per DwlsDenloch was 1.1 g / min. The nylon threads were blown with the air jet under the same operating conditions deducted as in example 1. The resulting thread withdrawal speed was 3,300 m / min, which corresponds to a titer of 3.0 den.

The weight per unit area of the laid nonwoven web was 350 g / m2.

The laid fleece web was needled under the following conditions: Needle type: 36 Needle depth: 17 mm stitches per cm2: 90 hoods per minute: 410 B. 0 i 5 p i e 1 ~ A polyester with a content of 0.4% by weight of titanium dioxide was melted in an extruder and processed as follows: Spinning conditions: extruder: 45 mm #; Length 126 cm (28d) multi-hole spinneret: 300 nozzle outlets Spinning temperature: 2750 C Number of air nozzles: 10 Throughput: 1.1 g per nozzle outlet and minute Thread take-off speed: 4,500 m / min Titer: 2.2 Denier Air pressure for the air nozzles: 25 Atm.

Inside diameter of the air jet: 2.5 mm Outside diameter of the air jet: 5.0 mm Weight per unit area: 100 g / m2 The nonwoven web produced and deposited in this way was at a Temperature of 1020 C and heat-sealed under low pressure and on both sides embossed.

Example 4 A polypropylene resin was used in the one described below Apparatus under the specified conditions according to that described in Example 1 Procedure processed; Extruder diameter: 120 mm Length: 360 mm Melting temperature: 2860 C Number of spinneret 1 412 outlets: (14 lanes with 108 outlets each) Number of air nozzles: 14 throughput: 1.5 g per outlet and laiinute titer: 3 denier Take-off speed: 3800 m / mi Thread tenacity: 3.6 g / den Elongation at break 129% Air nozzles: pressure 22 atm inlet- 3.0 mm outlet- 6.6 mm Air consumption: 80 m3 / h weight per unit area of the nonwoven web 100 g / m Example 5 Die Nonwoven web produced as described in Example 4 was consolidated and then the ribbon. and fed to the pressure roller of a bite sealing machine. The steel roller was heated to 1450 C and the pressure exerted by the tensioned belt was 150 atm. The steam-heated steel roller was 700 mm in diameter and turned 65 % of its circumference touched by the pressure tape.

The nonwoven web was heat sealed on both sides in two passes. The following properties of the nonwoven web were achieved: Strength, parallel breakage 1.82 kg / mm2 19% across 1.5 kg / mm2 12% tongue tensile strength parallel 0.056 kg / g / m2 across 0.057 kg / g / m2 Nonwoven web was the heat sealing machine in just one operation at one temperature fed to the steel roller at 1580 C and a pressure of 150 atm. That achieved Fleece had the following properties: strength, elongation at break, parallel 2.6 kg / mm2 38% across 2.2 kg / mm2 32% Tongue tear strength parallel 0.030 kg / g / m² across 0.026 kg / g / m2 EXAMPLE 7 The table below shows such as the take-off speed, which is determined by the construction of the equipment and the operating conditions the air nozzles can be influenced, including the properties of the threads produced Affects: Product: Polypropylene nozzle hole diameter 0.6 mm: Length: double Diameter drawing speed strength elongation titer m / min) (g / den) (%) (denier) 2000 2.30 217 16.5 2500 2.75 174 13.5 3000 3.20 150 11.3 3500 2.54 135 9.5 4000 3.78 130 8.5 B e i s p i e l 8 One under the conditions mentioned in Example 4 produced fleece, which however has a lower weight per unit area of 80 g / Z2 (due to correspondingly increased depositing speed) was used with a commercially available Latex (No. 9210) from Synthomer Chemie, Germany, treated. The basis weight of the non-woven fabric after the latex treatment was then 192 g / m² and the non-woven fabric itself had the following properties: Strength Before latex treatment After parallel 1.2 kg 9.4 kg across 1.3 kg 9.7 kg mean stretch 7% 28%

Claims (1)

P a t e n t a n s p r ü c h e 1) Endless thread fleece from a variety single lanes running alongside one another, characterized in that each individual lane from at least 15 continuously and jointly spun and drawn synthetic There is thread, which is in the form of smaller sub-bundles of essentially parallel threads are distributed back and forth like loops over the width of the individual webs, one being essential greater thread length of at least 500% in said loop-shaped arrangement compacted as multiple overlapping secondary smaller loops and loops is, the side-by-side single tracks move without stratification by at least The secondary loops and loops of a single panel overlap 50% of their width completely confused with those of the overlapping part of the ones running next to each other Mix the individual lanes, the weight of the fleece on the overlapping parts of the individual lanes varies by a maximum of 20% of the total fleece weight, and the individual Nonwoven-forming threads have a titer of 1 to 20 denier and a tensile strength of 0.5 to 6 g / den and d-EF fleece has a weight of 10 to 1 500 g / m² 2) Fleece according to Claim 1, characterized in that the threads are oriented polyolefin threads are. 3) fleece according to claim 2, characterized in that the threads are oriented Polypropylene threads are. 4) fleece according to claim 2, characterized in that the threads are polyethylene threads are. 5) fleece according to claim 2, characterized in that the threads are polybutylene threads are. 6) fleece according to claim 1, characterized in that the threads are polyamide threads are. 7) fleece according to claim 1, characterized in that the threads are polyester threads are. 8) fleece according to claim 1, characterized in that the threads of copolymer are made of polyolefins. 9) fleece according to claim 1, characterized in that the threads are mixtures of polyolefins, polyamides and polyester are o 10) Nonwoven thread fleece according to claims 1 to 9, characterized by at least 5 parallel overlapping and 70 to 300 mm wide individual webs, in which the overlapped parts are approx. 35 to 240 mm wide. 11) Nonwoven thread fleece according to claims 1 to 9, characterized through at least 35 parallel, overlapping and 180 to 300 mm wide individual strips, in which the overlapped parts are approx. E £ 0 to 240 mm wide. 12) Nonwoven thread fleece according to claims 1 to 11, characterized characterized in that a substantial number of the sub-bundles are substantially more parallel Threads are welded together at their crossing points. 13) Nonwoven thread fleece according to claims 1 to 12, characterized by a binder that has a substantial number of the sub-bundles much more parallel Threads stuck together at their croazing point. 14) Nonwoven thread fleece according to claims 1 to 13, characterized characterized in that loop-like arrangements formed from flattened loops that extend over single lane widths and forth, the length of the parallel thread bundles, which form the flattened loops, to multiply secondary loops and loops compacted. 15) Method for producing a nonwoven thread fleece according to claims 1 to 14, characterized by the spinning of a plurality of filaments made of synthetic polymer, stretching and peeling off the bundle with a Speed of at least 3,000 m / min within one she surrounding and beam ejected at supersonic speed, which is directed so that it strikes vertically on a substantially horizontal storage surface, wherein the @@ adel and the gas jets surrounding it in a straight line over the tray @@@@ he and are arranged at right angles to their Fahrtri f ~ + tUslg, the setting of the Jets of gas in such a way that the edge of each jet on the shelf is the edge of the adjacent jet by at least 50% of the total width of the individual gas jet overlaps on the shelf, the speed of the conveyor belt movement being significant is set lower than the speed at which the threads are drawn off so that the threads within the gas jet enveloping the bundle are looped and transversely to the direction of the depositing belt and with the formation of multiple overlapping secondary ones Lay loops and loops in a thread quantity of approx. 10 to 1,500 g / m² and In this way, create a non-woven fleece on the shelf, on which the adjacent Edges of the individual webs formed from the individual bundles without layers and overlap when completely mixed. 16) Method according to claim 15, characterized in that within of the gas jets, at least some of the filaments are present in sub-bundles before they are deposited on the storage belt in the form of a fleece. 17) Method according to claims 15 and 16, characterized in that that the drawn filaments have a titer of about 1 to 20 denier and a tensile strength from 0.5 to 6 g / den. 18) Method according to claims 15 to 17, characterized in that that the threads are spun down from the melt through multi-hole spinnerets that they hit the shelf. 19) Method according to claims 15 to 18, characterized in that that the air jets in a direction transverse or at an angle of 90 ° to 45 ° to the direction of movement commute to the shelf. 20) Method according to claim 19, characterized in that the air jets at the same time across the width of said shelf at an angle of 0 ° to Swing back and forth 45 ° to the direction of movement of said shelf and thereby move the surface significantly increase the beam contact with the shelf. 21) Method according to claims 15 to 20, characterized in that that the polymer becomes oriented threads with a titer of 1 to 20 denier and a tensile strength of at least 0.5 g / den is spun and drawn. 22) Method according to claim 21, characterized in that the polymer is a polyolefin. 23) Method according to claim 21, characterized in that the polymer is a polypropylene. 24) Method according to claim 21, characterized in that the polymer Is polyethylene. 25) Method according to claim 21, characterized in that the polymer Is polybutylene. 26) Method according to claim 21, characterized in that the polymer is a polyamide. 27) Method according to claim 21, characterized in that the polymer is a polyester. 28) Method according to claim 21, characterized in that the polymer @@@@@@@ @@@@@@@@@@@ @@@@@@@@@@ is. 30) Method according to claims 16 to 29, characterized in that that the threads are set up in sub-bundles of about 3 to 25 threads each. 31) Method according to claims 15 to 30, characterized in that that the threads are divided into a series of at least 5 curls and nG these Bundles within said gas jet on the deposit belt as parallel overlapping Individual lanes with a width of 70 to 300 mm each are deposited, with the adjacent overlapping individual web sections have a width of approx. 35 to 240 mm. 32) Method according to claims 15 to 31, characterized in that that the threads are sucked off at a speed of approx. 3,000 to 8 CJOO m / min and be stretched. 33) Method according to claims 15 to 31, characterized in that that 'the threads are pulled off at a rate of about 30 ° C! 0 to 5,000 mAnin and are stretched 34) Process according to Claims 15 to 33, characterized in that that the nonwoven thread fleece produced was needled 35) method according to the Claims 1 to 34, characterized in that on the produced non-woven Nonwoven fabric is subjected to heat and pressure, thereby creating a substantial number of sub-bands welding parallel threads together at their crossing points. 36) Method according to claims 15 to 35, characterized in that that a winter agent is worked into the non-woven thread fleece produced, so that a substantial number of essentially parallel fibers are put together as 37) Method according to claims 15 to 36, characterized in that @@@ das manufactured non-woven thread fleece with F @@@@ very @@ @@@@@ 38) device for the production of non-woven thread fleeces from thermoplastic threads through a series of multi-hole spinnerets that are continuously spun thermoplastic Able to extrude threads at a speed of 1 to 12 g / min; one Multiple exhaust and air nozzles in a single non-staggered row are arranged, each air nozzle at least 15 threads at one speed of at least 3,000 m / min to form a ribbon and a gas jet in which contains such elli fiber bundles to blow out at supersonic speed able; an air-permeable storage and conveyor belt below said row of air nozzles, that extends continuously and lengthwise in a direction transverse to the Luftdüschreihe moves whoever arranges the air nozzles in relation to the delivery and conveyor belt are that the gas jet blown out by an air nozzle the deposit and conveyor belt touched and with the found each gas jet] .s on the conveyor belt and the hand of the Air jet from the next adjacent air and exhaust nozzle in the row by at least Overlap 50% of the total width of the individual haul-off and air jets on the delivery belt. 39) Apparatus according to claim 38, characterized in that each said deposit and air nozzles on an axis parallel to the plane of the deposit belt is arranged swinging and an angle of 0 ° to 45 ° with the line of longitudinal movement of the depositing belt to oscillate at a constant frequency of 2 to 7 Hz. 40) Apparatus according to claim 39, characterized in that the Angle is 0o. 41) Apparatus according to claim 38, characterized in that the The amplitude of the pendulum movement is 25 mm. 42) Apparatus according to claim 38, characterized in that between the row of air nozzles and the storage level @@ e @@ ntbleche s as below the storage belt a suction chamber is provided to remove the air blown onto the deposit belt suction to a part