EP1776496A1

EP1776496A1 - Moulded head and method for the production of a nonwoven fabric

Info

Publication number: EP1776496A1
Application number: EP05747189A
Authority: EP
Inventors: Raymond Norgaard; Morten Rise Hansen
Original assignee: Concert GmbH
Current assignee: Glatfelter Falkenhagen GmbH
Priority date: 2004-04-29
Filing date: 2005-04-29
Publication date: 2007-04-25
Also published as: JP2007534857A; US7690903B2; US20080241301A1; CN1981080A; CA2564858A1; JP4755641B2; DE102004021453A1; WO2005106091A1; CN1981080B

Abstract

The invention relates to a moulded head for a device which is used to produce a nonwoven fabric by placing fibres on a conveyor belt. Said device comprises a fibre feed mechanism which is connected to a fibre processing chamber comprising a lower placement opening which is used to discharge fibres. Interlocking needle rollers are arranged in a parallel manner in relation to each other about the longitudinal axis in the fibre processing chamber, said interlocking needle rollers being able to rotate about the respective longitudinal axis thereof, surround the inner chamber and are arranged in such a manner in relation to the fibre feed mechanism and the placement opening, such that, during operation, fibres supplied to the moulded head enter into the inner chamber between interlocking needle rollers and leave the inner chamber between interlocking needle rollers.

Description

Mold head and method for manufacturing a nonwoven fabric

The invention relates on the one hand to a molding head for a device for producing a nonwoven fabric and on the other hand to a method for preparing fibers for producing a nonwoven fabric. The molding head has at least one fiber feed that opens into a fiber processing space. The fiber processing room has a storage opening for the delivery of fibers, for example on a conventional, air-permeable conveyor belt, under which a so-called suction box is arranged. Several intermeshing needle rollers with longitudinal axes aligned parallel to one another are arranged in the fiber processing space. The needle rollers are rotatable about their longitudinal axis.

Accordingly, the method comprises as process steps the feeding of fibers to a molding head and the uniform distribution of the fibers on a conveyor belt by means of the molding head. Various types of molding heads and processes of this type are already known, for example from WO 99/36623 or WO 03/016605.

The nonwovens to be manufactured usually contain a mixture of natural fibers, e.g. Cellulose fibers made of cotton or loosened, already mechanically and / or chemically treated wood cellulose (fluff pulp), synthetic matrix fibers such as e.g. Polyester, polypropylene or viscose as well as synthetic binding fibers such as so-called bicomponent fibers and, for example, as absorbents so-called superabsorbent polymers in particle (SAP) or fiber form (SAF). Bicomponent fibers usually have a core that melts at higher temperatures (190-250 ° C), e.g. Polypropylene (PP) or polyethylene terephthalate (PET), which is made from a casing that melts at lower temperatures (140 ° C), e.g. Polyethylene (PE) surrounded or connected in another form (side-by-side, fibril type).

Such nonwovens are used, for example, as semi-finished products for the production of diapers and sanitary napkins, absorbent pads for the food industry or for insulation material.

An important process step in the manufacture of such a nonwoven is to deposit the fiber mixture as evenly as possible on an air-permeable conveyor or conveyor belt. This is done with the help of a forming head in which the fibers are mixed. The storage is supported by a suction device (suction box) below the conveyor belt, with which the fibers are sucked through the air-permeable conveyor belt to the conveyor belt. The tangled, but evenly deposited fiber mixtures are transported on the conveyor belt as a fiber bed for further processing in downstream process steps, for example the action of heat on the fiber bed, so that the polyethylene sheaths of the bicomponent fibers fuse and stick together. Treatment with latex can also be used. In addition, it is possible to lay several fiber bed layers on top of one another in order to produce, for example, a multi-layer or even a thicker fleece. The range of products that can be produced using conventional devices and processes is usually limited by the fact that they can only be used to process certain types of fibers or fiber lengths, so that the known processes and devices do not produce nonwovens that are both relatively short and contain relatively long fibers in a forming step. In the prior art, systems can be found in which the short and long fibers are deposited one behind the other (EP1 299 588) or with a card (WO 03/086709). Disadvantages here are the increased machine outlay and the low basis weights that can be achieved if the fibers are made available via a carding process.

The invention is therefore based on the object of specifying a device and a method which have a greater bandwidth with respect to the fibers to be processed and thus with respect to the products to be produced.

According to the invention, this object is achieved by a molding head of the type mentioned at the beginning, in which the intermeshing needle rollers enclose an interior and are arranged with respect to the fiber feed and the deposit opening in such a way that fibers fed to the molding head during operation enter the interior between intermeshing needle rollers and also leave the interior between interlocking needle rollers. The shaping head is therefore designed in such a way that the fibers to be processed have to pass at least twice, preferably several times, between intermeshing needle rollers on the way from the respective fiber feed to the deposit opening. The intermeshing needle rollers help to even out the fiber distribution in two ways. On the one hand, they simply result in an even distribution of already separated fibers. In addition, the interlocking needle rollers dissolve lumps of fibers consisting of interlocked fibers and in this way bring about further fiber separation. The latter can also be referred to as fiber opening. In this sense, the molding head according to the invention has a larger fiber opening capacity than known molding heads. Another advantage is that with the molding head according to the invention, both long natural, eg Cotton cellulose fibers as well as short natural ones, for example wood cellulose fibers or synthetic fibers, can be processed equally and in one step, in particular fibers with lengths between 2 and 60 mm. Fiber beds between, for example, 50 g / m ² and 2500 g / m ² can also be produced in one step with the molding head according to the invention. So far, different devices and methods have been required to process fibers of different lengths. For example, long-fiber fiber beds from 10 g / m ² to 80 g / m ² can be produced in one step with conventional molding heads using the carding process and short-fiber fiber beds from 50 g / m ² to 2000 g / m ² with the conventional air laying process.

In a preferred embodiment variant, the longitudinal axes of the needle rollers are connected to a rotatingly driven needle roller carrier, the axis of rotation of which runs parallel to the longitudinal axes of the needle rollers. In this way it is possible to have the needle rollers not only perform a rotational but also a translatory movement. The needle rollers are preferably each at the same distance from the axis of rotation of the needle roller carrier, and are thus arranged on an imaginary cylinder wall which belongs to a cylinder whose central axis is the axis of rotation of the needle roller carrier. The needle rollers are evenly distributed on this imaginary cylinder wall, so that they are at the same distance from each other. The fibers entering and exiting the interior thus pass between rotating and translationally moving needle rollers.

The rotational movement of the needle rollers is preferably such that adjacent needle rollers have an opposite direction of rotation, as is also the case for intermeshing gear wheels of a transmission. However, in a preferred embodiment variant, the interlocking needle rollers are not rigid, for example coupled to one another via gearwheels, but each have a separate drive and can therefore also be driven, for example, at different rotational speeds. For this purpose, the needles of adjacent needle rollers with respect to the needle roller longitudinal Axial direction offset so that the needles of adjacent needle rollers do not collide regardless of the respective speeds. The needles are preferably arranged in longitudinal rows on the needle rollers, particularly preferably alternately offset a little in the circumferential direction of the needle roller, so that there is a zigzag needle row in each case. The needles of the individual needle rollers each protrude from a cylindrical needle roller body to which the individual needles are attached.

Basically, the number of needle rollers enclosing a respective interior space is arbitrary and at least 4. An arrangement of 8 or 12 needle rollers has the advantage, however, that the transport direction in the space between the needle rollers, which is predetermined by the rotational movement of adjacent needle rollers with different directions of rotation, is such that the direction of transport in opposite gaps is opposite, that is, either towards one another (into the interior) or away from one another (out of the interior). The needle roller carrier preferably has a central shaft which is aligned concentrically to the axis of rotation of the needle roller carrier and thus on the one hand fills at least part of the interior and on the other hand also serves to transmit rotational forces along the shaft.

The fiber processing space of the molding head preferably has side and end walls in the area of the needle rollers, which enclose the needle rollers enclosing the interior in such a way that fibers flowing outside the needle rollers past the interior are largely prevented. In addition, the side walls running parallel to the axis of rotation and the longitudinal direction of the needle rollers above the interior are preferably bent towards one another in such a way that a fiber inlet opening narrows relative to the outer diameter of the entirety of the needle rollers enclosing the interior. This fiber inlet opening is preferably dimensioned such that it corresponds to approximately 1.5 to 2.5 times the free space that exists between roller bodies of adjacent needle rollers. Such a fiber inlet opening helps to even out a fiber flow and also an air flow through the interior. The fiber inlet opening is preferably arranged centrally above the interior, so that the fibers are fed as centrally as possible to the rotating, intermeshing and translationally moved needle rollers.

A screen is preferably arranged underneath the interior and assigned to the deposit opening. This screen preferably runs along an imaginary cylinder wall segment, which corresponds to an imaginary cylinder, the central axis of which is the axis of rotation of the needle roller carrier.

When using longer fibers with a length of 10 to 60 mm, the sieve is preferably formed by sieve bars which run at least approximately parallel to one another and to the longitudinal axes of the needle rollers and which preferably have a round cross section. The cross section of the sieve bars is preferably selected so that its diameter corresponds to approximately half the fiber length of the longest fibers to be processed. The distance between the sieve bars also preferably corresponds to half the fiber length of the longest fibers to be processed. Such a sieve acts in the aerodynamic sense as a diffuser and thus helps to even out the air flow below the interior. This creates a uniform air flow for a fiber bed placed on the conveyor belt between the fiber feed for the fibers to be processed and the suction box below the conveyor belt.

When using shorter fibers with a length of up to 10 mm, the sieve is formed from well-known wire mesh or steel plates with regular, repeating, geometric openings. Opening shapes can be round, stadium-shaped (oval) or rectangular. Their number, size and arrangement depend on the desired degree of opening, the ratio between the passage area and the total area of the sieve.

According to the devices described so far, the above-mentioned object is also achieved by a method of the type mentioned in the introduction, in which not only a distribution of already separated fibers in the molding head, but also an opening of fiber lumps and thus a separation of fibers takes place with the help of rotating, interlocking needle rollers. The fibers are guided between rotating and intermeshing needle rollers into an interior and then leave this interior between rotating, intermeshing needle rollers.

For this purpose, the needle rollers are preferably moved transversely to the axis of rotation of the needle rollers while the fibers are being fed to the interior. The movement of the needle rollers (rotary and translatory) is preferably set such that the fibers or at least some of the fibers are fed into the interior several times before the fibers leave a fiber processing space in which the interior is located.

In addition, to carry out the method, an air stream is preferably generated which passes through the interior from top to bottom. This air flow is preferably evened out through a sieve below the interior. In addition, the air flow is preferably passed above the interior through a fiber inlet opening narrowed relative to the interior. This also helps to even out the air flow. The invention will now be explained in more detail using an exemplary embodiment.

From the figures show:

Figure 1: a section of a system for producing a nonwoven fabric with a molding head according to the invention; and

FIG. 2: a top view of the molding head from FIG. 1.

The system 10 shown in FIG. 1 for producing a nonwoven fabric comprises a molding head 12 which is arranged above a conveyor belt 14. The conveyor belt 14 is permeable to air. The molding head 12 has a lower storage opening 16 above the conveyor belt 14. A suction box 18 is arranged below the conveyor belt 14 and below the storage opening 16. With the aid of the suction box 18, a directed air flow can be generated through the molding head 12 out of its storage opening 16, through the conveyor belt 14 and into the suction box 18.

With the help of the air flow, fibers deposited by the molding head 12 on the conveyor belt 14 can be safely sucked onto the conveyor belt 14. Fibers deposited by the forming head 12 on the conveyor belt 14 form a fiber bed (not shown) on the conveyor belt 14. By continuously driving the conveyor belt 14, a continuous fiber bed can be produced on the conveyor belt 14 if fibers from the forming head 12 are simultaneously deposited on the conveyor belt 14. This continuously produced fiber bed is fed to further processing stages, not shown in FIG. 1, for example those in which the fiber bed is subsequently pressed.

Further, subsequent connection techniques are conceivable; they depend on the required properties of the product, such as a low adhesive content or high tear resistance, even when wet. In addition to water jet consolidation, "application of high pressures at selected points, hydrogen bonding also ultrasound bonding, bonding by heating, e.g. with hot air and the use of latex dispersions.

The fibers forming a respective fiber bed are usually natural, for example cellulose fibers mixed with synthetic fibers, for example so-called bicomponent fibers. The latter preferably have a core made of PET or PP and are surrounded by a jacket made of PE. When heated, the PE jacket melts and causes a respective bicomponent fiber to combine with a natural or synthetic neighboring fiber or functional components. Such functional components of the fiber bed that are fed to the forming head 12 can be, for example, superabsorbent polymers (SAP), which lead to the fact that liquids can be bound efficiently by means of a fiber fleece produced in this way. This property is particularly desirable when if the nonwoven is to be processed into absorbent articles such as diapers, sanitary napkins or absorbent pads.

The shaping head 12 encloses a fiber processing space 20 into which one or more fiber feeds 22 open - only one such fiber feed 22 is shown in FIG. With several fiber feeds, fibers of different types, for example cellulose fibers or bicomponent fibers, as well as other substances to be fed to the fiber bed, such as SAP or odor-absorbing constituents, can be fed in independently of one another. The fiber feed 22 ensures a uniform feed of pre-opened fibers over the entire width of the fiber processing space 20, see FIG. 2.

In a preferred embodiment variant, a volumetric metering unit is provided as the fiber feed, which is arranged centrally above the fiber processing space 20, that is to say not laterally, as shown in the figures. In the preferred embodiment variant, the fiber is thus fed into the fiber processing space from above.

A needle roller carrier 26, which is shown in FIG. 1 only by its central drive shaft 24 and which carries eight needle rollers 28 evenly distributed on an imaginary cylinder jacket surface, is arranged in the fiber processing space 20. The cylindrical outer surface of the needle roller carrier 26 is indicated by the dash-dotted line labeled 26. The needle roller carrier 26 can be seen better in FIG.

Each of the needle rollers 28 has a needle roller body 30 with attached needles 32 arranged in rows in the longitudinal direction of the needle roller body 30. The needles have a diameter between 1 and 6 mm and preferably between 2 and 4 mm. The distance between the needles 32 within a row is between 10 and 20 mm and is typically on the order of 15 mm. The needle rollers 28 engage, as shown in Figure 1, and enclose an interior 34th

The needle roller carrier 26 can be rotated about its central shaft 24 in such a way that all of the needle rollers 28 can be moved in a circle on the path indicated by dash-dotted lines. For this purpose, the needle roller carrier 26 has a central electric drive motor 36.

Each needle roller 28 is driven by its own electric motor 38, so that the needle rollers 28 can rotate independently of one another. As can be seen in FIG. 2, the needles 32 of adjacent needle rollers are offset from one another in the longitudinal direction of the needle rollers, so that the needles 32 of adjacent needle rollers do not collide with one another when the needle rollers 28 rotate independently of one another.

Between the roller bodies 30 of adjacent needle rollers 28 there is a free space 40, into which the needles 32 of the adjacent needle rollers 28 penetrate. Fibers, which are fed in the fiber processing space 20 by means of the feed 22 above the needle rollers 28 and thus above the interior 34, must enter the interior 34 through the respective free space 40 and thus between intermeshing needle rollers 28. Likewise, fibers must leave the interior 34 again through one or more of the free spaces 40 between the adjacent needle rollers 28.

Fibers fed to the fiber processing space 20 above the interior 34 by means of the fiber feed 22 must therefore pass through the spaces 40 between adjacent needle rollers 28 at least twice before the fibers leave the fiber processing space 20 in the area of the deposit opening 16. The fibers pass through the interior 34. In operation, both the needle roller carrier 26 and the needle rollers 28 are driven in rotation, so that each needle roller 28 simultaneously rotates. tion and a translational movement along the dash-dotted line.

Adjacent needle rollers 28 are driven in opposite directions of rotation, so that they behave at the same speed as meshing gears. For a respective free space 40, this leads to the needles 32 projecting into the free space 40 specifying a fiber transport direction which is either directed into the interior 34 or out of it. In this way, fibers can enter and be conveyed out of the interior 34 several times in the desired manner before they finally leave the fiber processing space 20 through the deposit opening 16.

The number of 8 needle rollers shown in FIG. 1, as well as an alternatively possible number of 12 or 16 needle rollers, has the advantage that the transport direction within diametrically opposite free spaces 40 is opposite, so that fibers in the situation shown by way of example in FIG. 1 do not pass through the upper free space transported into the interior 34 and immediately leave the interior 34 again through the lower free space.

In order to even out the fiber bed to be produced with the aid of the forming head 12, a cylinder-like curved screen 42 is provided below the needle rollers 28. In the embodiment variant of the molding head preferred for the processing of longer fibers, this sieve is formed by a multiplicity of rods running parallel to the longitudinal axes of the needle rollers 28 and the axis of rotation of the needle roller carrier. These rods have a circular cross section and a diameter of 2 cm. The distance between the bars is also 2 cm. Such a sieve is suitable for fibers with a maximum fiber length (staple length) of approximately 40 mm. These are fiber lengths that are common with cotton fibers and with viscose staple fibers. As previously mentioned, sieves of conventional opening geometry, that is to say with round or oval holes or longitudinal slits, can also be provided for other types of fibers.

The distance of the screen 42 from the free ends of the needles 32 is between 1 and 30 mm and preferably between 1 and 10 mm.

To further even out the fiber flow, the side walls of the fiber processing space 20 are drawn inward in the area denoted by 46, so that there is a narrowed fiber inlet opening above the needle rollers 28. Their width, which can be seen in FIG. 1, corresponds approximately to 1.5 to 2.5 times the width of a respective free space 40 between adjacent needle rollers 28. Similar to the area 46 above the needle rollers 28, side wall regions 46a drawn in below the needle rollers 28 can also be provided his.

Furthermore, the gussets remaining between the optionally drawn-in side walls of the fiber processing space 20 and the needle rollers can be provided with fiber guide bodies 48 which limit the free space between a respective side wall and the needle rollers. These fiber guide bodies 48 are connected to the needle roller carrier 26 and rotate with it. Similar fiber guide bodies can also be arranged on the central shaft 24.

Freely rotating rollers, which are arranged on the underside of the side walls and seal the fiber processing space 20 below the sieve 42 with respect to the conveyor belt 14, are not shown.

With the device described above and its mode of operation, the following new products can be produced: A fleece for the production of tampons

Tampons are currently formed as nonwovens with long fiber materials using carding processes, i.e. H. the fibers are laid down in the longitudinal direction with the direction of advance of the endless storage belts. The directional laying form creates an imbalance in the tensile strength between the direction of advance and transverse to it. The tensile strength is higher in the longitudinal direction than in the transverse direction.

The long fibers of up to 60 mm deposited according to the method described in this application result in a different, more uniform strength, improved for the area of application, which has a positive effect on the article tampon.

For this purpose, the device according to the invention, the method according to the invention is used to produce a fiber bed from viscose fibers for tampons. These fibers are either so-called trilobal shaped fibers or conventional round fibers or a mixture of both. Typical fiber parameters are 1.7 to 6.7 dtex with a length ^J between 20 and 60 mm. A typical basis weight for a fleece for such an application is between 200 and 1000 g / m ² , depending on the tampon type. Cotton fibers are occasionally used for such fleeces for tampons. These fibers can also be processed with the described device and the described method. The final nonwoven can be composed of two or more layers. Each of these layers can contain fibers of different specifications. After the fiber bed has been formed, it is compacted with calender rolls and delivered in rolls or blocks as an intermediate product for the manufacture of finished tampons.

Nonwovens for the automotive industry

The device and the method described here also allow flax fibers or hemp fibers or similar natural fibers to be processed on their own or mixed with synthetic fibers. The fiber length of such natural rather fibers is typically 50 mm. Since these fibers are a natural product, there are also fibers that are shorter than 20 mm or longer than 120 mm. The synthetic fibers can be either polypropylene fibers or polyester fibers, the dtex values of which are between 1.7 and 20. The fiber length of the synthetic fibers is 12 to 38 mm for this product example. The basis weight of the corresponding nonwovens is typically between 1200 and 2500 g / m ² .

Träqeryliese as documents for further layers to be deposited

It is also possible to produce carrier webs with a basis weight of 40 to 100 g / m ² . In addition to the fibers mentioned above, the fibers used here are synthetic binding fibers, in particular so-called bicomponent fibers, whose dtex values are between 1, 7 and 20. The fiber length of the synthetic binding fibers is 3 to 36 mm. The backing nonwovens can be the base for further layers to be deposited with functional components, since they act as compacted backing nonwovens for fibers and / or components like collecting filters. For this purpose, the carrier fleece is unwound on the conveyor belt 14 and the fibers and / or functional components are deposited on the carrier fleece instead of on the conveyor belt.

Nonwovens for hygiene items such as baby diapers. Sanitary napkins. Incontinence products and the like.

In the case of the above-mentioned hygiene articles, there is a side facing the body. For this purpose, special nonwovens are used, which quickly transport the liquid into the underlying absorbent core. A fiber bed which contains polyester fibers is produced in order to produce such acquisition webs (acquisition or intake layer). These polyester fibers have dtex values between 3.3 and 16.7 and a fiber length between 24 and 36 mm. After the fiber bed has been formed, the fibers are bound with styrene butadiene rubber (SBR = styrene butadiene rubber) or with another binder such as EVA (ethylene vinyl nyl acetate) or an acrylic. A typical basis weight for such nonwovens for hygiene articles is between 20 and 100 g / m ² .

Nonwovens for use as moist cosmetic skin care wipes

The described device and the method can also be used to produce a fleece which contains polypropylene fibers or polyester fibers with dtex values between 1.0 and 3.3 and fiber lengths between 24 and 38 mm. For the purpose of liquid absorption, viscose fibers or loosened wood cellulose pulp fibers (fluff pulp) can be mixed with the polypropylene or polyester fibers, either as a uniform mixture or in layers. In subsequent processing steps, the nonwoven is hydroentangled or matted in some other way. Latex can also be applied to one or both surfaces of the nonwoven to prevent linting.

The four product variations described last show the wide range of nonwovens that can be created using the described molding head. Products of this type cannot be produced with known airform processes and therefore represent new (intermediate) products themselves.

Claims

claims

1. Forming head for a device for producing a nonwoven fabric by depositing fibers on a conveyor belt, with a fiber feed that opens into a fiber processing space, which has a lower storage opening for the delivery of fibers, wherein intermeshing needle rollers with longitudinal axes aligned parallel to one another are arranged in the fiber processing space are that can rotate about their respective longitudinal axis, characterized in that the interlocking needle rollers (28) enclose an interior (34), the fiber feed (22) being arranged outside the interior (34) in such a way that the molding head (12) ^{■ •} "have to pass to enter the direction into the interior space in operation supplied fibers between interlocking needle rollers (28) in the transverse verlaufen- to the longitudinal axes of the needle rollers and the inner space (34) also between mating needle rollers (28) into a turn, transverse to the Longitudinal axes of the N must pass through the direction of the noble rollers.

2. Molding head according to claim 1, characterized in that the longitudinal axes of the needle rollers are connected to a rotatingly driven needle roller carrier, the axis of rotation of which runs parallel to the longitudinal axes of the needle rollers.

3. Molding head according to claim 2, characterized in that the longitudinal axes of the needle rollers each have the same distance from the axis of rotation of the needle roller carrier.

4. Molding head according to one of claims 1 to 3, characterized in that the longitudinal axes of the needle rollers each have the same distance from one another.

5. Molding head according to one of claims 1 to 4, characterized in that a sieve is arranged below the needle rollers and the deposit opening.

6. Molding head according to claim 5, characterized in that the sieve is arranged like a cylinder wall segment below the interior.

7. Molding head according to claim 2 and claim 5 or 6, characterized in that the screen is shaped in the manner of a cylinder wall segment of a cylinder, the cylinder center axis of which at least approximately coincides with the axis of rotation of the needle roller carrier.

8. Forming head according to one of claims 5 to 7, characterized in that the sieve is formed by sieve bars running at least approximately parallel to the longitudinal axes of the needle rollers.

9. Molding head according to claim 8, characterized in that the sieve bars have a round cross section.

10. Molding head according to claim 8 or 9, characterized in that the sieve bars have a diameter which is matched to the length of the fibers to be processed such that the diameter corresponds to approximately half the length of the longest fibers to be processed.

11. Molding head according to one of claims 8 to 10, characterized in that the sieve bars have a distance from one another which is matched to the length of the fibers to be processed such that the distance of the sieve bars from each other is approximately half the length of the longest fibers to be processed equivalent.

12. Forming head according to one of claims 1 to 11, characterized in that the fiber processing space in the area of the needle rollers is closed laterally by side and end walls in such a way that the end walls run the interior transverse to the longitudinal direction of the needle rollers, while the side walls are parallel to run along the longitudinal axes of the needle rollers, the end and side walls being arranged with respect to the needle rollers in such a way that fibers flowing past the interior enclosed by the needle rollers is largely avoided.

13. Molding head according to claim 12, characterized in that the side walls above the needle rollers are bent towards each other to close enough to the needle rollers, so that a fiber inlet opening is formed above the needle rollers.

14. Molding head according to claim 13, characterized in that the needle rollers have a closed roller body and the needle projecting therefrom, so that there is a free space between the roller bodies of adjacent needle rollers, the fiber inlet opening being approximately 1.5 to 2.5 times as much is as large as the space between the roller bodies of immediately adjacent needle rollers.

15. Forming head according to one of claims 1 to 14, characterized in that the needle rollers distributed over their respective circumference have a plurality of rows of needles of radially projecting needles which run along the longitudinal axis of the needle roller and which, in the case of adjacent, intermeshing needle rollers along the respective row of needles, have such a reference the adjacent needle roller is arranged offset in the longitudinal direction so that the intermeshing needle rollers can rotate independently of one another.

16. Molding head according to one of claims 1 to 15, characterized in that the needle rollers distributed over their respective circumference a plurality of radial rows of needles running along the longitudinal axis of the needle roller have protruding needles, which are alternately arranged offset in the circumferential direction of the needle roller within a respective row of needles, so that there is in each case a zigzag-shaped row of needles.

17. Molding head according to one of claims 1 to 16, characterized in that the interior is enclosed by eight or twelve needle rollers.

18. Molding head according to one of claims 1 to 17, characterized in that a separate drive motor, preferably an electric motor, is provided for each drive roller.

19. Molding head according to one of claims 2 to 18, characterized in that the needle roller carrier has a shaft extending centrally through the interior.

20. A method for processing fibers by means of a forming head, in which the fibers are fed to a forming head and are deposited on the conveyor belt in an evenly distributed manner by means of the forming head, characterized in that in the forming head also a separation of fibers by opening clumps of fibers by means of interlocking fibers , rotating needle rollers is carried out in such a way that the fibers are fed into an interior of the forming head, which is surrounded by rotating needle rollers, between intermeshing, rotating needle rollers and then leave the interior again by the intermeshing, rotating needle rollers.

21. The method according to claim 20, characterized in that the needle rollers are moved transversely to their axis of rotation during the feeding of the fibers.

22. The method according to claim 20 or 21, characterized in that the fibers or at least part of the fibers multiple times the interior be guided before the fibers leave a fiber processing space, within which the interior is arranged.

23. The method according to any one of claims 20 to 22, characterized in that an air flow is generated which passes through the interior from top to bottom.

24. The method according to claim 23, characterized in that the air flow is evened out by a sieve arranged below the interior.

25. The method according to claim 23 or 24, characterized in that the air flow above the interior is passed through a narrowed fiber inlet opening relative to the interior.

26. Nonwoven fabric, produced by a method according to one of claims 20 to 25, characterized in that the nonwoven fabric is a starting material for the production of tampons and contains trilobal shaped or round viscose fibers or a mixture of both, the fibers having dtex values of 1.7 to 6.7 dtex and a length between 30 and 38 mm and the fleece has a basis weight between 200 and 1000 g / m ² .

27. The fleece according to claim 26, characterized in that the fleece is composed of two or more layers.

28. Nonwoven fabric, produced by means of a method according to one of claims 20 to 25, characterized in that the nonwoven fabric contains flax fibers or hemp fibers or similar natural fibers alone or mixed with synthetic fibers, the natural fibers typically having fiber lengths of 50 mm.

29. Nonwoven according to claim 28, characterized in that the nonwoven has a basis weight between 1200 and 2500 g / m ² and synthetic fibers contains polypropylene or polyester fibers, the dtex values of which are between 1, 7 and 20 and the length of which is between 12 and 38 mm.

30. Nonwoven according to claim 28, characterized in that the nonwoven has a basis weight between 40 and 100 g / m ² and synthetic matrix fibers in the form of polypropylene fibers or polyester fibers, the dtex values of which are between 1, 7 and 20 and whose fiber length is between 12 and 38 mm and contains synthetic binding fibers in the form of bicomponent fibers, whose dtex values are between 1, 7 and 20 and whose fiber length is between 3 and 36 mm.

31. Nonwoven fabric, produced by means of a method according to one of claims 20 to 25, characterized in that the nonwoven fabric contains polyester fibers with dtex values between 6.7 and 10 dtex and a fiber length between 24 and 36 mm and the fibers after forming a Fiber bed with styrene butadiene rubber (SBR = styrene butadiene rubber) or with another binder such as EVA (ethylene vinyl acetate) or an acrylic.

32. Nonwoven according to claim 31, characterized in that the nonwoven is a preliminary product for the manufacture of baby diapers, sanitary napkins, incontinence products or the like and has a basis weight between 20 and 100 g / m ² .

33. Nonwoven fabric, produced by a method according to one of claims 20 to 25, characterized in that the nonwoven fabric is a preliminary product for the production of moist cosmetic skin care wipes and propylene fibers or polyester fibers with dtex values between 1.0 and 3.3 dtex as well as fiber lengths between 24 and 38 mm.

34. Nonwoven according to claim 33, characterized in that the nonwoven contains viscose fibers or loosened wood cellulose pulp fibers (fluff pulp), the mixed with the polypropylene or polyester fibers either as a uniform blend or in layers.

35. Nonwoven according to claim 33 or 34, characterized in that the nonwoven has been water-jet consolidated or felted in another way after the fibers have been deposited.

36. Nonwoven according to one of claims 33 to 35, characterized in that latex is applied to one or both surfaces of the nonwoven.