EP2123826B1 - Method and device for producing a laminar product - Google Patents

Description

The invention relates to a method and an apparatus for producing a surface product.

The prior art discloses a multiplicity of pertinent surface area product solutions.

For example, by the WO 02/13647 A2 a method for producing a surface product known as an adhesive closure part, comprising a plurality of integrally connected to a carrier and symmetrically constructed form elements in the form of entangling means in the manner of each one provided with a head portion stem, in which a moldable material in a forming zone between a pressure tool and a mold is supplied.

In the known method, the opposing boundary walls are at least in a longitudinal section of the respective mold cavity continuously equipped with a convex trajectory, so that a smooth transition between the cross-sectional shapes of the stem and head part is achieved for a Verhakungsmittel the support member, so that it insofar comes to a non-inhibiting demolding process for the surface product from the manufacturing device.

• Auswählen mindestens eines ersten Materials für eine erste Materialschicht,
• Auswählen mindestens eines zweiten Materials für eine zweite Materialschicht,
• Schmelzformen der ersten Schicht mit einer ersten Oberfläche und einer zweiten Oberfläche aus dem ersten Material,
• Schmelzformen der zweiten Schicht mit einer ersten Oberfläche und einer zweiten Oberfläche aus dem zweiten Material,
• Verbinden der ersten Oberflächen der ersten und zweiten Materialschicht, während sich die Schichten im geschmolzenen Zustand befinden, zur Ausbildung einer mehrlagigen Folie als Trägerteil und
• Ausbilden mehrerer Stiele auf mindestens der zweiten Oberfläche der zweiten Materialschicht,
• wobei dieser Formschritt das Formen der mehreren Stiele aus mindestens dem ersten Material und/oder dem zweiten Material und das Verfahren weiterhin den Schritt des Steuerns der Verarbeitungsbedingungen und der Dicke, Viskosität und relativer Größen des ersten und zweiten Materials umfasst, derart, dass das erste Material, das die erste Schicht bildet, in oder durch die auf der zweiten Oberfläche der zweiten Schicht ausgebildeten Stiele hindurch ragt und Teil der Stiele bildet.

By the EP 1 028 639 B1 A method is known for producing a carrier sheet of plastic material having a plurality of stems as sheet product extending from at least one side of the sheet, the method comprising the steps of:

• Selecting at least one first material for a first material layer,
• Selecting at least one second material for a second material layer,
• Melting the first layer having a first surface and a second surface of the first material,
• Melting the second layer with a first surface and a second surface of the second material,
• Bonding the first surfaces of the first and second material layers while the layers are in the molten state to form a multilayer film as a support member and
• Forming a plurality of stems on at least the second surface of the second material layer,
• wherein said forming step comprises forming the plurality of stems from at least one of the first material and the second material, and the method further comprises the step of controlling the processing conditions and the thickness, viscosity, and relative sizes of the first and second materials such that the first material forming the first layer, protruding into or through the stems formed on the second surface of the second layer, and forming part of the stems.

Further, this document discloses a web as a surface product solution prepared by this method. With this known solution, at least one of the two material layers is produced by coextrusion of the plastic material, wherein in a further method step the stem ends are calendered with another forming roll to obtain a mushroom hook closure material as a final product.

With the known methods can be a variety of different embodiments of a Haftverschlussteiles be obtained as area product with preferably mushroom-shaped adhesive closure parts as mold elements on a band-shaped support member, which are characterized in that the respective form or closure element (stem and head) is solid formed of a plastic material , Although the plastic materials used here are recyclable and even at least partially biodegradable, the use of pertinent materials, particularly with regard to packaging technology and with regard to increased environmental compatibility, still leaves something to be desired. There is also a growing scarcity of raw materials on the markets, causing plastic prices to soar so that the end products produced from them are becoming expensive.

Furthermore, in the state of the art surface products include a large number of paper or cardboard box products, which are also used as so-called display packaging to open up the possibility for the modern consumer goods industry to directly place and rearrange a large number of products at the point of sale. In general, the pertinent display packaging is formed in the manner of a display pallet and the like, as usual in other pallet systems transported, but then regularly at the place of installation and sale for the respective installation or sales team a variety of Handling steps is necessary to make the content of the display pallets salable.

To counter this disadvantage is in the WO 2007/059862 A1 Although already a stand part, in particular corrugated cardboard, solid board or the like Material consisting, shown, the individual faces along fold lines folded in a time-saving manner give a quick box or display structure; However, this development requires a high level of experience that not every manufacturer of cardboard or paper products has.

Furthermore, the consumer knows from everyday life and paper surface products such as toilet paper, handkerchiefs, towels, wipes, etc., the sometimes multi-layered modern product requirements satisfy.

From the WO 00/05989 For example, a packaging material is known in which a layer may have wave-shaped or hump-shaped surface areas in order to form an adhesive closure part. The packaging material may be made of cardboard.

Based on this prior art, the present invention seeks to provide a method for producing a surface product available, with which can increase the application possibilities for pertinent surface products in an advantageous, process-reliable and cost-effective manner. The invention is further based on the object to provide a device with which the manufacturing process process technology can be realized safely.

The pertinent objects solves a method according to the feature configuration of claim 1 and a device with the feature configuration of claim 7.

The inventive method is used to produce a surface product, which at least partially cellulosic constituents, in particular of paper or paperboard and has a support member, wherein by means of at least one shaping tool individual fungus-like form elements are formed, which are integral or separate part of the assignable support member and are at least partially formed above this.

Thus, for example, the support member may be constructed of cellulosic components, for example, entirely made of paper, which should be highly absorbent and by means of the shaping tool can be individual mushroom-like form elements as integral part of the support member on this above put on. In that regard, the individual form elements in the form of mushroom-like projections are likewise formed from cellulosic material, in particular from paper material. By the individual form elements, in particular with regard to the enlarged diameter head parts, now on the one hand, an increase in surface area for the support member and on the other allow the mold elements a kind of scratching effect, which improves the Abreinigungsergebnis, especially if the thus constructed surface product as a wipe in the home is used or as toilet paper its intended purpose.

In order to improve the absorbency even further, so far, the carrier part of the mentioned area product is constructed in several layers, with some of the layers may prove to be particularly absorbent and the other part serves mainly the stability of the overall product. Although it is also common in domestic household products to achieve the mentioned surface enlargement with scratching effect by impressing a relief-like structure in the paper material; but the molded, individually protruding mold elements, which otherwise leave the surface of the support member untouched, prove to be the better solution.

The scratching effect can be improved if the carrier part is again made of paper; However, the mold elements as a separate component, for example, consists of cellulose material with plastic parts, applied to the support member made of paper. The cellulose-plastic molded elements For example, in the manner of enlarged drops with widened head diameters, it is possible to spray onto the carrier part, with the spray device then forming the shaping tool. The sprayed or otherwise applied droplets maintain their droplet shape despite the cellulose base due to the surface tension of the plastic material and can be cured and dried on the support part accordingly, for example using a heat source. The paper-like, possibly multi-layered support part then remains absorbent and the applied, on the support part solidified mushroom-like droplets, in turn, increase the scratching effect for improved cleaning of surfaces of any kind.

In a particularly preferred embodiment of the method according to the invention, however, the individual form elements are formed as mushroom-shaped closure elements, so that it is possible using the method according to the invention to produce an adhesive closure part made of paper or paperboard. The adhesive fastener elements can be attached directly to paper or cardboard products such as boxes, possibly in one piece, so that the boxes for receiving a packaged goods can be reliably close without additional closure systems would be necessary, such as adhesive tapes, strapping, package cords and the like. In order to give the mold elements increased rigidity, it is preferably provided to offset the cellulosic suspension from which the mold elements can be produced with a plastic material, for example with a predeterminable percentage of conventional polymer material.

The surface fastener, largely constructed from paper material, proves to be particularly easy to recycle and to biodegrade. Incidentally, it can be produced on an industrial scale, which has a cost effect on its production price. It is surprising to one of ordinary skill in the art that he uses surface-mount fasteners such as Velcro ^® fasteners using cellulosic material can build, that are reliable in use and long lasting usable.

The mushroom-shaped closure elements of an adhesive closure part can be combined with mushroom-shaped closure elements of another adhesive closure part to form a repeatedly openable and closable adhesive closure; but it is also conceivable to connect a conventional loop or loop material of a closure part with the closure part with the hook or mushroom-shaped form elements made of paper. In order to achieve a special security in the closure geometry, it is preferably provided that a thermosetting curable molding compound is applied to the free head side of the respective mold element, which stiffen the paper head in order to ensure a safe Unterhakungsmöglichkeit. The thus produced closure of paper forming elements and paper carrier part builds particularly easy and the cellulose material used can be obtained inexpensively in very large quantities on the world market, which is already no longer the case with some types of plastic.

If it depends on a further reduction in weight, the individual mold elements can also be obtained as a hollow element, d. H. The interior of the stem of the mold element forms a cavity that can be filled again if necessary, for example, with flame-retardant or flame-resistant materials, so as to be able to ensure increased fire safety in safety-related areas. In that regard, the extinguishing agent can be introduced directly into the surface fastener.

Since in the application of the method according to the invention cellulose-containing suspensions are used which are very hydrous; Thus, for example, 1% solids can come to 99% water content, this circumstance contributes to the manufacturing device in so far as the forming tool consists of a forming wire. In this case, the respectively used Siebstruktur also be multi-layered, so that a part of the screen structure predominantly the shape of the form elements is used and the other screen element primarily complies with the drainage task. If preferred stainless steel screens are used, the corrosion has been effectively countered, even if, if appropriate, by further additives of the suspension this should have a certain acid content.

The surface product produced by the method and the device can, as stated above, be used for a multiplicity of applications, the list of which is incomplete. Other applications are conceivable in the field of clothing; but there are also conceivable technical applications, for example in the field of aerospace engineering, rail technology, mechanical engineering, automotive engineering, etc.

Fig. 1

eine schematische Darstellung einer Herstellvorrichtung zum Durchführen des erfindungsgemäßen Verfahrens;

Fig. 2

eine gegenüber der Fig. 1 geänderte Ausführungsform der Herstellvorrichtung;

Fig. 3

in stark vergrößertem Maßstab einzelne Formelemente eines Flächenproduktes, hergestellt mit einer Herstellvorrichtung nach den Fig. 1 und 2; und

Fig. 4 bis 6

einen Teilausschnitt betreffend verschiedene Flächenprodukte auf der Grundlage des Flächenproduktes nach der Fig. 3.

In the following, the solution according to the invention will be explained in more detail with reference to various embodiments according to the drawing. This show in principle and not to scale representation of the

Fig. 1

a schematic representation of a manufacturing apparatus for performing the method according to the invention;

Fig. 2

one opposite the Fig. 1 modified embodiment of the manufacturing device;

Fig. 3

on a greatly enlarged scale individual form elements of a surface product, manufactured with a manufacturing device according to the Fig. 1 and 2 ; and

4 to 6

a partial section concerning different surface products on the basis of the surface product after the Fig. 3 ,

The manufacturing device according to the Fig. 1 shows their basic structure in horizontal manufacturing orientation. Between two roller-shaped guide bodies 10, of which at least one is drivable, extends a band-shaped forming wire 12, which is part of a designated as a whole by 14 forming tool. The forming wire 12 has a plurality of individual mold cavities 16, which pass completely through the forming wire 12 and the respective cavity 16 has seen from the side according to the sectional view of the Fig. 1 the shape of a hyperboloid of revolution. However, other cavity forms are also possible here. The manufacturing device according to the Fig. 1 also has an additional circulating dewatering belt 18 which is arranged in a flat surface with the forming wire 12 between this and the two guide bodies 10. The dewatering belt 18 is provided with a continuous perforation 20, wherein the openings formed in the manner of a fine perforation form far more passages with a smaller cross-sectional area than those formed by the mold cavities 16 of the forming wire 12.

The subdivided in the manner of upper run and lower run bands 12 and 18 have in the plane of a certain width and in the Fig. 1 Cavities 16, which are shown in only one plane, extend as well as the perforation 20 into the plane of the drawing over a predeterminable distance. The thus formed screen belts 12 and 18 may each have several 100 or 1000 through openings on 1 cm ² strip material surface. The better understanding because but are in the presentation after the Fig. 1 the proportions so far not correctly reproduced. In any case, the perforation 20 is designed in such a way that the pulp material essentially remains in the mold cavities 16 and can not escape unintentionally.

The drive direction of the guide body 10 is in the Fig. 1 reproduced with arrows, so that in the selected drive direction, the two Bands 12 and 18, looking in the direction of Fig. 1 seen, move relative to the upper run position from left to right, both bands with the same axial travel speed. Furthermore, the device according to the Fig. 1 an applicator 22, which provided on its underside with individual nozzles, the spray application, allows an even closer presented suspension. Likewise on the upper side of the upper run, a drying device 24 is arranged in the direction of travel of the two belts 12 and 14 behind the application device 22, which by means of hot air or other heat radiation (UV, IR, ultrasound) over a certain drying zone, the drying of the suspension material. On the underlying upper side of the upper run a collecting device 26 is arranged, which captures excess water of the suspension and removes it from the manufacturing device.

Furthermore, cooling devices (not shown) may be present which cool the finished surface product, which may also facilitate demolding to that extent. In addition, a blowing device 28 can be provided on the upper side of the lower run, which helps to demold the surface product to be produced, wherein the pertinent demolding process can be supported by a removal roller 30, the finished fabric produced the manufacturing device of the same for removal and further processing or shipping takes. Furthermore, the production device can still have a calendering roller 32 for a post-forming operation, which will be explained in more detail below.

To obtain the desired surface product, a cellulose-containing suspension is applied via the applicator 22 to the upper side of the upper run of the forming wire 12 and the aqueous suspension or cellulose pulp penetrates into the mold cavities 16 of the forming wire 12. In the pertinent shaping process remains on the top of the upper run of the forming wire 12, a belt-like support member 34 with the individual mold elements 36 are integrally connected. In order to facilitate the entry of the suspension, preferably in the form of cellulose pulp in the mold cavities 16, an auxiliary recording device 38, for example, consisting of two oppositely disposed pressure rollers, which support the described entry with a corresponding contact force and the density of the support member 34 with pretending.

It can be provided here several pressure rollers, which are omitted for simplicity in the illustration. As an alternative or in addition to the mentioned spinning rollers, the auxiliary recording device 38 may also have an air knife arrangement (not shown in more detail) with which the entry is supported to the extent described in the manner of an air curtain and under overpressure. The molding process is driven at such a speed that in any case excess water can escape from the suspension and penetrate the perforation 20 of the dewatering belt 18 in order to be able to be removed from the manufacturing device by the trough-like collecting device 26. The already indicated drying device 24 also serves from the other side to the drying of the pulp to be solidified, which forms the paper structure for the surface product.

If the pulp, in particular in the area of the lower run of the production device dried so far, the band-shaped support member 34 can be deducted from the top of the forming wire 12, preferably using the removal roller 30 and the finished mold elements 36 are pulled out of the assignable mold cavities 16, which by the shown blowing device 28 can still be supported by this compressed air blows through the perforation 20 of the dewatering belt 18, as well as through the mold cavities 16 of the forming wire 12 from the rear region forth. The thus shaped mold elements 36 together with the carrier part 34 have a basically geometric structure, as in Fig. 3 as well as in the Fig. 4 shown. In order to plan headboards accordingly arrive, as in the Fig. 5 shown presses the calendering roller 32 from above on the head-side projections of the front end of each mold element 36, with the result that a flattened head geometry according to the idealized representation of the Fig. 5 established.

As already indicated, the formation of the surface product is a cellulosic suspension in which about 1% solids to 99% water content falls. To form the cellulosic suspension, fibers are preferably used having a diameter between 1 .mu.m and 100 .mu.m, preferably of the order of 10 .mu.m, and the length of the respective pulp fiber should be in the range of 10 .mu.m to 2 mm, preferably about 100 .mu.m. It has proved to be particularly favorable to obtain pulp fibers from vegetable raw materials, wherein preferably pine and spruce as the feedstock result in a long-fiber pulp which can be used particularly well within the framework of the described production device.

However, it has been shown in practice that a pure pulp suspension depending on the application for the finished sheet product as paper product may prove to be too stable, so that the use of plastic materials, such as polymer blends, makes sense, and it has proved to be particularly favorable 10 to 15.5% polymer material in the suspension to use. Further, additives may be added to the cellulosic suspension, such as wet strength agent in the form of melamine resin or in the form of epichlorohydrin resin. In order to help prevent increased adhesion of the cellulose pulp to the forming wire 12, an anti-sticking agent, for example in the form of talcum powder, may be applied to the forming wire 12 with its cavities 16 by suitable means (not shown). Other additives may be provided to eliminate formaldehyde from the pulp suspension or to remove impurities that could hinder the process.

• Ammonium Phosphat (AP),
• Ammonium Polyphosphat (APP),
• Resorcinol bis-Diphenylphosphat (PDP),
• Roter Phosphor (RP),
• Tri-n-butyl Phosphat (TBP),
• Tricresyl Phosphat (TCP) und
• Triphenyl Phosphat (TPP).

It has proved particularly advantageous to use cellulose feedstock on staple fibers of the same length, wherein so-called bicomponent fibers can also be used, each of which has a cellulose core which is surrounded by a polymer shell. The pertinent cellulose input material is freely available on the market, so that will not be discussed in more detail here. As experience has shown that the paper surface product is easily flammable, additional materials can be used in order to have a flame-retardant or active extinguishing medium. Particularly suitable for this purpose are the following groups of substances:

• Ammonium phosphate (AP),
• Ammonium polyphosphate (APP),
• Resorcinol bis-diphenyl phosphate (PDP),
• Red phosphorus (RP),
• Tri-n-butyl phosphate (TBP),
• Tricresyl phosphate (TCP) and
• Triphenyl phosphate (TPP).

As an active extinguishing medium may preferably be provided an extinguishing gas such as nitrogen, wherein as a nitrogen carrier, in particular melamine comes into question but also magnesium hydroxide (MDH). Preferably, it may further be provided that nanoparticles such as silicates or graphite are introduced or applied at least into the carrier part 34, which likewise have very good extinguishing properties and, moreover, can stiffen the paper carrier part 34 if necessary.

It is particularly advantageous, however, to put on the underside of the upper strand of the belts 12 and 18 a vacuum device, not shown, which is arranged, for example, in the region of the collecting device 26, which promotes dewatering of the fiber suspension, and pulp material as long from the individual mold cavities 16 sucks until a hollow stem cross-section (not shown) is created for the single mold element 36, which applies, moreover, with its edge-side material to the respectively assignable mold cavity 16. The hollow stem part produced so far can then be provided with a flame-retardant agent or else serve to introduce another stiffening agent, for example in the form of a polymer-plastic material to be injected. Preferably, however, it is stated that essentially a sheet product consisting of paper or board material as a whole is obtained as a final product which, viewed from the weight side, builds up very easily and can always be used there, where weight reduction is important, for example in the art technical field of aircraft construction, where the use of such flexible surface products would be possible as a cable tie or the like. Also, upholstery fabrics, wall coverings or the like could be safely determined with the indicated paper closure material in lightweight construction.

Temperatures around 60 ° C. have proved favorable as processing temperatures for the aqueous pulp suspension to be applied, as well as a residence time of 10 to 15 min. At a temperature of 70 ° C. for the drying zone by means of the drying device 24. To the finished surface product as little as possible damage, a Teflonauflage for the calendering roll 32 is preferably provided. Furthermore, binder and crosslinking materials, which are not shown in more detail, can be used in order to promote solidification of the pulp material.

If a calender roll 32 as shown in the Fig. 1 is used, can be flat head sides for the mold elements 36 reach as in the Fig. 5 demonstrated. These can then be provided as a starting material from the free head side with a thermosetting molding compound as the respective head part 40, which forms a kind of protection or Verhakungskappe in hemispherical shape. The thermosetting molding compound to this effect can be applied to the free end faces of the mold elements 36 via a conventional applicator, such as spray or doctor device and in the cured state, the head part 40 designed in this way is configured together with the underlying mold element 36 as a mushroom-shaped hooking element, so that in this respect a hookable adhesive closure part is created, that with corresponding elements of another adhesive closure part (not shown) forms a repeatedly openable and closable adhesive closure.

If, however, a structure is maintained, as in the Fig. 3 and 4 is shown as an example, the pertinent solution of a surface product is particularly suitable for use in the fields of tissue paper, toilet paper and wipes. Since the pulp material for the support member 34 may be very thin, is in a preferred embodiment of the surface product according to the representations of the 4 to 6 below the support member 34 to form a multi-layer system, a support layer 42 is present, for example, formed from a thin-walled polymer material or the like. The pertinent support layer 42 may also be elastic, so that when stretched the contrast rigid paper support member 34 can tear between the mold elements 36, with the result that depending on the applied strain the mold elements 36 move away from each other and in a starting position according to the Representations after the 4 to 6 via the support member 34 in turn reach their initial position shown.

Hereinafter, a modified manufacturing apparatus according to the Fig. 2 explained in more detail. In the solution after the Fig. 2 In turn, a roller-shaped drive body 10 is used, which is to rotate in the direction of the arrow shown. On the guide body 10, a forming wire 12 is arranged, which the forming wire 12 according to the solution of the manufacturing device according to the Fig. 1 equivalent. Again, the Formsieb 12 can easily replace a new case of wear, without the guide body 12th would have to change. Also, preferably made of stainless steel forming wires 12 are cleaned off from time to time, so it is advantageous if you can remove them from the guide body 12 without problems. In principle, however, it would also be conceivable to introduce the mold cavities 16 directly into the guide body 10 as part of the same. In the present case, however, the guide body 10 shown is provided along its upper side with a perforation, not shown, over which the dehydration can take place, so that parallels exist in this respect to the perforation 20 of the dewatering belt 18 according to the solution Fig. 1 ,

Also the solution after the Fig. 2 has a collecting device 26 for water, which is preferably formed in the present case as a vacuum device. In the direction of the arrow below, the drying device 24 is arranged, to which in turn the blowing device 28 is connected. The devices 24, 26 and 28 are arranged stationary and the guide body roller 10 rotates together with the forming wire 12 about the pivot axis 44 of the overall device. The solution after the Fig. 2 again has the removal or removal roller 30 and the insertion aid 38 is this time of a circumferential, one-piece band, which is guided around guide rollers 56 and otherwise according to the arrow representation has a drive direction corresponding to the drive direction of the forming screen roller 10, 12.

The band of the insertion aid 38 may preferably be made of a flexible, resilient material; but here is also the use of metal foil materials, such as an aluminum foil or the like possible. The band of the recording auxiliary device 38 can be driven independently or preferably be taken by the friction during the rotational movement of the guide body 10. Furthermore, the solution according to the Fig. 2 a doctor device 48, with which the pulp-containing suspension can be applied to the forming wire 12. The Band-shaped insertion auxiliary device 38 then again helps to form the strip-shaped carrier part 34 to introduce the pulp suspension into the mold cavities 16 of the forming wire 12. The finished surface product, the representation of the Fig. 3 corresponds, is then discharged on the bottom of the manufacturing device. Again, it has proved to be favorable to apply by means of an unspecified applicator talcum on the forming wire 12 with its mold cavities 16. If the removal roller 30 has a cooling section, this can lead to the molded elements 36 shrinking somewhat in the mold cavities 16, which helps to make the removal process considerably easier.

Claims (7)

1. A method for producing a laminar product that has components that at least partially contain cellulose, in particular are made of paper or cardboard, and that has a carrier part (34), there being formed by means of at least one forming tool (14) individual moulded elements (36) which are an integral or separate component of the assignable carrier part (34) and are formed at least partially projecting over the latter, the forming tool (14) being provided with a plurality of mould cavities (16) in which the moulded elements (36) are formed individually by introducing a suspension containing cellulose into the respective cavity (16) such that the respective moulded element (36) is provided, like a mushroom, with a head part with a diameter that is widened with respect to a diameter of the assigned stem part that tapers towards the carrier part (34), at least in the base transition region, and that the respective moulded elements (36) are only removed from the mould cavity (36) when they have at least partially solidified or hardened in the latter due to drying.
2. The method according to Claim 1, characterised in that the carrier part (34) and/or the moulded elements (36) are formed from a suspension that contains cellulose, in particular a cellulose pulp.
3. The method according to Claim 2, characterised in that there are added to the suspension additives such as

   - plastic materials,

   - wet-strengthening agents,

   - binders and cross-linking materials,

   - flame-retardant agents.
4. The method according to any of Claims 1 to 3, characterised in that the respective carrier part (34) of the laminar product is formed from a number of layers.
5. The method according to any of Claims 1 to 4, characterised in that a thermosetting moulding compound is applied to the exposed head side of at least one part of the moulded elements (36) as a head part (40).
6. The method according to any of Claims 1 to 5, characterised in that at least part of the moulded elements (36) is in the form of a hollow body.
7. A device for implementing the method according to any of Claims 1 to 6, the forming tool (14) being formed in the manner of a forming screen (12), the cavities (16) of which form the moulded elements (36), characterised in that in addition to the respective forming screen (12) there are also perforated dewatering devices (18, 20) which adjoin the forming screen (12).

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