WO2004016425A2

WO2004016425A2 - Sealing mat comprising a superabsorbent layer, method for the production thereof, use thereof, superabsorber, and hot melt adhesive

Info

Publication number: WO2004016425A2
Application number: PCT/CH2003/000552
Authority: WO
Inventors: Paul Vogt; Ralf RÖHLEN; Martin Tennie
Original assignee: Paul Vogt; Roehlen Ralf; Martin Tennie
Priority date: 2002-08-15
Filing date: 2003-08-15
Publication date: 2004-02-26
Also published as: WO2004016425A3; EP1534515A2; AU2003249836A1; AU2003249836A8

Abstract

Disclosed is a sealing mat (10) which swells under the influence of a liquid and in which a material (3) that is made of a superabsorber is disposed between two fleece layers (1, 2), said material (3) fixing the fleece layers ( (1, 2) to each other. The highly swelling and light sealing mat can be used for sealing purposes in structural and civil engineering, particularly for building tunnels.

Description

Sealing atte and geomembrane with a superabsorbent layer, process for their production and use thereof

Reference to related applications This application claims the priorities of Swiss patent applications No. 1399/02 of August 15, 2002, No. 1405/02 of August 16, 2002 and No. 769/03 of May 2, 2003, the. The content is hereby fully incorporated by reference.

Technical field

The invention relates to a sealing mat with a swellable material arranged between textile fabrics, in particular nonwoven mat. The invention further relates to a method for producing such a sealing mat and the use thereof. Furthermore, the invention relates to a sealing mat according to the preamble of claim 32 and a method for their production and their use. The invention further relates to a sealing membrane according to claim 40 and its production and use.

DE-A-19521350 or DE-A-19625245 and DE-A-19628493 show a sealing mat in which a water-absorbing substance in powder form is sprinkled into a mechanically strengthened nonwoven or into a fabric or in which the nonwoven or fabric with such

Fabric is soaked. The fleece or fabric layer impregnated in this way is sewn with cover fleece arranged on both sides. The amount of water-absorbing material that can be introduced into the middle fleece or fabric is not very large in this way. Together with plastic sealing sheets on both sides of the sealing mat, it is used in tunnel construction. The sealing function against Penetrating water of such sealing mats is based on the fact that the material absorbs and swells water when water enters through an injury point on the plastic sealing membrane, thus closing the water entry point. EP-A-0278419 shows a sealing mat made of two non-woven layers with an intermediate layer of bentonite, all layers being needled. DE-A-19859728 shows a water-swellable hot melt adhesive. WO 87/03225 shows the layered application of thin bentonite layers by means of repeated application of adhesive to a water-impermeable plastic film.

EP-A-0 588 288 shows the formation of a plastic film which contains a swellable material. DE-A-2649113 shows water barrier plates made of corrugated cardboard with bentonite material embedded in the spaces between them. Water-blocking, swellable material for linear sealing or for sealing joints, cracks and the formation of barrier profiles is e.g. known from the following documents: EP-A-0318615, JP 1066285 (published March 13, 1989), JP 2002180031 (published June 26, 2002), JP 2001303896 (published October 31, 2001), JP 60240779 (published November 29, 1985) ), JP 8157805 (published June 18, 1996) and JP 2206657 (published August 16, 1990). Single-layer or multi-layer geomembranes

Plastic films are known. In construction, specially designed plastic sealing sheets for sealing tunnel vaults are known, these plastic sealing sheets having multiple layers and, in addition to the actual sealing layer, having a signal layer of a different color, by means of which a violation of the sealing sheets is indicated; Such types of waterproofing membranes are generally certified, i.e. approved by governmental or private certification bodies for use in the manufacture of tunnel seals. Presentation of the invention

The invention is based on the object of creating a light, high-density sealing mat. This task is done with the characteristic

Features of claim 1 solved or with the characterizing features of claim 32.

The fact that the swellable material is a super absorber and an adhesive, which is arranged directly between two textile fabrics or on the layer, results in a light sealing mat or sealing membrane with very high swelling capacity and good stability, which is also easy to produce. The layer of superabsorbent and adhesive, preferably a hot melt, can swell and thus seal well and at the same time creates the connection of the material to the textile fabrics that separate the material between itself and partly. also in itself or to the position on which the material is arranged. In a preferred embodiment, the one textile fabric is a fleece and the other textile fabric is a fabric, which fabrics enclose the superabsorber between them and are connected to one another by the adhesive. Water that reaches the sealing mat on the fabric side under pressure can pass through its mesh to the superabsorber, the fabric not distributing the water laterally.

In a preferred embodiment, the fleece layers or mats consist of a continuous fiber fleece, which results in particularly good water entry or water distribution, so that the swellability of the superabsorbent can be used particularly well. Such nonwovens are preferred to staple fiber nonwovens made from very short individual fibers. A fabric made of a chemical fiber, for example made of polyethylene fibers, is preferably used as the fabric. It is furthermore particularly preferred if the weight of the nonwoven is in a range from 80 g / m ² to 200 g / m ² , with good results also being able to be achieved at 50 g / m ² to 300 g / m ² . The superabsorbent is preferably in powder powder. Granular shape arranged between the textile fabrics. Some of it is held mechanically, some is held by the adhesive itself. The proportion of adhesive or hot melt is 10 to 30 percent by weight, preferably 15 to 25 percent by weight and preferably approximately 20 percent by weight, based on the amount of superabsorbent. This results in good adhesion without too much of the superabsorbent being surrounded by hotmelt and thus restricting its water absorption capacity. Different granule sizes of the superabsorbent are preferably used at the same time. In the preferred embodiment with fleece on the one hand and fabric on the other hand, the ratio of super absorber to adhesive is, for example, 60:40. In addition to the superabsorbent, another hydrophilic substance, such as alumina fibers (bentonite), can be provided. However, the proportion of superabsorbent in percent by weight or volume is preferably above 50%, more preferably above 80%. The sealing mat is preferably provided on one side, for example a fabric side, with a removable protective layer, for example a plastic film. Due to its simple construction, the sealing mat can easily be rolled and form a transport unit as a roll, the protective layer being on the outside. Instead of a removable protective layer, a protective layer that can be broken down by water can also be sprayed on, for example.

The sealing mat is preferably designed as a long, sheet-like mat and has longitudinally side edge areas on which the material is exposed on one side, so that adjacent sheets can be glued in the edge area to form an entire mat. In further preferred embodiments of the sealing mat, it is provided on one or both sides with a more or less tight cover permanently attached to one or both textile layers. In the case of covers provided on both sides, these are preferably sewn together from both sides.

The above variants are also preferred for the sealing mat with one layer. The invention is further based on the object of providing a method for producing the sealing mat.

This is achieved by a method with the characterizing features of claims 19 and 38, respectively. By sprinkling superabsorbent powder or superabsorbent granules and hot melt granules, it is easy to form a very uniform mat with well-defined swelling and strength properties. It is only necessary to apply the second non-woven layer and this composite is heated and pressed together, or in the case of the one layer, there is only heating and, if necessary, pressing the applied superabsorbent / adhesive onto the layer. The sealing mat is preferably used in building construction, civil engineering and tunnel construction.

It is particularly preferred if one of the fleece layers or textile surface layers rests directly on the building part to be protected, without the interposition of a film or cover layer. Another object of the invention is to provide an improved sealing membrane, preferably for tunnel construction.

This object is achieved according to claim 40. Because a plastic sealing membrane is provided with a layer of material that swells when water is absorbed, injuries to the plastic sealing membrane when water enters can be caused by the swelling material to be sealed. Since no fleece or fabric layers are provided, but rather the swelling material rests on the plastic sealing membrane, if necessary with thin adhesive and / or adhesive layers or foil layers in between, or without such directly on the plastic sealing membrane, there is no distribution effect due to textile fabric for the penetrating water, but an effect narrowly limited to the point of injury. Furthermore, the plastic sealing membrane can be installed directly without the need to use additional mats.

An embodiment is possible in which a plastic sealing membrane is provided on both sides of the swelling material.

The plastic geomembranes are preferably plastic geomembranes that are constructed at least in two layers with a gasket layer and signal layer and in particular are plastic geomembranes that are certified for tunnel seals.

BRIEF DESCRIPTION OF THE DRAWINGS Exemplary embodiments of the invention are explained in more detail below with reference to the drawings. It shows

Figure 1 shows a first embodiment of a sealing mat;

Figure 2 shows a second exemplary embodiment of a sealing mat;

Figure 2A shows a modification of the example of Figure 2;

Figure 3 shows a third exemplary embodiment of a sealing mat; Figure 4 is a sheet-shaped sealing mat in

View from above; 5 shows a section through the sealing mat of Figure 4 along the line AA;

FIG. 6 schematically shows a view of a surface mining tunnel to explain a first preferred use of the sealing mat,

FIG. 7 schematically shows a view of an underground construction tunnel to explain a further preferred use of the sealing mat,

FIG. 8 shows a three-dimensional representation to explain a use;

FIG. 9 shows a cross-sectional illustration according to FIG. 8;

FIG. 10 shows a further three-dimensional representation of a use; Figure 11 is a cross-sectional view according to

Figure 10;

Figure 12 shows an embodiment of a sealing mat with a layer;

FIG. 13 shows a side view of a first embodiment of a sealing membrane;

FIG. 14 shows a side view of a second embodiment of a sealing membrane;

FIG. 15 shows the edge areas of two sealing sheets which are designed for partial overlap; FIG. 16 schematically shows a view of a surface mining tunnel to explain a preferred use of the sealing membrane; and

FIG. 17 schematically shows a view of an underground construction tunnel to explain a preferred use of the sealing membrane.

BEST WAYS OF IMPLEMENTING THE INVENTION FIG. 1 shows a first preferred example of a sealing mat 10. This has a first

Layer-forming textile fabric 1, which is preferably a nonwoven layer, which hereinafter also referred to as the backing layer. An upper layer 2 in the drawing also consists of a textile fabric, for example also made of nonwoven, and is also referred to below as a cover layer. Between the two flat structures or layers 1 and 2 and connecting them, there is a super absorber and an adhesive, which together form the material 3. Where we talk about nonwovens in the following, we are basically talking about a flexible, porous and in particular water-permeable textile fabric in the sense of a so-called nonwoven textile fabric, which is a fleece or a felt and not a woven or knitted fabric or knitted fabric. The term textile fabrics encompasses such fabrics, knitted fabrics or knitted fabrics and textile composites. The layers 1, 2 preferably consist of a fleece made of polypropylene fibers. It is further preferred in this example and also in the following examples if the nonwoven is formed from continuous fibers and not from short staple fibers. The nonwovens can have been produced in any known manner.

Also preferred is an embodiment in which one textile fabric 1 is formed by a fleece and the other textile fabric 2 is formed by a fabric. A synthetic fiber fabric is preferred. A fabric with a water permeability of greater than 20 l / m ^ s, preferably greater than 50 l / m ^ s and preferably greater than 100 l / m ^ s, is used as the preferred fabric. The opening or optical mesh size of the fabric is preferably larger than 0.30 mm and preferably larger than 0.60 mm. Such fabrics allow good access of the water to the swellable mixture of superabsorbent granulate and adhesive and do not conduct the water laterally, i.e. in the plane of the fabric, or only slightly, which is only effective for the sealing of the building in the area of the leak. O

same swelling is advantageous. Suitable fabrics consist, for example, of multifilament or ribbon yarns and, for example, of high-density polyethylene (PEHD) or polypropylene (PP) for the transverse direction and, for example, of PEHD monofilament yarns for the longitudinal direction. Commercially available fabrics with such a structure are, for example, type C 50.002 or D 00.006 from Huesker Synthetic GmbH, Germany. It is also possible to use fabrics for both layers 1 and 2. As far as this example and the following examples refer to superabsorbents, it means known superabsorbent polymers which are water-insoluble, hydrophilic, crosslinked polymers which swell and form Hydrogels can absorb and store large amounts of aqueous liquid. Such superabsorbers do not release the absorbed liquid even under pressure. Depending on the type of liquid, the absorption capacity for liquid can be 30 to 500 times the volume of the superabsorbent. These substances are generally known and commercially available. For the example of FIG. 1 and the further examples, commercially available superabsorbers from Degussa Stockhausen GmbH and Co. KG, Krefeld, Germany are used, for example of the type Z 1099 or Cabloc CT. In addition to such superabsorbent polymers, a certain proportion of mineral swellable substances can also be used in the material layer 3, for example swellable alumina (bentonite). The material 3 also contains an adhesive which holds the three layers together or connects the layers 1 and 2 together with the layer 3. Instead of a conventional adhesive, a foamed plastic can also be used as an adhesive or connecting means for the layers. The adhesive added to the superabsorbent is preferably a commercially available hotmelt adhesive. Such adhesives are well known and can also be used in a foamed form with the addition of gas. preferably, an adhesive with a low melting temperature in the range of approx. 80 to approx. 100 ° C is used. The use of an adhesive that melts at low temperatures keeps the distortion of the textile fabrics 1, 2, in particular the nonwoven mats and fabrics, as low as possible in the manufacture of the mat 10. The connection of the two textile fabrics 1 and 2 can also be reinforced by additional sewing or stapling, if this is desired. A seamless or stapling-free connection and thus a connection only by gluing is preferred in the example shown in order to enable the best possible swelling.

The nonwoven layers have a thickness of less than one millimeter to a few millimeters or up to 1.5 cm and can have the same or different thicknesses 3 on both sides of the material. The layer thicknesses shown in the drawings are only to be understood schematically and to explain the structure in all the figures and are not shown in true size and not to scale. The weight per unit area of the nonwoven layers is preferably 50 to 300 g / m ² , particularly preferably 80 to 200 g / m ² . The weight per unit area of the fabric which preferably forms an outer layer is, for example, 150 g / m ² or, for example, 210 g / m ² . The weight per unit area of layer 3 is preferably 100 to 600 g per m ² , this including a hot melt adhesive of 10 to 30 percent by weight, preferably 15 to 25 percent by weight and in particular approximately 20 percent by weight. This results in a good cohesion of the sealing mat without substantial amounts of the superabsorbent being completely surrounded by the hot melt and thus losing all or part of its ability to swell.

The superabsorbent is preferably used as powder or granulate, depending on the grain size. A fine powder or granulate results in very rapid swelling when in contact with water, but less water ability. A coarse powder or granulate results in slower swelling but more water absorption. It is preferred if different powders or granule sizes of the superabsorbent are used simultaneously in layer 3. Possible granule sizes are, for example, from 200 μ to 2 mm in diameter. It is also possible to use only one uniform size (within the manufacturing tolerance).

The production of the sealing mat shown is simple and inexpensive, in that the nonwoven layer 1 is sprinkled with a mixture of superabsorber as homogeneous as possible, at most in different granule sizes, and adhesive, preferably from hot melt, preferably also in granule form, the spreading preferably being done by machine takes place in order to achieve the most uniform possible distribution of superabsorbent and adhesive on the carrier layer. Thereafter, the cover layer 2, in particular as a fabric, is applied to the carrier layer 1 sprinkled with the material 3 and the entire mat 10 is treated by compression, for example by means of rollers and, in the case of hot melt adhesive, heating by heating means in such a way that the hot melt adhesive melts and then cools down again, which leads to a connection of the layers. The mat is preferably produced in webs that are wide and many meters long and rolled up into a roll for transport. It is preferred if, on one side (or also on both sides) of the mat, a removable plastic film is possibly applied to the nonwoven layer and especially to the fabric layer as a protective layer for transport and until the mat is used. Production in a different way is also possible, for example by first applying the superabsorbent to the backing layer, and then punctually or in strips or in a grid-like manner by spraying on an adhesive, after which the covering layer 2 is placed on and pressed between the rollers. follows. In this case too, a non-permanent protective layer or protective layers can be applied on the outside. For these it is also possible for a protective layer to be sprayed on, in which case it is designed in such a way that it can be degraded by the action of water. It is also possible with all examples that, in the case of a hot melt adhesive, this also as water. swellable adhesive is designed which also contains superabsorbent particles in itself. Such water-swellable hot melt adhesives are known. All substances used should be toxicologically and ecotoxicologically safe for groundwater and drinking water.

FIG. 4 and FIG. 5 show a preferred embodiment of the sheet-like sealing mat, the same reference numbers as previously used being the same

Designate parts. FIG. 4 shows a top view of the top layer 2, it being evident that the top layer 2 and the top layer 1 are laterally offset by a certain amount, for example a few centimeters, so that the layer 3 made of superabsorbent and adhesive at the edges the web is exposed once on the carrier layer and once on the cover layer. FIG. 5 shows this correspondingly in section along the line AA from FIG. 4. Of course, as in the other examples, the layer thicknesses have not been chosen to scale for better illustration in the drawing. FIG. 5 shows how a large-area sealing mat can be formed when such sealing mat sheets are placed next to one another. When producing with superabsorbent granulate and hot melt adhesive, a material structure is formed in the exposed edge areas of the carrier layer 1 of the sealing mat web, which consists of super absorber granulate particles held by the hot melt that has already been melted. If such sealing mat sheets are placed next to one another, the hot melt can be melted again by the action of heat in the overlapping edge area, which binding of the different webs results. At most, a larger amount of hot melt and / or super absorber can be provided in the edge area during production. A superabsorbent / hotmelt mixture can also be applied to the free edge area of the cover layer 2 (on the right in FIGS. 4 and 5) in a separate production step.

FIG. 2 shows a further embodiment of a sealing mat 11, which can be constructed with the layers 1 to 3 in the same way as explained in all previous examples. In addition, at least one, usually 2-layer, plastic sealing membrane (KDB) 4 is now provided on one side, which is, for example, a KDB certified for tunnel construction, which is permanently mechanically, by gluing and / or by welding with the one fleece layer (on both sides Fleeces), but in the example shown is connected to layer 2, which is preferably a fabric layer. The swellable sealing mat can be laminated directly onto the plastic sealing membrane at the manufacturer of the plastic sealing membrane. FIG. 2A shows such a sealing mat 36, in which a plastic sealing sheet 34, 35 is provided on both sides of the textile fabrics 31, 32, which accommodate the swelling and connecting layers 33, 32, and each has a corresponding one Layer 32 or 31 is connected. This combination can be used as a flexible seal with a swellable, water-proof property for pressurized water maintenance in civil engineering. The single or multi-layer plastic sealing membrane is on the water-containing side and usually keeps the water away from the building. If the sealing membrane 4 is damaged, the sealing is added by the swelling of the sealing mat, which will be explained in more detail using an example. The plastic sealing membrane KDB can in turn be laminated on its side facing away from layer 1 or 2 with a textile fabric be, for example with a fleece. Instead of the KDB, another plastic film can also be provided.

FIG. 3 shows a further embodiment, the layers 1 to 3 again being implemented in the same way as already described. A more or less liquid-permeable cover 5 or 6 is now arranged on both sides of the sealing mat formed in this way and these foils are preferably connected to one another through the sealing mat by a sewing 7. The result is the sealing mat 12. In this case, it can be used as a self-supporting sealing element, which does not have to be used in conjunction with a separate plastic sealing membrane. It results in a construction that is stable in itself and can withstand the swelling pressure that builds up, e.g. for use in earthworks, landfills, ponds etc.

FIG. 6 now shows, on the one hand, to explain the function of the sealing mat and, on the other hand, as a preferred example of use, a vault 14 of a surface tunnel. Earth layers (not shown) are arranged above this vault and the vault is to be protected against the ingress of water from the outside in the direction of arrow B. For this purpose, webs of a sealing mat according to the invention, for example the sealing mat 10 from FIG. 1 or at most 11 from FIG. 2, are now rolled out over the vault and connected, for example according to FIGS. 4 and 5, to form an uninterrupted sealing mat over the entire vault. It is preferred that a nonwoven layer 1 rests directly on the concrete surface of the vault 14. A plastic sealing sheet 15, which is designed in a known manner, is then applied over the sealing mat 10. For this purpose, plastic sealing sheets are applied to the vault in an overlapping manner next to one another and welded to form a gapless plastic envelope. At most, the plastic sealing membrane of FIG. 2 or of FIG. 2A can function as the casing 15 take over or be present in addition to this. The figure now shows schematically that the casing 15 is damaged, for example by a reinforcing iron 17 of the tunnel arch 14, which pierces the sealing mat 10 and the casing 15. In this case, water can penetrate through the casing 15 along the reinforcing iron 17. The water hits the sealing mat 10 and can easily penetrate its layer 2 in all directions if the layer 2 is a non-woven layer. As a result, the superabsorbent comes into contact with the aqueous liquid and begins to swell strongly wherever this is the case. Since the mat 10 is exposed to pressure between the tunnel vault 14 and the layers of earth lying above the casing 15, the swelling superabsorber also creates a strong pressure on the leakage in the reinforcing iron 17. In a preferred embodiment, the layer 2 is a fabric that the water does not conduct laterally and contributes to a more selective sealing than a fleece. This leak is permanently sealed in both ways, since the superabsorbent retains the water it absorbs and thus its swollen shape. Since the lower textile composite layer, for example the nonwoven layer lies directly on the concrete of the vault 14, any water which has penetrated the sealing mat and has reached the vault and is run along by the nonwoven and comes back into contact with the superabsorber. which causes a corresponding swelling. This results in a corresponding sealing function at all points where there is water. This is not possible in prior art uses, where there is another plastic film between the structure to be protected and the sealing mat, since the water can then flow between the plastic film and the sealing mat on the building, which is preferred by the present one Use with a directly lying sealing mat is prevented. Figure 7 shows another example of use in the underground construction of a tunnel vault. With 20 the profile of the eruption in the rock is designated and with 21 a shotcrete layer that has been applied to the rock. In turn, a plastic cover 15 in the form of welded plastic sheets is applied to this shotcrete layer. Thereafter, in the preferred use, a sealing mat according to the invention, in particular one according to the example from FIG. 1, optionally one according to FIG. 2, is applied to the plastic sleeve 15. The fastening of the sealing mat 10 to the plastic sleeve can be done in any known manner Way. Here too, it is preferred to apply the sealing mat in strips, with overlapping edge regions, as shown in FIGS. 4 and 5. This is followed by concreting the inner tunnel shell 24, which is concreted essentially adjacent to the sealing mat, so that it lies practically directly on the outer surface of the concrete structure 24. If there are voids which are undesired, they can be compensated or filled with an additional injection of a hardening material 22 which is introduced between the structure 24 and the sealing mat 10 and / or between the shotcrete 21 and the casing 15. Here, too, water which enters in the direction of arrow B is eliminated in the event of a leak in the plastic casing 15, for example, again as a result of a protruding reinforcing bar 17, in that the water which passes through the plastic casing 15 hits the sealing mat 10, which is what strong swelling or the strong pressure exerted on the leak, which prevents further water inflow.

FIGS. 8 and 9 show in a diagrammatic representation or in a sectional representation a preferred use of a sealing mat according to the invention or at most a sealing membrane according to the invention. At 20 is in the diagram the tunnel excavation of an underground construction tunnel is shown in FIG. Tubbing elements 50 are arranged in this outbreak in a known manner. In this exemplary embodiment of the invention, a seal is now applied to the inside of the tunnel segments. After this sealing, the inner shell of the tunnel is formed in a known manner, which is not shown. In FIG. 8, various stages of the application of the seal to the inside of the tubbing are shown in order to better explain the structure. In a manner known per se, the total area is divided into individual fields, for which purpose partition profiles 51 are used. In the preferred use, a plastic sealing sheet, which is usually a certified plastic sheeting, is first applied to the inside of the segments as an outer layer. This can be seen in FIG. 8 in the foremost field by the plastic sealing membrane 52, which is only partially shown. FIG. 9 shows that the plastic sealing sheet, which is, for example, a 2 mm thick two-layer sealing sheet, is further provided with a laminated nonwoven layer 53, which points towards the inner tubbing surface. Such plastic geomembranes are known and commercially available. The fleece 53 is fastened to the concrete surface of the segments, for example by means of adhesive, which is shown in FIG. 9 by means of the adhesive beads 54. The adhesive is, for example, a hot melt adhesive. The sealing profiles 51 are glued or welded onto the surface of the plastic sealing membrane 52, as can be seen in FIG. 9, in which two manual weld seams 55 are shown. Corresponding partition profiles made of plastic are known. About the plastic Dic tungsbahn 52, the water-blocking sealing mat 57 is now arranged. For this purpose, assembly gluing can be carried out with an adhesive, which is indicated by the adhesive beads 63. Again, it can be a hot melt adhesive. According to one of the exemplary embodiments, the sealing mat 57 is present invention, in the simplest form according to the example of Figure 1. A correspondingly covered field can be seen in Figure 8. A further plastic sealing membrane 60 is now preferably arranged above the sealing mat 57, which in turn can be a certified sealing membrane, for example 2 mm thick. Their attachment to the sealing mat can in turn be done by gluing, which is indicated by the adhesive beads 61, for example a hot melt adhesive. The individual plastic sealing sheets 52 are sealed or welded to one another, which can be seen, for example, at the seams 59. The sealing membrane 60 is glued or welded to the partition profiles 51, which is indicated by the seams 62 in FIG. 9. The finished sealed fields in FIG. 8 are the two fields at the rear in the drawing, in which the plastic sealing membrane 60 can be seen as the surface. Of course, modifications to the use shown can be made. Thus, instead of the separate plastic sealing sheet and sealing mat, a sealing mat and plastic sealing sheet connected during manufacture can be used, as has been described above with the aid of examples. It is also possible to use sealing sheets according to the invention in which the superabsorber is arranged directly between two plastic sealing sheets, as explained below.

FIGS. 10 and 11 show the procedure in a preferred use for sealing opencast mines in a correspondingly diagrammatic and also cut representation. A single-layer, pressurized water-retaining plastic seal with the built-in water-blocking system according to the present invention is shown. The individual elements of the tunnel vault made of constructional concrete 65 can be seen in FIG. 10. A sealing mat 66 according to one of the exemplary embodiments of the invention is applied to this. It can again for gluing or just hanging up. Bulkhead profiles 67 in turn serve to form individual sectors or fields. A plastic sealing membrane 68 is arranged over the sealing mat, for example glued or even just put on, the individual sealing membranes being connected to one another (double seam 69) or to the partition profile (seams 70). In a known manner, an edge closure band 71 can be provided on the underside. Of course, it is also possible here to work with various embodiments of the sealing mat with a plastic sealing sheet, if any, already attached thereto, or to work with the sealing sheet according to the invention.

FIG. 12 shows a sealing mat 30, which has a layer made of a textile fabric 25, and a layer 26 arranged thereon on one side, which is formed by a superabsorbent with an adhesive. The adhesive forms the attachment of the super absorber to the layer .25. In its simplest form, the sealing mat consists only of this one layer 25 and the one-sided coating 26. In further embodiments, which are shown to the left of the dash-dotted line C, a second layer 27 of the mixture of superabsorbent and adhesive can be on the other surface of the Layer 25 may be provided. In further embodiments, a cover 28 can first be provided over the superabsorbent layer 26. This cover can also consist of a textile material and be more or less permeable to liquids. At most, a film or a plastic sealing membrane can also be provided as a cover 28, which is liquid-tight. A further cover 29 can be provided directly on the other side of the layer 25 or in the case of a further layer 27 above this layer 27, as shown in FIG. 8. The same applies to the cover 29 as stated for the cover 28. The formation of the layer 25 is preferably carried out in the same way as carried out on the basis of the textile fabrics of the preceding examples. All variants of these layers can also be used for the layer 25 as far as possible. In particular, the layer 25 also preferably consists of a nonwoven, in particular an endless fiber nonwoven, or a woven fabric. All the previous information on the layer made of superabsorbent and adhesive and possibly bentonite can also be provided in the sealing mat of FIG. 12. The adhesive is preferably a hot-melt adhesive and the superabsorber can also be one of the preferred types indicated. The layer 26 is again formed by sprinkling powder or granules of the specified sizes and preferably different sizes simultaneously. The superabsorber is attached to the layer 25 by melting and allowing the hot melt to solidify. The hot melt adhesive can be applied simultaneously with the super absorber or before it is applied. Other adhesives can also be used, as described in the previous sealing mats. The use of the sealing mat 30 can in principle be carried out in the same way as has been explained for the sealing mats 10 and 11. In this case, for example, the layer 25 rests on the structure and the layer 26 bears against the plastic shell 15. This is preferred. A reverse arrangement remains possible. The introduction is also clear for the variant with the additional layer 27, in which case a layer of superabsorber is applied to both the shell 15 and the structure.

FIG. 13 shows a first embodiment of a sealing membrane according to a further aspect of the invention in a side view. The layer thicknesses shown are also not shown in true size and not to scale, but only schematically for explanation. construction. This also applies to the other figures.

The sealing membrane 35 has a carrier layer which is formed by a commercially available plastic sealing membrane 31. This is preferably a multi-layer sealing membrane and, in addition to the actual sealing layer 32, has a signal layer 33 which differs in color. The thickness of the plastic sealing membrane can e.g. 2 mm to 4 mm. Such plastic geomembranes can be certified for use in tunnel construction. A plastic sealing membrane that can be used here is e.g. Commercial plastic sealing sheets from Sarna AG or Sika AG or Agru GmbH. Such plastic sealing membranes can also be used in the examples according to FIGS. 1 to 12 if the term is used to refer to plastic sealing membranes. A layer 34 is arranged lying on the plastic sealing membrane 31 and connected to it, which experiences a strong swelling when water is absorbed. Layer 4 can in particular contain or consist of a so-called super absorber. As far as this example and the following examples refer to superabsorbents, e.g. known superabsorbent polymers are meant, which are water-insoluble, hydrophilic, crosslinked polymers which can absorb and store large amounts of aqueous liquid with the swelling and formation of hydrogels. Such superabsorbers do not release the absorbed liquid even under pressure. Depending on the type of liquid, the absorption capacity for liquid can be 30 times to 500 times the own volume of the superabsorbent. These substances are generally known and commercially available. For the example of Figure 13 and the other examples, e.g. commercially available superabsorbents from Degussa

Stockhausen GmbH and Co. KG, Krefeld, Germany, used for example of the type Z 1099 or Cabloc CT. In addition to such superabsorbent polymers, a certain proportion of mineral swellable substances can also be used in the material layer 34, for example swellable alumina (bentonite). The layer 34 further preferably contains an adhesive which ensures the formation of a sufficiently solid layer 34 and its adhesion to the plastic sealing membrane. The adhesive added to the superabsorbent is preferably a commercially available hotmelt adhesive. Such adhesives are well known. An adhesive with a low melting temperature in the range from approximately 80 to approximately 100 ° C. is preferably used. The use of an adhesive that melts at low temperatures keeps the distortion of the plastic sealing membrane as low as possible during the production of the sealing membrane. The use of other adhesives is also possible. The layer 34 can also consist of a plastic, preferably a foamed plastic, for example of the same type as the plastic sealing membrane, the plastic forming the layer 34 together with the superabsorbent material.

The weight per unit area of the layer 34 is, for example, 100 to 600 g per m ² , this including an amount of adhesive or plastic, in particular a hot melt adhesive close to 10 to 40 percent by weight, preferably 20 to 30 percent by weight and in particular approximately 25 percent by weight. This results in a good cohesion of the layer 34 without the substantial amounts of the superabsorbent being completely surrounded by the hot melt and thus losing all or part of its ability to swell.

The superabsorbent is preferably used as a powder or granulate, depending on the grain size. A fine powder or granulate results in very rapid swelling when in contact with water, but less water storage capacity. A coarse powder or granulate results in slower swelling but more water absorption. It is preferred if different powders or granules sizes of the superabsorbent are used simultaneously in layer 33. Possible granule sizes are, for example, from 200 μ to 2 mm in diameter. It is also possible to use only one uniform size (within the manufacturing tolerance).

The sealing membrane shown is simple and inexpensive to produce, for example by sprinkling a mixture of superabsorber, possibly in different granule sizes, and hotmelt, preferably also in granule form, onto the plastic sealing membrane 31, the scattering preferably being done mechanically, in order to achieve the most uniform possible distribution of superabsorbent and adhesive on the carrier layer. The sealing membrane is then treated by heating by means of heating means in such a way that the hot-melt adhesive melts and then cools down again, which leads to a connection of the layers. The geomembrane is preferably produced in webs many meters long and rolled up into a roll for transport. It is preferred if a removable plastic film is applied to the side of the swellable material as a protective layer for transport and until the web is used. At most, this protective layer can remain on the sealing membrane when it is used. It is also possible that an adhesive is first applied to the plastic sealing membrane, for example also as a double-sided adhesive film, on which the superabsorber is then placed. This can also be applied in the form of a film or in a layer that is stable in itself and, if need be, adhere sufficiently to the plastic sealing membrane or be laminated onto it without the use of adhesive. If need be, between the plastic sealing membrane 31 and the layer 34 made of or with the superabsorbent, adhesion promoter or adhesion-promoting foils or layers can be provided. The superabsorbent material can also be used together with a foamed, plastic or an adhesive, for example a hot melt adhesive, are extruded onto the plastic sealing membrane.

In all examples, it is possible that in the case of a plastic or an adhesive, in particular a hot-melt adhesive, it is also designed as a water-swellable substance which likewise contains superabsorbent particles. Such water-swellable hot melt adhesives are known. All substances used should be toxicologically and ecotoxicologically safe for groundwater and drinking water.

FIG. 14 shows an exemplary embodiment in which a second plastic sealing membrane 41 with the layers 42 and 43 is applied to the swellable layer 34. A sealing membrane 36 is thus formed, which is formed on both sides by a plastic sealing membrane and contains the swellable material between these membranes. For the type of plastic sealing membrane 41, 42, 43 and its connection to layer 34, reference is made to the information given, for example, in FIG. 13. The additional plastic sealing membrane 41 is also connected to the layer 34, which is done, for example, by applying the plastic sealing membrane 41 to the still heated layer 34 when using the hot-melt adhesive. The layer 34 connects the plastic sealing sheets 31 and 41 to one another. These could also be designed in such a way that they have mutually pointing fastening means for mechanical fastening to one another. Such a mechanical fastening can be provided in addition to the connection through layer 34 or instead of the connection through layer 34; in the latter case, this can only consist of superabsorbents without adhesive properties or without the addition of an adhesive. Instead of the second web 41, a fabric or a fleece can be provided, for example in an embodiment explained above. FIG. 15 shows the design of (only partially shown) sealing sheets according to FIG. 14 with edges which permit the partial overlapping of adjacent sealing sheets on the edge, so that the sealing sheets can form a uniform surface when they are adjacent to one another. The same reference numerals as in FIG. 14 denote the same elements. The sealing sheets can be connected to one another in a known manner, for example welded. FIG. 16 now shows, on the one hand, to explain the function of the sealing membrane and, on the other hand, as a preferred example of use, a vault 14 of a surface mining tunnel. Earth layers (not shown) are arranged above this vault and the vault is to be protected against the ingress of water from the outside, in the direction of arrow B. For this purpose, sheets of a sealing sheet according to the invention, for example the sealing sheet 35 from FIG. 13 or 36 from FIG. 14, are now rolled out over the vault and, for example according to FIG. 15, connected to form an uninterrupted sealing surface over the entire vault. FIG. 16 shows schematically how the sealing membrane 35 from FIG. 13 with the layer 34 (possibly covered with the aforementioned protective layer) lies on the outside of the vault. The plastic sealing membrane 31 forms a shell. Of course, there may be further layers applied to the arch between the outside of the arch and the layer 34 of the sealing membrane. The figure now shows schematically that the sealing membrane 35 is damaged, for example by a reinforcing iron 47 in the tunnel arch 44, which pierces the sealing membrane. In this case, water can enter the plastic sealing membrane 31 along the reinforcing iron 47. The water strikes the layer 34. As a result, the superabsorbent comes into contact with the aqueous liquid and begins to swell strongly wherever this is the case. Since the sealing membrane between the tunnel vault 44 and is exposed to a pressure above the layers of earth, the swelling superabsorber also creates a strong pressure on the leak at the reinforcing iron 47. In this way, this leak is permanently sealed, since the superabsorber retains the absorbed water and thus its swollen form. If the layer 34 rests directly on the arch 44, any water which has entered the sealing membrane and has reached the tunnel arch is also absorbed by the superabsorber lying directly on the structure. This results in a corresponding sealing function at all points where there is water.

FIG. 17 shows a further example of use in the underground construction of a tunnel vault, a sealing membrane 36 according to FIG. 14 now being used as an example; of course a sealing membrane according to FIG. 13 could also be used here. Only the plastic sealing sheets 31 and 41 are shown, without the layer 34. 20 denotes the profile of the eruption in the rock and 21 a shotcrete layer which has been applied to the rock. A sealing surface in the form of welded sheets 36 is applied to this shotcrete layer in a known manner, for example by gluing. A sheet-by-sheet application of the sealing sheets with overlapping edge regions, as shown in FIG. 15, is preferred. The inner tunnel shell 54 is then concreted, whereby it is concreted in contact with the sealing surface, so that it lies directly against the outer surface of the concrete structure 24. If there are cavities which are undesired, they can be compensated or filled with an additional injection of a hardening material 52 which is introduced between the structure 54 and the plastic sealing membrane 31 and / or between shotcrete 21 and membrane 41. Here, too, water that enters in the direction of arrow B is used in the event of a leak. tungsbahn 36, for example again due to a protruding reinforcing rod 47, remedied by the fact that the water that passes through the plastic sealing membrane 41 hits the layer 34, which causes its strong swelling or the strong pressure exerted on the leak, which causes a prevents further water inflow.

The sealing sheet according to the invention can also be used in the examples of use in FIGS. 8, 9, 10, 11 and can replace the two plastic sealing sheets with the sealing mat in between as one sheet.

The aqueous liquid-absorbent polymer to be used according to the invention has an advantageous combination of properties of high retention, high absorption under pressure and low permeability.

It is obtained by polymerizing ethylenically unsaturated monomers bearing acid groups, for example from acrylic acid, methacrylic acid, vinylacetic acid, maleic acid, 2-acrylamido-2-methylpropanesulfonic acid, vinylsulfonic acid, (meth) allylsulfonic acid or mixtures thereof in the presence of crosslinking agents. Acrylic acid is preferably used as the ethylenically unsaturated monomer carrying acid groups. At least 50 mol%, preferably 70 to 95 mol%, of the acidic monomers are neutralized and are then present, for example, as the sodium, potassium or ammonium salt or mixtures thereof.

Optionally, the polymers to be used according to the invention can contain up to 10% by weight of further comonomers which can be copolymerized with the monomers bearing acid groups in order to modify the properties. Such comonomers can be, for example, (meth) acrylamide, (meth) acrylonitrile, vinyl pyrrolidone, vinyl acetamide, hydroxyethyl acrylate, alkylaminoalkyl (meth) acrylates, alkylaminopropylacrylamides, acrylamidopropyltrimethylammonium chloride or mixtures thereof. Crosslinkers are preferably used in the form of monomers containing at least two ethylenically unsaturated double bonds. The crosslinker content is 0.1 to 5% by weight, based on the monomers used. Superabsorbent polymers to be used according to the invention fulfill certain properties with regard to absorption and absorption under pressure. In an advantageous embodiment, the superabsorbent polymers have a teabag retention of greater than 30 g / g, preferably greater than 35 g / g, an absorption of greater than 30 g / g, preferably greater than 40 g / g, and an absorption, measured under one Pressure of 21 g / cm ² , greater than 15 g / g, preferably greater than 20 g / g for 0.9% saline. For the determination of the teabag retention values and the absorption under pressure, reference is made to WO 92/00108 (page 11). The absorption values are determined in accordance with the "tea bag retention values" method described there, although, after swelling in the saline solution, the tea bag is not thrown off. The superabsorbers to be used according to the invention, after swelling through contact with water, have no or only a very low permeability for the following Water on.

Particularly advantageous properties are achieved with superabsorbers whose particle sizes are in a range from 60 to 500 μm, particularly preferably in a range from 150 to 350 μm.

The adhesives to be used according to the invention are preferably selected from the hotmelts. Products based on polyamides, polyesters, polyurethanes and copolymeric ethylene vinyl alcohols, for example, are used as hot melts, polyamides being used with preference. Polyamides are easy to fill with the superabsorbent polymers and can be adjusted to the required flexibility by blending with the ethylene vinyl alcohols. In a preferred embodiment, a polya- mid / ethylene vinyl alcohol mixture with a weight fraction of the copolymeric ethylene vinyl alcohol of 15 to 45% by weight and particularly preferably 20 to 35% by weight. The hot melts can be adjusted to certain melting points using additives that are customary in the art. Hot melts with a melting range of 90 to 150 ° C., particularly preferably 100 to 140 ° C., are preferably used in the process according to the invention.

Claims

claims

1. sealing mat (10; 11; 12; 36), comprising a swellable material (3) arranged between textile fabrics (1, 2), the swellable material (3) comprising a superabsorbent and an adhesive, in particular a hot melt adhesive , and the textile fabrics (1, 2) are fastened together by the swellable material.

2. Sealing mat (10; 11; 12) according to claim 1, characterized in that at least one of the textile fabrics (1, 2) is formed from a textile composite and in particular both textile fabrics are formed from a textile composite.

3. Sealing mat according to claim 2, characterized in that the textile composite f is a fleece and in particular is a continuous fiber fleece.

4. Sealing mat according to one of claims 1 to 3, characterized in that at least one of the textile fabrics (1, 2) is a woven or knitted fabric or knitted fabric.

5. Sealing mat according to claim 4, characterized in that the textile fabric consists of chemical fiber and in particular is a woven fabric made of polyethylene.

6. Sealing mat according to claim 1, characterized in that the one textile fabric (1, 2) is a textile composite, in particular a nonwoven and the other textile fabric (1, 2) is a fabric.

7. sealing mat (10; 11; 12) according to any one of claims 1 to 6, characterized in that at least one of the textile composite layers, in particular a non-woven layer, a weight of 50 to 300 g / m ² , in particular from 80 to 200 g / m ² .

8. sealing mat (10; 11; 12) according to any one of the preceding claims, characterized in that the Superabsorbent in the form of granules is present between the textile fabrics (1, 2) attached to one another by the adhesive.

9. sealing mat (10; 11; 12) according to any one of the preceding claims, characterized in that the superabsorbent is present in the form of granules in sizes between fine granules to coarse granules in the mat, in particular that two or more different granule sizes are present. 10. Sealing mat (10; 11; 12) according to one of the preceding claims, characterized in that the amount of adhesive, in particular the amount of hot melt adhesive,

10 to 50 percent by weight, preferably 15 to 40 percent by weight and preferably approximately 20 percent by weight of the amount of material (3) or, in the case of a sealing mat with a fabric layer and a nonwoven layer, is preferably approximately 40 percent by weight.

11. Sealing mat according to one of the preceding claims, characterized in that the weight of the swellable material is 100 to 600 g / m ² and in particular 400 to 600 g / m ² .

12. Sealing mat according to one of the preceding claims, characterized in that the swellable material (3) further comprises a proportion of a hydrophilic, swellable mineral substance, in particular bentonite, in particular a proportion of less than 50 percent by volume of the swellable material (3) , preferably a proportion of less than 20 percent by volume.

13. Sealing mat (10; 11; 12) according to one of the preceding claims, characterized in that at least one removable protective layer or at least one removable protective layer is applied on one side or on both sides.

14. Sealing mat (10; 11; 12) according to one of the preceding claims, characterized in that a permanently fastened, liquid-tight plastic sealing membrane (4) is arranged on one side thereof, which is in particular a multi-layer plastic sealing membrane certified for tunneling applications.

15. Sealing mat according to a dqr claims 1 to 13, characterized in that a permanently attached, liquid-tight plastic sealing sheet (34, 35) is arranged on each of its two sides, which is in each case in particular a multi-layer, certified plastic sealing sheet for tunneling applications.

16. Sealing mat according to claim 14 or 15, characterized in that on the side facing away from the sealing mat of the or at least one of the plastic sealing sheets (4, 34, 35) a textile fabric is fastened, in particular a textile composite, in particular a fleece.

17. Sealing mat (10; 11; 12; 36) according to one of the preceding claims, characterized in that it is formed as a web which has a strip on one side or on both sides, which is formed by only one of the textile fabrics and wherein one or both strips are provided with superabsorbent granules embedded in melted and re-solidified hot melt adhesive.

18. Sealing mat (10; 11; 12) according to one of the preceding claims, characterized in that covers (5, 6) are applied on both sides of the textile fabrics (1, 2), which covers at most through the textile fabrics in regular or incorrect fashion. regular distances are connected to one another, in particular by sewing (7).

19. A method for producing a sealing mat according to one of claims 1 to 18, characterized in that a first textile fabric (1), in particular a non-woven layer, a superabsorbent granulate and a hot melt granulate are sprinkled on the granulate layer (3 ) another textile fabric (2), in particular a non-woven layer or a Fabric, and that the textile fabrics are connected to one another by a heat effect melting the hot melt granulate and subsequent cooling, including the superabsorbent granulate.

20. A method for producing a sealing mat according to claim 19, characterized in that the sealing mat is produced as a sheet-like mat, two laterally offset textile fabrics being connected to one another in such a way that the sheet is provided with one or two lateral single-layer edge strips of where one or both edge strips are coated with super absorber and hot melt.

21. A method for producing a sealing mat according to claim 19 or 20, characterized in that the sealing mat is provided on one or both sides with a removable or degradable protective layer, in particular a protective film or a sprayed-on protective layer, and one with the protective layer on the outside Roll is wound.

22. Use of a sealing mat according to one of claims 1 to 18 for sealing in civil engineering, in particular tunnel construction.

23. Use according to one of claims 1 to

18, characterized in that one of the textile fabrics (1, 2), in particular a fleece layer, is placed directly on the structure (14; 24) to be protected.

24. Use according to claim 22 or 23, characterized in that the sealing mat (10, 11) is placed directly on the outside of the tunnel vault in a mining tunnel vault (14) with one of its water-permeable textile fabrics (1, 2), in particular a non-woven layer and subsequently covered with at least one plastic sealing layer (15).

25. Use according to claim 22, wherein the sealing mat (10) in an underground tunnel arch is sealed by means of at least one plastic sealing layer (15) against the excavation side or its shotcrete layer (21) or the tubbings.

26. Use according to claim 25, wherein the sealing mat is arranged directly with one of its textile fabrics on the outside on the inner vault (24) of the underground tunnel vault.

27. Use according to claim 25, wherein the

Sealing mat is covered on its side facing away from the breakout side by a further plastic sealing layer.

28. Use according to one of claims 25 to 27, wherein at least one of the plastic sealing layers is a certified, in particular multi-layer, plastic sealing sheet for tunnel structures.

29. Use according to claim 28, wherein the plastic sealing sheet lying on the outside has an attached layer of textile composite material, in particular a non-woven layer.

30. Use according to one of claims 22 to 29, wherein in the sealing mat the one layer consists of a textile composite, in particular fleece, and the other layer consists of a woven, knitted or knitted fabric, this other layer facing the breakout side or from it is turned away.

31. Use according to one of claims 2 to 31, wherein individual sections sealed by the sealing mats are formed by partition profiles.

32. A sealing mat (30), fixed with a swelling upon supply ^• of aqueous liquid material (26), characterized in that the mat comprises a layer (25) of a textile fabric as a support layer on which position on one side or both sides of a superabsorbent means of an adhesive is.

33. Sealing mat according to claim 32, characterized in that the mat has only one layer (25).

34. Sealing mat according to claim 32, characterized in that the mat further comprises the position on one or both sides at least partially covering, more or less liquid-permeable or liquid-tight covers (28, 29).

35. Sealing mat according to one of claims 32 to 34, characterized in that the super absorber is fixed on the layer by means of hot melt adhesive.

36. Sealing mat according to one of claims 32 to 35, characterized in that the layer of a textile composite, in particular a nonwoven, in particular an endless fiber nonwoven, or that the layer is formed by a woven, knitted or knitted fabric.

37. Sealing mat according to one of claims 32 to 36 and with the properties of layer or absorber layer or adhesive according to one of claims 7 to 18.

38. A method for producing a sealing mat according to any one of claims 32 to 37, characterized in that on a layer of a textile fabric, in particular a nonwoven fabric, a superabsorbent material in powder and / or granulate form together with an adhesive or after application an adhesive is applied and fixed to the layer by the adhesive.

39. The method according to claim 38, characterized in that the adhesive is a hot melt, which is preferably also applied in powder or granule form, and that the fixation is carried out by melting and solidifying the hot melt.

40. geomembrane comprising a plastic

Sealing membrane (1, 2, 3) as the carrier layer and one lying on one side of the carrier layer, in particular directly on top of it, second layer made of a material that swells when water is absorbed.

41. Sealing membrane according to claim 40, characterized in that a further plastic sealing membrane (11, 12, 13) on the second as the third layer

Layer (4) is arranged, and in particular is arranged directly on it, so that the layer (4) lies between the plastic sealing sheets or that a textile fabric is provided as the third layer, which in particular likewise lies directly on the second layer ,

42. Sealing membrane according to claim 40 or 41, characterized in that the second layer (4) contains a super absorber.

43. Sealing membrane according to one of claims 40 to 42, characterized in that the second layer (4) contains an adhesive, in particular a hot melt adhesive and / or that the second layer contains a plastic, in particular a foamed plastic.

44. Sealing membrane according to one of claims 40 to 43, characterized in that the adhesion of the layers to one another is effected predominantly or exclusively by the second layer (4).

45. Sealing membrane according to claim 42, characterized in that the superabsorbent is in granular form in sizes between fine granules to coarse granules, in particular that two or more different granule sizes are present.

46. Sealing membrane according to claim 43, characterized in that the amount of adhesive, in particular the amount of hotmelt adhesive, is 10 to 40 percent by weight, preferably 20 to 30 percent by weight and preferably approximately 25 percent by weight of the second layer.

47. Sealing membrane according to one of claims 40 to 46, characterized in that the layer (4) comprises a portion of a swellable mineral substance, in particular bentonite, in particular a portion of less than 50 volume percent, in particular a proportion of less than 20 volume percent.

48. Sealing membrane according to one of claims 40 to 47, characterized in that the layer (4), the carrier layer (1,2,3) and optionally the further one

Plastic sealing membrane (11, 12, 13), covered over the entire surface or that the second layer (4) covers the first layer and, if appropriate, the further plastic sealing membrane only partially.

49. Sealing membrane according to one of claims 40 to 48, characterized in that the plastic sealing membranes (1,2,3,11,12,13) for tunnel seals are certified plastic sealing membranes, and in particular multilayer plastic sealing membranes with at least one sealing layer (2; 12) and a signal layer (3; 13).

50. A method for producing a sealing membrane according to any one of claims 40 to 49, characterized in that a mixture of superabsorbent and adhesive, in particular hot melt adhesive, is applied to a plastic sealing membrane and this is heated and subsequently cooled again, optionally on the heated one Mixture, the further plastic sealing membrane (11, 12, 13) is applied, and / or a mixture of plastic, in particular foamed plastic and superabsorber, is applied, in particular extruded, to the plastic sealing membrane.

51. Use of a geomembrane according to one of claims 40 to 49 for sealing in building or civil engineering and preferably in tunnel construction.

52. Use according to claim 51, characterized in that the second layer (4) lies directly on the building, in particular the tunnel vault.

53. Superabsorber for use in building waterproofing, in particular according to claims 1 to 52, characterized in that it is obtained by polymerizing ethylenically unsaturated acid groups bearing monomers, for example from acrylic acid, methacrylic acid, vinyl acetic acid, maleic acid, 2-acrylamido-2-methylpropanesulfonic acid, vinyl sulfonic acid, (meth) allylsulfonic acid or mixtures thereof in the presence of crosslinking agents.

54. Superabsorber according to claim 53, characterized in that acrylic acid is used as the ethylenically unsaturated monomer carrying acid groups.

55. Superabsorber according to claim 43 or 54, characterized in that the acidic monomers are neutralized at least to at least 50 mol%, preferably to 70 to 95 mol%, and in particular are present as the sodium, potassium or ammonium salt or mixtures thereof.

56. Superabsorber according to one of Claims 53 to 55, characterized in that the polymers used contain up to 10% by weight of further C σ monomers which can be copolymerized with the monomers bearing acid groups to modify the properties, in particular as comonomers (meth) acrylamide, (meth) acrylonitrile , Vinyl pyrrolidone, vinyl acetamide, hydroxyethyl acrylate, alkylaminoalkyl (meth) acrylates, alkylaminopropylacrylamides, acrylamidopropyltrimethylammonium chloride or mixtures thereof.

57. Superabsorber according to one of claims 53 to 56, characterized in that the crosslinking agents are used in the form of monomers containing at least two ethylenically unsaturated double bonds, the crosslinking agent content being in particular 0.1 to 5% by weight, based on the monomers used.

58. Superabsorber according to one of claims 53 to 57, characterized in that the superabsorbent polymers have a teabag retention of greater than 30 g / g, preferably greater than 35 g / g, an absorption of greater than 30 g / g, preferably greater than 40 g / g and an absorption, measured under a pressure of 21 g / cm ² , of greater than 15 g / g, preferably greater than 20 g / g for 0.9% saline.

59. Superabsorber according to one of claims 53 to 58, characterized in that their particle sizes are in a range from 60 to 500 μm, particularly preferably in a range from 150 to 350 μm. S

60. Hotmelt adhesive for combination with superabsorbers, in particular according to one of claims 53 to 59, for building seals _/ in particular according to claims 1 to 52, characterized in that the hotmelt adhesive is based on polyamides, polyesters, polyester lyurethanes and copolymeric ethylene vinyl alcohols is formed, polyamides are preferably used.

61. Hotmelt adhesive according to claim 60, characterized in that the polyamide / ethylene vinyl alcohol mixture is provided with a weight fraction of the copolymeric ethylene 5 vinyl alcohol of 15 to 45% by weight and particularly preferably 20 to 35% by weight.

62. Hotmelt adhesive according to claim 60 or 61, characterized in that it is set to a melting range of 90 to 150 ° C, particularly preferably 100 0 to 140 ° C.