Liner tube for renovating defective sewer pipes and method for the production thereof

Abstract

The invention relates to a liner tube for renovating defective sewer pipes and to a method for the production, installation and use thereof.

Description

[0001] Lining hose for the repair of defective sewer pipes and method for its manufacture

[0002] The invention relates to a lining hose for the rehabilitation of defective sewer pipes and a method for the manufacture and installation of such a hose and its use.

[0003] In the field of trenchless rehabilitation of defective pipelines, such as damaged sewers, lining tubes are increasingly being used. These tubes consist of one or more layers of fiberglass laminate impregnated with a liquid resin, arranged as overlapping wound or laid fiber strips around an inner foil liner. On the outside, the laminate is surrounded by an outer foil liner, which prevents harmful substances, particularly styrene, from escaping the resin into the surrounding soil. These lining tubes, also known as inliners, are pulled into the pipe to be rehabilitated. After insertion, their ends are sealed with packers, expanded using compressed air, and cured by UV light or, alternatively, by the introduction of hot steam.

[0004] A lining hose mentioned above and a method for manufacturing such a hose are known, for example, from WO-A 95 / 04646.

[0005] In recent years, the cured-in-place pipe (CIPP) lining method for pipe rehabilitation, particularly trenchless sewer pipe rehabilitation and pressure pipe rehabilitation, has increasingly come into focus due to its undeniable advantages in terms of effort and cost. In trenchless sewer rehabilitation, for example, the fiberglass liner system with UV or steam curing involves first inserting a thick-walled, high-density polyethylene (HDPE) film as a slip sheet into the pipe to be rehabilitated. This film, usually in a semicircular cross-section, is applied to the inner wall of the pipe. Instead of a slip sheet, a preliner (also called a preliner film) is inserted into the pipe to be rehabilitated, particularly in the synthetic fiber liner system with hot water or steam curing.A preliner, usually also made of HDPE, is a thick-walled film that completely lines the pipe. It prevents direct contact between the liner and the inner pipe wall by pressing the preliner against the pipe's inner wall. After the (optional) installation of a sliding film or preliner, a flexible liner, also known as a pipe liner, is pulled into the pipe (pulling-in method) or inverted (inversion method), with the liner sliding over the sliding film or preliner. This prevents damage to the liner from the pipe's inner wall or objects inside the pipe. Furthermore, the friction between the liner and the sliding film or preliner is very low, facilitating the insertion process.

[0006] In a fiberglass-reinforced tubing system with UV or steam curing, such an insert tubing typically comprises an outer tubing (outer tubing film) and an inner tubing (inner tubing film), both designed as tubing film. Between these layers, a carrier material, such as fiberglass or nonwovens, is inserted, impregnated with reactive polymer resin (resin carrier system). Examples of commercially available reactive polymer resins include UP resins (polyester or unsaturated polyester resins), VE resins (vinyl ester resins), or EP resins (epoxy resins). The reactive polymer resin is preferably an unsaturated polyester resin (UP resin) with α,β-unsaturated monomers, such as styrene. Commercially available resins are, for example, unsaturated polyester resins of type 1140 according to Table 3 of DIN 16 946-2 corresponding to group 3 in Table 1 of DIN 18 820.The resins are cured using photoinitiators, for example, in the case of unsaturated (UP) or deionized (VE) resins. Curing can also be thermal. The liner is inflated from the inside of the pipe by compressed air directed against the mechanically stable inner liner until the outer liner rests against the inner pipe wall, the sliding film, or the preliner. In other words, the liner is "erected" to allow the resin to be cured—for example, using UV light from a UV light source slowly drawn through the interior of the inflated liner. Depending on the design of the liner's inner liner, it either remains in the pipe or is removed.

[0007] To prevent unwanted, premature hardening of the resin before insertion into the pipe to be rehabilitated (especially during storage), the outer film of the liner must have a protective layer or consist of one that prevents premature exposure of the resin to UV radiation or short-wavelength visible light, thus preventing premature resin hardening. The inner film of such a liner, on the other hand, must have very good permeability to UV radiation and short-wavelength visible light. This enables the curing process, which, when the liner is inflated inside the pipe, is carried out by a radiation source that is passed along the inside of the liner, i.e., within the inner film.

[0008] It is known from the prior art to laminate the outer or inner film of the tubing on the side facing the resin-impregnated carrier material with a nonwoven fabric made of, for example, polyethylene, polypropylene, polyester, or polyamide fibers. The resin-impregnated glass fibers, which constitute the carrier material, or resin-impregnated tapes applied to the tubing film by winding, come into contact with the nonwoven fabric. This allows the resin to reach and penetrate the nonwoven fabric laminated to the tubing, enabling it to bond firmly and practically inseparably with the fabric. Furthermore, the use of a nonwoven fabric has the advantage that excess air can be removed from the system, as the glass fibers and resin adhere to the nonwoven fabric, displacing the air in the process.

[0009] EP 0 342 897 A2 describes a multilayer film comprising a polyamide layer as a first outer layer and an ionomer sealing layer as a second outer layer, with an adhesion promoter layer between these two outer layers. When used in pipe rehabilitation, the polyamide layer is bonded to a fibrous nonwoven fabric by heating, and this fabric is then impregnated with a curable resin. After insertion into a pipe to be rehabilitated and after curing of the resin by UV radiation, the two ends are sealed together via the ionomer sealing layer. A disadvantage of a multilayer film disclosed in EP 0342 897 A2 is that it has a weak point, at least in the area of ​​the seal.

[0010] In contrast, newer inner liners for pipes often have a polyethylene layer as the first outer layer, which, when installed, faces the interior of the rehabilitated pipe (in the direction of the transported medium), and a polyamide layer as the second outer layer, which, when installed, faces the pipe wall of the rehabilitated pipe. Polyamide exhibits very high wear resistance, high strength, stiffness, and toughness, and also good chemical resistance. In a pipe liner, the polyamide serves primarily as a barrier against monomers such as styrene.

[0011] Tubular films are preferably produced by blown film extrusion on blown film extrusion lines. In this process, after extrusion and the exit of the polymer melt from an annular die, followed by blowing the melt into a bubble and cooling of the resulting tubular film, a process called flattening (using squeeze rollers) takes place. Afterward, the tubular film is wound up like a flat film. During this process, virtually all the air contained in the bubble is squeezed out. This flattening creates two edges at the outer boundaries of the tubular film's width, which is unavoidable with this method. The formation of these edges in a tubular film can be roughly compared to folding a piece of paper.

[0012] It has been observed that during the flattening process of the manufacturing process described above, as well as during flat storage (i.e., before installation in a pipe requiring rehabilitation), mechanical weak points, such as (micro)holes, develop at the folded edges of both inner and outer liners. These weak points can lead to tears and even larger holes in the inner or outer liner when the liner is inflated. The cause of these weak points is likely that the edges become thinner during storage, possibly due to the flow exerted by mechanical pressure. Particularly in the case of inner liners manufactured using blown film extrusion, it has been found that the folded edges thin more and more over time during storage. This results in premature tearing at the resulting weak points.

[0013] To ensure optimal adhesion of the lining tubes ("cured-in-place pipe liners") to the inner walls of the sewer during expansion or "installation"—a fundamental requirement for high maximum mechanical load-bearing capacity—they are typically manufactured with an outer diameter that is 5 to 10% smaller than the inner diameter (DN) of the sewer pipe being rehabilitated. This slight undersize, due to the additional expansion of the lining tube during the process, results in an improved surface finish of the cured laminate and allows for the compensation of minor diameter variations within the sewer pipe.An elongation of more than 10% is not currently possible with known lining hoses of the prior art, such as those of WO-A 95 / 04646, as this poses the risk of overstretching and damaging the sensitive transparent inner film. This would cause the compressed air introduced during expansion to escape through the damaged inner film into the laminate, blowing out the liquid resin at the affected point. After the resin has cured, this typically results in a mechanical weak point and leak, which, if it can be detected and repaired at all, is extremely difficult.

[0014] On the other hand, it is problematic in practice to manufacture the previously described lining tubes with a diameter larger than the inner diameter of the sewer pipe to be rehabilitated, as the laminate and the outer foil tube will wrinkle in this case, which is undesirable in the rehabilitated sewer and leads to shadowing during curing with UV light, which prevents the reaction resin from fully curing in the case of larger wall thicknesses.

[0015] For the reasons mentioned above, the rehabilitation of pipelines with a nominal diameter (DN) between 150 mm and 1200 mm required more than 40 different basic types of lining liners, each with a specific DN and a specially manufactured inner foil liner, to provide an optimally adapted lining liner for every pipe diameter. This liner, after being pulled in, expanded, and cured, guarantees maximum mechanical strength and leak tightness. It goes without saying that maintaining a sufficient number of these typically seamless inner foil liners, as well as the individual manufacturing of the laminate to the required diameter, represents a significant logistical undertaking, which makes the production of the lining liners expensive.

[0016] Furthermore, this significantly restricts flexibility in handling customer requests: If a lining hose with a suitable DN is not in stock, it must first be manufactured, which takes time. However, if a lining hose for a slightly lower DN were already available, it would be a significant advantage if it could also be used for the higher DN requested by the customer. Another shortcoming of the known lining hoses is that sewer pipes where the inner diameter changes abruptly in a section, for example from DN 300 mm to DN 400 mm, can only be lined with the previously described lining hoses with considerable uncertainty, or with considerable effort by inserting and connecting two separate lining hoses of the corresponding diameter.

[0017] From WO2022 / 128218A1, a lining tube is known which has an inner foil tube and a radially expandable layer of highly elastic fiber material arranged around it, which is impregnated with a curable reactive resin. The lining tube overcomes the aforementioned shortcomings by the fact that the inner foil tube has a longitudinally extending connecting section which joins two parallel circumferential sections of the inner foil tube to form a circumferentially closed inner foil tube with a defined nominal diameter, and that the connecting section has a predetermined breaking point extending along the inner foil tube which can be detached circumferentially by introducing a pressure medium into the inner foil tube in order to expand the inner foil tube and the layer of fiber material arranged on it radially beyond the nominal diameter.Although the lining hose covers a wide range of pipe diameters, its manufacture and handling are comparatively complex.

[0018] A disadvantage of all the above-mentioned PE / PA or PE / HV / PA films used as inner tubing liners in the prior art is, among other things, their insufficient mechanical strength and inadequate elongation.

[0019] In the worst case, insufficient mechanical properties of the inner film of the hose lead to a bursting of the film when the inner film of the insert hose (hose liner), which is designed as a hose, is inflated.

[0020] The same applies to the outer films for hoses described in the prior art, which are used for the production of lining hoses. Here, too, the elongation capacity is currently insufficient.

[0021] However, if the liners (inner and outer) already possess insufficient elasticity and mechanical strength (and are also unstable under weathering and particularly prone to failure at low temperatures around or below freezing), a lining liner with sufficient elasticity to repair or rehabilitate even large dimensional changes in pipe diameters (DN) cannot be provided with such liners. This is because all liners within the pipe, both the inner and outer liners – especially in contact with the resin-impregnated carrier material – must exhibit very high elasticity while maintaining high mechanical strength, which must also be unaffected by external influences such as weather (e.g., temperature and humidity).

[0022] Accordingly, it is an object of the present invention to provide a lining hose that is easy to handle and inexpensive to manufacture, which makes it possible to rehabilitate sewer pipes with different internal diameters or with internal diameters that change over the length of the sewer pipe, as well as manholes, with one and the same lining hose.

[0023] Therefore, the object of the present invention is to enable the simple repair of so-called "dimensional jumps" in the diameter DN of the sewer pipe to be rehabilitated using the pipe lining technology, or to enable this repair in the simplest possible way.

[0024] This problem is solved according to the invention by a lining hose with at least the features of claim 1.

[0025] A further object of the invention is to provide a method by which such a lining hose can be installed in a sewer to be rehabilitated. This object is achieved according to the invention by a method with the features of claim 11.

[0026] Further features of the invention are described in the dependent claims.

[0027] Therefore, the invention relates to a lining hose for the rehabilitation of a defective sewer pipe or sewer shaft, comprising an inner foil hose, a tubular layer made of a carrier material arranged around it and impregnated with a curable reactive resin, wherein the inner foil hose has a multilayer film comprising at least one layer of one or more homo- or copolymers of polyolefins (hereinafter also referred to as polyolefin layer) and at least one barrier layer of one or more homo- or co-polyamides (hereinafter also referred to as polyamide layer (PA)) arranged on this layer.

[0028] where,

[0029] the barrier layer consists of one or more homo- or co-polyamides, including at least one polyblock amide,

[0030] and / or

[0031] the layer of one or more homo- or copolymers of polyolefins wholly or partially contains at least one metallocene linear low-density polyethylene (m-LLDPE), wherein the barrier layer of one or more homo- or copolymers is arranged directly on the layer of a carrier material (hereinafter referred to as inner film tube according to the invention).

[0032] According to the underlying concept of the invention, a lining hose with a circular cross-section and a cylindrical shape when expanded is designed in such a way that it can adapt to the different diameters of a sewer pipe during expansion. This advantageously makes it possible to manufacture the lining hose as an endless hose, as described in WO-A 95 / 04646, and to transport it to the construction site.

[0033] The lining tube comprises an inner foil tube on which, for example, at least one layer of a helically wound or alternatively circumferentially laid carrier material, in particular fiber tape, especially a glass fiber tape or glass fiber fleece, is arranged, which is impregnated with a liquid reactive resin that can preferably be cured by UV light. This is preferably followed by a glass fiber tape (longitudinal tensile tape) with glass fibers oriented longitudinally in the direction of the lining tube, in particular glass fiber rovings, which transfers the tensile forces during the installation of the lining tube, hereinafter also referred to as a "liner", into a sewer pipe or manhole.

[0034] The inner film tube 10 according to the invention (also called "tube inner film" or simply "inner film") is preferably seamlessly formed from a multilayer film or composite film, which—in its simplest form—comprises a first inner layer made of a polyolefin (polyolefin layer), in particular polyethylene (PE), and a barrier layer made of polyamide (PA) (polyamide layer) arranged on this, which are connected to each other via a bonding layer, preferably an adhesion promoter (HV). According to the invention, the multilayer films can contain several layers, including at least one layer consisting predominantly of polyethylene (PE), at least one adhesion promoter layer (HV), and at least one polyamide layer (PA).

[0035] For the production of the at least one polyamide layer PA in the multilayer films according to the invention, which are suitable for use as both inner and outer tubular films, at least one homo- and / or copolyamide is suitable. Suitable homo- or copolyamides are preferably selected from the group consisting of thermoplastic aliphatic, semi-aromatic, or aromatic homo- or copolyamides. These homo- or copolyamides can be selected from diamines, such as aliphatic diamines with 2-10 carbon atoms, in particular hexamethylenediamine, and / or aromatic diamines with 6-10 carbon atoms, in particular p-phenylenediamine, and / or from aliphatic dicarboxylic acids and / or aromatic dicarboxylic acids with 6-14 carbon atoms, such as adipic acid, terephthalic acid, or isoterephthalic acid, and / or from lactams with 4-10 carbon atoms, such as 8-caprolactam.

[0036] Preferably, the polyamides PA 6, PA 11, PA 12, PA 66, PA 6,10, PA 6,12, PA 666, PA 61, PA 6T or corresponding copolymers or mixtures of at least two of the aforementioned polyamides are used according to the invention.

[0037] The polyamide layer of the multilayer films according to the invention preferably has a layer thickness of 5 pm to 200 pm, particularly preferably of 15 pm to 90 pm and most preferably of 20 pm to 60 pm.

[0038] For the production of the at least one adhesion promoter layer (HV) of the multilayer films according to the invention, conventional adhesion promoters familiar to those skilled in the art can be used, e.g., a modified thermoplastic polymer, preferably in particular a modified olefin homo- or copolymer. The modification is preferably carried out with at least one organic acid or at least one preferably cyclic organic anhydride, preferably with maleic anhydride (MSA or MAH). Other functional groups can also be introduced into the olefin homo- or copolymers so that these modified polymers act successfully as adhesion promoters. In particular, functional groups such as, but not limited to, acrylate, alcohol, acetate, or epoxy groups are suitable.

[0039] The thickness of the adhesion promoter layer of the multilayer films according to the invention is preferably between 1 pm and 50 pm, particularly preferably between 2 pm and 20 pm.

[0040] To produce the at least one polyolefin layer, in particular the polyethylene (PE) layer, of the multilayer films according to the invention, at least one thermoplastic olefin homopolymer or copolymer can be used, for example, those of α,β-unsaturated olefins with 2-10 carbon atoms. Ethylene homopolymers (polyethylenes, PE), preferably LDPE (high-density polyethylene in the range of 0.86-0.93 g / cm³), are particularly suitable. 3 ), LLDPE (Linear Low Density Polyethylene), HDPE (High Density Polyethylene in the range of 0.94 and 0.97 g / cm³) 3) and mPE (PE polymerized on the basis of metallocene catalysts), propylene homopolymers (polypropylene, PP), butylene homopolymers (polybutylene, PB) and isobutylene homopolymers (polyisobutylene, PI) or mixtures of at least two of the aforementioned polymers.

[0041] Within the scope of this invention, it has been found that the best mechanical properties of the multilayer films according to the invention are preferably obtained when the at least one polyolefin layer, in particular PE layer, contains wholly or partially an mLLDPE (co)polymer to a proportion of preferably at least 30 wt.%.

[0042] The layer thickness of the at least one polyolefin layer of the multilayer film according to the invention, with a proportion of mLLDPE of preferably at least 30 wt.%, is preferably 10 pm to 500 pm, particularly preferably 20 pm to 400 pm, very particularly preferably 30 pm to 300 pm and most preferably 40 pm to 200 pm.

[0043] The thickness of the at least one polyolefin layer of the multilayer film according to the invention, with a proportion of mLLDPE of preferably at least 30 wt.%, preferably amounts to at least 15% of the total thickness of the multilayer film, preferably to at least 25%, and particularly preferably to 30% to 95%. Individual or all layers of the multilayer films according to the invention can, if advantageous or necessary, each contain additives independently of one another.These may be selected from the group comprising antistatic agents, antioxidants, oxygen scavengers, antiblocking agents, antifog agents, antimicrobial agents, dyes, color pigments, stabilizing agents, preferably heat stabilizers, process stabilizers, process aids, flame retardants, nucleating agents, crystallizing agents, preferably crystal nucleating agents, lubricants, optical brighteners, flexibilizers, sealing agents, plasticizers, silanes, spacers, fillers, peel additives, waxes, wetting agents, surfactants, preferably surfactants, UV stabilizers, and dispersants. The proportion of additives in the layers may be at least 0.01–20% by weight, preferably at least 0.1–10% by weight (in each case based on the total weight of a single layer).

[0044] The total layer thickness of the multilayer film according to the invention is preferably between 20 and 2000 pm, particularly preferably between 50 and 1500 pm, most preferably between 70 and 1000 pm, and particularly between 80 and 400 pm.

[0045] In order to advantageously use the multilayer film according to the invention as an inner liner in pipe rehabilitation using pipe lining technology (so), it is advantageously at least partially transparent to UV radiation, i.e., electromagnetic radiation in a wavelength range of 200 to 450 nm, preferably to at least 60%, particularly preferably to at least 80%, and most preferably to at least 90%. Here, a particularly high transmission for UV and (short-wave) visible light in the wavelength range of 200 to 450 nm is crucial. A UV source can then effectively act on the carrier material, preferably impregnated with reactive resin, through the multilayer film according to the invention, in this case through the inner liner, in order to cure it during liner installation.

[0046] In a preferred embodiment, the multilayer film according to the invention is not only at least partially transparent to UV radiation, but – for the same reason as above – also at least partially transparent to short-wavelength visible light (i.e., electromagnetic radiation in a wavelength range of 400 to 500 nm, preferably 400 to 450 nm), preferably to at least 80%, particularly preferably to at least 90%. In contrast, the multilayer film according to the invention, when used as a tubular outer film, is largely UV- and light-tight, as is required for the outer films described in DE 10 2009 041 841. In this case, the outer film absorbs or reflects both UV and (shorter-wavelength) visible light to over 90%, preferably over 99%.Accordingly, the outer film according to the invention constitutes a UV and light protection film to prevent the resin-impregnated carrier material from hardening prematurely due to external exposure to electromagnetic radiation, such as sunlight. This is because premature hardening would render the lining tube according to the invention, which is obtained with the multilayer films according to the invention, unusable. The required UV and light protection in the outer films according to the invention for the lining tubes according to the invention is achieved by adding, for example, color pigments and / or UV absorbers. Depending on the concentration c of these additives and the layer thickness d in which these additives are incorporated, the desired absorption or extinction of electromagnetic radiation can then be adjusted according to Lambert-Beer's law.

[0047] The multilayer films according to the invention can be produced as tubular films by (co)-extrusion, particularly preferably by blown film (co)-extrusion, preferably without a sealing seam. Alternatively, the multilayer film according to the invention can be obtained in the form of a tubular film as a cast film by cast (co)-extrusion or as another type of flat film. Such films can then be sealed to form a tube. Embossing, stretching, conditioning (reversible absorption of moisture, preferably water, by a thermoplastic polymer such as homo- or copolyamide or by the entire multilayer film) and / or printing of the multilayer film according to the invention can be advantageous. However, the multilayer film according to the invention is preferably not oriented. The multilayer film according to the invention is preferably transparent when used as an inner lining film in a tubular liner or lining tube.

[0048] As mentioned above, a further object of the present invention is the use of the multilayer film according to the invention, preferably in the form of a tubular film, as an inner tube (inner tube film) of an insert tube for the rehabilitation of underground pipes, preferably underground sewer pipes. The multilayer film according to the invention, preferably in the form of a tubular film, allows, due to its at least partial permeability to UV radiation, the curing of a reactive polymer resin or a carrier material impregnated with reactive polymer resin, which is located between an outer single- or multilayer tube (outer tube film) and the inner tube (inner tube film) designed according to the invention.Preferably, the multilayer film according to the invention is transparent as the inner film of the tube, and further preferably, the multilayer film according to the invention is contact-transparent or opaque as the outer film of the tube.

[0049] The preferred carrier material according to the invention is glass fiber fabric, synthetic fiber felts (such as needle felts), nonwovens and / or non-woven textile products or textiles (such as knitted tubes), each impregnated with at least one reactive polymer resin, preferably with at least one unsaturated polyester resin (UP resin) and α,β-unsaturated monomers, such as styrene. Glass fiber reinforced plastics (GFRP) are a corresponding example. In addition to UP resins, EP and VE resins are also suitable.

[0050] In principle, any material that is absorbent for resin and liquids, and can therefore be soaked, is suitable as a carrier material for impregnation.

[0051] Within the scope of this invention, it is preferred that the (resin-impregnated) carrier material is also configured to allow the enormous elongation of the lining hose. Successful measures and possibilities for this can be found, for example, in WO2022 / 128218A1.

[0052] The invention also relates to an insertable liner for insertion into an underground pipe, in particular a sewer pipe, for the purpose of its rehabilitation. The insertable liner comprises a liquid-tight multilayer film according to claim 1 as an inner liner (inner liner, preferably in the form of a liner) and preferably also a liquid-tight outer liner according to the invention (outer liner), which faces the pipe wall.

[0053] It is not advantageous if the inner liner of the hose has particularly good mechanical properties, especially very high elongation, while the outer liner would not stretch accordingly. Therefore, the same excellent elongation properties for the highly elastic hose liner or lining hose invented here, which allows for the successful rehabilitation of several different DN dimensions in identical or different sewers, are preferably achieved when the inner and outer liners can expand excellently and stably (radially), and when the resin-impregnated carrier material also permits this expansion, i.e., when the resin-impregnated carrier material "cooperates" in this process.

[0054] Within the scope of this invention, the use of conventional, non-inventive outer liners (with insufficient elasticity) is nevertheless possible, and may even be preferred in some cases. In this case, however, the outer liner must either have an expansion joint or a predetermined breaking point that opens when the inventive lining hose is erected for the rehabilitation of the sewer pipe. In this way, the conventional outer liner does not impede the outstanding elongation or elasticity of the inventive inner liner. Such a predetermined expansion joint is described, for example, in DE 102011 103 001 A1.

[0055] Between the inner and preferably also the outer hose according to the invention, a UV-curable carrier material, preferably glass fiber material, is provided, which is preferably impregnated with a reactive, unsaturated resin. After curing, the rehabilitated sewer pipe is formed from this impregnated carrier material. After curing, the inner multilayer film according to the invention is preferably pulled off and removed from the sewer pipe lined with the carrier material. Alternatively, the inner film of the hose remains in the rehabilitated pipe. A person skilled in the art has certain options for adjusting this.

[0056] The manufacture of such insert tubes is described in WO 2007 / 054350 Al or EP-B 1 155256.

[0057] The outer tubular film according to the invention is preferably designed to be stretchable like the inner tubular film and can have analogous layers and components. The outer film is multilayered. In contrast to the inner tubular film, it absorbs and / or reflects UV radiation and / or short-wave visible light. The outer film is therefore a UV and light protection film and protects the resin-impregnated carrier material from premature curing (by external radiation). The outer tubular film can be either opaque or at least contact-transparent. Preferably, the multilayer tubular film used as the outer tubing of an insert tubing is at least contact-transparent and absorbs and / or reflects UV radiation and / or short-wave visible light.Such an external hose is described in WO 2010 / 075946 Al and DE 10 2010 023 764 Al, wherein this external hose preferably has the ingredients and properties described therein, preferably including the oxygen barrier layer, water vapor barrier layer or oil barrier layer also described therein.

[0058] The object of this invention is essentially achieved by the films according to the invention, which are used for the construction of the liners or the lining or insert tubes. By using these special films according to the invention, which relate to both the inner and outer tube films, lining or insert tubes or hose liners become available that perfectly fulfill the object of this invention and lead to a significant product improvement compared to the prior art.

[0059] Therefore, inner liners for hoses, in particular, must meet the highest requirements regarding their mechanical properties, such as tear resistance, tensile strength, elongation, splicing tendency, impact strength, and puncture resistance. The PE / PA or PE / HV / PA films used as inner liners in the prior art, or indeed all films of this type (regardless of the number of layers) with a PA outer layer, still require considerable improvement in this respect to offer even greater safety when used in lining hoses.

[0060] It became particularly evident that the polyamide layer of the inner (and outer) tubing films used in the prior art is extremely susceptible to weathering, especially temperature and humidity. It is known that the inner and outer tubing films described in the prior art tend to become significantly brittle in winter, particularly when their polyamide layer is located on (at least) one outer surface of the film. This is because, especially in winter, low temperatures around or below freezing often result in very low humidity, which regularly leads to embrittlement of the polyamide layer (since water is known to be a plasticizer for polyamide).This embrittlement, which the expert can immediately detect by touch, in turn leads to the formation of (micro)holes, cracks and overall to an undesirable stiffening of the polyamide layer, causing the films to fail during the installation of the lining hose.

[0061] A further objective of the present invention is therefore to provide multilayer films for the construction of lining tubes for trenchless sewer rehabilitation, which meet the high requirements regarding their mechanical stability - even under adverse weather conditions.

[0062] This problem is solved in the lining hose according to the invention by the multilayer films according to claim 1.

[0063] In the multilayer films according to the invention, which are both inner tube films and outer tube films for the construction of lining tubes with very high elongation, at least one layer contains an mLLDPE (co-)polymer to a proportion of more than 30 wt.%, preferably more than 50 wt.%, particularly preferably more than 70 wt.% and most preferably more than 80 wt.% to 100 wt.%.

[0064] Metallocene low linear density polyethylenes (mLLDPE) are linear polymers with low density. They are ethylene copolymers produced via metallocene catalysis, in which 1-hexene (and in some cases 1-octene) is added as a further comonomer alongside ethylene.

[0065] The portfolio includes a wide variety of types with a density of approximately 902-936 kg / m³. 3and MFI values ​​of approximately 1.3–20 g / 10 min, covering segments such as films, injection molding, and compounding. Gas-phase technology with hexene as a comonomer offers several advantages, particularly for low-density materials used in film production. Key attributes include exceptional tear resistance, high dart drop, high elongation, and excellent appearance combined with very good processability.

[0066] mLLDPE polymers are used in the following applications:

[0067] - Cast and blown films,

[0068] - Stretch hood / stretch film,

[0069] - Multilayer films for food and non-food applications, - Laminating films,

[0070] - Durable and freezer-resistant bags and sacks.

[0071] Special properties of mLLDPE polymers include:

[0072] - Excellent workmanship thanks to the latest mLLDPE generation,

[0073] - Very high puncture resistance (dart drop),

[0074] - Very high tensile strength,

[0075] - Excellent sealing properties.

[0076] Typical examples of mLLDPE are (not exhaustive):

[0077] Sabic: SUPEER™ mLLDPE, e.g., Supeer 7118 LE or SUPEER™ Metallocene Linear Low Density Polyethylene (mLLDPE) 7118NE or SUPEER™ Metallocene Linear Low Density Polyethylene (mLLDPE) 7318BE,

[0078] or Exxon Mobil: EXCEED™ mLLDPE, such as the EXCEED 1018 series, Blown Film Resins, ExxonMobil Exceed™, e.g. Exceed 1327 CA

[0079] or LG Chemicals in Yeosu, South Korea (“LG Chem”): Lucene types, such as LUCENE SP 310 or LUCENE SP 311

[0080] or LUCENE SE1020A

[0081] or Ineos, Eltex PF types such as Eltex PF6112AA, PF6130LA, PF6212AA, PF6212KE, or PF6220KJ

[0082] or from REPSOL QUIMICA, SA, such as Resistex ® types, such as Repsol Resistex 1614 FG or Repsol Resistex ® 2710F or Repsol Resistex ® 3310F.

[0083] The use of mLLDPE for the production of (inner) films for pipe liners is known in the prior art, see EP 2 740 587 Al (there e.g. Example 1 and Comparative Example 1) or EP 2 835 395 Al (there Comparative Example V5).

[0084] However, the inventors here have recognized that the films described so far in the prior art, which are used for the construction of lining tubes, mostly contain a maximum of 30 wt% mLLDPE polymer in one layer, usually in the PE layer with the addition of a very high proportion of LDPE (such as Lupolen en 2420 F - see EP 2 740 587 Al or Lupolen 3010 D - see EP 2 835 395 Al).

[0085] In order to advantageously achieve a positive effect on the mechanical properties of the inner or outer film of the hose, at least one layer (of polyolefin) is preferably selected which contains the mLLDPE of preferably at least 30 wt.%, more preferably at least 50 wt.%, more preferably at least 70 wt.%, and most preferably at least 80 wt.%.

[0086] Neither the use of LDPE such as Lupolen 2420 F or Lupolen 3010 D, nor the use of conventional LLDPE (i.e., not an mLLDPE type, as described, for example, in EP 2379 625 Bl - Example 3) leads to such improved mechanical properties of the inner and outer films as those found within the scope of this invention. The examples and comparative examples shown below clearly demonstrate this.

[0087] The aforementioned mLLDPE (co)polymers have high impact strength, high heat resistance and very high flexibility even at low temperatures.

[0088] The high importance of polyamide (PA) in films used to manufacture lining tubes has already been mentioned above. At least one layer of polyamide is absolutely essential in such films simply to create a barrier against the polymerizable monomers (such as styrene or (meth)acrylates) used in the curable resins. Otherwise, the lining tube would not only dry out, but the leaching or seeping monomers in the resins could also enter the soil and groundwater, causing contamination that must be avoided at all costs.

[0089] Although polyamide, or at least a polyamide layer, is usually required in films used to manufacture lining hoses, as a polymer it has a number of disadvantages, which have already been described above. In particular, its embrittlement at low temperatures around or below freezing should be mentioned again.

[0090] The inventors have now discovered that all problems associated with polyamide or PA layers in inner and outer films used to construct lining tubes can be easily solved by adding even small amounts – a noticeable effect occurs even at a weight of 0.1% in the PA layer – of an elastomeric polyblock amide containing both soft, elastic segments and stiff, inflexible, hard polyamide blocks. One explanation for this effect, discovered by the inventors, is the high compatibility of these polyblock amides with the polyamide due to the polyamide blocks. Identical or very similar materials readily mix. Thus, the polyblock amide with its soft segments, due to the stiff polyamide blocks it also contains, is incorporated very homogeneously into the PA layer of the inner and outer films according to the invention.

[0091] Surprisingly, it has now been found that the soft segments in these polyblock amides result in a generally high degree of flexibility of the polyamide in the PA layer, particularly at low temperatures. Embrittlement of the polyamide layer practically ceases. The films according to the invention, with an outer layer of polyamide, remain consistently very soft and supple to the touch, even at temperatures below 0°C and at lower humidity levels, or even when water, which acts as a plasticizer, is largely eliminated.

[0092] Polyblock amides, which contain both soft elastic segments and stiff, inflexible, hard polyamide blocks, do not actually constitute plasticizers, since they are higher molecular weight polyblock amides, while the "classic" plasticizers are generally understood to be low molecular weight.

[0093] Particularly surprising was another effect resulting from the addition of these polyblock amides, which contain both soft elastic segments and stiff, inflexible, hard polyamide blocks, to the (outer) PA layer of the multilayer films according to the invention.

[0094] Completely unexpectedly, the impermeability of the polyamide layer to monomers or solvents, i.e., its barrier effect against these chemicals, was significantly enhanced. This is demonstrated by the measurements presented below. The inventors explain this by stating that the addition of these polyblock amides, which contain both soft elastic segments and stiff, inflexible, hard polyamide blocks, prevents the formation of so-called "micro-holes" in the layer structure of the polyamide layer.

[0095] One can therefore argue that the polyblock amides, which contain both soft elastic segments and stiff, inflexible, hard polyamide blocks, have a healing effect on inhomogeneities, embrittlement, and pitting of the (conventional, previously mentioned in the prior art) polyamide layer. This was unexpected. The reason for this is likely also the high flexibility or mobility of the soft segments in these polyblock amides, which causes this "healing effect." Furthermore, an interaction (very positive within the scope of this invention) between the polyblock amides, which contain both soft elastic segments and stiff, inflexible, hard polyamide blocks, and the hydrogen bonds of the polyamide used in the PA layer apparently occurs.

[0096] The very high homogeneity of the (outer) polyamide layer in the inner and outer films of the tubes according to the invention, achieved by adding polyblock amides containing both soft elastic segments and stiff, inflexible, hard polyamide blocks, could be demonstrated in various ways, for example by scanning electron microscopy or by atomic force microscopy (AFM), particularly on the PA outer layers of the films according to the invention that contain these polyblock amides. No defects were found in the PA layer of the films according to the invention, even at temperatures below 0°C.

[0097] For example, all so-called TPE-A polymers, which are thermoplastic polyamide elastomers, are suitable as polyblock amides, which contain both soft elastic segments and stiff, inflexible, hard polyamide blocks.

[0098] Examples of this product class include VESTAMID® E - Polyetherblockamide PEB A from Evonik.

[0099] Examples of these types include (selection):

[0100] VESTAMID® E40-S3, VESTAMID® E47-S1, VESTAMID® E47-S3, VESTAMID® E55-S3, VESTAMID® E62-S1, VESTAMID® E62-S3, VESTAMID® EX9200

[0101] The manufacturer describes the properties as follows:

[0102] PA 12 elastomers are block copolymers consisting of PA 12 segments and polyether segments (polyether block amide PEB A). Products rich in PA 12 exhibit the essential properties of PA 12; with increasing polyether content, the elastomeric character becomes more pronounced: the polymers become more flexible and have higher impact resistance at low temperatures.

[0103] Compared to competing thermoplastic elastomers, VESTAMID® E-molding compounds are distinguished by the following properties:

[0104] • Low density

[0105] • Good chemical and solvent resistance

[0106] • Easy to process and color, and easy to spray over.

[0107] • Excellently decoratable through thermal diffusion pressure

[0108] • Excellent cold impact resistance • Hardness and flexibility can be varied over a wide range

[0109] • High elasticity and good recovery properties

[0110] • Low temperature dependence of mechanical properties

[0111] • No volatile or migrating plasticizers

[0112] Polyether block amide, or PEBA, is a thermoplastic elastomer (TPE). It is known under the brand names PEBAX® (Arkema) and VESTAMID® E (Evonik Industries). It is a block copolymer obtained by polycondensation of a carboxylic acid polyamide (PA6, PA11, PA12) with a polyether containing terminal alcohol groups (e.g., polytetramethylene glycol PTMG, polyethylene glycol PEG). Its general chemical structure is: O-(CO-PA-CO-O-PE-O)n-H

[0113] Suitable types of Pebax® Grades include (selection): PEBAX® 7033, 6333, 5533, 5513, 4033, 3533 and 2533.

[0114] All PEBA types mentioned here as examples can be purchased commercially.

[0115] Within the scope of this invention, the addition of PEBA to the at least one polyamide layer in an amount of 0.1 to 60.0 wt.%, preferably 0.5 to 50.0 wt.%, particularly preferably 1.0 to 40.0 wt.% and most preferably 2.0 to 30.0 wt.% has proven to be ideal.

[0116] The advantages of the invention lie particularly in the fact that the inner films of the tubing according to the invention exhibit excellent mechanical properties such as extremely high elongation, low tendency to splinter, robustness, resistance, puncture resistance, and very high transmission in the wavelength range of 300 to 500 nm. Bursting of the films is thus practically impossible. These excellent mechanical properties are also maintained at low temperatures, for example below 0°C.

[0117] The advantages of the invention are particularly evident in the fact that the outer films of the tubing according to the invention exhibit excellent mechanical properties such as extremely high elongation, low tendency to splinter, robustness, resistance, puncture resistance, and very low transmission in the wavelength range of 300 to 500 nm, thus possessing a UV light-blocking effect. Bursting of the films is therefore practically impossible. These excellent mechanical properties are also maintained at low temperatures, for example below 0°C.

[0118] Specifically, it was found that the multilayer films according to the invention (inner and outer films of a lining liner for trenchless sewer rehabilitation) are characterized by excellent mechanical properties, in particular by very good elongation (determined according to the inflation test method described below), without any layer splitting. Preferably, the multilayer film according to the invention has an elongation up to the point of "splicing," i.e., a first tear of an inner film layer, of at least 20%, more preferably at least 25%, and most preferably at least 30%. The elongation up to bursting is preferably at least 100%, more preferably at least 110%, more preferably at least 120%, and most preferably at least 130% and even at least 140%.

[0119] Within the scope of this invention, inner tubular films (and also outer films) with a (radial) elongation of well over 200% were produced, which is unique in the prior art to date.

[0120] Using the inner and outer films of the hose according to the invention, lining hoses were produced that could be stretched well over 20% (see the examples below). This too is unique in the prior art.

[0121] The multilayer films according to the invention can, in particular for use as inner or outer liners for the production of lining tubes in trenchless sewer rehabilitation, have a layer structure with three, four, five or more layers. Three-layer, four-layer, five-layer or even higher-layer inner and outer liner films can be used according to the invention, wherein at least one of the polyol efin layers contains at least 30 wt.% mLLDPE and the at least one polyamide layer contains a polyblock amide that includes both soft elastic segments and stiff, inflexible, hard polyamide blocks.

[0122] The at least one PA layer can consist of the same or different PA materials. PA mixtures are also preferred. Further details are provided below. If two PA layers are present, an adhesion promoter can be applied. However, it is also possible to work without an adhesion promoter. The use of (conventional) adhesion promoters is preferred.

[0123] As mentioned above, it was surprisingly discovered that the multilayer films according to the invention, whether in the form of a multilayer tubular film (i.e., a multilayer film produced by (co)-extrusion, preferably by blown film (co)-extrusion, without a sealing seam) or a multilayer film sealed into a tube, are characterized by very good mechanical properties, in particular by very good elongation. When used as inner liners for the rehabilitation of underground pipes, they can therefore withstand the stresses encountered, especially during inflation within the pipe system, exceptionally well. This also applies to the mechanical stresses to which the film is subjected during transport. Furthermore, it was found that the multilayer film used as an inner liner for the tube is sufficiently tear-resistant when it is peeled off the resin / support system after the resin has cured.This allows the inner liner of the hose to be removed without leaving any residue, and no film fragments remain in the rehabilitated pipe. Furthermore, when used as an inner liner for the hose, the multi-layer film according to the invention provides a good barrier against the drying out of the resin.

[0124] The above also applies analogously to the (tubular) outer films according to the invention.

[0125] As mentioned above, a further object of the present invention is the use of the multilayer films according to the invention, preferably in the form of a tubular film, as an inner tube (tubular inner film) or as an outer tube (tubular outer film) of an insert tube for the rehabilitation of underground pipes, preferably underground sewer pipes. In this context, the multilayer film according to the invention, as a tubular inner film, preferably in the form of a tubular film, allows, due to its at least partial permeability to UV radiation, the curing of a reactive polymer resin or a carrier material impregnated with reactive polymer resin, which is located between an (inventive) outer multilayer tube (tubular outer film) and the inner tube (tubular inner film) designed according to the invention.The use of the multilayer films employed according to the invention can relate to all of the aforementioned embodiments.

[0126] It should be noted that features described in connection with an exemplary embodiment or an exemplary object can be combined with any other exemplary embodiment or with any other exemplary object.

[0127] When a term is referred to with an indefinite or definite article, such as "ein" in the singular, this also includes the term in the plural and vice versa, unless the context clearly indicates otherwise.

[0128] The term "encompass" as used here does not only include the meaning of "contain" or vice versa, but can also mean "consisting of" and "essentially consisting of".

[0129] The terms "position" or "layer" are synonymous.

[0130] The term “arranged” should be read in particular as “adjacent” or “bordering”.

[0131]

[0132] and

[0133] The following examples and comparative examples serve to illustrate the invention and are not to be interpreted restrictively.

[0134] Preliminary remarks on measurement methods:

[0135] elasticity

[0136] To determine the extensibility of a comparative example as well as various multilayer films according to the invention in the form of tubular films (inner and outer tubular films) and in particular also the lining tubes according to the invention themselves, inflation tests were carried out.

[0137] In the case of a multilayer film that is not in the form of a tubular film, but rather, for example, a flat film, it is sealed into a tube in order to subsequently determine its elasticity. The tests within the scope of the invention were carried out both on tubular films and on finished lining tubes (or insert tubes or pipe liners).

[0138] For preparation, a 5-meter-long tubular film with a circumference of approximately 800 mm to 1200 mm is hermetically sealed at both ends with two metal discs (so-called packers) of a suitable diameter. To achieve airtightness, tension straps and standard duct tape were used, as is common practice in such inflation tests. Compressed air is introduced into the tubular film through a valve in one of the packers until it bursts. Before bursting, tears in the inner layers of the film are visible; these are referred to as "splices." A small, localized bubble often forms within the multi-layered film, which then, with further inflation, leads to a tear in the film and the bursting of the tubular film.The maximum elongation (expressed as a percentage) is determined by measuring the outer circumference of the tubular film at its largest point until it bursts and comparing it to the initial tubular diameter, using the following formula:

[0139] Maximum elasticity = [(hose diameter after inflation / initial hose diameter before inflation) - 1] • 100

[0140] The same formula applies to the "film splice", i.e. the first noticeable tear of a layer of the hose film (without the entire hose being affected):

[0141] "Splice" = [(hose diameter after inflation and first visible layer tear / initial hose diameter before inflation) - 1] • 100

[0142] What applies to a tubular film according to the formula above naturally also applies to the entire lining tube. Here, too, the elongation until bursting was determined using the measurement method described above. However, a splice was only visible in the outer tube film, as the inner tube film was no longer visible from the outside (meaning from outside the lining tube) due to the mostly opaque outer film and the resin-impregnated carrier material.

[0143]

[0144] with the foils

[0145] To determine and compare the homogeneity of the respective films, for example, to qualitatively or indirectly detect possible micro-holes, the following procedure was performed: The film under investigation was cut into square pieces measuring 10 cm x 10 cm. Two such pieces of film were first welded together on their polyol efin side, i.e., the PE side, which provides a very good seal, to form a "film pocket." Those skilled in the art are familiar with the welding conditions for standard sealing equipment (for example, sealing temperature 120°C, sealing pressure 1 bar, sealing time 1 s). The two pieces of film were placed on top of each other and welded firmly and completely tightly together along their left edge, right edge, and underside. This was achieved using a standard sealing device with a sealing bar 1 cm wide and 15 cm long.From the still open top of this (three-point sealed) foil pouch, approximately 5 g of toluene are poured in (preferably using a pipette). This toluene serves as a chemical replacement for the styrene used in the reactive resins. The open top of the foil pouch is then sealed, so that the liquid, in the form of approximately 5 g of toluene, is now completely enclosed by the foil. This is crucial.

[0146] Meticulous care is taken to ensure that the surface area of ​​each foil pouch, containing approximately 5 g of toluene, is largely or practically identical. Furthermore, every effort is made to fill and enclose approximately 5 g of toluene in each pouch as precisely as possible. After the foil pouch is completely sealed, the amount of toluene is weighed to four decimal places using a Gram FS 120 laboratory / analytical balance.

[0147] The sealed foil pouches filled with toluene were then stored under standard climate conditions for an extended period. After six months and again after one year, the sealed foil pouches were weighed once more to determine if and how much toluene had escaped. This provides information about the impermeability of the tested films, i.e., their barrier effect against organic solvents such as toluene or monomers such as styrene. The higher the amount of toluene that escaped, the less permeable the film. The inventors here suspect that the cause of this is the presence of so-called "micro-holes," particularly in the polyamide layer, through which both solvents and monomers can escape through the film. Therefore, the more toluene remains in the sealed foil pouches after six months or a year, the more homogeneous and dense the polyamide layer of the tested films is.

[0148] The weight loss of toluene is given as a percentage, based on the initial weight of the toluene (approx. 5 g each).

[0149] The result is cross-checked using the other microscopic measurement methods listed below.

[0150] The homogeneity of the respective films (on their outer PA side) could be determined by analyzing the surface texture using the AFM method (Atomic force microscopy).

[0151] An atomic force microscope (AFM) is a high-resolution microscope that relies on measuring the interaction forces between a tiny tip and a sample. It is used in various scientific, industrial, and research applications.

[0152] Here are some important uses for an atomic force microscope:

[0153] 1. Surface imaging. The AFM enables high-resolution imaging of surfaces at the nanoscale. It can capture the structures and topographies of materials with very high resolution.

[0154] 2. Material characterization. AFM is used to characterize material properties, including hardness, elasticity, and adhesion. This is particularly important in materials science and engineering.

[0155] 3. Surface roughness measurement. The AFM enables the precise measurement of the surface roughness of materials. This is important in applications such as the manufacture of optical components and electronic devices.

[0156] 4. 'Crass spectroscopy'. The AFM enables the measurement of the interaction forces between the tip and the sample. This allows the investigation of force properties and molecular bonds at the nanoscale.

[0157] Overall, due to its high resolution and versatile applications, the atomic force microscope is an extremely powerful instrument in various scientific disciplines and industries.

[0158] The measurements were performed on a PHYWE Compact AFM atomic force microscope.

[0159] Furthermore, the films according to the invention, as well as the reference films (from the prior art), were examined, particularly on the polyamide outer surface, using scanning electron microscopy (SEM), which also allows the determination of the surface properties. In particular, so-called "micro-holes" can be detected very effectively in this way, should they be present.

[0160] A Hitachi TM4000Plus-II scanning electron microscope was used for these investigations. Example 1:

[0161] Chemical characterization of the raw materials used

[0162] Commercially available polyamides (brand names in parentheses) from the following companies can be used for at least one PA layer: BASF (Ultramid), Lanxess (Durethan), DuPont (Zytel), DSM Engineering Plastics (Akulon, Stanyl), EMS-Chemie (Grilamid, Grivory, Grilon), Evonik (Trogamid), Radici (Radilon, Radiflam, Raditer, Heraform, Heraflex), Rhodia (Technyl, Stabamid), UBE, DSM (Novamid), and Atofina (Rilsan). In the examples presented below, Durethan C38 F (Lanxess) is used as the polyamide layer.

[0163] In the films according to the invention, this PA layer made of Durethan C38 is mixed with a polyblock amide that contains both soft elastic segments and stiff, inflexible, hard polyamide blocks.

[0164] In this invention, VESTAMID® E - Polyetherblockamide PEBA from Evonik is used as a polyblock amide containing both soft elastic segments and stiff, inflexible, hard polyamide blocks (abbreviated as PEBA).

[0165] Specifically, the extrusion-compatible VESTAMID® E40-S3 was used in the examples. This is characterized by a very low modulus of elasticity or tensile modulus (in the dry state; according to ISO 527; below 100 MPa) and by an extremely low glass transition temperature Tg (in the dry state of -60°C).

[0166] A typical adhesion promoter that can be used is, for example, Admer NF 498 E, which is a maleic anhydride-modified LDPE from Mitsui. Another typical adhesion promoter that can be used is, for example, Admer QB 520 E, which is also a maleic anhydride-modified homo-PP (homo-polypropylene) from Mitsui.

[0167] Typical polyolefins that can be used include, for example, Lupolen 2420 F, an LDPE from LyondellBasell Polymers, and Exceed 1327 CA from ExxonMobil Chemical Company, an ethylene copolymer produced by metallocene catalysis, in whose polymerization, in addition to ethylene, hexene is used as a further co-monomer. The Exceed 1327 CA used in the examples according to the invention is designated or abbreviated as mLLDPE.

[0168] Example 2:

[0169]

[0170] of the multilayer films:

[0171] The multilayer film of comparative example 1 (VI) consists of three layers. This is comparative example 5 from DE 10 2009 041 841 Al. This film is used as an inner lining film for the production of lining hoses.

[0172] The multilayer films (inner tubing films) according to the invention of Examples 1-2 (Bl-B2) also each consist of three layers.

[0173] The film used as the outer tubular film in Example 3, however, is a 5-layer film. For reference, i.e., as a comparative example V2, the outer tubular film described in Example 1 of DE 102009041 841 Al is used.

[0174] The individual layers of the multilayer films are directly adjacent to each other in the order in which they are listed below.

[0175] The multilayer films of comparison examples VI and V2 as well as examples 1-3 (B1-B3) were each produced as tubular films by blown film co-extrusion.

[0176] 3: on foils: ei VI (inner hose foil) and V2 (outer hose foil) and Bl and B2 (inner hose foils) and B3 (outer hose foil)

[0177]

[0178] Example VI (3-layer film): This is comparative example 5 from DE 102009041 841 Al. This film is used as an inner film for hoses in the manufacture of lining hoses.

[0179] Example V2 (5-layer film):

[0180] As a reference, i.e. as a comparative example V2, the outer film of the hose is used, which is described in Example 1 in DE 102009041 841 Al.

[0181] Example according to the invention Bl (3-layer film):

[0182] Inner tube film structure with 60% mLLDPE in layer (3) and 10% PEBA in the PA layer (1) Layer composition Percentage in thickness in pm

[0183] Number shift in

[0184] % by weight

[0185] (1) • Durethan C38 F • 90 40

[0186] (At • PEBA • 10

[0187] Pipe liner

[0188] towards

[0189] canal wall

[0190] or to the Harz Mountains

[0191] directed)

[0192] (2) • Admer NF 498E • 100 15

[0193] (3) • LDPE: Lupolene • 40 145

[0194] At 2420 F • 60

[0195] Hose liner • mLLDPE

[0196] for the

[0197] flowing

[0198] medium

[0199] directed

[0200] (Channel interior)

[0201] Total thickness:

[0202]

[0203] 200 pm

[0204] Inventive example B2 (3-layer film):

[0205] Inner tube film structure with 100% mLLDPE in layer (3) and 15% PEBA in the PA layer (1)

[0206] Layer composition, proportion in thickness (pm)

[0207] Number shift in

[0208] % by weight

[0209] (1) • Durethan C38 F • 85 40

[0210] (At • PEBA • 15

[0211] Pipe liner

[0212] towards

[0213] canal wall

[0214] or to the Harz Mountains

[0215] directed)

[0216] (2) • Admer NF 498E • 100 15

[0217]

[0218] (3) • mLLDPE • 100 145

[0219] At the

[0220] Pipe liner

[0221] for the

[0222] flowing

[0223] medium

[0224] directed

[0225] (Channel interior)

[0226] Total thickness:

[0227]

[0228] 200 pm

[0229] Example B3 according to the invention:

[0230] Construction: Outer tube film with 97% mLLDPE in layers (1) and (5) and with 15% PEBA in the PA layer (3)

[0231] Layer composition, proportion in thickness (pm)

[0232] Number shift in

[0233] % by weight

[0234] (1) • mLLDPE • 97 65

[0235] • Batch 2 from DE 102009 • 3

[0236] 041 841 Al

[0237] (2) • Admer NF 498E • 97 20

[0238] • Batch 1 from DE 102009 • 3

[0239] 041 841 Al

[0240] (3) • PA • 90 30

[0241] • PEBA • 10

[0242] (4) • Admer NF 498E • 97 20

[0243] • Batch 1 from DE 102009 • 3

[0244] 041 841 Al

[0245] (5) • mLLDPE • 97 65

[0246] • Batch 2 from DE 102009 • 3

[0247] 041 841 Al

[0248] SymmeTotal thickness:

[0249] 200 pm

[0250] trischer

[0251] Construction

[0252]

[0253] Results from the inflation tests:

[0254] Example / Splice [%] Elongation [%] up to

[0255] Comparative example game to burst

[0256] Page 55 223

[0257] B2 68 253

[0258] B3 43 203

[0259] VI 20 95

[0260] V2 16 81

[0261]

[0262] Observations and evaluations of the inflation tests:

[0263] Comparing the inventive examples of inner tubing film Bl and B2 with the values ​​of the prior art reference film from comparative example VI, where all films have a total thickness of 200 pm, it is immediately apparent what an enormously positive effect the use of mLLDPE in the polyolefin layer at a concentration of at least 30 wt.% and the addition of PEBA to the polyamide layer has with regard to splicing and elongation to bursting. These values ​​have practically tripled in the films according to the invention!

[0264] Comparing the inventive example of tubular outer film B3 with the values ​​of the prior art reference film from comparative example V2, where all films again have a total thickness of 200 pm, it becomes immediately apparent what an enormously positive effect the use of mLLDPE in the polyolefin layer at a concentration of at least 30 wt.% (in example 3, the mLLDPE is present at a concentration of 97 wt.% in layers 1 and 5) and the addition of PEBA to the polyamide layer have with regard to splicing and elongation to bursting. These values ​​have practically tripled for the inventive film with respect to splicing compared to reference V2, and for elongation to bursting, they have increased from 81% in V2 to 203% in example B3!

[0265] Feel of the foils at -18°C

[0266] The foils from the examples and the comparison examples were stored for one day at -18°C and then subjected to a manual, i.e., haptic, test. This involved determining how the foils felt in the hand. This allowed for a simple assessment of their stiffness or softness. The following results were obtained:

[0267] Example / Temperature in °C for assessing the foil

[0268] Compare to games

[0269] Storage 1 day

[0270] Bl -18 Soft, supple

[0271] B2-18 Very soft and very supple B3-18 Soft, supple

[0272] VI -18 Firm, hard, “wrinkled”

[0273] V2-18 Firm, hard, "wrinkled", brittle

[0274]

[0275] This shows that the films according to the invention in examples B 1 to B3 – regardless of whether they are inner or outer tubing films – remain soft and supple even at a temperature of -18°C. The films according to the invention therefore do not tend to become brittle even at very low temperatures far below freezing.

[0276] Thus, the films according to the invention retain their extremely high elongation capacity and significantly reduced tendency to splice (i.e., a splice only occurs at significantly higher elongation) even at temperatures of -18°C, whereas conventional films known in the prior art fail long ago.

[0277] Results from the investigations using AFM

[0278] Using the AFM method described above, the films from the examples and the comparison examples were characterized on the outer PA side with regard to the surface properties on both sides.

[0279] Since the outer films of the hoses do not have a PA outer layer, they were not tested.

[0280] Example / Result regarding surface quality using comparison of AFM measurements on the PA side

[0281] Homogeneous, smooth surface, no holes or craters, slightly wavy structure

[0282] B2 Homogeneous, smooth surface, no holes or craters, flat structure

[0283] VI Slightly inhomogeneous surface, small craters are visible, possibly also micro-holes

[0284]

[0285] An almost analogous result was found when examining the PA side of the foils using scanning electron microscopy (SEM), as follows:

[0286] Example / Result regarding surface quality using comparison of SEM measurements on the PA side

[0287] Homogeneous, smooth surface, no holes or craters, flat structure

[0288] B2 Homogeneous, smooth surface, no holes or craters, flat structure

[0289] VI “Unsteady”, inhomogeneous surface with recognizable “mountains” and valleys”, occasionally

[0290] Small craters are visible; these may also be micro-holes.

[0291]

[0292] The results of the AFM and SEM measurements clearly demonstrate the advantages of the inventive inner tubing films of Examples B1 and B2 compared to the reference film from Comparative Example VI. This confirmed, indeed proved, the inventors' hypothesis that the addition of PEBA to the PA layer leads to a kind of "self-healing" of the surface and that, due to the high flexibility of the combination of PA with the polyblock amide, which contains both soft elastic segments and stiff, inflexible, hard polyamide blocks, any formation of craters or micro-holes is prevented. This was a completely unexpected result within the scope of this invention.

[0293] Determination of the tightness of the films (by detecting the escape of toluene from films formed into "pockets" and tightly sealed)

[0294] The test described above yielded the following results:

[0295] Example / Weight loss Weight loss

[0296] Comparison example after 12 months in %

[0297] after 6 months in %

[0298] Bl 0.03 0.05

[0299] B2 0.01 0.02

[0300] B3 0.01 0.03

[0301] VI 0.52 1.02

[0302]

[0303] V2 0.33 0.89

[0304]

[0305] These measurements also clearly show that the films according to the invention in Examples Bl to B3 are significantly more resistant to the escape of monomers or organic solvents (here, toluene) than the reference films in Examples V1 and V2. The films according to the invention in Examples Bl to B3 thus possess a considerably higher barrier against monomers, oils, and solvents compared to the reference films. The film from V2 is even slightly more dense than the film from VI, presumably because in film V2 the polyamide layer (PA) is located on the inside and is therefore protected on both sides by polyolefin layers, thus largely preventing the PA layer from being affected by the weather.An explanation for the test results has already been given several times above: Since the films of examples Bl, B2 and B3 do not have micro-holes because their at least one polyamide layer “heals itself” through the addition of the polyblock amide, which contains both soft elastic segments and stiff, inflexible, hard polyamide blocks, this effect is expressed (macroscopically) in significantly better barrier values ​​of these films according to the invention.

[0306] The multilayer films according to the invention can be used not only for sewer rehabilitation using the described UV curing or curing with short-wave visible light, but also in pipe rehabilitation systems in which the liner (comprising the multilayer film according to the invention) is thermally cured or the inversion method is used. The multilayer film according to the invention can also be used in the form of a preliner or a support and calibration film.

[0307] For the purposes of this invention, a preliner is understood to be a film, preferably in the form of a foil tube or a flat film sealed to form a tube, which is inserted between the wall of the sewer to be rehabilitated and the pipe liner. As a preliner, the film fulfills a number of functions, such as preventing the resin from adhering to the sewer wall and preventing contact between dirt and water and the uncured resin. Furthermore, the preliner film also prevents resin from escaping the sewer rehabilitation system and from contaminating the soil and groundwater. The preliner film also protects the inlets from penetrating excess resin, thus preventing the formation of resin plugs and blockages.

[0308] The use of the multilayer films according to the invention as a preliner is similar to their function as a sliding film for the pipe liner to be inserted. In this case, low coefficients of friction between the sliding film and the outer film of the pipe liner are crucial.

[0309] Example 4:

[0310] Testing the elasticity of the lining tubes using the inflation test:

[0311] Lining tubes were produced using the films of the inventive examples Bl and B2 (inner tube films) and B3 (outer tube film) as well as the comparative examples VI (inner tube film) and V2 (outer tube film) using the so-called “winding process”, which is described in detail, for example, in WO-A 95 / 04646.

[0312] The measurement of the elongation was carried out exactly as with the bare foils, as described above.

[0313] The same formula applies here:

[0314] Maximum elongation of the lining tube = [(tube diameter after inflation / initial tube diameter before inflation) - 1] • 100 Due to the fact that a complete lining tube was subjected to the inflation test, detecting splices in the respective films was extremely difficult.

[0315] Therefore, in this case, only the elongation until the lining hose "bursts" could actually be determined. This also refers to the point at which the outer film of the hose begins to tear, allowing the compressed air used to inflate the lining hose to escape.

[0316] Within the framework of the test setups TI to T4 presented below and the comparative test setup VT5, the expansion of the lining tube was also carried out in defined "stages" (sections) of 7%, 25%, 44% and 68%. At these measuring points or "stages", the suitability was then assessed as "passed" (no bursting) or "failed" (burst).

[0317] Example 5:

[0318]

[0319] for the rehabilitation of damaged canals:

[0320] A flattened inner liner, 420 mm wide and 20 m long, is first stripped onto a standard dome described in WO-A 95 / 04646. The liner is then unwound and successively wrapped with resin-impregnated fiber tapes, 630 mm wide, such that the resin-impregnated carrier layer has a total thickness of 6.3 mm around the inner liner tube at every point. Before impregnation with the reactive resin, the fiber tapes had a basis weight of 740 g / m². After impregnation, the basis weight increased to 1450 g / m².

[0321] A standard UP resin, familiar to professionals, was used for impregnation.

[0322] When winding the resin-impregnated fiber tapes of the lining tube according to the invention, which is preferred within the scope of this invention, it is taken into account that the wall thickness of the laminate decreases accordingly due to the high radial elongation, so that the material thickness of the helically wound fiber tapes has been increased by a corresponding amount in order to produce the layer of fiber material with a corresponding excess, which ensures the required strength in the finished product after expansion and curing.

[0323] The inner film tube, thus produced by wrapping it with resin-impregnated fiber tapes and applying longitudinal tension bands, is then inserted between two UV- and light-tight (according to the invention) outer films (flat width 570 mm, thickness 200 µm) which are in the form of flat films. These outer films are then sealed to form a tube by welding, whereby an outer film of the same width of 570 mm is fed from above and another outer film of the same width of 570 mm is fed from below to form the outer tube. The inner film, wrapped with the resin-impregnated fiber tapes, is located between the two outer films, which are in the form of flat films.

[0324] 15 m of the liner tube produced in this way are used for the subsequent horizontal inflation tests to various dimensions. These 15 m are taken from the middle of the 20 m long liner tube.

[0325] In the horizontal inflation test, the lining tube is drawn through 1.5 m long pipe sections with the dimensions (i.e., diameters) (1) 300 mm, (2) 350 mm, and (3) 400 mm. After sealing the ends of the lining tube using packers familiar to those skilled in the art, the following structure is obtained in the following dimensions:

[0326] (1) - (2) - (3) - (2) - (1).

[0327] In these inflation tests, the liner tube was gradually expanded to the required dimensions under an internal pressure of up to 400 mbar. Additionally, a liner tube is manufactured by stripping a flat inner liner film, 920 mm wide and 15 m long, onto the dome. The film is then unwound and successively wrapped with resin-impregnated fiber tapes, 840 mm wide, such that the total thickness of the resin-impregnated carrier layer around the inner liner tube is 9.8 mm. Before impregnation with reactive resin, the (glass) fiber tapes had a basis weight of 740 g / m². After impregnation, the basis weight increased to 1450 g / m².

[0328] A conventional unsaturated polyurethane (UP) resin, familiar to those skilled in the art, was used for impregnation. The resulting inner film tube, wrapped with resin-impregnated fiber tapes, is then inserted into two UV- and light-tight (according to the invention) outer films (flat width 1150 mm, thickness 200 µm) which are flat films. The outer films are then sealed by welding to form a tube.

[0329] Three meters of the resulting lining hose are used for the subsequent vertical inflation test to DN 1000 with a conical transition. These three meters are taken from the 15-meter-long lining hose.

[0330] In the vertical inflation test, an additional inner foil tube according to the invention, which has a flat width of 920 mm and is closed at one end with a knot or cable tie, is inserted into the lining tube, creating a foil bag that is preferably approximately 10% longer than the finished lining tube. The lining tube is then closed at its lower end with a seam, sealed at its upper end together with the inserted air bag using a packer, and lowered into a vertical test mold to its base using a crane. The interior of the air bag is pressurized with compressed air from an external compressed air source. This causes the additional inner foil tube (air bag) to expand and initially conform to the lining tube and its inner foil tube.In this inflation test, the lining hose was gradually expanded to the required dimensions with an internal pressure of up to 500 mbar. Results from the inflation tests on lining hoses for the rehabilitation of sewers with different diameters (test setups according to the invention TI to T4, comparative test setup VT5):

[0331] Inner film of the hose, outer film

[0332] Test setup: elasticity

[0333] Bl and B2 B3

[0334] Lining hose

[0335] Material thickness Flat width Flat width 7% 25% 44% 68% TI 200pm 420 570 passed passed passed passed T2 150pm 420 570 passed passed passed passed T3 170pm 420 570 passed passed passed passed ___ ___ ___

[0336]

[0337] T4 120pm 920 1150 passed

[0338] Inner film of the hose, outer film

[0339] Elasticity test setup lining hose VI V2

[0340] Material thickness Flat width Flat width 68%

[0341]

[0342] VT5 200pm 920 1150 Failed: failed

[0343] The results with the lining tubes according to the invention in test setups TI to T4 demonstrate their outstanding suitability for the rehabilitation of damaged shafts or channels, as an elongation of at least 68% could be achieved. However, this was still not the end of the possibilities.

[0344] If the lining tubes of the test setups TI to T4 according to the invention had not been adjusted to a successful elongation of 68% (which was already more than sufficient!), an even higher elongation could certainly have been achieved (the inventors even suspect an elongation well over 100%).

[0345] In contrast, the non-inventive lining tube of the comparative test setup VT5 (with the non-inventive films) failed at an elongation of 68%. This lining tube from VT5 burst much earlier.

[0346] As the inventors further discovered, the tubular films according to the invention surprisingly result in an extremely stretchable composite film in which the polyamide layer, due to the addition of the polyblock amide, which contains both soft elastic segments and stiff, inflexible, hard polyamide blocks, remains intact as a barrier layer even when stretched by, for example, more than 65%. Because the PA barrier layer with the polyblock amide, which contains both soft elastic segments and stiff, inflexible, hard polyamide blocks, does not tear locally when stretched by, for example, more than 65%, the polyolefin, in particular the m-LLDPE, is protected by the PA barrier layer and not decomposed by the styrene, which is contained in the reaction resin as a solvent.This unexpected effect, discovered by the applicant, of stabilizing the highly elastic m-LLDPE layer with the applied PA containing the polyblock amide, which includes both soft elastic segments and stiff, inflexible, hard polyamide blocks, results in a composite film that prevents the escape of styrene into the interior of the lining tube with surprisingly high reliability, even at high elongations of over 65%.

[0347] As the inventors further discovered through experiments, a pure m-LLDPE film without the applied PA layer containing the polyblock amide, which includes both soft elastic segments and stiff, inflexible, hard polyamide blocks, is attacked and damaged much more quickly by the styrene in the reaction resin than a pure PE film, so that even in m-LLDPE films with a thickness of more than 100 micrometers, the styrene is no longer effectively retained by the film.

[0348] Therefore, the highest stability of the at least one polyamide layer in the films according to the invention is crucial, which is ensured (only) by the addition of the polyblock amide, which contains both soft elastic segments and stiff, inflexible, hard polyamide blocks, even under extremely high elongations.

[0349] According to a further aspect of the invention, the tubular layer of fiber material impregnated with the curable reaction resin comprises at least one helically overlapping fiber band or at least one fiber band extending longitudinally along the lining tube, overlapping at its longitudinal edges, which is wrapped around the barrier layer and whose inner surface rests directly against the barrier layer. This offers the advantage that the fiber band layer can be produced by multi-layered, overlapping helical winding or layering of several fiber bands of any desired thickness without impairing radial expansion.

[0350] In the preferred embodiment of the invention, the inner foil tube is permeable to UV light, and the reaction resin is a resin that can be cured by irradiation with UV light. Alternatively, it can be provided that the reaction resin is a resin that can be cured by heat, and the (inventive) inner foil tube 10 is configured to be exposed to heated water, hot steam, or heated air for curing the resin.

[0351] To improve the so-called calibrability of the lining tube according to the invention and to prevent the escape of styrene into the surrounding soil, the tubular layer of fiber material is advantageously preferably surrounded by a (according to the invention) UV- and light-tight outer film tube formed from a composite film of at least three layers, comprising the following layers: At least one further outer first layer, which consists of a metallocene linear low-density polyethylene (m-LLDPE) or preferably contains such a material to at least 30 wt.%,

[0352] at least one adhesion promoter layer and

[0353] at least one barrier layer consisting of polyamide (PA), which is a polyblock amide containing both soft elastic segments and stiff, inflexible, hard polyamide blocks. In the embodiment described last, a layer of nonwoven material, in particular a polyester nonwoven, is preferably laminated onto the inside of the inner protective layer made of at least 30 wt.% m-LLDPE, facing the tubular layer of fiber material. After the curing of the reaction resin, this leads to an intimate bond between the outer protective layer made of m-LLDPE and the layer of fiber material, thereby making the lining tube mechanically very resistant.As the inventors have discovered in this context, it is also surprisingly possible to laminate nonwoven polyester material, which can have a thickness of more than 20 pm and less than 500 pm, onto the protective layer made of m-LLDPE, which has previously only been known in connection with the blown film extrusion of PE-PA-PE films from conventional polyethylene (LDPE), in which the nonwoven material is melted onto the still liquid heated polyethylene.

[0354] As the inventors further discovered, the nonwoven layer expands easily during the expansion of the lining tube, despite the very high elasticity of the outer film of the tube according to the invention, and remains as a closed, homogeneous layer across its entire surface after the lining tube has expanded and the reaction resin has cured, without being affected by the styrene. This results in a mechanically high-strength bond between the outer film tube (according to the invention) and the fiber material, which advantageously increases the overall mechanical strength of the installed lining tube according to the invention.

[0355] To counteract mechanical damage to the lining tube according to the invention when it is pulled into a substantially horizontal channel, in the preferred embodiment of the lining tube a further outer film tube made of a reinforced tensile-resistant material, in particular a fabric-reinforced plastic film, such as a truck tarpaulin, can be arranged around the outer film tube to absorb axial tensile forces, which tears open along a predetermined tear point when the lining tube expands and allows radial expansion despite the low elasticity of the fabric material, so that the lining tube according to the invention can expand radially to such an extent that it lies completely against the inner wall of the channel.

[0356] The invention is described below with reference to the drawings, using the example of a sewer pipe with two diameter sections and a manhole, without limiting it in any way.

[0357] The drawings show:

[0358] Fig. 1 shows a schematic cross-sectional view through the wall structure of an exemplary lining tube according to the invention, with an enlarged representation of the different layers.

[0359] Fig. 2 shows a schematic representation of a preferred embodiment of a winding device with a lining tube according to the invention, during the winding process.

[0360] Fig. 3 shows a schematic representation of a defective sewer pipe with a first pipe section of smaller diameter and a second pipe section of larger diameter, into which a lining hose according to the invention has been inserted. Fig. 4 shows a schematic representation of a defective manhole after the insertion of a lining hose according to the invention, into which a further airtight calibration bag is inserted, which is closed at its first lower end by a knot.

[0361] Fig. 5 shows the manhole of Fig. 4 after the expansion and hardening of the lining hose.

[0362] As shown in Figures 1 and 2, a lining hose 1 for the rehabilitation of a defective sewer pipe 100 shown in Figure 3, which has a first pipe section 110 with a first diameter and a second pipe section 120 adjoining it with an enlarged diameter, comprises an inner foil hose 10 and a radially expandable layer of fiber material 20 arranged around it, which is impregnated with a curable reaction resin.

[0363] The inner film tube 10 shown in cross-section in Fig. 1 is formed from a composite film comprising (at least) a first inner layer 10.1 consisting of at least 30 wt.% m-LLDPE and (at least) a barrier layer 10.3 arranged on this, made of polyamide, which is a polyblock amide containing both soft elastic segments and stiff, inflexible, hard polyamide blocks, which are connected to each other via (at least) a bonding layer 10.2, in particular an adhesion promoter.

[0364] The lining tube according to the invention is characterized with respect to the inner tube film used in the invention in that the plastic material of the (at least) one layer 10.1 is a metallocene linear low-density polyethylene (m-LLDPE) or contains such a material to at least 30 wt.%, and that the at least one layer 10.1 has a thickness of 10 to 500 g / m², preferably 20 to 400 g / m², particularly preferably 30 to 300 g / m², and most preferably 40 to 200 g / m². The at least one PA layer 10.3 has a thickness of at least 5 to 200 g / m², preferably 15 to 90 g / m², and particularly preferably 20 to 60 g / m².

[0365] The at least one PA layer 10.3 contains a polyblock amide that has both soft elastic segments and stiff, inflexible, hard polyamide blocks, and is directly adjacent to the layer of fiber material 20. The bonding layer 10.2, i.e., the at least one adhesion promoter layer (HV), preferably has a thickness of 1 to 50, more preferably of 2 to 20 pm, wherein an adhesion promoter known from the prior art, such as a maleic anhydride-grafted polymer based on LDPE or LLDPE, which is marketed by Mitsui Chemicals Europe GmbH for the adhesion of polyamide to polyethylene plastic films, e.g. under the trade name "Admer™ NF 498E", can be used.

[0366] The joining of the layers 10.1, 10.2 and 10.3 of the composite film, which are present at least once in the tubular film (here inner film) according to the invention, is preferably carried out by blown film coextrusion of m-LLDPE, the adhesion promoter HV and the PA.

[0367] As can be further seen from Fig. 1, in the preferred embodiment of the lining tube 1, an outer film tube 40 according to the invention is arranged around the layer of fiber material 20, which - like the inner film of the tube - is preferably formed from a composite film of at least three layers, comprising the following layers:

[0368] At least one outer first layer 40.1 consisting of m-LLDPE or containing such in the layer to at least 30 wt.%,

[0369] A barrier layer 40.3, consisting of or containing PA, is arranged on the inside of the first layer 40.1 and connected to it via at least one further bonding layer 40.2 of an adhesion promoter, and next to it a polyblock amide comprising both soft elastic segments and stiff, inflexible, hard polyamide blocks. Furthermore, the outer film of the tube according to the invention can be connected after layer 40.3 again via a further adhesion promoter layer 40.4 to finally a further polyol efin layer 40.5.

[0370] That is even preferred.

[0371] On the inside of the inner protective layer 40.5 made of polyolefin, in particular polyethylene with at least 30 wt.% mLLDPE, i.e., on the side facing the center of the lining tube 1 (in the direction of the medium subsequently flowing through the rehabilitated channel), a layer 40.6 made of nonwoven material, in particular a PE, PP, or polyester nonwoven, or also a glass nonwoven, is laminated to the tubular layer of fiber material 20. This nonwoven material has a thickness in the range of 20 to 1000 pm, preferably 30 to 500 pm. As can be further seen from the illustration in Fig. 2, in the embodiments of the lining tube 1 described above, at least one longitudinal tension band 30 is preferably arranged on the layer of fiber material 20, extending in the longitudinal direction of the lining tube 1. The longitudinal tension band 30, which is shown in Fig.

[0372] 1, which is not shown for illustrative reasons, preferably comprises continuous glass fibers or glass fiber rovings, which preferably run over the entire length of the lining hose 1 and absorb the axial forces when the lining hose 1 is pulled into a defective sewer pipe 100 to be rehabilitated, for example by means of a pull rope.

[0373] As can be further seen from the illustration in Fig. 1, a further outer film tube 50 made of a reinforced tensile-strength material, in particular a fabric-reinforced plastic film, such as a truck tarpaulin, can be arranged around the (preferably invention-specific) outer film tube 40. This second outer film tube is preferably used when pulling the lining tube into a horizontally running sewer pipe. To allow radial expansion of the further outer film tube 50, it has a predetermined tear point 52 extending in the longitudinal direction of the lining tube 1. This tear point can be provided, for example, by an adhesive section, in particular an adhesive tape, connecting the two longitudinal edge sections of the fabric-reinforced plastic material. This adhesive tape yields or tears when the lining tube 1 is expanded by means of compressed air, so that the inner outer film tube 40 can expand radially without restriction.

[0374] The outer film tube 40 (or the outer film of the tube) can also be designed in such a manner, provided that it is not designed to be particularly stretchable according to the invention. In this case, too, as the examples above have shown in the context of the inflation tests on the finished lining tube according to the invention, either an expansion joint or a predetermined breaking point is required.

[0375] The invention further relates to a method for lining a defective sewer pipe 100, which is described in more detail below with reference to the illustration in Fig. 3. The sewer pipe 100 comprises a first pipe section 110 with a first diameter and a second pipe section 120 adjoining it with a larger diameter. To repair the defective sewer pipe 100, a lining tube 1 described above is inserted into the defective sewer pipe 100, and both ends of the lining tube 1 are sealed with a packer 200. Subsequently, the lining tube 1 is expanded by introducing a pressure medium, in particular compressed air from a compressed air source 6, into the inner foil tube 10. This causes the lining tube 1 to conform directly to the inner wall of the first pipe section 110.In the second pipe section 120 with an enlarged diameter, the inner foil tube 10 expands radially inside the channel pipe 100, whereby the fiber material of layer 20 also expands radially by shifting the helically wound fiber band(s) 22.

[0376] In a final process step, the reaction resin in layer 20 is cured in a known manner by introducing and drawing through the interior of the inner foil tube 10 a radiation source not shown in detail.

[0377] The method described above can be used analogously for the rehabilitation of sewer pipes 100 with a constant cross-section, the diameter of which lies between the defined nominal diameter of the lining hose 1 and the maximum diameter to which the inner foil hose 10 and the outer foil hose arranged around it can be expanded. In practice, the range to which the diameter of the lining hose 1 can be expanded is a maximum of 160% to 200% of the nominal diameter of the hose. Thus, a lining hose with a nominal diameter DN of 30 cm (DN 300) can, for example, be used to line sewer pipes with diameters between approximately 33 cm and 90 cm (DN 900), assuming that a minimum expansion of 10% is required to reliably expand the lining hose 1 and fully conform it to the inner wall of the sewer 100.

[0378] This allows for a significant reduction in the number of diameters that need to be kept in stock, resulting in a considerable decrease in storage costs and logistics effort. In other words, since only a few basic sizes of lining tubes need to be manufactured and kept in stock, the considerable setup times required to change the winding devices from one diameter to another are also reduced. Furthermore, this increases the flexibility of the lining tube or pipe liner manufacturer – in particular, customer requests can be handled much faster than with competitors, thus gaining a significant market advantage.

[0379] According to a further idea underlying the invention, the lining hoses 1 according to the invention can also be used to line a defective manhole 400, which is shown in Figs. 4 and 5.

[0380] For this purpose, the first end of the lining hose 1, which is to be inserted into the manhole 400, is first closed, in particular by sewing, clamping, or gluing along a transverse seam 405, as indicated in Fig. 4. The lining hose 1 to be inserted into the manhole 400 can, for example, be cut from a longer lining hose 1 supplied by the meter as a section with a length essentially corresponding to the manhole depth. This is economically advantageous compared to individual production if, for example, several manholes 400 in a street are to be rehabilitated one after the other.

[0381] Subsequently, the second end of the lining hose 1 is attached to a packer 200 in a known manner, e.g. by means of a tension strap 210, the packer is lifted by a lifting device, and the first end of the lining hose 1, which is closed by the transverse seam 405, is lowered into the manhole 400 to be rehabilitated, as shown in Fig.

[0382] 4 is indicated. The insertion of the lining hose 1 by the lifting device (not shown in detail) into the opened manhole 400 is advantageously carried out in such a way that the transverse seam 405 extends along the channel 406 at the bottom of the manhole 400, which makes it possible to line the bottom of the manhole 400, the so-called berm, in one operation.

[0383] A calibration bag 410, preferably closed at one end by a knot 420, is then inserted into the inner foil tube 10 from above, and its open upper end is connected airtight to the packer 200. This can be done, for example, by folding the upper edge of the calibration bag 410 over the edge of the packer 200 and then closing the packer 200 with a cover 202, indicated in Fig. 5, through which the pressurized gas is supplied from the pressurized gas source 6. Subsequently, the calibration bag 410 is expanded by introducing a pressurized medium, in particular compressed air, into its interior, such that the lining tube 1, i.e., the inner foil tube 10 according to the invention and the layer 20 of fiber material arranged thereon, as well as any necessary additional material, expands.An outer film tube 40 (according to the invention) surrounding the outside of the lining tube 1 expands radially and is applied to the inner wall of the manhole 400, as indicated in Fig. 5. In this process, the overlapping, helically wound, or alternatively, overlapping layers 20 of fibrous material shift relative to one another such that the outer diameter of the lining tube 1 in the lower expanded part of the manhole 400 and in the upper, access-side part adapts to the respective inner diameter of the manhole 400. In contrast, the inner film tube 10 according to the invention, and also the preferably used outer film tube 40 according to the invention, expand locally in the respective areas of the manhole 400 due to their exceptionally high elasticity, corresponding to the respective diameter and a reduction in film thickness.

[0384] After the lining tube 1 has been fully expanded, the reactive resin in the layer of fiber material 20 is cured in a known manner by introducing a UV radiation source 430 into the interior of the calibration bag 410. Instead of a UV-curing reactive resin containing appropriate photoinitiators that trigger the polymeric cross-linking reaction of the resin, a thermally curable reactive resin can alternatively be used. In this case, curing is carried out by introducing heated air, heated water, or hot steam into the calibration bag 410.

[0385] Fig. 2 shows a winding device 300 for manufacturing the lining tube 1 according to the invention. In this device, the inner film tube 10 with the structure shown in Fig. 1 is first stripped onto the outside of a winding tube 320 of the winding device 300. During subsequent manufacturing, the inner film tube 10 is continuously unwound from the winding mandrel 330 by means of circulating transport belts 332 arranged in the area of ​​the winding mandrel 330. The fiber tape(s) 22 are unwound from a supply roll in a known manner, as shown in Fig. 2, and wound helically around the outside of the inner film tube 10, so that a closed layer of fiber material 20 is formed. An outer film tube 40, which is opaque to styrene and preferably also to UV light and shorter-wavelength visible light, and optionally another outer film tube 50 made of tear-resistant material, are then applied to this as further closed layers, as shown in Fig. 2.2. However, for the sake of clarity, only some reference symbols are shown, or not shown at all.

[0386] 1 lining hose

[0387] 6 Pressurized gas source

[0388] 10 inner foil tubes or inner foil tubes

[0389] 10.1 First layer of the inner film tube with at least 30 wt.% m-LLDPE (at least one such layer in the inner film tube according to the invention) 10.2 Bonding layer preferably consisting of adhesion promoter (at least one such layer in the inner film tube according to the invention)

[0390] 10.3 At least one PA layer containing a polyblock amide that includes both soft elastic segments and stiff, inflexible, hard polyamide blocks.

[0391] 20 layers of fiber material

[0392] 22 Fiber tape

[0393] 30 Longitudinal pull tape

[0394] 40 Outer film tube (tube outer film)

[0395] 40.1 further first layer with at least 30 wt.% m-LLDPE (at least one such layer in the outer film of the hose according to the invention)

[0396] 40.2 at least one additional bond-broker layer

[0397] 40.3 At least one PA layer containing a polyblock amide that includes both soft elastic segments and stiff, inflexible, hard polyamide blocks.

[0398] 40.4 second outer bonding layer preferably made of bonding agent

[0399] 40.5 further layer with at least 30 wt.% m-LLDPE (at least one such layer in the outer film of the hose according to the invention)

[0400] 40.6 Layer of nonwoven material, in particular PE, PP or polyester nonwoven or alternatively glass nonwoven, which faces the tubular layer of fiber material and preferably lies against it

[0401] 50 additional outer foil tubes made of reinforced tensile-resistant material, such as a truck tarpaulin

[0402] 52 Controlled crack point

[0403] 100 sewer pipes

[0404] 110 first pipe section

[0405] 120 second pipe section

[0406] 200 Packers 202 Packer lids

[0407] 210 tension strap

[0408] 300 winding device

[0409] 310 Supply roll for longitudinal pull belt 320 Winding tube

[0410] 330 winding mandrel

[0411] 332 transport belts

[0412] 400 channel shaft

[0413] 405 Cross seam

[0414] 406 channels

[0415] 410 Calibration bag

[0416] 420 knots

[0417] 430 UV radiation source

Claims

52 Patent claims 1. Lining hose for the rehabilitation of a defective sewer pipe or manhole, comprising an inner foil hose, a tubular layer of a carrier material impregnated with a curable reactive resin arranged around it, wherein the inner foil hose has a multilayer film comprising at least one layer of one or more homo- or copolymers of polyolefins and at least one barrier layer of one or more homo- or co-polyamides arranged on it, characterized by that the barrier layer consists of one or more homo- or co-polyamides and contains at least one polyblock amide, and / or that the layer of one or more homo- or copolymers of polyolefins contains wholly or partially at least one metallocene linear low-density polyethylene (m-LLDPE), wherein the barrier layer, consisting of one or more homo- or copolymers, is arranged directly adjacent to the layer of a support material.

2. Lining hose for the rehabilitation of a defective sewer pipe or manhole according to claim 1, characterized by that the at least one layer of one or more homo- or copolymers of polyolefins and at least one barrier layer of one or more homo- or co-polyamides arranged on it are connected to each other via at least one bonding layer, in particular at least one layer of an adhesion promoter.

3. Lining hose for the rehabilitation of a defective sewer pipe or manhole according to one of the preceding claims, characterized by, 53 that the layer consists of one or more homo- or copolymers of polyolefins containing at least 30 wt. % metallocene linear low-density polyethylene (m-LLDPE).

4. Lining hose for the rehabilitation of a defective sewer pipe or manhole according to one of the preceding claims, characterized by that the polyblock amide is an elastomeric polyblock amide, in particular polyetherblock amide (PEBA).

5. Lining hose for the rehabilitation of a defective sewer pipe or manhole according to one of the preceding claims, characterized by that the polyblock amide is contained in the barrier layer at a wt% to 0.1 to 60.0%.

6. Lining hose for the rehabilitation of a defective sewer pipe or manhole according to one of the preceding claims, characterized by that one or more homo- or co-polyamides are selected from the group of thermoplastic aliphatic, semi-aromatic or aromatic homo- or co-polyamides, such as aliphatic diamines with 2-10 carbon atoms, in particular hexamethylenediamine, aromatic diamines with 6-10 carbon atoms, in particular p-phenylenediamine and / or from aliphatic dicarboxylic acids, aromatic dicarboxylic acids with 6-14 carbon atoms, such as adipic acid, terephthalic acid or isoterephthalic acid and / or from lactams with 4-10 carbon atoms, in particular from s-caprolactam, polyamides such as PA 6, PA 11, PA 12, PA 66, PA 6.10, PA 6.12, PA 666, PA 61, PA 6T or corresponding copolymers or mixtures of at least two of the aforementioned polyamides are used.

7. Lining hose for the rehabilitation of a defective sewer pipe or manhole according to one of the preceding claims, characterized by that one or more homo- or copolymers of polyolefins are selected from 54 the group of thermoplastic olefin homo- or copolymers, such as α,β-unsaturated olefins with 2-10 carbon atoms, ethylene homopolymers (polyethylenes, PE), LDPE (high-density polyethylene in the range of 0.86-0.93 g / cm³). 3 ), LLDPE (Linear Low Density Polyethylene), HDPE (High Density Polyethylene in the range of 0.94 and 0.97 g / cm³) 3 ), propylene homopolymers (polypropylene, PP), butylene homopolymers (polybutylene, PB), isobutylene homopolymers (polyisobutylene, PI) or mixtures of at least two of the aforementioned polymers.

8. Lining hose according to one of the preceding claims, characterized by that the tubular layer impregnated with the curable reaction resin is selected from the group of fiberglass, nonwoven, fleece or fiber tape, or at least a helically overlapping wound fiber band or at least a fiber band extending in the longitudinal direction of the lining tube, overlapping at its longitudinal edges, which is guided around the at least one barrier layer and is arranged with its inner side directly against the barrier layer.

9. Lining hose according to one of the preceding claims, characterized by that the inner foil tube is permeable to UV light and that the reaction resin is a resin that can be cured by irradiation with UV light, or that the reaction resin is a resin that can be cured by heat, and the inner foil tube is designed to be exposed to heated water, hot steam or heated air to cure the resin.

10. Lining hose according to one of the preceding claims, characterized by that a longitudinal tensile band extending in the longitudinal direction of the lining tube is arranged on the layer of carrier material, which contains glass fibers and / or glass fiber rovings running in the longitudinal direction of the lining tube, which are designed to resist axial forces during the insertion of the 55 To insert and transfer the lining hose into a sewer pipe or manhole.

11. Method for lining a defective sewer pipe, characterized by the following procedural steps: Inserting a lining hose according to one of the preceding claims into a defective sewer pipe, sealing the two ends of the lining hose with a packer, expanding the lining hose by introducing a pressure medium, in particular compressed air, into the inner foil hose such that the lining hose expands radially and its outer surface rests against the inner wall of the sewer pipe, and curing the reaction resin in the layer of carrier material, in particular by introducing a radiation source into the interior of the inner foil hose.

12. Method for lining a defective manhole (400), characterized by the following process steps: Sealing a first end of the lining hose (1) to be inserted into the manhole (400), in particular by sewing or clamping or gluing along a transverse seam (405), Attaching the second end of the lining hose to a packer (200), inserting the first sealed end of the lining hose (1) into the manhole to be rehabilitated (400), Inserting a calibration bag (410) closed at one end, in particular by a knot (420), into the inner foil tube (10), expanding the calibration bag (410) by introducing a pressure medium, in particular compressed air, into the interior of the calibration bag (410) such that the lining tube (1) expands radially and its outer side rests against the inner wall of the channel shaft (400), and curing the reaction resin in the layer of fiber material (20), in particular by introducing a radiation source (430) into the interior of the calibration bag (410).

13. Use of a multilayer film comprising at least one layer of one or more homo- or copolymers of polyolefins and at least one barrier layer of one or more homo- or co-polyamides arranged on top of this layer, wherein the barrier layer consists of one or more homo- or co-polyamides and contains at least one polyblock amide, and / or the layer consisting of one or more homo- or copolymers of polyolefins contains wholly or partially at least one metallocene linear low-density polyethylene (m-LLDPE), wherein the barrier layer is made of one or more homo- or copolymers for direct arrangement on the layer made of a carrier material, as an inner film tube in a lining tube according to one of claims 1 to 10.

14. Use of a lining hose according to one of claims 1 to 10 for the rehabilitation of a defective sewer pipe or sewer shaft.

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