Method for manufacturing tape

Abstract

The tape (1) obtained by the following method of manufacturing tape requires less adhesive than conventional tape with the same adhesive properties, the method comprising the steps of: a) mixing ASE thickener with water to produce (ASE) thickener-water mixture (7); b) producing adhesive dispersion (8) from adhesive and solvent; c) providing fabric carrier (2); d) applying (ASE) thickener-water mixture (7) to fabric carrier; e) applying adhesive dispersion (8) to (ASE) thickener-water mixture (7) to obtain tape; f) drying the obtained tape, wherein the thickener, particularly ASE thickener, is saturated with water, and the adhesive dispersion (8) is applied after or simultaneously with the application of (ASE) thickener-water mixture (7).

Description

[0001] This invention relates to a method for manufacturing adhesive tape, comprising the following steps:

[0002] a) Mix the thickener, more specifically the ASE thickener, with water to produce an (ASE) thickener-water mixture;

[0003] b) The adhesive dispersion is produced from the adhesive and solvent;

[0004] c) Provide a fabric carrier;

[0005] d) Apply the (ASE) thickener-water mixture to the fabric carrier;

[0006] e) Apply the adhesive dispersion to an (ASE) thickener-water mixture to obtain an adhesive tape;

[0007] f) The dried tape.

[0008] Adhesive tape has long been used in industry to manufacture cable bundles. In this application, tape is used to bundle multiple electrical wires before installation or in an already assembled state, in order to reduce the space occupied by the wire bundle and provide additional protection.

[0009] A fabric carrier with a pressure-sensitive adhesive applied to one side is known from DE 10 2011 075 160 A1. The pressure-sensitive adhesive is composed of a dried electron beam crosslinked polymeric acrylate dispersion. The acrylate dispersion comprises acrylate monomers and olefinically unsaturated comonomers that are not acrylates. The pressure-sensitive adhesive further contains 10 to 100% by weight of a tackifier. Here, the aqueous acrylate dispersion is first applied to the carrier and then dried.

[0010] Furthermore, EP 2 695 926 A1 provides a tape for protecting (wrapping) cables, which has a carrier and a dried polymer dispersion applied to one side of the carrier, wherein the polymer consists of 95 to 100 wt% ethyl acrylate and / or 2-ethylhexyl acrylate and 0.0 to 5.0 wt% olefinic unsaturated monomers having acid or anhydride functionality.

[0011] The problem with applying polymer dispersions to fabric carriers is that low-viscosity polymer dispersions penetrate the carrier because the carrier is very coarse, porous, and / or permeable. This creates two problems: first, a very large amount of polymer dispersion must be used to achieve full-area application on one side of the fabric; and second, when the dried tape is wound into rolls, the individual layers adhere to each other and can no longer be unwound.

[0012] On the other hand, while it is indeed impossible to penetrate between the application and drying points when using high-viscosity polymer dispersions, these dispersions are difficult to process. They must be applied to the carrier under high pressure via pipeline and die (nozzle) systems; the dies used are often not designed for such high operating pressures. Against this backdrop, there is a fundamental interest in using low-viscosity adhesives because they are easier to handle.

[0013] Therefore, WO 2019 / 086705 recommends providing a strip carrier on which a thickener is applied and a water-based dispersion adhesive (dispersion-based adhesive), more particularly an acrylate-based or polyurethane-based water-based dispersion adhesive, is applied separately. The water-based dispersion adhesive and the thickener come into contact with each other after application or during application. The dispersion adhesive is then dried to obtain the tape.

[0014] The disadvantage of the tapes disclosed there is that the viscosity range of the thickener is inherently very small. However, the application process and the properties of the finished tape can be controlled by viscosity. If the possibility of viscosity variation is limited, then the possibility of variation in the properties of the finished tape is also limited.

[0015] Therefore, the object of the present invention is to improve the method for manufacturing adhesive tape, and in particular to expand the range (breadth, bandbreite) for controlling the properties of adhesive tape.

[0016] According to the invention, the objective is achieved by saturating the thickener, more particularly the ASE thickener, with water in a method of the type described above, and applying the adhesive dispersion after or simultaneously with the application of the thickener-water mixture, more particularly the (ASE) thickener-water mixture. The viscosity of the thickener layer varies depending on the ratio of the thickener, more particularly the ASE thickener, to water. Therefore, the properties of the thickener layer can be altered, and thus the properties of the tape can be altered, which can thereby be adjusted over a wide range. These controllable properties include the penetration depth of the adhesive dispersion, which in turn affects the cohesive strength.

[0017] In addition to ASE thickener, a preferred embodiment of the present invention also uses HASE (hydrophobic modified alkali-swellable emulsion) thickener.

[0018] When the following refers to a (ASE) thickener-water mixture, those skilled in the art will understand that this disclosure is not limited to preferred mixtures of ASE thickener and water, but rather that any mixture of thickener and water is generally understood by those skilled in the art.

[0019] In the context of this invention, "water-saturated" means that water is present in excess in the (ASE) thickener-water mixture, so that all the thickener has been consumed, and the (ASE) thickener-water mixture cannot combine with any more water. Therefore, unlike the prior art, the method of this invention does not use pure thickener (100%), but rather a thickener-water mixture.

[0020] Using the method according to the invention, an open (pore-shaped), coarse-pore, porous, and / or permeable carrier can first be coated with an adhesive dispersion without material penetration. Such material penetration would cause the adhesive to penetrate deeply into or through the carrier and would not be effective as a coating. This, in turn, would have the undesirable effect of requiring an unnecessarily large amount of adhesive to achieve a specific peel adhesion. Using the invention, the adhesive can penetrate only into the upper layer of the carrier, but not into the deeper carrier layers, let alone the entire carrier.

[0021] The thickener layer acts as a buffer between the fabric carrier and the adhesive. This buffer layer allows for very effective control over the properties of the tape. Depending on the thickness of the buffer layer, good or weak anchoring of the adhesive can be achieved. If the buffer layer is thick, the adhesive dispersion sinks only slowly, resulting in only weak adhesive anchoring within the carrier. Conversely, with only a thin buffer layer, the adhesive penetrates far into the carrier, leading to stronger adhesive anchoring. Because the buffer layer is in the form of a thickener, more specifically an ASE thickener, the amount of adhesive dispersion that must be applied to the carrier is reduced. Since adhesive dispersions are more expensive than thickeners, this method can reduce the cost of the tape.

[0022] Further cost reductions compared to conventional methods are due to the absence of high-viscosity substances requiring processing. Furthermore, if the adhesive used is not high-viscosity, the cost and complexity of preparation and subsequent cleaning are significantly lower.

[0023] A further effect of the thickener layer is to smooth the highly irregular surface of the fabric carrier. In this way, the coating appearance is improved when the adhesive dispersion is applied, which is reflected in improved peel adhesion.

[0024] Drying following the application of the (ASE) thickener-water mixture and adhesive dispersion results in the evaporation of water and any other solvents, and produces a continuous polymer film present on and within the fabric carrier.

[0025] As a result of the thickener layer, the adhesive is concentrated near the surface (enriched at the surface). The adhesive has a relatively narrow distribution. Due to the positioning of the adhesive in the upper layer, the fibers of the lower layer of the fabric carrier are less likely to stick together, resulting in less compression / compactness of the rolls after subsequent cutting and winding operations due to winding tension.

[0026] If the weight ratio of water to thickener, more particularly ASE thickener, is 1:1 to 10:1, more preferably 1:1 to 5:1, and even more particularly 1:1 to 2:1, a particularly suitable viscosity of the (ASE) thickener-water mixture is achieved. This weight ratio, or the viscosity it produces, results in a tape in which there is a good trade-off between the desired anchoring and the amount of adhesive dispersion required.

[0027] If the (ASE) thickener-water mixture contains 5 to 25% by weight, preferably 10 to 20% by weight, of an adhesive, and more precisely, particularly preferably the same adhesive also contained in the adhesive dispersion, then particularly good anchoring in the fabric carrier is achieved using the method according to the invention. In this way, even better bonding is achieved between the thickener layer and the adhesive layer, which in turn improves the anchoring of the adhesive layer in the fabric carrier.

[0028] Preferably, the adhesive dispersion has a solid content of 10 to 70% by weight, more particularly 50 to 60% by weight of adhesive, and the thickener layer has a solid content of 10 to 20% by weight of adhesive. In this way, particularly good anchoring of the adhesive in the fabric carrier is achieved. Furthermore, the amount of adhesive used is reduced without any degradation in adhesive performance.

[0029] In a further particularly preferred variant of the method of the invention, up to 20% by weight, preferably up to 10% by weight, and more particularly up to 5% by weight, of thickener is used in the adhesive dispersion. This adjusts the viscosity of the adhesive dispersion so that it can be applied particularly effectively to the thickener layer, precisely both with and without the application of the thickener-water mixture and the adhesive dispersion in a slightly delayed manner (ASE) and simultaneously. Compared to prior art methods, the method of the present invention requires significantly less thickening of the adhesive dispersion, resulting in an adhesive dispersion that remains easy to handle, easy to pump, and easy to apply.

[0030] In a particularly preferred embodiment of the method, the adhesive layer (=upper layer=functional layer) has a lower viscosity than the thickener layer (=lower layer=buffer layer or filler layer). Conversely, preferably, the upper layer has a higher adhesive content than the lower layer.

[0031] (ASE) Thickener-water mixtures can be applied immediately before aqueous dispersion adhesives. In their respective cases, when wet-to-wet coating is performed in a single operation, the time difference is preferably 0.1 ms (especially when using a dual-die head) to 100 s (when using a second separate coating system), more preferably 0.5 ms to 20 s, especially preferably 1 ms to 10 s, and even more particularly 1 ms to 10 ms.

[0032] In another preferred variant, a (ASE) thickener-water mixture and an aqueous dispersion adhesive are applied simultaneously.

[0033] The concept used in this invention is to produce a rollable tape by not directly applying and drying a high-viscosity dispersion adhesive to one side of a carrier layer. Because high-viscosity dispersion adhesives are difficult to process, they must be pressed (extruded) through a slotted die under high pressure and are first pushed to the die via a pipeline system. The processing of high-viscosity dispersion adhesives is related to the generation of high pressure.

[0034] The concept used in this invention is to apply a thickener and adhesive dispersion onto a fabric carrier. The thickener layer acts as a buffer for the adhesive dispersion, allowing the adhesive dispersion to penetrate very little into the fabric carrier and, more importantly, preventing it from penetrating the carrier.

[0035] Because, in the case of this invention, the (ASE) thickener-water mixture and the adhesive dispersion are applied to the same side of the fabric carrier without any substance penetrating, the side of the fabric carrier away from the application side remains completely dry; in other words, it is not contaminated by either the (ASE) thickener-water mixture or the adhesive dispersion. After the (ASE) thickener-water mixture and the adhesive dispersion have dried, the tape can be wound without any problems.

[0036] According to a preferred embodiment of the invention, the (ASE) thickener-water mixture is applied to the entire area of ​​the fabric carrier. More preferably, the adhesive dispersion is also applied to the entire area of ​​the (ASE) thickener-water mixture that has already been applied to the entire area.

[0037] The method of the present invention can have many variations.

[0038] For example, (ASE) thickener-water mixtures can be applied to the entire area of ​​a fabric carrier, while adhesive dispersions are partially coated, more particularly in the form of one or more strips extending in the machine direction.

[0039] Furthermore, the (ASE) thickener-water mixture may be applied in part, and then the adhesive dispersion may be applied only to the areas in which the (ASE) thickener-water mixture has been applied. More preferably, the (ASE) thickener-water mixture and the adhesive dispersion are applied in the form of one or more strips extending in the machine direction, wherein the strips of the (ASE) thickener-water mixture preferably have a wider width than the strips of the adhesive dispersion.

[0040] (ASE) Thickener-water mixtures and adhesive dispersions are preferably applied using a double-slot die, which preferably has a slot width (also called height) of 20 to 700 μm, more particularly 50 to 500 μm, and even more particularly 100 to 300 μm, and a length corresponding to the width of the fabric carrier; here, a length of 10 to 4000 mm, preferably 1000 to 2000 mm, is used, however, all other die lengths are also conceivable.

[0041] (ASE) Thickener-water mixtures and adhesive dispersions can also be applied via two slot dies arranged in series.

[0042] Advantageously, the fabric carrier is guided around the coating roller (calendering roller, Gieβwalze) and rests on the coating roller on the side away from the application side, and is pushed forward (feeded) by the rotational movement of the coating roller. Preferably, a double-slot die is provided on the adhesive side of the fabric carrier, where the feed rate of the fabric carrier and the slot spacing of the double-slot die are selected such that after the (ASE) thickener-water mixture is applied to the fabric carrier, the adhesive dispersion is applied to the (ASE) thickener-water mixture for only, for example, 1 to 10 ms. The (ASE) thickener-water mixture prevents the adhesive dispersion from penetrating deeply into the fabric carrier. A low level of penetration of the adhesive dispersion into the fabric carrier is desired, thereby allowing the fabric carrier and the dispersed adhesive to form a strong bond with each other. After application, the adhesive and thickener are dried to obtain a rollable pressure-sensitive adhesive tape.

[0043] It is advantageous to use a dispersion adhesive having a viscosity of 0.2 Pa*s to 30 Pa*s ± 5 Pa*s, more particularly 0.5 Pa*s to 15 Pa*s ± 5 Pa*s. More preferably, the viscosity of the dispersion adhesive is 2 to 5 Pa*s. It is particularly advantageous if the viscosity of the (ASE) thickener-water mixture is similar to or more preferably greater than the viscosity of the adhesive dispersion.

[0044] Using an ARES rheometer (Rheometric Scientific) at room temperature and 100 s -1 Viscosity was measured using a cone / plate system with a diameter of 50 mm at a shear rate.

[0045] An apparatus for carrying out the method of the present invention includes a coating roll (calendering roll, Giebwelle) having a longitudinal coating roll direction and a double slot die having a longitudinal slot direction, the double slot die being arranged along the longitudinal coating roll direction, preferably, the two longitudinal directions being arranged parallel to each other.

[0046] The first and second slotted die heads are arranged on one side of the fabric carrier.

[0047] A free gap is provided between the double-slot die and the coating roller, forming a slot through which the fabric carrier can be fed. The fabric carrier deflects around the coating roller and advances through the coating roller or another device. The feed direction of the fabric carrier is laterally, preferably perpendicular to the longitudinal direction of the coating roller and / or the double-slot die.

[0048] The first slot die of the dual slot die is provided with a supply device for a (ASE) thickener-water mixture, wherein the slot die is in fluid conductive communication with the supply device for the (ASE) thickener-water mixture. The (ASE) thickener-water mixture is preferably disposed in a storage container and delivered to the first slot die via a piping system as part of the supply device, and from there applied to the side of the fabric carrier away from the coating roller.

[0049] The second slot die of the dual-slot die is connected to a second supply device having an aqueous adhesive dispersion. The second slot die is also part of the dual-slot die and is fluidly connected to a reservoir for the adhesive dispersion via the second supply device. According to the invention, the first slot die is arranged ahead of the second slot die in the feed direction. This ensures that the first slot die first applies the thickener to the side of the fabric carrier away from the coating roller, and then the second slot die immediately applies the adhesive dispersion to the fabric carrier already coated with the thickener.

[0050] Preferably, a drying device for the tape is provided downstream of the double-slot die in the feed direction.

[0051] The drying device removes water from the aqueous dispersion adhesive, thereby drying the dispersion adhesive on the fabric carrier.

[0052] The selection of adhesive dispersions and thickeners is described below.

[0053] Therefore, the method of the present invention is particularly useful for manufacturing tapes, especially tapes for wrapping (wrapping) cables, the tape comprising, or consisting of, a pressure-sensitive adhesive in the form of a preferably woven carrier and a dried polymer dispersion applied to at least one side of the carrier, the polymer being composed of:

[0054] (a) 95.0 to 100.0% by weight of n-butyl acrylate and / or 2-ethylhexyl acrylate

[0055] (b) 0.0% to 5.0% by weight of olefinic unsaturated monomers having acid or anhydride functionality.

[0056] The polymer is preferably composed of 95.0 to 99.5% by weight of n-butyl acrylate and / or 2-ethylhexyl acrylate and 0.5 to 5% by weight of an olefinic unsaturated monomer having acid or anhydride functionality, and more preferably composed of 98.0 to 99.0% by weight of n-butyl acrylate and / or 2-ethylhexyl acrylate and 1.0 to 2.0% by weight of an olefinic unsaturated monomer having acid or anhydride functionality.

[0057] In addition to the acrylate polymers listed, the pressure-sensitive adhesive may also be mixed in the same amounts as the tackifiers and / or additives mentioned below, such as light stabilizers or aging inhibitors, in addition to any residual monomers present (if any).

[0058] In particular, no other polymers such as elastomers are present in the pressure-sensitive adhesive, which means that the polymer of the pressure-sensitive adhesive consists only of monomers (a) and (b) in the proportions shown.

[0059] Preferably, n-butyl acrylate forms monomer (a).

[0060] As monomers (b), acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid and / or maleic anhydride are advantageously considered.

[0061] Preferred formula I (meth)acrylic acid,

[0062]

[0063] Where R 3 =H or CH3; preferably, optionally, a mixture of acrylic acid or methacrylic acid is used. Acrylic acid is particularly preferred.

[0064] According to a particularly preferred variant, the polymer composition is as follows:

[0065] (a) 95.0 to 100.0% by weight, preferably 95.0 to 99.5% by weight, more preferably 98.0 to 99.0% by weight of n-butyl acrylate, and

[0066] (b) 0.0 to 5.0% by weight, preferably 0.5 to 5.0% by weight, more preferably 1.0 to 2.0% by weight of acrylic acid.

[0067] Polymer dispersions are prepared by emulsion polymerization of the components mentioned. A description of this process can be found, for example, in: Peter A. Lovell and Mohamed S. El-Aasser, “Emulsion Polymerization and Emulsion Polymers” – Wiley-VCH 1997 – ISBN 0-471-96746-7 or EP 1 378 527 B1.

[0068] In polymerization, it cannot be ruled out that not all monomers will be converted into polymers. In this case, it is obvious that the residual monomer content should be as low as possible.

[0069] The preferred adhesives are those polymer dispersions that include a residual monomer content of less than or equal to 1% by weight, more particularly less than or equal to 0.5% by weight (based on the mass of the dried polymer dispersion).

[0070] The adhesive dispersion is a pressure-sensitive adhesive, meaning it allows for durable adhesion to virtually any substrate even under relatively weak applied pressure, and can be re-separated from the substrate with virtually no residue after use. At room temperature, the pressure-sensitive adhesive is permanently pressure-sensitive, thus possessing sufficiently low viscosity and high contact tack to wet the surface of the corresponding substrate even under low applied pressure. The adhesiveness of the dispersion adhesive depends on its adhesive properties, and its re-separability depends on its cohesive properties.

[0071] To achieve the properties of pressure-sensitive adhesives, the dispersion adhesive must exhibit viscoelastic properties above its glass transition temperature at the processing temperature. Since cable bundle winding (wrapping) is carried out at standard ambient temperatures (approximately 15°C to 25°C), the glass transition temperature of the pressure-sensitive adhesive formulation is preferably below +15°C (determined according to DIN 53 765 by DSC (differential scanning calorimetry) at a heating rate of 10 K / min).

[0072] The glass transition temperature of acrylate copolymers can be estimated from the glass transition temperature of homopolymers and their relative proportions using the Fox equation.

[0073] To obtain polymers with a desired glass transition temperature, such as pressure-sensitive adhesives or heat-sealing substances, it is advantageous to select a quantitative composition of the monomer mixture to give the desired T value of the polymer according to an equation (G1) similar to the Fox equation. G Value (see TGFox, Bull. Am. Phys. Soc. 1956, 1, 123).

[0074]

[0075] Depending on the amount added, compatibility, and softening temperature, the tackifier that may be added will inevitably increase the glass transition temperature by approximately 5 to 40 K.

[0076] Therefore, acrylate copolymers having a glass transition temperature of at most 0°C are preferred.

[0077] According to ASTM D3330, the polymer of the present invention has a peel adhesion to steel of at least 1.0 N / cm (30 g / m² on a 23 μm polyester film carrier). 2 (Base weight of the dispersion adhesive).

[0078] According to the general understanding of technicians, "tackifier resin" refers to oligomeric or polymeric resins that improve the self-adhesiveness (adhesiveness, inherent adhesion) of pressure-sensitive adhesives compared to those without tackifier resin but otherwise identical.

[0079] The use of tackifiers to improve the peel adhesion of pressure-sensitive adhesives is generally known. This effect is also achieved by adding up to 15% by weight (corresponding to <15 parts by weight), or 5 to 15% by weight (based on the mass of the dry polymer dispersion), to the dispersion adhesive. Preferably, 5 to 12%, more preferably 6 to 10% by weight (based on the mass of the dry polymer dispersion), is added.

[0080] Suitable tackifiers, also known as tackifying resins, generally include compounds of all known classes. Tackifiers are, for example, hydrocarbon resins (e.g., polymers based on unsaturated C5 or C9 monomers), terpene phenolic resins, polyterpene resins based on raw materials such as α-pinene or β-pinene, aromatic resins such as coumarone-indene resins, or resins based on styrene or α-methylstyrene such as rosin and its derivatives, such as disproportionated, dimerized, or esterified rosin, such as reaction products with ethylene glycol, glycerol, or pentaerythritol, to name just a few. Preferred resins are those without readily oxidizable double bonds, such as terpene phenolic resins, aromatic resins, and particularly preferred are resins prepared by hydrogenation, such as hydrogenated aromatic resins, hydrogenated polycyclopentadiene resins, hydrogenated rosin derivatives, or hydrogenated polyterpene resins.

[0081] Preferred resins are those based on terpene phenolic resins and rosin esters. Also preferred are tackifying resins having a softening point greater than 80°C according to ASTM E28-99 (2009). Particularly preferred are resins based on terpene phenolic resins and rosin esters having a softening point greater than 90°C according to ASTM E28-99 (2009). The resins are effectively used in dispersion form. In this way, they can be easily mixed with polymer dispersions in a finely dispersed form.

[0082] A particularly preferred variant of the invention is one in which no tackifying resin is added to the pressure-sensitive adhesive at all.

[0083] Surprisingly and unexpectedly for technicians, the absence of tackifier resin in the tape—as would have been expected—resulted in insufficient peel adhesion. Furthermore, surprisingly, the edge-lifting behavior was also quite poor.

[0084] The adhesive dispersion is diluted with a solvent suitable for use in adhesive dispersions. Water is a particularly preferred solvent. The viscosity of the unthickened adhesive dispersion is preferably in the range of η = 0.1 to 10 Pa*s.

[0085] Furthermore, the method of the present invention can also be used to apply adhesives based on polyurethane dispersions.

[0086] Another typical dispersion adhesive is described in section 3.5 of the professional book G. Habenicht's "Kleben–Grundlagen, Technologien, Anwendungen" [Adhesive bonding – Principles, technologies, applications], 2009, Springer Verlag, Berlin / Heidelberg.

[0087] After mixing the thickener and dispersion binder, the fraction of the thickener or rheology modifier is in the range of 0.1 to 5% by weight, based on the mass of the dried polymer dispersion.

[0088] There are fundamental differences between organic and inorganic rheology additives.

[0089] Organic thickeners are further divided into two basic modes of action: (i) thickening of the aqueous phase, i.e., non-associative, and (ii) association between thickener molecules and particles, in the presence of a stabilizer (emulsifier). The first group (i) of compounds is represented by water-soluble polyacrylic acid and polycoacrylic acid. These form polyelectrolytes with high hydrodynamic volumes in alkaline media. Technicians also refer to these simply as ASE (alkali-swellable emulsions). They are characterized by high static shear viscosity and strong shear thinning. Another class of compounds consists of modified polysaccharides, especially cellulose ethers such as carboxymethyl cellulose, 2-hydroxyethyl cellulose, carboxymethyl-2-hydroxyethyl cellulose, methyl cellulose, 2-hydroxyethylmethyl cellulose, 2-hydroxyethylethyl cellulose, 2-hydroxypropyl cellulose, 2-hydroxypropylmethyl cellulose, and 2-hydroxybutylmethyl cellulose. Also included in this class are less commonly used polysaccharides such as starch derivatives and specific polyethers.

[0090] In principle, (ii) the active group (group) of an associative thickener is a block copolymer having a water-soluble mesoblock and a hydrophobic end block, wherein the end blocks interact with the particles or with themselves and thus form a spatial (three-dimensional) network containing the particles. Those skilled in the art are familiar with the following as typical representatives: HASE (hydrophobically modified alkali-swellable emulsion), HEUR (hydrophobically modified ethylene oxide urethane), or HMHEC (hydrophobically modified hydroxyethyl cellulose). In the case of HASE thickeners, the mesoblock is ASE, and the end blocks are typically long hydrophobic alkyl chains connected via polyoxyethylene bridges. In the case of HEUR, the water-soluble mesoblock is polyurethane, and in the case of HMHEC, it is 2-hydroxyethyl cellulose. In particular, nonionic HEUR and HMHEC are substantially insensitive to pH.

[0091] These types of base-activated thickeners are commercially available and are described, for example, in an article titled "Developments in rheology modifiers suitable for use in surfactant containing formulations" (October 2002) by Charles Jones, Sylvie Doulut, and Paul Reeve (Rohm & Haas Company).

[0092] Depending on their structure, associative thickeners result in more or less Newtonian (independent of shear rate) or pseudoplastic (shear-liquefaction) flow behavior. Occasionally, they also exhibit thixotropic properties, meaning that they are time-dependent in addition to the shear force dependence of viscosity.

[0093] Inorganic thickeners are typically layered silicates of natural or synthetic origin, examples being lithium montmorillonite and montmorillonite. Upon contact with water, the individual layers separate from each other. Due to the different charges on the faces and edges of the flakes, they form a space-filled house of cards structure when at rest, resulting in high static shear viscosity up to the yield point. Upon shearing, the house of cards structure collapses and a significant decrease in shear viscosity is observed. Depending on the charge, concentration, and geometry of the flakes, the formation of the structure can take some time, thus thixotropy can also be achieved using this inorganic thickener.

[0094] Layered silicates, foliated silicates, or leaf silicates are known to be used as ion exchangers. Known layered silicates are clay minerals such as montmorillonite, chlorodiazepite, lithium montmorillonite, saponite, zinc montmorillonite, bedesulfurite, sodalite, illite, halloysite, palygorskite, and / or sepiolite, as well as distearatedimonium hectoritite. Lithium montmorillonite is M... 0,3 +(Mg 2,7 Li 0,3 [Si4O] 10 [(OH)2], M + Usually=Na + It is a monoclinic clay mineral belonging to the chlorite family and similar to montmorillonite. According to the invention, modified triplyl-layered silicates or modified triplyl clay minerals used synonymously herein, such as illite, chlorite, or vermiculite, are preferred. Particularly preferred for use in the pressure-sensitive adhesives of the invention are modified triplyl silicates such as montmorillonite, lithium montmorillonite, or chlorite.

[0095] According to the manufacturers, unmodified layered silicates can be activated with polar additives and high shear forces to develop their full activity (e.g., regarding those from Rockwood Additives Ltd.). VP-V (Quaternium-90 Bentonite) or from Rheox Inc. Product information for 38 (organic derivatives of magnesium-layered silicate (lithium montmorillonite)).

[0096] This activation of layered silicates, i.e., their conversion to a swollen form, is achieved by treating the layered silicates with a polar liquid and high shear force. The resulting layered silicates are considered modified layered silicates. Similarly, the name from Rockwood Corporation can also be used... Laptonite SL Laptonite Laptonite Laptonite Optigel Modified layered silicates. Preferred are natural and synthetic organic surface-modified trilayer-layered silicates.

[0097] Laptonite is a colloidal synthetic layered silicate (lithium montmorillonite, containing lithium) with lamellar diameters of 20 to 30 nm, preferably about 25 nm, and a thickness of about 1 nm. Due to the small size of the lamellars, it is possible to reconstruct the house of cards structure very rapidly, wherein the edges of the lamellars, in their respective cases, rest against the surfaces of adjacent layered silicate lamellars. Trilayer silicates can be readily stirred into water and form clear, colorless dispersions. They can form gels (high-viscosity colloidal dispersions) or sols (low-viscosity colloidal dispersions).

[0098] For the thickener layer of this invention, a non-associated thickener, namely an ASE thickener, is preferably used. The viscosity of the ASE thickener is approximately 10s. -1The preferred shear rate is η = 15 to 100 Pa*s.

[0099] In cases where the adhesive dispersion also contains a thickener, the latter can be a non-associative or associative thickener.

[0100] Thickeners can be partially stirred directly into the adhesive dispersion, or advantageously, partially pre-dispersed or pre-diluted in water.

[0101] Thickener suppliers include, for example, OMG Borchers, Omya, Byk Chemie, Dow Chemical Company, Evonik, Rockwood, or Münzing Chemie.

[0102] Suitable carriers include all carrier materials in principle, with fabric carriers being preferred, and woven fabrics being even more preferred, especially polyester fabrics.

[0103] As a carrier material for tape, all known woven carriers can be used, such as knitted fabrics (loop knitted fabrics), loose fabrics, tapes, braided fabrics, needle-punched pile textiles, felts, woven fabrics (including plain weave, twill weave and satin weave), knitted fabrics (including warp knitted fabrics and other knitted fabrics) or nonwoven fabrics (nonwoven webs). The term "nonwoven fabric (nonwoven webs)" is understood to mean at least sheet-like structures of textiles according to EN 29092 (1988), as well as stitch-woven nonwovens and similar systems.

[0104] Laminated woven and knitted spacer fabrics can also be used.

[0105] These types of spacer fabrics are disclosed in EP 0 071 212 B1. The spacer fabric is a cushion-like layered structure having a cover layer composed of a nonwoven fabric of fibers or filaments, a back layer, and individual fixing fibers or bundles of such fibers present between these layers. These fibers are distributed over regions of the layered structure, needle-punched through the granular layers, and connect the cover layer and the back layer to each other. As an additional, but non-mandatory, feature, the fixing fibers according to EP 0 071 212 B1 contain particles of inert minerals, such as sand, gravel, etc.

[0106] The fixed fibers that are needled through the granular layer hold the cover layer and the bottom layer at a certain distance from each other and are bonded to the cover layer and the bottom layer.

[0107] Short-fiber nonwovens, which are specifically considered for consolidation as a nonwoven fabric, also include filament nonwovens, meltblown nonwovens, and spunbond nonwovens, which typically require additional consolidation. Known possible consolidation methods for nonwovens include mechanical, thermal, and chemical consolidation. If mechanical consolidation is used, fibers are often held together purely mechanically by the entanglement of individual fibers, by the interconnection of fiber bundles into loops (Vermaschung), or by the stitching of additional threads. Adhesive (with adhesive) or cohesive (without adhesive) fiber-fiber bonds can be obtained thermally and chemically. Under suitable formulation and process control, these bonds can be limited to or at least primarily limited to fiber nodes, resulting in a stable three-dimensional network while still maintaining a relatively loose, open structure within the nonwoven fabric.

[0108] Nonwovens that have proven particularly advantageous are those that are secured by stitching together with individual threads or by forming loops with each other.

[0109] Such bonded nonwovens are manufactured, for example, on the “Malimo” type sewing machine from Karl Mayer (formerly Malimo), and are particularly available from Techtex GmbH. Malifleece (Malivlies) is characterized by bonding cross-laid nonwovens by forming loops from the fibers of the nonwoven fabric.

[0110] The carrier used can also be a Kunit or Multiknit type nonwoven fabric. Kunit nonwovens are characterized by their origin from processing longitudinally oriented fiber nonwovens to form a sheet-like structure with loops on one side and loop feet or pile fiber pleats on the other, but without yarn or a pre-fabricated sheet structure. This type of nonwoven has been manufactured for a considerable time, for example on the "Malimo" type stitching machine from Karl Mayer. A further characteristic of this nonwoven is its ability to absorb high tensile forces in the longitudinal direction, as a longitudinal fiber nonwoven. In contrast to Kunit nonwovens, Multiknit nonwovens are characterized by reinforcement on both the top and bottom sides by double-sided needle punching. The starting material for Multiknit is generally one or two single-sided interconnected loop pile fiber nonwovens manufactured using the Kunit process. In the final product, the two top sides of the nonwoven fabric are shaped to form a closed surface by means of interconnected looped fibers, and are connected to each other by fibers placed almost vertically. Another possibility is the introduction of additional sewn sheet-like structures and / or scatterable media.

[0111] Finally, stitch-bonded nonwovens are also suitable as intermediate products for forming tapes. Stitch-bonded nonwovens are formed from nonwoven materials with a large number of threads extending parallel to each other. These threads are formed by stitching or sewing together continuous textile threads. For this type of nonwoven (also known as Maliwatt), the "Malimo" type stitch-bonding machine from Karl Meyer is known.

[0112] Needle-punched felt nonwovens are also suitable. In needle-punched felt nonwovens, fiber tufts are formed into sheet-like structures using needles with barbs. The material is secured to the needle bar by the alternating introduction and withdrawal of the needles, with individual fibers looping together to form a robust sheet-like structure. The number and arrangement of the needle points (needle shape, penetration depth, double-sided needle punching) determine the thickness and strength of the fiber structure, which is typically lightweight, breathable, and elastic.

[0113] Another advantage is short-fiber nonwovens, which are mechanically pre-consolidated in the first step, or wet-laid nonwovens laid by hydraulic laying, wherein 2% to 50% by weight of the nonwoven fibers, and more particularly 5% to 40% by weight of the nonwoven fibers, are fusible fibers.

[0114] This nonwoven fabric is characterized by wet-laying of fibers, or, for example, pre-consolidating short-fiber nonwoven fabrics as follows: forming loops from the fibers of the nonwoven fabric by needle punching, sewing, air jetting and / or water jetting.

[0115] In the second step, heat setting is performed, in which the strength of the nonwoven fabric is further enhanced by melting or partially melting the fusible fibers.

[0116] Alternatively, the carrier can be compacted by calendering on a roller mill. The two rollers preferably run in opposite directions and at the same circumferential speed, thus pressing and compacting the carrier.

[0117] If there are differences in the circumferential speed of the rollers, the carrier will be polished separately.

[0118] The carrier is preferably a woven fabric, and more preferably a woven polyester fabric.

[0119] Especially preferred are woven fabrics having the following structure:

[0120] • The number of threads in the warp is 10 to 60 / cm.

[0121] • The number of threads in the weft yarn is 10 to 40 / cm.

[0122] • The warp yarn has a yarn weight of 40 to 400 dtex, more particularly 44 to 330 dtex, and very preferably 167 dtex.

[0123] The weft yarn has a yarn weight of 40 to 660 dtex, more preferably 44 to 400 dtex, and very preferably 167 dtex.

[0124] According to a further advantageous embodiment of the invention, the number of threads in the warp is 40 to 50 / cm, preferably 44 / cm.

[0125] According to a further advantageous embodiment of the invention, the yarn count in the weft yarn is 18 to 22, preferably 20.

[0126] According to a further advantageous embodiment of the invention, the woven fabric is a woven polyester fabric. Further possibilities include woven polyamide fabrics, woven viscose fabrics, and / or woven blended fabrics made from the aforementioned materials.

[0127] More preferably, the thickness of the woven fabric is at most 300 μm, more preferably 170 to 230 μm, and very preferably 190 to 210 μm.

[0128] According to another advantageous embodiment of the invention, the carrier has a maximum strength of 200 g / m³. 2 Preferred concentration: 100 to 150 g / m 2 Basis weight (weight per unit area).

[0129] The starting materials for the carrier material used in adhesive tapes are more particularly (man-made) fibers (short fibers or continuous filaments) made from synthetic polymers, also known as synthetic fibers, made from polyester, polyamide, polyimide, aramid, polyolefin, polyacrylonitrile, or glass; (man-made) fibers made from natural polymers such as cellulose fibers (viscose fiber, modal fiber, lyocell fiber, cuprammonium fiber, acetate fiber, triacetate fiber, celluloid), such as rubber fibers, such as plant protein fibers and / or such as animal protein fibers and / or natural fibers made from cotton, sisal, flax, silk, hemp, sesame, coconut, or wool. However, the invention is not limited to the materials described above; rather, it will be apparent to those skilled in the art that a variety of further fibers can be used to manufacture the carrier without requiring inventive steps.

[0130] In addition, yarns made of specified fibers are equally suitable.

[0131] In the case of woven fabrics or loosely woven cloth, individual yarns can be made from blended yarns, thus having both synthetic and natural components. However, generally, warp and weft yarns are formed from separate types.

[0132] Here, the warp and / or weft yarns may, in their respective cases, consist of only synthetic yarns or only yarns made from natural raw materials—in other words, of a single kind.

[0133] The yarns or threads used to weave the fabric may be in the form of filaments (filaments). For the purposes of this invention, a filament refers to a bundle of parallel, straight, single linear fibers / filaments, often referred to in the literature as multifilaments. This fiber bundle may optionally be given inherent reinforcement by twisting, and is then referred to as spun, folded, or twisted filaments. Alternatively, the fiber bundle may be given inherent reinforcement by entanglement using compressed air or water jets. In the following, for all these embodiments, the term "filament" will be used only in a generalized manner.

[0134] The silk can be textured or flat, and can have point reinforcement or no reinforcement.

[0135] In the context of this invention, the general term "tape" encompasses all sheet-like structures, such as two-dimensionally extended foils or foil portions (segments), strips having an extended length and a finite width, strip portions, etc., and finally, die-cut pieces (stamped pieces) or labels.

[0136] Therefore, the tape has a longitudinal range and a transverse range. The tape also has a thickness extending perpendicular to both ranges, wherein the transverse and longitudinal ranges are several times larger than the thickness. The thickness is made as uniform as possible, preferably exactly the same, across the entire surface of the tape defined by its length and width.

[0137] Adhesive tape exists specifically in the form of webs. A web is an object whose length is several times greater than its width, wherein the width is approximately and preferably uniform along its entire length.

[0138] Tape can be manufactured in roll form, in other words, wound around itself in the form of an Archimedean spiral.

[0139] The backing varnish applied to the back of the tape can have a favorable effect on the unwinding (unwinding) properties of the tape wound into an Archimedean spiral. For this purpose, the backing varnish may be formulated with a silicone compound or a fluorosilicone compound, and may also be formulated with polyvinyl stearyl urethane, polyethylene imide stearyl urea, or an organofluorine compound as an anti-sticking agent.

[0140] Dispersed adhesives can be applied in strips along the longitudinal direction of the tape, with the strip width being smaller than the width of the tape carrier.

[0141] Depending on the application, multiple parallel strips of the dispersion adhesive can also be coated onto the carrier material.

[0142] The position of the strip on the carrier is freely selectable, with the preferred placement being the strip directly at one edge of the carrier.

[0143] The dispersion adhesive is preferably applied to the entire area of ​​the carrier.

[0144] At least one strip of covering material may be provided on the adhesive coating of the carrier, the strip of covering material extending in the longitudinal direction of the tape and covering 20% ​​to 90% of the adhesive coating.

[0145] The strip is preferably covered with an adhesive coating covering 50% to 80% of the total area. The coverage level is selected based on the application and the diameter of the cable bundle.

[0146] The indicated percentage figures refer to the width of the strip of covering relative to the width of the carrier.

[0147] According to a preferred embodiment of the invention, there is exactly one strip of covering on the adhesive coating.

[0148] The invention is described with reference to working embodiments and accompanying drawings. The drawings illustrate:

[0149] Figure 1 A cross-sectional view of an apparatus for implementing the tape manufacturing method of the present invention is shown, and

[0150] exist Figure 1 The cross-sectional view schematically depicts an apparatus for applying an adhesive layer 8 to a fabric carrier 2. The apparatus includes a coating roller 3 on which the fabric carrier 2 deflects. The coating roller 3 is connected to a motor that rotates the coating roller 3 and advances the fabric carrier 2 along a feed direction V. The direction of rotation is variable.

[0151] In addition to the coating roller 3, there is also a double-slot die 4. The coating roller 3 and the double-slot die 4 have the same longitudinal range in their longitudinal direction L, which is perpendicular to the drawing plane. Here, the two equally long slots of the double-slot die 4 have a longitudinal range of 1600 mm. Other lengths are of course possible.

[0152] The double-slot die 4 and the coating roller 3 are arranged parallel to each other. They are preferably spaced a certain distance apart, forming a slot 6 of constant width between them through which the fabric carrier 2 is guided. During the coating operation, the fabric carrier 2 is pulled through the slot 6 and around the coating roller 3 (in... Figure 1(From lower right to upper right) Deflection. During the coating operation, the (ASE) thickener-water mixture 7 is first applied to the side of the fabric carrier 2 away from the coating roller 3 through the first slot die 7a. The (ASE) thickener-water mixture 7 has been prepared in advance in a mixing tank. Here, water is present in excess, so that the thickener is saturated and no further water is bound. The height of the first slot die 7a is about 100 μm, preferably exactly 100 μm. The length of the first slot die 7a is 1600 mm.

[0153] A second slot die 8a, continuously arranged in the feed direction V of the fabric carrier 2, allows the application of the dispersion adhesive 8 onto the thickener 7 already applied to the adhesive side 2a of the fabric carrier 2. The second slot die 8a also has a length of 1600 mm and a height of 300 μm. The (ASE) thickener-water mixture 7 is applied to the fabric carrier 2 in the form of a thickener layer, and the adhesive dispersion 8 is applied to the fabric carrier 2 in the form of a dispersion adhesive layer.

[0154] The viscosity of the (ASE) thickener-water mixture 7 is higher than that of the adhesive dispersion 8; that is, the viscosity of the adhesive dispersion 8 is η = 10 Pa*s, while the viscosity of the (ASE) thickener-water mixture 7 is η = 60 Pa*s. An acrylic adhesive diluted with water is applied as the adhesive dispersion 8. (70 g / m³) 2 The coating weight of adhesive dispersion 8 is applied. The fabric carrier 2 used is PET nonwoven fabric. (ASE) Thickener-water mixture 7 has been applied at 2 g / m 2 The coating is applied by weight onto the PET nonwoven fabric. The thickener used is Sera Print M-PHC. First, the (ASE) thickener-water mixture 7 immediately sinks into the fabric carrier 2 during coating. Only a few microseconds after the application of the (ASE) thickener-water mixture, the applied adhesive dispersion sinks only a small amount into the carrier 2 due to the thickener layer. A drying device (not shown here) is arranged downstream of the coating roller 3 in the feed direction V, which dries the applied adhesive layer 8 and thickener layer 7 to provide the finished tape 1.

[0155] List of reference numerals

[0156] 1. Adhesive tape

[0157] 2 Fabric carrier

[0158] 2a Adhesive side

[0159] 3 Coating rollers

[0160] 4. Double-slot die head

[0161] 6. Slot

[0162] 7. Thickener

[0163] 7a First slot die head

[0164] 8. Adhesive dispersions

[0165] 8a Second slot die head

[0166] L (vertical direction)

[0167] V Feed direction

Claims

1. Process for manufacturing an adhesive tape comprising the following steps: a) mixing a thickener with water and producing a thickener-water mixture (7); b) producing an adhesive dispersion (8) from an adhesive and a solvent; c) providing a fabric carrier (2); d) applying the thickener-water mixture (7) to the fabric carrier; e) applying the adhesive dispersion (8) to the thickener-water mixture (7) to obtain an adhesive tape; f) drying the obtained adhesive tape, characterized in that In the thickener-water mixture (7) water is present in excess so that the thickener is saturated with water, and the application of the adhesive dispersion (8) is carried out after or synchronously with the application of the thickener-water mixture (7).

2. The method of claim 1, wherein, The thickener is an ASE thickener.

3. The method of claim 1, wherein, The weight ratio of water to thickener is 1 : 1 to 10:

1.

4. The method of claim 3, wherein, The weight ratio of water to thickener is 1 : 1 to 5:

1.

5. The method of claim 3, wherein, The weight ratio of water to thickener is 1 : 1 to 2:

1.

6. The method of any one of claims 1 to 5, wherein, The thickener-water mixture (7) comprises 5 to 25 wt% of the same adhesive which is also present in the adhesive dispersion (8).

7. The method of claim 6, wherein, The thickener-water mixture (7) comprises 10 to 20 wt% of the same adhesive which is also present in the adhesive dispersion (8).

8. The method of any one of claims 1 to 5, wherein, The adhesive dispersion (8) comprises up to 20 wt% of the thickener.

9. The method of claim 8, wherein, The adhesive dispersion (8) comprises up to 10 wt% of the thickener.

10. The method of claim 8, wherein, The adhesive dispersion (8) comprises up to 5 wt% of the thickener.

11. The method of any one of claims 1 to 5, wherein, An ASE or HASE thickener is used as the thickener.

12. The method according to any one of claims 1 to 5, characterized in that, The thickener-water mixture (7) is applied on the entire area of the fabric carrier (2).

13. The method according to any one of claims 1 to 5, characterized in that, The adhesive dispersion (8) is applied on the entire area.

14. The method of claim 13, wherein, The adhesive dispersion (8) is applied to the thickener-water mixture (7) on the entire area.

15. The method of claim 14, wherein, The thickener-water mixture (7) is an ASE thickener-water mixture.

16. The method according to any one of claims 1 to 5, characterized in that, A double slot die (4) is used for applying the thickener-water mixture (7) and the adhesive dispersion (8).

17. The method of any one of claims 1 to 5, wherein, dispersion adhesives having a viscosity of 0.2 Pa s to 15 Pa s ± 5 Pa s 18. The method of claim 17, wherein, dispersion adhesives having a viscosity of 2 to 5 Pa s.

19. The method of any one of claims 1 to 5, wherein, The thickener-water mixture (7) has a higher viscosity than the adhesive dispersion (8).

20. The method of any one of claims 1 to 5, wherein, A polymer dispersion is used as dispersion adhesive, wherein the polymer is constructed from: - 95.0 to 100.0 wt% of n-butyl acrylate and / or 2-ethylhexyl acrylate - 0.0 to 5.0 wt% of an olefinically unsaturated monomer with acid or anhydride functionality.

21. The method of any one of claims 1 to 5, wherein, A water-soluble polyacrylic acid and a polycoacrylic acid are used as thickener.

22. The method of any one of claims 1 to 5, wherein, A knitted fabric, a scrim, a tape, a braid, a needle-punched textile, a felt, a woven fabric or a nonwoven is used as the fabric carrier (2).

23. The method of claim 22, wherein, Maliwatt is used as the fabric carrier (2).

24. The method of claim 16, wherein, A double slot die (4) with a slot width of 100 to 300 pm is used.

25. The method of any one of claims 1 to 5, wherein, The dried adhesive tape is wound into a roll.

26. The method of any one of claims 1 to 5, wherein, The adhesive dispersion has a solids content of 10 to 70 wt% adhesive.

27. The method of claim 26, wherein, The adhesive dispersion has a solids content of 50 to 60 wt% adhesive.

28. The method of claim 26, wherein, The thickener layer has a solids content of 10 to 20 wt% adhesive.

29. The method of claim 16, wherein, The thickener-water mixture and the adhesive dispersion are applied through two slot dies arranged in series.

30. The method of claim 20, wherein, The polymer consists of 95.0 to 99.5 % by weight of n-butyl acrylate and / or 2- ethylhexyl acrylate and 0.5 to 5 % by weight of an olefinically unsaturated monomer having an acid or anhydride functionality.

31. The method of claim 20, wherein, The polymer consists of 98.0 to 99.0 % by weight of n-butyl acrylate and / or 2- ethylhexyl acrylate and 1.0 to 2.0 % by weight of an olefinically unsaturated monomer having an acid or anhydride functionality.

32. The method of claim 20, wherein, The polymer consists of: (a) 95.0 to 100.0 % by weight of n-butyl acrylate, and (b) 0.0 to 5.0 % by weight of acrylic acid.

33. The method of claim 2, wherein, The viscosity of the ASE thickener is η = 15 to 100 Pa -1 s at a shear rate of 10 s -1.

34. The method of claim 22, wherein, The carrier is a woven fabric.

35. The method of claim 34, wherein, The carrier is a woven polyester fabric.

36. The method of claim 34, wherein, The carrier is a woven fabric having the following construction: • the thread count in the warp is 10 to 60 / cm, • the thread count in the weft is 10 to 40 / cm, • the warp threads have a thread weight of 40 to 400 dtex, • the weft threads have a thread weight of 40 to 660 dtex.

37. The method of claim 36, wherein, The thread count in the warp is 40 to 50 / cm.

38. The method of claim 36, wherein, The thread count in the weft is 18 to 22 / cm.

39. The method of any one of claims 1 to 5, wherein, The carrier has a basis weight of up to 200 g / m 2 .

40. The method of claim 39, wherein, The carrier has a basis weight of 100 to 150 g / m 2 .

41. The method of any one of claims 1 to 5, wherein, The thickener-water mixture is applied immediately before the aqueous dispersion adhesive.

42. The method of claim 41, wherein, The time difference is 0.1 ms to 100 s when wet-on-wet coating is carried out in one operation.

43. The method of claim 42, wherein, The time difference is 0.1 ms when a double die is used.

44. The method of claim 42, wherein, The time difference is 100 s when a second separate coating system is used.

45. The method of claim 42, wherein, The time difference is 0.5 ms to 20 s.

46. The method of claim 42, wherein, The time difference is 1 ms to 10 s.

47. The method of claim 42, wherein, The time difference is 1 ms to 10 ms.

48. The method of any one of claims 1 to 5, wherein, The thickener-water mixture and the aqueous dispersion adhesive are applied simultaneously.

49. The method of claim 16, wherein, The double slot die has a slot width, also referred to as height, of 20 to 700 pm and a length corresponding to the width of the fabric carrier.

50. The method of claim 49, wherein, The double slot die has a slot width of 50 to 500 pm.

51. The method of claim 49, wherein, The length is 10 to 4000 mm.

52. The method of claim 49, wherein, The length is 1000 to 2000 mm.

53. The method of claim 16, wherein, The fabric carrier is guided around the coating roll and rests on the coating roll with a side facing away from the application side and is pushed forward by the rotational movement of the coating roll.

54. The method of claim 16, wherein, A double slot die is arranged at the adhesive side of the fabric carrier, where the feed rate of the fabric carrier and the slot pitch of the double slot die are selected such that the application of the thickener-water mixture to the fabric carrier is followed by the application of the adhesive dispersion on the thickener-water mixture only 1 to 10 ms later.

55. Adhesive tape obtainable by the method of any one of claims 1 to 54.

56. Device for carrying out the method of any one of claims 1 to 54, comprising a coating roll having a longitudinal coating roll direction and a double slot die having a longitudinal slot direction, the double slot die being arranged along the longitudinal coating roll direction.

57. The apparatus of claim 56 wherein, The two longitudinal directions are arranged parallel to each other.

58. The apparatus of claim 56, wherein, The first and second slot dies are arranged on one side of the fabric carrier.

59. The apparatus of claim 56, wherein, A free spacing is provided between the double-slot die and the coating roller, which free spacing forms a slot through which the fabric carrier is fed.

60. The apparatus of claim 59 wherein, The fabric carrier is deflected around the coating roller and advanced by the coating roller or another device.

61. The apparatus of claim 59 wherein, The feed direction of the fabric carrier is arranged transversely to the longitudinal direction of the coating roller and / or the double-slot die.

62. The apparatus of claim 59, wherein, The feed direction of the fabric carrier is arranged perpendicularly to the longitudinal direction of the coating roller and / or the double-slot die. The feed direction of the fabric carrier is arranged perpendicularly to the longitudinal direction of the coating roller and / or the double-slot die.

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