Die-cut parts specifically for permanently sealing holes

Abstract

This invention relates to die-cut parts, particularly for permanently sealing holes, especially holes in metal sheets or plastic parts, said die-cut parts comprising a carrier consisting of components, particularly a laminate in a specified layer sequence: at least one first layer formed of a needle-punched nonwoven fabric having a thickness of 1 to 6 mm, wherein said needle-punched nonwoven fabric contains mechanically needle-punched, oxidized, and heat-stable polyacrylonitrile (PAN) fibers; optionally at least one second layer formed of a pressure-sensitive adhesive material in the form of a lamination adhesive, particularly having a thickness of 5 to 50 g / m². 2 Weight is applied per unit area; at least one third layer, which consists of a weight of 30 to 200 g / m². 2 The base layer is formed of a glass-woven fabric or glass-laid fabric; optionally, at least one fourth layer is formed of a pressure-sensitive adhesive material in the form of a laminated adhesive, particularly having an applied weight per unit area of ​​5 to 50 g / m²; at least one fifth layer is formed of a metal layer having a thickness of 5 to 40 μm; and at least one sixth layer is formed of an additional acrylate-based pressure-sensitive adhesive material having a weight per unit area of ​​300 to 1800 g / m². 2 Preferred weight is 360 to 1500 g / m³. 2 The basis weight, and / or the thickness of 400 to 1800 μm, preferably 800 to 1500 μm.

Description

[0001] The present invention relates to die-cut parts, particularly for permanently sealing (closing) openings such as holes, preferably located in metal plates or plastic parts (particularly vehicles), and to methods for permanently sealing holes.

[0002] When constructing relatively complex structures from sheet metal and / or plastic, the construction requirements make it unavoidable to cut holes in the sheets or plastic to access cavities located behind them, whether for painting or welding purposes.

[0003] After the necessary operations are completed, these holes are usually no longer needed, and they are often even destructive because air, atmospheric moisture, or water can pass through them into the structure, which can lead to processes such as oxidation (rusting).

[0004] A simple solution to avoid these problems is to seal the hole again after use.

[0005] Especially in the production of modern transportation vehicles such as ships, land vehicles (trucks, cars, etc.), aircraft, spacecraft, and their combinations (e.g., amphibious vehicles), the following is unavoidable: during assembly, holes of different sizes are required in many individual components made of sheet metal or plastic. The hole diameter is typically between 5 and 50 mm. In subsequent operations, many of these holes must be sealed again airtightly and, especially, watertightly to prevent corrosive attack (erosion).

[0006] Another requirement is to achieve a significant improvement in sound insulation inside the carriage by sealing the holes.

[0007] The following uses a car body as an example to describe the problem behind the invention and its solution. Clearly, this does not limit the concept of the invention to this application. This application is part of the technical field in which the invention demonstrates particular advantage.

[0008] If we refer to its use in the vehicle body (the main body of a vehicle) from now on, technicians will consider it to include the vehicle body as well as all other possible uses.

[0009] In automobile manufacturing, holes must be manufactured or stamped at various locations within the body. This is typically accomplished through stamping and forming operations on individual sheet metal or aluminum parts; alternatively, holes may be drilled into plastic parts. Subsequently, these individual metal parts are joined together using various joining processes to form the body shell. The holes, openings, or channels in this body shell serve, in particular, as: paint drainage holes (e.g., for cathodic electrocoating materials (KTL-Lacke)), wax injection holes, wax drainage holes, holes for screw mounting operations during subsequent assembly, or cable channels. Many of these holes must be resealed after the cathodic electrocoating material dries, or after the final clear coat application (in this case, hole sealing occurs during assembly).

[0010] There are many possible reasons why a hole needs to be sealed, for example:

[0011] -Moisture

[0012] -acoustics

[0013] - Corrosion protection.

[0014] Generally, holes or openings are sealed using injection-molded parts (stoppers) made of various plastics manufactured according to requirements. These can be stoppers made of, for example, PET, ABS, PP, PVC, EPDM, PA, and other commercial plastics, or combinations of the aforementioned materials and conventional commercial polymer substrates not listed herein. Materials with glass fiber components are also used; carbon fiber, for example, is also conceivable, which reinforces the stopper to prevent it from being pushed out. In principle, all common polymer substrates are possible, provided they provide specific parameters related to paintability, temperature stability, and dimensional stability under climatic conditions, and also meet certain economic requirements in the stopper manufacturing process.

[0015] Currently, vehicle body openings are typically sealed with plastic plugs. However, in certain situations, these plugs fail to seal the openings securely, and their manufacture is relatively complex and expensive.

[0016] Each hole size requires a specific plug to fit that hole size. This necessitates significant logistical and administrative labor for the plug users. Consequently, a large number of plugs of different sizes must be housed in correspondingly allocated storage bins on the production line.

[0017] Another suitable option for this purpose is tape, which is cut or die-cut to length according to the hole size. However, tape cannot always meet the ever-increasing market demands.

[0018] The intention here is to pay closer attention to the self-adhesive hole closures required to achieve the acoustic effects.

[0019] These acoustically relevant perforated closures are often used in assembly to create an isolated area within the passenger compartment, i.e., the vehicle interior. For example, destructive sounds can arise inside the vehicle from tire rolling noise or from loose gravel and debris thrown against vehicle panels and structural components. Furthermore, wind noise, a result of non-streamlined design, is another possible cause of relatively high, undesirable noise levels within the passenger compartment.

[0020] Noise from loose gravel, debris, tire rolling noise, and uneven ground is often transmitted into cavities within the structural component system (lateral and transverse members) and into the vehicle interior or passenger compartment. Therefore, acoustically effective products must also be used on the exterior of the vehicle. For example, one form of effective acoustic protection is to seal holes in the floor assembly or vehicle frame with tape. Holes are often made, punched, or drilled in the lateral and transverse members. Special care must be taken to carefully seal every possible opening.

[0021] As already described, numerous orifices in sheet metal body components or structural member systems are designed to allow cathodic electrocoating material to drain from the body and from all kinds of cavities as quickly as possible to ensure operating time. Conversely, this means that openings and orifices must be reliably sealed immediately downstream of the cathodic electrocoating dryer. This is typically done on so-called PVC lines. This area involves manufacturing steps performed before the application of primer-second primer or before the application of topcoat. Therefore, another characteristic to be satisfied is the repaintability of the product used in this production section (stage). In addition, it must be compatible with PVC joint sealant, as the gap between the cathodic electrophoretic coating dryer and the next coating layer is sealed with pumpable PVC material.

[0022] Hole-sealing products based on heavy-duty membranes combined with a membrane applied to the top side are known from EP 3 036 100 A1. Disclosed therein are die-cut parts specifically for permanently sealing holes, particularly in metal sheets or plastic parts, the die-cut part having a carrier consisting of a laminate comprising at least two polymer films, wherein the lower film has a density of at least 1.5 kg / m³. 2 More specifically at 1.5 and 6 kg / m 2 The lower membrane carries the applied adhesive, more particularly a curable or self-adhesive adhesive, on the side opposite to the upper membrane. The upper membrane is preferably composed of polyester, more preferably of polyethylene terephthalate (PET).

[0023] In addition to traditional vehicles with internal combustion engines, hybrid electric vehicles (HEVs) and battery electric vehicles (BEVs) are becoming increasingly important.

[0024] A hybrid electric vehicle (HEV) is a vehicle that uses a hybrid powertrain; in other words, it is powered by at least one electric motor and an additional energy converter, drawing energy from both its battery and additional fuel. A fully electric vehicle (EV) is powered solely by a battery-powered electric motor and therefore requires no fossil fuels. The battery is charged via an external network component.

[0025] The problem with these vehicles is the battery, such as a lithium-ion battery, located in the main body. A burning lithium-ion battery is much harder to extinguish than a burning gasoline or diesel vehicle.

[0026] Therefore, there are continuously increasing safety requirements for managing batteries in electric vehicles. OEMs are trying to ensure, to the greatest extent possible, that fire is prevented from spreading from the battery compartment into the vehicle through openings in the body, for example. Since there are no precise specifications for flame temperature or penetration time, the solutions used primarily cover those that encompass the maximum possible temperature range and time span.

[0027] The initial product can provide the ability to meet the stringent requirements imposed.

[0028] From tesa SE 54332 combines an extremely heat-resistant carrier composed of an aluminum and glass fiber woven fabric with an ultra-thick acrylic adhesive. This product is optimized for use in automotive manufacturing to seal unused body openings where excellent heat resistance and perfect sealing are required. The product withstands a horizontal (layout) burning (fireproofing) test at temperatures up to 500°C for at least 5 minutes. This test determines the flame penetration time at the corresponding temperature. The construction and implementation of the burning test are described in detail below.

[0029] GTR 20 (Global Technical Specification No. 20), as of May 3, 2018, outlines the current fire resistance requirements imposed on BEVs, such as those related to the battery pack. OEMs / OES are also attempting to provide maximum fire resistance to surrounding components, such as die-cut parts in the underbody.

[0030] The object of the present invention is to provide a die-cut part that is suitable for permanently sealing holes, particularly holes in metal panels or plastic parts of a vehicle body, and that seals the holes in such a way that moisture penetration is impossible; that can be repainted with at least some of the conventional paint; that enhances sound insulation and provides a reliable seal against mechanical exposure internally, particularly in the underbody area; and that provides improved resistance to heat and fire.

[0031] This objective is achieved by die-cutting as specified in the independent claim. The dependent claims provide advantageous further developments into the subject matter of the invention.

[0032] Therefore, the present invention provides die-cut parts, particularly for permanently sealing holes, especially in metal sheets or plastic parts, the die-cut parts having a carrier composed of components, more particularly laminates, the components, more particularly laminates being composed of the following in a specified layer sequence: optionally at least one first layer (also referred to as layer A) is formed of a needle-punched nonwoven fabric (Nadelvlies, needle-punched felt web) having a thickness of 1 to 6 mm, wherein the needle-punched felt web comprises mechanically needle-punched, oxidized, and heat-stabilized polyacrylonitrile (PAN) fibers; optionally at least one second layer, the at least one second layer being formed of a laminating adhesive having a particularly high g / m² content of 5 to 50 g / m². 2 A pressure-sensitive adhesive is formed by coating a unit area of ​​weight; at least one third layer (also referred to as layer B), said at least one third layer being composed of a coating weight of 30 to 200 g / m². 2 The base layer is formed of woven or laid glass fabric; optionally, at least one fourth layer is formed of a laminated adhesive having a specific strength of 5 to 50 g / m². 2 The coating consists of a pressure-sensitive adhesive layer formed by coating a unit area of ​​weight; at least one fifth layer (also referred to as layer C), said at least one fifth layer being formed of a metal layer having a thickness of 5 to 40 μm; and at least one sixth layer (also referred to as layer D), said at least one sixth layer being formed of a metal layer having a thickness of 300 to 1800 g / m². 2 Preferred weight is 360 to 1500 g / m³. 2 The basis weight and / or an additional pressure-sensitive adhesive with a thickness of 400 to 1800 μm, preferably 800 to 1500 μm, are formed.

[0033] Therefore, the die-cut part includes at least a first, third, fifth, and sixth layer. A preferred embodiment of the die-cut part is wherein at least the first, second, third, fourth, fifth, and sixth layers are present simultaneously.

[0034] The first layer having a thickness of at least 1 mm to 6 mm, more preferably 2 mm to 4 mm, more preferably 3 mm, is formed of a needle-punched nonwoven fabric, wherein the needle-punched nonwoven fabric comprises mechanically needle-punched, oxidized, and thermally stable polyacrylonitrile (PAN) fibers (Preox fibers).

[0035] More preferably, the needle-punched nonwoven fabric has a density of 600 to 1200 g / m². 2 More preferably 700 to 100 g / m 2 More preferably 800 to 900 g / m 2 The base weight.

[0036] For needle-punched nonwovens, fiber clusters are formed into sheet-like structures using barbed needles. The material is secured to the needle bar by alternately introducing and withdrawing the needles, with individual fibers looping together to form a robust sheet-like structure. The number and configuration 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.

[0037] Details about needle-punched nonwovens can be found in particular in the book “Vliesstoffe-Rohstoffe, Herstellung, Anwendung, Eigenschaften, Prüfung” [Nonwovens-Raw materials, Production, Use, Properties, Testing], Hilmar Fuchs, Wilhelm Albrecht (ed.), 2nd edition, Wiley-VCHVerlag, Weinheim 2012.

[0038] The basic structural unit of polyacrylonitrile (PAN) is acrylonitrile (AN). PAN is a semi-crystalline thermoplastic whose crystallization sequence is generated by the periodic arrangement of chain molecules and is therefore dependent on the processing of the material. In its homopolymer form, PAN has a melting point above its decomposition temperature, meaning that PAN is not meltable under normal conditions. During the polymerization of acrylonitrile, comonomers can be introduced into the polymer, which critically determine the processability of the fiber and therefore also the properties of the final fiber. In manufacturing, comonomers can increase the mobility of the PAN chains and thus support their orientation, resulting in higher fiber quality. In the following heat treatment steps, the properties and amount of comonomers determine the temperature at which the reaction begins, the amount of exothermic enthalpy released, and the achieved mass yield. The comonomer fraction is typically no more than 5 mol%, with the remainder being AN. Common comonomers used are methyl methacrylate (MMA) and itaconic acid (IA).

[0039] To convert PAN into fibrous form, it is first spun. Conventional melt spinning, where the melt is extruded through a spinning die, is only feasible with the use of large amounts of solvent and plasticizer. In this way, the melting point is sufficiently lowered, allowing PAN to melt before the cyclization reaction begins. A more feasible and therefore most common process is wet spinning. In this case, a PAN solution is injected into a precipitation bath, where the polymer precipitates. The solvent diffuses from the polymer solution into the coagulation bath. The kinetics of these processes depend primarily on the bath temperature and concentration gradient.

[0040] According to a preferred embodiment of the invention, the needle-punched nonwoven fabric comprises up to 80% by weight, more preferably up to 90% by weight, and even more preferably up to 95% by weight of polyacrylonitrile (PAN) fibers.

[0041] According to a particularly preferred embodiment of the invention, the needle-punched nonwoven fabric is composed of polyacrylonitrile (PAN) fibers (100% by weight).

[0042] Other fibers may consist of glass, carbon, a combination of two types of fibers, aromatic polyamide fibers or polyamide, oriented polymer fibers such as polyester fibers such as polyethylene terephthalate, polypropylene fibers, and polyethylene fibers.

[0043] The fibers preferably have a fiber thickness of 2 to 5 denier and / or a fiber length of 30 to 90 mm.

[0044] According to the invention, needle-punched nonwoven fabrics may contain flame retardants, preferably in an amount of at least 1% by weight and more preferably less than 10% by weight. It has been found that at such flame retardant content, there is no adverse effect or almost no adverse effect on the properties of the layer. In this invention, the lower the fraction of flame retardant in the layer, the better. The layer preferably contains less than 8% by weight, more preferably less than 6% by weight, and more particularly less than 3% by weight. In each case, these figures are based on the total weight of the layer.

[0045] Suitable flame retardants include, for example, alumina hydrate, zinc borate, ammonium phosphate and / or ammonium polyphosphate, antimony oxide, chlorinated paraffin, polychlorinated biphenyls, hexabromobenzene, and polybrominated diphenyl ethers; cyanurates such as melamine cyanurate; organophosphate derivatives such as 2-carboxyethyl-phenyl phosphate; organophosphates and polyphosphates, phosphites and phosphonates, such as tricresyl phosphate, tert-butylphenyl diphenyl phosphate, bisphenol A-bis(diphenyl phosphate), resorcinol bis(diphenyl phosphate), and melamine polyphosphate, diethylbis(2-hydroxyethyl)aminomethylphosphonate and diphenylaniline phosphonate; phosphonates, diphosphonates and dialkylphosphonates; and halogenated organophosphate compounds such as tris(2,3-dibromopropyl) phosphate, tris(2-bromo-4-methylphenyl) phosphate, and tris(2-chloroisopropyl) phosphate. Halogen-free flame retardants are preferred in this invention. Therefore, the flame retardants that can be used in this invention are preferably selected from alumina hydrate, zinc borate, ammonium phosphate and ammonium polyphosphate, antimony oxide; cyanurate; organophosphate derivatives; organophosphate esters, phosphites and phosphonates; phosphonates, dialkyl phosphonates and dialkyl phosphonates, and mixtures of two or more of the above flame retardants. More preferably, the flame retardants that can be used in this invention are selected from ammonium polyphosphate and dialkyl phosphonates.

[0046] The preferred dialkylphosphinates in this invention are those of formula F2.

[0047] (R III R IV (O)PO (-) ) m M (m+ (F2),

[0048] Where R III and R IV They are the same or different, and are straight-chain or branched C1 to C6 alkyl groups;

[0049] M is Mg, Ca, Al, Sb, Sn, Ge, Ti, Fe, Zr, Zn, Ce, Bi, Sr, Mn, Li, Na, K, or a protonated nitrogen base; and

[0050] m is a natural number from 1 to 4.

[0051] M is preferably Al, Ca, Ti, Zn, Sn, or Zr.

[0052] R III and R IV Preferably the same or different, and are methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, n-hexyl or isohexyl groups.

[0053] Particularly preferred dialkyl phosphonates are aluminum tri(diethyl)phosphonate, aluminum tri(methylethyl)phosphonate, aluminum tri(ethylbutyl)phosphonate, titanium bis(diethyl)phosphonate, titanium tetra(diethyl)phosphonate, titanium bis(methylethyl)phosphonate, titanium tetra(methylethyl)phosphonate, titanium bis(ethylbutyl)phosphonate, titanium tetra(ethylbutyl)phosphonate, zinc bis(diethyl)phosphonate, zinc bis(methylethyl)phosphonate and zinc bis(ethylbutyl)phosphonate, and mixtures of two or more of these dialkyl phosphonates.

[0054] In addition to the substances already mentioned, the flame retardant in this invention may include one or more substances called synergists. The synergist may be present in the flame retardant at 0.1 to 70% by weight, based on the total weight of the flame retardant. More preferably, the flame retardant includes...

[0055] a) 60 to 99% by weight of one or more compounds selected from dialkylphosphinates and ammonium polyphosphates of formula F2, and

[0056] b) 1 to 40% by weight of one or more synergists,

[0057] The fractions are based on the total weight of the flame retardants and are added together to reach 100% by weight.

[0058] The synergist is preferably a nitrogen, phosphorus, or a nitrogen and phosphorus compound. More preferably, the synergist is selected from: allantoin, cyanuric acid, glycyrrhizin, urea, melamine, melon, melonamine, melamine phosphate, melamine pyrophosphate, melamine polyphosphate, melonamine polyphosphate, melonamine polyphosphate, melamine polyphosphate, melamine cyanurate, piperazine phosphate, piperazine pyrophosphate, carbodiimide, sterically hindered phenol, phosphine oxide, hypophosphite (salt), cyclic phosphonate (salt), triaryl (alkyl) phosphite, alkyl and aryl substituted phosphate (salt), aluminum compounds, tin compounds, boron compounds, magnesium compounds, calcium compounds and cerium compounds, zinc oxide, zinc carbonate, zinc stannate, zinc borate, zinc hydrogen phosphate, zinc pyrophosphate, zinc oleate, zinc stearate and / or zinc phosphate.

[0059] When a flame retardant includes one or more synergists, they are considered part of the flame retardant in this invention. Therefore, if present, they are specifically included in the fraction of flame retardants mentioned in the preceding section.

[0060] The flame retardant can be introduced into the composition of the layer using conventional mixing equipment, such as a stirrer mechanism. Preferably, this introduction is performed before the layer in question is applied.

[0061] In addition, silicone-based additives can be added to support the effect of the flame retardant. Such additives are described, for example, in US 4,387,176 A.

[0062] The third layer of glass fabric, or the laying of glass fabric, advantageously possesses the following properties:

[0063] Basis weight at 60 and 120 g / m 2 Between 70 and 100 g / m 2 Between, and especially at 80 and 90 g / m 2 between.

[0064] The warp yarn count and / or weft yarn count are 3 to 50 yarns / cm in their respective cases.

[0065] According to another advantageous embodiment of the invention, the warp yarn count is 5-10 / cm, preferably 7 / cm and / or the weft yarn count is 4-10 / cm, preferably 5 / cm.

[0066] The line weight of the longitudinal and transverse lines is preferably 500 to 1000 dtex, more preferably between 600 and 800 dtex, and particularly preferably 680 dtex.

[0067] Lateral fineness is a term that multiplies the number of lateral threads (weft threads) per centimeter by the weight of the lateral threads in decitexes. The unit is decitexes / cm.

[0068] Longitudinal fineness is a term used to describe the number of warp threads per centimeter multiplied by the weight of the warp threads in decitexes. The unit is again decitexes / cm.

[0069] According to another advantageous embodiment of the invention, the longitudinal fineness of the longitudinal thread and / or the transverse fineness of the transverse thread is greater than 2000 dtex / cm. Preferably, the longitudinal fineness is between 4000 and 5000 dtex / cm and / or the transverse fineness is between 3000 and 4000 dtex / cm.

[0070] In the weaving of glass fabrics, the threads are woven in a plain weave. Other weave types are satin (also known as satin weave, which has regular and irregular patterns) and twill. Twill weave (e.g., "2 over 1 twill") produces so-called twill lines that extend diagonally opposite the direction of the machine.

[0071] A fabric is a sheet-like structure consisting of layers of one or more parallel, extended tension threads. These threads are typically secured at their intersections. Securing is accomplished either through material bonding (cohesive adhesion) or mechanically through friction and / or interlocking.

[0072] The following types of fabric fabric (fadengelegen) exist:

[0073] • Single-axis or unidirectional, formed by fixing a set of parallel lines.

[0074] • Biaxial, in which two sets of parallel lines are fixed in the directions of the two axes.

[0075] • Multi-axis: Multiple sets of parallel lines are fixed in the direction of different axes.

[0076] In the case of multi-layered fabric, the layers of thread can all have different orientations, and can also be composed of different linear densities and different linear densities (Fadenfeinheiten).

[0077] In this invention, a single-layer fabric is preferred.

[0078] According to an advantageous embodiment of the invention, the metal layer has a thickness of 8 to 20 μm, more preferably 10 to 12 μm. If necessary, it may also have an embossed pattern.

[0079] Optional metals include silver, copper, gold, platinum, aluminum and aluminum compounds, tin, nickel-chromium alloys, Nirosta, titanium, and metal oxides such as cadmium oxide, tin oxide, zinc oxide, and magnesium oxide. Aluminum is particularly preferred. This description should not be considered exhaustive; rather, those skilled in the art can choose other metal layers not explicitly stated herein without departing from the inventive concept.

[0080] The metallic layer preferably includes rolled metal foil, more particularly aluminum foil.

[0081] Further advantageously, according to the invention, the metallic layer used may comprise a layer of metal oxides (MeOx layer). Advantageous metal oxide layers are, for example, composed of silicon dioxide (SiO2), titanium dioxide (TiO2), or zinc tin oxide (ZnSnO), or may include one or more of these metal oxides.

[0082] Functional layers, such as adhesion promoters for improving composite material adhesion, may be present between the first layer made of needle-punched nonwoven fabric and the third layer in the form of glass-woven fabric or laid glass-woven fabric, and between the third layer in the form of glass-woven fabric or laid glass-woven fabric and the metal layer. A pressure-sensitive adhesive layer in the form of a laminated adhesive is preferred, and it particularly has a strength of 5 to 50 g / m³. 2 More specifically, 7 to 20 g / m 2 The coating weight per unit area.

[0083] Another possibility is that a first layer made of needle-punched nonwoven fabric and a third layer in the form of woven or laid glass fabric, as well as a third layer in the form of woven or laid glass fabric and a metal layer, are bonded together under pressure by lamination.

[0084] More preferably, the woven or laid glass fabric is located in a polymer layer, such as a polyurethane-based polymer layer, such that all the filaments of the woven or laid glass fabric are surrounded by the polymer as completely as possible.

[0085] Preferably, for this purpose, the woven or laid glass fabric is introduced into the still viscous polymer, causing the polymer to flow around the woven or laid glass fabric, or the polymer is poured onto the woven or laid glass fabric, causing the polymer to flow around the woven or laid glass fabric.

[0086] Suitable laminating adhesives include pressure-sensitive adhesives, as fully described below.

[0087] All known adhesive systems can be used. In addition to adhesives based on natural or synthetic rubber, silicone adhesives and polyacrylate adhesives can be used in particular.

[0088] The two adhesive layers are applied in the same manner, but they can be chosen to be different as needed.

[0089] The corresponding coating weights can be different or the same.

[0090] The adhesive is preferably a pressure-sensitive adhesive (PSA), which allows for durable adhesion to virtually all substrates even under relatively weak applied pressure and can be re-separated from the substrate with virtually no residue after use. The PSA is permanently tacky at room temperature and therefore has sufficiently low viscosity and high initial tack to wet the surface of the corresponding substrate, even under low applied pressure. The adhesiveness of the adhesive derives from its adhesive properties, and its re-separability derives from its cohesive properties.

[0091] PSA can be considered a highly viscous liquid with an elastic component (part). Therefore, they possess specific characteristic viscoelastic properties, resulting in permanent inherent viscosity and adhesiveness.

[0092] PSAs are characterized by a viscous flow process and the formation of elastic rebound forces when they are mechanically deformed. These two processes are related to each other in their respective proportions, depending not only on the precise composition, structure, and degree of cross-linking of the corresponding PSA, but also on the rate and duration of deformation, as well as the temperature.

[0093] Proportional (certain) viscous flow is necessary for adhesion. The viscous component (part) brought about solely by macromolecules with relatively high mobility allows for effective wetting of the substrate to be bonded and efficient flow onto it. High viscous flow components result in high pressure-sensitive adhesive tack (also known as tack or surface tack) and therefore often also high peel adhesion. Due to the lack of flowable components, highly cross-linked systems and polymers (which are crystalline or have undergone glassy curing) generally possess at least very little tack or none at all.

[0094] Proportional (specific) elastic resilience is necessary to achieve cohesion. This is embodied, for example, by very long chains of macromolecules with high coiling and by macromolecules that are physically or chemically cross-linked, and it allows the transmission of forces acting on the adhesive bond. As a result of these resilience forces, the adhesive bond is able to withstand long-term loads (in the form of long-term shear loads), for example, sufficiently over a relatively long period of time.

[0095] All known adhesive systems can be used here. In addition to adhesives based on natural or synthetic rubber, silicone adhesives and polyacrylate adhesives, preferably low molecular weight acrylate hot melt pressure-sensitive adhesives, are particularly suitable.

[0096] The preferred adhesive is an acrylate- or silicone-based adhesive.

[0097] The adhesive may be selected from natural rubber or synthetic rubber, or any desired blend of natural rubber and / or synthetic rubber, wherein, depending on the required purity and viscosity level, natural rubber may in principle be selected from all available grades, such as crepe, RSS, ADS, TSR or CV products, and synthetic rubber may be selected from: random copolymers of styrene-butadiene rubber (SBR), butadiene rubber (BR), synthetic polyisoprene (IR), butyl rubber (IIR), halogenated butyl rubber (XIIR), acrylate rubber (ACM), ethylene-vinyl acetate copolymer (EVA), and polyurethane and / or blends thereof.

[0098] Also preferably, the adhesive coating consists of: a synthetic rubber-based adhesive, more particularly an adhesive composed of at least one vinyl aromatic block copolymer and at least one tackifier resin. Typical concentrations of the block copolymer used are in the range of 30% to 70% by weight, more particularly in the range of 35% to 55% by weight.

[0099] Other polymers that may exist are those based on pure hydrocarbons, such as unsaturated polydienes like naturally or synthetically produced polyisoprene or polybutadiene; those based on chemically substantially saturated elastomers, such as saturated ethylene-propylene copolymers, α-olefin copolymers, polyisobutylene, butyl rubber, ethylene-propylene rubber; and those based on chemically functionalized hydrocarbons, such as polyolefins containing halogens, acrylates, or vinyl ethers, which may replace up to half of the block copolymers containing vinyl aromatic compounds.

[0100] The tackifier is a tackifier resin that is compatible with the elastomeric blocks of the styrene block copolymer.

[0101] Typically, plasticizers such as liquid resins, plasticizer oils, or low molecular weight liquid polymers, such as low molecular weight polyisobutylene with a molar mass <1500 g / mol (number average), or liquid EPDM products are used.

[0102] Other additives that may be added to all types of adhesives include light stabilizers such as UV absorbers, steric amines, ozone inhibitors, metal passivators, processing aids, and end-block reinforcing resins.

[0103] Fillers such as silica, glass (ground or in bead form, as solid or hollow beads), microspheres, alumina, zinc oxide, calcium carbonate, titanium dioxide, carbon black, silicates and chalk, to name just a few, as well as pigments and dyes, and optical brighteners can also be used.

[0104] Typically, PSA is mixed with primary and secondary antioxidants to improve its aging stability. The primary antioxidant reacts with oxygen and peroxide groups (free radicals) that can be formed in the presence of oxygen, and reacts with them to form less reactive compounds. For example, the secondary antioxidant reduces hydroperoxides to alcohols. A synergistic effect between the primary and secondary aging inhibitors is known, and therefore the protective effect of the mixture is often greater than the sum of the effects of the two individual inhibitors.

[0105] More preferably, the rubber can be added to the thermoplastic elastomer at a weight fraction of 10 to 50% (based on the total elastomer fraction) to improve processability.

[0106] Representatives mentioned herein include, in particular, particularly compatible styrene-isoprene-styrene (SIS) and styrene-butadiene-styrene (SBS) products. Suitable elastomers for blending also include, for example, EPDM or EPM rubber, polyisobutylene, butyl rubber, ethylene-vinyl acetate, hydrogenated block copolymers made from dienes (e.g., by hydrogenation of SBR, cSBR, BAN, NBR, SBS, SIS, or IR; such polymers are known, for example, in the form of SEPS and SEBS), or acrylate copolymers such as ACM.

[0107] In addition, a 100% system based on styrene-isoprene-styrene (SIS) has been found to be suitable.

[0108] Crosslinking is beneficial for improving the removability of tape after use and can be accomplished by heat or by using UV light or electron beam irradiation.

[0109] For the purpose of thermally induced chemical crosslinking, all known thermally activatable chemical crosslinking agents may be used, such as accelerated sulfur or sulfur donor systems, isocyanate systems, reactive melamine, formaldehyde and (optionally halogenated) phenolic (phenol-formaldehyde) resins and / or reactive phenolic resins or diisocyanate crosslinking systems with corresponding activators, epoxidized polyester resins and acrylate resins, and combinations thereof.

[0110] The crosslinking agent is preferably activated at a temperature above 50°C, more particularly at a temperature of 100°C-160°C, and very preferably at a temperature of 110°C-140°C.

[0111] Thermal excitation of the crosslinking agent can also be achieved through IR rays or a high-energy alternating field.

[0112] Solvent-based or water-based adhesives, or adhesives in the form of hot melt systems, can be used. Acrylic hot melt-based substances are also suitable, wherein the substance may have a K value of at least 20, more particularly greater than 30, which can be obtained by concentrating a solution of such a substance to form a system that can be processed as a hot melt.

[0113] Concentration can be carried out in a suitably equipped tank or extruder; in particular, a degassed extruder is preferred when degassing is involved.

[0114] One type of adhesive is described in DE 43 13 008 A1, the contents of which are incorporated herein by reference and form part of this disclosure and invention.

[0115] However, adhesives based on acrylate hot melts can also be chemically cross-linked.

[0116] The K value is specifically determined here in accordance with DIN 53 726.

[0117] Additionally, other volatile components are removed during this process. After being coated from the melt, these compositions retain only a small fraction of the volatile components. Therefore, all the monomers / formulations claimed in the patents mentioned above can be used.

[0118] The solution of this substance may have a solvent content of 5-80% by weight, more particularly 30-70% by weight.

[0119] Commercial solvents are preferred, especially low-boiling hydrocarbons, ketones, alcohols and / or esters.

[0120] Further preferred is the use of a single-screw, twin-screw, or multi-screw extruder having one or, particularly, two or more degassing units.

[0121] Adhesives based on acrylate hot melts may have benzoin derivatives copolymerized therein, such as benzoin acrylate or benzoin methacrylate, acrylate or methacrylate. Such benzoin derivatives are described in EP0 578 151 A.

[0122] Adhesives based on acrylate hot melts can be UV crosslinked. However, other crosslinking methods are also possible, such as electron beam crosslinking.

[0123] In another preferred embodiment, the self-adhesive material used is a copolymer of (meth)acrylic acid and its esters having 1 to 25 carbon atoms, maleic acid, fumaric acid and / or itaconic acid and / or their esters, substituted (meth)acrylamide, maleic anhydride and other vinyl compounds such as vinyl esters, particularly vinyl acetate, vinyl alcohols and / or vinyl ethers.

[0124] Similarly suitable adhesives are low molecular weight acrylic hot-melt pressure-sensitive adhesives, such as those produced by BASF under the name acResin UV or... More specifically Promoted by DS 3458 or AC Resin A260UV. This low-K value adhesive achieves its application-matching properties by means of final crosslinking initiated by radiation chemistry.

[0125] Other very suitable adhesives are described in EP 2 520 627 A1, EP 2 522 705 A1, EP 2 520 628 A1, EP 2 695 926 A1 and EP 2 520 629 A1.

[0126] Particularly preferred is the dry polymer dispersion form of PSA, wherein the polymer comprises the following:

[0127] (a) 95.0-100.0% by weight of n-butyl acrylate and / or 2-ethylhexyl acrylate

[0128] (b) 0.0-5.0% by weight of olefinic unsaturated monomers having acid or anhydride functional groups.

[0129] The polymer preferably comprises: 95.0-99.5% by weight of n-butyl acrylate and / or 2-ethylhexyl acrylate and 0.5-5% by weight of an olefinic unsaturated monomer having acid or anhydride functional groups; more preferably, 97.0 or 98.0%-99.0% by weight of n-butyl acrylate and / or 2-ethylhexyl acrylate and 1.0-2.0% or 3% by weight of an olefinic unsaturated monomer having acid or anhydride functional groups.

[0130] In addition to the acrylate polymers described above, PSA may also be mixed with tackifiers and / or auxiliaries such as light stabilizers or aging inhibitors, except for any residual monomers present.

[0131] In particular, no other polymers such as elastomers exist in PSA, which means that the polymer of PSA consists only of monomers (a) and (b) in specified proportions.

[0132] The monomer (a) is preferably formed from n-butyl acrylate.

[0133] Examples of monomers to be considered as (b) advantageously include acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid and / or maleic anhydride.

[0134] Preferred is (meth)acrylic acid of formula I.

[0135]

[0136] Where R 3 =H or CH3; optionally, a mixture of acrylic acid or methacrylic acid is preferred. Acrylic acid is particularly preferred.

[0137] According to a particularly preferred variant, the polymer composition is as follows:

[0138] (a) 95.0-100.0% by weight, preferably 95.0-99.5% by weight, more preferably 98.0-99.0% by weight of n-butyl acrylate, and

[0139] (b) 0.0-5.0% by weight, preferably 0.5-5.0% by weight, more preferably 1.0-2.0% by weight of acrylic acid.

[0140] The polymer dispersion was prepared by emulsion polymerization of the components described herein. A description of this method can be found, for example, in Peter A. Lovell and Mohamed S. El-Aasser's "Emulsion Polymerization and Emulsion Polymers" - Wiley-VCH 1997 - ISBN 0-471-96746-7 or EP 1 378 527 B1.

[0141] During polymerization, it is impossible for all monomers to undergo the reaction to form a polymer. Therefore, it is clear that the residual monomer content should be as low as possible.

[0142] It is preferred to provide adhesives comprising a polymer dispersion having a residual monomer content (based on the mass of the dried polymer dispersion) of less than or equal to 1% by weight, more particularly less than or equal to 0.5% by weight.

[0143] Finally, it is also appropriate to mention polyurethane-based adhesives.

[0144] To optimize properties, the self-adhesive material can be blended with one or more additives such as tackifiers (resins), plasticizers, fillers, pigments, UV absorbers, light stabilizers, aging inhibitors, crosslinking agents, crosslinking promoters, or elastomers.

[0145] The tackifiers used are those resins that have already been fully described.

[0146] Examples of suitable fillers and pigments include carbon black, titanium dioxide, calcium carbonate, zinc carbonate, zinc oxide, silicates, or silicon dioxide.

[0147] Suitable plasticizers include, for example, aliphatic, alicyclic and aromatic mineral oils, diesters or polyesters of phthalic acid, trimellitic acid or adipic acid, liquid rubbers (e.g., nitrile rubber or polyisoprene rubber), liquid polymers of butene and / or isobutylene, acrylates, polyvinyl ethers, plasticizing resins and liquid resins based on raw materials used for tackifier resins, lanolin wax and other waxes, or liquid silicones.

[0148] Crosslinking agents are, for example, phenolic resins or halogenated phenolic resins, melamine, and formaldehyde resins. Suitable crosslinking accelerators are, for example, maleimide, allyl esters such as triallyl cyanurate, and polyfunctional esters of acrylic acid and methacrylic acid.

[0149] According to the general understanding of technicians, "tackifier resin" is an oligomer or polymer resin that improves the self-adhesion (tackiness, inherent adhesion) of PSA compared to PSA that is otherwise identical without tackifier resin.

[0150] The use of tackifiers to improve the peel adhesion value of PSA is generally known. This effect is also achieved by mixing the adhesive with up to 15 parts by weight (corresponding to <15 parts by weight), or 5-15 parts by weight (based on the mass of the dry polymer dispersion). Preferably, 5-12, more preferably 6-10 parts by weight (based on the mass of the dry polymer dispersion) of tackifier are added.

[0151] Suitable tackifiers (also known as tackifier resins) are, in principle, 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- 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 glycols, 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 more preferably resins prepared by hydrogenation, such as hydrogenated aromatic resins, hydrogenated polycyclopentadiene resins, hydrogenated rosin derivatives, or hydrogenated polyterpene resins.

[0152] Preferred resins are those based on terpene phenols and rosin esters. Also preferred are tackifying resins having a softening point exceeding 80°C according to ASTM E28-99 (2009). Particularly preferred resins are those based on terpene phenols and rosin esters having a softening point exceeding 90°C according to ASTM E28-99 (2009). These resins are advantageously used in dispersion form. In this form, they can readily withstand fine mixing with polymer dispersions.

[0153] In particularly preferred variants, no tackifier resin is added to the PSA at all.

[0154] The following substances are specifically not added to PSA:

[0155] • Hydrocarbon resins (e.g., polymers based on unsaturated C5 or C9 monomers)

[0156] · Terpene-phenolic resin

[0157] Polyterpene resins based on raw materials such as α- or β-pinene

[0158] • 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, examples of which are reaction products with glycols, glycerol or pentaerythritol.

[0159] "Poly(meth)acrylate" is a polymer whose monomer base comprises at least 60% by weight acrylic acid, methacrylic acid, acrylates and / or methacrylates, wherein it comprises at least proportionally, preferably not less than 50% by weight, acrylates and / or methacrylates, based on the total monomer base of the polymer under discussion. More particularly, "poly(meth)acrylate" is a polymer obtainable by free radical polymerization of acrylic and / or methacrylic monomers and optionally other copolymerizable monomers.

[0160] In this invention, poly(meth)acrylate is present in 30 to 65% by weight, based on the total weight of the PSA. The PSA of this invention preferably comprises 35 to 55% by weight of at least one poly(meth)acrylate, based on the total weight of the PSA.

[0161] The glass transition temperature of the poly(meth)acrylates that can be used in this invention is preferably <0°C, more preferably between -20°C and -50°C.

[0162] For the purposes of this invention, the glass transition temperature of the polymer or polymer block in the block copolymer is determined by dynamic scanning calorimetry (DSC).

[0163] The poly(meth)acrylate of the PSA of the present invention is preferably obtained by copolymerization of functional monomers at least in proportion, said functional monomers preferably being crosslinkable to epoxy groups. These monomers are more preferably those having acid groups (particularly carboxylic acid, sulfonic acid, or phosphonic acid groups) and / or hydroxyl and / or anhydride and / or epoxy and / or amine groups; monomers containing carboxylic acid groups are particularly preferred. It is particularly advantageous that the polyacrylate comprises copolymerized acrylic acid and / or methacrylic acid. All these groups are characterized by crosslinkability to epoxy groups, thus making the polyacrylate advantageously suitable for thermal crosslinking with the introduced epoxide.

[0164] In addition to acrylates and / or methacrylates having up to 30 carbon atoms per molecule, other monomers that can be used as comonomers of poly(meth)acrylates are, for example, vinyl esters of carboxylic acids having up to 20 carbon atoms, vinyl aromatic compounds having up to 20 carbon atoms, olefinic unsaturated nitriles, vinyl halides, vinyl ethers of alcohols having 1 to 10 carbon atoms, aliphatic hydrocarbons having 2 to 8 carbon atoms and one or two double bonds, or mixtures of these monomers.

[0165] The properties of the poly(meth)acrylates discussed can be particularly affected by the variation in the glass transition temperature of the polymer due to different weight fractions of the monomers. The poly(meth)acrylates of the present invention are preferably derived from the following monomer compositions:

[0166] a) Acrylates and / or methacrylates of the following formula:

[0167] CH2=C(R I (COOR) II )

[0168] Where R I =H or CH3 and R II It is an alkyl group having 4-14 carbon atoms.

[0169] b) Alkenyl unsaturated monomers having functional groups of a defined type that are reactive with epoxy groups.

[0170] c) Additional acrylates and / or methacrylates and / or olefinic unsaturated monomers that may optionally copolymerize with component (a).

[0171] Preferably, the fractions of the respective components (a), (b), and (c) are selected such that the polymeric product has a glass transition temperature (DSC) <0°C, more preferably between -20°C and -50°C. Particularly advantageous are monomers of component (a) having a fraction of 45 to 99 wt%, monomers of component (b) having a fraction of 1 to 15 wt%, and monomers of component (c) having a fraction of 0 to 40 wt% (these figures are based on a mixture of monomers for the “base polymer” (in other words, without any additives, such as resins, etc., added to the finished polymer).

[0172] The monomer of component (a) is more particularly a plasticizing and / or nonpolar monomer. Preferred monomers for use as monomer (a) are acrylates and methacrylates having an alkyl group consisting of 4 to 14 carbon atoms, more preferably 4 to 9 carbon atoms. Examples of such monomers are n-butyl acrylate, n-butyl methacrylate, n-pentyl acrylate, n-pentyl methacrylate, n-pentyl acrylate, n-hexyl acrylate, n-hexyl methacrylate, n-heptyl acrylate, n-octyl acrylate, n-octyl methacrylate, n-nonyl acrylate, and their branched isomers, such as isobutyl acrylate, isooctyl acrylate, isooctyl methacrylate, 2-ethylhexyl acrylate, or 2-ethylhexyl methacrylate.

[0173] The monomer of component (b) is more particularly an olefinic unsaturated monomer having a functional group, particularly having a functional group capable of reacting with an epoxy group.

[0174] Preferably, the monomer used in component (b) is a monomer having a functional group selected from the following: hydroxyl, carboxyl, sulfonic acid or phosphonic acid, acid anhydride, epoxide, amine.

[0175] Particularly preferred examples of monomers for component (b) are acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, aconitic acid, dimethacrylic acid, β-acryloyloxypropionic acid, trichloroacrylic acid, vinylacetic acid, vinylphosphonic acid, maleic anhydride, hydroxyethyl acrylate, particularly 2-hydroxyethyl acrylate, hydroxypropyl acrylate, particularly 3-hydroxypropyl acrylate, hydroxybutyl acrylate, particularly 4-hydroxybutyl acrylate, hydroxyhexyl acrylate, particularly 6-hydroxyhexyl acrylate, hydroxyethyl methacrylate, particularly 2-hydroxyethyl methacrylate, hydroxypropyl methacrylate, particularly 3-hydroxypropyl methacrylate, hydroxybutyl methacrylate, particularly 4-hydroxybutyl methacrylate, hydroxyhexyl methacrylate, particularly 6-hydroxyhexyl methacrylate, allyl alcohol, glycidyl acrylate, and glycidyl methacrylate.

[0176] In principle, any vinyl-functionalized compound that can be copolymerized with component (a) and / or component (b) can be used as component (c). Monomers of component (c) can be used to adjust the properties of the resulting PSA.

[0177] The following are exemplary monomers of component (c):

[0178] Methyl acrylate, ethyl acrylate, propyl acrylate, methyl methacrylate, ethyl methacrylate, benzyl acrylate, benzyl methacrylate, sec-butyl acrylate, tert-butyl acrylate, phenyl acrylate, phenyl methacrylate, isobornyl acrylate, isobornyl methacrylate, tert-butylphenyl acrylate, tert-butylphenyl methacrylate, dodecyl methacrylate, isodecyl acrylate, lauryl acrylate, n-undecyl acrylate, stearyl acrylate, tridecyl acrylate, dodecyl acrylate, cyclohexyl methacrylate, cyclopentyl methacrylate, phenoxyethyl acrylate, phenoxyethyl methacrylate, 2-butoxy methacrylate 2-Butoxyethyl acrylate, 3,3,5-Trimethylcyclohexyl acrylate, 3,5-Dimethyladamantyl acrylate, 4-Cuylphenyl methacrylate, Ethyl cyanoacrylate, Ethyl cyanomethacrylate, 4-Biphenyl acrylate, 4-Biphenyl methacrylate, 2-Naphthyl acrylate, 2-Naphthyl methacrylate, Tetrahydrofurfuryl acrylate, Diethylaminoethyl acrylate, Diethylaminoethyl methacrylate, Dimethylaminoethyl acrylate, Dimethylaminoethyl methacrylate, 2-Butoxyethyl acrylate, 2-Butoxyethyl methacrylate, Methyl 3-Methoxyacrylate, 3-Methoxybutyl acrylate, Phenoxyethyl acrylate, Methyl Phenoxyethyl acrylate, 2-phenoxyethyl methacrylate, butyl diethylene glycol methacrylate, ethylene glycol acrylate, ethylene glycol monomethyl ether acrylate, methoxy polyethylene glycol methacrylate 350, methoxy polyethylene glycol methacrylate 500, propylene glycol monomethyl methacrylate, butoxydiethylene glycol methacrylate, ethoxytriethylene glycol methacrylate, octafluoropentyl acrylate, octafluoropentyl methacrylate, 2,2,2-trifluoroethyl methacrylate, 1,1,1,3,3,3-hexafluoroisopropyl acrylate, 1,1,1,3,3,3-hexafluoroisopropyl methacrylate, 2,2,3,3,3-pentafluoropropyl methacrylate, 2,2 3,4,4,4-Hexafluorobutyl acrylate, 2,2,3,3,4,4,4-Hepenobutyl acrylate, 2,2,3,3,4,4,4-Hepenobutyl methacrylate, 2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-Pentadecylfluorooctyl acrylate, Dimethylaminopropylacrylamide, Dimethylaminopropylmethacrylamide, N-(1-Methylundecyl)acrylamide, N-(n-Butoxymethyl)acrylamide, N-(Butoxymethyl)methacrylamide, N-(Ethoxymethyl)acrylamide, N-(n-Octadecyl)acrylamide, and N,N-dialkyl-substituted amides such as N,N-dimethylacrylamide, N,N-Dimethylmethacrylamide, N-Benzylacrylamide, N-Isopropylacrylamide, N-T-Butylacrylamide, N-T-Octylacrylamide, N-Hydroxymethylacrylamide, N-Hydroxymethylmethacrylamide, Acrylonitrile, Methacrylonitrile, Vinyl ethers such as vinyl methyl ether, ethyl vinyl ether, vinyl isobutyl ether, Vinyl esters such as vinyl acetate, Vinyl chloride, Vinyl halides, Vinylidene chloride, Vinylidene halide, Vinylpyridine, 4-Vinylpyridine, N-Vinylphthalimide, N-Vinyl lactam, N-Vinylpyrrolidone, Styrene, α-Methylstyrene and p-Methylstyrene, α-Butylstyrene, 4-n-Butylstyrene, 4-n-Decylstyrene, 3,4-Dimethoxystyrene, Macromonomers such as 2-Polystyrene-ethyl methacrylate (weight average molecular weight M of 4000-13000 g / mol), w (Measured by GPC), poly(methyl methacrylate)-ethyl methacrylate (2000-8000 g / mol M w ).

[0179] The monomers of component (c) may also be advantageously selected such that they include functional groups that support subsequent radiation-chemical crosslinking (e.g., by electron beam or UV). Suitable copolymerizable photoinitiators are, for example, benzoin acrylate and acrylate-functionalized benzophenone derivatives. Monomers that support crosslinking by electron bombardment are, for example, tetrahydrofurfuryl acrylate, N-tert-butylacrylamide, and allyl acrylate.

[0180] Polyacrylates (“polyacrylate” is understood in the context of this invention to be synonymous with “poly(meth)acrylate”) can be prepared by methods familiar to those skilled in the art, particularly advantageously by conventional free radical polymerization or controlled free radical polymerization. Polyacrylates can be prepared by copolymerizing monomer components using conventional polymerization initiators and optionally chain transfer agents, with polymerization carried out at conventional temperatures in bulk, in emulsions such as in water or liquid hydrocarbons, or in solution.

[0181] Polyacrylates are preferably prepared by polymerizing the monomers in a solvent, more particularly in a solvent having a boiling range of 50-150°C, preferably 60-120°C, using a conventional amount (typically 0.01 to 5, more particularly 0.1 to 2 wt%, based on the total weight of the monomers) of a polymerization initiator.

[0182] In principle, all conventional initiators familiar to the technician are suitable. Examples of free radical sources are peroxides, hydroperoxides, and azo compounds, such as benzoyl peroxide, cumene hydroperoxide, cyclohexanone peroxide, di-tert-butyl peroxide, cyclohexylsulfonylacetyl peroxide, diisopropyl percarbonate, tert-butyl peroctanoate, and benzylpinacol. A highly preferred procedure uses 2,2'-azobis(2-methylbutyronitrile) (from DuPont). 67 TM ) or 2,2'-azobis(2-methylpropionitrile) (2,2'-azobisisobutyronitrile; AIBN; from DuPont) 64 TM It acts as a free radical initiator.

[0183] Suitable solvents for the preparation of poly(meth)acrylates include alcohols such as methanol, ethanol, n-propanol and isopropanol, n-butanol and isobutanol, preferably isopropanol and / or isobutanol, and hydrocarbons such as toluene, and more particularly mineral oils (solvent oils) having a boiling range of 60 to 120°C. Other possibilities include ketones such as preferably acetone, methyl ethyl ketone and methyl isobutyl ketone, and esters such as ethyl acetate, and mixtures of solvents of these types, preferably mixtures including isopropanol, particularly in amounts of 2 to 15% by weight, preferably 3 to 10% by weight, based on the solvent mixture used.

[0184] Preferably, the preparation (polymerization) of the polyacrylate is followed by a concentration process, and further processing of the polyacrylate is carried out in the absence of substantially any solvent. The concentration of the polymer can be carried out in the absence of crosslinking agents and accelerators. However, it is also possible to add one of these types of compounds to the polymer even before concentration, so that concentration is carried out in the presence of that substance.

[0185] Weight-average molecular weight M of polyacrylate w Preferably, the molecular weight is in the range of 20,000-2,000,000 g / mol; most preferably, it is in the range of 100,000-1,500,000 g / mol; and most preferably, it is in the range of 150,000-1,000,000 g / mol. The average molecular weight M in this document... w The numerical values ​​for polydispersity PD involve determination by gel permeation chromatography. For this purpose, it is advantageous to polymerize in the presence of a suitable chain transfer agent such as a thiol, halogen compound, and / or alcohol to set the desired average molecular weight.

[0186] The polyacrylate preferably has a K value of 30 to 90, more preferably 40 to 70, measured in toluene (1% concentration solution, 21°C). According to Fickentscher, the K value is a measure of the polymer's molecular weight and viscosity.

[0187] Polyacrylates with a narrow molecular weight distribution (polydispersity PD < 4) are particularly suitable according to the invention. Despite their relatively low molecular weight after crosslinking, these materials exhibit particularly good shear strength. The relatively low polydispersity also facilitates processing from the melt, as the flow viscosity is lower than that of polyacrylates with a wider range of applications while maintaining substantially the same properties. Narrow-range poly(meth)acrylates can advantageously be prepared by anionic polymerization or by controlled radical polymerization, the latter being particularly suitable. Such polyacrylates can also be prepared via N-oxygen groups. Furthermore, atom transfer radical polymerization (ATRP) is advantageously used to synthesize narrow-range polyacrylates, with the initiator preferably comprising monofunctional or bifunctional secondary or tertiary halides, said halides being extracted using complexes of Cu, Ni, Fe, Pd, Pt, Ru, Os, Rh, Co, Ir, Ag, or Au.

[0188] Preferably, the monomers used to prepare poly(meth)acrylates include, in proportion, functional groups suitable for linkage reactions with epoxy groups. This advantageously allows the polyacrylate to undergo thermal crosslinking via reaction with epoxides. In particular, linkage reactions are understood as addition and substitution reactions. Therefore, preferably, functional group-carrying building units (structural blocks) are linked to epoxy group-carrying building units, more particularly in the sense that the functional group-carrying polymer building units are crosslinked via linking bridges comprising crosslinking agent molecules carrying epoxy groups. Substances containing epoxy groups are preferably polyfunctional epoxides, in other words, those having at least two epoxy groups; therefore, preferably, the overall result is an indirect linkage of functional group-carrying building units.

[0189] The poly(meth)acrylates of the PSA of the present invention are preferably crosslinked via a linkage reaction (particularly in the sense of addition or substitution) between their contained functional groups and a thermal crosslinking agent. All thermal crosslinking agents that not only ensure a sufficiently long processing life (meaning no gelling during processing operations, particularly extrusion operations), but also cause the polymer to rapidly post-crosslink to the desired degree of crosslinking at temperatures below the processing temperature, more particularly at room temperature. For example, combinations of carboxyl-containing, amino-containing, and / or hydroxyl-containing polymers with isocyanates, more particularly aliphatic isocyanates, or triisocyanates deactivated with amines as crosslinking agents are possible.

[0190] More specifically, suitable isocyanates are trimer derivatives such as MDI [4,4'-methylene di(phenyl isocyanate)], HDI [hexamethylene diisocyanate, 1,6-hexanediisocyanate] and / or IPDI [isophorone diisocyanate, 5-isocyano-1-isocyanomethyl-1,3,3-trimethylcyclohexane], examples of which are of type [type]. N3600 and XP2410 (each BAYER AG: aliphatic polyisocyanate, low viscosity HDI trimer). Also suitable is the micronized trimer of surface-deactivated IPDI dispersion BUEJ. (now is) (BAYER AG).

[0191] However, other isocyanates are also suitable for crosslinking in principle, such as Desmodur VL 50 (MDI-based polyisocyanate, Bayer AG), Basonat F200WD (aliphatic polyisocyanate, BASF AG), Basonat HW100 (water-emulsifiable multifunctional HDI-based isocyanate, BASF AG), Basonat HA300 (urethane-modified polyisocyanate based on HDI isocyanurate, BASF), or Bayhydur VPLS2150 / 1 (hydrophilically modified IPDI, Bayer AG).

[0192] The thermal crosslinking agent is preferably used at 0.1 to 5% by weight, more particularly at 0.2 to 1% by weight, based on the total amount of the polymer to be crosslinked.

[0193] The poly(meth)acrylate of PSA is preferably crosslinked via one or more epoxides or one or more substances containing epoxy groups. Substances containing epoxy groups are more particularly polyfunctional epoxides, in other words, those having at least two epoxy groups; thus, the overall result is an indirect connection of the building units of the poly(meth)acrylate carrying functional groups. Substances containing epoxy groups can be aromatic compounds and can be aliphatic compounds.

[0194] Ideally suited for use with oligomers of polyfunctional epoxides such as epichlorohydrins, polyhydroxy alcohols (more particularly ethylene glycol, propylene glycol and butylene glycol, polyethylene glycol, thiodiglycol, glycerol, pentaerythritol, sorbitol, polyvinyl alcohol, polyallyl alcohol, etc.), epoxy ethers of polyhydroxyphenols (more particularly resorcinol, hydroquinone, bis(4-hydroxyphenyl)methane, bis(4-hydroxy-3-methylphenyl)methane, bis(4-hydroxy-3,5-dibromophenyl)methane, bis(4-hydroxy-3,5-dibromophenyl)methane, bis(4-hydroxy-3,5-dibromophenyl)methane, etc.). 1,1-bis(4-hydroxyphenyl)methane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxy-3-methylphenyl)propane, 2,2-bis(4-hydroxy-3-chlorophenyl)propane, 2,2-bis(4-hydroxy-3,5-dichlorophenyl)propane, bis(4-hydroxyphenyl)phenylmethane, bis(4-hydroxyphenyl)diphenylmethane, bis(4-hydroxyphenyl)-4'-methylphenylmethane, 1,1-bis(4-hydroxyphenyl)methane Epoxy ethers of 1,1-bis(4-hydroxyphenyl)cyclohexane, bis(4-hydroxyphenyl)(4-chlorophenyl)methane, 1,1-bis(4-hydroxyphenyl)cyclohexane, bis(4-hydroxyphenyl)cyclohexylmethane, 4,4'-dihydroxybiphenyl, 2,2'-dihydroxybiphenyl, 4,4'-dihydroxydiphenyl sulfone, and their hydroxyethyl ethers; phenol-formaldehyde condensation products such as phenolic alcohols, phenolic resins, etc.; S-containing epoxides and N-containing epoxides (e.g., N, N-diglycidyl aniline, N,N'-dimethyldiglycidyl-4,4-diaminodiphenylmethane), and epoxides, glycidyl esters, and polyglycidyl esters prepared by conventional methods from monounsaturated or polyunsaturated carboxylic acid esters of unsaturated alcohols, which may be obtained by polymerization or copolymerization of glycidyl esters of unsaturated acids or by other acidic compounds (cyanuric acid, diglycidyl sulfides, cyclic trimethylene trisulfone and / or its derivatives, and others).

[0195] Very suitable ethers include, for example, 1,4-butanediol diglycidyl ether, polyglycerol-3-glycidyl ether, cyclohexanediethanol diglycidyl ether, glycerol triglycidyl ether, neopentyl glycol diglycidyl ether, pentaerythritol tetraglycidyl ether, 1,6-hexanediol diglycidyl ether, polypropylene glycol diglycidyl ether, trimethylolpropane triglycidyl ether, bisphenol A diglycidyl ether, and bisphenol F diglycidyl ether.

[0196] For poly(meth)acrylates as the polymer to be crosslinked, it is particularly preferred to use a crosslinking agent-accelerator system (“crosslinking system”) (e.g., described in EP 1 978 069 A1) to obtain more effective control over processing life, crosslinking kinetics, and the degree of crosslinking. This crosslinking agent-accelerator system comprises at least one epoxy-containing substance as a crosslinking agent and at least one substance as an accelerator that has a promoting effect on the crosslinking reaction of the epoxy-functionalized compound at a temperature below the melting temperature of the polymer to be crosslinked.

[0197] The accelerators used according to the invention are more preferably amines (formally interpreted as substituted products of ammonia; in the following formula, these substituents are represented by "R" and particularly include alkyl and / or aryl groups and / or other organic groups), and more particularly preferably those amines that do not react or only slightly react with the building units of the polymer to be crosslinked.

[0198] In principle, primary amines (NRH2), secondary amines (NR2H), and tertiary amines (NR3) can be selected as accelerators, as well as those having two or more primary and / or secondary and / or tertiary amine groups. However, particularly preferred accelerators are tertiary amines, such as triethylamine, triethylenediamine, benzyldimethylamine, dimethylaminomethylphenol, 2,4,6-tris(N,N-dimethylaminomethyl)phenol, and N,N'-bis(3-(dimethylamino)propyl)urea. Polyfunctional amines such as diamines, triamines, and / or tetraamines can also be advantageously used as accelerators. For example, diethylenetriamine, triethylenetetramine, and trimethylhexamethylenediamine are very suitable.

[0199] Furthermore, amino alcohols are preferably used as promoters. Secondary and / or tertiary amino alcohols are particularly preferred, wherein, in the case of two or more amine functional groups (functionality) per molecule, at least one of the amine functional groups is preferably secondary and / or tertiary. As preferred amino alcohol promoters, triethanolamine, N,N-bis(2-hydroxypropyl)ethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, 2-aminocyclohexanol, bis(2-hydroxycyclohexyl)methylamine, 2-(diisopropylamino)ethanol, 2-(dibutylamino)ethanol, N-butyldiethanolamine, N-butylethanolamine, 2-[bis(2-hydroxyethyl)amino]-2-(hydroxymethyl)-1,3-propanediol, 1-[bis(2-hydroxyethyl)amino]-2-propanol, triisopropanolamine, 2-(dimethylamino)ethanol, 2-(diethylamino)ethanol, 2-(2-dimethylaminoethoxy)ethanol, N,N,N'-trimethyl-N'-hydroxyethylbisaminoethyl ether, N,N,N'-trimethylaminoethylethanolamine and / or N,N,N'-trimethylaminopropyl-ethanolamine.

[0200] Other suitable accelerators are pyridine, imidazoles (e.g., 2-methylimidazolium), and 1,8-diazabicyclo[5.4.0]undec-7-ene. Alicyclic polyamines can also be used as accelerators. Suitable accelerators are also phosphorus-based, such as phosphine and / or... Compounds, such as triphenylphosphine or tetraphenylphosphine Tetraphenylborate.

[0201] Acrylate PSAs are typically copolymers of free radical polymers of the following: alkyl acrylates or alkyl methacrylates of C1 to C20 alcohols, such as methyl acrylate, ethyl acrylate, n-butyl acrylate, tert-butyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, isooctyl acrylate, n-decyl acrylate, n-dodecyl acrylate, tetradecyl acrylate, lauryl acrylate, oleyl acrylate, palmityl acrylate, and stearyl acrylate, as well as other methacrylates such as isobornyl acrylate, benzyl acrylate, phenyl acrylate, and 2-bromoethyl acrylate, and alkoxyalkyl acrylates such as ethoxyethyl acrylate. This also includes esters of olefinic unsaturated dicarboxylic acids and tricarboxylic acids and anhydrides, such as ethyl maleate, dimethyl fumarate, and ethyl methyl itaconic acid. Also included are vinyl aromatic monomers such as styrene, vinyltoluene, methylstyrene, n-butylstyrene, and decylstyrene.

[0202] Other possible monomers include vinyl esters of carboxylic acids with up to 20 carbon atoms, such as vinyl acetate or vinyl laurate; vinyl ethers of alcohols with up to 10 carbon atoms, such as vinyl methyl ether or vinyl isobutyl ether; vinyl halides, such as vinyl chloride or vinylidene chloride; nitriles, such as acrylonitrile or methacrylonitrile; amides, such as acrylamide or methacrylamide; and unsaturated hydrocarbons having 2-8 carbon atoms, such as ethylene, propylene, butadiene, isoprene, 1-hexene, or 1-octene.

[0203] Multifunctional olefinic unsaturated monomers are considered as crosslinking monomers for purposes influencing the physical and optical properties of PSA. Examples in this regard are divinylbenzene, alkyl diacrylates such as 1,2-ethylene glycol diacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,8-octanediol diacrylate, or 1,12-dodecanediol diacrylate, triacrylates such as trimethylolpropane triacrylate, and tetraacrylates such as pentaerythritol tetraacrylate. The group of multifunctional monomers also includes UV-crosslinkable monomers, such as (meth)acrylate-functionalized derivatives of benzophenone or benzoin.

[0204] Another group of monomers belongs to those that possess the potential to create crosslinks within the polymer and spontaneously (often with the use of a catalyst) lead to the formation of a network after the adhesive dries. An example of such a monomer is glycidyl methacrylate, whose ethylene oxide ring leads to ring-opening with a hydroxyl functional group, or particularly with a carboxylic acid ester functional group, and thus to covalent bonding. The reaction proceeds in an accelerated manner in the presence of zinc ions or (particularly when a carboxyl functional group is present) amines.

[0205] To obtain the properties of pressure-sensitive adhesives, the processing temperature of the adhesive must be higher than its glass transition temperature to achieve viscoelastic properties.

[0206] Furthermore, the acrylate-based reactivatable adhesive of the present invention can be used. In this case, in a particularly preferred form, the reactivatable adhesive is composed of the following:

[0207] The basic polymer a) is composed of the following:

[0208] a1) 40 to 95% by weight of acrylates and / or methacrylates having the following formula

[0209] CH2=C(R1)(COOR2)

[0210] Where R1 = H or CH3 and R2 = alkyl chain with 1 to 30 carbon atoms.

[0211] a2) 5 to 30% by weight of copolymerizable vinyl monomers having at least one carboxylic acid and / or sulfonic acid and / or phosphonic acid group.

[0212] a3) 1 to 10% by weight of copolymerizable vinyl monomers having at least one epoxy group or one anhydride functional group.

[0213] a4) 0 to 20% by weight of copolymerizable vinyl monomers having functional groups that contribute to enhanced cohesiveness, increased crosslinking reactivity, or direct crosslinking, and

[0214] b) 5 to 50% by weight of epoxy resin or a mixture of two or more epoxy resins.

[0215] Polymer a) may include an activatable PSA that becomes pressure-sensitive adhesive upon exposure to temperature and optionally pressure, and develops high adhesive strength through curing after bonding and cooling. Depending on the application temperature, these activatable PSAs have different static glass transition temperatures T0. g,A or melting point T m,A .

[0216] In a highly preferred form, the monomer used for monomer a1) is an acrylic monomer, comprising acrylates and methacrylates having alkyl groups comprising 4 to 14 carbon atoms, preferably 4 to 9 carbon atoms. Specific examples (not intended to impose any limitation) are n-butyl acrylate, n-pentyl acrylate, n-hexyl acrylate, n-heptyl acrylate, n-octyl acrylate, n-nonyl acrylate, lauryl acrylate, stearyl acrylate, docosyl acrylate, and their branched isomers such as 2-ethylhexyl acrylate. Other classes of compounds that may also be used in small amounts under a1) are methyl methacrylate, cyclohexyl methacrylate, isobornyl acrylate, and isobornyl methacrylate.

[0217] Preferred monomers (a2) include itaconic acid, acrylic acid, methacrylic acid, vinylacetic acid, fumaric acid, crotonic acid, aconitic acid, dimethacrylic acid, β-acryloyloxypropionic acid, trichloroacrylic acid, vinylphosphonic acid, and vinylsulfonic acid.

[0218] Preferred monomers (a3) ​​include glycidyl methacrylate, maleic anhydride, and itaconic anhydride.

[0219] For monomer a4), a very preferred form is vinyl ester, vinyl ether, vinyl halide, vinylidene halide, vinyl compound having a heterocycle and an aromatic ring at the α-position. Again, without exclusion, some examples may be mentioned: vinyl acetate, vinyl formamide, vinylpyridine, ethyl vinyl ether, vinyl chloride, vinylidene chloride, and acrylonitrile.

[0220] For monomer a4), another highly preferred form is to use monomers having the following functional groups: hydroxyl, amide, isocyanate or amino.

[0221] Further particularly preferred examples of component a4) are hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, allyl alcohol, acrylamide, benzyl acrylate, benzyl methacrylate, phenyl acrylate, phenyl methacrylate, tert-butylphenyl acrylate, tert-butylphenyl methacrylate, phenoxyethyl acrylate, phenoxyethyl methacrylate, 2-butoxyethyl methacrylate, 2-butoxyethyl acrylate, dimethylaminoethyl methacrylate, dimethylaminoethyl acrylate, diethylaminoethyl methacrylate, diethylaminoethyl methacrylate, cyanoethyl methacrylate, cyanoethyl methacrylate, 6-hydroxyhexyl methacrylate, N-tert-butylacrylamide, N-hydroxymethylmethylacrylamide, N-(butoxymethyl)methylacrylamide, N-hydroxymethylacrylamide, N-(ethoxymethyl)acrylamide, N-isopropylacrylamide, tetrahydrofurfuryl acrylate, wherein this list is not exhaustive.

[0222] In another preferred embodiment, for component a4), an aromatic vinyl compound is used, wherein preferably the aromatic ring consists of C4 to C5 rings. 18 It may also include heteroatoms. Particularly preferred examples are styrene, 4-vinylpyridine, N-vinylphthalimide, methylstyrene, 3,4-dimethoxystyrene, and 4-vinylbenzoic acid, and this list is not exhaustive.

[0223] For polymerization, the monomers are selected such that the resulting polymer can be used as an industrially useful adhesive or PSA, and more specifically, such that the resulting polymer possesses adhesive or pressure-sensitive adhesive properties in the sense described in Donatas Satas's "Handbook of Pressure Sensitive Adhesive Technology" (van Nostrand, New York 1989). The desired glass transition temperature can also be controlled here by applying the Fox equation (E1) regarding the composition of the monomer mixture on which the polymerization is based. For PSA, the static glass transition temperature of the resulting polymer is advantageously below 15°C.

[0224] For heat-activated adhesives, in order to obtain a polymer glass transition temperature T ≥ 30°C... g,A Based on the above description, the monomers are very preferably selected in such a way that the quantitative composition of the monomer mixture is advantageously selected in such a way that the desired T of the polymer is obtained according to the Fox equation (E1). g,A Value (see TGFox, Bull. Am. Phys. Soc. 1 (1956) 123).

[0225]

[0226] In this equation, n represents the serial number of the monomer used, w n This represents the mass fraction (wt%) of the corresponding monomer n, and T g,n This indicates the glass transition temperature of the homopolymer of the corresponding monomer n, expressed in K.

[0227] For the preparation of adhesives, conventional free radical polymerization or controlled free radical polymerization is advantageously carried out. For polymerization via the free radical route, an initiator system that further includes other free radical initiators for polymerization, particularly azo or peroxide initiators that thermally decompose to form free radicals, is preferred. However, in principle, all initiators typical of acrylates and familiar to those skilled in the art are suitable. The generation of C-centered free radicals is described in Houben Weyl, Methoden der Organischen Chemie, Vol. E 19a, pp. 60-147. Preferably, these methods are used similarly.

[0228] Examples of free radical sources are peroxides, hydroperoxides, and azo compounds; some non-exclusive examples of typical free radical initiators can be given here, such as potassium peroxydisulfate, benzoyl peroxide, cumene hydroperoxide, cyclohexanone peroxide, di-tert-butyl peroxide, azobisisobutyronitrile, cyclohexylsulfonylacetyl peroxide, diisopropyl percarbonate, tert-butyl peroctanoate, and benzylpinacol. A very preferred form is 1,1'-azobis(cyclohexanecarboxynitrile) (from DuPont's Vazo 88). TM It acts as a free radical initiator.

[0229] The average molecular weight M of PSA obtained by free radical polymerization n Very preferably, they are selected such that they are in the range of 20,000-2,000,000 g / mol; particularly for further use as hot-melt pressure-sensitive adhesives, they are prepared with an average molecular weight M of 100,000-500,000 g / mol. n PSA.

[0230] Polymerization can be carried out in bulk, in the presence of one or more organic solvents, in the presence of water, or in a mixture of organic solvents and water. The aim here is to minimize the amount of solvent used.

[0231] Depending on the conversion and temperature, polymerization time ranges from 4 to 72 hours. The higher the selectable reaction temperature, in other words, the higher the thermal stability of the reaction mixture, the shorter the reaction time can be.

[0232] If low flammability is desirable, it can be achieved by adding flame retardants to the adhesive. These can be organic brominated compounds (if desired, along with synergists such as antimony trioxide); however, for halogen-free tapes, red phosphorus, organic phosphorus compounds, mineral compounds, or intumescent compounds such as ammonium polyphosphate, alone or in combination with synergists, are preferred. A full description of suitable flame retardants is given later.

[0233] To improve the cohesion (adhesion) between the adhesive and adjacent layers, the adhesive and / or adjacent layers can be subjected to corona treatment.

[0234] Primers can also be used to improve adhesion. Descriptions of commonly used primers can be found, for example, in Donatas Satas's "Handbook of Pressure Sensitive Adhesive Technology" (van Nostrand, 1989).

[0235] Composed of 300-1500g / m 2 Preferably 360-1500g / m 2 More preferably 600-1200g / m 2 The sixth layer, formed by an acrylate-based pressure-sensitive adhesive with a basis weight and / or a thickness of 400-1800 μm, preferably 500-1500 μm, more preferably 800-1200 μm, is preferably a foamed acrylate-based adhesive, for example, available from tesa under the name ACX. plus get.

[0236] ACX plus The series includes single-layer or multi-layer tapes with foamed acrylic-based adhesives.

[0237] This tape preferably has a carrier layer also known as a hard phase (rigid phase). The polymer base of the hard phase is preferably selected from polyvinyl chloride (PVC), polyethylene terephthalate (PET), polyurethane, polyolefin, polybutylene terephthalate (PBT), polycarbonate, polymethyl methacrylate (PMMA), polyvinyl butyral (PVB), ionomers, and mixtures of two or more of the above polymers. More preferably, the polymer base of the hard phase is selected from polyvinyl chloride, polyethylene terephthalate, polyurethane, polyolefin, and mixtures of two or more of the above polymers. The hard phase is essentially a polymer film whose polymer base is selected from the above materials. The "polymer film" is a thin, sheet-like, flexible, rollable web whose material base is essentially formed of one or more polymers.

[0238] In a broad sense, "polyurethane" is a polymeric substance in which repeating units are linked together by urethane moiety -NH-CO-O-.

[0239] "Polyolefin" is a polymer based on containing at least 50% by mass of repeating units of the general formula -[-CH2-CR1R2-]n-, where R1 is a hydrogen atom and R2 is a hydrogen atom or a straight-chain or branched saturated aliphatic or alicyclic group. When the hard-phase polymer base includes a polyolefin, these olefins are more preferably polyethylene, and more particularly ultra-high molar mass polyethylene (UHMWPE).

[0240] "Polymer base" is understood as the polymer that constitutes the largest weight fraction of all polymers present in the relevant layer or phase.

[0241] The thickness of the hard phase is particularly ≤150 μm. Preferably, the thickness of the hard phase is 10 to 150 μm, more preferably 30 to 120 μm, and even more particularly 50 to 100 μm, for example 70 to 85 μm. "Thickness" refers to the extent (size) of the relevant layer or phase along the z-coordinate of an imaginary coordinate system, where the planes spanned by the machine direction and the transverse direction relative to the machine direction form the xy plane. The thickness is determined by measuring at no fewer than five different locations on the relevant layer or phase, and then forming an arithmetic mean from the obtained measurements. Here, the thickness of the hard phase is measured according to DIN EN ISO 4593.

[0242] This tape may also have a soft phase, which comprises polymer foam, viscoelastic material, and / or elastomer material. The polymer base of the soft phase is preferably selected from polyolefins, polyacrylates, polyurethanes, and mixtures of two or more of the above polymers.

[0243] In its simplest form, tape consists of only a soft phase.

[0244] "Polymer foam" is a structure consisting of spherical or polyhedral pores filled with gas, the pores being defined by liquid, semi-liquid, high-viscosity, or solid pore walls; furthermore, the main component of the pore walls is a polymer or a mixture of two or more polymers.

[0245] "Viscoelastic materials" refer to materials that, in addition to exhibiting purely elastic characteristics (returning to their original state after external mechanical exposure), also exhibit characteristics of a viscous liquid, such as the occurrence of internal friction upon deformation. In particular, polymer-based PSAs are considered viscoelastic materials.

[0246] "Elastomer material" refers to a material that exhibits rubber-elastic behavior and can be repeatedly stretched to at least twice its length at 20°C, and immediately regains a size close to its initial size when the force required for stretching is removed.

[0247] Regarding the understanding of the terms "polymer base," "polyurethane," and "polyolefin," the above definitions apply. "Polyacrylate" is a polymer whose monomer base consists of at least 50% by weight acrylic acid, methacrylic acid, acrylates, and / or methacrylates, wherein acrylates and / or methacrylates are included at least proportionally, typically, and preferably in a proportion not less than 50%. More specifically, "polyacrylate" is a polymer obtainable by free radical polymerization of acrylic and / or methacrylic monomers, and optionally other copolymerizable monomers.

[0248] Particularly preferably, the polymer base of the soft phase is selected from polyolefins, polyacrylates, and mixtures of two or more of the above polymers. When polyolefins form a portion of the polymer base of the soft phase, they are preferably selected from polyethylene, ethylene-vinyl acetate copolymer (EVA), and mixtures of polyethylene and ethylene-vinyl acetate copolymer (PE / EVA blends). These polyethylenes can be different types of polyethylene, such as HDPE, LDPE, LLDPE, blends of these polyethylene types, and / or mixtures thereof.

[0249] In one embodiment, the soft phase includes a foam body and pressure-sensitive adhesive layers disposed above and below the foam layer, wherein the polymer base of the foam body is composed of one or more polyolefins, and the polymer base of the pressure-sensitive adhesive layer is composed of one or more polyacrylates. More preferably, the polymer base of the foam body is composed of one or more polyethylenes, ethylene-vinyl acetate copolymers, and mixtures of one or more polyethylenes and / or ethylene-vinyl acetate copolymers. Very preferably, the polymer base of the foam body is composed of one or more polyethylenes.

[0250] Polyolefin-based foams themselves have very little or no pressure-sensitive adhesiveness. Therefore, adhesion to a rigid phase or substrate is advantageously achieved via a pressure-sensitive adhesive layer. The foaming of the polyolefin-based starting material is preferably achieved by adding a foaming gas during a physical foaming process and / or by means of a chemical foaming agent, such as azodicarbonamide.

[0251] In another embodiment, the soft phase is a pressure-sensitive adhesive polymer foam, the polymer base of which consists of one or more polyacrylates. "Pressure-sensitive adhesive foam" means that the foam itself is a PSA, and therefore no additional pressure-sensitive adhesive layer is required. This is advantageous because there are fewer layers to be assembled during the manufacturing process, and the risk of separation at layer boundaries and other undesirable phenomena is reduced.

[0252] Polyacrylates are preferably obtained by copolymerization of functional monomers, at least in proportion, which are crosslinkable to epoxy groups. These monomers are more preferably those having acid groups (particularly carboxylic, sulfonic, or phosphonic acid groups) and / or hydroxyl and / or anhydride and / or epoxy and / or amine groups; monomers containing carboxylic acid groups are particularly preferred. It is particularly advantageous that the polyacrylate comprises copolymerized acrylic acid and / or methacrylic acid. All these groups are characterized by their crosslinkability to epoxy groups, thus making the polyacrylate advantageously suitable for thermal crosslinking with introduced epoxides.

[0253] In addition to acrylates and / or methacrylates having up to 30 carbon atoms, other monomers that can be used as comonomers for polyacrylates include, for example, vinyl esters of carboxylic acids having up to 20 carbon atoms, vinyl aromatic compounds having up to 20 carbon atoms, olefinic unsaturated nitriles, vinyl halides, vinyl ethers of alcohols having 1 to 10 carbon atoms, aliphatic hydrocarbons having 2 to 8 carbon atoms and one or two double bonds, or mixtures of these monomers.

[0254] The properties of the polyacrylates under discussion can be particularly affected by the variation in the glass transition temperature of the polymer due to different weight fractions of the monomers. The polyacrylates are preferably obtained from a monomer composition of:

[0255] a) Acrylates and / or methacrylates of the following formula

[0256] CH2=C(R I (COOR) II )

[0257] Where R I =H or CH3 and R II It is an alkyl group having 4-14 carbon atoms.

[0258] b) Alkenyl unsaturated monomers having functional groups of a defined type that are reactive with epoxy groups.

[0259] c) Additional acrylates and / or methacrylates and / or olefinic unsaturated monomers that may optionally copolymerize with component (a).

[0260] Preferably, the polyacrylate is obtained from a monomer composition in which the monomer of component (a) is present in a fraction of 45 to 99% by weight, the monomer of component (b) is present in a fraction of 1 to 15% by weight, and the monomer of component (c) is present in a fraction of 0 to 40% by weight (the figures are based on a mixture of monomers of a “base polymer” (i.e., without the addition of possible additives, such as resins, etc., to the finished polymer). In this case, the polymeric product has a glass transition temperature (DMA at low frequencies) of ≤15°C and pressure-sensitive adhesive properties.

[0261] The monomer of component (a) is more particularly a plasticizing and / or nonpolar monomer. Preferred monomers for use as monomer (a) are acrylates and methacrylates having an alkyl group consisting of 4 to 14 carbon atoms, more preferably 4 to 9 carbon atoms. Examples of such monomers are n-butyl acrylate, n-butyl methacrylate, n-pentyl acrylate, n-pentyl methacrylate, n-pentyl acrylate, n-hexyl acrylate, n-hexyl methacrylate, n-heptyl acrylate, n-octyl acrylate, n-octyl methacrylate, n-nonyl acrylate, isobutyl acrylate, isooctyl acrylate, isooctyl methacrylate, and their branched isomers, such as 2-ethylhexyl acrylate or 2-ethylhexyl methacrylate.

[0262] The monomer of component (b) is more particularly an olefinic unsaturated monomer having a functional group, particularly having a functional group capable of reacting with an epoxy group.

[0263] Preferably, the monomer used in component (b) is a monomer having a functional group selected from the following: hydroxyl, carboxyl, sulfonic acid or phosphonic acid, acid anhydride, epoxide, amine.

[0264] Particularly preferred examples of monomers for component (b) are acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, aconitic acid, dimethacrylic acid, β-acryloyloxypropionic acid, trichloroacrylic acid, vinylacetic acid, vinylphosphonic acid, itaconic acid, maleic anhydride, hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, 6-hydroxyhexyl methacrylate, allyl alcohol, glycidyl acrylate, and glycidyl methacrylate.

[0265] In principle, any vinyl-functionalized compound that can be copolymerized with component (a) and / or component (b) can be used as component (c). Monomers of component (c) can be used to adjust the properties of the resulting PSA.

[0266] The following are exemplary monomers of component (c):

[0267] Methyl acrylate, ethyl acrylate, propyl acrylate, methyl methacrylate, ethyl methacrylate, benzyl acrylate, benzyl methacrylate, sec-butyl acrylate, tert-butyl acrylate, phenyl acrylate, phenyl methacrylate, isobornyl acrylate, isobornyl methacrylate, tert-butylphenyl acrylate, tert-butylphenyl methacrylate, dodecyl methacrylate, isodecyl acrylate, lauryl acrylate, n-undecyl acrylate, stearyl acrylate, tridecyl acrylate, dodecyl acrylate, cyclohexyl methacrylate, cyclopentyl methacrylate, phenoxyethyl acrylate, phenoxyethyl methacrylate, 2-butoxy methacrylate 2-Butoxyethyl acrylate, 3,3,5-Trimethylcyclohexyl acrylate, 3,5-Dimethyladamantyl acrylate, 4-Cuylphenyl methacrylate, Ethyl cyanoacrylate, Ethyl cyanomethacrylate, 4-Biphenyl acrylate, 4-Biphenyl methacrylate, 2-Naphthyl acrylate, 2-Naphthyl methacrylate, Tetrahydrofurfuryl acrylate, Diethylaminoethyl acrylate, Diethylaminoethyl methacrylate, Dimethylaminoethyl acrylate, Dimethylaminoethyl methacrylate, 2-Butoxyethyl acrylate, 2-Butoxyethyl methacrylate, Methyl 3-Methoxyacrylate, 3-Methoxybutyl acrylate, Phenoxyethyl acrylate, Methyl Phenoxyethyl acrylate, 2-phenoxyethyl methacrylate, butyl diethylene glycol methacrylate, ethylene glycol acrylate, ethylene glycol monomethyl ether acrylate, methoxy polyethylene glycol methacrylate 350, methoxy polyethylene glycol methacrylate 500, propylene glycol monomethyl methacrylate, butoxydiethylene glycol methacrylate, ethoxytriethylene glycol methacrylate, octafluoropentyl acrylate, octafluoropentyl methacrylate, 2,2,2-trifluoroethyl methacrylate, 1,1,1,3,3,3-hexafluoroisopropyl acrylate, 1,1,1,3,3,3-hexafluoroisopropyl methacrylate, 2,2,3,3,3-pentafluoropropyl methacrylate, 2,2 3,4,4,4-Hexafluorobutyl acrylate, 2,2,3,3,4,4,4-Hepenobutyl acrylate, 2,2,3,3,4,4,4-Hepenobutyl methacrylate, 2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-Pentadecylfluorooctyl acrylate, Dimethylaminopropylacrylamide, Dimethylaminopropylmethacrylamide, N-(1-Methylundecyl)acrylamide, N-(n-Butoxymethyl)acrylamide, N-(Butoxymethyl)methacrylamide, N-(Ethoxymethyl)acrylamide, N-(n-Octadecyl)acrylamide, and N,N-dialkyl-substituted amides such as N,N-dimethylacrylamide, N,N-Dimethylmethacrylamide, N-Benzylacrylamide, N-Isopropylacrylamide, N-T-Butylacrylamide, N-T-Octylacrylamide, N-Hydroxymethylacrylamide, N-Hydroxymethylmethacrylamide, Acrylonitrile, Methacrylonitrile, Vinyl ethers such as vinyl methyl ether, ethyl vinyl ether, vinyl isobutyl ether, Vinyl esters such as vinyl acetate, Vinyl chloride, Vinyl halides, Vinylidene chloride, Vinylidene halide, Vinylpyridine, 4-Vinylpyridine, N-Vinylphthalimide, N-Vinyl lactam, N-Vinylpyrrolidone, Styrene, α-Methylstyrene and p-Methylstyrene, α-Butylstyrene, 4-n-Butylstyrene, 4-n-Decylstyrene, 3,4-Dimethoxystyrene, Macromonomers such as 2-Polystyrene-ethyl methacrylate (molecular weight M of 4000-13000 g / mol), w ), poly(methyl methacrylate)-ethyl methacrylate (2000-8000 g / mol M w ).

[0268] The monomers of component (c) may also be advantageously selected such that they include functional groups that support subsequent radiation-chemical crosslinking (e.g., by electron beam or UV). Suitable copolymerizable photoinitiators are, for example, benzoin acrylate and acrylate-functionalized benzophenone derivatives. Monomers that support crosslinking by electron bombardment are, for example, tetrahydrofurfuryl acrylate, N-tert-butylacrylamide, and allyl acrylate.

[0269] Polyacrylates (“polyacrylate” is understood in the context of this invention to be synonymous with “poly(meth)acrylate”) can be prepared by methods familiar to those skilled in the art, particularly advantageously by conventional free radical polymerization or controlled free radical polymerization. Polyacrylates can be prepared by copolymerizing monomer components using a conventional polymerization initiator and optionally a chain transfer agent, with polymerization carried out at conventional temperatures in bulk, in an emulsion such as in water or a liquid hydrocarbon, or in solution.

[0270] Polyacrylates are preferably prepared by polymerizing monomers in a solvent, more particularly in a solvent having a boiling range of 50-150°C, preferably 60-120°C, using a conventional amount (usually 0.01 to 5, more particularly 0.1 to 2 wt% (based on the total weight of the monomers)) of a polymerization initiator.

[0271] In principle, all conventional initiators familiar to the technician are suitable. Examples of free radical sources are peroxides, hydroperoxides, and azo compounds, such as benzoyl peroxide, cumene hydroperoxide, cyclohexanone peroxide, di-tert-butyl peroxide, cyclohexylsulfonylacetyl peroxide, diisopropyl percarbonate, tert-butyl peroctanoate, and benzylpinacol. A highly preferred procedure uses 2,2'-azobis(2-methylbutyronitrile) (from DuPont). 67 TM ) or 2,2'-azobis(2-methylpropionitrile) (2,2'-azobisisobutyronitrile; AIBN; from DuPont) 64 TM It acts as a free radical initiator.

[0272] Suitable solvents for preparing polyacrylates include alcohols such as methanol, ethanol, n-propanol and isopropanol, n-butanol and isobutanol, preferably isopropanol and / or isobutanol, and hydrocarbons such as toluene, more particularly mineral oils having a boiling range of 60 to 120°C. Other possibilities include ketones such as preferably acetone, methyl ethyl ketone, methyl isobutyl ketone, and esters such as ethyl acetate, and mixtures of solvents of these types, preferably mixtures including isopropanol, particularly in amounts of 2 to 15% by weight, preferably 3 to 10% by weight, based on the solvent mixture used.

[0273] Preferably, the preparation (polymerization) of the polyacrylate is followed by a concentration process, and further processing of the polyacrylate is carried out in the absence of substantially any solvent. The concentration of the polymer can be carried out in the absence of crosslinking agents and accelerators. However, it is also possible to add one of these types of compounds to the polymer even before concentration, in which case concentration is carried out in the presence of said substance.

[0274] After the concentration step, the polymer can be transferred to a compounding machine. If necessary, concentration and compounding can also be carried out in the same reactor.

[0275] Weight-average molecular weight M of polyacrylate w Preferably, the polymerization concentration is in the range of 20,000-2,000,000 g / mol; most preferably, in the range of 100,000-1,000,000 g / mol; and most preferably, in the range of 150,000-500,000 g / mol. For this purpose, it is advantageous to carry out polymerization in the presence of suitable chain transfer agents such as thiols, halogen compounds, and / or alcohols to set the desired average molecular weight.

[0276] The polyacrylate preferably has a K value of 30 to 90, more preferably 40 to 70, measured in toluene (1% concentration solution, 21°C). According to Fickentscher, the K value is a measure of the polymer's molecular weight and viscosity.

[0277] Particularly suitable are polyacrylates with a narrow molecular weight distribution (polydispersity PD < 4). Despite their relatively low molecular weight after crosslinking, these materials exhibit particularly good shear strength. The relatively low polydispersity also facilitates melt processing, as the flow viscosity is lower than that of polyacrylates with a wider range of applications while maintaining substantially the same application properties. Narrow-range poly(meth)acrylates can be advantageously prepared by anionic polymerization or by controlled radical polymerization, the latter being particularly suitable. Examples of such polyacrylates prepared by the RAFT method are described in US 6,765,078 B2 and US 6,720,399 B2. Such polyacrylates can also be prepared via N-oxygenation, as described, for example, in EP 1 311 555 B1. Furthermore, advantageously, atom transfer radical polymerization (ATRP) can be used to synthesize a narrow range of polyacrylates, wherein the initiators used preferably comprise monofunctional or bifunctional secondary or tertiary halides, and said halides are extracted using complexes of Cu, Ni, Fe, Pd, Pt, Ru, Os, Rh, Co, Ir, Ag, or Au. Various possibilities for ATRP are described in the specifications US 5,945,491 A, US 5,854,364 A, and US 5,789,487 A.

[0278] Preferably, the monomers used to prepare the polyacrylate include, in proportion, functional groups suitable for linkage reactions with epoxy groups. This advantageously allows the polyacrylate to undergo thermal crosslinking via reaction with epoxides. In particular, linkage reactions are understood as addition and substitution reactions. Thus, preferably, functional group-carrying building units are linked to epoxy group-carrying building units, more particularly in the sense that the functional group-carrying polymer building units are crosslinked via linking bridges comprising crosslinking agent molecules carrying epoxy groups. The epoxy group-containing substances are preferably polyfunctional epoxides, in other words, those having at least two epoxy groups; thus, preferably, the overall result is an indirect linkage of functional group-carrying building units.

[0279] Polyacrylates are preferably crosslinked via a linkage reaction of their contained functional groups with a thermal crosslinking agent (particularly in the sense of addition or substitution). All thermal crosslinking agents can be used that not only ensure a sufficiently long processing life (meaning no gelling during processing operations) but also cause the polymer to rapidly post-crosslink to the desired degree of crosslinking at temperatures below the processing temperature, more particularly at room temperature. For example, combinations of carboxyl-containing, amino-containing, and / or hydroxyl-containing polymers with isocyanates as crosslinking agents, more particularly aliphatic isocyanates as described in EP 1 791 922 A1, or amine-deactivated triisocyanates are possible.

[0280] More specifically, suitable isocyanates are trimer derivatives such as MDI [4,4'-methylene di(phenyl isocyanate)], HDI [hexamethylene diisocyanate, 1,6-hexanediisocyanate] and / or IPDI [isophorone diisocyanate, 5-isocyano-1-isocyanomethyl-1,3,3-trimethylcyclohexane], examples of which are of type [type]. N3600 and XP2410 (each BAYER AG: aliphatic polyisocyanate, low viscosity HDI trimer). Also suitable is the micronized trimer of surface-deactivated IPDI dispersion BUEJ. (now is) (BAYER AG).

[0281] However, other isocyanates are also suitable for crosslinking in principle, such as Desmodur VL 50 (MDI-based polyisocyanate, Bayer AG), Basonat F200WD (aliphatic polyisocyanate, BASF AG), Basonat HW100 (water-emulsifiable multifunctional HDI-based isocyanate, BASF AG), Basonat HA300 (urethane-modified polyisocyanate based on HDI isocyanurate, BASF), or Bayhydur VPLS2150 / 1 (hydrophilically modified IPDI, Bayer AG).

[0282] Preferably, a thermal crosslinking agent such as a trimeric isocyanate is used in 0.1 to 5% by weight, more particularly in 0.2 to 1% by weight, based on the total amount of the polymer to be crosslinked.

[0283] The thermal crosslinking agent preferably comprises at least one substance containing an epoxy group. The substance containing an epoxy group is more particularly a polyfunctional epoxide, in other words, those having at least two epoxy groups; thus, the overall result is an indirect connection of building units carrying functional groups. The substance containing an epoxy group can be an aromatic compound and can be an aliphatic compound.

[0284] Ideally suited for use with oligomers of polyfunctional epoxides such as epichlorohydrins, polyhydroxy alcohols (more particularly ethylene glycol, propylene glycol and butylene glycol, polyethylene glycol, thiodiglycol, glycerol, pentaerythritol, sorbitol, polyvinyl alcohol, polyallyl alcohol, etc.), epoxy ethers of polyhydroxyphenols (more particularly resorcinol, hydroquinone, bis(4-hydroxyphenyl)methane, bis(4-hydroxy-3-methylphenyl)methane, bis(4-hydroxy-3,5-dibromophenyl)methane, bis(4-hydroxy-3,5-dibromophenyl)methane, bis(4-hydroxy-3,5-dibromophenyl)methane, etc.). 1,1-bis(4-hydroxyphenyl)methane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxy-3-methylphenyl)propane, 2,2-bis(4-hydroxy-3-chlorophenyl)propane, 2,2-bis(4-hydroxy-3,5-dichlorophenyl)propane, bis(4-hydroxyphenyl)phenylmethane, bis(4-hydroxyphenyl)diphenylmethane, bis(4-hydroxyphenyl)-4'-tolylmethane, 1,1-bis(4- Epoxy ethers of hydroxyphenyl(2,2,2-trichloroethane), bis(4-hydroxyphenyl)(4-chlorophenyl)methane, 1,1-bis(4-hydroxyphenyl)cyclohexane, bis(4-hydroxyphenyl)cyclohexylmethane, 4,4'-dihydroxybiphenyl, 2,2'-dihydroxybiphenyl, 4,4'-dihydroxydiphenyl sulfone, and their hydroxyethyl ethers; phenol-formaldehyde condensation products such as phenolic alcohols, phenolic resins, etc.; S-containing epoxides and N-containing epoxides (e.g., N,N... -Diglycidyl aniline, N,N'-dimethyldiglycidyl-4,4-diaminodiphenylmethane), and epoxides, glycidyl esters, and polyglycidyl esters prepared by conventional methods from monounsaturated or polyunsaturated carboxylic acid esters of unsaturated alcohols, which may be obtained by polymerization or copolymerization of glycidyl esters of unsaturated acids or by other acidic compounds (cyanuric acid, diglycidyl sulfides, cyclic trimethylene trisulfone and / or its derivatives, and others).

[0285] Very suitable ethers include, for example, 1,4-butanediol diglycidyl ether, polyglycerol-3-glycidyl ether, cyclohexanediethanol diglycidyl ether, glycerol triglycidyl ether, neopentyl glycol diglycidyl ether, pentaerythritol tetraglycidyl ether, 1,6-hexanediol diglycidyl ether, polypropylene glycol diglycidyl ether, trimethylolpropane triglycidyl ether, bisphenol A diglycidyl ether, and bisphenol F diglycidyl ether.

[0286] A crosslinking agent-accelerator system (“crosslinking system”) (e.g., described in EP 1 978 069 A1) is particularly preferred to obtain more effective control over processing life, crosslinking kinetics, and the degree of crosslinking. This crosslinking agent-accelerator system comprises at least one epoxy-containing substance as a crosslinking agent and at least one substance as an accelerator that has a promoting effect on the crosslinking reaction of the epoxy-functionalized compound at a temperature below the melting temperature of the polymer to be crosslinked.

[0287] The promoters used are more preferably amines (formally interpreted as substituted products of ammonia; in the following formula, these substituents are represented by "R" and particularly include alkyl and / or aryl groups and / or other organic groups), and more particularly preferably those amines that do not react or only slightly react with the building units of the polymer to be crosslinked.

[0288] In principle, primary amines (NRH2), secondary amines (NR2H), and tertiary amines (NR3) can be selected as accelerators, as well as those having two or more primary and / or secondary and / or tertiary amine groups. However, particularly preferred accelerators are tertiary amines, such as triethylamine, triethylenediamine, benzyldimethylamine, dimethylaminomethylphenol, 2,4,6-tris(N,N-dimethylaminomethyl)phenol, and N,N'-bis(3-(dimethylamino)propyl)urea. Polyfunctional amines such as diamines, triamines, and / or tetraamines can also be advantageously used as accelerators. For example, diethylenetriamine, triethylenetetramine, and trimethylhexamethylenediamine are very suitable.

[0289] Furthermore, amino alcohols are preferably used as promoters. Secondary and / or tertiary amino alcohols are particularly preferred, wherein, in the case of two or more amine functional groups per molecule, at least one, preferably all, amine functional groups are secondary and / or tertiary. As preferred amino alcohol promoters, triethanolamine, N,N-bis(2-hydroxypropyl)ethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, 2-aminocyclohexanol, bis(2-hydroxycyclohexyl)methylamine, 2-(diisopropylamino)ethanol, 2-(dibutylamino)ethanol, N-butyldiethanolamine, N-butylethanolamine, 2-[bis(2-hydroxyethyl)amino]-2-(hydroxymethyl)-1,3-propanediol, 1-[bis(2-hydroxyethyl)amino]-2-propanol, triisopropanolamine, 2-(dimethylamino)ethanol, 2-(diethylamino)ethanol, 2-(2-dimethylaminoethoxy)ethanol, N,N,N'-trimethyl-N'-hydroxyethylbisaminoethyl ether, N,N,N'-trimethylaminoethylethanolamine and / or N,N,N'-trimethylaminopropyl-ethanolamine.

[0290] Other suitable accelerators include pyridine, imidazoles (e.g., 2-methylimidazolium), and 1,8-diazabicyclo[5.4.0]undec-7-ene. Alicyclic polyamines can also be used as accelerators. Suitable accelerators also include phosphorus-based accelerators such as phosphine and / or... Compounds, such as triphenylphosphine or tetraphenylphosphine Tetraphenylborate.

[0291] It is also possible that even polymeric foams with inherent pressure-sensitive adhesive properties (having a polymer base composed of polyacrylate) may be coated with PSA on their upper and / or lower sides, wherein the polymer base of the PSA is preferably also composed of polyacrylate. Alternatively, different and / or differently pretreated adhesive layers (in other words, for example, heat-activated layers and / or pressure-sensitive adhesive layers based on polymers different from poly(meth)acrylate) can be laminated to form foamed layers. Suitable base polymers are natural rubber, synthetic rubber, acrylate block copolymers, vinyl aromatic block copolymers, particularly styrene block copolymers, EVA, polyolefins, polyurethanes, polyvinyl ethers, and silicones. Preferably, these layers do not contain a significant fraction of migratable components that are compatible with the foamed layer material well enough to diffuse into the foamed layer in significant amounts and alter its properties.

[0292] Generally, the soft phase of an adhesive tape may include at least one tackifying resin. Suitable tackifying resins include, in particular, aliphatic, aromatic, and / or alkyl aromatic hydrocarbon resins, monomer-based hydrocarbon resins, hydrogenated hydrocarbon resins, functionalized hydrocarbon resins, and natural resins. The tackifying resin is preferably selected from: pinene resins, indene resins, and rosin, their disproportionated, hydrogenated, polymerized, and / or esterified derivatives and salts, terpene resins and terpene-phenolic resins, and C5 hydrocarbon resins, C9 hydrocarbon resins, and other hydrocarbon resins. Combinations of these and other resins can also be advantageously used to adjust the properties of the resulting adhesive as needed. More preferably, the tackifying resin is selected from terpene-phenolic resins and rosin esters.

[0293] The soft phase of the tape may include one or more fillers. The fillers may be present in one, two or more layers of the soft phase.

[0294] Preferably, the soft phase comprises a polymer foam, and the polymer foam comprises partially or fully expanded microspheres, particularly if the polymer base of the polymer foam comprises one or more polyacrylates, and very preferably if the polymer base of the polymer foam consists of one or more polyacrylates. Microspheres are elastic hollow spheres with a thermoplastic polymer shell; therefore, they are also called expandable polymer microspheres or hollow microspheres. These spheres are filled with a low-boiling-point liquid or liquefied gas. Shell materials used particularly include polyacrylonitrile, polyvinyl chloride (PVDC), polyvinyl chloride (PVC), polyamide, or polyacrylates. More suitably, the low-boiling-point liquid particularly includes lower alkanes such as isobutane or isopentane, which are encapsulated as liquefied gases within the polymer shell under pressure. Physical action on the microspheres, such as by exposure to heat, particularly by supplying or generating heat (e.g., by ultrasound or microwave radiation), first causes softening of the outer polymer shell, while the liquid foaming gas within the shell undergoes a transformation to its gaseous state. Under a given pairing (combination) of pressure and temperature (also known as critical pairing), microspheres undergo irreversible and three-dimensional expansion. Expansion ends when the internal pressure matches the external pressure. As the polymer shell is retained, the result is a closed-cell foam.

[0295] Many types of microspheres are commercially available, such as Expansion DU (dry, unexpanded) from Akzo Nobel, which differ mainly in their size (6-45 μm diameter in the unexpanded state) and the onset temperature required for expansion (75°C to 220°C).

[0296] Also available are unexpanded microsphere products in the form of an aqueous dispersion having a solids fraction or microsphere fraction of about 40-45% by weight; additionally, polymer-bonded microspheres (masterbatches) are available (e.g., in ethylene-vinyl acetate at a microsphere concentration of about 65% by weight). Furthermore, so-called microsphere slurry systems are available, in which the microspheres are in the form of an aqueous dispersion having a solids fraction of 60-80% by weight. Like DU products, microsphere dispersions, microsphere slurries, and masterbatches are suitable for foaming polymeric foams present in the soft phase of tapes.

[0297] Particularly preferably, the polymer foam comprises microspheres having a diameter of 3 μm-40 μm, more particularly 5 μm-20 μm, at 25°C in its unexpanded state, and / or having a diameter of 10 μm-200 μm, more particularly 15 μm-90 μm, after expansion.

[0298] Preferably, the polymer foam contains up to 30% by weight of microspheres, more particularly between 0.5% and 10% by weight, based on the total mass of the polymer foam in each case.

[0299] Preferably, the soft phase of the tape, which is a polymer foam (to the extent that the phase comprises a polymer foam), is characterized by having substantially no open-cell cavities. Particularly preferably, the proportion of cavities in the polymer foam that do not have their own polymer shells (i.e., the proportion of open-cell cavities) does not exceed 2% by volume, and more particularly, does not exceed 0.5% by volume. Therefore, the polymer foam is preferably a closed-cell foam.

[0300] The soft phase of the tape may optionally include powdered and / or granular fillers, dyes and pigments, particularly abrasives and reinforcing fillers such as chalk (CaCO3), titanium dioxide, zinc oxide and carbon black, and include them in high fractions (i.e. 0.1 to 50% by weight, based on the total mass of the soft phase).

[0301] Other possible components of the soft phase may include low-flammability fillers, such as ammonium polyphosphate; conductive fillers, such as conductive carbon black, carbon fibers, and / or silver-coated beads; thermally conductive materials, such as boron nitride, alumina, and silicon carbide; ferromagnetic additives, such as iron(III) oxides; other additives for increasing volume, such as expanders, solid glass beads, hollow glass beads, carbonized microspheres, hollow phenolic microspheres, and microspheres made of other materials; silica, silicates, organic renewable raw materials such as wood flour, organic and / or inorganic nanoparticles, and fibers; aging inhibitors, light stabilizers, anti-ozone agents, and / or compounding agents. The aging inhibitors that can be used are preferably not only the main inhibitors such as 4-methoxyphenol or 1076, and for co-aging inhibitors such as those from BASF TNPP or 168 (optionally in combination with each other). Other aging inhibitors that may be used are hydroquinone methyl ether and phenothiazine (C radical scavengers) in the presence of oxygen and oxygen itself.

[0302] The thickness of the soft phase is preferably 200-1800 μm, more preferably 300-1500 μm, and more particularly 400-1000 μm. The thickness of the soft phase is determined according to ISO 1923.

[0303] Joining a hard phase and a soft phase, or layers provided in the hard phase and / or soft phase, to form an adhesive tape can be done, for example, by lamination or co-extrusion. It is possible for the hard and soft phases to be joined directly (in other words, unmittelbar) to each other. It is also possible to provide one or more adhesion-promoting layers between the hard and soft phases. Furthermore, the tape may include additional layers.

[0304] Preferably, at least one, more preferably multiple, and very particularly preferably all layers to be bonded are pretreated by corona (using air or nitrogen), plasma (air, nitrogen or other reactive gases, or reactive compounds that can be used as aerosols), or flame pretreatment techniques.

[0305] Preferably, all layers in the die-cut part have the same shape and size and are arranged equally (overlappingly).

[0306] Typical sizes of die-cut parts that allow for the closure of many smaller holes are represented by (circular) discs with diameters of 10-100 mm, more particularly 20-60 mm, and especially 30-40 mm.

[0307] The method of the present invention for closing openings, such as holes, particularly holes in a vehicle body, using the die-cutting part of the present invention simply involves applying the die-cutting part to the opening to be closed in such a way that the opening is completely covered by the die-cutting part.

[0308] It is preferable to apply the die-cut parts concentrically to the opening to be closed.

[0309] The contour of the die-cut part advantageously corresponds to the contour of the opening to be closed. In this way, the overlap (protrusion) of the layers of the die-cut part is symmetrical. The overlap (protrusion) is preferably between 3 and 20 mm, more preferably between 5 and 10 mm.

[0310] The die-cut parts of the present invention are superior to known solutions in the prior art, especially under enhanced mechanical stress.

[0311] The characteristics of die-cut parts are:

[0312] Very high flame retardancy

[0313] • Very high load capacity / tear resistance / puncture resistance

[0314] Excellent moisture sealing / moisture blocking

[0315] Excellent noise sealing / sound damping

[0316] • Repaintable

[0317] PVC adhesion

[0318] According to an advantageous embodiment of the invention, the die-cut part has a puncture resistance of 200 to 2000 N.

[0319] The surface of the die-cut parts is attractive and smooth in terms of optical and tactile quality, and therefore has good repaintability.

[0320] Test methods

[0321] (Unless otherwise stated) Measurements were performed under test conditions of 23±1℃ and 50±5% relative humidity.

[0322] Molar mass Mn and weight-average molar mass Mw, as well as polydispersity PD

[0323] The number-average molar mass Mn, weight-average molar mass Mw, and polydispersity PD figures in this specification refer to determinations by gel permeation chromatography (GPC). 100 μl of clarified and filtered sample (sample concentration 4 g / L) was analyzed. The eluent used was tetrahydrofuran containing 0.1% (v / v) trifluoroacetic acid. Measurements were performed at 25°C.

[0324] The pre-column used was a PSS-SDV type column, 10μm. 8.0mm*50mm (The following statements are made in the following order: type, particle size, porosity, inner diameter*length; Separation was performed using the following combination: PSS-SDV column, 10 μm. as well as and Each column was 8.0 mm × 300 mm (from PolymerStandards Service; measured using a Shodex RI71 differential refractometer). Flow rate was 1.0 ml / min.

[0325] Calibration was performed using the commercially available ReadyCal-Kit poly(styrene)high from PSS Polymer Standards Service GmbH, Mainz. It was universally converted to polymethyl methacrylate (PMMA) using Mark-Houwink parameters K and α, and the data were reported in PMMA mass equivalents.

[0326] K value

[0327] The principle of this method is based on the capillary-viscosity method for determining the relative viscosity of a solution. For this purpose, the test substance is dissolved in toluene by shaking for 30 minutes to obtain a 1% concentration solution. The flow time is measured in a Vogel-Ossag viscometer at 25°C, and the relative viscosity of the sample solution is thus determined relative to the viscosity of the pure solvent. The K value (K = 1000k) can be read from a table using the method of Fikentscher [PEHinkamp, ​​Polymer, 1967, 8, 381].

[0328] Glass transition temperature

[0329] The glass transition temperature was determined using dynamic scanning calorimetry (DSC). This was performed as follows: 5 mg of untreated polymer sample was weighed into an aluminum crucible (25 μL volume) and sealed with a perforated lid. Measurements were taken using a Netzsch DSC 204F1. For inertization, the operation was conducted under nitrogen. The sample was first cooled to -150 °C, then heated to +150 °C at a heating rate of 10 K / min, and then cooled again to -150 °C. The subsequent second heating curve was run again at 10 K / min, and the change in heat capacity was recorded. The glass transition is considered as a step in the temperature spectrum.

[0330] The glass transition temperature is evaluated as follows (see Figure 2 ):

[0331] Tangents are applied to the baselines of the thermographs before ① and after ② the step, respectively. In the region of the step, the equilibrium line ⑤ is placed parallel to the ordinate in such a way that it intersects the two tangents, specifically to form two equal regions ③ and ④ (between the tangent, the equilibrium line, and the measurement plot, respectively). The intersection of the equilibrium line and the measurement plot, thus positioned, gives the glass transition temperature.

[0332] Peel adhesion (bonding strength)

[0333] Peel adhesion was determined as follows (according to AFERA ​​5001). The specified substrate used was a galvanized steel sheet with a thickness of 2 mm (available from Rocholl GmbH). The adhesive sheet element under study was cut into pieces 20 mm wide and approximately 25 cm long, with gripping parts provided, and then immediately pressed against the selected substrate five times using a 4 kg steel roller at a forward rate of 10 m / min. Immediately afterward, the adhesive sheet element was peeled from the substrate at a speed of v = 300 mm / min using a tensile tester (Zwick) at an angle of 180°, and the force required to achieve this at room temperature was recorded. The recorded value (in N / cm) was obtained as the average of three individual measurements.

[0334] Puncture resistance

[0335] For puncture resistance, the maximum load force on the die-cut part bonded to the hole at the puncture point is measured (e.g., for hole closures in the automotive industry).

[0336] Holes in a metal sheet are sealed using a circular die-cut part. Testing is performed immediately after bonding or after specified storage conditions. The maximum force recorded is reported as a puncture resistance result in N. The maximum force on the puncture test specimen is determined using a tensile testing machine. The tensile testing machine loads the bonded die-cut part centrally with a die head that moves downwards at 300 mm / min until a penetration depth of 20 mm is achieved.

[0337] This method is based on the use of a tensile testing machine with a nail (pointed object) clamped in its upper force recorder. The nail moves at a constant speed (300 mm / min) toward a horizontally positioned hole in a metal plate, which is then closed by a die-cutting. The selected hole is a circular cut with a diameter of 30 mm. The steel plate is 0.7 mm thick and placed on a ring such that the nail passes through the hole by 20 mm when pressing against the hole closure. The nail's point (end point) is rounded and represents the head of an ISO 8677 flat round screw (Flachrundschraube) with a diameter of 20 mm and an arc height of 3 mm, which has been welded to the recorder. The force required to press the nail through the hole by 20 mm is measured. When the metal plate adhesion is very good, this value relates to the tensile elongation properties of the layered element in both the longitudinal and transverse directions.

[0338] Place the die-cut piece (circular, 50mm in diameter) to be tested as centered as possible and without air pockets over the hole in the metal plate, and roll it using a 4kg steel roller (back and forth five times at 10m / min across the entire width of the die-cut piece). Unless otherwise specified, the test should be performed less than 10 minutes after bonding (immediate test).

[0339] The test can be performed on either the carrier side or the adhesive side. Unless otherwise specified, it is performed on the carrier side, meaning the carrier side of the die-cut part is facing upwards.

[0340] The test specimen is placed and secured on the specimen holder as follows: the die-cut piece is centered on the holder and centered below the die head. The machine is then started at a speed of 300 mm / min, pressing the die-cut piece downwards through the hole in the metal plate. The test ends when a penetration depth of 20 mm is reached, even if the test specimen has only been pressed in but not yet punctured.

[0341] Puncture resistance is the average of three individual results.

[0342] If the die-cut part has not been punctured (pierced) or if the adhesive has loosened, the result is reported with a preface adding "greater than / equal to".

[0343] Combustion test

[0344] A die-cut piece (10) with a die-cut diameter of 50 mm is concentrically applied to a cathodic electrophoretic coated metal plate (20) containing a circular hole with a hole diameter of 30 mm.

[0345] The die-cut parts are pre-treated in an oven at 160°C for 30 minutes.

[0346] The die-cut parts are then allowed to cool to room temperature. This waiting time includes a span of at least two hours.

[0347] A flame is applied to the outer surface of the die-cut part using a Bunsenbrenner (40) to generate a temperature of 1000°C + / -100°C at a K-type temperature sensor (30) located directly and centrally in front of the die-cut part.

[0348] There are vertical tests (sample vertical, flame horizontal) and horizontal tests (sample horizontal, flame vertical).

[0349] Figure 3a Show vertical test, and Figure 3b Display level test.

[0350] Below, based on the accompanying drawings, the die-cut parts for permanently sealing holes, particularly holes in metal sheets or plastic parts of automobile bodies, will be described in more detail, without any intention of having any restrictive effect.

[0351] Figure 1 Show openings, such as holes, in the body to be closed, and the state after the holes are closed.

[0352] As a result of its construction, the main body 20 includes a hole 50 to be closed.

[0353] Therefore, the die-cut part 10 of the carrier having the following structure is fixed to the hole 50 in such a way that the hole 50 is completely covered by the die-cut part 10.

[0354] 1. Needle-punched nonwovens

[0355] 12 Adhesives

[0356] 2. Lay the glass fabric

[0357] 3. Adhesives

[0358] 4 Aluminum foil

[0359] 5. Foamed acrylic adhesives

[0360] The area of ​​the die-cut part 10 is larger than the area of ​​the hole 50 to be closed, so that the hole 50 is closed over its entire area.

[0361] The invention is described in more detail below with reference to two embodiments, but is not intended to limit the invention thereto. Example

[0362]

[0363]

[0364]

[0365] Comparative Example

[0366] In the comparative examples, layer 1, the PAN needle-punched nonwoven fabric, and optional layers 12 and 3 were replaced by the corresponding layers listed in the table and were subjected to the same vertical burning test (temperature 1000°C, for a maximum of at least 10 minutes).

[0367] It was found that no layer produced die-cut parts that passed the combustion test with comparable (equally good) results. Here, failure is defined as the breakthrough of flame through the hole.

[0368]

[0369]

[0370] *: BW: Basis Weight

[0371] The advantages of the die-cut parts of the present invention compared with the prior art are as follows:

[0372] • Fire resistance in two burning tests for a duration of at least 10 minutes and a temperature of up to 1000°C.

[0373] Low-temperature impact resistance

[0374] Clean adhesion with no adhesive extrusion.

[0375] • The flame-retardant foam layer exhibits sufficient adhesion to acrylate-based pressure-sensitive adhesives (in contrast to many comparable products, there is no cohesive breakage between layers).

Claims

1. Die-cut parts, A carrier consisting of the following components: At least one first layer is formed of a needle-punched nonwoven fabric having a thickness of 1 to 6 mm, wherein the needle-punched nonwoven fabric comprises mechanically needle-punched, oxidized, and thermally stable polyacrylonitrile (PAN) fibers. Optionally, at least one second layer is formed of a pressure-sensitive adhesive in the form of a laminated adhesive. At least one third layer, which consists of a concentration of 30 to 200 g / m 2 The base is formed by weaving or laying glass fabric. Optionally, at least one fourth layer is formed of a pressure-sensitive adhesive in the form of a laminated adhesive. At least one fifth layer, which is formed of a metal layer having a thickness of 5 to 40 μm, and At least one sixth layer, which consists of a concentration of 300 to 1800 g / m³ 2 The basis weight and / or thickness of an additional acrylate-based pressure-sensitive adhesive are formed.

2. The die-cut part according to claim 1, Its features The die-cut part is used to permanently seal the hole.

3. The die-cut part according to claim 2, Its features The hole is a hole in a metal plate or in a plastic component.

4. The die-cut part according to claim 1, Its features The carrier is composed of a laminate arranged in a specified layer sequence.

5. The die-cut part according to claim 1, Its features The second layer consists of materials with a concentration of 5 to 50 g / m 2 A pressure-sensitive adhesive in the form of a laminated adhesive is formed by coating a unit area weight of the adhesive.

6. The die-cut part according to claim 1, Its features The fourth layer consists of materials with a concentration of 5 to 50 g / m 2 A pressure-sensitive adhesive in the form of a laminated adhesive is formed by coating a unit area weight of the adhesive.

7. The die-cut part according to claim 1, Its features The sixth layer consists of materials with a concentration of 360 to 1500 g / m³. 2 The base weight is formed by another acrylate-based pressure-sensitive adhesive.

8. The die-cut part according to claim 1, Its features The sixth layer is formed of an additional acrylate-based pressure-sensitive adhesive having a thickness of 800 to 1500 μm.

9. The die-cut part according to claim 1, Its features The metal layer has a thickness of 8 to 20 μm.

10. The die-cut part according to claim 9, Its features The metal layer has a thickness of 10 to 12 μm.

11. The die-cut part according to any one of claims 1 to 10, Its features The metal layer is a rolled metal foil.

12. The die-cut part according to claim 11, Its features The metal foil is aluminum foil.

13. The die-cut part according to any one of claims 1 to 10, Its features The third layer of woven or laid glass fabric has a strength of 60 and 120 g / m². 2 The base weight between.

14. The die-cut part according to claim 13, Its features The third layer of woven or laid glass fabric has a strength of 70 to 100 g / m². 2 The base weight between.

15. The die-cut part according to claim 13, Its features The third layer of woven or laid glass fabric has a density of 80 and 90 g / m². 2 The base weight between.

16. The die-cut part according to any one of claims 1 to 10, Its features The glass fabric is woven or laid within the polymer layer.

17. The die-cut part according to claim 16, Its features The polymer layer is a polyurethane-based polymer layer.

18. The die-cut part according to claim 16, Its features The woven or laid glass fabric is located within a polymer layer, such that all the filaments of the woven or laid glass fabric are surrounded by the polymer as completely as possible.

19. The die-cut part according to any one of claims 1 to 10, Its features In the third layer of woven or laid glass fabric, the warp and / or weft yarn count is 20 to 40 / cm.

20. The die-cut part according to claim 19, Its features The warp yarn count and / or weft yarn count is 25 to 30 / cm.

21. The die-cut part according to any one of claims 1 to 10, Its features An adhesive layer in the form of a laminated adhesive exists between the first layer of the needle-punched nonwoven fabric and the third layer in the form of a woven or laid glass fabric, and / or between the third layer in the form of a woven or laid glass fabric and the metal layer.

22. The die-cut part according to claim 21, Its features The adhesive layer in the form of a laminated adhesive has a content of 5 to 50 g / m 2 The coating weight per unit area.

23. The die-cut part according to claim 21, Its features The adhesive layer in the form of a laminated adhesive has a content of 7 to 20 g / m 2 The coating weight per unit area.

24. The die-cut part according to any one of claims 1 to 10, Its features From 300 to 1800 g / m 2 The sixth layer, formed by the additional pressure-sensitive adhesive, is a foamed acrylic-based adhesive.

25. The die-cut part according to any one of claims 1 to 10, Its features Apply the die-cut parts concentrically to the opening to be closed.

26. The die-cut part according to any one of claims 1 to 10, Its features The profile of the die-cut part corresponds to the profile of the opening to be closed.

27. The die-cut part according to claim 26, Its features The profile of the die-cut part corresponds to the profile of the opening to be closed, such that the overlap allowance is between 1 and 20 mm.

28. The die-cut part according to claim 26, Its features The profile of the die-cut part corresponds to the profile of the opening to be closed, such that the overlap allowance is between 5 and 10 mm.

29. The die-cut part according to any one of claims 1 to 10, Its features At least the first, second, third, fourth, fifth, and sixth layers exist simultaneously.

30. The die-cut part according to any one of claims 1 to 10, Its features The first layer has a thickness of 2 mm to 4 mm.

31. The die-cut part according to any one of claims 1 to 10, Its features The first layer has a thickness of 3 mm.

32. The die-cut part according to any one of claims 1 to 10, Its features The needle-punched nonwoven fabric has a basis weight of 600 to 1200 g / m².

33. The die-cut part according to claim 32, Its features The needle-punched nonwoven fabric has a basis weight of 800 to 900 g / m².

34. The die-cut part according to any one of claims 1 to 10, Its features The needle-punched nonwoven fabric contains up to 80% by weight of polyacrylonitrile (PAN) fibers.

35. The die-cut part according to claim 34, Its features The needle-punched nonwoven fabric contains up to 90% by weight of polyacrylonitrile (PAN) fibers.

36. The die-cut part according to claim 34, Its features The needle-punched nonwoven fabric contains up to 95% by weight of polyacrylonitrile (PAN) fibers.

37. The die-cut part according to claim 34, Its features The needle-punched nonwoven fabric is composed of polyacrylonitrile (PAN) fibers.

38. The die-cut part according to any one of claims 1 to 10, Its features The needle-punched nonwoven fabric contains a flame retardant.

39. The die-cut part according to claim 38, Its features The needle-punched nonwoven fabric contains at least 1% by weight of flame retardant.

40. The die-cut part according to claim 39, Its features The needle-punched nonwoven fabric contains less than 10% by weight of flame retardant.

41. The die-cut part according to claim 38, Its features The flame retardant includes one or more synergists.

42. The die-cut part according to claim 38, Its features The flame retardant includes a) 60 to 99% by weight of one or more compounds selected from dialkylphosphinates of formula F2 and ammonium polyphosphates. (R III R IV (O)P-O (-) ) m M (m+ )(F2), Where R III and R IV They are the same or different, and are straight-chain or branched C1 to C6 alkyl groups; M is Mg, Ca, Al, Sb, Sn, Ge, Ti, Fe, Zr, Zn, Ce, Bi, Sr, Mn, Li, Na, K, or a protonated nitrogen base; and m is a natural number from 1 to 4. as well as b) 1 to 40% by weight of one or more synergists, The percentage by weight is based on the total weight of the flame retardants and is added together to reach 100 by weight.

43. The die-cut part according to any one of claims 1 to 10, Its features The number of warp and / or weft yarns in the third layer of woven or laid glass fabric is 3 to 50 yarns / cm in their respective cases.

44. The die-cut part according to claim 43, Its features The warp yarn count is 5-10 / cm and / or the weft yarn count is 4-10 / cm.

45. The die-cut part according to any one of claims 1 to 10, Its features The third layer of woven or laid glass fabric has a thread weight of 500 to 1000 decibels in both the longitudinal and transverse directions.

46. ​​The die-cut part according to any one of claims 1 to 10, Its features The longitudinal fineness of the longitudinal thread and / or the transverse fineness of the transverse thread of the third layer of woven or laid glass fabric is greater than 2000 dentes / cm.

47. The die-cut part according to any one of claims 1 to 10, Its features In the weaving of glass fabrics, the threads are woven in a plain weave.

48. The die-cut part according to any one of claims 1 to 10, Its features The laid glass fabric is a sheet-like structure composed of one or more sheets of parallel-extending tension lines.

49. The die-cut part according to claim 48, Its features The glass fabric is a single-layer fabric.

50. The die-cut part according to any one of claims 1 to 10, Its features The pressure-sensitive adhesive in the form of a laminated adhesive in the second layer and / or the fourth layer is a dry polymer dispersion, wherein the polymer is composed of: (a) 95.0-100.0% by weight of n-butyl acrylate and / or 2-ethylhexyl acrylate (b) 0.0-5.0% by weight of olefinic unsaturated monomers having acid or anhydride functional groups.

51. The die-cut part according to claim 50, Its features The polymer is composed of 95.0-99.5% by weight of n-butyl acrylate and / or 2-ethylhexyl acrylate and 0.5-5% by weight of olefinic unsaturated monomers having acid or anhydride functional groups.

52. The die-cut part according to claim 50, Its features The composition of the polymer is as follows: (a) 95.0-100.0% by weight of n-butyl acrylate, and (b) 0.0-5.0% by weight of acrylic acid.

53. The die-cut part according to any one of claims 1 to 10, Its features The sixth layer is a single-layer or multi-layer tape with a foamed acrylate-based adhesive.

54. The die-cut part according to claim 53, Its features The tape has a soft phase, which comprises polymer foam, viscoelastic material and / or elastomeric material.

55. The die-cut part according to claim 54, Its features The soft phase includes a polymer foam, and the polymer foam includes partially or fully expanded microspheres.

56. The die-cut part according to claim 55, Its features The polymer foam comprises microspheres having a diameter of 3 µm-40 µm in its unexpanded state at 25°C, and / or having a diameter of 10 µm-200 µm after expansion.

57. The die-cut part according to claim 55, Its features The polymer foam contains up to 30% by weight of microspheres, based on the total mass of the polymer foam.

58. The die-cut part according to claim 55, Its features The polymer foam is characterized by having virtually no open cavities.

59. The die-cut part according to any one of claims 1 to 10, Its features All layers in the die-cut part have the same shape and size and are arranged equally.

60. The die-cut part according to any one of claims 1 to 10, Its features The dimensions of the die-cut parts are represented by discs with a diameter of 10-100 mm.

61. An opening having a die-cut part according to any one of the preceding claims.

62. The opening according to claim 61, wherein it is an opening in the vehicle body.

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