Composite sheet with functional membrane and current collector

Abstract

A composite sheet (1) with a functional membrane (4) includes at least a surrounding edge (K) of the composite sheet (1), a surrounding edge (U) of the functional membrane (4), at least one collector (5), an outer sheet (2) with an outer surface (I) and an inner space side surface (II), an inner sheet (6) with an outer surface (III) and an inner space side surface (IV), and a thermoplastic interlayer (3) connecting the inner space side surface (II) of the outer sheet (2) and the outer surface (III) of the inner sheet (6), wherein the functional membrane (4) is embedded in the thermoplastic interlayer (3), and the functional membrane (5) The surrounding edge (U) of 4) is recessed relative to the surrounding edge (K) of the composite sheet (1) in the direction of the center of the surface of the composite sheet (1). At least one collector (5) is arranged between the inner surface (II) of the outer sheet (2) and the outer surface (III) of the inner sheet (6) and extends between the surrounding edge (K) of the composite sheet (1) and the surrounding edge (U) of the functional membrane (4) in the edge region (R) of the composite sheet (1). The spacing x between the collector (5) and the surrounding edge (U) of the functional membrane (4) is between 5 mm and 50 mm.

Description

TECHNICAL FIELD

[0001] The present invention relates to a composite pane (Verbundscheibe) comprising a functional film (Funktionsfolie) and at least one current collector (Sammelleiter) and a method for producing such a composite pane. BACKGROUND

[0002] Modern motor vehicle glazing is increasingly equipped with additional functions, such as heatable layers, functional elements with electrically switchable optical properties and displays. Here, a plurality of these elements are often to be integrated in one pane.

[0003] In particular, windshields are often equipped with so-called head-up displays (HUD). With a projector, typically in the dashboard area, an image is projected onto the windshield, is reflected there and is perceived by the driver as a virtual image (from the perspective of the driver) behind the windshield. In this way, important information, such as the current driving speed, navigation or warning prompts, can be projected into the driver's field of view, which the driver can perceive without having to move his gaze from the roadway. In this way, head-up displays can significantly contribute to improving traffic safety.

[0004] DE 10 2014 220 189 A1 discloses a HUD projection assembly which operates with p-polarized radiation in order to generate a HUD image. Since the angle of incidence is typically close to the Brewster angle and the p-polarized radiation is therefore only reflected to a small extent by the glass surface, the windshield has a reflective structure which can reflect the p-polarized radiation in the direction of the driver. As a reflective structure a single metal layer with a thickness of 5 nm to 9 nm, for example composed of silver or aluminum, which is applied on the outer side of the inner pane facing away from the interior of the passenger vehicle, is suggested.

[0005] In US 2004 / 0135742 A1 likewise a HUD projection assembly is disclosed which operates with p-polarized radiation in order to generate a HUD image and has a reflective structure which can reflect the p-polarized radiation in the direction of the driver. As a reflective structure a multilayered polymer layer as disclosed in US 5,882,774 A is suggested.

[0006] DE 698 20 012 T2 discloses a method for laminating a composite pane comprising a polymer interlayer with an infrared-reflecting coating, wherein a layer portion of the polymer interlayer carrying the infrared-reflecting coating is removed in the edge region of the composite pane. Thereby, a corrosion of the coating from the pane edges is avoided.

[0007] Not only head-up displays but also other display applications or functional elements with electrically switchable optical properties are often used in the form of functional films. This has the advantage that the functional films can be easily introduced into the layer stack when laminating the composite sheet and can be prefabricated independently of the manufacture of the composite sheet. Here, the functional films are generally based on one or more polymer carrier films, on or between which functional layers are applied. These polymer carrier films are joined to the sheets of the composite sheet via the thermoplastic composite film when laminating. It must be noted here that complete degassing of the layer stack and complete removal of air inclusions between the carrier film and the composite film also takes place. Here, remaining air inclusions lead to product defects. If, in addition to the functional film to be integrated, further elements are installed which require current collectors for electrical contacting, complete degassing becomes further difficult. In addition to the problems described, increasing attention must be paid to air inclusions in the vicinity of the current collectors. SUMMARY

[0008] There is therefore a need for a composite sheet comprising a functional film and a current collector which does not have these disadvantages of the prior art. It is an object of the present invention to provide an improved composite sheet and a method for manufacturing said composite sheet.

[0009] According to the invention, the object is achieved by a composite sheet according to the invention. Preferred embodiments are known from the text.

[0010] The composite sheet according to the invention comprises an outer sheet and an inner sheet. The outer sheet has an outer side surface I and an inner space side surface II, while the inner sheet has an outer side surface III and an inner space side surface IV. The inner space side surface II of the outer sheet is connected to the outer side surface III of the inner sheet via a thermoplastic intermediate layer. A functional film is embedded in the thermoplastic intermediate layer of the composite sheet. The composite sheet comprises a surrounding edge. The functional film likewise comprises a surrounding edge, wherein the surrounding edge of the functional film is recessed in the direction of the face center of the composite sheet relative to the surrounding edge of the composite sheet. Here, the functional film is embedded in the thermoplastic intermediate layer. Furthermore, the composite sheet according to the invention comprises at least one current collector. The current collector is integrated in the composite sheet between the inner side surface II of the outer sheet and the outer side surface III of the inner sheet. Here, the current collector extends between the surrounding edge of the composite sheet and the surrounding edge of the functional film in the edge region of the composite sheet. According to the invention, the distance of the at least one current collector from the surrounding edge of the functional film is between 5 mm and 50 mm (measured along the current collector). The shortest distance between the current collector and the surrounding edge of the functional film is accordingly taken into account here.

[0011] The composite sheet according to the application makes possible the combination of a functional film with a current collector arranged close to the functional film in the edge region of the composite sheet without air pockets of the composite sheet and the defects that go with this. The inventors have found that a spacing according to the application of 5 mm to 50 mm between the functional film and the current collector is important for good lamination of the composite sheet. If the spacing is too small, the air between the surrounding edge of the functional film and the current collector has insufficient opportunity to escape. If the spacing is too large, the gap between the surrounding edge of the functional film and the current collector cannot be uniformly filled with the material of the thermoplastic composite film that melts during lamination and likewise defects are formed. In the range according to the application, in contrast, defect-free venting can be achieved.

[0012] Preferably, the spacing between at least one current collector relative to the surrounding edge of the functional film is 10 mm to 30 mm, particularly preferably 15 mm to 25 mm (measured as the respective shortest spacing along the current collector). Particularly uniform lamination can be found in these ranges.

[0013] The composite sheet is provided for separating an interior space from an exterior environment in a window opening, in particular a window opening of a vehicle. In the sense of the present application, the sheet of the composite sheet that faces the interior space, in particular the interior space of a vehicle, is denoted as inner sheet. The sheet that faces the exterior environment is denoted as outer sheet. The composite sheet is preferably a vehicle windshield (in particular a windshield of a motor vehicle, for example a passenger car or a heavy goods vehicle). The composite sheet can however also be a side window sheet or a roof sheet of a vehicle.

[0014] The composite sheet has an upper edge and a lower edge and two side edges that extend therebetween. An upper edge is denoted as such an edge that is provided for pointing upwards in the installed position. A lower edge is denoted as such an edge that is provided for pointing downwards in the installed position. The upper edge is often also referred to as roof edge and the lower edge as engine edge.

[0015] The outer sheet and the inner sheet each have an outer side surface and an interior space side surface and a surrounding side edge that extends therebetween. In the sense of the present application, an outer side surface is denoted as such a main face that is provided for facing the exterior environment in the installed position. In the sense of the present application, an interior space side surface is denoted as such a main face that is provided for facing the interior space in the installed position. The interior space side surface of the outer sheet and the outer side surface of the inner sheet face one another and are connected to one another by the thermoplastic intermediate layer.

[0016] A wide variety of monolayer or multilayer films known to the expert can be used as functional film. The present application is particularly suitable for integrating functional films with carrier film materials which show poor adhesion to glass as such. Due to the poor adhesion to glass, such carrier films are embedded between thermoplastic composite films, wherein the bubble-free venting design of such layer stacks is difficult, even without current collectors in the edge regions of the composite sheet. Preferably, the functional film comprises at least one carrier film based on polyethylene terephthalate (PET), polyethylene (PE), polymethyl methacrylate (PMMA), triacetyl cellulose (TAC) and / or polycarbonate and / or copolymers or mixtures thereof, particularly preferably a carrier film based on polyethylene terephthalate (PET). These materials are used as carrier film materials for functional films available on the market and show the described venting problems. Venting is further made difficult in the presence of current collectors in the edge regions. The present application provides a remedy here.

[0017] Known functional films applied in the automotive sector are for example HUD films, display films and functional films with electrically switchable optical properties. Functional films with electrically switchable optical properties comprise for example PDLC films, SPD films, electrochromic films or electroluminescent films. These functional films with electrically switchable optical properties are generally designed as multilayer films comprising one or more carrier films and an active layer arranged thereon or therebetween. As carrier film material PET is generally used. The active layer changes its optical properties upon application of a voltage.

[0018] In one possible design, the functional film is a PDLC film Polymer dispersed liquid Crystal i.e. a polymer dispersed liquid crystal. The active layer of a PDLC functional film comprises liquid crystals which are embedded in a polymer matrix. The active layer is arranged between two carrier films, wherein surface electrodes are present on the surfaces of the carrier films facing the active layer. If no voltage is applied to the surface electrodes, the liquid crystals are oriented disorderly, which leads to a strong scattering of light rays passing through the active layer. If a voltage is applied to the surface electrodes, the liquid crystals are oriented in a common direction and the transmittance of light rays through the active layer is increased. Such a PDLC functional film is for example known from DE 10 2008 026 339 Al.

[0019] In a further possible design, the functional film is an SPD, electrochromic or electroluminescent functional film.

[0020] SPD films Suspended particle deviceAn SPD (i.e. suspended particle device) comprises an active layer comprising suspended particles, wherein the absorption of light rays through the active layer can be changed by means of applying a voltage to the face electrode. The absorption change is based on the orientation of the rod-shaped particles in the electric field upon application of the voltage. SPD functional films are known, for example, from EP 0 876 608 B1 and WO 201 1033313 A1.

[0021] In electrochromic functional films, the active layer of the functional film is an electrochemical active layer. The transmission of visible light depends on the degree of intercalation of ions into the active layer, wherein the ions are provided, for example, by an ion storage layer between the active layer and the face electrode. This transmission can be influenced by a voltage applied to the face electrode, which causes the migration of the ions. Suitable functional layers comprise, for example, at least tungsten oxide or vanadium oxide. Electrochromic functional elements are known, for example, from WO 2012007334 A1, US 20120026573 A1, WO 201 0147494 A1 and EP 1 862 849 A1.

[0022] In the case of electroluminescent functional films, the active layer comprises an electroluminescent material, in particular an organic electroluminescent material, whose luminescence is excited by the application of a voltage. Electroluminescent functional films are known, for example, from US 2004227462 A1 and WO 201 01 12789 A2. Electroluminescent functional films can be used as simple light sources or can be displayed as a display with an arbitrary illustration.

[0023] A further functional film preferred in the scope of the present application is a display film comprising a diffusely reflective layer or a surface that diffusely reflects incident light rays. Here, diffuse reflection is understood conceptually as non-directional reflection. At the diffusely reflective layer, for example, an image of a projector is shown that is directed from the interior of the vehicle towards the inner pane of the vehicle glass, wherein the display film displays the real image in the plane of the laminated pane. Here, the real image is distinguished from a virtual image, wherein the virtual image is in a plane different from the projection plane, while the real image is displayed in the projection plane.

[0024] The display film comprises, for example, a diffusely reflecting inner space side surface with a diffusely reflecting coating. The diffusely reflecting coating preferably comprises nanoparticles or microparticles, for example silica particles, polymer particles or liquid crystals. Alternatively, metal or metal oxide particles can also be used for this purpose. In particular, the nanoparticles or microparticles mentioned have a spherical shape and / or are transparent or light-transmissive. In particular, display films with a diffusely reflecting coating comprising titanium dioxide particles (TiOx particles) or silver particles have proven to be advantageous. Likewise, display films with an organic diffusely reflecting coating (containing cholesteric liquid crystals) are very suitable for ensuring good image quality. In a particularly preferred embodiment, the display film comprises cholesteric liquid crystals oriented in a matrix. One possible example of a display film comprising randomly dispersed cholesteric liquid crystal droplets covered by an index matching layer is described in WO 2017 / 204103 A1. The cholesteric liquid crystal droplets are essentially hemispherical in shape, the radius thereof depending on the contact angle between the thin film and the droplet. Wavelength selectivity of the display film is likewise possible, as described, for example, in WO 2016 / 175183 A1.

[0025] When one surface of the display film comprises random nanostructures or microstructures, then the other surface of the display film is preferably smooth.

[0026] In another preferred embodiment, the display film comprises a structured plastic film, wherein the plastic film comprises a plurality of structured surfaces and the properties of the display film are determined via the slope of the contact surface between adjacent structured layers. Exemplary embodiments and methods for the construction of the layers of the display film are described in WO 2012 / 104547 A1. In comparison with particle-based display films, less haze and better luminance factor (also referred to as "screen gain") often have to be achieved in structured display films.

[0027] Preferably, the display film comprises as carrier material a film containing polyethylene (PE), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), triacetyl cellulose (TAC) and / or polycarbonate.

[0028] Suitable display films are available on the market in principle, wherein triacetyl cellulose, polymethyl methacrylate or polycarbonate are used as common carrier materials. These materials exhibit only very low adhesion to glass sheets and for this reason are embedded between thermoplastic composite films, wherein a bubble-free venting design of such layer stacks is difficult, even without current collectors in the edge region of the composite sheets.

[0029] It is particularly preferred that the functional film is a reflective film which can be used as a HUD film. The reflective film is metal-free and is suitable for reflecting at least 5 %, preferably 10 % to 50 %, particularly preferably 15 % to 30 %, in particular 20 % to 25 % of p-polarized light rays incident on the film. This is particularly advantageous in view of a good HUD image.

[0030] The reflective film preferably has a thickness of between 20 pm (micrometers) and 120 pm, particularly preferably between 30 pm and 90 pm, very particularly preferably between 50 pm and 75 pm.

[0031] The reflective film is preferably a polyethylene terephthalate (PET)-based film which is coated with a stack of PET- and / or polyethylene naphthalate (PEN)-based copolymer layers. The coating is preferably applied on the interior space-side surface, that is to say the surface facing the vehicle interior. Suitable reflective films are described, for example, in US No. 5,882,774 A.

[0032] There is a great need, especially in the described reflective films or diffuse reflective display films as HUD films, to integrate these functions at the same time with elements which require a voltage supply in a composite sheet. It is worth mentioning here, for example, a heatable composite sheet which has a HUD film or a diffuse reflective display film at the same time.

[0033] The at least one current collector of the composite sheet according to the application makes it possible to supply voltage to the electrical elements in the composite sheet, wherein the current collector makes it possible to combine the electrical elements with the functional film only in relation to the distance according to the application of the current collector from the functional film.

[0034] Preferably, the composite sheet comprises at least two current collectors. Here, the current collectors are preferably mounted at two oppositely situated sections of the surrounding edge of the composite sheet. In this way, voltage can be applied at oppositely situated sections of the electrical elements.

[0035] Preferably, the at least one current collector is mounted on the conductive layer in conductive contact with the conductive layer. Particularly preferably, the at least two current collectors are in conductive contact on the conductive layer, wherein the two current collectors are arranged in the edge region of the composite sheet at a distance of 5 mm to 50 mm from the surrounding edge of the functional film. The shortest distance between the current collector and the edge of the functional film which is closest to said current collector is considered accordingly here.

[0036] The conductive layer can be brought into the composite sheet by means of different techniques known to the expert. Preferably, the conductive layer is mounted on the carrier film or directly on the sheet of the composite sheet.

[0037] The electrically conductive layer is preferably mounted on the interior space side surface of the outer sheet or on the outer side surface of the inner sheet in a surface-like manner. Preferably, the electrically conductive layer is a heating layer. Here, the electrically conductive layer has at least two current collectors, which are preferably arranged at opposite sections of the encircling edge of the composite sheet. When a voltage is applied between the at least two current collectors, the electrically conductive layer is flowed through by an electric current and is heated in this case.

[0038] If the functional film according to the application is a reflective film or a diffuse reflective display film as a HUD film, the electrically conductive layer is preferably arranged on the interior space side surface of the outer sheet. This has the advantage that the electrically conductive layer does not influence the image projected onto the functional film.

[0039] Glasses with electrically conductive layers are known to the expert. In principle, every electrically conductive layer which can be electrically contacted by means of a current collector can be used in connection with the application.

[0040] The electrically conductive layer comprises at least one metal, metal alloy or transparent conductive oxide, preferably transparent conductive oxide, and has a thickness of 10 nm to 2 pm. The electrically conductive layer is preferably transparent. Transparent here means permeable to electromagnetic radiation, preferably electromagnetic radiation of a wavelength of 300 nm to 1,300 nm, and especially to visible light. Suitable electrically conductive layers are known, for example, from WO 03 / 024155, US 2007 / 0082219 A1, US 2007 / 0020465 A1, WO 2013 / 104438 or WO 2013 / 104439, DE 20 2008 017 611 U1, EP 0 847 965 B1 or WO 2012 / 052315 A1. The electrically conductive layer typically comprises one or more, for example two, three or four, electrically conductive functional monolayers. The functional monolayer preferably comprises at least one metal, for example silver, gold, copper, nickel and / or chromium, or a metal alloy. The functional monolayer particularly preferably comprises at least 90 percent by weight of metal, especially at least 99.9 percent by weight of metal. The functional monolayer can consist of a metal or a metal alloy. The functional monolayer particularly preferably comprises silver or a silver-containing alloy. Such a functional monolayer has particularly advantageous electrical conductivity, while at the same time having a relatively high transmittance in the spectral range of visible light. The thickness of the functional monolayer is preferably 5 nm to 50 nm, particularly preferably 8 nm to 25 nm. In this thickness range, an advantageously high transmittance in the spectral range of visible light and particularly advantageous electrical conductivity are achieved.

[0041] The current collector comprises an electrically conductive structure, preferably comprising silver, and has, for example, a thickness of 5 pm to 40 pm. The width of the current collector is preferably 0.5 mm to 30 mm, particularly preferably 1 mm to 20 mm. The current collector is preferably mounted at a distance of 0.5 mm to 20 cm from the closest section of the encircling edge of the composite sheet.

[0042] The current collector is provided for connection to an external voltage source, wherein, as a result of a potential difference, an electric current flows through the electrically conductive layer.

[0043] The mounting of the current collector can be achieved, inter alia, by laying, printing, soldering or pasting.

[0044] In a preferred embodiment, the current collector is configured as a printed and fired conductive structure. The printed current collector comprises at least one metal, preferably silver. The electrical conductivity is preferably achieved via metal particles, particularly preferably silver particles, contained in the current collector. The metal particles can be in an organic and / or inorganic matrix, for example a paste or an ink, preferably as a fired screen printing paste with frit. The layer thickness of the printed current collector is preferably 5 μιη to 40 μιη, particularly preferably 8 μιη to 20 μιη and very particularly preferably 10 μιη to 15 μιη. Printed current collectors with these thicknesses are technically easily achievable and have an advantageous current-carrying capacity.

[0045] In another preferred embodiment, the current collector is configured as a strip of an electrically conductive film. The current collector then comprises, for example, at least aluminum, copper, tinned copper, gold, silver, zinc, tungsten and / or tin or alloys thereof. The strip preferably has a thickness of 10 μιη to 500 μιη, particularly preferably 30 μιη to 300 μιη. Current collectors made of electrically conductive films with these thicknesses are technically easily achievable and have an advantageous current-carrying capacity. The strip can be electrically connected to the electrically conductive layer, for example via solder, via an electrically conductive adhesive or an electrically conductive adhesive tape, or by direct laying. In order to improve the electrically conductive connection, for example a silver-containing paste can be arranged between the electrically conductive layer and the current collector.

[0046] The thermoplastic intermediate layer preferably comprises at least a first thermoplastic composite film and a second thermoplastic composite film, between which the functional film is placed. The first thermoplastic composite film and the second thermoplastic composite film are arranged above and below the functional film and enclose the functional film. The first thermoplastic composite film connects the functional film with the outer sheet and the second composite film connects the functional film with the inner sheet.

[0047] The first thermoplastic composite film and the second thermoplastic composite film can each independently comprise at least polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), polyurethane (PU) or mixtures or copolymers or derivatives thereof, preferably polyvinyl butyral (PVB).

[0048] The first thermoplastic composite film and the second thermoplastic composite film can each be configured from a single film or from more than one film.

[0049] The first and the second thermoplastic composite film can be between 20 pm (micrometer) and 2 mm thick. The first and / or the second thermoplastic composite film can for example be 0.2 mm to 2 mm, particularly preferably 0.3 mm to 1 mm (for example 0.38 mm or 0.76 mm) thick. The thickness of the first thermoplastic composite film and the thickness of the second thermoplastic composite film are preferably constant over the entire length, so that the intermediate layer has a rectangular cross section. The composite film is thus not a wedge-shaped film. If the first or the second thermoplastic composite film is a functional composite film with acoustic damping properties, it is preferably 0.51 mm or 0.84 mm thick.

[0050] In a particularly preferred embodiment, the functional film is a reflective film or a diffuse reflective display film as HUD film, wherein the first thermoplastic composite film has a thickness of 200 pm to 1000 pm, preferably 300 pm to 850 pm, and the second thermoplastic composite film is between 10 pm and 120 pm, preferably between 15 pm and 90 pm, particularly preferably between 20 pm and 75 pm thick. In the use of the composite sheet as a head-up display or a diffuse display of a motor vehicle, generally a projector is installed in the dashboard area and the image is projected onto the inner space side surface of the inner sheet. Here, the second thermoplastic composite film is in the light path between the projector and the functional film. If the second thermoplastic composite film is implemented as thin as possible, this is advantageous in view of the image quality of the projected image.

[0051] Optionally, the first or the second thermoplastic composite film or not only the first but also the second thermoplastic composite film is a functional intermediate layer. Here, a "functional intermediate layer" means a composite film with at least one special function, in particular an acoustic function, a color function, a daylight function or a combination of these functions.

[0052] In one embodiment, only the first or only the second thermoplastic composite film is a functional intermediate layer. However, it is also possible that not only the first but also the second thermoplastic composite film is a functional intermediate layer, wherein these functional intermediate layers can have the same or preferably different functions.

[0053] In a particularly preferred embodiment, the first and / or the second thermoplastic composite film is a functional intermediate layer with acoustic damping properties. Such an acoustically damping composite film is typically composed of at least three layers, wherein the intermediate layer has a higher plasticity or elasticity than the outer layers surrounding it, for example due to a higher proportion of plasticizer.

[0054] It has proven to be particularly advantageous if the first thermoplastic composite film, which connects the composite film to the outer sheet, is implemented as an acoustically damping composite film. Thereby, advantageous acoustic properties of the composite sheet are derived.

[0055] The acoustic damping composite film is generally characterized via so-called mechanical impedance measurement (MIM). Here it is the standardized method which can be found in ISO 16940, according to which the damping can be calculated by measuring the natural frequency. According to the standard, the acoustic damping composite film to be examined is laminated between two glass sheets of a thickness of 2.1 mm in order to make possible a corresponding comparison in the case of different glass thicknesses. It is thus made possible for the expert to select a suitable interlayer in accordance with the well-known standardized measurement method.

[0056] The mechanical impedance measurement is carried out at the earliest one month after the composite glass has been produced. Furthermore, the acoustic damping composite film itself is laminated with two glass sheets of a thickness of 2.1 mm into a composite glass at the earliest one month after its production. Thereby it is ensured that at the time of the measurement a stable state has been built up.

[0057] In a preferred embodiment of the application, the acoustic damping composite film is used as the first composite film, in which it applies that the damping coefficients of the first mode η1 and of the second mode η2 of a composite glass sheet with a surface of 25 mm x 300 mm, which is composed of two glass sheets with a corresponding thickness of 2.1 mm between which the acoustic damping composite film is laminated, in the case of a mechanical impedance measurement (MIM) according to ISO 16940 at a temperature of 20°C are η1≥ 0.20 and η2≥ 0.25, preferably η1≥ 0.25 and η2≥ 0.30, particularly preferably η1≥ 0.25 and η2≥ 0.35.

[0058] Preferably, the functional film extends over at least 80% of the surface of the sheet. In particular, the functional film is arranged between the first thermoplastic interlayer and the second thermoplastic interlayer comprehensively (apart from a surrounding edge region), which as a communication window is to ensure the transmission of electromagnetic radiation through the composite sheet, so that the functional film is preferably not arranged there. In the region in which the current collector is provided, the spacing between the functional film and the current collector is carried out in accordance with the application. In the remaining region along the surrounding edge of the composite sheet, the functional film is preferably removed in the surrounding edge region. The surrounding edge region in which the functional film is preferably not arranged has a width of, for example, up to 20 cm, in particular 20 mm. It also prevents direct contact of the functional film with the surrounding atmosphere, so that the functional film within the composite sheet is protected from corrosion and damage.

[0059] In one embodiment, the functional film extends over the entire surface of the sheet (apart from the region of the current collector in which the spacing in accordance with the application applies).

[0060] The composite pane according to the application can additionally comprise a masking print (Abdeckdruck), which consists in particular of a dark, preferably black, enamel. The masking print is in particular a peripheral, that is to say frame-like, masking print. The peripheral masking print firstly serves as a UV protection for the assembly adhesive of the composite pane. The masking print can be configured non-transparently and completely. The masking print can also be configured at least section-wise semi-transparently, for example as a dot grid, a stripe grid or a check grid. Alternatively, the masking print can also have a gradient, for example from a non-transparent cover to a semi-transparent cover. In a preferred embodiment, the masking print is configured such that the side edges of the reflective film are covered by the masking print when viewed towards the composite pane. If the composite pane has a communication, sensor or camera window, the masking print is preferably enlarged in the direction of the pane centre to the communication, sensor or camera window, such that the cutting edges of the recess(es) around the communication, sensor or camera window are also covered by the masking print.

[0061] The masking print is usually applied on the interior space side surface of the outer pane or on the interior space side surface of the inner pane.

[0062] Preferably, the circumferential edges of the functional film are covered by the non-transparent masking print of the composite pane. Since the current collector of the composite pane is located between the circumferential edges of the functional film and the circumferential edges of the composite pane, it is likewise covered by the masking print. This results in a visually appealing concealment of the current collector and the edges of the functional film.

[0063] The outer pane and / or the inner pane can have an anti-reflection coating, an anti-adhesion coating, an anti-scratch coating, a photocatalytic coating, a solar protection coating and / or a low-emission coating.

[0064] The outer pane and the inner pane are preferably made of glass, in particular soda-lime glass, which is common for window panes. The panes can in principle however also be made of other glass types, for example borosilicate glass, quartz glass, aluminosilicate glass, or transparent plastics, for example polymethyl methacrylate or polycarbonate. The thickness of the outer pane and the inner pane can vary widely. Panes having a thickness in the range from 0.8 mm to 5 mm, preferably 1.4 mm to 2.5 mm, for example panes with a standard thickness of 1.6 mm or 2.1 mm, are preferably used. It is however also possible for the outer pane and / or the inner pane to have a thickness of 0.55 mm or 0.7 mm.

[0065] The outer pane and the inner pane can independently of one another be transparent and colourless, however also coloured or coloured. In a preferred design, the total transmittance through the composite pane is greater than 70%. The concept of "total transmittance" relates to the method for testing the light transmission of motor vehicle panes determined by ECE-R 43, appendix 3, section 9.1.

[0066] The outer and inner sheets may be independently unstressed, partially prestressed, or prestressed. If at least one of the sheets has prestress, the prestress may be thermal or chemical.

[0067] The composite sheet according to the invention is preferably bent in one or more directions in space, as is common for automotive sheets, wherein the typical radius of curvature is in the range of about 10 cm to about 40 m. However, the composite sheet according to the invention can also be planar, for example, when it is provided as a sheet for buses, trains, or tractors.

[0068] In one possible implementation, the first thermoplastic composite film and / or the second thermoplastic composite film are functional interlayers with color functionality. This means that the interlayer is colored or tinted. Here, the interlayer can be fully tinted or colored. Alternatively, the interlayer can also have color gradients or colored patterns. In composite sheets used as windshields, the tinting or coloring is configured such that the composite sheet has a light transmittance greater than 70% in the spectral range of 380 nm to 780 nm. In composite sheets used as roof sheets or rear side window sheets, the tinting or coloring can also be configured more deeply, and the composite sheet can therefore have a light transmittance of 70% or less in the spectral range of 380 nm to 780 nm.

[0069] The first thermoplastic composite film and / or the second thermoplastic composite film may also be a functional intermediate layer in which two or more functional properties are combined, such as acoustic damping properties with color function and / or sunlight function.

[0070] A particularly preferred design of the composite sheet according to the invention preferably includes a functional film, which is a reflective film or a diffuse reflection display film serving as a HUD film, preferably a reflective film serving as a HUD film. The composite sheet has at least two current collectors electrically contacting the conductive layer, and said at least two current collectors are correspondingly mounted along the surrounding edges of the composite sheet at a spacing relative to the functional film according to the invention. The conductive layer is coated on the inner space side surface of the outer sheet and is preferably provided as a heating layer. The current collectors are arranged along opposing sections along the surrounding edges of the composite sheet.

[0071] This preferred design of the composite sheet according to the invention, with a functional film serving as a HUD film, can be equipped with a projector, thereby obtaining a projection assembly for a head-up display (HUD). Such a projection assembly is particularly used in motor vehicles, where the composite sheet is preferably a windshield. As is common in HUDs, the projector illuminates an area of ​​the windshield, where radiation is reflected in the direction of the observer (driver), thereby producing a virtual image perceived by the observer behind the windshield. The area of ​​the windshield that can be illuminated by the projector is called the HUD area. The radiation direction of the projector can typically be changed (especially vertically) by a mirror to adapt the projection to the observer's height. The area where the observer's eyes must be positioned in a given mirror orientation is called the eyebox fenster. This eyebox fenster can be vertically moved by adjusting the mirror, where the entire area thus accessible (i.e., the superposition of all possible eyebox fensters) is called the eyebox. An observer within the eyebox fenster can perceive the virtual image. Therefore, it naturally means that the observer's eyes must be within the eye movement range, rather than, for example, the entire body.

[0072] The terminology used in the HUD field is generally known to professionals. For a detailed explanation, please refer to Alexander Neumann's paper "Simulation-based Measurement Techniques for Testing Head-Up Displays" (Munich: University Library of the Technical University of Munich, 2012), especially Chapter 2, "Head-Up Displays," from the Institute of Computer Science at the Technical University of Munich.

[0073] The proportion of p-polarized radiation in the total radiation of the projector is preferably at least 70%. In an advantageous embodiment of the projection assembly for a head-up display, the proportion of p-polarized radiation in the total radiation of the projector is at least 80%; particularly preferably, the proportion of p-polarized radiation in the total radiation of the projector is 80% or 100%, and very particularly preferably 100%.

[0074] Here, the description of polarization direction refers to the plane of incidence of radiation on the composite sheet. p-polarized radiation is used to represent radiation whose electric field oscillates in the plane of incidence. s-polarized radiation is used to represent radiation whose electric field oscillates perpendicular to the plane of incidence. The plane of incidence is derived from the incident vector and the surface normal of the composite sheet at the geometric center of the HUD region.

[0075] The projector's radiation is preferably incident on the composite sheet at an angle of incidence of 50° to 80°, particularly 60° to 70°, typically, for example, 65°, as is common in HUD projection assemblies. The angle of incidence is the angle between the incident vector of the projected radiation and the surface normal at the geometric center of the HUD area. Because the typical incident angle of approximately 65° for HUD projection assemblies is relatively close to the Brewster angle used for air-glass transitions (57.2°, soda-lime glass), the p-polarized radiation component of the radiation emitted by the projector is hardly reflected by the sheet surface. However, the reflective film included in the composite sheet is optimized for the reflection of p-polarized radiation. In this way, the image perceived by the observer is not distorted, or is only distorted to a very small degree, by ghosting. Therefore, a wedge-shaped intermediate layer can be omitted.

[0076] In one embodiment of the projection assembly, 10% to 50%, preferably 15% to 30%, and particularly preferably 20% to 25% of the p-polarized light emitted by the projector and incident on the reflective film of the composite sheet is reflected by the reflective film in the direction of the observer.

[0077] Furthermore, the present invention relates to a method for manufacturing a composite sheet according to the present invention, comprising at least the following steps:

[0078] a) Provide inner or outer sheet materials.

[0079] b) Install at least one collector.

[0080] c) Laying a thermoplastic interlayer with a functional film, and

[0081] d) Lay out the outer or inner sheet to allow for the stacking of the sealing layers, and laminate them into a composite sheet.

[0082] The functional membrane is truncated before or during step c), and the surrounding edges of the functional membrane have a spacing of 5 mm to 50 mm relative to at least one current collector after truncation.

[0083] Preferably, before or during step a), a conductive layer is coated on the inner surface of the outer sheet or the outer surface of the inner sheet, and at least one current collector is conductively coated on the conductive layer. The conductive layer is coated using methods known to those skilled in the art. Preferably, the conductive layer is coated onto the sheet surface by physical vapor deposition (PVD), particularly preferably by cathodic sputtering (“sputtering”), and very particularly preferably by magnetic field-assisted cathodic sputtering (“magnetron sputtering”). The conductive layer is coated prior to the lamination of the composite sheet. Instead of coating the sheet surface, the coating can also, in principle, be provided on a carrier film.

[0084] The thermoplastic interlayer with the functional film is laid in step c) in one or more steps. Preferably, the thermoplastic interlayer comprises at least a first thermoplastic composite film and a second thermoplastic composite film, with the functional film placed between them. The functional film may be placed between the thermoplastic composite films before the interlayer is laid in step c). In this case, the thermoplastic interlayer with the functional film is laid as three layers in one step. Alternatively, the thermoplastic composite film and the functional film may also be laid separately in step c), wherein the interlayer with the embedded functional film is obtained directly in step c).

[0085] The shortening of the functional membrane before or during step c) can be achieved by means of professionally common methods (such as laser cutting) or by means of cutting with a blade.

[0086] Preferably, the venting structure is pressed into at least one collector during or after step b) and before step d). This venting structure further facilitates the venting of the stacked layers. The venting structure can be introduced into at least one collector, for example, by means of a structured roller, a toothed rolling tool, or a similar tool.

[0087] The composite sheet according to the invention can be laminated in step d) by methods known per se. The outer sheet, the inner sheet, and the functional film therebetween are laminated to each other via a thermoplastic composite film, for example by autoclave method, vacuum bag method, vacuum ring method, calendering method, vacuum laminator, or a combination thereof. Here, the connection between the outer sheet and the inner sheet is generally achieved under the action of heat, vacuum, and / or pressure.

[0088] If the composite sheet is curved, the outer and inner sheets preferably undergo a bending process before lamination. Preferably, the outer and inner sheets are bent together (i.e., simultaneously and using the same tools) in a completely uniform manner, because the shape of the sheets is thus optimally coordinated with each other for the subsequent lamination. Typical temperatures for the sheet bending process are, for example, 500ºC to 700ºC.

[0089] The implementation schemes for the method described above are equally applicable to the composite sheets according to the present invention and vice versa.

[0090] The present invention also includes the use of the composite sheet constructed according to the invention as a windshield in motor vehicles, preferably passenger cars, wherein the composite sheet serves as a projection surface for a projection assembly of a head-up display. The composite sheet constructed according to the invention can also be used as a side window sheet or roof sheet in motor vehicles, preferably passenger cars. In these cases, the composite sheet can also serve as a projection surface for a projection assembly of a head-up display. The preferred designs described above are accordingly applicable to this use. Attached Figure Description

[0091] The invention will now be further described with reference to the accompanying drawings and embodiments. The drawings are schematic illustrations and not to scale. The drawings are in no way limiting of the invention.

[0092] in:

[0093] Figure 1 The image shows a top view of the composite sheet according to the invention as a head-up display with a HUD area.

[0094] Figure 2 It shows the passage along the section line AA'. Figure 1 The cross-section of the composite sheet Figure 1 Projection components made of composite sheet materials,

[0095] Figure 3 The detailed layer structure with thermoplastic intermediate layer 3 is shown. Figure 1 Composite sheet,

[0096] Figure 4 An embodiment of the method according to the present invention is shown. Detailed Implementation Plan

[0097] Figure 1 A top view shows a composite sheet 1 according to the invention, serving as a windshield, particularly for a passenger vehicle. The composite sheet 1 is constructed from an outer sheet 2 and an inner sheet 6 connected to each other via a thermoplastic interlayer 3. A functional film 4 is embedded in the thermoplastic interlayer 3. The functional film 4 is a reflective film serving as a HUD film. The composite sheet has a HUD area B, in which an image can be projected onto the windshield by means of a projector. The surrounding edge K of the composite sheet 1 is divided into a lower edge U, an upper edge O, and two opposing side edges S, which connect the upper edge O and the lower edge U to each other. The lower edge U of the composite sheet 1 is arranged downwards along the direction of the passenger vehicle's engine, and the upper edge O of the composite sheet is arranged upwards along the direction of the vehicle roof. The side edges S extend along the A-pillars in the installed state of the composite sheet 1 in the motor vehicle. The outer sheet 2 faces the external environment in the installed position, and the inner sheet 6 faces the vehicle's interior space. Current collectors 5 extend correspondingly along the upper edge O and the lower edge U. The current collectors 5 contact the conductive layer 7. The conductive layer 7 is a heating layer. A reflective film 4 is placed in the composite sheet 1 such that the reflective film 4 reflects, for example, 20% to 25% of the p-polarized light incident on the film. The functional film 4 has a surrounding edge U, which is recessed in the direction of the center of the surface of the composite sheet 1 compared to the surrounding edge K of the composite sheet 1. The spacing x between the surrounding edge U of the functional film 4 and the current collector 5 of the corresponding edge segment adjacent to edge U is correspondingly 20 mm along the entire current collector 5. The composite sheet 1 is never cavitated, and in particular, cavitation or defects are never found in the area of ​​the current collector 5.

[0098] Figure 2 Showing the use of including Figure 1 The projection component of the HUD of the composite sheet 1, wherein the projection component is displayed as along the path according to Figure 1 The composite sheet has a cross-section along line A-A'. Furthermore, the projection assembly includes a projector 12, which faces the area of ​​the composite sheet 1. In this area, commonly referred to as the HUD area B, an image is generated by the projector 12, which is perceived as a virtual image by an observer 11 (vehicle driver) on the side of the composite sheet 1 opposite to it, when the observer's eyes are within the so-called eye-tracking range E. The radiation from the projector 12 is p-polarized, particularly approximately purely p-polarized. Because the projector 12 illuminates the windshield 1 at an incident angle of approximately 65º, close to the Brewster angle, the radiation from the projector is only negligibly reflected on the outer surfaces I, IV of the composite sheet 1. Conversely, the reflective film 4, serving as the functional film, is optimized for reflecting p-polarized radiation. It acts as a reflective surface for the radiation from the projector 12 used to generate the HUD projection.

[0099] Figure 3 The detailed layer structure with thermoplastic intermediate layer 3 is shown. Figure 1The composite sheet 1 consists of an outer sheet 2 and an inner sheet 6, for example, made of soda-lime glass. The outer sheet 2 has an outer surface I (also referred to as the outer side of the outer sheet) facing the external environment in the mounting position, and an inner space side surface II (also referred to as the inner side of the outer sheet) facing the internal space in the mounting position. Similarly, the inner sheet 6 has an outer surface III (also referred to as the inner side of the inner sheet) facing the external environment in the mounting position, and an inner space side surface IV (also referred to as the outer side of the inner sheet) facing the internal space in the mounting position. The outer sheet 2 has a thickness of, for example, 2.1 mm, and the inner sheet 6 has a thickness of 1.6 mm. A conductive layer 7 in the form of a heating layer is sputtered onto the inner space side surface II of the outer sheet 2. A current collector 5 is electrically in contact with the conductive layer 7, wherein the composite sheet 1 can be heated by applying a voltage at the current collector 5. The first thermoplastic composite film 3a is constructed from a single layer of thermoplastic material, such as a PVB film with a thickness of 0.76 mm or a PVB film with acoustic damping properties with a thickness of 0.81 mm. The second thermoplastic composite film 3b is constructed from a PVB film with a thickness of 0.38 mm. The functional film 4 is a reflective film disposed between the first thermoplastic composite film 3a and the second thermoplastic composite film 3b. The first thermoplastic composite film 3a and the second thermoplastic composite film 3b are fused together to form a thermoplastic interlayer 3 and surround the functional film 4 embedded therein. The reflective film 4 is metal-free and suitable for reflecting at least 5%, for example 20% to 25%, of p-polarized light incident on the film 4. The reflective film 4 is, for example, 50 μm to 75 μm thick and is, for example, a PET-based film coated with a PET and PEN-based copolymer layer stack. The reflective film 4 is disposed entirely between the first thermoplastic interlayer 3 and the second thermoplastic interlayer 5 (except for the surrounding edge region R). In the region of current collector 5, the spacing between the nearest segment of current collector 5 and the surrounding edge U of functional membrane 4 is correspondingly 20 mm. In the remaining surrounding edge region R, no reflective membrane 4 is arranged in the 20 mm wide area with the surrounding edge K of the composite sheet 1. The composite sheet 1 has an opaque masking print (not shown) that adheres to the surrounding edge U and current collector 5.

[0100] Figure 4 An embodiment of the method according to the present invention is shown, comprising at least the following steps:

[0101] I provides an inner sheet 6 or an outer sheet 2, wherein a conductive layer 7 is mounted on the inner space side surface II of the outer sheet 2 or the outer surface III of the inner sheet 6.

[0102] II. At least one current collector 5 is mounted on the conductive layer 7, wherein the at least one current collector 5 is in conductive contact with the conductive layer 7.

[0103] III. The first thermoplastic composite film 3a is laid onto the inner space side surface II of the outer sheet 2, or the second thermoplastic composite film 3b is laid onto the outer surface III of the inner sheet 6.

[0104] IV. A functional membrane 4 is laid, wherein the surrounding edges U of the functional membrane 4 have a spacing of 5mm to 50mm relative to the nearest current collector 5.

[0105] V. Lay the second thermoplastic composite film 3b or lay the first thermoplastic composite film 3a.

[0106] VI utilizes outer sheet 2 or inner sheet 6 to enclose the layers and laminates them into composite sheet 1.

[0107] Steps III through V may be performed in one or more steps. The truncation of functional membrane 4 may be performed before or during steps III through V.

[0108] List of reference numerals in the attached diagram:

[0109] 1. Composite sheet

[0110] 2 outer sheets

[0111] 3. Thermoplastic interlayer

[0112] 3a First thermoplastic composite film

[0113] 3b Second thermoplastic composite film

[0114] 4. Functional membranes

[0115] 5 collectors

[0116] 6 inner sheets

[0117] 7. Conductive layer

[0118] 10 projection components

[0119] 11. Observers, vehicle drivers

[0120] 12 Projectors

[0121] The surrounding edges of K composite sheet 1

[0122] The surrounding edge of the U-functional membrane 4

[0123] x is the spacing between the surrounding edge U of the functional membrane 4 and the current collector 5.

[0124] The edge area surrounded by R

[0125] B. HUD area of ​​composite sheet 1

[0126] E Eye movement range

[0127] The upper edge of composite sheet 1

[0128] The lower edge of U-composite sheet 1

[0129] Side edges of S composite sheet 1

[0130] (I) The outer surface of the outer sheet 2, facing away from the intermediate layer 3

[0131] (II) The surface of the outer sheet 2 facing the intermediate layer 3 on the inner space side.

[0132] (III) The outer surface of the inner sheet 6 facing the intermediate layer 3

[0133] (IV) The surface of the inner sheet 6 on the inner space side, facing away from the intermediate layer 3.

Claims

1. A composite sheet (1) with a functional film (4), comprising at least a surrounding edge (K) of the composite sheet (1), a surrounding edge (U) of the functional film (4), at least one current collector (5), an outer sheet (2) with an outer side surface (I) and an inner space side surface (II), an inner sheet (6) with an outer side surface (III) and an inner space side surface (IV), and a thermoplastic intermediate layer (3) connecting the inner space side surface (II) of the outer sheet (2) with the outer side surface (III) of the inner sheet (6), wherein - the functional film (4) is embedded in the thermoplastic intermediate layer (3), - the surrounding edge (U) of the functional film (4) is recessed in the direction of the face center of the composite sheet (1) relative to the surrounding edge (K) of the composite sheet (1), - the at least one current collector (5) is arranged between the inner space side surface (II) of the outer sheet (2) and the outer side surface (III) of the inner sheet (6) and extends in the edge region (R) of the composite sheet (1) between the surrounding edge (K) of the composite sheet (1) and the surrounding edge (U) of the functional film (4), and - the distance x between the at least one current collector (5) and the surrounding edge (U) of the functional film (4) is between 5 mm and 50 mm.

2. The composite sheet (1) according to claim 1, wherein The distance between the at least one current collector (5) and the surrounding edge (U) of the functional film (4) is 10 mm to 30 mm.

3. The composite sheet (1) according to claim 2, wherein The distance between the at least one current collector (5) and the surrounding edge (U) of the functional film (4) is 15 mm to 25 mm.

4. The composite sheet (1) according to any one of claims 1 to 3, wherein, The functional film (4) comprises at least one carrier film selected from the group consisting of polyethylene terephthalate (PET), polyethylene (PE), polymethyl methacrylate (PMMA), triacetyl cellulose (TAC), polycarbonate, and copolymers and mixtures of at least two thereof.

5. The composite sheet (1) according to claim 4, wherein The functional film (4) comprises a carrier film based on polyethylene terephthalate (PET).

6. The composite sheet (1) according to any one of claims 1 to 3, wherein The functional film (4) is a reflective film, which is metal-free and suitable for reflecting at least 5% of p-polarized light rays incident on the film.

7. The composite sheet (1) according to claim 6, wherein The reflective film is suitable for reflecting 10% to 50% of p-polarized light rays incident on the film.

8. The composite sheet (1) according to claim 6, wherein The reflective film is suitable for reflecting 15% to 30% of p-polarized light rays incident on the film.

9. The composite sheet (1) according to claim 6, wherein The reflective film is suitable for reflecting 20% to 25% of p-polarized light rays incident on the film.

10. The composite sheet (1) according to claim 6, wherein The reflective film as functional film (4) is between 20 pm (micrometer) and 120 pm thick.

11. The composite sheet (1) according to claim 10, wherein The reflective film as functional film (4) is between 30 pm and 90 pm thick.

12. The composite sheet (1) according to claim 10, wherein The reflective film as functional film (4) is between 50 pm and 75 pm thick.

13. The composite sheet (1) according to claim 6, wherein The reflective film as functional film (4) is a polyethylene terephthalate (PET)-based film, which is coated with a stack of copolymer layers based on PET and / or polyethylene naphthalate (PEN).

14. The composite sheet (1) according to any one of claims 1 to 3, wherein, The at least one current collector (5) is mounted on and electrically contacts an electrically conductive layer (7).

15. The composite sheet (1) according to claim 14, wherein The electrically conductive layer (7) is mounted on the inner space side surface (II) of the outer sheet (2) or on the outer side surface (III) of the inner sheet (6) in a planar manner.

16. The composite sheet (1) according to any one of claims 1 to 3, wherein The thermoplastic intermediate layer (3) comprises at least a first thermoplastic composite film (3.1) and a second thermoplastic composite film (3.2) between which the functional film (4) is interposed.

17. The composite sheet of claim 16, wherein, The first thermoplastic composite film (3.1) has a thickness of 200 pm to 1000 pm, while the second thermoplastic composite film (3.2) is between 10 pm and 120 pm thick.

18. The composite sheet of claim 17, wherein, The first thermoplastic composite film (3.1) has a thickness of 300 pm to 850 pm.

19. The composite sheet of claim 17, wherein, The second thermoplastic composite film (3.2) is between 15 pm and 90 pm thick.

20. The composite sheet of claim 17, wherein, The second thermoplastic composite film (3.2) is between 20 pm and 75 pm thick.

21. The composite sheet of claim 16, wherein, The first thermoplastic composite film (3.1) is a film with acoustic damping properties, an intermediate layer that absorbs infrared radiation, a colored intermediate layer or a combination thereof.

22. A method for producing a composite sheet (1) according to any one of claims 1 to 21, wherein, a) an inner sheet (6) or an outer sheet (2) is provided, b) the at least one current collector (5) is mounted, c) a thermoplastic intermediate layer (3) with a functional film (4) is laid down, and d) the layer stack is closed with an outer sheet (2) or an inner sheet (6) and is laminated to a composite sheet (1), wherein the truncation of the functional film (4) is carried out before or during step c) and the encircling edge (U) of the functional film (4) has a spacing of 5 mm to 50 mm relative to the current collector (5) after truncation.

23. The method of claim 22, wherein, An electrically conductive layer (7) is applied on the inner space side surface (II) of the outer sheet (2) or on the outer side surface (III) of the inner sheet (6) before or during step a) and the at least one current collector (5) is applied electrically conductively on the electrically conductive layer (7).

24. The method of claim 22 or 23, wherein, A ventilation structure is pressed into the at least one current collector (5) during or after step b) and before step d).

25. Use of the composite sheet (1) according to any one of claims 1 to 21 in a motor vehicle.

26. Use of the composite sheet (1) according to claim 25, wherein The motor vehicle is a passenger car.

27. Use of the composite sheet (1) according to claim 25, wherein The composite sheet (1) is used as a windshield. The composite sheet (1) is used as a windshield.

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