Composite pane with a reflective layer applied in regions

Abstract

The present invention relates to a composite pane (100), at least comprising an outer pane (1), a thermoplastic intermediate layer (3), an inner pane (2), at least one masking layer (4) arranged in a region of the composite pane (100), an adhesive layer (5) and a glass pane (6) with an external-side surface (V) and an internal-side surface (VI) and a thickness of 20 µm to 500 µm. The thermoplastic intermediate layer (3) is arranged between the outer pane (1) and the inner pane (2), the adhesive layer (5) is arranged between the inner pane (2) and the glass pane (6), at least one reflective layer (7) for reflecting light is arranged on the external-side surface (V) of the glass pane (6) and / or on the internal-side surface (VI) of the glass pane (6), and the glass pane (6) is arranged in a region of the composite pane (100) that lies entirely in the region in which the masking layer (4) is arranged when viewed perpendicularly through the composite pane (100). The reflective layer contains or consists of a dielectric layer, a silicon-based layer or a carbide layer.

Description

[0001] Composite pane with partially applied reflective layer

[0002] The invention relates to a composite pane with a reflective layer applied in some areas, a method for its production and its use, as well as a projection arrangement.

[0003] Modern automobiles are increasingly being equipped with so-called head-up displays (HIDs). Using a projector, typically located in the dashboard, images are projected onto the windshield, reflected there, and perceived by the driver as a virtual image behind the windshield. This allows important information to be projected into the driver's field of vision, such as the current speed, navigation information, or warnings, which the driver can perceive without having to take their eyes off the road. Head-up displays can thus significantly contribute to improving road safety.

[0004] However, head-up displays often have the problem that the area of ​​the windshield intended to reflect the light projected by the projector must have a high transparency of at least 70%. The reflected light from the projector is therefore overlaid by light from the outside environment, which, depending on the lighting conditions, can lead to a reduction in the contrast of the virtual image and thus to poorer visual perception for the driver. Adequate visual perception of safety-relevant information, such as lane departure warnings, speedometer, or engine speed, must be ensured in all weather and lighting conditions.It would be desirable to have a projection system based on head-up display technology that eliminates unwanted side images and is relatively easy to set up, while maintaining good visibility and sufficient brightness and contrast of the displayed image information. To achieve this, it is necessary to increase the contrast in the reflective area of ​​the windshield. The contrast increase can be achieved, for example, by making the background of the reflective area largely or completely opaque. However, such solutions require a reflective coating to be applied only in a locally limited area of ​​the windshield.

[0005] The application of metallic coatings to glass panes is usually achieved by sputtering, particularly magnetron sputtering. During sputtering, atoms are released from a target by bombardment with ions. Using physical vapor deposition, the glass pane is coated with the atoms released from the target in an evacuated chamber. Guided by electric fields, the atoms move through the chamber toward the glass pane. They move from the cathode, on which the target is arranged, to the anode. Due to the arrangement of the glass pane between the cathode and anode, the layer forms on the glass pane. In the case of magnetron sputtering, an additional magnetic field is arranged behind the cathode, which leads to faster layer growth and a denser, i.e., less porous, layer.Methods in which sputtering is used to coat glass panes are known, for example, from W09900528 A1, DE10126868 C1 and WO2017198363 A1.

[0006] Magnetron sputtering is also suitable for coating glass panes because, unlike many other coating technologies, it can be used even when the glass pane is curved, as is the case with panes intended for the automotive sector, for example. A disadvantage of sputtering, however, is that without special precautions, it cannot be used to selectively coat only certain surface areas, but always the entire surface. Selective coating of only certain surface areas can be achieved, for example, by complex masking of the areas that are not to be coated. However, such masking can only be integrated into the industrial series production of coated glass panes with considerable effort and is associated with relatively high costs.

[0007] Cold gas spraying is also a suitable method for coating glass panes and is a coating process generally known to those skilled in the art. It involves applying a powder to a substrate at very high speed. Methods for coating using cold gas spraying are known, for example, from WO2010 / 003396 A1, EP3845685 A1, and EP2902530 A1.

[0008] WO2022161894 A1 discloses a composite pane with a holographic optical element applied to the interior surface of the inner pane as a light-directing device for directing light from a projector. The light-directing device is arranged in overlap with a masking strip to enable high contrast. The present invention is based on the object of providing an improved composite pane with a reflective layer applied in certain regions. In particular, the composite pane should be easy to manufacture.

[0009] The object of the present invention is achieved by a composite pane according to claim 1. Preferred embodiments are evident from the subclaims.

[0010] The composite pane according to the invention comprises an outer pane, a thermoplastic intermediate layer, at least one masking layer, an inner pane, an adhesive layer, and a glass pane. The thermoplastic intermediate layer is arranged between the outer pane and the inner pane, and the adhesive layer is arranged between the inner pane and the glass pane. According to the invention, the at least one masking layer is arranged in a region of the composite pane, and the glass pane is arranged in a region of the composite pane that, when viewed perpendicularly through the composite pane, lies entirely within the region in which the at least one masking layer is arranged.

[0011] The composite pane is designed to separate the interior of a vehicle's window opening from the exterior. For the purposes of the invention, the "inner pane" refers to the pane of the composite pane facing the vehicle interior. The "outer pane" refers to the pane facing the exterior.

[0012] The laminated glass has, in particular, an upper edge and a lower edge, as well as two side edges running between them. The upper edge refers to the edge that is intended to face upwards in the installed position. The lower edge refers to the edge that is intended to face downwards in the installed position. In the case of a windshield, the upper edge is often referred to as the roof edge, and the lower edge as the engine edge.

[0013] The outer pane, the inner pane, and the glass pane each have an outer surface and an inner surface, and a circumferential side edge running between them. For the purposes of the invention, the "outer surface" refers to the main surface intended to face the outside environment in the installed position. For the purposes of the invention, the "interior surface" refers to the main surface intended to face the interior in the installed position. The interior surface of the outer pane and the outer surface of the inner pane face each other and are connected by the thermoplastic intermediate layer.

[0014] The outside surface of the outer pane is called Side I. The inside surface of the outer pane is called Side II. The outside surface of the inner pane is called Side III. The inside surface of the inner pane is called Side IV. The outside surface of the glass pane is called Side V. The inside surface of the glass pane is called Side VI.

[0015] The interior-side surface of the outer pane and the exterior-side surface of the inner pane face each other. In one embodiment, the inner pane is arranged between the outer pane and the glass pane, with the interior-side surface of the inner pane and the exterior-side surface of the glass pane facing each other. In a further embodiment, the glass pane is arranged between the outer pane and the inner pane, with the interior-side surface of the glass pane and the exterior-side surface of the inner pane facing each other.

[0016] According to the invention, the glass pane is very thin, with a thickness of 20 pm (micrometers) to 500 pm. The glass pane is thus made of ultra-thin glass. Such a pane of ultra-thin glass is flexible and can be advantageously adapted to the curvature of a pane.

[0017] In addition, according to the invention, at least one reflective layer for reflecting light is arranged on the outside surface of the glass pane and / or on the inside surface of the glass pane. Thus, a single reflective layer can be provided, which is arranged on the outside surface of the glass pane or on the inside surface of the glass pane. Alternatively, two reflective layers can be provided, which are arranged on the outside surface of the glass pane and on the inside surface of the glass pane. The outside surface and / or the inside surface of the glass pane is advantageously coated with the reflective layer, i.e. the reflective layer is arranged as a coating on the outside surface and / or the inside surface of the glass pane.

[0018] According to the invention, when the composite pane is installed in a vehicle, the at least one reflective layer is located at a shorter distance from the vehicle interior than at least one masking layer, so that the imaging unit of a projection arrangement arranged in the vehicle interior has a direct view of the reflective layer and the reflective layer can reflect light emitted by the imaging unit. It is also possible for an additional masking layer to be located closer to the vehicle interior than the reflective layer. In order to ensure a direct view of the reflective layer by the imaging unit in this case, this additional masking layer has one or more openings, so that the light from the imaging unit is reflected by the reflective layer and can be seen by a viewer in the vehicle interior.

[0019] Because the glass pane is arranged in a region of the composite pane which, when viewed perpendicularly through the composite pane, lies entirely in the region in which at least one masking layer is arranged, the reflective layer applied to the glass pane is also arranged in a region which, when viewed perpendicularly through the composite pane, lies entirely in the region in which the masking layer is arranged. Thus, when viewed perpendicularly through the composite pane or in orthogonal projection through the composite pane, the reflective layer is arranged in registration or overlap with the masking layer. The reflective layer therefore has no section which does not overlap with the masking layer, i.e. the reflective layer is only formed where it is located in front of the masking layer when viewed on the inside of the composite pane.This ensures high contrast and brightness and thus good recognizability of the virtual image reflected by the reflective layer.

[0020] In a preferred embodiment of the composite pane according to the invention, the glass pane has a thickness of 50 pm to 300 pm, preferably 50 pm to 100 pm, for example 70 pm.

[0021] As described above, the reflective layer is a reflective layer for reflecting light. The reflective layer is preferably opaque or partially translucent, which in the sense of the invention means that it has an average transmission (according to ISO 9050:2003) in the visible spectral range of preferably at most 80%, particularly preferably at most 50%, and in particular less than 10%. The reflective layer preferably reflects at least 10%, particularly preferably at least 50%, very particularly preferably at least 80%, and in particular at least 90% of the light incident on the reflective layer. The reflective layer preferably reflects p-polarized and s-polarized light in equal proportions, but it can also reflect p-polarized light and s-polarized light to different degrees.In one embodiment, the light reflected by the reflective layer comprises predominantly p-polarized light, so that the virtual image is clearly visible even when using s-polarizing sunglasses.

[0022] The light reflected by the reflective layer is preferably visible light, i.e. light in a wavelength range of approximately 380 nm to 780 nm. The reflective layer preferably has a high and uniform reflectance (over different angles of incidence) with respect to p-polarized and / or s-polarized radiation, thus ensuring a high-intensity and color-neutral image representation.

[0023] The polarization direction refers to the plane of incidence of the radiation on the composite pane. P-polarized radiation refers to radiation whose electric field oscillates in the plane of incidence. S-polarized radiation refers to radiation whose electric field oscillates perpendicular to the plane of incidence. The plane of incidence is defined by the incidence vector and the surface normal of the composite pane at the geometric center of the irradiated area.

[0024] In other words, the polarization, particularly the proportion of p- and s-polarized radiation, is determined at a point in the area irradiated by the image display device, preferably at the geometric center of the irradiated area. Since composite panes can be curved (for example, when designed as a windshield), which affects the plane of incidence of the image display device's radiation, slightly different polarization components may occur in the remaining areas, which is unavoidable for physical reasons.

[0025] In principle, the reflective layer can be single- or multi-layered, i.e., it can consist of a single layer of a single material or of multiple layers of different materials (i.e., multiple individual layers of different materials). If the reflective layer consists of multiple layers, it can also be considered a multi-layer coating, a thin-film stack, or a sequence of thin individual layers.

[0026] The reflective layer is designed to be suitable for reflecting light, preferably visible light. In particular, the layer thickness and refractive index of the reflective layer are selected such that constructive interference occurs at the reflective layer upon reflection of the incident light. The light generated by the imaging unit of a projection arrangement and directed onto the reflective layer generally has not just a single wavelength, but a wavelength range with many different wavelengths. Likewise, the incident light will not only be incident at a single angle of incidence, but rather at an angular range of many different angles of incidence. It is understood that the broadest possible reflection at different angles of incidence is advantageous, although in practice a satisfactory compromise must be found for this.The expert is familiar with reflection from thin layers and suitable conditions can be determined using simple experiments.

[0027] According to a first alternative of the invention, the reflection layer is a dielectric layer. According to a second alternative of the invention, the reflection layer is a silicon-based layer. According to a third alternative of the invention, the reflection layer is a carbide layer. With these reflection layers, broadband reflections with high reflectivity can be achieved based on constructive interference. In any case, the reflection layer is not a metallic layer, i.e., not a layer that contains or consists of metal. Furthermore, the reflection layer is not a holographic-optical element, i.e., light is reflected by the reflection layer and not diffracted. Accordingly, the reflection layer, which is designed in the form of a dielectric layer, according to the first alternative of the invention is not a polymer layer that is a component of a holographic-optical element.

[0028] In the first alternative of the invention, the reflective layer is a dielectric layer and contains or consists of one or more materials that are electrically non-conductive or weakly conductive, wherein existing charge carriers are not freely mobile (insulators). The dielectric layer can be a single-layer layer or a multi-layer layer, in particular a two-layer layer. In an advantageous embodiment of the invention, the dielectric layer is a two-layer layer (bilayer), wherein the two-layer layer consists of a first layer and a second layer, wherein the first layer contains or consists of an optically high-refractive material (with a high refractive index), and the second layer contains or consists of an optically low-refractive material (with a low refractive index). The terms "high-refractive" and "low-refractive" are common in the art.To avoid absolute specifications, the term "high refractive index" can also be interpreted as "higher refractive index" and the term "low refractive index" as "lower refractive index", whereby the relative specifications refer to the refractive indices of the two layers.

[0029] The particular advantage of the two-layer reflective coating lies in the possibility of easier production using a PVD process, especially sputtering, since single-layer reflective coatings with the desired layer thicknesses and refractive indices are, in our experience, more difficult to produce. Furthermore, two-layer coatings offer more degrees of freedom with regard to varying the layer thicknesses and refractive indices of the individual layers, in order to achieve the broadest possible reflection at different angles of incidence. For this purpose, the two layers of the two-layer reflective coating preferably have different thicknesses and / or different refractive indices.

[0030] Advantageously, the first layer with a material with a high optical refractive index has a refractive index in the range from 1.9 to 2.5 and / or the second layer with a material with a low optical refractive index has a refractive index in the range from 1.3 to 1.6. Particularly advantageously, the first layer with a material with a high optical refractive index has a thickness in the range from 50 to 100 nm, preferably 70 to 90 nm, and / or the second layer with a material with a low optical refractive index has a thickness in the range from 100 to 200 nm, preferably 110 to 150 nm. As experiments by the inventors have shown, these parameters allow light to be reflected with a particularly high bandwidth at different angles of incidence with high reflectivity. For example, the two-layer reflective coating consists of TiO x / SiO x (titanium oxide / silicon oxide), where TiO x a refractive index n = 2.45 and SiO x has a refractive index n = 1.45.

[0031] In the context of the present invention, refractive indices are generally given relative to a wavelength of 550 nm. Methods for determining refractive indices are known to those skilled in the art. The refractive indices specified in the context of the invention can be determined, for example, by ellipsometry, for which commercially available ellipsometers can be used.

[0032] The first layer with an optically high-refractive material is located between the glass pane and the second layer with an optically low-refractive material, i.e. the first layer with an optically high-refractive material is arranged closer to the glass pane than the second layer with an optically low-refractive material.

[0033] Preferably, when the reflective layer is configured as a two-layer reflective layer with a first layer of a material with a high optical refractive index and a second layer of a material with a low optical refractive index, the coated glass pane is arranged on the interior-facing surface (side IV) of the inner pane, with the reflective layer being located on the interior-facing surface (side VI) of the glass pane. With such an arrangement, the incident light can be reflected with a high bandwidth and particularly high reflectivity.

[0034] In the second alternative of the invention, the reflective layer is a silicon-based layer, i.e., the reflective layer contains or consists of silicon, wherein silicon is present in the form of undoped silicon, doped silicon, or a silicon compound. The silicon-based layer can be a single-layer layer or a multilayer layer, in particular a two-layer layer.

[0035] In an advantageous embodiment of the invention, the silicon-based layer is a single-layer layer, i.e., it consists of a single layer of the same material. Advantageously, the silicon-based layer contains or consists of undoped silicon. Alternatively, the silicon-based layer contains or consists of doped silicon doped with one or more dopants, the dopant preferably being selected from boron (B), aluminum (Al), and zirconium (Zr). As the inventors were able to demonstrate, such a reflective layer can reflect incident light across a broad band with high reflectivity.

[0036] In an advantageous embodiment of the invention, the silicon-based layer is a two-layer reflective layer (bilayer), wherein the two-layer reflective layer consists of a first layer and a second layer, wherein the first layer contains or consists of silicon doped with one or more dopants, wherein the dopant is selected in particular from boron (B), aluminum (Al), and zirconium (Zr), and the second layer contains or consists of a silicon compound. As the inventors were able to demonstrate, high reflectivity can be achieved over a broad band with such a reflective layer. For example, the two-layer reflective layer consists of Si(B) / SiAlN x , Si(ZrAl) / SiAlO x , or Si(B) / SiAlO x The dopant is indicated in parentheses. The first layer is located between the glass pane and the second layer, i.e., the first layer is positioned closer to the glass pane than the second layer.

[0037] Advantageously, the silicon-based layer has a thickness in the range of 10 to 100 nm, preferably 20 to 50 nm.

[0038] In a particular embodiment of the invention, a single- or double-layer reflective coating is arranged on the outside surface (side V) and the inside surface (side VI) of the glass pane. It is conceivable to apply a further layer of SiO2 to the reflective layer on the inside surface (side VI) of the glass pane to further increase reflectivity. The SiO2 layer preferably has a thickness in the range of 50 to 150 nm, more preferably in the range of 70 to 130 nm.

[0039] In the third alternative of the invention, the reflective layer is a carbide layer, i.e., the reflective layer contains or consists of a carbide compound. In an advantageous embodiment of the invention, the carbide layer is a single-layer layer, i.e., it consists of a single layer with the same substance. Advantageously, the carbide layer is a single-layer layer and has a layer thickness in the range of 10 to 100 nm, preferably 30 to 80 nm. Advantageously, the carbide layer contains or consists of TiC or ZrC. As the inventors have been able to demonstrate, high reflectivity can be achieved across a broad spectrum with such a reflective layer.

[0040] Unless otherwise stated, the specification of layer thicknesses refers to the geometric thickness of a layer. The methods for determining layer thicknesses are known to those skilled in the art. The layer thicknesses specified within the scope of the invention can be determined, for example, by ellipsometry, for which commercially available ellipsometers can be used.

[0041] As described above, in the composite pane according to the invention, at least one masking layer is arranged in a region of the composite pane. Preferably, the masking layer is arranged in an edge region of the composite pane, which typically borders the edge of the pane. The great advantage of this arrangement arises when the composite pane is used in a vehicle as a windshield, since the masking layer, when arranged in an edge region, lies outside the driver's primary field of vision.

[0042] The masking layer is preferably arranged at least along the lower edge and adjacent to the lower edge. This results in a rectangular opaque strip arranged along the lower edge in a plan view of the laminated pane.

[0043] In a particular embodiment of the composite pane according to the invention, the masking layer is designed in a frame-shaped manner all the way around. In a section in which the glass pane and thus also the reflective layer applied thereto are arranged in overlap with the masking layer, the frame-shaped masking layer is preferably provided with a widening, i.e. has a greater width (dimension perpendicular to the extension) than in other sections. In this way, the masking layer can be suitably adapted to the dimensions of the glass pane with the reflective layer applied thereto. In one embodiment, the masking layer is thus designed in a frame-shaped manner all the way around and has, in particular, in a section that overlaps with the glass pane, a greater width than in sections different therefrom.

[0044] The glass pane with the reflective layer applied thereto preferably has a substantially rectangular shape extending in a region near the bottom edge between the two side edges. Particularly preferably, the edges of the glass pane do not extend to the side edges and the bottom edge, but are spaced from them, for example, by 2 cm to 5 cm.

[0045] The masking layer within the meaning of the invention is a layer that prevents visibility through the composite pane. A maximum of 5%, preferably a maximum of 2%, particularly preferably a maximum of 1%, in particular a maximum of 0.1%, of the light of the visible spectrum is transmitted through the masking layer. The masking layer is therefore an opaque masking layer, preferably a black masking layer. The masking layer is preferably a coating comprising one or more layers. Alternatively, the masking layer can also be a colored region of the thermoplastic intermediate layer. According to a preferred embodiment of the composite pane, the masking layer consists of a single layer. This has the advantage of particularly simple and cost-effective production of the composite pane, since only a single layer needs to be formed for the masking layer.The masking layer is in particular an opaque cover print made of a dark, preferably black, enamel.

[0046] Advantageously, the at least one masking layer is formed as an opaque masking print arranged on the interior-side surface (side II) of the outer pane, in particular made of a dark, preferably black, enamel. Alternatively or additionally, the masking layer is formed as an opaque masking print arranged on the exterior-side surface (side III) of the inner pane, in particular made of a dark, preferably black, enamel. In particular, a first opaque masking print can be arranged on the interior-side surface (side II) of the outer pane and a second opaque masking print can be arranged on the exterior-side surface (side III) of the inner pane.

[0047] If the glass pane coated with at least one reflective layer is arranged on the outer surface (side III) of the inner pane, a masking layer is located between the outer pane and the coated glass pane. If an additional masking layer (e.g., an opaque masking print) is arranged closer to the inner pane, this masking layer is provided with one or more perforations to ensure a clear view of the reflective layer from the interior.

[0048] In an alternative embodiment, the masking layer is formed as an opaquely colored region of the thermoplastic intermediate layer. In one embodiment, the thermoplastic intermediate layer is formed in one piece and is opaquely colored in one region.

[0049] A masking layer formed as an opaque colored region of the thermoplastic intermediate layer can also be realized by using a thermoplastic intermediate layer composed of an opaque thermoplastic film and a transparent thermoplastic film. The opaque thermoplastic film and transparent thermoplastic film are preferably arranged offset from one another so that the two films do not overlap when viewed through the composite pane. The transparent and opaque films consist of the same plastic or preferably contain the same plastic. The materials on which the opaque film and the transparent film can be formed are those also described for the thermoplastic intermediate layer. The opaque film is preferably a colored film that can have various colors, in particular black.

[0050] The composite pane according to the invention can, in particular, have an opaque masking print arranged on the interior-side surface of the inner pane, in particular at least in the area where the glass pane is arranged. Such a masking print on the interior-side surface of the inner pane improves the adhesion properties of the surface to an adhesive layer. The opaque masking print is preferably frame-shaped.

[0051] In a preferred embodiment of the composite pane according to the invention, a reflective layer for reflecting light is arranged on the interior-side surface of the glass pane and a protective layer is arranged on this reflective layer.

[0052] In a further preferred embodiment of the composite pane according to the invention, a reflective layer for reflecting light is arranged on both the interior surface of the glass pane and the exterior surface of the glass pane, and a protective layer is arranged on the reflective layer arranged on the interior surface of the glass pane. No protective layer is necessary for the reflective layer arranged on the exterior surface of the glass pane, since this reflective layer is bonded to the interior pane via the adhesive layer and is thus protected. Optionally, however, a protective layer can also be arranged on the reflective layer arranged on the exterior surface of the glass pane.

[0053] The protective layer is preferably transparent and applied flatly, in particular congruently, to the reflective layer. The protective layer is preferably a polymer based on polyacrylates, polyoximes, alkyd resins, polyurethanes, or mixtures thereof. The protective layer preferably has a thickness of 50 nm to 10 pm, and particularly preferably of 100 nm to 5 pm. In particular, the protective layer is not made of a glass material, i.e., the protective layer is not a glass pane. The protective layer protects the reflective layer from mechanical damage such as scratches. It can also serve to increase the durability of the reflective layer.

[0054] In a particularly preferred embodiment of the invention, the protective layer is an easy-to-clean layer and / or an anti-fingerprint layer. Within the meaning of the invention, an easy-to-clean layer means that dirt in the form of, for example, fingerprints, grease stains, and dirt particles on the protective layer can be removed from the protective layer using a cloth, preferably a microfiber cloth. Grease-dissolving or abrasive cleaning agents as well as solvents, for example, alcohol-based ones, are therefore largely avoided for cleaning the protective layer. Within the meaning of the invention, an anti-fingerprint layer means a layer in which fingerprints adhering to the protective layer are barely or not at all visually perceptible.Fingerprints are specifically the fatty components of a human finger that can remain on a surface when touching it and can have an unsightly effect.

[0055] The adhesive layer is preferably a thermoplastic layer or an optically clear adhesive (OCA). Suitable optically clear adhesives, so-called optical clear adhesives (OCA), are known to those skilled in the art. An adhesive layer formed as a thermoplastic layer contains at least one thermoplastic polymer, preferably ethylene vinyl acetate (EVA), polyvinyl butyral (PVB) or polyurethane (PU) or mixtures or copolymers or derivatives thereof, particularly preferably PVB. The thermoplastic layer is typically formed from a thermoplastic film (connecting film). The thickness of the thermoplastic layer is preferably from 0.2 mm to 2 mm, particularly preferably from 0.3 mm to 1 mm, for example 760 μm. The thermoplastic layer can be formed by a single film or by more than one film. The glass pane can be firmly connected to the inner pane, for example by lamination.

[0056] The composite pane is preferably curved in one or more spatial directions, as is usual for motor vehicle windows, with typical radii of curvature being in the range from approximately 10 cm to approximately 40 m. However, the composite pane can also be flat, for example if it is intended as a pane for buses, trains or tractors. The thermoplastic intermediate layer, via which the outer pane is connected to the inner pane, contains at least one thermoplastic polymer, preferably ethylene vinyl acetate (EVA), polyvinyl butyral (PVB) or polyurethane (PU) or mixtures or copolymers or derivatives thereof, particularly preferably PVB. The thermoplastic intermediate layer is typically formed from a thermoplastic film (connecting film). The thickness of the thermoplastic intermediate layer is preferably from 0.2 mm to 2 mm, particularly preferably from 0.3 mm to 1 mm, for example 760 μm.The thermoplastic intermediate layer can be formed by a single film or by multiple films. The thermoplastic intermediate layer can also be a film with functional properties, for example, a film with acoustic damping properties.

[0057] The outer pane and inner pane preferably contain or consist of glass, particularly preferably flat glass, float glass, quartz glass, borosilicate glass, soda-lime glass, aluminosilicate glass, or clear plastics, preferably rigid clear plastics, in particular polyethylene, polypropylene, polycarbonate, polymethyl methacrylate, polystyrene, polyamide, polyester, polyvinyl chloride and / or mixtures thereof.

[0058] The outer pane and the inner pane can be clear and colorless, but also tinted or colored. In a preferred design, the total transmission through the windshield in the main viewing area is greater than 70% (illuminant A). The term "total transmission" refers to the procedure for testing the light transmittance of motor vehicle windows specified in ECE-R 43, Annex 3, Section 9.1. The outer pane and the inner pane can independently be untempered, partially tempered, or toughened. If at least one of the panes is to be tempered, this can be thermally or chemically toughened.

[0059] The thickness of the outer pane and the inner pane can vary widely and thus be adapted to the requirements of the individual case. The outer pane and the inner pane preferably have thicknesses of 0.5 mm to 5 mm, particularly preferably of 1 mm to 3 mm, most preferably of 1.6 mm to 2.1 mm. For example, the outer pane has a thickness of 2.1 mm and the inner pane a thickness of 1.6 mm. However, the outer pane or in particular the inner pane can also be a thin glass with a thickness of, for example, 0.55 mm. The glass pane preferably contains alumino-silicate glass, borosilicate glass, alumino-borosilicate glass, or consists thereof. The glass pane can be toughened, semi-toughened or prestressed.

[0060] The composite pane according to the invention can comprise one or more additional intermediate layers, in particular functional intermediate layers. An additional intermediate layer can, in particular, be an intermediate layer with acoustically dampening properties, an infrared-reflecting intermediate layer, an infrared-absorbing intermediate layer, a UV-absorbing intermediate layer, an at least partially colored intermediate layer, and / or an at least partially tinted intermediate layer. If several additional intermediate layers are present, these can also have different functions.

[0061] The invention also relates to a projection arrangement comprising a composite pane according to the invention and an imaging unit directed onto the reflection layer.

[0062] The invention therefore also relates to a projection arrangement which comprises: a composite pane, comprising an outer pane with an outer surface and an interior surface, a thermoplastic intermediate layer, an inner pane with an outer surface and an interior surface, at least one masking layer which is arranged in a region of the composite pane between the outer pane and the inner pane, an adhesive layer and a glass pane with an outer surface and an interior surface and a thickness of 20 μm to 500 μm, wherein the thermoplastic intermediate layer is arranged between the outer pane and the inner pane, the adhesive layer is arranged between the inner pane and the glass pane, a reflective layer for reflecting light is arranged on the outer surface of the glass pane and / or on the interior surface of the glass pane,and wherein the glass pane is arranged in a region of the composite pane that, when viewed perpendicularly through the composite pane, lies entirely within the region in which the masking layer is arranged, and an imaging unit directed toward the reflective layer. In particular, the combination of the reflective layer with the masking layer located behind it from the perspective of a vehicle occupant results in good image visibility in a projection arrangement according to the invention, even in external sunlight and when using low-light imaging units. Even under these conditions, the image generated by the imaging unit appears bright and is clearly recognizable. This enables a reduction in the power of the imaging unit and thus reduced energy consumption.

[0063] From the perspective of a vehicle occupant, the reflective layer is positioned spatially in front of the masking layer when viewed through the inner pane. The area of ​​the composite pane where the reflective layer is located therefore appears opaque. The expression "viewing through the composite pane" means that the view through the composite pane starts from the interior-side surface of the composite pane. For the purposes of the present invention, "spatially in front" means that the reflective layer is positioned spatially farther away from the outer surface of the outer pane than the masking layer. The masking layer is preferably widened at least in the area that overlaps with the reflective layer and in which the composite pane is used to display images.This means that the masking layer in this area, viewed perpendicular to the nearest section of the peripheral edge of the laminated pane, has a greater width than in other sections. The masking layer can thus be adapted to the dimensions of the reflective layer.

[0064] The imaging unit of the projection arrangement emits light and is arranged adjacent to the interior-side surface of the inner pane such that the imaging unit irradiates this surface, with the light being reflected by the reflective layer of the composite pane. The reflective layer preferably reflects at least 10%, more preferably at least 50%, most preferably at least 80%, and in particular at least 90% of the light incident on the reflective layer in a wavelength range from 400 nm to 700 nm and at angles of incidence from 55° to 80°. This is advantageous in order to achieve the greatest possible brightness of an image emitted by the imaging unit and reflected by the reflective layer.

[0065] The imaging unit is used to emit an image and can therefore also be referred to as a projector, display device, or image display device. A display or another device known to those skilled in the art can also be used as the imaging unit. The imaging unit is preferably a display, particularly preferably an LCD display, LED display, OLED display, or electroluminescent display, in particular an LCD display. Displays have a low installation height and are therefore easy and space-saving to integrate into the dashboard of a vehicle. Furthermore, displays are significantly more energy-efficient to operate than other imaging units. The comparatively lower brightness of displays is entirely sufficient in the inventive combination of the reflective layer and the masking layer behind it.The radiation from the imaging unit preferably strikes the composite pane in the region of the reflective layer at an angle of incidence of 55° to 80°, preferably 62° to 77°. The angle of incidence is the angle between the incidence vector of the radiation from the image display device and the surface normal at the geometric center of the reflective layer.

[0066] By arranging the reflection layer on the outside surface and / or the inside surface of a glass pane having a thickness of 20 pm to 500 pm, which is bonded to the inside surface of the inner pane according to an embodiment of the invention, the occurrence of a disturbing ghost image is avoided.

[0067] In a projection arrangement with a reflective layer applied to the interior surface of the glass pane, the desired virtual image is created by reflection from the reflective layer and no ghost image occurs.

[0068] In a projection arrangement with a reflective layer applied to the outside surface of the glass pane, the desired virtual image is created by reflection from the reflective layer and, in addition, a second virtual image, the so-called ghost image, is created by reflection from the inside surface of the glass pane.

[0069] In a projection arrangement with a reflective layer applied to the outside surface of the glass pane and a reflective layer applied to the inside surface of the glass pane, a first virtual image is generated by reflection from the reflective layer applied to the outside surface of the glass pane, and a second virtual image is additionally generated from the reflective layer applied to the inside surface of the glass pane. However, with the low thickness of the glass pane according to the invention, the spatial offset between the first virtual image and the ghost image, or between the first virtual image and the second virtual image, is sufficiently small not to be noticeable. The effect is based on the typical angular acuity of the human eye: the thin glass pane according to the invention leads to an offset between the first virtual image and the ghost image, orbetween the first virtual image and the second virtual image, which is no longer resolvable for the human eye.

[0070] The preferred embodiments of the composite pane according to the invention described above also apply accordingly to the projection arrangement according to the invention and vice versa.

[0071] The invention also relates to a method for producing a composite pane according to the invention, comprising: a) producing a composite from an outer pane with an outer surface and an interior surface, a thermoplastic intermediate layer, and an inner pane with an outer surface and an interior surface, wherein the thermoplastic intermediate layer is arranged between the outer pane and the inner pane and at least one masking layer is arranged in a region between the outer pane and the inner pane; b) providing a glass pane with an outer surface and an interior surface, wherein a reflective layer for reflecting light is arranged on the outer surface of the glass pane and / or on the interior surface of the glass pane;c) bonding the glass pane to the inner pane via an adhesive layer to form a composite pane, such that the glass pane is arranged in a region of the composite pane which, when viewed perpendicularly through the composite pane, lies entirely in the region in which the masking layer is arranged;

[0072] Steps a), b), and c) can be performed in the specified order, simultaneously, or in any order. In particular, step c) can be performed before or after step a). Step a) occurs after step c) if the coated glass pane is applied to the outside surface (side III) of the inner pane. Step c) can be performed after step a) if the coated glass pane is applied to the inside surface (side IV) of the inner pane.

[0073] As explained above, the glass pane is arranged in a region of the composite pane which, when viewed perpendicularly through the composite pane, lies entirely in the region in which the masking layer is arranged. Thus, the glass pane has smaller external dimensions than the outer pane and the inner pane of the composite pane. The glass pane can be provided in step b), for example, by applying a reflective layer over the entire surface of the interior and / or the exterior surface of an uncoated glass pane which, in terms of external dimensions, i.e., width and length, is larger than desired, and then cutting out a section having the desired dimensions from such a coated glass pane, for example by means of a laser cutting process.A reflective layer can be selectively arranged over the glass pane provided with the reflective layer in a region of the composite pane. Providing the glass pane in step b) can additionally comprise applying a protective layer to the reflective layer applied to the interior surface and / or the exterior surface. The protective layer is preferably applied to the reflective layer by spraying or squirting, for example, using a pressure atomizer.

[0074] If the composite pane is to be curved, a curved outer pane and a curved inner pane are inserted in step a). The glass pane with the reflective coating is flexible due to its thinness and adapts to the curved inner pane in step c). This is an advantage of the method according to the invention. In the method according to the invention, the coating with the reflective coating is applied to a flat substrate.

[0075] The production of a composite in step a) or in step c) can be carried out by means of lamination processes familiar to the person skilled in the art.

[0076] When preparing the glass pane in step b), the reflective layer can be applied using generally known coating methods, such as magnetron sputtering or cold gas spraying. The preferred embodiments of the composite pane according to the invention described above also apply accordingly to the method according to the invention for producing a composite pane according to the invention.

[0077] The invention also relates to the use of a composite pane according to the invention as a vehicle pane in means of transport for traffic on land, in the air or on water, in particular in motor vehicles and in particular as a windscreen for a head-up display.

[0078] The various embodiments of the invention can be implemented individually or in any combination. In particular, the aforementioned features can be used not only in the specified combinations, but also in other combinations or on their own, without departing from the scope of the present invention.

[0079] The invention is explained in more detail below using exemplary embodiments, with reference to the accompanying figures. They show, in simplified form and not to scale:

[0080] Fig. 1 is a plan view of an embodiment of the composite pane according to the invention,

[0081] Fig. 2 shows a cross section through the embodiment shown in Figure 1,

[0082] Fig. 3 shows a cross section through a further embodiment of the composite pane according to the invention,

[0083] Fig. 4 shows a cross section through a further embodiment of the composite pane according to the invention,

[0084] Fig. 5 shows a cross section through a further embodiment of the composite pane according to the invention,

[0085] Fig. 6 shows a cross section through a further embodiment of the composite pane according to the invention, Fig. 7 shows a cross section through a further embodiment of the composite pane according to the invention,

[0086] Fig. 8 shows a cross section through a further embodiment of the composite pane according to the invention,

[0087] Fig. 9 shows a cross section through a further embodiment of the composite pane according to the invention,

[0088] Fig. 10 shows a cross section through a further embodiment of the composite pane according to the invention,

[0089] Fig. 11 shows a cross section through a further embodiment of the composite pane according to the invention,

[0090] Fig. 12 shows a cross section through a further embodiment of the composite pane according to the invention,

[0091] Fig. 13 shows a cross section through a further embodiment of the composite pane according to the invention,

[0092] Fig. 14 shows a cross section through a further embodiment of the composite pane according to the invention,

[0093] Fig. 15 shows a cross section through a further embodiment of the composite pane according to the invention,

[0094] Fig. 16 shows a cross section through an embodiment of a projection arrangement according to the invention,

[0095] Fig. 17 a cross-section through a coated glass pane,

[0096] Fig. 18 shows a cross section through another coated glass pane, Fig. 19 shows a cross section through another embodiment of the composite pane according to the invention,

[0097] Fig. 20 shows a cross section through a further embodiment of the composite pane according to the invention,

[0098] Fig. 21 shows a cross section through a further embodiment of the composite pane according to the invention, and

[0099] Fig. 22 shows an embodiment of the method according to the invention using a flow chart.

[0100] Figure 1 shows a plan view of an embodiment of the composite pane 100 according to the invention, and Figure 2 shows the cross-section through the composite pane 100 shown in Figure 1 along the section line XX'. The composite pane 100 shown in Figures 1 and 2 has an upper edge O, a lower edge U, and two side edges S. The composite pane 100 further comprises an outer pane 1 with an outside surface I and an inside surface II, an inner pane 2 with an outside surface III and an inside surface IV, a thermoplastic intermediate layer 3, a masking layer 4, an adhesive layer 5, and a glass pane 6 with an outside surface V and an inside surface VI.The thermoplastic intermediate layer 3 is arranged between the outer pane 1 and the inner pane 2, the inner pane 2 is arranged between the outer pane 1 and the glass pane 6, and the adhesive layer 5 is arranged between the inner pane 2 and the glass pane 6. The outer pane 1, the thermoplastic intermediate layer 3, and the inner pane 2 are arranged one above the other over their entire surface. The masking layer 4 is arranged between the outer pane 1 and the inner pane 2 in a region of the composite pane 100 whose areal extent is smaller than the areal extent of the composite pane 100, i.e., the masking layer 4 does not extend over the entire surface of the composite pane 100.In the embodiment shown in Figures 1 and 2, the masking layer 4 is formed as a first opaque cover print arranged on the interior-side surface II of the outer pane 1 and is arranged only in an edge region of the composite pane 100 bordering the lower edge U. The glass pane 6 is arranged in a region of the composite pane 100 which, when viewed perpendicularly through the composite pane 100, lies entirely in the region in which the masking layer 4 is arranged. The glass pane 6 is thus smaller in terms of its external dimensions than the inner pane 2. The outer surface V of the glass pane 6 is connected to the interior-side surface IV of the inner pane 2 via the adhesive layer 5. In the embodiment shown in Figure 2, a reflective layer 7 for reflecting light is arranged on the interior-side surface VI of the glass pane 6.

[0101] The glass pane 6 is made, for example, of aluminosilicate glass and has a thickness of 70 μm. The thermoplastic intermediate layer 3 contains, for example, PVB and has a thickness of 0.76 mm. The outer pane 1 is made, for example, of soda-lime glass and is 2.1 mm thick. The inner pane 2 is made, for example, of soda-lime glass and is 1.6 mm thick.

[0102] The adhesive layer 5 consists, for example, of an optically clear adhesive. Alternatively, the adhesive layer 5 consists of a thermoplastic material, such as polyvinyl butyral (PVB), and the glass pane 6 is bonded to the inner pane 2 by lamination.

[0103] It is understood that the composite pane 100 may have any suitable geometric shape and / or curvature. Typically, the composite pane 100 is a curved composite pane. For example, the composite pane 100 is the windshield of a motor vehicle.

[0104] In the embodiment shown in Figures 1 and 2, the masking layer 4 extends between the two side edges S of the composite pane 100 and, starting from the lower edge U of the composite pane 100, has a width of, for example, 30 cm.

[0105] Figure 3 shows a cross-section through another embodiment of the composite pane 100 according to the invention. The embodiment shown in cross-section in Figure 3 (analogous to Figure 2) differs from the embodiment shown in Figure 2 only in that a protective layer 8 is additionally applied over the entire surface of the reflective layer 7 applied to the interior-side surface VI of the glass pane 6. The protective layer 8 is, for example, a polymer based on polyacrylates, polyoximes, alkyd resins, polyurethanes, or mixtures thereof. The protective layer 8 has, for example, a thickness of 500 nm.

[0106] Figure 4 shows a cross section through a further embodiment of the composite pane 100 according to the invention. The embodiment shown in cross section in Figure 4 (analogous to Figure 2) differs from that shown in Figure 2 only in that the masking layer 4 is not formed as a first opaque cover print arranged on the interior-side surface II of the outer pane 1, but is formed as a first opaque cover print arranged on the exterior-side surface III of the inner pane 2.

[0107] Figure 5 shows a cross section through a further embodiment of the composite pane 100 according to the invention. The embodiment shown in cross section in Figure 5 differs from that shown in Figure 3 only in that the masking layer 4 is not formed as a first opaque cover print arranged on the interior-side surface II of the outer pane 1, but is formed as a first opaque cover print arranged on the exterior-side surface III of the inner pane 2.

[0108] Figure 6 shows a cross section through a further embodiment of the composite pane 100 according to the invention. The embodiment shown in cross section in Figure 6 differs from that shown in Figure 2 only in that the masking layer 4 is not formed as a first opaque cover print arranged on the interior-side surface II of the outer pane 1, but is formed as an opaquely colored region of the thermoplastic intermediate layer 3.

[0109] Figure 7 shows a cross section through a further embodiment of the composite pane 100 according to the invention. The embodiment shown in cross section in Figure ? differs from that shown in Figure 3 only in that the masking layer 4 is not designed as a first opaque cover print arranged on the interior-side surface II of the outer pane 1, but is designed as an opaque-colored region of the thermoplastic intermediate layer 3.

[0110] Figure 8 shows a cross-section through a further embodiment of the composite pane 100 according to the invention. The embodiment shown in cross-section in Figure 8 differs from that shown in Figure 2 only in that the reflective layer 7 is not arranged on the interior-side surface VI of the glass pane 6, but rather on the exterior-side surface V of the glass pane 6. Optionally, in this embodiment too, a protective layer can additionally be arranged on the reflective layer 7 directly adjacent to the adhesive layer 5. Figure 9 shows a cross-section through a further embodiment of the composite pane 100 according to the invention. The embodiment shown in cross-section in Figure 9 differs from that shown in Figure 2 only in that, in addition to the reflective layer 7 arranged on the interior-side surface VI of the glass pane 6, a reflective layer 7 is also arranged on the exterior-side surface V of the glass pane 6.

[0111] Figure 10 shows a cross-section through a further embodiment of the composite pane 100 according to the invention. The embodiment shown in cross-section in Figure 10 differs from that shown in Figure 9 only in that a protective layer 8 is additionally applied to the reflective layer 7 applied to the interior-side surface VI of the glass pane 6. The protective layer 8 is, for example, a polymer based on polyacrylates, polyoximes, alkyd resins, polyurethanes, or mixtures thereof. The protective layer 8 has, for example, a thickness of 500 nm. Optionally, in this embodiment too, a further protective layer can be arranged on the reflective layer 7 applied to the exterior surface V of the glass pane 6, directly adjacent to the adhesive layer 5.

[0112] Figure 11 shows a cross-section through another embodiment of the composite pane 100 according to the invention. The embodiment shown in cross-section in Figure 11 differs from that shown in Figure 2 only in that the composite pane 100 additionally has a second opaque cover print 9 applied to the interior-side surface IV of the inner pane 2. The second opaque cover print 9 is, for example, frame-shaped.

[0113] Figure 12 shows a cross-section through another embodiment of the composite pane 100 according to the invention. The embodiment shown in cross-section in Figure 12 differs from the embodiment shown in Figure 3 only in that the composite pane 100 additionally has a second opaque cover print 9 applied to the interior-side surface IV of the inner pane 2. The second opaque cover print 9 is, for example, frame-shaped.

[0114] Figure 13 shows a cross-section through another embodiment of the composite pane 100 according to the invention. The embodiment shown in cross-section in Figure 13 differs from the embodiment shown in Figure 8 only in that the composite pane 100 additionally has a second opaque cover print 9 applied to the interior-side surface IV of the inner pane 2. The second opaque cover print 9 is, for example, frame-shaped.

[0115] Figure 14 shows a cross-section through another embodiment of the composite pane 100 according to the invention. The embodiment shown in cross-section in Figure 14 differs from the embodiment shown in Figure 9 only in that the composite pane 100 additionally has a second opaque cover print 9 applied to the interior-side surface IV of the inner pane 2. The second opaque cover print 9 is, for example, frame-shaped.

[0116] Figure 15 shows a cross-section through another embodiment of the composite pane 100 according to the invention. The embodiment shown in cross-section in Figure 15 differs from the embodiment shown in Figure 10 only in that the composite pane 100 additionally has a second opaque cover print 9 applied to the interior-side surface IV of the inner pane 2. The second opaque cover print 9 is, for example, frame-shaped.

[0117] Fig. 16 shows a cross-section through an embodiment of the projection arrangement 101 according to the invention. The projection arrangement 101 shown in Figure 16 comprises a composite pane 100 and an imaging unit 10. The projection arrangement 101 has an imaging unit 10. The imaging unit 10 serves to generate p-polarized light and / or s-polarized light (image information), which is directed onto the reflective layer 7 and is reflected by the reflective layer 7 as reflected light into the vehicle interior, where it can be perceived by an observer, e.g. the driver. The reflective layer 7 is suitably designed to reflect the light of the imaging unit 10. The light preferably strikes the reflective layer 7 at an angle of incidence of 55° to 80°, in particular of 62° to 77°. The imaging unit 10 is, for example, a display, in particular an LCD display.Preferably, the imaging unit 10 serves to generate only p-polarized light, which can be clearly seen, in particular, with polarizing sunglasses having an s-polarization filter.

[0118] In the following, embodiments of the coated glass pane 6 (Figures 17 and 18), as well as further embodiments of the composite pane 100 according to the invention (Figures 19 to 21), are illustrated using cross-sections. In the further embodiments of Figures 19 to 21 of the composite pane 100 according to the invention, the coated glass pane 6 is arranged on the outer surface (side III) of the inner pane 2. These embodiments can equally be used in the projection arrangement 101 illustrated by way of example in Figure 16.

[0119] Figure 17 shows a cross-section of an embodiment of the coated glass pane 6. The cross-section is only shown in the region of the glass pane 6. The glass pane 6 is coated with a single-layer reflective layer 7. According to one embodiment, the single-layer reflective layer 7 is a dielectric layer or a silicon-based layer that contains or consists of, for example, undoped silicon or doped silicon. Doped silicon is doped, for example, with boron (B), aluminum (Al), and / or zirconium (Zr). Alternatively, the single-layer reflective layer 7 is, for example, a carbide layer made of, for example, TiC or ZrC.

[0120] Figure 18 shows a cross-section of another embodiment of the coated glass pane 6. The cross-section is shown only in the area of ​​the glass pane 6. The glass pane 6 is coated with a two-layer reflective coating 7 (bilayer). The two-layer reflective coating 7 consists of a first layer 11 and a second layer 12. According to one embodiment, the first layer 11 consists of a material with a high optical refractive index, and the second layer 12 consists of a material with a low optical refractive index, e.g., TiOx / SiOx. According to an alternative embodiment, the first layer 11 consists of doped silicon, and the second layer 12 consists of a silicon compound, e.g., Si(B) / SiAlN. x , Si(ZrAl) / SiAlO x , or Si(B) / SiAlO x .

[0121] Figure 19 shows a cross-section through a further embodiment of the composite pane 100 according to the invention. The cross-section is only shown in the region of the glass pane 6. The embodiment shown in cross-section in Figure 19 differs from that shown in Figure 2 only in that the coated glass pane 6 is attached to the outside surface III of the inner pane 2. The adhesive layer 5 is located between the glass pane 6 and the inner pane 2. The reflective layer 7 is located between the glass pane 6 and the inner pane 2, ie is arranged on the inside surface VI of the glass pane 6.

[0122] Figure 20 shows a cross-section through a further embodiment of the composite pane 100 according to the invention. The cross-section is only shown in the region of the glass pane 6. The embodiment shown in cross-section in Figure 20 differs from that shown in Figure 4 in that the coated glass pane 6 is attached to the outer surface III of the inner pane 2. The adhesive layer 5 is located between the glass pane 6 and the inner pane 2. The reflective layer 7 is located between the glass pane 6 and the inner pane 2, i.e. is arranged on the interior-side surface VI of the glass pane 6. In addition, the masking layer 4, which is designed as a first opaque cover print arranged on the outer surface III of the inner pane 2, has one or more openings so that light from the imaging unit 10 can strike the reflective layer 7 and be reflected by it.

[0123] Figure 21 shows a cross-section through a further embodiment of the composite pane 100 according to the invention. The cross-section is only shown in the region of the glass pane 6. The embodiment shown in cross-section in Figure 21 differs from that shown in Figure 6 only in that the coated glass pane 6 is attached to the outside surface III of the inner pane 2. The adhesive layer 5 is located between the glass pane 6 and the inner pane 2. The reflective layer 7 is located between the glass pane 6 and the inner pane 2, ie is arranged on the inside surface VI of the glass pane 6.

[0124] In Fig. 22, an embodiment of the method according to the invention is shown using a flow chart.

[0125] In a step S1, a composite is produced from an outer pane 1 with an outer surface I and an inner surface II, a thermoplastic intermediate layer 3 and an inner pane 2 with an outer surface III and an inner surface IV, wherein the thermoplastic intermediate layer 3 is arranged between the outer pane 1 and the inner pane 2 and a masking layer 4 is arranged in a region between the outer pane 1 and the inner pane 2.

[0126] In a step S2, a glass pane 6 having an outside surface V and an inside surface VI, wherein on the outside surface V of the glass pane

[0127] 6 and / or on the interior surface VI of the glass pane 6 a reflective layer

[0128] 7 is provided for reflecting light. In a step S3, the glass pane 6 is bonded to the inner pane 2 of the composite via an adhesive layer 5 to form a composite pane 100, such that the glass pane 6 is arranged in a region of the composite pane 100 which, when viewed perpendicularly through the composite pane 100, lies entirely in the region in which the masking layer 4 is arranged.

[0129] Steps S1, S2 and S3 can be performed in any order or simultaneously.

[0130] From the above, it can be seen that the invention provides an improved composite pane that reflects the image from a projector and allows the virtual image to be visually perceived with sufficient brightness and high contrast, thus reliably ensuring good recognizability, especially of safety-relevant information, in all weather and lighting conditions. Furthermore, unwanted secondary images can be avoided. The composite pane can be manufactured efficiently and cost-effectively in industrial series production, and its production can be easily implemented using common manufacturing processes.

[0131] List of reference symbols:

[0132] 100 composite panes

[0133] 101 Projection arrangement

[0134] 1 outer pane

[0135] 2 inner pane

[0136] 3 thermoplastic intermediate layer

[0137] 4 Masking layer

[0138] 5 adhesive layer

[0139] 6 glass pane

[0140] 7 Reflective layer

[0141] 8 protective layer

[0142] 9 second opaque cover print

[0143] 10 imaging unit

[0144] 11 first layer

[0145] 12 second layer

[0146] O Top edge of the laminated pane 100

[0147] U Bottom edge of the laminated pane 100

[0148] S Side edge of the laminated pane 100

[0149] I outside surface of the outer pane 1

[0150] II Interior surface of the outer pane 1

[0151] III outer surface of the inner pane 2

[0152] IV Interior surface of the inner pane 2

[0153] V outer surface of the glass pane 6

[0154] VI Interior surface of the glass pane 6

Claims

Patent claims 1. A composite pane (100) comprising an outer pane (1) with an outer surface (I) and an interior surface (II), a thermoplastic intermediate layer (3), an inner pane (2) with an outer surface (III) and an interior surface (IV), at least one masking layer (4), an adhesive layer (5), a glass pane (6) with an outer surface (V) and an interior surface (VI) and a thickness of 20 μm to 500 μm, wherein the thermoplastic intermediate layer (3) is arranged between the outer pane (1) and the inner pane (2), the at least one masking layer (4) is arranged between the outer pane (1) and the inner pane (2) in a region of the composite pane (100), the adhesive layer (5) is arranged between the inner pane (2) and the glass pane (6),at least one reflective layer (7) for reflecting light is arranged on the outer surface (V) of the glass pane (6) and / or on the inner surface (VI) of the glass pane (6), wherein the glass pane (6) is arranged in a region of the composite pane (100) which, when viewed perpendicularly through the composite pane (100), lies entirely in the region in which the at least one masking layer (4) is arranged, and wherein the at least one reflective layer (7) contains or consists of i) a dielectric layer, or ii) a silicon-based layer, or iii) a carbide layer.

2. Composite pane (100) according to claim 1, wherein the dielectric layer is a single-layer or double-layer layer, the double-layer layer consisting of a first layer (11) and a second layer (12), the first layer (11) containing or consisting of an optically high-refractive-index material and the second layer (12) containing or consisting of an optically low-refractive-index material.

3. Composite pane (100) according to claim 2, wherein the first layer (11) with an optically high-refractive material has a refractive index in the range from 1.9 to 2.5 and / or the second layer (12) with an optically low-refractive material has a refractive index in the range from 1.3 to 1.

6.

4. Composite pane (100) according to claim 3, wherein the first layer (11) with an optically high-refractive material has a thickness in the range of 50 to 100 nm, in particular 70 to 90 nm, and / or the second layer (12) with an optically low-refractive material has a thickness in the range of 100 to 200 nm, in particular 110 to 150 nm.

5. Composite pane (100) according to claim 1, wherein the silicon-based layer is a single-layer layer and contains or consists of i) non-doped silicon, or ii) doped silicon doped with one or more dopants, wherein the dopant is in particular selected from boron (B), aluminum (Al) and zirconium (Zr).

6. Composite pane (100) according to claim 1, wherein the silicon-based layer is a two-layer layer consisting of a first layer (11) which contains or consists of silicon doped with one or more dopants, wherein the dopant is selected in particular from boron (B), aluminum (Al) and zirconium (Zr), and a second layer (12) which contains or consists of a silicon compound.

7. Composite pane (100) according to claim 5 or 6, wherein the silicon-based layer has a thickness in the range of 10 to 100 nm, in particular 20 to 50 nm.

8. Composite disc (100) according to claim 1, wherein the carbide layer is a single-layer layer and has a layer thickness in the range of 10 to 100 nm, in particular 30 to 80 nm.

9. Composite pane (100) according to one of claims 1 to 8, in which the glass pane (6) is arranged on the interior-side surface (IV) or on the exterior-side surface (III) of the inner pane (2).

10. Composite pane (100) according to one of claims 1 to 9, in which the glass pane (6) has a thickness of 50 pm to 300 pm, in particular of 50 pm to 100 pm.

11. Composite pane (100) according to one of claims 1 to 10, wherein the at least one masking layer (4) is formed as i) an opaque cover print arranged on the interior-side surface (II) of the outer pane (1) and / or the exterior-side surface (III) of the inner pane (2), or ii) is formed as an opaque-colored region of the thermoplastic intermediate layer (3).

12. Composite pane (100) according to one of claims 1 to 11, wherein the adhesive layer (5) is a thermoplastic layer or an optically clear adhesive (OCA).

13. Projection arrangement (101) comprising at least one composite pane (100) according to one of claims 1 to 12, an imaging unit (10) directed onto the at least one reflection layer (7).

14. A method for producing a composite pane (100) according to one of claims 1 to 12, comprising a) producing a composite from an outer pane (1) with an outer surface (I) and an interior surface (II), a thermoplastic intermediate layer (3), and an inner pane (2) with an outer surface (III) and an interior surface (IV), wherein the thermoplastic intermediate layer (3) is arranged between the outer pane (1) and the inner pane (2), and at least one masking layer (4) is arranged in a region between the outer pane (1) and the inner pane (2); b) providing a glass pane (6) with an outer surface (V) and an interior surface (VI), wherein at least one reflective layer (7) for reflecting light is arranged on the outer surface (V) of the glass pane (6) and / or on the interior surface (VI) of the glass pane (6);c) connecting the glass pane (6) to the inner pane (2) via an adhesive layer (5) to form a composite pane (100), such that the glass pane (6) is arranged in a region of the composite pane (100) which, when viewed perpendicularly through the; Composite pane (100) lies entirely in the area in which the at least one masking layer (4) is arranged.

15. Use of the composite pane (100) according to one of claims 1 to 12 as a vehicle pane in means of transport for traffic on land, in the air or on water, in particular in motor vehicles and in particular as a windshield for a head-up display.

Images