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), a masking layer (4), which is arranged in a region of the composite pane (100), an adhesive layer (5), and a glass pane (6) with an exterior surface (V) and an interior surface (VI) and a thickness of 20 µm to 300 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), a reflective layer (7) for reflecting light is arranged on the exterior surface (V) of the glass pane (6) and / or on the interior surface (VI) of the glass pane (6), and the glass pane (6) is arranged in a region of the composite pane (100) which, in a perpendicular view through the composite pane (100), lies entirely in the region in which the masking layer (4) is arranged. The adhesive layer (5) is formed as an opaquely coloured adhesive layer (5a) or the adhesive layer (5) is formed as an opaquely coloured adhesive layer (5a) or a colourless adhesive layer (5b) and, between the adhesive layer (5) and the glass pane (6), an opaque layer (8) is arranged directly adjacent to the adhesive layer (5).

Description

[0001] Composite pane with a reflective layer applied in certain areas

[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 (HUDs). 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 (as seen from the driver's perspective) 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 a reflective coating to glass panes is typically carried out using physical vapor deposition (PVD), for example, by cathode sputtering, particularly by magnetic field-assisted cathode sputtering (magnetron sputtering). Cold spraying is also a suitable method for coating glass panes and is a coating process well known to those skilled in the art.

[0006] WO 2019 / 186495 A1 discloses a laminated glass with at least one stepped functional section comprising two stacks of components: the main stack of components, for which changes in their properties are not desired, and a second component stack comprising a functional layer. The functional layer can be selected from the group consisting of switchable film, switchable layers, displays, illuminants, touch-sensitive layers, sensor layers, light sensors, acoustic sensors, acoustic PVB layers, heat-reflecting films, and heat-absorbing films.

[0007] The publication "Glass meets flexibility: Challenges in manufacturing of thin films on flexible glass" by M. Junghähnel et al., published in Vakuum in Forschung und Praxis, Vol. 26, No. 5, pp. 35-39, discusses the production of thin films on flexible glass.

[0008] WO 2022 / 161894 A1 describes a vehicle window for a head-up display comprising at least one transparent pane and at least one masking strip in the edge region of the pane. The masking strip is arranged on or in a carrier film, the carrier film is bonded to the transparent pane, and a light-directing device or an image display device is arranged in the region of the first masking strip on the vehicle interior side of the masking strip. The light-directing device can, for example, be a holographic light-directing device with at least one holographic-optical element suitable for light directing, which is designed to direct incident light toward the vehicle interior.

[0009] The present invention is based on the object of providing an improved composite pane with a reflective layer applied in certain areas. In particular, the composite pane should be easy to manufacture and the occurrence of ghost images should be avoided. This object of the present invention is achieved by a composite pane according to claim 1. Preferred embodiments are set out in the subclaims.

[0010] The composite pane according to the invention comprises an outer pane, a thermoplastic intermediate layer, a 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 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 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 side and an inner side surface and a circumferential side edge running between them. For the purposes of the invention, the term outer surface refers to the main surface which is intended to face the outside environment in the installed position. For the purposes of the invention, the term inner surface refers to the main surface which is intended to face the interior in the installed position. The interior side surface of the outer pane and the outer surface of the inner pane face each other and are connected to one another by the thermoplastic intermediate layer. The outer side surface of the outer pane is referred to as side I. The interior side surface of the outer pane is referred to as side II. The outer side surface of the inner pane is referred to as side III.The interior surface of the inner pane is referred to as side IV. The exterior surface of the glass pane is referred to as side V. The interior surface of the glass pane is referred to as side VI.

[0014] It is understood that the inner pane is arranged between the outer pane and the glass pane. The interior surface of the outer pane and the exterior surface of the inner pane face each other. The interior surface of the inner pane and the exterior surface of the glass pane face each other.

[0015] According to the invention, the glass pane has a thickness of 20 pm (micrometers) to 300 pm. The glass pane is thus made of ultra-thin glass. Such a pane of ultra-thin glass is flexible and can be adapted to the curvature of a pane.

[0016] In addition, according to the invention, a 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.

[0017] When the composite pane is installed in a vehicle, the reflective layer is therefore at a shorter distance from the vehicle interior than the masking layer.

[0018] According to the invention, the adhesive layer is either formed as an opaque colored adhesive layer or the adhesive layer is formed as an opaque colored adhesive layer or a colorless adhesive layer and an opaque layer is arranged between the adhesive layer and the glass pane immediately adjacent to the adhesive layer.

[0019] In one embodiment, the adhesive layer is thus formed as an opaque colored adhesive layer, and no opaque layer is arranged between the adhesive layer and the glass pane immediately adjacent to the adhesive layer. In an alternative embodiment, the adhesive layer is formed as a colorless adhesive layer, and an opaque layer is arranged between the adhesive layer and the glass pane immediately adjacent to the adhesive layer.

[0020] In an alternative embodiment, the adhesive layer is thus formed as an opaque colored adhesive layer and an opaque layer is arranged between the adhesive layer and the glass pane immediately adjacent to the adhesive layer.

[0021] The opaque layer is preferably black. The opaque colored adhesive layer is preferably black.

[0022] Because the glass pane is arranged in an area of ​​the composite pane which, when viewed perpendicularly through the composite pane, lies entirely in the area in which the masking layer is arranged, the reflective layer applied to the glass pane is also arranged in an area which, when viewed perpendicularly through the composite pane, lies entirely in the area 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 from the inside of the composite pane.

[0023] Furthermore, because the adhesive layer is formed as an opaque-colored adhesive layer and / or an opaque layer is arranged between the adhesive layer and the glass pane directly adjacent to the adhesive layer, the reflective layer applied to the glass pane is arranged in a vertical view through the composite pane or in an orthogonal projection through the composite pane in overlap with the opaque-colored adhesive layer or the opaque layer, respectively. The reflective layer is thus only formed where it is located in front of the opaque-colored adhesive layer or the opaque layer, respectively, when viewed from the inside of the composite pane.The opaque colored adhesive layer and / or the opaque layer prevent ghost images that could occur on the interior surface of the inner pane, on the exterior surface of the inner pane, on the interior surface of the outer pane, and / or on a surface of a layer arranged between the inner pane and the outer pane. In a preferred embodiment of the composite pane according to the invention, the glass pane has a thickness of 50 μm to 200 μm, particularly preferably 50 μm to 100 μm, for example 70 μm or 100 μm.

[0024] As described above, the reflective layer is a reflective layer for reflecting light. The reflective layer is preferably opaque or partially translucent, which, within the meaning of the invention, means that it has an average transmission (according to ISO 9050:2003) in the visible spectral range of preferably at most 90%, particularly preferably at most 80%, very particularly preferably at most 50%, and in particular less than 10%. The reflective layer preferably reflects at least 10%, particularly preferably at least 25%, of the light incident on the reflective layer. This value is also referred to as the reflectance. The reflective layer preferably reflects p-polarized and s-polarized light to different degrees.

[0025] 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 degree of reflection (over different angles of incidence) with respect to p-polarized and s-polarized radiation, so that a high-intensity and color-neutral image representation is ensured.

[0026] 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.

[0027] 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.

[0028] The reflectance describes the proportion of the total incident radiation in the specified spectral range that is reflected. The reflectance always refers to a specific spectral range, for example, the visible spectral range from 380 nm to 780 nm or, for example, the ultraviolet range. It is expressed as a percentage (relative to 100% incident radiation) or as a unitless number from 0 to 1 (normalized to the incident radiation). Plotted as a function of wavelength, it forms the reflection spectrum. The information on the reflectance or reflection spectrum refers to a reflection measurement with a light source that radiates uniformly in the spectral range under consideration with a normalized radiation intensity of 100%.

[0029] The term "reflectance" is used in accordance with the DIN EN 410 - 2011-04 standard. Reflectance always refers to the coating-side reflectance, which is measured when the substrate with the coated areas—here, the glass pane arranged on the inner pane—is facing the light source and the detector. Transparent elements, such as the glass pane, may be interposed to separate the coated substrate from the light source and the detector.

[0030] The reflectance is measured at an angle of incidence of 8° (unless otherwise stated) to the coated surface normal. The spectral range from 380 nm to 800 nm was used to characterize the reflection properties.

[0031] In a preferred embodiment of the invention, the reflective layer contains or consists of a dielectric layer and / or a metallic layer. In a particularly preferred embodiment, the reflective layer is a metallic layer. In a further preferred embodiment, the reflective layer is a dielectric layer.

[0032] In a particularly preferred embodiment, the reflective layer is a layer stack comprising a metallic layer and a dielectric layer, with the dielectric layer preferably being located behind the metallic layer when viewed from the inside of the composite pane. A reflective layer formed as a layer stack comprising a metallic layer and a dielectric layer has a higher reflectivity to visible light than a reflective layer formed as a dielectric layer or metallic layer.

[0033] The dielectric layer may be a single-layer or a multi-layer layer and may comprise or consist of at least one high-index layer with a refractive index greater than 1.9.

[0034] Preferably, the high-index layer is formed on the basis of silicon nitride, tin-zinc oxide, silicon zirconium nitride, silicon aluminum nitride, silicon titanium nitride, silicon hafnium nitride, or titanium oxide, with titanium oxide being particularly preferred.

[0035] The dielectric layer preferably has a thickness of 1 nm (nanometers) to 120 nm, particularly preferably from 40 nm to 80 nm, most preferably from 50 nm to 70 nm.

[0036] The metallic layer preferably contains or consists of at least one metal selected from a group consisting of zirconium, hafnium, silver, gold, nickel, chromium, molybdenum, tungsten, copper, vanadium, niobium, tantalum, palladium, platinum, titanium, zinc, tin or aluminum or alloys thereof.

[0037] The metallic layer preferably has a thickness of 1 nm to 100 nm, particularly preferably of 5 nm to 50 nm, in particular of 8 nm to 15 nm.

[0038] Methods for measuring the thickness of the dielectric layer and the thickness of the metallic layer are known to those skilled in the art. The thicknesses can be determined using common methods for determining the thickness of thin films, for example, spectroscopic reflectometry, confocal microscopy, white light interferometry, or ellipsometry. These methods enable non-destructive measurement, and corresponding measuring instruments are commercially available. Ellipsometers are commercially available, for example, from Sentech. White light interferometry, profilometry, for example, confocal profilometry, or ellipsometry are preferred.

[0039] In a particularly preferred embodiment of the composite pane according to the invention, the reflective layer for reflecting light is arranged on the outer surface of the glass pane. Thus, in this embodiment, no reflective layer is arranged on the inner surface of the glass pane. This embodiment offers, among other advantages, that a reflective layer arranged in this way is bonded to the inner pane via the adhesive layer, or an opaque layer is arranged on a reflective layer arranged in this way, thus protecting the reflective layer.

[0040] In a preferred embodiment of the composite pane according to the invention, a reflective layer for reflecting light is arranged on the interior surface of the glass pane, and a protective layer is preferably arranged on this reflective layer. Thus, in this embodiment, no reflective layer is arranged on the exterior surface of the glass pane.

[0041] 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 preferably 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 connected to the inner pane via the adhesive layer, or an opaque layer is arranged on this reflective layer, thus protecting this reflective layer. Optionally, however, a protective layer can also be arranged on a reflective layer arranged on the exterior surface of the glass pane.

[0042] 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.

[0043] 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. With the protective layer, fewer particles separate from the reflective layer over time, and the reflective layer retains its shape for longer. In a particularly preferred embodiment of the invention, the protective layer is an easy-to-clean layer and / or an "anti-fingerprint" layer. By "easy-to-clean layer" is meant, within the meaning of the invention, 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 based on alcohols, are therefore largely avoided for cleaning the protective layer.For the purposes of the invention, an "anti-fingerprint" layer refers to a layer where fingerprints adhering to the protective layer are barely or not at all visually perceptible. Fingerprints refer, in particular, to the fatty components of a human finger that can remain on a surface when touching it and can have an unsightly effect.

[0044] As described above, in the composite pane according to the invention, a 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.

[0045] 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.

[0046] In a particularly preferred 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 a greater width, in particular in a section that overlaps the glass pane, than in sections different therefrom.

[0047] 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.

[0048] The masking layer, within the meaning of the invention, is a layer that prevents visibility through the composite pane. The masking layer transmits a maximum of 5%, preferably a maximum of 2%, particularly preferably a maximum of 1%, in particular a maximum of 0.1%, of light of the visible spectrum. The masking layer is thus an opaque masking layer, preferably a black masking layer.

[0049] The masking layer is preferably a coating consisting of 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.

[0050] The masking layer is in particular an opaque cover print made of a dark, preferably black, enamel.

[0051] In a preferred embodiment, the masking layer is formed as an opaque cover print arranged on the interior-side surface of the outer pane, in particular made of a dark, preferably black, enamel.

[0052] In an alternative preferred embodiment, the masking layer is formed as an opaque cover print arranged on the outer surface of the inner pane, in particular made of a dark, preferably black, enamel. In an alternative preferred embodiment, the masking layer is formed as an opaque-colored region of the thermoplastic intermediate layer.

[0053] In one embodiment, the thermoplastic intermediate layer is formed in one piece and is colored opaque in one area.

[0054] 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.

[0055] The composite pane according to the invention can additionally have an additional 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 an additional masking print on the interior-side surface of the inner pane improves the adhesion properties of the surface to an adhesive layer. The additional opaque masking print is preferably frame-shaped.

[0056] The adhesive layer is preferably a thermoplastic layer or an adhesive. As described above, the adhesive layer is formed as an opaque-colored adhesive layer if no opaque layer is arranged between the adhesive layer and the glass pane immediately adjacent to the adhesive layer, and the adhesive layer is formed as an opaque-colored or colorless adhesive layer if an opaque layer is arranged between the adhesive layer and the glass pane immediately adjacent to the adhesive layer.

[0057] An opaque colored adhesive layer can thus preferably be formed as an opaque colored thermoplastic layer or an opaque colored adhesive and a colorless adhesive layer can preferably be formed as a colorless thermoplastic layer or an optically clear adhesive.

[0058] Suitable opaque colored adhesives and suitable optically clear adhesives, so-called optical clear adhesives (OCA), are known to those skilled in the art.

[0059] A colorless 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. A thermoplastic layer formed as an opaque-colored thermoplastic layer additionally contains pigments.

[0060] Suitable opaque colored thermoplastic layers are known to the person skilled in the art.

[0061] The opaque layer can be formed as an opaque coating arranged directly or indirectly on the outside surface of the glass pane. In embodiments in which the composite pane has an opaque layer and the reflective layer is arranged only on the inside surface of the glass pane, the opaque layer is formed as a coating arranged directly on the outside surface of the glass pane. In embodiments in which the composite pane has an opaque layer and a reflective layer is arranged on the outside surface of the glass pane, the opaque layer is formed as a coating on the reflective layer arranged on the outside surface of the glass pane, i.e., in these embodiments, the opaque layer is formed as a coating arranged indirectly on the outside surface of the glass pane.

[0062] An opaque adhesive layer within the meaning of the invention is an adhesive layer that prevents visibility through the composite pane. The opaque adhesive layer transmits 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 through the opaque layer. An opaque layer within the meaning of the invention is a layer that prevents visibility through the composite pane. The opaque layer transmits 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 through the opaque layer.

[0063] In one embodiment, the composite pane additionally comprises a HUD layer arranged between the outer pane and the inner pane.

[0064] The principle of a head-up display (HUD) and the technical terms used in the field of HUDs are generally known to those skilled in the art. For a detailed description, please refer to the dissertation "Simulation-based Measurement Technology for Testing Head-Up Displays" by Alexander Neumann at the Institute of Computer Science at the Technical University of Munich (Munich: University Library of the TU Munich, 2012), particularly Chapter 2, "The Head-Up Display." The HUD layer is arranged between the outer pane and the inner pane, where "between" can mean both within the thermoplastic intermediate layer and in direct spatial contact with the interior surface of the outer pane and the exterior surface of the inner pane. The HUD layer is designed to reflect p-polarized light.The HUD layer is a reflective coating applied over a large area of ​​the composite pane. The area containing the HUD coating is also referred to as the HUD area. To use the composite pane as a head-up display, a projector is directed at the HUD area of ​​the composite pane. The projector's radiation is preferably predominantly p-polarized. The HUD layer is designed to reflect p-polarized radiation. This creates a virtual image from the projector radiation, which the driver of a vehicle can perceive from behind the composite pane.

[0065] The HUD layer preferably comprises at least one metal selected from the group consisting of aluminum, tin, titanium, copper, chromium, cobalt, iron, manganese, zirconium, cerium, yttrium, silver, gold, platinum, and palladium, or mixtures thereof. In a preferred embodiment, the HUD layer is a coating containing a thin-film stack, i.e., a sequence of thin individual layers. This thin-film stack contains one or more electrically conductive layers based on silver. The electrically conductive layer based on silver imparts the basic reflective properties to the HUD layer, as well as an IR-reflecting effect and electrical conductivity. The conductive layer preferably contains at least 90 wt.% silver, more preferably at least 99 wt.% silver, most preferably at least 99.9 wt.% silver. The silver layer may contain dopants, for example, palladium, gold, copper, or aluminum.Silver-based materials are particularly suitable for reflecting p-polarized light. The HUD layer has a thickness of 5 nm to 50 nm, and preferably 8 nm to 25 nm.

[0066] The HUD layer can also be formed as a reflective film that reflects p-polarized light. The HUD layer can be a carrier film with a reflective coating or a reflective polymer film. The reflective coating preferably comprises at least one metal-based layer and / or a dielectric layer sequence with alternating refractive indices. The metal-based layer preferably contains or consists of silver and / or aluminum. The dielectric layers can be formed, for example, from silicon nitride, zinc oxide, tin-zinc oxide, silicon-metal mixed nitrides such as silicon zirconium nitride, zirconium oxide, niobium oxide, hafnium oxide, tantalum oxide, or silicon carbide. The aforementioned oxides and nitrides can be deposited stoichiometrically, substoichiometrically, or superstoichiometrically. They can contain dopants, for example, aluminum, zirconium, titanium, or boron.The reflective polymer film preferably comprises or consists of dielectric polymer layers. The dielectric polymer layers preferably contain PET. If the HUD layer is formed as a reflective film, it is preferably 30 μm to 300 μm thick, particularly preferably 50 μm to 200 μm thick, and especially 100 μm to 150 μm thick. According to a further preferred embodiment, the HUD layer is formed as a reflective film and arranged within the thermoplastic intermediate layer.

[0067] The composite pane is preferably curved in one or more directions, as is common for automotive windows, with typical radii of curvature ranging from approximately 10 cm to approximately 40 m. However, the composite pane can also be flat, for example, if it is intended for use as a pane for buses, trains, or tractors.

[0068] 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 pm. The thermoplastic intermediate layer can be formed by a single film or by more than one film. The thermoplastic intermediate layer can also be a film with functional properties, for example a film with acoustically dampening properties.

[0069] 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.

[0070] 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.

[0071] 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, and 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 thin glass with a thickness of, for example, 0.55 mm.

[0072] The glass pane preferably contains or consists of aluminosilicate glass, borosilicate glass, or aluminoborosilicate glass. The glass pane may be untempered, partially tempered, or prestressed. The composite pane according to the invention may comprise one or more additional intermediate layers, in particular functional intermediate layers, between the outer pane and the inner pane. An additional intermediate layer may, in particular, be an intermediate layer with acoustically dampening properties, an intermediate layer that reflects infrared radiation, an intermediate layer that absorbs infrared radiation, a UV-radiation-absorbing intermediate layer, an intermediate layer that is colored at least in sections, and / or an intermediate layer that is tinted at least in sections. If several additional intermediate layers are present, these can also have different functions.

[0073] In the context of the present invention, refractive indices are generally specified relative to a wavelength of 550 nm. Unless otherwise stated, the specification of layer thicknesses refers to the geometric thickness of a layer.

[0074] The invention also relates to a projection arrangement comprising at least one composite pane according to the invention and an imaging unit directed onto the reflection layer.

[0075] According to the invention, a projection arrangement is thus also provided at least comprising a composite pane, at least 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, a masking layer 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 300 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 which, when viewed perpendicularly through the composite pane, lies entirely within the region in which the masking layer is arranged, and wherein the adhesive layer is formed as an opaque colored adhesive layer, or the adhesive layer is formed as an opaque colored adhesive layer or a colorless adhesive layer, and an opaque layer is arranged between the adhesive layer and the glass pane immediately adjacent to the adhesive layer. and an imaging unit directed toward the reflective layer.

[0076] Preferably, a reflective layer is arranged only on the outer surface of the glass pane.

[0077] In particular, the combination of the reflective layer with the masking layer behind it from the perspective of a vehicle occupant and the opaque colored adhesive layer and / or opaque layer 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.

[0078] From the perspective of a vehicle occupant, the reflective layer is arranged spatially in front of the masking layer and spatially in front of the opaque adhesive layer and / or the opaque layer when viewed through the inner pane. The area of ​​the composite pane in which the reflective layer is arranged therefore appears opaque. The expression “when viewed through the composite pane” means that the view through the composite pane is from the interior. For the purposes of the present invention, “spatially in front” means that the reflective layer is arranged spatially further away from the outer surface of the outer pane than the masking layer and spatially further away from the outer surface of the outer pane than the opaque adhesive layer and / or the opaque layer.Preferably, the masking layer is a peripheral masking layer and is widened at least in the region that overlaps with the reflective layer and in which the composite pane is used to display images. This means that the masking layer has a greater width in this region, viewed perpendicular to the nearest section of the peripheral edge of the composite pane, than in other sections. The masking layer can thus be adapted to the dimensions of the reflective layer. The imaging unit of the projection arrangement emits light and is arranged adjacent to the interior-side surface of the composite pane such that the imaging unit irradiates this surface, the light being reflected by the reflective layer of the composite pane.The reflective layer preferably reflects at least 10%, particularly preferably at least 25%, of the light incident on the reflective layer in a wavelength range of 400 nm to 700 nm and at angles of incidence of 55° to 80°. This is advantageous for achieving the greatest possible brightness of an image emitted by the imaging unit and reflected by the reflective layer.

[0079] 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.

[0080] 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.

[0081] 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. 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 created by reflection from the reflective layer applied to the outside surface of the glass pane, and in addition, a second virtual image is created by the reflective layer applied to the inside surface of the glass pane.

[0082] However, with the thin glass pane thicknesses used in 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 to be undesirable. This effect is based on the typical angular acuity of the human eye: the thin glass pane used in the invention leads to an offset between the first virtual image and the ghost image, or between the first virtual image and the second virtual image, that is no longer resolvable to the human eye.

[0083] In preferred embodiments of the projection arrangement according to the invention, the imaging unit emits s-polarized radiation and p-polarized radiation in a ratio between 1:10 and 10:1 or the imaging unit emits circularly polarized radiation.

[0084] In one embodiment, the imaging unit comprises a λ / 2 retardation plate, by means of which the ratio of s-polarized radiation and p-polarized radiation emitted by the imaging unit onto the reflective layer can be varied. For example, the proportion of p-polarized radiation can be increased if the driver wears polarization-selective sunglasses, and the proportion of s-polarized radiation can be increased if the driver does not wear polarization-selective sunglasses.

[0085] The projection arrangement according to the invention is particularly suitable for combination with a HUD layer. In this case, the composite pane has a HUD layer, as described above in one embodiment of the composite pane according to the invention, which is arranged between the outer pane and the inner pane. The masking layer and thus also the glass pane with the reflective layer and the opaque-colored adhesive layer or the opaque layer are, in this embodiment, only locally limited to the edge region of the composite pane and therefore do not influence the HUD layer applied in the view-through region of the composite pane. The preferred embodiments of the composite pane according to the invention described above also apply accordingly to the projection arrangement according to the invention comprising a composite pane according to the invention and an imaging unit, and vice versa.

[0086] The invention also relates to a method for producing a composite pane according to the invention, at least comprising: a) providing a composite of 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 a 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 and a thickness of 20 μm to 300 μm, 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) connecting the glass pane to the inner pane of the composite 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, wherein the adhesive layer is designed as an opaque colored adhesive layer or the adhesive layer is designed as an opaque colored adhesive layer or a colorless adhesive layer and an opaque layer is arranged between the adhesive layer and the glass pane immediately adjacent to the adhesive layer;

[0087] Steps a) and b) can be performed in the specified order, simultaneously, or in reverse order. Step c) is performed after steps a) and b).

[0088] It is understood that the external dimensions, i.e., the length and width, of the adhesive layer correspond to the external dimensions of the glass pane. As explained above, the glass pane is arranged in a region of the laminated pane that, when viewed perpendicularly through the laminated pane, lies entirely within the area where the masking layer is arranged. Thus, the external dimensions of the glass pane are smaller than the outer and inner panes of the laminated pane.

[0089] The glass pane can be provided in step b) by applying a reflective layer over the entire surface of the interior and / or exterior surface of an uncoated glass pane with the desired dimensions. To produce embodiments of composite panes according to the invention in which an opaque layer is arranged between the adhesive layer and the glass pane, immediately adjacent to the adhesive layer, in step b) an opaque layer is applied over the entire surface of the exterior surface of the glass pane or, if a reflective layer is applied to the exterior surface of the glass pane, over the entire surface of the reflective layer applied to the exterior surface of the glass pane.

[0090] Alternatively, the provision of the glass pane in step b) can also be carried out by applying a reflective layer over the entire surface of the interior side and / or the exterior side of an uncoated glass pane which is larger than desired in terms of external dimensions, i.e. width and length, 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.To produce embodiments of composite panes according to the invention in which an opaque layer is arranged between the adhesive layer and the glass pane immediately adjacent to the adhesive layer, in step b) an opaque layer is additionally applied over the entire surface of the outer side of the glass pane or, if a reflective layer is applied to the outer side of the glass pane, over the entire surface of the reflective layer applied to the outer side of the glass pane.

[0091] A reflective layer can be selectively arranged in an area of ​​the composite pane over the glass pane provided with the reflective layer.

[0092] The provision of the glass pane in step b) may additionally comprise the application of a protective layer to the reflective layer applied to the interior surface. The protective layer is preferably applied to the reflective layer by spraying or squirting, for example, using a pressure atomizer.

[0093] If the composite pane is to be curved, a curved outer pane and a curved inner pane are used during the preparation of the composite in step a). The glass pane with the reflective coating is flexible due to its thinness and adapts to the curved inner pane of the composite 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.

[0094] The composite in step a) can be provided by means of lamination processes familiar to the person skilled in the art.

[0095] When providing 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.

[0096] The application of an opaque layer can be done, for example, by spray coating.

[0097] The preferred embodiments of the composite pane according to the invention described above also apply accordingly to methods for producing a composite pane according to the invention.

[0098] 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.

[0099] The invention is explained in more detail below with reference to drawings and exemplary embodiments. The drawings are schematic representations and not to scale. The drawings do not limit the invention in any way. They show:

[0100] Fig. 1 is a plan view of an embodiment of an inventive

[0101] composite pane,

[0102] Fig. 2 is a cross-section through the embodiment shown in Fig. 1,

[0103] Fig. 3 shows a cross section through a further embodiment of an inventive

[0104] composite pane,

[0105] Fig. 4 shows a cross section through a further embodiment of an inventive

[0106] composite pane,

[0107] Fig. 5 shows a cross section through a further embodiment of an inventive

[0108] composite pane,

[0109] Fig. 6 shows a cross section through a further embodiment of an inventive

[0110] composite pane,

[0111] Fig. 7 shows a cross section through a further embodiment of an inventive

[0112] composite pane,

[0113] Fig. 8 shows a cross section through a further embodiment of an inventive

[0114] composite pane,

[0115] Fig. 9 shows a cross section through a further embodiment of an inventive

[0116] composite pane,

[0117] Fig. 10 shows a cross section through a further embodiment of an inventive

[0118] composite pane,

[0119] Fig. 11 shows a cross section through a further embodiment of an inventive

[0120] composite pane,

[0121] Fig. 12 shows a cross section through a further embodiment of an inventive

[0122] composite pane,

[0123] Fig. 13 shows a cross section through a further embodiment of an inventive

[0124] composite pane,

[0125] Fig. 14 shows a cross section through a further embodiment of an inventive

[0126] composite pane,

[0127] Fig. 15 shows a cross section through a further embodiment of an inventive

[0128] composite pane,

[0129] Fig. 16 shows a cross section through a further embodiment of an inventive

[0130] composite pane,

[0131] Fig. 17 shows a cross section through an embodiment of an inventive

[0132] Projection arrangement, Fig. 18 a plan view of a further embodiment of a composite pane according to the invention,

[0133] Fig. 19 is a cross-section through the embodiment shown in Fig. 18,

[0134] Fig. 20 a cross-section through a coated glass pane,

[0135] Fig. 21 a cross-section through another coated glass pane,

[0136] Fig. 22 a cross-section through another coated glass pane,

[0137] Fig. 23 shows an embodiment of a method according to the invention using a flow chart,

[0138] Fig. 24 Reflection spectra of an embodiment of a composite pane according to the invention,

[0139] Fig. 25 Reflection spectra of another embodiment of an inventive

[0140] Composite pane, and

[0141] Fig. 26 Reflection spectra of another embodiment of an inventive

[0142] Composite pane.

[0143] Fig. 1 shows a plan view of an embodiment of an inventive

[0144] Composite pane 100 and in Fig. 2 is the cross section through the pane shown in Fig. 1

[0145] Composite pane 100 shown along section line XX'. The composite pane 100 shown in Figs. 1 and 2 has an upper edge O, a lower edge U and two side edges S and 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 with 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. In the embodiment shown in Figs. 1 and 2, the masking layer 4 is formed as an 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. In the embodiment shown in Fig. 2, a reflective layer 7 for reflecting light is arranged on the outer surface V of the glass pane 6.The outer surface V of the glass pane 6 with the reflective layer 7 arranged thereon is connected to the inner surface IV of the inner pane 2 via the adhesive layer 5.

[0146] The glass pane 6 is made, for example, of aluminosilicate glass and has a thickness of 100 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.

[0147] In the embodiment shown in Fig. 2, the adhesive layer 5 is formed as an opaque colored adhesive layer 5a and is, for example, an opaque colored adhesive.

[0148] The reflection layer 7 is, for example, a titanium dioxide layer with a thickness of 67 nm or a nickel-chromium layer with a thickness of 10 nm or a nickel-chromium layer with a thickness of 10 nm to which a titanium dioxide layer with a thickness of 67 nm is applied.

[0149] In the embodiment shown in Figs. 1 and 2, the masking layer 4 extends between the two side edges S of the composite pane 100 and has, for example, a width of 30 cm starting from the lower edge U of the composite pane 100.

[0150] 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.

[0151] Fig. 3 shows a cross-section through a further embodiment of a composite pane 100 according to the invention. The embodiment shown in cross-section in Fig. 3 differs from that shown in Fig. 2 only in that the masking layer 4 is not designed as an opaque cover print arranged on the interior-side surface II of the outer pane 1, but rather as an opaque cover print arranged on the exterior-side surface III of the inner pane 2. Fig. 4 shows a cross-section through a further embodiment of a composite pane 100 according to the invention. The embodiment shown in cross-section in Fig. 4 differs from that shown in Fig. 2 only in that the masking layer 4 is not designed as an opaque cover print arranged on the interior-side surface II of the outer pane 1, but rather as an opaque-colored region of the thermoplastic intermediate layer 3.

[0152] Fig. 5 shows a cross-section through another embodiment of a composite pane 100 according to the invention. The embodiment shown in cross-section in Fig. 5 differs from that shown in Fig. 2 only in that the adhesive layer 5 is formed as a colorless adhesive layer 5b, and an opaque layer 8 is arranged between the glass pane 6 and the adhesive layer 5, immediately adjacent to the adhesive layer 5. The adhesive layer 5 formed as a colorless adhesive layer 5b is, for example, an optically clear adhesive.

[0153] Fig. 6 shows a cross section through a further embodiment of a composite pane 100 according to the invention. The embodiment shown in cross section in Fig. 6 differs from that shown in Fig. 5 only in that the masking layer 4 is not formed as an opaque cover print arranged on the interior-side surface II of the outer pane 1, but is formed as an opaque cover print arranged on the exterior-side surface III of the inner pane 2.

[0154] Fig. 7 shows a cross section through a further embodiment of a composite pane 100 according to the invention. The embodiment shown in cross section in Fig. 7 differs from that shown in Fig. 5 only in that the masking layer 4 is not formed as an opaque cover print arranged on the interior-side surface II of the outer pane 1, but is formed as an opaque colored region of the thermoplastic intermediate layer 3

[0155] Fig. 8 shows a cross-section through a further embodiment of a composite pane 100 according to the invention. The embodiment shown in cross-section in Fig. 8 differs from that shown in Fig. 2 only in that the reflective layer 7 is not arranged on the outer surface V of the glass pane 6, but on the inner surface VI of the glass pane 6. In the embodiment shown in Fig. 8, the outer surface V of the glass pane 6 is thus directly connected to the inner surface IV of the inner pane 2 via the adhesive layer 5.

[0156] Fig. 9 shows a cross section through a further embodiment of a composite pane 100 according to the invention. The embodiment shown in cross section in Fig. 9 differs from that shown in Fig. 8 only in that the masking layer 4 is not formed as an opaque cover print arranged on the interior-side surface II of the outer pane 1, but is formed as an opaque cover print arranged on the outside surface III of the inner pane 2.

[0157] Fig. 10 shows a cross section through a further embodiment of a composite pane 100 according to the invention. The embodiment shown in cross section in Fig. 10 differs from that shown in Fig. 8 only in that the masking layer 4 is not formed as an opaque cover print arranged on the interior-side surface II of the outer pane 1, but is formed as an opaque colored region of the thermoplastic intermediate layer 3.

[0158] Fig. 11 shows a cross-section through another embodiment of a composite pane 100 according to the invention. The embodiment shown in cross-section in Fig. 11 differs from that shown in Fig. 8 only in that the adhesive layer 5 is formed as a colorless adhesive layer 5b, and an opaque layer 8 is arranged between the glass pane 6 and the adhesive layer 5, immediately adjacent to the adhesive layer 5. The adhesive layer 5 formed as a colorless adhesive layer 5b is, for example, an optically clear adhesive.

[0159] Fig. 12 shows a cross section through a further embodiment of a composite pane 100 according to the invention. The embodiment shown in cross section in Fig. 12 differs from that shown in Fig. 11 only in that the masking layer 4 is not formed as an opaque cover print arranged on the interior-side surface II of the outer pane 1, but is formed as an opaque cover print arranged on the exterior-side surface III of the inner pane 2.

[0160] Fig. 13 shows a cross section through a further embodiment of a composite pane 100 according to the invention. The embodiment shown in cross section in Fig. 13 differs from that shown in Fig. 11 only in that the masking layer 4 is not formed as an opaque cover print arranged on the interior-side surface II of the outer pane 1, but is formed as an opaque colored region of the thermoplastic intermediate layer 3.

[0161] Fig. 14 shows a cross section through a further embodiment of a composite pane 100 according to the invention. The embodiment shown in cross section in Fig. 14 differs from that shown in Fig. 5 only in that the adhesive layer 5 is formed as an opaque colored adhesive layer 5a.

[0162] It is understood that the embodiments shown in Figs. 6, 7, 11, 12 and 13 can also be modified such that the adhesive layer 5 is formed as an opaque colored adhesive layer 5a instead of as a colorless adhesive layer 5b.

[0163] Fig. 15 shows a cross-section through another embodiment of a composite pane 100 according to the invention. The embodiment shown in cross-section in Fig. 15 differs from the one shown in Fig. 8 only in that a protective layer 9 is additionally applied to the reflective layer 7 applied to the interior-side surface VI of the glass pane 6. The protective layer 9 is, for example, a polymer based on polyacrylates, polyoximes, alkyd resins, polyurethanes, or mixtures thereof. The protective layer 9 has, for example, a thickness of 500 nm.

[0164] It is understood that the embodiments shown in Figs. 9 to 13 can also be modified in such a way that a protective layer 9 is additionally applied to the reflection layer 7 applied to the interior-side surface VI of the glass pane 6.

[0165] Fig. 16 shows a cross-section through a further embodiment of a composite pane 100 according to the invention. The embodiment shown in cross-section in Fig. 16 differs from that shown in Fig. 2 only in that a reflective layer 7 is additionally applied to the interior-side surface VI of the glass pane 6. The reflective layer 7 applied to the interior-side surface VI of the glass pane 6 can be constructed identically to or differently from the reflective layer 7 applied to the exterior surface V of the glass pane 6. Optionally, a protective layer 9 can be arranged on the reflective layer 7 applied to the interior-side surface VI of the glass pane 6 in the direction of the vehicle interior.

[0166] It is understood that the embodiments shown in Figs. 3 to 7 and 14 can also be modified in such a way that a reflective layer 7 is additionally applied to the interior-side surface VI of the glass pane 6, on which reflective layer 7 a protective layer 9 is optionally arranged.

[0167] Fig. 17 shows a cross-section through an embodiment of a projection arrangement 101 according to the invention. The projection arrangement 101 shown in Fig. 16 comprises a composite pane 100 and an imaging unit 10.

[0168] The composite pane 100 is designed as shown in Fig. 2 and comprises an outer pane 1 with an outer surface I and an inner surface II, an inner pane 2 with an outer surface III and an inner surface IV, a thermoplastic intermediate layer 3, a masking layer 4, an adhesive layer 5 and a glass pane 6 with an outer surface V and an inner 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 with 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. The masking layer 4 is designed as an 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. 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. In the embodiment shown in Fig. 17, a reflective layer 7 for reflecting light is arranged on the outer surface V of the glass pane 6.The outer surface V of the glass pane 6 with the reflective layer 7 arranged thereon is connected to the interior surface IV of the inner pane 2 via the adhesive layer 5. The glass pane 6 consists, for example, of alumino-silicate 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 consists, for example, of soda-lime glass and is 2.1 mm thick. The inner pane 2 consists, for example, of soda-lime glass and is 1.6 mm thick.

[0169] In the embodiment shown in Fig. 17, the adhesive layer 5 is formed as an opaque colored adhesive layer 5a and is, for example, an opaque colored adhesive.

[0170] The reflection layer 7 is, for example, a titanium dioxide layer with a thickness of 67 nm or a nickel-chromium layer with a thickness of 10 nm or a nickel-chromium layer with a thickness of 10 nm to which a titanium dioxide layer with a thickness of 67 nm is applied.

[0171] For example, the laminated pane 100 is the windshield of a motor vehicle.

[0172] The projection arrangement 101 has an imaging unit 10. The imaging unit 10 is used to generate p-polarized light and s-polarized light (image information) or to generate circularly polarized light, which is directed onto the reflective layer 7 and 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, i.e. an image formed by the light, the imaging unit. 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. The imaging unit 10 preferably emits s-polarized radiation and p-polarized radiation in a ratio between 1:10 and 10:1 to each other.Optionally, the imaging unit 10 can have a λ / 2 retardation plate, by means of which the ratio of the s-polarized radiation and p-polarized radiation emitted by the imaging unit 10 can be varied. For example, the ratio can be varied depending on whether the driver is wearing polarization-selective sunglasses or not. Fig. 18 shows a plan view of another embodiment of a composite pane 100 according to the invention, and Fig. 19 shows the cross-section through the composite pane 100 shown in Fig. 18 along the section line Y'-Y. The composite panes shown in Figs.The composite pane 100 shown in Figures 18 and 19 has an upper edge O, a lower edge U and two side edges S and 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 with 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. The region in which the masking layer 4 is arranged is provided with the reference symbol A. In the embodiment shown in Figs. 18 and 19, the masking layer 4 is designed as an opaque cover print arranged on the interior-side surface II of the outer pane 1 and is arranged in a circumferential edge region which has a greater width in a section that overlaps the reflective layer 7 than in sections that differ therefrom. For simplified illustration, the masking layer is not black in Fig. 18, but rather shown patterned. 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 and in Fig.18 is provided with the reference symbol B. The glass pane 6 is thus smaller in terms of external dimensions than the inner pane 2. In the embodiment shown in Fig. 19, a reflective layer 7 for reflecting light is arranged on the outer surface V of the glass pane 6. The outer surface V of the glass pane 6, with the reflective layer 7 arranged thereon, is connected to the interior surface IV of the inner pane 2 via the adhesive layer 5.

[0173] 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.

[0174] In the embodiment shown in Fig. 19, the adhesive layer 5 is formed as an opaque colored adhesive layer 5a and is, for example, an opaque colored adhesive. The reflective layer 7 is, for example, a titanium dioxide layer with a thickness of 67 nm or a nickel-chromium layer with a thickness of 10 nm or a nickel-chromium layer with a thickness of 10 nm, onto which a titanium dioxide layer with a thickness of 67 nm is applied.

[0175] 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.

[0176] Fig. 20 shows a cross-section of an embodiment of a coated glass pane 6. In the embodiment shown in Fig. 20, a reflective layer 7 in the form of a dielectric layer 7a is applied to the outer surface V of the glass pane 6. It is understood that, alternatively or additionally, a reflective layer 7 can also be applied to the inner surface VI of the glass pane 6.

[0177] Fig. 21 shows a cross-section of an embodiment of a coated glass pane 6. In the embodiment shown in Fig. 21, a reflective layer 7 in the form of a metallic layer 7b is applied to the outer surface V of the glass pane 6. It is understood that, alternatively or additionally, a reflective layer 7 can also be applied to the inner surface VI of the glass pane 6.

[0178] Fig. 22 shows a cross-section of an embodiment of a coated glass pane 6. In the embodiment shown in Fig. 22, a reflective layer 7 in the form of a metallic layer 7b with a dielectric layer 7a applied thereto is applied to the outer surface V of the glass pane 6. It is understood that, alternatively or additionally, a reflective layer 7 can also be applied to the inner surface VI of the glass pane 6.

[0179] In embodiments in which a reflection layer 7 is applied to the glass pane 6 both on the outside surface V and on the inside surface VI, the two reflection layers 7 can be of the same or different design.

[0180] In Fig. 23, an embodiment of a method according to the invention is shown using a flow chart.

[0181] In a first step S1, a composite is provided comprising 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.

[0182] In a second step S2, a glass pane 6 having an outside surface V and an inside surface VI and a thickness of 20 pm to 300 pm is provided, wherein a reflection layer 7 for reflecting light is arranged on the outside surface V of the glass pane 6 and / or on the inside surface VI of the glass pane 6.

[0183] In a third step S3, the glass pane 6 is joined 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, and wherein the adhesive layer 5 is designed as an opaque colored adhesive layer 5a or the adhesive layer 5 is designed as an opaque colored adhesive layer 5a or a colorless adhesive layer 5b, and an opaque layer 8 is arranged between the adhesive layer 5 and the glass pane 6 directly adjacent to the adhesive layer 5.

[0184] Steps S1 and S2 can also be performed in reverse order or simultaneously.

[0185] The invention is explained below using examples. The reflection properties of various embodiments of composite panes according to the invention for p-polarized light and for s-polarized light at an angle of incidence of 60° and at an angle of incidence of 70° are compared below.

[0186] The layer sequence and the layer thickness according to Examples 1, 2 and 3 are given in Tables 1, 2 and 3. In order to simulate a masking layer 4, a dark outer pane 1 and dark PVB as a thermoplastic intermediate layer 3 were used in the examples.

[0187] Table 1

[0188] Table 2 Table 3

[0189] The reflectance describes the proportion of the total incident radiation that is reflected. It is expressed as a unitless number from 0 to 1 (normalized to the incident radiation). Plotted as a function of wavelength, it forms the reflection spectrum. The reflectance data refer to a reflection measurement with a light source of illuminant type A, which radiates in the spectral range from 380 nm to 800 nm with a normalized radiation intensity of 1.

[0190] Fig. 24 shows reflection spectra of an embodiment of a composite pane 100 which is constructed as indicated in Table 1. The reflection spectrum C shows the reflectance of the composite pane 100 with respect to s-polarized radiation irradiated at an angle of incidence of 60° as a function of the wavelength in the spectral range from 380 nm to 800 nm. The reflection spectrum D shows the reflectance of the composite pane 100 with respect to s-polarized radiation irradiated at an angle of incidence of 70° as a function of the wavelength in the spectral range from 380 nm to 800 nm. The reflection spectrum E shows the reflectance of the composite pane 100 with respect to p-polarized radiation irradiated at an angle of incidence of 60° as a function of the wavelength in the spectral range from 380 nm to 800 nm.The reflection spectrum F shows the reflectance of the composite pane 100 with respect to p-polarized radiation irradiated at an angle of incidence of 70° as a function of the wavelength in the spectral range from 380 nm to 800 nm.

[0191] Fig. 24 shows that the reflectance of a composite pane 100 with the structure shown in Table 1 with respect to s-polarized radiation is on average 0.41 and is thus approximately four times higher than the average reflectance with respect to p-polarized radiation, which is on average 0.10. If the composite pane 100 with the structure shown in Table 1 is irradiated with a mixture of s-polarized radiation and p-polarized radiation in a ratio of 1 to 1, this results in an average reflectance of 0.26 in the range from 380 nm to 800 nm.

[0192] Fig. 25 shows reflection spectra of an embodiment of a composite pane 100 according to the invention, which is constructed as indicated in Table 2. The reflection spectrum G shows the reflectance of the composite pane 100 with respect to s-polarized radiation irradiated at an angle of incidence of 60° as a function of the wavelength in the spectral range from 380 nm to 800 nm. The reflection spectrum H shows the reflectance of the composite pane 100 with respect to s-polarized radiation irradiated at an angle of incidence of 70° as a function of the wavelength in the spectral range from 380 nm to 800 nm. The reflection spectrum J shows the reflectance of the composite pane 100 with respect to p-polarized radiation irradiated at an angle of incidence of 60° as a function of the wavelength in the spectral range from 380 nm to 800 nm.The reflection spectrum K shows the reflectance of the composite pane 100 with respect to p-polarized radiation irradiated at an angle of incidence of 70° as a function of the wavelength in the spectral range from 380 nm to 800 nm.

[0193] Fig. 25 shows that the reflectance of a composite pane 100 with the structure shown in Table 2 with respect to s-polarized radiation is on average 0.40 and is thus approximately twice as high as the average reflectance with respect to p-polarized radiation, which is on average 0.18. If the composite pane 100 with the structure shown in Table 2 is irradiated with a mixture of s-polarized radiation and p-polarized radiation in a ratio of 1 to 1, this results in an average reflectance of 0.29 in the range from 380 nm to 800 nm.

[0194] Fig. 26 shows reflection spectra of an embodiment of a composite pane 100 according to the invention, which is constructed as indicated in Table 3. The reflection spectrum L shows the reflectance of the composite pane 100 with respect to s-polarized radiation irradiated at an angle of incidence of 60° as a function of the wavelength in the spectral range from 380 nm to 800 nm. The reflection spectrum M shows the reflectance of the composite pane 100 with respect to s-polarized radiation irradiated at an angle of incidence of 70° as a function of the wavelength in the spectral range from 380 nm to 800 nm. The reflection spectrum N shows the reflectance of the composite pane 100 with respect to p-polarized radiation irradiated at an angle of incidence of 60° as a function of the wavelength in the spectral range from 380 nm to 800 nm.The reflection spectrum Q shows the reflectance of the composite pane 100 with respect to p-polarized radiation irradiated at an angle of incidence of 70° as a function of the wavelength in the spectral range from 380 nm to 800 nm.

[0195] Fig. 26 shows that the reflectance of a composite pane 100 with the structure shown in Table 3 with respect to s-polarized radiation is on average 0.53 and is thus approximately twice as high as the average reflectance with respect to p-polarized radiation, which is on average 0.27. If the composite pane 100 with the structure shown in Table 3 is irradiated with a mixture of s-polarized radiation and p-polarized radiation in a ratio of 1 to 1, this results in an average reflectance of 0.40 in the range from 380 nm to 800 nm.

[0196] A comparison of Fig. 24 to 26 shows that a composite pane 100 with a reflective layer 7 consisting of a NiCr layer and a TiCh layer applied to the NiCr layer has a higher reflectance with respect to s-polarized radiation and with respect to p-polarized radiation than a composite pane 100 with a reflective layer 7 consisting of a NiCr layer and also has a higher reflectance with respect to s-polarized radiation and with respect to p-polarized radiation than a composite pane 100 with a reflective layer 7 consisting of a TiCh layer.

[0197] List of reference symbols:

[0198] 100 composite panes

[0199] 101 Projection arrangement

[0200] 1 outer pane

[0201] 2 inner pane

[0202] 3 thermoplastic intermediate layer

[0203] 4 Masking layer

[0204] 5 adhesive layer

[0205] 5a opaque colored adhesive layer

[0206] 5b colorless adhesive layer

[0207] 6 glass pane

[0208] 7 Reflective layer

[0209] 7a dielectric layer

[0210] 7b metallic layer

[0211] 8 opaque layer

[0212] 9 Protective layer

[0213] 10 imaging unit

[0214] O Top edge of the laminated pane 100

[0215] U Bottom edge of the laminated pane 100

[0216] S Side edge of the laminated pane 100

[0217] I outside surface of the outer pane 1

[0218] 11 Interior surface of the outer pane 1

[0219] III outer surface of the inner pane 2

[0220] IV Interior surface of the inner pane 2

[0221] V outer surface of the glass pane 6

[0222] VI Interior surface of the glass pane 6

[0223] A Area in which the masking layer 4 is arranged

[0224] B Area in which the glass pane 6 is arranged

[0225] X'-X intersection line

[0226] Y'-Y intersection line

Claims

Patent claims Composite pane (100), comprising at least - an outer pane (1) with an outside surface (I) and an inside surface (II), - a thermoplastic intermediate layer (3), - an inner pane (2) with an outside surface (III) and an inside surface (IV), - a masking layer (4), - an adhesive layer (5), - a glass pane (6) with an outside surface (V) and an inside surface (VI) and a thickness of 20 μm to 300 μm, wherein the thermoplastic intermediate layer (3) is arranged between the outside pane (1) and the inside pane (2), the masking layer (4) is arranged between the outside pane (1) and the inside pane (2) in a region of the composite pane (100), the adhesive layer (5) is arranged between the inside pane (2) and the glass pane (6), a reflective layer (7) for reflecting light is arranged on the outside surface (V) of the glass pane (6) and / or on the inside surface (VI) of the glass pane (6), 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;and wherein the adhesive layer (5) is formed as an opaque colored adhesive layer (5a) or the adhesive layer (5) is formed as an opaque colored adhesive layer (5a) or a colorless adhesive layer (5b) and an opaque layer (8) is arranged between the adhesive layer (5) and the glass pane (6) immediately adjacent to the adhesive layer (5). Composite pane (100) according to claim 1, wherein the glass pane (6) has a thickness of 50 pm to 200 pm, preferably of 50 pm to 100 pm. Composite pane (100) according to claim 1 or 2, wherein the reflective layer (7) reflects at least 10%, preferably at least 25%, of visible light.; 4. Composite pane (100) according to one of claims 1 to 3, wherein the reflection layer (7) contains or consists of a dielectric layer (7a) and / or a metallic layer (7b).

5. Composite pane (100) according to claim 4, wherein the dielectric layer (7a) is a single-layer or multi-layer layer and has or consists of at least one high-index layer with a refractive index greater than 1.

9.

6. Composite pane (100) according to claim 5, wherein the dielectric layer (7a) has a thickness of 1 nm to 120 nm, preferably of 40 nm to 80 nm, particularly preferably of 50 nm to 70 nm.

7. Composite pane (100) according to one of claims 4 to 6, wherein the metallic layer (7b) contains or consists of at least one metal selected from a group consisting of zirconium, hafnium, silver, gold, nickel, chromium, molybdenum, tungsten, copper, vanadium, niobium, tantalum, palladium, platinum, titanium, zinc, tin or aluminum or alloys thereof.

8. Composite pane (100) according to claim 7, wherein the metallic layer (7b) has a thickness of 1 nm to 100 nm, preferably of 5 nm to 50 nm, particularly preferably of 8 nm to 15 nm.

9. Composite pane (100) according to one of claims 1 to 8, wherein the reflective layer (7) is arranged on the outer surface (V) of the glass pane (6).

10. Composite pane (100) according to one of claims 1 to 9, wherein the masking layer (4) is formed as an opaque cover print arranged on the interior-side surface (II) of the outer pane (1) or the exterior-side surface (III) of the inner pane (2) or as an opaquely colored region of the thermoplastic intermediate layer (3).

11. Projection arrangement (101) comprising at least - a composite pane (100) according to one of claims 1 to 10, - an imaging unit (10) directed onto the reflection layer (7). The projection arrangement (101) according to claim 11, wherein the imaging unit (10) emits s-polarized radiation and p-polarized radiation in a ratio of between 1:10 and 10:1 to one another, or the imaging unit (10) emits circularly polarized radiation. The projection arrangement (101) according to claim 12, wherein the imaging unit (10) comprises a λ / 2 retardation plate, by means of which the ratio of the s-polarized radiation and p-polarized radiation emitted by the imaging unit (10) can be varied. Method for producing a composite pane (100) according to one of claims 1 to 10, at least comprising a) providing a composite of an outer pane (1) with an outside surface (I) and an inside surface (II), a thermoplastic intermediate layer (3) and an inner pane (2) with an outside surface (III) and an inside 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); b) providing a glass pane (6) with an outer surface (V) and an inner surface (VI) and a thickness of 20 μm to 300 μm, wherein a 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); c) bonding the glass pane (6) 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,wherein the adhesive layer (5) is formed as an opaque colored adhesive layer (5a) or the adhesive layer (5) is formed as an opaque colored adhesive layer (5a) or a colorless adhesive layer (5b) and an opaque layer (8) is arranged between the adhesive layer (5) and the glass pane (6) immediately adjacent to the adhesive layer (5). Use of a composite pane (100) according to one of claims 1 to 10 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.

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