Selectively heatable vehicle pane

Abstract

The invention relates to a vehicle pane (100) comprising - at least one pane (1) acting as an optical waveguide having an outer surface (I) and an inner surface (II), and a peripheral edge surface (S1, S2, U, O), and - at least one radiation source (2) for radiation (3) in the infrared wavelength range, the radiation source (2) emitting radiation in an infrared wavelength range of λ = 1.3 µm to 3.5 µm, and being positioned so as to be connected to the pane (1) in such a way that the infrared radiation (3) emitted by the radiation source (2) is coupled into the pane (1) in an entry region, and, at least in a passive exit section for the infrared radiation (3) of the radiation source (2), an infrared radiation-reflecting layer (4) is arranged on the peripheral edge surface (S1, S2, U, O). The invention also relates to a method for manufacturing such a vehicle pane (100), and to a vehicle component comprising a vehicle pane (100).

Description

[0001] SAI NT-GOBAI N SEKURIT FRANCE

[0002] 1

[0003] Selectively heated vehicle window

[0004] The invention relates to a selectively heatable vehicle window, a method for producing such a vehicle window, and its use.

[0005] One challenge when driving is heating vehicle windows to prevent icing or fogging, which obstructs visibility. This obstructed view also affects windows that serve as projection surfaces for displays based on HUD technology. The window is usually heated using heated air that is blown onto the window via inlets. This type of heating is summarized under the Heating, Ventilation and Air Conditioning (HVAC) method. In addition to the enormous energy consumption, the inlets through which the hot air is transported and blown onto the window require a lot of space. Furthermore, the outlet nozzles must be mounted in a specific geometric relationship to the window, which in turn significantly limits the design and construction freedom.

[0006] Heated vehicle windows are well known. They are used primarily as heated windshields in motor vehicles and offer the possibility of conveniently removing ice or condensed moisture from the windshield by heating it. They feature transparent, electrically conductive coatings, particularly silver layers. The coatings are electrically connected so that a current can be passed through them. This heats up the coating, which is responsible for the heating effect. For example, see WO2013 / 104438A1.

[0007] A common problem with electrically conductive coatings is their high sheet resistance, which, especially when the pane to be heated is large or the current paths are long, requires a high operating voltage that is certainly higher than the usual on-board voltages in vehicles. WO 2013 / 104439 A1 and EP 2803246 B1 disclose an electrically conductive coating for heating a pane, consisting of different layers that can slightly reduce the sheet resistance. Furthermore, heat and thus energy loss through convection across the usually large pane surfaces is very high. Another disadvantage of heatable coatings is that silver layers, for example, are impermeable to high-frequency radiation. This impairs, for example, the reception of mobile phone signals, communication with cloud servers (“Internet of Things”), and similar functions.This can cause problems, especially in electric vehicles. Some vehicle manufacturers, especially electric vehicle manufacturers, therefore reject the use of silver-containing coatings.

[0008] A further challenge for electrically conductive coatings, which are often multi-layered, for heating vehicle windows is the visually appealing appearance, as well as compliance with required standards, for example with regard to light transmission and color neutrality, especially for windshields, but also rear windows or side windows for vehicles.

[0009] If the vehicle window is constructed as a laminated pane, thermal radiation can also be used to prevent fogging or icing. JP2013001611A discloses a laminated pane with an IR radiation-absorbing intermediate layer. Irradiating the laminated pane with IR radiation heats the laminated pane through the absorbing intermediate layer, thereby reducing fogging or icing.

[0010] DE202022105849 U1 also follows a similar principle, proposing to provide a heatable composite pane with an outer pane and an inner pane that are connected to one another via a thermoplastic intermediate layer, wherein a coating based on a photothermal material (PTM coating) is arranged on at least one surface of the two panes and the composite pane is equipped with a radiation source in the near infrared range (N IR radiation) that is suitable for irradiating and thereby heating this coating. The PTM coating can, for example, be made of cesium tungsten oxide. The wavelength of the radiation source is selected such that the PTM coating has a particularly high absorption in this wavelength range. The coating then heats up as a result of the irradiation and thus heats the composite pane particularly efficiently.If IR radiation is coupled onto the window, it irradiates the PTM coating applied to it from the interior of the window. To ensure that the NIR radiation is coupled out via the PTM-coated surface of the window and not totally reflected, a highly optically refractive layer or a scattering structure is applied to the window surface below the PTM coating. JP 2014-104841 takes a different approach, describing a film-like de-icing device that is applied, for example, to the outer surface of a windshield. This consists of a middle layer made of a first medium that transmits IR rays from an IR radiation source and is sandwiched between two layers of a second medium that reflects IR rays.An IR radiation source is mounted in such a way that the rays enter the first medium at one side edge of the film-shaped de-icing device, are transmitted therein, and are reflected multiple times at the two interfaces to the outer layers of second medium. If the IR radiation is reflected from the surface facing the first medium, an evanescent wave of IR radiation emerges on the opposite surface of the second medium. If this is the surface facing the outside environment, aqueous deposits such as ice and moisture can be heated and thus removed by absorbing the escaping, evanescent IR radiation. The first medium preferably has a higher refractive index than the second medium.The first medium is a thin film of quartz with a refractive index of 1.45, and the second IR-reflecting medium is a fluorine- or sodium-doped quartz with a refractive index of 1.43. The second medium is used with a much thinner layer thickness of 500 nm or less than the first film medium. Furthermore, an IR-reflecting mirror layer is applied to the edge of the film-shaped de-icer opposite the radiation source, which reflects the IR radiation back into the windshield.

[0011] FR960125A and US20110067726A1 show laminated glass panels designed as windshields with IR radiation sources. If water droplets or frost are present on the windshield, the IR radiation source can irradiate the windshield, causing any watery films on the windshield to evaporate.

[0012] DE102011079191 A1 describes a heatable pane in which IR radiation emitted by an IR radiation source is coupled into the pane. The pane serves as an IR light guide, with the coupled IR light being totally reflected on its inner surface. The IR radiation source can be coupled to one narrow side of the pane. On the opposite narrow side, the pane can be provided with an infrared-reflecting coating. A maximum infrared wavelength of 950 nm is specified for the IR radiation source. This heats the pane itself, while also emitting IR radiation from disturbed areas of the surface, such as those covered with ice. This radiation then heats and melts the ice.

[0013] For rear windows, the current standard method for defrosting and removing condensed moisture is the use of printed heating wires, for example, using Joule heating, also known as ohmic heating and resistance heating. The heating wires can be applied to a tempered window using silver printing. These clearly visible, printed stripes are undesirable, primarily from an aesthetic point of view. In addition, the heating prints (printed heating wires) must be applied directly to the tempered rear window and electrically connected via cables and connectors, and functionally connected, if necessary, to a control system or the on-board electronics.This requires additional process steps such as connecting cables and terminals, such as the printing and soldering of busbars (flat and bus bars), which must now be carried out using lead-free alloys as required. This can lead to increased stresses in the glass and, as a result, glass breakage. The printed heating wires themselves, which are usually printed with silver, are also susceptible to damage. This can lead to the failure of entire heating lines and, as a result of damage, to the formation of hot spots. The necessary cables and connections, in turn, must be optically concealed, for example, with masking prints, to achieve an appealing aesthetic appearance.

[0014] Standard vehicle side windows usually do not have any window heating, apart from a limited supply of heated air from any HVAC system. These windows, especially those designed as movable, openable vehicle windows, pose particular challenges for heating.

[0015] There is therefore a general need for improved vehicle windows that can be freed from watery, obstructive deposits. Water can appear, for example, as a coating of condensed moisture, in the form of drops, or in the form of ice. In particular, there is a need for a heating system that is also suitable for single-pane vehicle glazing, such as tempered side windows, and that does not require complex modifications to the window.

[0016] The present invention is therefore based on the object of providing such an improved, particularly effective and energy-efficient heated vehicle window that has a visually appealing appearance and can also meet the required standards, such as light transmission and color neutrality. The vehicle window should be simple and cost-effective to manufacture.

[0017] These and other objects of the present invention are achieved by a vehicle window according to claim 1. Preferred embodiments are evident from the subclaims.

[0018] The selectively heatable vehicle window according to the invention comprises at least one pane with an outside surface I, an interior surface II and a circumferential edge surface for separating a vehicle interior from the external environment, which acts as an optical waveguide, and at least one radiation source for radiation in the IR wavelength range from A = 1.3 pm to 3.5 pm, wherein the radiation source is arranged so as to be connected to the pane that the IR radiation emitted by the radiation source is coupled into the pane in an entry region and an IR radiation-reflecting layer is arranged on the circumferential edge surface at least at one passive exit section for the IR radiation of the radiation source.

[0019] According to the invention, “selectively heatable” means that the vehicle window can be selectively freed, in particular from water-based deposits such as ice and / or condensed moisture, without the window itself being heated. This is achieved according to the invention by an active heating effect using IR radiation in the wavelength range from λ = 1.3 pm to 3.5 pm. The radiation source couples IR radiation in a wavelength range from λ = 1.3 pm to 3.5 pm into the window as an optical waveguide. The window, made of glass for example, is suitable as an optical waveguide for conducting the IR radiation by utilizing total internal reflection. If water is present on the window, for example as fogging or ice, the IR radiation can be selectively coupled out in these water-covered areas because water has a lower refractive index than glass, i.e. it is an optically less dense medium.The IR radiation is absorbed and the water molecules in ice crystals and water droplets are excited by the IR radiation. This causes the ice to melt and the water to evaporate. Energy loss through convection is advantageously largely eliminated.

[0020] According to the invention, a "passive exit section" is understood to be an area on the circumferential edge surface of the pane in which at least a portion of the IR radiation from the radiation source, which was guided through the pane as an optical waveguide, could exit the pane again unused (couple out), i.e. without achieving the desired active heating effect. By arranging an IR radiation-reflecting layer in at least one such passive exit section on the edge surface of the pane, the IR radiation is reflected back into the pane, transmitted therein, and can in turn be available for the coupling out and absorption of the IR radiation in surface areas of the pane covered with water. Energy loss due to unused, coupled out IR radiation can thus be reduced or even prevented.The selective heating effect can thus be advantageously intensified and accelerated without additional energy input.

[0021] The pane has an outside surface I (side I) and an inside surface II (side II). The outside surface I is intended to face the outside environment when the vehicle window is installed in a vehicle and is also called the outside. The inside surface II is intended to face the vehicle interior when the vehicle window is installed in a vehicle and is also called the inside. The optical fiber, i.e. the pane, has a circumferential edge surface. The circumferential edge surface comprises an upper edge and a lower edge as well as two side edges connecting the upper and lower edges. In the installed position, the upward-facing edge is referred to as the upper edge (for example the roof edge in a motor vehicle), and the downward-facing edge of the optical fiber (for example the engine edge in a motor vehicle) is referred to as the lower edge.The edges in between are called side edges.

[0022] The vehicle window is intended to separate the interior from the exterior environment in a window opening of a vehicle. It is particularly preferably the side window or the rear window of a passenger car or truck. In a particularly advantageous embodiment, the vehicle is an electric vehicle.

[0023] The vehicle window is preferably a single-glazed vehicle window, i.e., a vehicle window with only one pane, which is preferably formed as a single glass pane. The vehicle window can comprise conventional coatings, prints, for example, conventional enamel cover prints, and other elements. A major advantage of the invention is that large-area, electrically heatable layers, such as silver layers, or a de-icing layer structure as described in JP 2014-104841, or heating layers made of photothermal material (PTM), as disclosed, for example, in DE202022105849 U1, can be dispensed with. This leads to simplified, more cost-effective production of the vehicle window.Furthermore, the permeability of high-frequency radiation, for example, for receiving mobile phone signals, communicating with cloud servers (“Internet of Things”), and the like, is not impaired by the IR radiation heating system according to the invention, thus providing further advantages. The selective heating effect is also supported by the fact that in the selected range of the IR radiation, its absorption within the pane is particularly low, thus preventing the pane itself from being heated. Heat loss across the entire surface of the pane can thus be minimized, and the energy can be selectively channeled into the evaporation of aqueous deposits on the pane. Heat loss, and thus energy loss, across the pane surface does not occur, making the invention particularly energy-efficient.A particularly great advantage of the invention is that the described heating effect is particularly applicable to vehicle windows, which, for example, due to their significantly lower thickness, stability properties and / or a movable design, place completely different requirements on the structure with a radiation source than, for example, fixed and immovably installed windows.

[0024] The fact that the radiation source is arranged so as to be firmly connected to the window also means, within the meaning of the invention, that the radiation source is arranged such that its position relative to the optical fiber (window) does not change even when the vehicle window moves. This means that if, for example, the vehicle window is a vehicle side window that can be opened and closed, the radiation source is arranged in the same way relative to the window, even during opening and closing, as well as at the respective start and end points of the vehicle side window. This also means that the relative position of the optical fiber to the radiation source is the same everywhere, regardless of location. This advantageously ensures an efficient heating effect in any position of the vehicle window in a vehicle (in a window that is only half-open, for example).

[0025] In a preferred embodiment, the IR-reflecting layer is formed as a coating or an IR-reflecting film. In a further configuration, the IR-reflecting layer is simultaneously opaque or transparent to radiation in the visible wavelength range (visible light spectrum means light with a wavelength of 380 nm to 780 nm). In other words, the IR-reflecting layer can appear to an observer as an opaque mirror layer or be invisible or barely visible to an observer (transparent). Preferably, the IR-reflecting layer is transparent, which is usually advantageous for a visually appealing appearance of the vehicle window.

[0026] "Transparent" in the sense of the invention means a light transmission (according to ISO 9050:2003) of at least 70%, preferably at least 80%, and particularly preferably at least 85%. "Semi-transparent" (according to ISO 9050:2003) in the sense of the invention means a light transmission of at most 70%, preferably at most 50%, and particularly preferably at most 30%. "Opaque" in the sense of the invention means a light transmission (according to ISO 9050:2003) of less than 30%, preferably less than 20%, particularly preferably less than 5%, and especially less than 0.1%. With regard to the determination of the luminous transmittance according to ISO 9050:2003 (see point 3.3 in the standard), the relative spectral distribution of illuminant D65 (see, for example, ISO 11664-2:2007) and / or the relative spectral distribution of illuminant A (see, for example, ISO 11664-2:2007) can be used for the determination.In other words: the described light transmittance ranges apply to the determination using illuminant A and / or illuminant D65.

[0027] In a preferred embodiment, the IR-reflecting layer is formed as a coating based on a metal or a metal alloy, preferably based on silver, chromium, aluminum, nickel, or tungsten. In an alternative preferred embodiment, the IR-reflecting layer can be a transparent coating based on an electrically conductive oxide, preferably indium tin oxide (ITO). Such coatings and their production are known. Silver-containing, transparent coatings are known, for example, from WO003 / 024155, US2007 / 0082219A1, US2007 / 0020465A1, WO2013 / 104438, or WO2013 / 104439.

[0028] If a coating is based on a material, it consists predominantly of this material, in particular essentially of this material, along with any impurities or dopants.

[0029] The IR-reflecting coating can be applied to the edge surfaces, for example, as a varnish or as a paste containing reflective pigments. Alternatively, the IR-reflecting coating can be applied using conventional wet coating processes, such as spray or dip coating, application by roller or brush, or by printing processes, such as pad printing or screen printing. Drying can then take place, during which any solvent is evaporated. This drying can take place at ambient temperature or by separate heating. The edge surface can be sanded and cleaned in a conventional manner before applying the coating.

[0030] Alternatively, the IR-reflecting layer can be applied to the edge surface as a reflective film, for example, made of coated PET (polyethylene terephthalate) with a suitable adhesive. Thus, an IR-reflective coating can be applied to a carrier film, or a coating-free IR-reflecting polymer film can be bonded to the edge surface, for example, by adhesive bonding. Typical carrier films are made of PET and have a thickness of, for example, 50 μm. Such films are commercially available.

[0031] In a further embodiment of the invention, the IR-reflecting layer can additionally extend to an edge region, starting from the peripheral edge area of ​​less than 10 mm, on the outside surface I and / or the inside surface II of the pane. Such a "wider" IR-reflecting layer can better prevent the unused coupling of IR radiation through the edges of the pane and may also be easier to produce with some coating processes. To ensure that the IR-reflecting coating is applied only in the desired areas, conventional masking techniques or covering with tape or film can be used.In addition to or independently of whether the IR-ray reflecting layer extends over an edge region of the interior and / or exterior surface of the pane, the IR-ray reflecting layer preferably covers the peripheral edge surface of the pane to at least 30%, particularly preferably to at least 50%, very particularly preferably to at least 80% and in particular completely.

[0032] In a preferred embodiment, the IR-reflecting layer has a thickness of 5 nm to 50 nm.

[0033] In a further preferred embodiment, a protective layer is arranged on the side of the IR-reflecting layer facing away from the pane. This protective layer arranged on the IR-reflecting layer is then the layer exposed to the environment and protects the IR-reflecting layer, for example, from corrosion and mechanical damage, such as scratches. The protective layer is preferably made of a polymeric material based on polyacrylates, polyoximes, alkyd resins, polyurethanes, or mixtures thereof. In another preferred embodiment, the protective layer contains or consists of diamond-like amorphous carbon (DLC). The protective layer preferably has a thickness of 50 nm to 10 pm, and particularly preferably of 100 nm to 5 pm. The protective layer is preferably applied to the IR-reflecting layer by spraying or atomizing, for example using a pressure atomizer.The protective layer can advantageously increase the durability of the IR-ray reflecting layer.

[0034] In a preferred embodiment, the radiation source is suitable for emitting IR radiation in an IR wavelength range from A = 1.4 pm to A = 3.3 pm, particularly preferably in a range from A = 1.4 pm to A = 3.1 pm.

[0035] In a particularly preferred embodiment, it is provided that the radiation source emits IR radiation (3) in an IR wavelength range from A = 1.4 pm to A = 1.6 pm, preferably 1.45 pm to 1.55 pm or in an IR wavelength range from 1.9 pm to 2.1 pm, preferably 1.95 pm to 2.05 pm, or from A = 2.9 to A = 3.1 pm, for example from A = 3.0 pm.

[0036] It is not necessary for the emission band of the radiation source to completely cover the specified ranges. However, the emission band should lie (at least partially) within these ranges. The radiation source is preferably connected to a power supply.

[0037] In the wavelength range from A = 2.6 pm to A = 3.1 pm, the absorption and excitation of water molecules, and thus the resulting heating and evaporation, is particularly high. Advantageously, it has been shown that in glass, the transmission in the wavelength range from A = 2.9 pm to A = 3.1 pm is particularly high at over 70%, especially at approximately A = 3.0 pm at approximately 85%, so that the energy can be used efficiently for defrosting and evaporating water.

[0038] In the alternatively mentioned preferred range, the radiation source is suitable for IR radiation in

[0039] IR wavelength range from A = 1.4 pm to A = 1.6 pm or from A = 1.9 pm to A = 2.1 pm. In this range, the radiation is particularly energy-intensive and therefore very suitable for evaporating water.

[0040] The radiation source preferably comprises an LED, OLED, and / or a laser diode, preferably an LED. In particular, the radiation source comprises an LED, which can also be referred to as an "IR-emitting diode." Alternatively, the radiation source can comprise laser diodes or lasers, which have the advantage of being particularly powerful and efficient. In addition to the aforementioned elements for generating IR radiation, the radiation source can also comprise further elements, for example, a housing in which the elements for generating IR radiation are mounted. Alternatively, the radiation source can be an LED, OLED, and / or a laser diode.

[0041] In an exemplary embodiment of the invention, the radiation source comprises or consists of an Er:YAG diode. The Er:YAG diode has a wavelength of approximately 2960 nm. Other examples are InAs / GaSb, Er 3+ -doped sesquioxide diodes. For example, an InGaAsP diode with a wavelength of 1900 nm can also be used. These wavelength ranges correspond to the frequency and wavelength ranges in which water molecules exhibit the highest absorption coefficients for IR radiation. At the same time, the transmission of glass in this IR radiation range is particularly high, with TL > 80%, and only a small portion of the IR radiation is absorbed.

[0042] The radiation sources can be strip-shaped or spot-shaped, for example. Other geometric shapes are also possible. Several individual radiation sources can also be arranged next to each other, spaced apart, or in a strip-shaped configuration (close to one another). In other words, if several spot-shaped LEDs are arranged next to each other, a multi-part, strip-shaped radiation source can be formed. This allows the number and intensity of the radiation sources to be flexibly adapted to the requirements for selective heating of the respective vehicle window, for example, with regard to the spatial and geometric conditions and the energy required for efficient heating.

[0043] In a preferred embodiment, the pane is preferably a glass pane, particularly preferably made of soda-lime glass, which is common for vehicle windows, for example in the form of toughened safety glass (ESG). In principle, however, the pane can also be made of other types of glass (e.g. borosilicate glass, quartz glass, aluminosilicate glass). Alternatively, the pane can also be made of plastic, i.e., transparent polymers, for example, polycarbonate. The thickness of the pane can vary widely. Preference is given to panes with a thickness in the range of 0.5 mm to 10 mm, preferably 1 mm to 5 mm, particularly preferably 3.15 mm to 4.85 mm. The optical fiber is preferably a glass pane and particularly preferably has an iron oxide content of a maximum of 1 wt.%. This low iron oxide content of the glass pane makes the glass pane particularly suitable as an optical fiber for IR radiation.

[0044] In a preferred embodiment, the radiation source can be functionally connected to at least one sensor, in particular a temperature and / or humidity sensor. This can advantageously be used for automated defrosting or the removal of condensed moisture. In addition, icing of the vehicle window or the formation of condensate and the associated obstruction of visibility can be prevented. Such a sensor is preferably attached to the window. The heating device can be functionally connected to a controller, in particular to on-board electronics, and / or to one or more environmental sensors, and these can communicate with each other.The environmental sensor(s) may in particular comprise one or more temperature sensors, humidity sensors, conductivity sensors, and / or a variety of other sensors that may be configured to detect environmental conditions and vehicle window states related to demisting and / or frost on the windows of a vehicle. During operation, the controller may monitor the status of the environmental sensors and, for example, automatically activate the heating system to remove ice or condensation from the vehicle windows and / or prevent frost and / or moisture from accumulating on the vehicle windows. During operation or starting of the vehicle, a controller in operative connection with the sensors may identify whether moisture is detected by the humidity sensor and / or whether the temperature sensor registers a temperature below a freezing threshold.Accordingly, based on the detected humidity level and / or the specified temperature, the controller can determine whether a condition exists to automatically switch on the heating system to heat one or more of the vehicle windows and demist. Manual switching on of the heating system can also be provided alternatively or additionally. In a further preferred embodiment of the invention, at least one radiation source is arranged on at least one edge surface of the window, which accordingly comprises the entry region for the IR radiation, wherein the IR radiation-reflecting layer is arranged at least partially, in a passive exit section, on at least one edge surface opposite this edge surface and the entry region.

[0045] The radiation source can, for example, be assigned in sections to at least one side edge surface and / or attached to the upper edge and / or the lower edge, for example glued or arranged in a holder fastened to the pane, or it can completely occupy an edge surface. The IR radiation can then, for example, be coupled into the pane via one, two, three or three edge surface sections. It can be advantageous to irradiate the pane from one or more sides with several radiation sources in order to increase the heating effect accordingly. A particular advantage of the present invention is that the heating effect is additionally increased by the provided IR-reflecting layer and, compared to a design without this measure, fewer radiation sources and less energy is required for the same heating effect.

[0046] In one embodiment of the vehicle window according to the invention, the radiation source(s) are located at the lower edge, for example, distributed substantially across the entire lower edge or arranged directly adjacent to one another. This is particularly suitable for vehicle side windows that can be opened and closed. Typically, the lower edge of the vehicle window is concealed by vehicle components in all positions of the window (open, half-open, closed).

[0047] In a further embodiment of the invention, the at least one radiation source is arranged in a recess in the pane. The radiation source is arranged in the recess in such a way that the radiation source can couple IR radiation into the optical fiber, which can then be used either to remove condensed moisture or for de-icing. The recess in the pane is, for example, a hole, i.e. a feedthrough, which extends continuously between the first and the second surface of the pane. Alternatively, the recess can also be a depression in the manner of a blind bore (bag-like depression), which extends from the second surface or the first surface into the pane, but without reaching the opposite main surface, which would result in a feedthrough. The recess can be created, for example, by mechanical drilling or by laser processing.The recess is preferably round, but can in principle have any desired shape, for example, even a polygonal shape. This refers to the base area of ​​the recess in the plane of the at least one surface of the optical waveguide, via which the recess is introduced into the optical waveguide. The recess has the overall shape of a cylinder, preferably a vertical cylinder. The cylinder is preferably a circular cylinder (circular base area), but can also have any other base area, for example, an elliptical base area (elliptical cylinder) or a polygonal base area (prism).

[0048] The recess, whether a through-hole or a depression, is defined by a circumferential edge surface extending between the main surfaces of the disc. In the case of a through-hole, this is the only boundary surface of the recess. In the case of a pocket-like depression, there is a further boundary surface facing the main surface of the disc to which the depression does not extend, and which, as it were, forms the bottom of the pocket hole.

[0049] The radiation source is arranged on the edge surface of the recess in the pane, preferably attached, in particular glued, or arranged in a mount attached to / in the recess. The IR radiation is then coupled into the optical fiber via the inner edge surface and, due to the lower refractive index of water, selectively coupled out of the interior of the optical fiber in areas covered with water, for example, in areas of existing ice or in areas with condensed moisture.

[0050] Mixtures and combinations of the above-described embodiments are also possible. For example, the optical waveguide can be irradiated and heated with a radiation source at the lower edge and additionally with another radiation source on the second surface of the optical waveguide. Likewise, a radiation source can be arranged in a recess in the pane and an additional radiation source can be attached to an edge of the pane. These are merely exemplary embodiments and are not intended to be exhaustive.

[0051] A preferred embodiment provides that the radiation source is functionally connected to at least one control unit and / or on-board electronics. The radiation source can be controlled, in particular, by means of the control unit and / or the on-board electronics. Preferably, the control unit or the on-board electronics also serve as a voltage source for the radiation source.

[0052] In one embodiment, the radiation source is applied to one surface, for example the second surface of the window, and a second IR mirror layer, i.e. a second reflective coating for the infrared range, is applied to the first surface of the window, which is arranged so as to cover the at least one radiation source when viewed through the vehicle window. The optical fiber is thus irradiated with IR radiation via the second surface. The at least one radiation source is attached to the second surface of the optical fiber, for example, adhered with an optically clear adhesive (OCA). As a result, the IR radiation is coupled into the optical fiber via reflection from the IR mirror layer. This reduces the complexity of the vehicle window, since the radiation source does not have to be arranged on the edge surfaces of the optical fiber.Alternatively, the IR reflective layer can also be applied to the first surface of the optical fiber. In this case, the radiation source is applied to the second surface. When viewed through the vehicle window, the IR reflective layer and the radiation source overlap, essentially overlapping each other.

[0053] An optically clear adhesive (OCA) is preferably a material that contains or is made from polyacrylate compounds (e.g., polyacrylate or polymethylacrylate) or silicone. "Clear" in the context of the invention means that the adhesive is transparent.

[0054] When using a (second) IR mirror layer for coupling, the IR radiation from the radiation source is (at least partially) reflected back toward the window by the IR mirror layer, where the IR radiation is coupled into the optical fiber using the principle of total internal reflection. This helps distribute the IR radiation within the window and direct it to the areas that need to be heated, i.e., icy or moist areas of the vehicle window.

[0055] IR mirror layers are known per se and can, for example, like the IR-reflecting layer in the passive exit section, also be designed as a silver-containing coating or as a layer of an electrically conductive oxide (transparent conductive oxide, TCO), such as indium tin oxide (ITO). Alternatively, the IR mirror layer for coupling the IR radiation, also referred to herein as the coupling mirror layer, can be arranged on the pane in the form of a coated thermoplastic film, for example made of polyethylene terephthalate (PET). In this embodiment, the radiation source(s) is / are preferably arranged in an area of ​​the pane that, in the installed position, cannot be seen from the vehicle interior or the external environment (for example, concealed by seals or other vehicle components).The second IR-coupling mirror layer is preferably a prism film, which can be additionally coated with an IR-reflecting coating based on an electrically conductive oxide. In particular, the IR-coupling mirror layer is a microprism film, which can be additionally coated with an IR-reflecting coating based on an electrically conductive oxide or metal. The inclined surfaces of the prism film result in the IR rays being reflected at a particularly advantageous angle by the IR mirror layer, so that they strike the optical waveguide at an angle of incidence at which a particularly high proportion of the IR radiation can be coupled in.

[0056] In a further embodiment of the invention, the radiation source is applied to the first surface or the second surface of the optical waveguide by means of an optically clear adhesive which is in the shape of an inclined wedge. The radiation source is preferably applied in the edge region of the disc. In the context of the invention, “inclined wedge” means a wedge shape which has two triangular side surfaces, two rectangular base surfaces and a base surface. The triangular side surfaces are not formed at right angles, so that the two base surfaces are different sizes. The base surface is the smallest of the surfaces of the inclined wedge and is arranged at an angle greater than 90° to one of the base surfaces and at an angle less than 90° to the other base surface.In this embodiment, the optically clear adhesive is applied to the pane such that the base surface is at an angle of less than 90° to the base surface of the wedge, which is in contact with the surface of the optical waveguide. The radiation source is arranged such that the IR radiation is first transmitted through the optically clear adhesive before subsequently penetrating the pane, with the IR radiation being at least partially coupled into the optical waveguide by utilizing the effect of total internal reflection. The radiation source is arranged such that, during operation, it irradiates the base surface of the optically clear adhesive, with the emitted IR radiation preferably impinging on the optically clear adhesive perpendicular to the base surface. The base surface of the optically clear adhesive is preferably at an angle to the surface of the optical waveguide that is suitable for coupling IR radiation into the pane as an optical waveguide.The optically clear adhesive preferably has a refractive index that differs by less than 0.1, preferably less than 0.05, from the refractive index of the pane. As a result, the IR radiation is hardly refracted at the interface between the optically clear adhesive and the optical fiber, or at least significantly less refracted. Nevertheless, any existing radiation refraction between the optically clear adhesive and the optical fiber can be taken into account when selecting the angle of the base surface to the surface of the optical fiber.

[0057] In a further embodiment of the invention, the vehicle window comprises at least one additional radiation source, preferably at least two additional radiation sources, which are suitably arranged to couple IR radiation into the window. The radiation sources can preferably be switched and operated independently of one another. Thus, the associated radiation sources can be controlled independently of one another, allowing the heating strength or intensity to be selectively adjusted.

[0058] In a preferred embodiment, the at least one radiation source is arranged in an opaque area, preferably an edge area, for example, an area coated with a conventional masking print, of the vehicle window, which completely covers the radiation source in the viewing direction through the vehicle window. The radiation sources can thus be optically concealed from the outside.

[0059] In a further preferred embodiment of the invention, the vehicle window comprises at least one second pane having an exterior surface III (side III) and an interior surface IV (side IV), which is congruently connected to the first pane via a thermoplastic intermediate layer and has a circumferential edge surface. In other words, the vehicle window according to the invention can also be a composite pane. In this case, the first pane, but also the second pane, can additionally be formed with an IR radiation source and / or an IR radiation-reflecting layer according to the invention in accordance with the described embodiments.

[0060] The invention also extends to a vehicle or vehicle component comprising at least one selectively heatable vehicle window, as described above in various embodiments. The invention also extends to a vehicle comprising at least one heatable vehicle window, as described above in various embodiments, and at least one window seal arranged in some regions in the peripheral edge region of the vehicle side window. According to the invention, the radiation source adjoins at least a section of the window seal, at least when the vehicle window is closed, so that the waste heat from the radiation source can be used to heat the window seal. The radiation source is preferably arranged at least at the lower edge of the optical fiber, alternatively at the upper edge of the optical fiber.In particular, the radiation source is arranged along the entire peripheral edge area of ​​the optical fiber. When closed, the radiation source thus borders the window seal at least in sections. Preferably, the radiation source is in direct spatial contact with the window seal, i.e., touches it, along at least one section of the window seal.

[0061] The efficiency with which radiation sources are electrically operated is not 100% in reality, and a significant portion of the electrical energy is usually lost as heat. Due to a lack of other solutions, this heat energy is released from the radiation source into the environment as waste heat. The vehicle according to the invention can use this waste heat to heat the window seal and thus free it of ice or moisture. This can not only extend the service life of the window seal, as it is exposed to less moisture over its lifetime, but it is also advantageous if the vehicle window is prevented from opening due to ice on the window seal. This is particularly relevant for vehicle side windows.

[0062] For the purposes of the invention, “closed state” means that the vehicle window essentially completely separates the vehicle interior from the outside environment. In the case of a vehicle side window in a car, this would mean the case in which the window opening is completely closed by the vehicle side window. For the purposes of the invention, “open state” means that the vehicle side window does not completely close the window opening, i.e. the vehicle interior is not completely separated from the outside environment. It goes without saying that in the “open” state, the vehicle side window can also only be “partially open,” i.e. the window is neither fully open nor fully closed, for example when a side window of a vehicle has been wound down halfway.

[0063] The window seal preferably contains a rubber material, preferably the rubber material contains ethylene propylene diene rubber (EPDM) or consists thereof. Preferably, in addition to the rubber material, it contains a metal or a metal alloy, which is enclosed by the rubber material and thereby gives the seal stability and shape or a profile. In a preferred embodiment of the vehicle according to the invention, at least one first heat-conducting layer is arranged between the at least one section of the window seal and the radiation source, at least when the vehicle window is closed. This first heat-conducting layer is preferably applied to the radiation source and contacts the window seal, at least when the vehicle window is closed. The radiation source comprises, for example, a housing or a mount, to which the first heat-conducting layer is applied.The first heat-conducting layer is preferably applied in such a way that it does not block or partially blocks the beam path of the IR radiation.

[0064] Thermally conductive layers preferably contain or consist of copper, aluminum, and / or brass. These materials exhibit high thermal conductivity and thus efficiently heat the window seal using the waste heat from the radiation source. Thermally conductive layers are preferably uneven, particularly preferably roughened, to increase the surface area.

[0065] In a particularly preferred embodiment of the invention, a first heat-conducting layer is applied to the radiation source, and a second heat-conducting layer is applied to at least one section of the window seal. At least when the vehicle window is closed, the first heat-conducting layer and the second heat-conducting layer are in direct spatial contact with one another. Preferably, the surface of the first heat-conducting layer facing the second heat-conducting layer has an uneven surface, for example, a stepped surface. The surface of the second heat-conducting layer facing the first heat-conducting layer is also uneven, for example, stepped.When the vehicle window is closed, the mutually facing uneven surfaces of the first heat-conducting layer and the second heat-conducting layer are in direct spatial contact with one another, wherein the contact area is increased by the unevenness of the surfaces (compared to the case where the surfaces were flat, i.e., for example, substantially smooth). Particularly preferably, the radiation source also has at least one further heat-conducting layer which, at least when the vehicle window is closed, adjoins a further section of the window seal. In particular, a further heat-conducting layer is also applied to the further section of the window seal, so that the further heat-conducting layers of the radiation source and the window seal are in direct spatial contact with one another, at least when the vehicle window is closed.The invention further extends to a method for producing a vehicle window as described above in various embodiments, at least comprising the steps:.

[0066] (A) the radiation source (2) is arranged connected to the pane (1) in such a way that the IR radiation (3) is coupled into the pane, and

[0067] (B) an IR radiation-reflecting layer is formed in at least one passive exit section on the circumferential edge surface (S1, S2, U, O).

[0068] Furthermore, the invention extends to the use of the vehicle window in vehicles for traffic on land, in the air or on water, in particular as a selectively heated side window, rear window, roof window or windshield in motor vehicles, in particular in electric vehicles.

[0069] The various embodiments of the invention can be implemented individually or in any combination. In particular, the features mentioned above and those to be explained below can be used not only in the specified combinations, but also in other combinations or on their own, unless they are explicitly described and described as alternatives to one another, without departing from the scope of the present invention.

[0070] 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:

[0071] Fig. 1 shows a vehicle window according to the invention in plan view,

[0072] Fig. 1a the vehicle window according to the invention from Fig. 1 in a cross-sectional view,

[0073] Fig. 2 a vehicle window not according to the invention analogous to Fig. 1a without IR-reflecting layer,

[0074] Fig. 3 shows a further embodiment of the vehicle window according to the invention in plan view,

[0075] Fig. 3a shows the vehicle window according to the invention from Fig. 3 in a cross-sectional view,

[0076] Fig. 4 shows another embodiment of the vehicle window according to the invention in a cross-sectional view;

[0077] Fig. 5 is a plan view of a vehicle door of a vehicle according to the invention, Fig. 5a is a cross-sectional view of a vehicle window area of ​​the vehicle door from Fig. 5,

[0078] Fig. 5b an enlarged section Z from Fig. 5a and

[0079] Fig. 5c an enlarged section Z' from Fig. 5a and

[0080] Fig. 6 shows a further embodiment of a vehicle window according to the invention in cross-sectional view, and

[0081] Fig. 7 an absorption spectrum of water (liquid state).

[0082] Figure 1 shows a first embodiment of a single-glazed vehicle window 100 according to the invention as a vehicle side window of a passenger car in a plan view. Fig. 1a shows this embodiment in cross-section, wherein in Fig. 1 the cross-section is indicated by a dashed line XX'. For the sake of simplicity, the vehicle window 100 is shown flat, although in reality vehicle side windows are typically curved. The vehicle window 100 comprises an optical fiber, preferably embodied as a pane 1 (glass pane), and a radiation source 2. The pane 1 is made, for example, of soda-lime glass. The pane 1 has a thickness of 3.5 mm, for example. In the installed position, the upward-facing edge is referred to as the upper edge O (roof edge). The downward-facing edge of the pane 1 in the installed position (engine edge) is referred to as the lower edge U. The edges running between them are referred to as side edges S1, S2.The pane 1 also has an outer surface I, which faces the external environment 8, and an interior surface II, which faces the vehicle interior 9. A water coating 10 adhering to the outer surface I is shown.

[0083] An IR radiation source 2, for example an LED with a wavelength in a wavelength range of A = 1.3 pm to 3.5 pm, is arranged on the lower edge U of the pane 1. The lower edge U thus forms an entry area for the IR radiation 3. The radiation source 2 can, for example, be one or more Er:YAG diodes that have or can emit a wavelength of approximately 2960 nm. This wavelength corresponds to the frequency and wavelength range in which water molecules have the highest absorption coefficient for the IR radiation 3. At the same time, the transmission of glass in this IR radiation range <3.5 pm with TL of approximately 85% is particularly high and only a small part is absorbed. The slight absorption of the IR radiation, which could possibly lead to a slight heating of the pane 1, then also contributes to freeing it from the coating 10 via the heating.The LEDs can, for example, be glued on or arranged in a holder fastened to the pane 1. In this embodiment, the radiation source 2 is designed and / or arranged in a strip-shaped manner. Furthermore, the radiation source 2 can be functionally connected to a control and / or regulating unit, for example to the on-board electronics of a vehicle. The arrows indicate, by way of example and schematically, the radiation direction of the IR radiation 3. The IR radiation 3 is coupled into the optical fiber 1 via the lower edge U. In this exemplary embodiment shown, the IR radiation-reflecting layer 4 is arranged on the upper edge O of the pane 1, i.e., in a passive exit section substantially opposite the radiation source 2. As a result, a portion of the IR radiation 3a that would otherwise be unused for the heating effect and would be coupled out via the edge (see Fig.2) is reflected back into the pane 1 as IR radiation 3b and directed toward the water surface 10 by total internal reflection, where it is decoupled. The heating effect can thus be intensified and accelerated by the IR-reflecting layer 4. The effectiveness and energy efficiency can advantageously be further increased by the IR-reflecting layer 4.

[0084] Glass can conduct IR radiation 3 if it is coupled into the pane 1. In areas where an aqueous coating (moisture) 10 has formed and developed on the optical waveguide 1, i.e. where the pane 1 is covered, for example, with water droplets 10 or ice crystals, the IR radiation 3 is selectively coupled out because water has a lower refractive index, i.e. is an optically less dense medium than the glass of the pane 1. The IR radiation 3 is absorbed by the water molecules, which are heated by the excitation from the radiation 3 and thereby evaporated. A particular advantage of the invention is that IR radiation 3 in particular can be used with as precise a wavelength and in the frequency range as possible in which water molecules have the highest absorption coefficients, and in this way a very selective heating effect can be achieved. This contributes to achieving the heating effect in a particularly energy-saving manner.The IR-ray reflecting layer 4 used can make a further significant contribution to this.

[0085] Energy efficiency is an extremely important criterion for future product developments. Advantageously, the heating effect according to the invention does not depend on the heating of the vehicle window 100 itself, but is achieved selectively by the excitation of the water molecules by the IR radiation 3. Therefore, the heating effect occurs much more quickly than with previously used heating devices, and additionally, there is no heat loss due to convection and the large surface area of ​​the vehicle window 100. Thus, the dependence of the effect on the outside temperature is significantly lower than with previously known heating devices, which must first heat the vehicle window 100 to ultimately remove condensate and ice.By firmly attaching the radiation source 2 to the lower edge U of the optical waveguide 1, preferably by means of adhesive bonding, the vehicle window 100 can also be movable, for example, it can be opened and closed in a passenger vehicle, without the IR radiation 3 being able to be effectively coupled into the optical waveguide 1.

[0086] In Figure 1a, the vehicle window 100 according to the invention from Figure 1 is shown in a cross-sectional view.

[0087] Figure 2 shows a vehicle window not according to the invention with a structure analogous to the embodiment shown in Figure 1a, but without the IR radiation-reflecting layer 4. A small portion of the IR radiation 3 coupled in via the radiation source 2 is not used for the heating effect by the coupling out of the IR radiation 3 in the area of ​​the water 10 and absorption and excitation of the water molecules for evaporation, but is guided to the edge O and coupled out there unused. This can be reduced or avoided according to the invention by the IR radiation-reflecting layer 4, and the previously unused radiation portion 3a can be made available again by reflection to achieve the selective heating effect.

[0088] Figure 3 shows a further embodiment of a single-glazed vehicle window 100 according to the invention as a vehicle side window of a passenger car in a plan view. Figure 3a shows this embodiment in cross-section, wherein in Figure 3 the cross-section is indicated by a dashed line XX'. In contrast to the embodiment shown in Figures 1 and 1a, the radiation source 2 is arranged in a recess in the window 1. The window 1 has a recess in the form of a hole for this purpose. The hole is designed as an opening (through hole), for example cylindrical. It can be created, for example, by drilling a glass bore. The radiation source 2 is arranged within the opening. The radiation source 2 is arranged such that it can couple the IR radiation 3 directly into the window 1 via the edge region of the recess.The recess is arranged in an edge region of the pane 1 adjacent to the lower edge U. The IR-reflecting layer 4 is arranged on the entire circumferential edge surface S1, S2, U, O of the vehicle pane 100. This allows the coupled IR radiation 3 to be optimally utilized for the desired heating effect and the removal of any deposits that may obstruct visibility. Unused coupling via the edges S1, S2, U, O is thus effectively prevented.

[0089] Figure 4 shows a cross-sectional view of a further embodiment of the vehicle window 100 according to the invention, in which the radiation source 2 is arranged in an edge region of the glass pane 1 adjacent to the lower edge U of the pane 1. An IR mirror layer 5 is applied to the first surface I of the pane. This IR mirror layer 5 is, for example, a microprismatic film that is bonded to the pane 1 by means of an optically clear adhesive. During operation, the radiation source 2 emits IR radiation 3 perpendicular to the pane 1. The IR radiation 3 enters the pane 1 via the second surface II and is transmitted through it until it exits again via the first surface I of the pane 1. The IR radiation 3 then strikes the IR mirror layer 5 and is reflected back into the pane 1.The IR radiation 3 strikes the pane 1 at such an angle of incidence that the IR radiation 3 can be at least partially coupled into the optical waveguide 1. Due to the inclined surfaces of the microprismatic film, the IR radiation 3 is reflected onto the optical waveguide 1 at a suitable angle.

[0090] In the embodiment shown, a protective layer 7 is arranged on the side of the IR-reflecting layer 4 facing away from the pane 1, forming the layer ? exposed to the environment. The protective layer can protect the IR-reflecting layer 4, for example, from corrosion and mechanical damage, such as scratches, and advantageously increase its durability. The protective layer 7 is preferably made of a polymeric material, for example based on polyacrylates, polyoximes, alkyd resins, polyurethanes, or mixtures thereof. Alternatively, the protective layer 7 contains or consists of diamond-like amorphous carbon (DLC). The protective layer 7 preferably has a thickness of 50 nm to 10 pm, and particularly preferably of 100 nm to 5 pm.The protective layer 7 is preferably applied to the IR-reflecting layer 4 by spraying or squirting, for example, using a pressure atomizer. Such a protective layer 7 can also advantageously be implemented in combination with all other embodiments described herein with the IR-reflecting layer 4.

[0091] Fig. 5 shows an embodiment of a vehicle door 101 of a vehicle, which in this embodiment is a passenger car. For example, a vehicle window 100 according to the invention, as described for Fig. 1 and Fig. 1a, is installed in the vehicle door 101. However, any other embodiment of the vehicle window 100 according to the invention can optionally also be installed in the vehicle door 101. Fig. 5a shows a cross-section of the vehicle door 101 in a specific area. The section line XX' for the cross-sectional view in Fig. 5a is indicated in Fig. 5 by a dashed line. Fig. 5b shows an enlarged section Z of the edge area of ​​the vehicle window 100 adjacent to the lower edge U.

[0092] The vehicle window 100 is inserted into a window opening of the vehicle door 101. The vehicle window 100 is, for example, a vehicle side window, which can be moved electronically or manually by means of a crank from an open state to a closed state and vice versa. Fig. 5a shows a cross-section showing how the vehicle window 100 is closed, thus completely separating the vehicle interior 9 from the external environment 8. When the vehicle window 100 is closed, it is completely surrounded by an inside window seal 6 and an outside window seal 6'. The inside and outside window seals 6, 6' are thus arranged in a frame-like manner around the vehicle window 100, overlapping with the circumferential edge region of the vehicle window 100 when the window 100 is closed. The inside window seal 6 is arranged between the vehicle window 100 and the vehicle interior 9.The exterior window seal 6' is arranged between the vehicle window 100 and the external environment 8. The radiation source 2 is firmly connected to the window 1 in the area of ​​the lower edge U.

[0093] The inside window seal 6 has an inner surface A1, which faces the vehicle interior 9 and simultaneously faces away from the vehicle window 100. The inside window seal 6 also has an outer surface A2, which faces the external environment 8 and faces the vehicle window 100. The outside window seal 6' has an inner surface B1 facing the vehicle window 100 and an outer surface B2 facing away from the vehicle window 100. The outer surface B2 of the outside window seal 6' directly borders the external environment 8 and faces it. The inner surface B1 of the outside window seal 6' faces the vehicle interior 9.

[0094] The radiation source 2 has two heat-conducting layers W1, for example made of copper. One of the heat-conducting layers W1 is applied to a surface of the radiation source 2 that faces the outer surface A2 of the inside window seal 6. The other heat-conducting layer W1 of the radiation source 2 is applied to a surface of the radiation source 2 that faces the inner surface B1 of the outside window seal 6'. The inside window seal 6, in turn, also has a heat-conducting layer W2, for example made of copper, applied to its outer surface A2. The outside window seal 6' has a heat-conducting layer W2 (for example made of copper) on its inner surface B1. The heat-conducting layers W1, W2 are applied to the radiation source 2 and the window seal 6, 6', for example, by means of an adhesive.When the vehicle window 100 is closed, the heat-conducting layers W1 of the radiation source 2 are in direct spatial contact with the heat-conducting layers W2 of the inside and outside window seals 6, 6'. If the vehicle window 100 is opened, the radiation source 2 and thus also the heat-conducting layers W1 are removed from the window seal 6, 6'. This happens, for example, when the vehicle window 100 is moved downwards, so that the radiation source 2 moves vertically to the vehicle roof deeper into the vehicle door 101. The heat loss generated during operation of the radiation source 2 can be effectively transferred via the heat-conducting layers W1, W2 to the inside window seal 6 and the outside window seal 6', thus warming them up. This largely prevents the window seal 6, 6' from icing over, preventing the vehicle window 100 from becoming immobilized by ice.The heat-conducting layers W1, W2 can also be roughened on their surfaces, especially those in contact with another heat-conducting layer W1, W2. This increases the surface area and thus the heat transfer.

[0095] Fig. 5c shows an enlarged section Z' of the edge region of the vehicle window 100 adjacent to the upper edge O. The edge surface at the upper edge O is preferably ground and covered with the IR-ray-reflecting layer 4 according to the invention up to the edge-grinding boundary G. It is possible (not shown) that the IR-ray-reflecting layer 4 is also formed on the window surface I and / or II in an edge region of less than 10 mm starting from the edge-grinding boundary G.

[0096] Figure 6 shows a cross-section of a vehicle window according to the invention in a configuration as a composite pane 200 in which a first pane 1 of the embodiment according to the invention shown in Figure 1a is arranged as an outer pane facing the environment 8 and is connected to a second pane 11 as an inner pane via a thermoplastic intermediate layer 12. The radiation source 2 is arranged in a protected manner at the lower edge U of the pane 1 and in a holder H of the composite pane 200.

[0097] In an embodiment not shown, both panes 1 and 11 of the composite pane 200 can be formed with one or more radiation sources 2 and with an IR radiation-reflecting layer 4. The IR radiation-reflecting layer 4 can also extend as a common layer over the edge surface of the composite pane 200, which can simplify the manufacturing process. The radiation sources 2 on the inner and outer panes 1, 11 can preferably be controlled, switched, and operated independently of one another. Thus, if necessary, only one or both panes 1 and 11 can be heated, enabling energy-saving operation.

[0098] The composite pane 200 can furthermore have a conventional known structure and can implement the invention in a manner analogous to that in previously described embodiments.

[0099] The outer pane 1 and the inner pane 11 are preferably made of soda-lime glass. However, the panes 1, 11 can also be made of other types of glass (e.g., borosilicate glass, quartz glass, aluminosilicate glass). The thickness of the outer pane 11 and the inner pane 1 can vary widely. Preferably, panes 1, 11 with a thickness in the range of 0.5 mm to 10 mm, more preferably 1 mm to 5 mm, are used.

[0100] The thermoplastic intermediate layer 12 comprises at least one layer of a thermoplastic bonding material, which preferably contains ethylene-vinyl acetate (EVA), polyvinyl butyral (PVB), or polyurethane (PU), or mixtures or copolymers or derivatives thereof, particularly preferably PVB. The intermediate layer 12 is typically formed from at least one thermoplastic film. The thickness of the film is preferably from 0.3 mm to 2 mm, with standard thicknesses of 0.36 mm and 0.76 mm being particularly common. The intermediate layer 12 can also comprise multiple layers of thermoplastic material and, for example, be formed from multiple polymer films arranged flatly one above the other.

[0101] Figure 7 shows an absorption spectrum of water in the liquid state. The diagram shows that water molecules, for example, have a particularly high absorption coefficient at a wavelength of approximately 3 pm. In a preferred embodiment, a radiation source in the IR wavelength range from A = 1.4 pm to A = 1.6, particularly preferably from A = 2.9 to A = 3.1 pm, is used for the heated vehicle window, since the absorption and excitation of the water molecules, and thus the resulting heating and evaporation, is particularly high in this preferred wavelength range. Preferably, the optical fiber simultaneously exhibits a transmission in the wavelength range from A = 2.9 to A = 3.1 pm of over 70%, particularly at approximately A = 3.0 pm of approximately 85%, so that the radiation energy can be used efficiently for defrosting and evaporating water in the corresponding areas. List of reference symbols:

[0102] 1 disc (optical fiber)

[0103] 2 radiation source

[0104] 3 IR radiation

[0105] 3a unused portion of IR radiation

[0106] 3b IR radiation 3a, which is reflected by the IR-ray reflecting layer 4

[0107] 4 IR-ray reflecting layer

[0108] 5 IR mirror layer (coupling layer)

[0109] 6 inside window seal

[0110] 6' outside window seal

[0111] 7 Protective layer

[0112] 8 external environment

[0113] 9 Vehicle interior

[0114] 10 Water (condensate, ice)

[0115] 11 second disc

[0116] 12 thermoplastic intermediate layer

[0117] 100 vehicle windows

[0118] 101 Vehicle door (vehicle)

[0119] 200 vehicle composite windows

[0120] I outer surface of the pane 1

[0121] II Interior surface of pane 1

[0122] III outer surface of the second disc 11

[0123] IV Interior surface of the second pane 11

[0124] A1 Inner surface of the inside window seal 6

[0125] A2 Outer surface of the inside window seal 6

[0126] B1 Inner surface of the outside pane seal 6'

[0127] B2 Outer surface of the outside window seal 6'

[0128] W1 thermally conductive layer

[0129] W2 heat-conducting layer of the window seal 6, 6'

[0130] G Edge grinding limit

[0131] H Disc holder 51 first side edge

[0132] 52 second side edge

[0133] O Top edge (roof edge)

[0134] U Lower edge (motor edge)

[0135] XX' cutting line

[0136] Z, Z' Enlarged section

Claims

Patent claims 1. Vehicle window (100), comprising at least one window (1) as an optical waveguide with an outside surface (I) and an inside surface (II), and a circumferential edge surface (S1, S2, II, O), and at least one radiation source (2) for radiation (3) in the IR wavelength range, characterized in that the radiation source (2) emits radiation in an IR wavelength range of A = 1.3 pm to 3.5 pm and is arranged so as to be connected to the window (1) that the IR radiation (3) emitted by the radiation source (2) is coupled into the window (1) in an entry region and an IR radiation-reflecting layer (4) is arranged at least in one passive exit section for the IR radiation (3) of the radiation source (2) on the circumferential edge surface (S1, S2, II, O).

2. Vehicle window (100) according to claim 1, characterized in that the radiation source (2) emits IR radiation (3) in an IR wavelength range from A = 1.4 pm to A = 3.3 pm, preferably in a range from A = 1.4 pm to A = 3.1 pm.

3. Vehicle window (100) according to claim 1 or 2, characterized in that the radiation source (2) emits IR radiation (3) in an IR wavelength range from A = 1.4 pm to A = 1.6 pm, preferably 1.45 pm to 1.55 pm or in an IR wavelength range from 1.9 pm to 2.1 pm, preferably 1.95 pm to 2.05 pm, or from A = 2.9 to A = 3.1 pm.

4. Vehicle window (100) according to one of claims 1 to 3, characterized in that the IR-ray-reflecting layer (4) is a layer based on a metal or a metal alloy, preferably based on silver, chromium, aluminum, nickel, tungsten, or a transparent coating based on an electrically conductive oxide, preferably made of indium tin oxide.

5. Vehicle window (100) according to one of claims 1 to 4, characterized in that the IR radiation-reflecting layer (4) covers the circumferential edge surface (S1, S2, II, O) to at least 80%, preferably completely, and / or additionally extends over an edge region, starting from the circumferential edge surface (S1, S2, II, O) of less than 10 mm, to the outside surface (I) and / or the inside surface (II) of the window (1).

6. Vehicle window (100) according to one of claims 1 to 5, characterized in that the IR-ray reflecting layer (4) has a thickness of 5 nm to 50 nm.

7. Vehicle window (100) according to one of claims 1 to 6, characterized in that on the side of the IR-ray-reflecting layer (4) facing away from the window (1), a protective layer (7), preferably made of polymeric material based on polyacrylates, polyoximes, alkyd resins, polyurethanes or mixtures thereof, or a protective layer (7) made of diamond-like, amorphous carbon, is arranged.

8. Vehicle window (100) according to one of claims 1 to 7, characterized in that the radiation source (2) comprises at least one LED, OLED and / or a laser, preferably an LED.

9. Vehicle window (100) according to one of claims 1 to 8, wherein the radiation source (2) is arranged on at least a portion of the circumferential edge surface (S1, S2, O, U) of the window (1).

10. Vehicle window (100) according to one of claims 1 to 8, wherein the radiation source (2) is arranged in a recess of the window (1).

11. Vehicle window (100) according to one of claims 1 to 10, wherein a second IR mirror layer (5), preferably in the form of a prism film, is applied to a surface (I) or (II) of the window (1) and wherein the radiation source (2) is arranged relative to the second IR mirror layer (5) in such a way that the emitted IR radiation (3) can be coupled into the window (1) by means of reflection at the second IR mirror layer (5).

12. Vehicle window (100) according to one of claims 1 to 11, characterized in that the radiation source (2) is applied to the first surface (I) or the second surface (II) of the window (1) by means of an optically clear adhesive which is in the form of an oblique wedge.

13. Vehicle window (100) according to one of claims 1 to 12, characterized in that the vehicle window (100) comprises a second pane (11) which is congruently connected to the first pane (1) via a thermoplastic intermediate layer (12).

14. A method for producing a vehicle window (100) according to one of claims 1 to 13, wherein (A) the radiation source (2) is arranged connected to the pane (1) in such a way that the IR radiation (3) is coupled into the pane (1), and (B) an IR radiation-reflecting layer (4) is formed in at least one passive exit section on the circumferential edge surface (S1, S2, U, O).

15. Vehicle component comprising a vehicle window (100) according to one of claims 1 to 13, characterized in that at least one first heat-conducting layer (W1, W2) is applied to the radiation source (2), which is in contact with a window seal (6, 6') or can be brought into contact.

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