Coated panel with communication window

Abstract

The invention relates to a coated panel (100) with a communication window, comprising:-a panel (1),-a coating (2) on a surface (II) of the panel (1), the coating (2) having at least one communication area (K) and a base area (B), wherein the coating (2) has at least one dielectric layer (3) in a communication region (K) and at least one dielectric layer (3) in a base region (B) and an electrically conductive layer (4) above the dielectric layer (3), and wherein the communication region (K) has fewer layers than the base region (B) and no electrically conductive layer (4), and wherein each layer of the coating (2) is a thin layer.

Description

[0001] The present invention relates to a coated panel having a communication window, to a method for producing such a coated panel, and to the use thereof.

[0002] Panels having a metal layer or a metal-containing layer are widely used in architectural glazing and in vehicle glazing. These metal-based coatings influence the transmission, reflection and absorption behavior of electromagnetic radiation. Electrically conductive coatings can be used to heat the panel.

[0003] The use of metal-containing coatings as a solar-protection coating and as a heat radiation-reflecting layer (low-E layer) is known. Solar-protection coatings reflect a large proportion of incident solar radiation, especially in the infrared range, which leads to reduced heating of the interior in summer. When a low-E layer is applied to the interior-facing surface of a panel, the low-E layer reduces the emission of long-wave heat radiation from a heated panel to the interior. In winter, when the outside temperature is low, heat radiation from the interior to the outside environment is prevented. Such layers are known, for example, from WO 2022248260 A1, DE 202021102267 U1 and WO 2022161770 A1.

[0004] However, panels having a metal-containing coating also have disadvantages. For example, radio-frequency radiation is absorbed by many metal-containing coatings. This significantly impairs the functioning of many sensors, navigation, telecommunications or radio devices. To solve these problems, it is often necessary to remove at least a portion of the metal-containing coating. In the case of electromagnetic radiation in the radio-frequency range, for example FM, AM, UHF, VHF, DAB, mobile communication in the GSM 900, GSM 1800 and UMTS frequency bands, satellite-based navigation (GPS) or microwave radiation, at least a net- or grid-like decoating is required. The grid meshes must have a line spacing that is significantly smaller than the relevant wavelength of the desired electromagnetic radiation. For this purpose, the metal-containing coating is removed, for example, in the form of lines using a suitable laser. Since only a small portion of the metal-containing coating needs to be removed, the infrared radiation absorption effect is largely preserved. Layers that are at least partially transparent to radio-frequency radiation are known, for example, from WO 2004051869 A2 and US 6730389 B2.

[0005] EP 3034295 A1, WO 2014033007 A1 and WO 2012066324 A1 disclose panels having a communication window, in which the metal-containing coating is removed by means of a laser beam. In this case, the coating is completely removed in the area intended for decoating to produce the communication window. The decoating process is energy- and time-intensive.

[0006] DE202021100791U1 discloses a glass panel, typically used for vehicle panels, having a black marking in an edge region, wherein a functional coating of the glass panel is applied to the panel outside the edge region. The black marking is typically made of an enamel with glass frit, which, when applied to the glass, typically has a thickness of well over 10 μm. Such a thickness of the black marking is usually necessary to achieve sufficient panel opacity in the desired area.

[0007] The present invention is based on the object of providing a coated panel with a communication window that can be produced in a cost-effective, sustainable, and efficient manner. It is also an object to provide an improved method for producing a coated panel with a communication window. The method should be implementable in various ways and should allow the creation of communication windows of any shape and size.

[0008] This object is achieved by a coated panel according to independent claim 1 and by a method according to independent claim 10. Preferred embodiments are apparent from the dependent claims.

[0009] A panel coated according to the present invention and having a communication window comprises a panel and a coating on a surface of the panel. The coating comprises at least one communication region and at least one substrate region. The coating comprises at least one dielectric layer in the communication region, at least one dielectric layer in the substrate region, and a conductive layer above the dielectric layer. The communication region has fewer layers than the substrate region, preferably at least one layer fewer, and no conductive layer. This means that there is no conductive layer in the communication region of the coating.

[0010] The communication area is the same layer as the dielectric layer in the substrate area. The dielectric layer is preferably in direct contact with the panel, that is, it is the first layer on the panel. In the communication area and the substrate area, additional layers can be arranged above the dielectric layer, wherein the additional layers arranged in the communication area and the substrate area are preferably all arranged below the conductive layer in the substrate area. In the substrate area, layers can also be arranged above the conductive layer. In addition, more than one conductive layer, preferably 2, and particularly preferably 3 conductive layers can be arranged in the substrate area. If additional layers are arranged in the communication area in addition to the dielectric layer, the additional layers are preferably arranged in the substrate area in exactly the same order without any additional intermediate layers. In other words, the layers arranged in the communication area are preferably arranged in the same form and order as in the substrate area, except that the substrate area has at least a conductive layer above these layers. This has the advantage that the communication area can be created simply by removing the layers above the substrate area (including the conductive layer).

[0011] In the context of the present application, the communication area of the panel refers to an area which can act as a kind of communication window. The panel is thus more transparent to high-frequency radiation having a frequency of, for example, 1 to 3 GHz in the communications range than in the base range. The communications range is thus able to receive radiation which is required for the proper use of, for example, sensors, navigation, telecommunications or radio equipment. At least one dielectric layer in the communication area does not reduce the transparency of the high-frequency radiation to a great extent. In order to create the communication window, the coating does not have to be completely stripped in any area. This is a great advantage of the present application.

[0012] Preferably, the coated panel is more transparent in the communication area than in the base area to radiation having a wavelength of greater than 1 pm, particularly preferably greater than 1.2 pm, particularly greater than 1.5 pm.

[0013] In the context of the present application, a dielectric layer is particularly understood to mean a layer made of a material having an electrical conductivity (reciprocal specific resistance) of less than 10 -4 S / m. On the other hand, a conductive layer is particularly a layer made of a material having an electrical conductivity of greater than 10 4 S / m.

[0014] Additional dielectric layers can be arranged in the base area. Due to the dielectric layers, for example, an aesthetically pleasing coating having a specific color, or a coating having antireflection properties in the visible spectral range or having reflection properties in the ultraviolet spectral range (UV range) or in the infrared spectral range (IR range) can be achieved. Further dielectric layers can also be arranged in the base area and in the communication area, wherein these layers preferably have no or largely no reflection properties in the ultraviolet spectral range (UV range) or in the infrared spectral range (IR range). Particularly preferably, one, preferably two, particularly preferably three further dielectric layers are arranged in the base area above the conductive layer. The further dielectric layers can influence the reflection properties, the color and the transmission of the panel. The desired properties can thereby be adjusted via the further dielectric layers.

[0015] In a preferred embodiment of the present application, only the dielectric layer according to the present application is arranged in the communication area of the coating, without further dielectric layers, in particular without further layers. The communication area is preferably formed by removing all layers by means of a laser beam, wherein all layers other than the dielectric layer according to the present application are removed. The communication area of the coated panel according to the present application is essentially as suitable for use as a communication window as a completely stripped area of an ordinary panel.

[0016] The further dielectric layers can for example comprise layers with a high refractive index and layers with a low refractive index arranged alternately, wherein the reflective or anti-reflective properties are caused by interference effects. The optically high-refractive layers have a refractive index of for example at least 1.8, preferably at least 2.0. The optically low-refractive dielectric layers have a refractive index of for example less than 1.8, preferably less than 1.6.

[0017] The common dielectric layers constituting the dielectric layer and possibly the further dielectric layers are based for example on silicon nitride, silicon-metal mixed nitride (for example silicon zirconium nitride), titanium oxide, aluminum nitride, aluminum oxide, tin oxide, zinc oxide, tin-zinc mixed oxide, zirconium nitride, zirconium oxide or silicon oxide. If the layers of the coating are formed on the basis of one material, this means in the context of the present application that the layers consist mainly of this material, i.e. in a proportion of at least 50% by weight, preferably at least 70% by weight, particularly preferably at least 90% by weight. The layers can also contain in particular dopants and / or impurities, preferably in a proportion of at most 10% by weight. The oxides and nitrides mentioned can be stoichiometric, substoichiometric or superstoichiometric in terms of oxygen or nitrogen content.

[0018] Further electrically conductive layers can also be arranged in the substrate region. The electrically conductive layers and possibly any further electrically conductive layers are preferably formed on the basis of a metal, for example silver, or on the basis of a transparent conductive oxide (TCO), for example indium tin oxide (ITO). If a plurality of electrically conductive layers is present, the adjacent electrically conductive layers are preferably separated from one another by at least one dielectric layer. The electrically conductive layers are in particular functional layers which provide the coating with a function. For example, the electrically conductive layers can be IR-reflective in order to provide the coating with an IR-reflective function. The electrically conductive layers can also have emissivity-reducing properties. Likewise, the electrically conductive layers can provide the coating with a heating function when the coating is electrically contacted in order to pass a heating current through the coating.

[0019] Preferably, the communication area is formed by removing the uppermost layer or layer sequence of the coating, such that the layer or layer sequence missing in the communication area compared to the base area of the coating is the uppermost layer or layer sequence in the base area of the coating. If only a single layer is removed, this layer is the electrically conductive layer and thus also the uppermost layer. If a plurality of layers (layer sequence) is removed, all layers to be removed are adjacent to each other and contain the uppermost layer (and thus form the uppermost layer sequence). All layers to be removed are thus located above all remaining layers. The terms "uppermost layer (sequence)" and "above" refer to the order of the layers starting from the panel: the uppermost layer is the layer having the greatest distance from the panel surface, and a layer is arranged above another layer if it has a greater distance from the panel surface. Thus, a second layer arranged below a first layer is a layer having a smaller distance from the panel surface than the first layer. "Below" or "above" a layer does not necessarily mean that there must be a direct spatial contact between the layers. For example, it is possible that a second layer is arranged above a first layer, but further layers are also arranged between the second layer and the first layer.

[0020] The coating is preferably transparent to visible light radiation (380 nm to 780 nm) in the base area and in the communication area, such that observation through it is possible. This applies in particular if the panel is also transparent and the article is intended as a window panel or part of such a window.

[0021] In a preferred embodiment of the application, the communication area extends in the form of a grid on the panel when viewed from above. The shape of the grid means that the communication area extends in a grid-like manner on the panel. Said communication area is preferably an area displaying grid lines. The area arranged between the grid lines of the communication area is preferably a base area. In particular, the communication area and the base area extend over the entire coated surface of the panel. Said grid-like shape of the communication area is preferably produced by ablation using a laser beam. The grid-like communication area forms, for example, a panel structured in a mesh and appears slightly brighter on the real panel than the surrounding coating (base area), in particular in grazing light or reflection.

[0022] The one or more communication areas together preferably extend over less than 20 %, particularly preferably less than 15 %, and in particular less than 10 % of the surface of the panel. The one or more base areas preferably extend over at least 60 %, particularly preferably at least 80 %, in particular at least 90 % of the surface of the panel. It is particularly preferred that the communication area and the base area (or the number of communication areas and / or the number of base areas) together extend over the entire surface of the panel, particularly preferably with the exception of a circumferential linear edge region of the panel, which extends along and adjacent to the edge of the panel. Such edge de-coating is particularly useful when the panel is part of a laminated panel and the coating needs to be protected from external influences.

[0023] According to the application, the individual layers of the coating, i.e. the dielectric layers and / or the electrically conductive layers, are thin layers, which are understood to be layers having a thickness of less than one micrometer. They are deposited flat on top of one another in the form of a layer stack. The layer thickness of the individual layers is preferably from 10 nm to 200 nm, the total thickness of the coating being, for example, from 50 nm to 1000 nm. Methods for measuring the thickness of thin layers are known to the person skilled in the art. The thickness of the individual layers can be determined using common methods for determining the layer thickness of thin layers, such as spectroscopic reflectometry, confocal microscopy, white light interferometry or ellipsometry. These methods enable non-destructive measurement, and corresponding measurement devices are commercially available. Ellipsometers are commercially available, for example from Sentech. White light interferometry, profilometry, for example confocal profilometry, or ellipsometry is preferably used.

[0024] In a preferred embodiment of the application, the at least one electrically conductive layer of the base area has a layer thickness of more than 10 nm, preferably more than 15 nm and particularly preferably more than 20 nm. With such a layer thickness, there is a good effect of the reduction of the emissivity. The solar radiation reflection effect is also improved in the case of a layer thickness of more than 10 nm. With such a layer thickness, in particular, the electrically conductive layer is based on a transparent conductive oxide (TCO) - for example indium tin oxide (ITO).

[0025] The shape of the communication area(s) can be chosen arbitrarily, as can the shape of the base area(s). This enables any kind of design to be created.

[0026] There can be a single, continuous base area, in which a single communication area or a number of communication areas are formed as islands. Each communication area is completely surrounded by the base area. At least one communication area can, for example, have the shape of a two-dimensional geometric figure. If there is more than one communication area, the communication areas can have the same shape or different shapes. The communication areas can be distributed in the form of a regular pattern or irregularly.

[0027] However, other arrangements of the communication area(s) and the base area(s) can also be chosen. For example, a stripe pattern or a chessboard pattern can be displayed. Irregular patterns are also possible.

[0028] The panel is preferably made of transparent glass, in particular soda-lime glass. However, it can also be made of other glasses, such as borosilicate glass, quartz glass, aluminosilicate glass, or transparent plastics, such as polymethyl methacrylate or polycarbonate. The panel further has an outer peripheral edge. The thickness of the panel can vary widely. Preferably, panels having a thickness in the range of 0.8 mm to 5 mm, preferably 1.4 mm to 2.5 mm, such as those having a standard thickness of 1.6 mm or 2.1 mm, are used. The panel can be non-tempered, partially tempered or tempered. The prestress can be thermal or chemical.

[0029] The panel can have any three-dimensional shape. Preferably, the panel has no shadow zones, thereby enabling efficient coating by cathode sputtering. The panel is preferably planar or slightly or significantly curved in one or more spatial directions. The panel is preferably flat, but can in principle also be cylindrical or spherically curved. The coating according to the application can also be applied to a flat panel, and the panel according to the application can subsequently be curved.

[0030] According to the application, one of the surfaces (main faces) of the panel is provided with a coating. In principle, both surfaces of the panel can be provided with a coating.

[0031] The coated panel according to the application can also be a component of a laminated panel. The coated panel is, for example, an outer panel or an inner panel of a laminated panel, but is preferably an inner panel. The term inner panel means a panel of the laminated panel which is intended to be positioned closer to the interior than the other panel(s) of the laminated panel. An outer panel means a panel of the laminated panel which is intended to be positioned closer to the exterior environment than the other panel(s) of the laminated panel. The inner panel and the outer panel are preferably connected to each other via a thermoplastic intermediate layer.

[0032] The coating is preferably applied over the entire surface of the panel, so that the entire surface is covered with the coating. The difference between the base area and the communication area can be achieved, for example, by removing individual layers of the surface in certain areas, for example by laser ablation. However, in principle, it is also conceivable to achieve the difference between the communication area and the base area by masked and unmasked areas. In other words, for example, a dielectric layer is applied over the entire surface of the panel, the areas intended to serve as communication areas are then masked and further layers are then applied, wherein the areas intended to serve as communication areas are then again uncovered. However, the removal of individual layers is clearly preferred over this variant, as it is more efficient and cost-effective.

[0033] In an advantageous embodiment, the coating is deposited on the surface of the panel by vapour deposition, for example by chemical vapour deposition (CVD), plasma-enhanced chemical vapour deposition (PECVD) or atomic layer deposition (ALD). Physical vapour deposition (PVD), for example evaporation deposition, is particularly preferred, cathode sputtering ("sputtering") and in particular magnetic field-assisted cathode sputtering ("magnetron sputtering") is very particularly preferred.

[0034] In an advantageous embodiment, after the coating has been applied to the panel, the communication area is formed by removing at least the electrically conductive layer by means of a laser beam. During the laser processing, at least the electrically conductive layer and all layers located thereabove are preferably removed from the communication area, while at least one dielectric layer is retained in the communication area. Thus, the communication area can be obtained by removing at least the electrically conductive layer and possibly any layers arranged above the electrically conductive layer by means of a laser beam. Preferably, all layers in the communication area except the dielectric layer are removed using a laser beam. Forming the communication area by removing layers using a laser beam is a highly efficient and cost-effective method. Since not all layers have to be removed, a shorter processing time is required compared to panels which are typically de-coated using a laser beam. Panels which are partially de-coated using a mechanical method cannot be distinguished visually from other manufacturing methods with the same level of accuracy and can therefore be clearly distinguished from production using a laser beam. Forming the communication area and the base area by means of masking and unmasking methods results in very homogeneous layers which, due to the manufacturing method, only contain the applied layers. However, in the case of partial de-coating using laser radiation, small residues of the removed layers can remain, which significantly affect the optical properties of the panel. Thus, de-coating produces fewer homogeneous layers than masking and unmasking methods, which means that the panels can be clearly distinguished from one another.

[0035] The application further extends to a method for manufacturing a coated panel. The method is preferably carried out in the specified order.

[0036] (A) In a first step, a panel is provided.

[0037] (B) In a second step, at least one dielectric layer and one electrically conductive layer are arranged as a coating on the surface of the panel in the following order.

[0038] (C) In a third step, at least the electrically conductive layer is removed in a communication area of the coating, wherein at least the dielectric layer is retained in the communication area and the electrically conductive layer is not removed in at least one base area of the coating. Preferably, no layers are removed in the base area.

[0039] In a second step (B), further layers, preferably further dielectric layers, in addition to the electrically conductive layer, can be arranged after or before the arrangement of the dielectric layer and before the arrangement of the electrically conductive layer. After the electrically conductive layer, further layers, both further electrically conductive layers and dielectric layers, can also be arranged, wherein in a third step (C) at least all electrically conductive layers are removed in the communication area.

[0040] Preferably, all applied layers except the dielectric layer are removed in the communication area. This means that only one dielectric layer remains in the communication area of the panel, while all other layers are removed. In this case, the panel in the communication area is particularly transparent to high-frequency radiation.

[0041] In a particularly preferred embodiment of the application, the dielectric layer is the layer closest to the panel. This means that the dielectric layer is preferably applied directly to the surface of the panel, without any further layers being arranged between the dielectric layer and the panel.

[0042] In a particularly preferred embodiment of the application, the electrically conductive layer, preferably all layers except the dielectric layer, is removed in at least the communication area of the panel by means of laser radiation. The laser radiation is preferably moved (once or several times) over at least one communication area, wherein at least the electrically conductive layer is removed by ablation (laser ablation). The movement speed of the laser radiation is preferably 10 mm / s to 100 m / s, particularly preferably 100 mm / s to 50 m / s, very particularly preferably 1 m / s to 25 m / s, in particular 3 m / s to 10 m / s.

[0043] With a stationary laser and a stationary panel, the laser radiation can be moved over at least one communication area by means of a laser scanner, wherein the laser radiation is suitably moved by means of a movable mirror system. However, alternatively, the laser itself can also be moved while the panel is stationary, or the panel can be moved while the laser is stationary.

[0044] After the second method step, the coated surface of the panel can face the laser. If the panel is (mainly) transparent to the laser radiation (in particular in the case of a glass panel), the coated surface can alternatively face away from the laser, and the laser radiation can be directed through the panel onto the coating. In both cases, the laser radiation is preferably focused on the surface of the panel having the coating. The extent (diameter) of the laser spot on the coating is preferably 25 μm to 250 μm, particularly preferably 40 μm to 180 μm.

[0045] Preferably, laser radiation in the UV range, the visible range or the IR range of the electromagnetic spectrum is used. The wavelength of the laser radiation is preferably from 200 nm to 2000 nm, particularly preferably from 250 nm to 1100 nm, for example from 355 nm to 1064 nm. Particularly good results are thereby achieved. For example, solid-state lasers, such as Nd:YAG lasers or Yb:YAG lasers, can be used, which can be frequency-doubled, frequency-tripled or frequency-doubled twice, as required. Such lasers are widely used in industry, are relatively inexpensive and efficient. Alternatively, diode lasers, excimer lasers, gas lasers or dye lasers can also be used.

[0046] The laser is preferably operated in shelled mode. The pulse length of the laser is preferably in the femtosecond or nanosecond range. The pulse length is preferably no more than 1 ns, particularly preferably no more than 10 ps. The pulse length is very particularly preferably from 200 fs to 10 ps, in particular from 500 fs to 1 ps. Particularly good results are thereby achieved. Such short pulses minimize thermal stress in the laser processing environment, enabling thin layers and even heat-sensitive materials to be processed. The repetition frequency of the laser pulses is preferably from 10 kHz to 1000 kHz, particularly preferably from 50 kHz to 400 kHz. The pulse energy is preferably from 200 nJ to 500 μJ, particularly preferably from 250 nJ to 250 μJ, very particularly preferably from 150 μJ to 250 μJ.

[0047] The output power of the laser is preferably from 10 W to 200 W, preferably from 40 W to 150 W.

[0048] The laser radiation used can be adapted to the coating to be processed in order to achieve efficient ablation of at least the electrically conductive layer, and possibly also of further layers, in the communication region. This is achieved in particular by selecting the wavelength, the laser power, the pulse energy and the pulse length. All these variables have an influence and can be selected accordingly. In addition, the effectiveness of the ablation can also be adjusted by appropriately selecting the movement speed of the laser radiation and the movement frequency of the laser radiation.

[0049] As an alternative to the method steps (B) and (C), it is also possible to first coat the panel on one surface with at least one dielectric layer in the communication region and in the base region and subsequently mask the communication region, for example by means of a cover film. Subsequently, the surface of the panel is coated with at least an electrically conductive layer, wherein the masking prevents the panel from being coated with the at least electrically conductive layer in the communication region. The panel is coated with the at least electrically conductive layer in the base region. In a subsequent method step, the masking is removed from the coated panel.

[0050] The invention also comprises the use of the coated panel in the field of vehicles or construction, in particular as a window panel of a vehicle, a building or a room or as a component of such a window panel or as a facade panel of a building, furniture or other household articles.

[0051] The invention is explained in more detail with reference to the drawings and exemplary embodiments. The drawings are a schematic presentation and are not true to scale. The drawings do not limit the invention in any way. In the drawings: Figure 1 is a top view of an embodiment of a coated panel according to the invention; Figure 2 is a cross-sectional view through the panel along A-A' of Figure 1 ; Figure 3 is a cross-sectional view through the panel during the production of the panel Figure 1 and 2 employing an embodiment of the method according to the invention; Figure 4 is a top view of another embodiment of a panel according to the invention; and Figures 5-7 shows the attenuation as a function of the radiation frequency, shown in the graphs of inventive examples 1 to 3 each with a comparative example.

[0052] Figure 1 and Figure 2 each show details of an exemplary coated panel 100 according to the invention. It is a panel 1 made of soda-lime glass, for example, which is coated on the surface II with a coating 2.

[0053] The panel 1 has a thickness of, for example, 2.1 mm. The panel 1 is intended to be used as an interior panel of a laminated panel and is connected to an exterior panel via a thermoplastic intermediate layer. The laminated panel is provided, for example, as a roof panel of a motor vehicle. The panel 1 has two main faces intended for viewing through the glass panel, namely a first surface I and a second surface II, and a circumferential edge face extending between them.

[0054] The coating 2 has a number of base regions B arranged within a grid-like structure of communication regions K. In the plan view of the panel 100, the communication regions K are in the form of strips from the upper edge of the panel 1 to the lower edge of the panel 1 and from one side edge of the panel 1 to the other side edge. The side edges connect the upper edge and the lower edge, so that the side edges, the upper edge and the lower edge constitute the entire circumferential edge of the panel 1. The strips of communication regions K form a grid shape in the overall view. One or more communication regions K and one or more base regions B can be designed essentially as desired. The communication regions K are not necessarily arranged in the form of a regular pattern, as shown by way of example in the figures.

[0055] The coating 2 is designed as a stack of thin layers and is designed differently in the base region B than in the communication region K. In the base region B, the coating 2 has a total of five layers: a first dielectric layer 3, a second dielectric layer 3.2, an electrically conductive layer 4, a third dielectric layer 5 and a fourth dielectric layer 6 arranged in the specified order starting from the second surface II of the panel 1. However, the electrically conductive layer 4, the second dielectric layer 3.2, the third dielectric layer 5 and the fourth dielectric layer 6 are missing in the communication region K, so that the coating 2 in the communication region K is formed only by the first dielectric layer 3. The exemplary layer sequence of the coating 2 as well as the materials and layer thicknesses are summarized in Table 1.

[0056] Table 1 .

[0057] Due to the alternating sequence of the optically high-refractive layers 2.1, 2.3 based on silicon nitride (Si3N4) and the optically low-refractive layers 2.2, 2.4 based on silicon oxide (SiO2), the coating 2 has antireflection properties due to the interference effect. In addition, due to the electrically conductive layer 4 based on indium tin oxide (ITO), the coating 2 in the base region B has a solar radiation reflection effect.

[0058] Since the coating 2 has a significant influence on the appearance of the glass panel, the base region B and the communication region K differ optically from one another, in particular in the degree of reflection and in the color (reflection color). An observer can therefore easily distinguish the communication region K from the base region B at least using suitable optical measuring devices.

[0059] The design shown here is to be understood only as an example. The coated panel 100 according to the application can basically have any type of coating 2 as long as it has an influence on the optical properties of the article. The coating 2 may, for example, also be a solar protection coating with at least one silver layer having reflection properties in the near-IR range or a solar emittance reduction coating (low-emission coating) with an ITO layer having reflection properties in the mid-IR range, in particular in the heat radiation range of the panel 1.

[0060] The number of layers in the base region B and the communication region K is also only exemplary. Alternatively, for example, only the electrically conductive layer 4, the third dielectric layer 5 and the fourth dielectric layer 6 can be missing in the communication region K compared to the base region B.

[0061] Figure 3 A cross section through the coated panel 100 is shown in the three method steps of the method according to the application for its production. Figure 1 and 2 The coated panel 100 is shown in the three method steps of the method according to the application for its production. Figure 3 A) is provided. Subsequently, the coating 2 is applied on the second surface II of the panel 1 Figure 3B). To this end, the layers 3, 3.2, 4, 5, 6 are deposited on the second surface II one after the other, for example by means of magnetic field assisted cathodic sputtering I. Subsequently, the uppermost four layers 3.2, 4, 5, 6 are removed in the communication area K by means of the radiation L of the laser 7. To this end, the radiation L is focused onto the coating 2 by means of a focusing element 8, for example a lens or an objective. Subsequently, the radiation L is moved in the movement direction x over the entire communication area K by means of a laser scanning system, which comprises at least one, usually at least two, movable, in particular tiltable, mirrors 9. The layers 3.2, 4, 5, 6 are removed by laser ablation Figure 3 C).

[0062] The radiation L has a wavelength, for example in the visible spectral range. The laser 7 is, for example, a pulsed Yb:YAG laser which emits at a wavelength of 1030 nm.

[0063] Figure 4 A plan view of a further embodiment of an article according to the application is shown. Here, the communication area K is arranged in a single continuous segment of the panel 1. The communication area K extends in a strip shape from one side edge to the other side edge of the panel 1 and is arranged closer to the upper edge of the panel 1 than to the lower edge of the panel 1. In this embodiment, there is only one base area B. Said base area B extends from one side edge to the other side edge of the panel 1 and is arranged closer to the lower edge of the panel 1 than to the upper edge of the panel 1. The base area B extends, for example, over 80% of the second surface II of the panel 1, wherein the communication area K extends over the remaining second surface II of the panel 1 less the uncoated circumferential edge area of the panel 1.

[0064] Figures 5 to 7 The radiation attenuation (in decibels) of a coated panel 100 according to the application as a function of the radiation frequency is shown, each with a comparative example and without a communication area K. The panels of the comparative examples have a coating over the entire surface of the panel, similar to Figure 1 and 2 the coating 2 present in the base area B. The panels according to the application are delaminated in the same way as the panel 100 shown in Figure 1 and 2 .

[0065] The attenuation is measured using a dedicated transmission measurement device. Two antennas adapted to transmit and receive radiation having a frequency of more than 1 GHz are provided. The first antenna is mounted inside an absorber chamber and is used to receive the radiation. The second antenna is mounted outside the absorber chamber, wherein the first and second antennas are mounted opposite to each other and are separated by a metal wall having an opening, i.e. a hole. The metal wall is a component of the absorber chamber. The absorber chamber thus has an opening exactly between the two antennas. For the measurement, a panel according to embodiments 1 to 3 is applied to the opening, wherein the coated surface of the panel always faces the metal wall. The second antenna emits radiation over the area shown and the first antenna receives the emitted radiation; thus, the attenuation of the radiation by the panel of embodiments 1 to 3 can be determined. The determined attenuation is related to a reference value (zero axis) in which the opening of the metal wall is free, i.e. there is only air between the antennas. The determination of the attenuation is carried out according to ASTM F3057-16. The attenuation of the panel according to the comparative embodiment is simulated. The simulation is carried out using CST Studio Suite 2023. Figures 5 to 7 Figures 5 to 7 The determined attenuation is related to a reference value (zero axis) in which the opening of the metal wall is free, i.e. there is only air between the antennas. The determination of the attenuation is carried out according to ASTM F3057-16. The attenuation of the panel according to the comparative embodiment is simulated. The simulation is carried out using CST Studio Suite 2023.

[0066] The panels of embodiments 1 to 3 are produced by coating and subsequent partial de-coating in the communication area. As shown in Figure 4 the de-coating is carried out using laser radiation. Embodiments 1 to 3 only differ from each other in the speed of movement of the laser. The differences are shown in Table 2: Table 2 .

[0067] The attenuation of all embodiments 1 to 3 is significantly lower than the comparative embodiment in which no partial de-coating occurs in the communication area. The remaining dielectric layers in the communication area of embodiments 1 to 3 have no significant influence on the attenuation of the radiation. Since a complete de-coating is not necessary, the de-coating can thus be carried out at a high speed of movement of the laser. This is a great advantage.

[0068] List of reference signs 1 panel 2 coating 3 layer of coating 2 / first dielectric layer 3.2 layer of coating 2 / second dielectric layer 4 layer of coating 2 / conductive layer 5 layer of coating 2 / third dielectric layer 6 layer of coating 2 / fourth dielectric layer 7 laser 8 focusing element 9 tiltable mirror 100 coated panel ​K communication area of coating 2 B substrate area of coating 2 L radiation of laser 7 I first surface of panel 1 II second surface of panel 1 x direction of movement of radiation L A - A' cutting line.

Claims

1. Coated panel (100) with communication windows, comprising - a panel (1), - a coating (2) on a surface (II) of the panel (1), wherein the coating (2) has at least one communication area (K) and a base area (B), wherein the coating (2) has at least one dielectric layer (3) in the communication area (K) and at least one dielectric layer (3) in the base area (B) and an electrically conductive layer (4) above the dielectric layer (3), and wherein the communication area (K) has fewer layers than the base area (B) and no electrically conductive layer (4), wherein the individual layers of the coating (2) are thin layers.

2. Coated panel (100) according to claim 1, wherein the communication areas (K) extend in the form of a grid on the panel (1) in a top view of the panel (1).

3. Coated panel (100) according to claim 1 or 2, wherein the communication areas (K) extend over less than 20%, preferably less than 15%, particularly preferably less than 10% of the surface (II) of the panel (1).

4. Coated panel (100) according to any one of claims 1 to 3, wherein the electrically conductive layer (4) has a layer thickness of more than 10 nm, preferably more than 15 nm, particularly preferably more than 20 nm in the base area (B).

5. Coated panel (100) according to any one of claims 1 to 4, wherein the communication areas (K) are obtainable by removing at least the electrically conductive layer (4) by means of a laser beam (L).

6. Coated panel (100) according to any one of claims 1 to 5, wherein the electrically conductive layer (4) is formed on the basis of a metal, a metal alloy or a transparent conductive oxide (TCO).

7. Coated panel (100) according to any one of claims 1 to 6, wherein the communication areas (K) are more transparent to radiation having a wavelength of more than 1 pm than the base areas (B).

8. Coated panel (100) according to any one of claims 1 to 7, wherein the base areas (B) have one, preferably two further dielectric layers (5, 6) above the electrically conductive layer (4).

9. Coated panel (100) according to any one of claims 1 to 8, wherein the communication areas (K) have no further dielectric layers (3.2, 5, 6).

10. Method for producing a coated panel (100), wherein (A) a panel (1) is provided, (B) at least one dielectric layer (3) and one electrically conductive layer (4) are arranged as a coating (2) on a surface (II) of the panel (1) in the following order, and (C) at least the electrically conductive layer (4) is removed in a communication area (K) of the coating (2), wherein at least the dielectric layer (3) remains in the communication area (K), and the electrically conductive layer (4) is not removed in at least one base area (B) of the coating (2).

11. Method according to claim 10, wherein the dielectric layer (3) is applied directly to the panel (1) such that it is the layer closest to the panel (1).

12. The method according to claim 10 or 11, wherein in the communication area (K) at least the electrically conductive layer (4), preferably all layers except the dielectric layer (3), are removed by means of laser radiation (L).

13. The method according to claim 12, wherein the laser radiation (L) has a wavelength in the UV range, in the visible range or in the IR range, preferably from 200 nm to 2000 nm.

14. The method according to claim 12 or 13, wherein the laser radiation (L) is pulsed with a pulse length in the range of femtoseconds or nanoseconds, preferably less than 1 ns.

15. Use of the coated panel (100) according to any one of claims 1 to 7 in the field of vehicles or buildings, in particular as a window panel of a vehicle, a building or a room or as a component thereof, or as glazing of a building, in furniture or other household articles or as a household article.

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