Composite lens with opaque masking area and partial reflective coating

Description

[0001] The invention relates to a composite disc with a transparent viewing area and an opaque masking area, and its use.

[0002] Laminated glass is commonly used as glazing in the automotive and architectural sectors. It consists of an outer pane and an inner pane bonded together by a thermoplastic interlayer. Various functional elements are often embedded in this interlayer, giving the laminated glass a desired function. Examples of such functional elements include IR-reflective and / or heated coatings. Another example is functional elements with electrically controllable optical properties, such as SPD functional elements ( suspended particle device ), PDLC functional elements ( polymer dispersed liquid crystal) or electrochromic functional elements. The optical properties of such functional elements and the laminated glass panes equipped with them, in particular their light transmission or light scattering, can be controlled by an applied electrical voltage.

[0003] The edges of functional elements typically do not extend to the edges of the laminated glass, ensuring that the functional elements are securely embedded within the laminated glass and protected from corrosion and damage. If the edge of the functional element were visible through the laminated glass, it would be visually distracting and detract from the aesthetic appeal of the laminated glass. This is especially true for functional elements that require electrical contact, such as heated layers or functional elements with electrically controllable optical properties. Electrical contact is generally achieved using busbars and electrical cables, which should also be concealed from view.It is therefore common practice to provide the laminated glass with an opaque masking area, typically around a peripheral edge, which effectively conceals the side edge of the functional element and any electrical contacts. The masking area is typically formed by an opaque, usually black, covering print on the outer and inner glass panes. For an example, see WO2017157626A1.

[0004] WO2020094324A1 and WO2014174308A1 also reveal composite discs with embedded functional elements and opaque masking areas.

[0005] In the automotive sector, such opaque masking areas for windshields, rear windows, and roof windows have long been standard practice to protect the adhesive used for installation from UV radiation. However, masking areas are not common on other types of glass, such as vehicle side windows or building glazing, and therefore appear unusual and visually unappealing. Consequently, there is a need for laminated glass with opaque masking areas that are aesthetically pleasing and perceived as less intrusive.

[0006] Printed semi-transparent reflective coatings containing metal oxides are known from the subsequently published international patent applications WO2022117955A1 and WO2022073894A1.

[0007] The present invention is based on the objective of providing an improved composite disc with a functional element, a transparent viewing area and an opaque masking area, in which the masking area is aesthetically designed.

[0008] The problem is solved by a composite disk according to independent claim 1. Preferred embodiments are set forth in the dependent claims.

[0009] The composite pane according to the invention comprises at least one outer pane and one inner pane, which are bonded together via a thermoplastic intermediate layer. The composite pane is intended to separate the interior from the external environment in a window opening (in particular a window opening of a vehicle, but alternatively also a window opening of a building or room). For the purposes of the invention, the term "inner pane" refers to the pane facing the interior. The term "outer pane" refers to the pane facing the external environment. The outer pane and the inner pane each have an outer and an interior surface and a circumferential side edge surface extending between them. For the purposes of the invention, the term "outer surface" refers to the main surface which, in the installed position, is intended to face the external environment.For the purposes of the invention, the term "interior surface" refers to the main surface which, in the installed position, is intended to face the interior. The interior surface of the outer pane and the exterior surface of the inner pane face each other and are connected by the thermoplastic intermediate layer.

[0010] The outer and inner panes are preferably made of glass, particularly preferably of soda-lime glass, as is common for window panes. However, one or both panes can also be made of other types of glass, for example, quartz glass, borosilicate glass, or aluminosilicate glass, or of rigid, clear plastics, for example, polycarbonate or polymethyl methacrylate. The panes can be clear, tinted, or colored. The thicknesses of the outer and inner panes are preferably from 0.5 mm to 5 mm, and particularly preferably from 1 mm to 3 mm, and are independent of each other.

[0011] The intermediate layer is preferably formed from at least one thermoplastic film (bonding film). The at least one film (bonding film) is preferably based on polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), or polyurethane (PU), particularly preferably on PVB. This means that the film contains the said material predominantly (a proportion greater than 50% by weight) and may optionally contain other components, such as plasticizers, stabilizers, or UV or IR absorbers. The thickness of each thermoplastic film is preferably from 0.2 mm to 2 mm, particularly preferably from 0.3 mm to 1 mm. For example, films, especially PVB films, with standard thicknesses of 0.38 mm or 0.76 mm can be used.

[0012] The laminated glass pane according to the invention has an opaque masking area and a transparent viewing area. For the purposes of the invention, the term "masking area" refers to an area of ​​the laminated glass pane through which visibility is not possible. The light transmission of the masking area is preferably essentially 0%. For the purposes of the invention, the term "viewing area" refers to an area of ​​the glass pane that allows visibility through the glass pane and therefore exhibits a certain degree of transparency or at least translucency. The light transmission of the viewing area is preferably at least 10%, and particularly preferably at least 20%. If the functional element according to the invention has electrically controllable optical properties, these specifications refer to the transparent state of the functional element (maximum light transmission and / or minimum light scattering).

[0013] In a typical design, the masking area surrounds the viewing area like a frame. The masking area is thus arranged all the way around the viewing area. Typically, the masking area forms at least part of the edge of the laminated glass. This means that the masking area borders at least a section of the side edge of the laminated glass.

[0014] The masking area is formed by an opaque element positioned on the outside of the functional element. This means that the opaque element is closer to the surrounding environment than the functional element. This prevents the side edge of the functional element from being visible from the outside.

[0015] In a preferred embodiment, the masking area is formed by a masking print on the inner surface of the outer pane facing the interlayer. In other words, the inner surface of the inner pane is provided with the masking print, thus preventing visibility through the laminated glass and creating the masking area. Such masking prints are particularly common in the automotive sector, especially for windshields, rear windows, and sunroofs. The masking print typically contains a pigment and glass frits. The glass frits can be melted, permanently bonding (fusion) the masking print to the glass surface. The pigment provides the opacity of the masking area. The masking print is preferably printed onto the outer pane, particularly using screen printing. The pigment is typically a black pigment, for example, carbon black ( Carbon Black), aniline black, bone black, iron oxide black, spinel black and / or graphite. The masking print preferably has a thickness of 5 µm to 50 µm, particularly preferably 8 µm to 25 µm. The inner disk can optionally also be provided with a masking print, in particular its inner surface.

[0016] Alternatively, the masking area can also be formed by a tinted or colored film in the intermediate layer. For example, at least one thermoplastic bonding film between the functional element and the outer pane can be tinted in the masking area, or a bonding layer can be composed of several sections of different films, with a tinted film used in the masking area and a clear film in the transparent area. Alternatively, an opaque film can also be inserted into the intermediate layer between the functional element and the outer pane.

[0017] Optionally, an additional opaque element can be arranged on the interior side of the functional element within the masking area. This also prevents the view of the functional element's side edge from the inside. For example, the inner pane can also be printed with a cover, especially on its interior surface, or an opaque film can be placed between the functional element and the inner pane.

[0018] In addition to the bonding films, the intermediate layer includes a functional element. In other words, the intermediate layer contains a functional element, is equipped with a functional element, or a functional element is embedded within the intermediate layer. The functional element is thus positioned between the outer and inner panes and may optionally be in direct contact with the surface of the outer and / or inner panes facing the intermediate layer. The functional element is specifically arranged across the surface between the outer and inner panes, essentially parallel to these panes.

[0019] For the purposes of the invention, a functional element is understood to be a planar element or component, in particular a layer- or film-like element or component, which provides the transparent area of ​​the laminated glass with an additional function or property. This can, for example, relate to the color, the effect on electromagnetic radiation, a heating function, or the possibility of electrically controlling the optical properties (in particular the degree of light transmission or light scattering).

[0020] The functional element covers the entire transparent area of ​​the laminated glass pane. This means that the functional element is positioned between the outer and inner panes in such a way that the entire transparent area is covered by the functional element. Light passing through the transparent area of ​​the laminated glass therefore inevitably also passes through the functional element.

[0021] According to the invention, at least one region of the side edge of the functional element does not extend to the side edge of the composite pane. At least one region of the side edge of the functional element is therefore not flush with the side edge of the composite pane, which in turn is formed by the (essentially flush) side edges of the inner pane, the outer pane, and the intermediate layer. Instead, this region of the side edge of the functional element is set back from the side edge of the composite pane and located in the masking area. The functional element thus has an area that is larger than that of the transparent area but smaller than that of the entire composite pane.

[0022] Typically, the entire circumferential edge of the functional element does not extend to the edge of the laminated glass, but is located within the masking area. Therefore, no portion of the functional element's edge is flush with the edge of the laminated glass. The circumferential edge of the functional element is thus set back from the edge of the laminated glass. In an advantageous embodiment, the distance between the edge of the functional element and the edge of the laminated glass is at least 15 mm to ensure a stable connection between the outer and inner panes at the edge and to prevent moisture from penetrating the functional element.

[0023] Because the side edge of the functional element does not extend to the side edge of the composite disk, direct contact between the functional element and the surrounding atmosphere can be prevented. Instead, the functional element is completely embedded in the composite disk. This is particularly advantageous if the functional element contains metallic components that can corrode upon contact with the atmosphere. In a particularly advantageous embodiment, the functional element therefore contains metal, in particular at least one thin metal-based film.

[0024] Because the side edge of the functional element is positioned within the masking area, it is not visible to the viewer. A visible side edge would be distracting and detract from the aesthetic value of the composite panel.

[0025] According to the invention, the outer surface of the outer pane, facing away from the intermediate layer, has a pattern of coated areas in the masking area, which are provided with a semi-transparent reflective coating. This pattern is present in at least a section of the masking area and can optionally extend beyond the masking area into the transparent area. This makes the pane more aesthetically pleasing to an external observer. This is the major advantage of the invention. The masking area is then less noticeable. This is particularly advantageous for panes that typically do not have a masking strip and would therefore be especially noticeable to the observer (for example, laminated glass in architectural applications or vehicle side windows, especially those that can be raised and lowered).The interior surface of the inner pane, facing away from the intermediate layer, can optionally also be provided with a pattern of coated areas with the semi-transparent reflective coating, making the masking area more aesthetically pleasing for an interior viewer.

[0026] For the purposes of the invention, a semi-transparent reflective coating is understood to be a coating which transmits a significant proportion of the incident electromagnetic radiation in the visible spectral range from 380 nm to 780 nm and reflects an equally significant proportion of said radiation, such that the integrated light transmission and the integrated light reflection each amount to at least 10%, preferably at least 15%, and particularly preferably at least 20%, as measured with a D65 light source when the coating is applied to a clear soda-lime glass sheet with a thickness of 3.85 mm. The light reflection is measured at an angle of incidence and observation of 10°, taking into account both specular and diffuse reflection.Particularly preferably, the integrated light transmission under the aforementioned conditions is from 60% to 90%, in particular from 70% to 80%, and the integrated light reflection is from 10% to 40%, in particular from 20% to 30%.

[0027] The pattern of coated areas means that, in addition to the coated areas, the masking area also contains uncoated areas that are not provided with the semi-transparent reflective coating. The masking area is therefore not completely covered with the semi-transparent reflective coating. The pattern is preferably designed such that the coated areas are not interconnected. Instead, the coated areas are isolated from each other in such a way that each coated area is separated from the others by a continuous uncoated area. The coated areas are thus formed in an island-like manner.The pattern of coated areas is preferably designed such that the surface coverage of the coated areas (i.e. the proportion of coated areas to the total surface of the pattern) is from 5% to 90%, particularly preferably from 10% to 50%, and most preferably from 20% to 40%.

[0028] The coated areas can be designed, for example, in the form of geometric figures or in the form of symbols or logos, such as the company logo of the glass manufacturer or vehicle manufacturer (in the case of a vehicle windshield).

[0029] The extent of each coated area is preferably at least 0.2 mm, particularly preferably at least 0.4 mm, and most preferably from 0.4 mm to 15 mm. The distance between adjacent coated areas is preferably at least 0.5 mm, and the distance of the coated areas from the side edge of the composite panel is preferably at least 1.5 mm.

[0030] The functional element can be designed in various ways. In one embodiment, the functional element reflects electromagnetic radiation passing through the transparent area, particularly infrared (IR) or ultraviolet radiation. This improves thermal comfort in the interior by preventing excessive heating due to solar radiation. The functional element can, for example, be a coating applied to the interior surface of the outer pane or to the exterior surface of the inner pane. A particularly preferred coating is an IR-reflective coating consisting of a stack of thin layers, including at least one layer based on a metal, especially silver. The functional element can also be a coated polymer film, wherein a carrier film is provided with such an IR-reflective coating.The carrier film is typically made of polyethylene terephthalate (PET) and has a thickness of 20 µm to 200 µm. The coated polymer film is preferably arranged between two bonding films of the intermediate layer.

[0031] In a further embodiment, the functional element incorporates a heating function, allowing the laminated glass pane to be electrically heated. Preferably, a thin-film coating of the type described above as an IR-reflective coating is used, deposited either on the outer or inner pane, or on a carrier film. The electrically conductive coating is electrically contacted and connected to an external voltage source, enabling it to be heated by an electric current. The two poles of the voltage source are typically connected to opposite edges of the coating.

[0032] The functional element can also be a colored coating or a colored, coated or printed film to change the color of the transparent area.

[0033] In a further embodiment, the functional element exhibits electrically controllable optical properties. Such a functional element contains an active layer or layer sequence arranged between a first and a second surface electrode. The active layer or layer sequence exhibits variable optical properties that can be controlled by an electrical voltage applied to the surface electrodes. The variable optical properties relate in particular to the degree of light transmission and / or the degree of light scattering, whereby, for the purposes of the invention, "light" is understood to mean, in particular, visible light in the spectral range from 380 nm to 780 nm. For the purposes of the invention, electrically controllable optical properties are understood to mean, in particular, properties that are continuously controllable.However, it is also conceivable that the electrically controllable optical properties can only be switched between two discrete states. Likewise, it is conceivable that the electrically controllable optical properties can be switched between more than two discrete states.

[0034] The electrically controllable functional element can be a PDLC functional element ( polymer dispersed liquid crystalPDLC functional elements contain an active layer between the surface electrodes. The active layer is a PDLC layer and contains liquid crystals embedded in a polymer matrix. PDLC functional elements are typically operated with alternating voltage. If no voltage is applied to the surface electrodes, the liquid crystals are randomly oriented, leading to strong scattering of the light passing through the active layer. If a voltage is applied to the surface electrodes, the liquid crystals align in a common direction, and the transmission of light through the active layer is increased. Such a functional element is known, for example, from DE 102008026339 A1. The term PDLC is to be interpreted broadly within the meaning of the invention and includes related functional elements based on the alignment of liquid crystals, for example, PNLC functional elements ( polymer networked liquid crystal ).

[0035] The electrically controlled functional element can alternatively be an SPD functional element ( suspended particle device SPD functional elements contain an active layer between the surface electrodes. The active layer contains suspended particles, which are preferably embedded in a viscous matrix. SPD functional elements are operated with alternating voltage. The absorption of light by the active layer can be modified by applying a voltage to the surface electrodes, which leads to a change in the orientation of the suspended particles. Such functional elements are known, for example, from EP 0876608 B1 and WO 2011033313 A1.

[0036] The electrically controllable functional element can alternatively be an electroluminescent functional element. In this case, the active layer contains electroluminescent materials, which can be inorganic or organic (OLED). Applying a voltage to the surface electrodes excites the luminescence of the active layer. Such functional elements are known, for example, from US 2004227462 A1 and WO 2010112789 A2.

[0037] In a particularly preferred embodiment, the electrically controllable functional element is an electrochromic functional element. Electrochromic functional elements contain an active layer sequence between the surface electrodes (electrochromic layer sequence). The active layer sequence comprises the following layers arranged one above the other in the specified order: an ion storage layer, an electrolyte layer and an electrochromic layer.

[0038] The electrochromic layer is the actual carrier of the electrically controllable optical properties. It is an electrochemically active layer whose light transmission depends on the degree of ion incorporation. The ions (for example, H+, Li+, Na+, or K+ ions) are stored in the ion storage layer and supplied by it. The electrolyte layer spatially separates the electrochromic layer from the electrochromic layer and facilitates ion migration. When a DC voltage of suitable polarity is applied to the surface electrodes, ions migrate from the ion storage layer through the electrolyte layer into the electrochromic layer, whereupon the optical properties (color, light transmission) of the electrochromic layer change depending on the extent of the incorporated ions.When a direct current voltage of the opposite polarity is applied to the surface electrodes, the ions migrate back from the electrochromic layer through the electrolyte layer into the ion storage layer, and the optical properties of the electrochromic layer change in the opposite way. If no voltage is applied to the surface electrodes, the current state remains stable. Suitable electrochromic layers contain electrochromic materials, for example, inorganic oxides (such as tungsten oxide or vanadium oxide), complex compounds (such as Prussian blue), or conductive polymers (such as 3,4-polyethylenedioxythiophene (PEDOT) or polyaniline). Electrochromic functional elements are known, for example, from WO 2012007334 A1, US 20120026573 A1, WO 2010147494 A1, and EP 1862849 A1.The electrolyte layer is typically formed as a film of organic or inorganic, electrically insulating material with high ionic conductivity, for example, based on lithium phosphorus oxynitride. The ion storage layer is either permanently transparent (pure ion storage) or exhibits electrochromic behavior opposite to that of the electrochromic layer. An example of a pure ion storage layer is one containing a mixed oxide of titanium and cerium; examples of anodically electrochromic ion storage layers are those containing iridium oxide or nickel oxide.

[0039] Electrochromic functional elements are particularly preferred because, compared to other controllable functional elements, they exhibit a slow switching response. This means that, during a switching operation, the user does not perceive a simultaneous and homogeneous change in the optical properties; for example, the viewing area is not simultaneously and homogeneously darkened. Instead, the change in optical properties originates at the point where the surface electrodes are connected to the voltage source and spreads noticeably to the other areas of the functional element. This inhomogeneous, regionally delayed change in optical properties can appear unusual and distracting to the user.The pattern according to the invention, applied to printed areas with the semi-transparent reflective coating, can in this case be used to visually guide the propagation of the change in optical properties. The pattern can indicate a direction that corresponds to the direction of propagation of the change in optical properties, so that the inhomogeneous, delayed switching behavior is perceived as less disruptive, if not even desirable. Suitable and preferred embodiments of the pattern for this purpose will be discussed later.

[0040] The surface electrodes of the functional elements with electrically controllable optical properties are preferably transparent, which, in the context of the invention, means that they have a light transmission in the visible spectral range of at least 50%, preferably at least 70%, and particularly preferably at least 80%. The surface electrodes are, in particular, electrically conductive thin films or thin-film stacks. The surface electrodes preferably contain at least one metal, a metal alloy, or a transparent conductive oxide ( transparent conducting oxide TCO). The surface electrodes preferably contain at least one transparent conductive oxide. The surface electrodes can be based, for example, on silver, gold, copper, nickel, chromium, tungsten, indium tin oxide ( indium tin oxide,The thin film may be formed from a gallium-doped or aluminum-doped zinc oxide and / or fluorine-doped or antimony-doped tin oxide, preferably based on silver or ITO, particularly ITO. The surface electrodes preferably have a thickness of 10 nm to 2 µm, particularly preferably 20 nm to 1 µm, most preferably 30 nm to 500 nm, and particularly 50 nm to 200 nm. If a thin film is formed based on a material, this means, within the meaning of the invention, that the layer consists largely of the material (more than 50 wt.%, preferably more than 90 wt.%, particularly more than 99 wt.%), whereby the layer may contain other materials to a small extent, for example, dopants.

[0041] The functional element with electrically controllable optical properties can be formed directly on the inner surface of the outer pane or on the outer surface of the inner pane. In a preferred embodiment, however, the functional element is designed as a multilayer film. The multilayer film is a stack of layers, wherein the layers of the stack comprise at least a first carrier film, the first surface electrode, the active layer or active layer sequence, the second surface electrode, and a second carrier film, which are arranged one above the other in this order. The layers of the stack are permanently and stably bonded to one another, for example by adhesive bonding or lamination.Multilayer films of this type are typically commercially available and can, for example, be purchased by a glass manufacturer, cut to the required size and inserted into the laminated glass pane.

[0042] The carrier films preferably contain at least one thermoplastic polymer or are based on one, most preferably polyethylene terephthalate (PET), polypropylene, polyvinyl chloride, fluorinated ethylene propylenes, polyvinyl fluoride, or ethylene tetrafluoroethylene, and most preferably PET. This is particularly advantageous with regard to the stability of the multilayer film. The thickness of each carrier film is preferably from 0.05 mm to 1 mm, more preferably from 0.1 mm to 0.5 mm, and particularly from 0.1 mm to 0.2 mm. Carrier films with such a small thickness advantageously result in a small thickness of the glazing in which the multilayer film is to be used. Furthermore, effective protection of the active layer and the electrically conductive layers is ensured.In the inventive method, the carrier films are preferably not damaged, i.e., the insulation line does not extend to the carrier films.

[0043] The side edge of the multilayer film can be sealed, for example by fusing the carrier films or by a (preferably polymeric) band. This protects the active layer, in particular from components (especially plasticizers) of the interlayer of a laminated glass unit, in which the multilayer film is embedded, diffusing into the active layer, which can lead to degradation of the functional element.

[0044] The multilayer film is preferably embedded in the intermediate layer of the laminated glass. For this purpose, each carrier film is preferably connected to one of the glass panes via at least one thermoplastic bonding film. The bonding is carried out under the influence of heat, vacuum, and / or pressure according to methods known per se. The two aforementioned bonding films on both sides of the multilayer film preferably extend beyond the multilayer film all around. Particularly preferably, the side edges of the multilayer film are surrounded all around by a frame-like third thermoplastic bonding film. This third film has a recess into which the multilayer film is inserted.

[0045] The surface electrodes of the functional element with electrically controllable optical properties are preferably connected by means of so-called busbars (combining conductors, busbars) electrically contacted. These are preferably designed as strips of an electrically conductive foil, for example, a copper foil. The width of the busbars is preferably from 1 mm to 10 mm, for example, about 5 mm. The thickness of the busbars is preferably from 50 µm to 200 µm, for example, about 90 µm.

[0046] These busbars are preferably arranged in the edge region of the functional element in direct contact with the surface electrodes. The busbars are particularly well positioned within the masking area of ​​the composite disc, so that they are not visible. The busbars are in turn connected to the voltage source via electrical cables.

[0047] The functional element typically has a substantially polygonal shape, determined by the shape of the composite disk, for example, essentially the shape of a rectangle, a triangle, or a trapezoid. The shape may exhibit slight deviations from the strictly geometric polygon; for example, the sides may be slightly curved instead of straight. However, the circumferential edge of the functional element has several sections that are straight or slightly curved (i.e., that have a constant or continuously changing direction of extension), with adjacent sections separated by vertices where the direction of extension changes abruptly.

[0048] The surface electrodes are preferably electrically contacted by a current busbar in at least one section of the circumferential edge region of the functional element. Particularly preferably, the current busbar of the first surface electrode and the current busbar of the second surface electrode are arranged in the same section of the circumferential edge region and, in particular, substantially flush. Most preferably, the current busbars are arranged along a large proportion of at least one of the sides of the polygonal shape (for example, along at least 80% or at least 90% of said side).

[0049] In this case, at least the section of the masking area in which the busbars are arranged is provided with a pattern of coated areas with the semi-transparent reflective coating. In said section, the pattern preferably extends over at least 80% of the width of the masking area, more preferably at least 90%, and more preferably substantially the entire width. If the functional element (and also the composite panel) is substantially polygonal and the busbars are arranged on one of the sides of the polygon, particularly along a large part of this side, then, at least in the usual case where the functional element is completely embedded within the interlayer and does not extend anywhere to the side edge of the composite panel, a frame-like masking area will be present to conceal the circumferential side edge of the functional element.This frame-like masking area, corresponding to the shape of the laminated panel, will also essentially have a polygonal form. The pattern of coated areas is then present at least in the area where the busbars are located; in particular, the entire side of the polygonal masking area is provided with the pattern where the busbars are located. This is particularly advantageous for functional elements with comparatively slow switching behavior, especially electrochromic functional elements, because the change in optical properties propagates from the busbars across the transparent area of ​​the laminated panel. The pattern of printed areas associated with the busbars can indicate the direction of propagation, so that the inhomogeneous switching behavior appears less bothersome or even desirable to the user.

[0050] In a particularly preferred embodiment, the current busbars (complete or interrupted) are mounted circumferentially on the surface electrodes. Thus, the current busbars are not only mounted on one side of the functional element, but along the entire circumferential edge region. This is particularly advantageous for functional elements with comparatively slow switching behavior, especially electrochromic functional elements, because the circumferential electrical contact leads to a faster change in the optical properties after a switching operation. The change in optical properties then originates at the circumferential edge of the viewing area and propagates towards the center of the viewing area, a phenomenon also known as the "iris effect."The busbars can be formed from a single circumferential strip of electrically conductive film (complete circumferential, with a possible gap between the ends of the circumferential strip). Alternatively, the busbars can also have gaps (interrupted circumferential). They can be composed of several strips of electrically conductive film, and gaps may be present between the strips, particularly at the corners of the polygonal functional element. However, at least 80% of the circumferential edge region of the surface electrodes should be provided with the busbars, preferably at least 90%, and particularly at least 95%. The masking area surrounds the transparent area like a frame and covers the circumferential side edge of the functional element and the circumferential busbars. In this case, the masking area is completely covered with the pattern of coated areas.The pattern of printed areas, which is assigned to the surrounding busbars, can indicate the direction of propagation towards the center of the viewing area, so that the iris effect appears less disturbing or even desirable to the user.

[0051] If the circumferential busbars are composed of several strips of an electrically conductive film, the individual strips can optionally be electrically contacted independently of one another. This allows for the implementation of independent switching sections within the visible area. The individual strips are connected, for example, via thin wires to a control unit, such as a flexible printed circuit board laminated into the composite disc. The wires preferably have a diameter of 90 µm to 110 µm. For practical and electrical reasons, the wires should be spaced at least 5 mm apart and at least 6 mm from the side edge of the composite disc. The wires should also run entirely within the masking area.

[0052] The semi-transparent reflective coating preferably contains a metal oxide. The metal is particularly preferably selected from the group consisting of aluminum, tin, titanium, copper, chromium, cobalt, iron, manganese, zirconium, cerium, yttrium, silver, gold, platinum, and palladium. The coating can also contain mixtures of the aforementioned oxides or mixed oxides of the aforementioned metals. Optically appealing semi-transparent reflective properties can be achieved with such metal oxides. The metal oxide content in the reflective coating is preferably at least 70%, particularly preferably at least 80%, and most preferably at least 90%.

[0053] The thickness of the semi-transparent reflective coating is preferably from 5 µm to 50 µm, particularly preferably from 8 µm to 16 µm. This yields particularly good results.

[0054] The semi-transparent reflective coating is preferably applied to the coated areas using a printing process, i.e., printed on. The coating is applied to the coated areas as a printing paste and then dried or baked on.

[0055] The screen printing process is particularly preferred. In this process, the printing paste is pressed through a fine mesh screen. The ink is forced through the screen, for example, using a squeegee. A stencil, typically made of metal or plastic, is applied to the screen. This stencil has areas that are permeable to the printing paste and areas that are impermeable, thus defining the geometric shape of the print—in this case, the pattern of printed areas. Alternatively, the screen itself can be designed with permeable and impermeable areas, thereby acting as the stencil.

[0056] Alternatively, other printing methods can be used, such as pad printing or stamp printing. The coating can also be applied manually instead of printed, for example with a brush.

[0057] The printing paste typically contains a solvent in addition to the reflective material (especially a metal oxide). Alcohols, glycols (for example, polypropylene glycols), or derivatives thereof are preferred as solvents. The printing paste also preferably contains a thickening agent, for example, a cellulose derivative or polyacrylic acid.

[0058] Such pastes for producing reflective coatings are commercially available, for example from Ferro GmbH. Furthermore, such coatings are known from patent literature, for example from WO2005063645.

[0059] The application of the semi-transparent reflective coating to the outer pane can take place before or after the manufacturing of the laminated pane. After the printing paste has been applied, the outer pane (or the laminated pane) undergoes a heat treatment, during which the solvent is driven off by evaporation and the coating is fixed to the surface of the outer pane. The heat treatment can also be carried out in several steps, for example, a drying step at 50°C to 180°C and a curing step (calcification) at 200°C to 1000°C, particularly at 400°C to 700°C.

[0060] The semi-transparent reflective coating is particularly preferably a sol-gel coating, meaning it is produced on the coated areas using the sol-gel process. This allows for mechanically and chemically stable coatings with good semi-transparent properties. First, a sol containing the coating precursors is prepared and matured. The maturation process can involve hydrolysis of the precursors and / or a (partial) reaction between the precursors (in particular, partial aggregation by polycondensation). For the purposes of the invention, this sol is referred to as the precursor sol and preferably contains metal oxide precursors in a solvent. The metal oxide precursors can be, for example, organometallic compounds, metal alkoxides, or metal carboxylates.In a preferred embodiment, the metal (for example, the metal alcoholate or carboxylate) is stabilized by ligands in the form of a chemical complex, which reduces the reactivity and improves the sol's resistance to atmospheric moisture. 2,4-Diketones are commonly used as ligands.

[0061] The solvent of the sol is preferably an alcohol, ether, or glycol. Alcohols such as ethanol, n-propanol, isopranol, or butanol are particularly preferred. Glycols such as di-, tri-, tetra-, penta-, or hexamers of ethylene glycol, polypropylene glycols (for example, dipropylene glycol, tripropylene glycol, or tetrapropylene glycol), and derivatives thereof are also particularly preferred. Ethers such as dimethyl ether or diethyl ether are also particularly preferred. Mixtures of the solvents mentioned may also be used.

[0062] In addition to the precursors and the solvent, the sol preferably contains thickening agents, particularly preferably cellulose derivatives (such as methylcellulose or ethylcellulose) or polyacrylic acids. The viscosity of the sol can be adjusted by means of the thickening agents, especially with regard to the printing process for applying the sol (as a printing paste) to the disk surface.

[0063] It is possible that the solvent or thickener also acts as a complexing agent for the metal oxide precursors if they are appropriately chosen. In this case, there is no need to add additional ligands.

[0064] The sol may also contain typical additives, such as those commonly used in sol-gel technology and known to experts.

[0065] The sol is deposited on the outer surface of the outer disc, preferably printed on as a printing paste. This is followed by drying, during which the solvent evaporates. This drying can be carried out at ambient temperature or by separate heating (for example, at a temperature up to 120 °C). Before applying the solution, the surface is typically cleaned using methods known per se.

[0066] The sol is then condensed, resulting in the coating according to the invention. The condensation may include a heat treatment, for example at a temperature of 500 °C to 700 °C. Typically, crosslinking processes take place among the precursors, whereby the precursors first combine to form aggregates (aggregation, typically through hydrolysis of the precursors and polycondensation reactions among them) and these are subsequently crosslinked to form a gel (gelation). The aggregation can also partially occur in solution before the coating is applied to the disk surface.

[0067] In a particularly advantageous embodiment, the semi-transparent reflective coating is color-matched to the functional element, so that the coating and the functional element exhibit a similar, ideally essentially the same, hue when darkened. This leads to particularly aesthetically pleasing results. This is especially advantageous for electrochromic functional elements, which are characterized by a significant coloration (compared, for example, to SPD or PDLC functional elements).

[0068] In an advantageous embodiment, the coverage density of the pattern decreases from coated areas towards the viewing area. This means that the uncoated area of ​​the pattern increases towards the viewing area, while the coated area decreases. This can be achieved by decreasing the number of coated areas per unit area towards the viewing area and / or by decreasing the size of the coated areas towards the viewing area. The coverage therefore depends on the distance to the viewing area, with the coverage increasing with increasing distance. This is particularly advantageous for functional elements with comparatively slow switching behavior, especially electrochromic functional elements.With such functional elements, the change in the optical properties of the viewing area is not perceived by the user as simultaneous and homogeneous, but rather spreads noticeably from the edge of the viewing area (which is located a short distance from the busbar) towards the center of the pane. This direction of the time-delayed change in the optical properties is visually indicated by the inhomogeneous pattern of coated areas, the coverage of which decreases towards the viewing area, thus making the delay seem less disruptive to the user, if not even as a deliberate design feature. Depending on the application, it is also possible for the coverage density of the pattern of coated areas to increase towards the viewing area.

[0069] In a further advantageous embodiment, the pattern of coated areas is formed from lines or stripes directed towards the viewing area. In other words, the coated areas are formed as lines or stripes, and their direction of extension points towards the viewing area. This embodiment is also advantageous for functional elements with comparatively slow switching behavior, particularly electrochromic functional elements. The direction of the time-delayed change in the optical properties is visually indicated by the orientation of the lines or stripes, making the delay appear less disruptive to the user, if not even as a deliberate design feature.

[0070] Ideally, the functional element should be protected from ultraviolet (UV) and infrared (IR) components of solar radiation, which can lead to its degradation. Protection against UV radiation is preferably achieved by a thermoplastic layer containing a UV blocker between the functional element and the outer pane. Protection against IR radiation is preferably achieved by an IR-reflective coating. The IR-reflective coating can be applied directly to the outer pane, particularly to its inner surface. If both a printed cover and an IR-reflective coating are applied to the inner surface of the inner pane, the printed cover can optionally have corrosive properties towards the IR-reflective coating, causing the latter to be automatically removed in the areas covered by the printed cover.The IR-reflective coating can be positioned above or below the printed cover (relative to the outer pane). Typical IR-reflective coatings are thin-film stacks with at least one silver-based layer.

[0071] The IR-reflective coating can also be provided on a carrier film and embedded in the intermediate layer between the functional element and the outer pane. For this purpose, the coated carrier film is preferably positioned between two bonding films. Carrier films are typically PET-based and have a thickness of 20 µm to 200 µm.

[0072] The composite pane according to the invention can be manufactured by methods known per se. The outer pane and the inner pane are arranged with the layers of the intermediate layer and the functional element located between them to form a layer stack and laminated together, for example by autoclave processes, vacuum bag processes, vacuum ring processes, calender processes, vacuum laminators, or combinations thereof. The bonding of the outer pane and the inner pane via the intermediate layer is usually carried out under the influence of heat, vacuum, and / or pressure. The application of the semi-transparent reflective coating to the outer surface of the outer pane can take place before or after the lamination of the composite pane. As already described, the semi-transparent reflective coating is preferably applied by printing processes and formed by a sol-gel process.

[0073] The laminated glass can be flat or curved in one or both spatial directions, as is particularly common for vehicle windows in passenger cars. Typically, the outer and inner panes are curved before being laminated together to form the laminated glass. The application of the semi-transparent reflective coating is preferably carried out before the panes are curved, as the coating is easier to apply to flat panes.

[0074] The invention further comprises the use of a laminated glass pane according to the invention as a vehicle window, particularly preferably as a vehicle side window, especially a side window that can be opened, lifted, and lowered. Since the masking area is unusual in such windows, the partially transparent reflective coating according to the invention, which makes it less visually noticeable, is particularly advantageous here. The laminated glass pane can also be used as another type of vehicle window, for example, as a windshield, roof window, or rear window. It is also possible to use the laminated glass pane in the architectural field, for example, as a window pane in a building or a room inside a building, or as a glass facade.

[0075] The invention is explained in more detail with reference to a drawing and exemplary embodiments. The drawing is a schematic representation and not to scale. The drawing does not limit the invention in any way. It shows: Fig. 1 a top view of an embodiment of a composite disk according to the invention, Fig. 2 a cross-section along XX' through the composite disk according to Figure 1 , Fig. 3 a top view of the functional element of the composite disc according to Figure 1 , Fig. 4 a cross-section along YY' through the functional element made of Figure 3 Fig. 5 a top view of a further embodiment of the functional element, Fig. 6 a top view of a further embodiment of the functional element, Fig. 7 a top view of a composite disc with the functional element according to Figure 6 , Fig. 8 an enlarged view of section Z from Figure 1In one embodiment of the invention, Fig. 9 shows an enlarged view of the section Z; in a further embodiment, Fig. 10 shows an enlarged view of the section Z; and Fig. 11 shows an enlarged view of the section Z in a further embodiment.

[0076] Figure 1 and Figure 2Figures 1 and 2 each show a detail of a laminated glass pane according to the invention. The laminated glass pane is exemplified as an opening, i.e., liftable and lowerable, side window of a passenger car. The laminated glass pane comprises an outer pane 1 and an inner pane 2, which are bonded together via an intermediate layer 3. The outer pane 1 and the inner pane 2 are made of clear soda-lime glass with a thickness of 2.1 mm. In its installed position, the outer pane 1 faces the external environment, and the inner pane 2 faces the vehicle interior. The outer pane 1 has an external surface I and an internal surface II. Similarly, the inner pane 2 has an external surface III and an internal surface IV. In its installed position, the external surfaces I and III face the external environment, and the internal surfaces II and IV face the vehicle interior.

[0077] The laminated glass pane has a central transparent viewing area D and an opaque masking area M surrounding it like a frame. The opaque masking area M is created by a printed coating 10 on the interior surfaces II and IV of the outer pane 1 and the inner pane 2. The printed coating 10 is made of a black enamel containing a black pigment and glass frits, which is fired into surfaces II and IV. The masking area M surrounds the visible area of ​​the side window when closed within a circumferential border. Below the marked area M and the viewing area D, the laminated glass pane has a mounting area B, which is always located within the vehicle body and serves to connect the laminated glass pane to the mechanism for raising and lowering it. The mounting area B may include holes and / or mounting elements (not shown).

[0078] The intermediate layer 3 comprises a total of three thermoplastic layers 3a, 3b, and 3c, each formed by a thermoplastic PVB film. The first thermoplastic layer 3a is bonded to the outer pane 1, has a thickness of, for example, 0.76 mm, and contains UV blockers. The second thermoplastic layer 3b is bonded to the inner pane 2 and has a thickness of, for example, 0.38 mm. The third thermoplastic layer 3c, located between the two, has a thickness of, for example, 0.38 mm and is formed with a cutout into which a functional element 4 with electrically controllable optical properties is inserted with a precise fit, i.e., approximately flush on all sides.The third thermoplastic layer 3c thus forms a kind of passe-partout or frame for the approximately 0.4 mm thick functional element 4, which does not extend to the side edges of the laminated glass, but is encapsulated and thereby protected all around in thermoplastic material. The functional element 4 is an electrochromic multilayer film that can be switched from a transparent, uncolored state to a colored state with reduced light transmission.

[0079] Functional element 4 completely covers the viewing area D and extends into the masking area M, where its side edges are positioned so that they are not visible. The light transmission of the viewing area D can be electrically controlled by the user via functional element 4.

[0080] The functional element 4 is protected from UV radiation by the UV-blocking first thermoplastic layer 3a. To protect the functional element 4 from the infrared components of sunlight, a solar control coating 13 is applied to the interior surface II of the outer pane 1. The solar control coating 13 is, for example, a sputtered thin-film stack with one or more silver layers. A circumferential edge region of the outer pane 1 is not covered with the solar control coating 13, so that it has no contact with the atmosphere and is protected from corrosion. The side edges of the solar control coating 13 are also located in the masking area M.

[0081] Variations of the illustrated design are conceivable. For example, the masking area M can be realized not only by the cover print 10 but also by an opaquely colored area of ​​at least one of the thermoplastic layers 3a, 3b, 3c. The IR protection can be achieved not only by the solar control coating 13 on the outer pane 1 but also by an IR-reflective film. Such films consist, for example, of a PET carrier film with an IR-reflective coating. Typically, the IR-reflective film is inserted between two layers of the intermediate layer 3, in particular between the first thermoplastic layer 3a and another thermoplastic layer, which is arranged between the first thermoplastic layer 3a and the outer pane 1. The additional thermoplastic layer can, for example, be a PVB film with a thickness of 0.38 mm.

[0082] In the masking area M, the outer surface I of the outer pane 1 is provided with a pattern of coated areas b, which have a semi-transparent reflective coating 11. The coating 11 is a sol-gel coating applied to the surface I by screen printing. It contains metal oxide, for example titanium oxide, and has a thickness preferably of 50 nm to 200 nm, for example 70 nm. The pattern with the coated areas b serves to make the masking area more aesthetically pleasing. Since masking areas are uncommon for side windows, the masking area M is perceived as less intrusive by the observer due to the coated areas b.

[0083] Figure 3 and Figure 4 each show a detail of functional element 4 from Figure 1The functional element 4 is an electrochromic multilayer film. The multilayer film is bounded by a first carrier film 8 and a second carrier film 9. The carrier films 8 and 9 are made of PET and have a thickness of, for example, 0.125 mm. The carrier films 8 and 9 are each coated with an ITO layer approximately 100 nm thick, forming a first surface electrode 6 and a second surface electrode 7. An active layer sequence 5 is arranged between the surface electrodes 6 and 7. The layer sequence 5 is an electrochromic layer sequence and consists of an ion storage layer 5a, an electrolyte layer 5b, and an electrochromic layer 5c. By applying a DC voltage to the surface electrodes 6 and 7, ions can be stimulated to migrate from the ion storage layer 5a through the electrolyte layer 5b into the electrochromic layer 5c and vice versa.The proportion of ions in the electrochromic layer 5c determines its optical properties, in particular the light transmittance and the color.

[0084] Both surface electrodes 6, 7 are electrically contacted around their circumference by a current busbar 12. The current busbars 12 serve to connect the surface electrodes 6, 7 to an external voltage source in order to provide the electrical voltage required to control the optical properties. The current busbars 12 are arranged in the masking area M. Each current busbar 12 is formed from a single strip of copper foil, which completely surrounds the respective surface electrode 6, 7, with a gap only between the ends of the strip.

[0085] Circumferential busbars 12 are advantageous for electrochromic functional elements 4 because these exhibit a comparatively slow switching behavior. The circumferential electrical contacting results in a faster change in the optical properties of the transparent area D. Nevertheless, the observer does not perceive the change in optical properties as homogeneous; instead, it originates at the edge of the transparent area D and propagates noticeably towards the center. This observation is also referred to as the "iris effect." The pattern of printed areas b according to the invention can be used to indicate the direction of the delayed change in optical properties and to present this iris effect as deliberately created, thus increasing the aesthetic value of the laminated panel. Possible embodiments of the pattern are described in the Figures 8 to 11 Shown as an example.

[0086] Figure 5Figure 4 shows a further embodiment of the functional element 4 with circumferential busbars 12. The busbars 12 are each composed of several strips of copper foil, whereby gaps can form between adjacent strips. This embodiment can be compared to that of the Figure 3 for manufacturing reasons it may be preferred. In addition, it opens up the possibility of independently electrically controlling the individual strips of the power busbars 12, so that independent switching areas are realized whose optical properties can be controlled independently of each other.

[0087] Figure 6 and Figure 7 Each shows a detail of a further embodiment of the composite disc according to the invention, which is also an opening side window of a passenger car. Figure 6 shows a top view of the functional element 4 with the busbars 12, Figure 7 a top view of the composite disc equipped with it.

[0088] The design is basically structured in the same way as that of the Figures 1 to 4The difference lies in the fact that the busbars 12 are not arranged circumferentially, but only along the lower edge of the functional element 4. The change in the optical properties of the electrochromic functional element 4 therefore originates at the lower edge and propagates towards the upper edge. Analogous to the "iris effect," this could be described as a "sunrise effect." To indicate the direction of the delayed change in optical properties, in this case only the section of the masking area M with the pattern of printed areas b, in which the busbars are arranged, adjacent to the lower edge of the transparent area D (origin of the change in optical properties), is provided. Alternatively, it is also possible to additionally provide the opposite section of the masking area M, adjacent to the upper edge of the transparent area D, with the pattern (endpoint of the change in optical properties).Alternatively, it is also possible in this configuration to apply the pattern all around the entire masking area M.

[0089] Figure 8 shows section Z from Figure 1 In one embodiment of the inventive pattern of coated areas b, the pattern is enlarged. The pattern is homogeneous, meaning that the coated areas b are uniformly distributed and identically formed. The individual coated areas b are shown by way of example as triangles, but can also have any other shape. The triangle symbolizes a shape with a preferred direction (upward-pointing apex of the triangle) which is directed towards the transparent area. This allows the direction of the change in optical properties to be indicated despite the homogeneity of the pattern.

[0090] Figure 9 shows section Z from Figure 1In a further embodiment of the inventive pattern of coated areas b, the pattern is enlarged. The pattern is not homogeneous. Instead, the coverage of the coating 11 decreases towards the transparent area D. This indicates the direction of the change in optical properties. The individual printed areas b are identical in shape and size. The change in coverage is achieved by a decrease in the number of printed areas b per unit area towards the transparent area D. The individual coated areas b are shown as circles by way of example, but can also have any other shape, for example, the company logo of the vehicle manufacturer.

[0091] Figure 10 shows section Z from Figure 1In a further embodiment of the inventive pattern of coated areas b, the pattern is enlarged. Here too, the pattern is not homogeneous. Instead, the coverage of the coating 11 decreases towards the transparent area D. This indicates the direction of the change in optical properties. The change in coverage is achieved by the size of the individual printed areas decreasing towards the transparent area D. The individual coated areas b are shown as circles by way of example, but can also have any other shape, for example, the company logo of the vehicle manufacturer.

[0092] Figure 11 shows section Z from Figure 1In a further embodiment of the inventive pattern, the coated areas b are enlarged. The individual coated areas b are formed as thin, line-like strips directed towards the transmission area D. This allows the direction of the change in optical properties to be indicated. List of reference symbols:

[0093] (1) Outer pane (2) Inner pane (3) Thermoplastic interlayer (3a) First layer of interlayer 3 (3b) Second layer of interlayer 3 (3c) Third layer of interlayer 3 (4) Functional element (5) Active layer sequence of functional element 4 (5a) Ion storage layer of an electrochromic layer sequence 5 (5b) Electrolyte layer of an electrochromic layer sequence 5 (5c) Electrochromic layer of an electrochromic layer sequence 5 (6) First surface electrode of functional element 4 (7) Second surface electrode of functional element 4 (8) First carrier film of functional element 4 (9) Second carrier film of functional element 4 (10) Cover print (11) Semi-transparent reflective coating (12) Busbar (13) Sun protection coating (I) Outer surface of outer pane 1 (II) Inner surface of outer pane 1 (III) Outer surface of inner pane 2 (IV) Inner surface of inner pane 2 (M)opaque masking area of ​​the laminated pane (D)transparent viewing area of ​​the laminated pane (B)mounting area of ​​the laminated pane (b)coated area of ​​the outer surface I of the outer pane 1 X - X's intersection line Y - Y's intersection line Z - Enlarged area

Claims

1. Composite pane, comprising an outer pane (1) and an inner pane (2), which are interconnected via a thermoplastic intermediate layer (3), wherein the composite pane has an opaque masking region (M) and a transparent see-through region (D), wherein the intermediate layer (3) has a functional element (4) which covers the entire see-through region (D), wherein at least one region of the side edge of the functional element (4) does not extend as far as the side edge of the composite pane but is arranged within the masking region (M), and wherein the surface (I) of the outer pane (1) facing away from the intermediate layer (3) has a pattern of coated regions (b) in the masking region (M) which are provided with a partially transparent reflective coating (11), wherein the partially transparent reflective coating (11) transmits a significant portion of the electromagnetic radiation incident thereon in the visible spectral range from 380 nm to 780 nm and reflects a likewise significant portion of said radiation, so that the integrated light transmission and the integrated light reflection are each at least 10%, measured as specified in the description.

2. Composite pane according to claim 1, wherein the masking region (M) surrounds the see-through region (D) in a frame-like manner.

3. Composite pane according to either claim 1 or claim 2, wherein the masking region (M) is formed by a cover print (10) on the surface (II) of the outer pane (1) facing the intermediate layer (3) or by a tinted or colored film in the intermediate layer (3).

4. Composite pane according to claim 3, wherein the functional element (4) is an electrochromic functional element comprising an electrochromic active layer sequence (5) between two planar electrodes (6, 7).

5. Composite pane according to claim 4, wherein the planar electrodes (6, 7) are electrically contacted in at least one portion of the edge region of the functional element (4) in each case by a busbar (12), wherein the busbars (12) are arranged within the masking region (M) and wherein at least the portion of the masking region (M) in which the busbars (12) are arranged is provided with the pattern of coated regions (b).

6. Composite pane according to either claim 4 or claim 5, wherein - the busbars (12) are mounted on the periphery of the planar electrodes (6, 7), - the masking region (M) surrounds the see-through region (D) in a frame-like manner, and - the masking region (M) is peripherally provided with the pattern of coated regions (b).

7. Composite pane according to any of claims 1 to 6, wherein the partially transparent reflective coating (11) is printed onto the coated regions (b), preferably by a screen printing method.

8. Composite pane according to any of claims 1 to 7, wherein the partially transparent reflective coating (11) is a sol-gel coating.

9. Composite pane according to any of claims 1 to 8, wherein the partially transparent reflective coating (11) contains metal oxide.

10. Composite pane according to claim 9, wherein the metal is selected from the group consisting of aluminium, tin, titanium, copper, chromium, cobalt, iron, manganese, zirconium, cerium, yttrium, silver, gold, platinum and palladium.

11. Composite pane according to any of claims 1 to 10, wherein the thickness of the partially transparent reflective coating (11) is from 5 µm to 50 µm, preferably from 8 µm to 16 µm.

12. Composite pane according to any of claims 1 to 11, wherein the coverage density of the pattern of coated regions (b) decreases towards the see-through region (D).

13. Composite pane according to any of claims 1 to 11, wherein the pattern of coated regions (b) is formed from lines or strips directed toward the see-through region (D).

14. Use of a composite pane according to any of claims 1 to 13 as a vehicle pane, in particular as a vehicle side pane.