Composite pane having electrically controllable optical properties

Abstract

The present invention relates to a composite pane having electrically controllable optical properties, the composite pane comprising an electrically controllable functional element (10) which has, in the order indicated, a first carrier film (12), a first surface electrode (14), an active layer (11) or layer sequence having electrically controllable optical properties, a second surface electrode (15), and a second carrier film (13). In a first contacting region, the second carrier film (13), the second surface electrode (15), and the active layer (11) or layer sequence are removed, and the first surface electrode (14) is electrically conductively connected to a busbar (21). In a second contacting region, the first carrier film (12), the first surface electrode (14), and the active layer (11) or layer sequence are removed, and the second surface electrode (15) is electrically conductively connected to at least one busbar (21; 22.1, 22.2, 22.3). According to the invention, the first contacting region and the second contacting region are arranged on opposite sides of the functional element (10), and the current busbar (21) of the first surface electrode (14) extends in a connecting region from the first contacting region to the opposite side of the functional element (10), wherein the second carrier film (13), the second surface electrode (15), and the active layer (11) or layer sequence are removed in the connecting region. Between the second contacting region and the connecting region, there is an intermediate region in which the first carrier film (12), the first surface electrode (14), and the active layer (11) or layer sequence are not removed, and in which a part of the second surface electrode (15) which is adjacent to the connecting region is electrically insulated from the remainder of the second surface electrode (15) by an insulating line (16).

Description

[0001] Composite pane with electrically controllable optical properties

[0002] The invention relates to a composite pane with electrically controllable optical properties and its use.

[0003] Composite panes with electrically controllable optical properties are known as such. They are equipped with functional elements comprising an active layer or layer sequence between two surface electrodes, wherein the optical properties of the active layer or layer sequence can be changed by an electrical voltage applied to the surface electrodes. One example of such functional elements are SPD functional elements (suspended particle device), which are known, for example, from EP 0876608 B1 and WO 2011033313 A1. The applied voltage can be used to control the transmission of visible light through SPD functional elements. Another example is PDLC functional elements (polymer dispersed liquid crystal), which are known, for example, from DE 102008026339 A1. The active layer contains liquid crystals embedded in a polymer matrix.If no voltage is applied, the liquid crystals are randomly aligned, which leads 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. The PDLC functional element works less by reducing the overall transmittance than by increasing the scattering, which can prevent clear visibility or provide glare protection. Electrochromic functional elements are also known, for example from US 20120026573 A1, WO 2010147494 A1, EP 1862849 A1, and WO 2012007334 A1, in which a change in transmission occurs through electrochemical processes induced by the applied electrical voltage.

[0004] Such composite panes can be used, for example, as vehicle windows, whose light transmission behavior can then be electrically controlled. They can be used, for example, as roof windows to reduce solar radiation or mitigate annoying reflections. Such roof windows are known, for example, from DE 10043141 A1 and EP 3456913 A1. Windshields have also been proposed in which an electrically controllable sun visor is implemented using a switchable functional element to replace the conventional mechanically foldable sun visor in motor vehicles. Windshields with electrically controllable sun visors are known, for example, from DE 102013001334 A1, DE 102005049081 B3, DE 102005007427 A1 and DE 102007027296 A1. However, such composite panes can be used not only in the vehicle sector, but also, for example, in building glazing or interior window panes.

[0005] The electrically controllable functional elements are typically provided as a multilayer film and embedded in the intermediate layer of the composite pane. The multilayer film is constructed from two carrier films, typically based on PET, with the surface electrodes deposited thereon, typically based on ITO, and the active layer or layer sequence located between them. For electrical contact, a contacting area is typically created for each surface electrode by removing the opposite carrier film with the other surface electrode and the active layer or layer sequence, so that said surface electrode is exposed in the contacting area and can be electrically contacted via a current collecting bar, typically a strip of copper foil.Electrical conductors are connected to the busbars, which extend beyond the side edge of the composite pane to connect the functional element to the external voltage source.

[0006] The contact areas of the two surface electrodes are typically formed on opposite sides of the functional element, which is advantageous for the optical behavior of the functional element, in particular because it ensures more uniform and sometimes faster switching behavior. However, this fact brings with it disadvantages with regard to manufacturing. Since the process steps for electrical contacting are carried out on opposite sides of the functional element, the manufacturing effort is increased. In particular, comparatively long electrical conductors are required, which are applied, for example, as metal wires using a plotter to thermoplastic films of the intermediate layer of the composite pane, which is time-consuming.

[0007] DE202018102520U1 discloses a composite pane with an electrically controllable functional element, the contacting areas of which are arranged on opposite sides of the functional element. The busbars are L-shaped, so that the busbar of the first surface electrode extends from a first contacting area to the opposite side of the functional element in a connecting area. This allows the electrical conductors on the same side of the functional element to be connected to the two busbars.Since the second carrier foil, the second surface electrode and the active layer or layer sequence must be removed in the connection region in order to arrange the current collecting bar on the first surface electrode, and the second surface electrode then directly adjoins the connection region in which the first surface electrode is exposed, there is a risk that the second surface electrode comes into contact with the first surface electrode, the current collecting bar of the first surface electrode or their electrical contacts and causes a short circuit.

[0008] The present invention is based on the object of providing an improved composite pane with electrically controllable optical properties, which is in particular easier to manufacture and in which short circuits are avoided.

[0009] The object is achieved according to the invention by a composite pane with electrically controllable optical properties according to independent claim 1. Advantageous embodiments emerge from the subclaims.

[0010] The invention is based on the approach of extending one of the busbars and routing it in a connection area to the opposite side of the functional element, where the other busbar is also located. The electrical connection of both busbars can then be made on the same side of the functional element, reducing manufacturing costs. Fewer electrical conductors are also required, allowing for faster design, for example, using a plotter. These are major advantages of the present invention.

[0011] The composite pane according to the invention with electrically controllable optical properties comprises an outer pane and an inner pane, which are connected to one another via a thermoplastic intermediate layer. The composite pane further comprises an electrically controllable functional element embedded in the intermediate layer. The functional element has, in the specified order, a first carrier film, a first surface electrode, an active layer or layer sequence with electrically controllable optical properties, a second surface electrode, and a second carrier film. The carrier films, the surface electrodes, and the active layer / layer sequence are typically arranged substantially parallel to the surfaces of the outer pane and the inner pane.

[0012] The functional element has a first contacting region, which is provided for the electrical connection of the first surface electrode. In the first contacting region, the second carrier film, the second surface electrode, and the active layer or layer sequence are removed. In the first contacting region, the first carrier film and the first surface electrode remain, so that the first surface electrode is exposed and can be electrically contacted. In the first contacting region, the first surface electrode is electrically connected to a current collecting bar. For this purpose, the current collecting bar is arranged on the first surface electrode in the first contacting region.

[0013] The functional element also has a second contacting region, which is provided for the electrical connection of the second surface electrode. In the second contacting region, the first carrier film, the first surface electrode, and the active layer or layer sequence are removed. In the second contacting region, the second carrier film and the second surface electrode remain, so that the second surface electrode is exposed and can be electrically contacted. In the second contacting region, the second surface electrode is electrically connected to at least one current collecting bar. For this purpose, the at least one current collecting bar is arranged on the second surface electrode in the second contacting region.

[0014] According to the invention, the first contacting region and the second contacting region are arranged on opposite sides of the functional element. The current busbar of the first surface electrode (i.e., the current busbar arranged on the first surface electrode in the first contacting region, connected to it, and electrically connected to it) runs in a connecting region from the first contact region to the opposite side of the functional element. The connecting region, like the first contacting region, is formed by removing the second carrier film, the second surface electrode, and the active layer or layer sequence.

[0015] The contacting areas preferably have a width of 3 mm to 20 mm, particularly preferably 5 mm to 10 mm. The connection area preferably also has a width of 3 mm to 20 mm, particularly preferably 5 mm to 10 mm. The width is the dimension perpendicular to the intended extension direction of the busbars.

[0016] The functional element according to the invention is divided into

[0017] - at least one active region in which both carrier films, both surface electrodes and the active layer or layer sequence are present and in which the optical properties can be electrically controlled,

[0018] - the first and second contact area and

[0019] - the connection area.

[0020] The current busbar of the first surface electrode and the at least one current busbar of the second surface electrode (i.e., the current busbar or current busbars arranged in the second contacting region on the second surface electrode, connected to it, and electrically connected to it) are connected to a voltage source via electrical conductors. The electrical conductors are preferably connected to the current busbar of the first surface electrode and the at least one current busbar of the second surface electrode on the same side of the functional element.

[0021] The contacting regions are preferably formed directly adjacent to the side edge of the functional element. The first contacting region and the second contacting region directly border opposite sections of the side edge of the functional element.

[0022] In one embodiment, the connecting region is also formed directly adjacent to the side edge of the functional element. It directly borders a section of the side edge that extends between the sections of the side edge with the first and second contacting regions. The connecting region adjoins one end of the first contacting region and extends from there to the opposite side of the functional element.

[0023] In a further embodiment, the connecting region is not directly adjacent to the side edge of the functional element. It runs in a central region of the functional element, bordering active regions of the functional element on both sides. The connecting region adjoins a section of the first contacting region located between the ends and extends from there to the opposite side of the functional element. The connecting region divides the second surface electrode and the second contacting region into two sections, each section being assigned to an active region of the functional element.

[0024] The functional element is not restricted to a specific shape. Typically, the functional element has an at least approximately quadrangular, in particular at least approximately rectangular shape (based on the plan view in the direction of view through the composite pane). The functional element has four corners and four sides, with adjacent sides being connected to one another via a corner each. By “approximately” we mean that the shape can deviate from the ideal geometric quadrilateral or rectangle in that the sides do not have to be straight, but can, for example, be convexly or concavely curved or wavy independently of one another. The contacting regions are arranged on two opposite sides, in particular directly adjacent to the side edge or the said sides.The two additional sides extend between the sides with the contacting regions, in particular substantially perpendicular to them. The connecting region preferably extends substantially parallel to these additional sides, whereby it can be adjacent to one of the two or can extend in a region between these additional sides.

[0025] The second contacting region and the connecting region can overlap. In this case, a section of the functional element is cut off, namely the area of ​​overlap in which the surface electrodes on carrier films are removed, since the active layer or layer sequence alone is not stable. Alternatively, it is also conceivable for the second contacting region and the connecting region to abut one another directly, viewed in plan view of the functional element or the composite pane. This is the case when the cutting line for removing the first carrier film in the second contacting region and the cutting line for removing the second carrier film in the connecting region are aligned in an overlap section, viewed in plan view.

[0026] In an advantageous embodiment, however, the second contacting region and the connecting region do not overlap. The second contacting region and the connecting region also do not abut one another in the aforementioned sense. Instead, as viewed in plan view of the functional element or the composite pane, at least one intermediate region is present between the second contacting region and the connecting region. The cutting line for removing the first carrier film in the second contacting region is therefore guided to the side edge of the functional element before it reaches the connecting region. In this intermediate region, the first carrier film, the first surface electrode and the active layer or layer sequence are not removed, but extend in particular to the side edge of the functional element on the side on which the electrical connection is made.The second carrier foil and the second surface electrode also extend in the intermediate region to the side edge of the functional element on the side on which the electrical connection is made.

[0027] In a preferred variant, in the intermediate region, a part of the second surface electrode which, viewed in plan view, borders the connection region is electrically insulated from the rest of the second surface electrode by at least one insulation line. The at least one insulation line preferably runs from the side of the functional element with the second contacting region to the opposite first contacting region. The at least one insulation line divides the second surface electrode into at least one active region, in which it actually acts as a surface electrode and applies a voltage to the active layer / layer sequence, and at least one region which is electrically insulated therefrom and which, viewed in plan view, borders the connection region. The electrical insulation of the part of the second surface electrode bordering the connection region particularly reduces the risk of short circuits.This is advantageous because this part of the second surface electrode is directly adjacent to the connection region in which the first surface electrode is exposed and in which the current collecting bar runs, so that there is a risk that this part of the second surface electrode will come into contact with the first surface electrode, the current collecting bar of the first surface electrode or their electrical contacts and cause a short circuit.

[0028] The at least one insulation line for insulating the region of the second surface electrode adjacent to the connection region has, for example, a width (line width) of 5 pm to 500 pm, in particular 20 pm to 200 pm. It is preferably introduced into the second surface electrode by means of laser radiation. If the connection region borders on the side edge of the functional element, a single insulation line is sufficient, which divides the second surface electrode into an active region and a region that is electrically insulated from it and borders the connection region. If the connection region does not border on the side edge of the functional element, two insulation lines are used, which divide the second surface electrode into two active regions and two electrically insulated regions, each bordering the connection region on one side.

[0029] In one embodiment of the invention, the second surface electrode (or each of its active regions if the second surface electrode is divided into two sections by a connecting region not adjacent to the side edge of the functional element and / or a region of the second surface electrode adjacent to the connecting region is insulated from at least one active region by at least one insulation line in at least one intermediate region) is formed as a continuous, uninterrupted layer. It is not divided by insulation lines into several segments that are electrically insulated from one another. The functional element (or its active region) can then be brought into a uniform optical state by the applied electrical voltage; there are no independently controllable switching regions.The second surface electrode is preferably electrically connected to a single current collecting bar in the second contacting region. If the second surface electrode is divided into two sections by a connecting region not adjacent to the side edge of the functional element, each section is preferably electrically connected to a single current collecting bar. The second surface electrode and the first surface electrode are electrically connected to the voltage source, so that an electrical voltage can be applied between the second surface electrode on the one hand and the first surface electrode on the other hand in order to control the optical properties of the active layer / layer sequence located therebetween.

[0030] In a further embodiment of the invention, the second surface electrode (or at least one, preferably each of its active regions, if the second surface electrode is divided into two sections by a connecting region not adjacent to the side edge of the functional element and / or a region of the second surface electrode adjacent to the connecting region is insulated from at least one active region by at least one insulation line in at least one intermediate region) is divided into at least two separate electrode segments by at least one insulation line. Each electrode segment is electrically connected to a (separate or separate) current collecting bar.Each electrode segment of the second surface electrode and the first surface electrode (or its active region) are electrically connected to the voltage source, so that an electrical voltage can be applied independently between each electrode segment of the second surface electrode, on the one hand, and the first surface electrode (or its active region), on the other, to control the optical properties of the section of the active layer / layer sequence located therebetween. This allows for the realization of multiple independent switching regions whose optical properties can be electrically controlled independently of one another.

[0031] In this embodiment, the second surface electrode has at least two segments (electrode segments) separated from one another by an insulation line. The second surface electrode can be divided into several segments by several insulation lines. Each electrode segment forms a switching area of ​​the composite pane. The number of electrode segments can be freely selected by the person skilled in the art according to the requirements of the individual case. In a preferred embodiment, the insulation lines run essentially parallel to one another and extend from one side edge of the surface electrode to the opposite side edge. However, any other geometric shapes are also conceivable.

[0032] The insulation lines between the segments of the second surface electrode have a width of, for example, 5 pm to 500 pm, in particular 20 pm to 200 pm. They are preferably introduced into the second surface electrode using laser radiation. The width of the segments, i.e., the distance between adjacent insulation lines, can be suitably selected by the person skilled in the art according to the requirements of the individual case.

[0033] The electrode segments of the second surface electrode are electrically connected to the voltage source independently of one another, so that a second electrical potential (which is constant over time in the case of a direct voltage and variable over time in the case of an alternating voltage) can be applied to each electrode segment (independently of the other electrode segments), which can also be referred to as the switching potential. The first surface electrode (or its active region) is also electrically connected to the voltage source, so that a first electrical potential can be applied to the first surface electrode (or its active region) as a whole, which can also be referred to as the reference potential (“ground”). If the first and second potentials are identical, there is no voltage between the electrodes in the respective switching region (switching state 0%).If the first and second potentials are different, a voltage is applied between the electrodes in the respective switching range, creating a finite switching state (switching state up to 100%, which corresponds to the maximum change in the optical properties of the active layer / layer sequence).

[0034] The first surface electrode is preferably formed as a continuous, uninterrupted layer. The first surface electrode therefore has no insulation lines that would divide it into independent segments. A uniform electrical potential is preferably applied to the first surface electrode.

[0035] An insulation line is generally understood to be a linear or line-shaped area in which the material of the surface electrode is absent, so that the adjacent sections (segments) are materially separated from each other and therefore electrically insulated. This means that there is no direct electrical connection between the sections (segments), although the sections (segments) may be indirectly electrically connected to one another to a certain extent via the active layer in contact with them.

[0036] The busbars serve to distribute the electrical contact of the respective surface electrode with the voltage source over a comparatively large contact area and to introduce or discharge the electrical current over the largest possible width. They are also referred to as “busbars”. The busbars preferably have a width of 2 mm to 20 mm, particularly preferably of 4 mm to 9 mm. The width of the busbars is preferably smaller than the width of the contacting areas and the connection area, for example by approximately 1 mm. The busbars are preferably formed from an electrically conductive foil (in particular as a strip or section of the electrically conductive foil). The foil is particularly preferably a metal foil, in particular copper foil. The copper foil can be tinned. The metal foil has, for example, a thickness of 0.02 mm to 0.2 mm, preferably of 0.05 mm to 0.1 mm.However, polymeric carrier films can also be used which are provided with an electrically conductive coating, for example a silver coating.

[0037] The busbars can be formed independently of one another in one piece (i.e., from a single strip or section of the electrically conductive foil) or in multiple pieces (i.e., from several combined strips or sections of the electrically conductive foil). In a preferred embodiment, the busbar of the second surface electrode is formed in one piece (in particular, as a strip of the electrically conductive foil), and the busbar of the first surface electrode is formed in one piece or in multiple pieces. In the multi-piece design, the two sections of the busbar on the contacting region and the connecting region are preferably each formed in one piece and connected to one another, for example, placed on top of one another, soldered, or electrically conductively bonded.The busbar of the first surface electrode typically has an L-shaped configuration (if the connecting portion is adjacent to a side edge of the functional element) or a T-shaped configuration (if the connecting portion is not adjacent to a side edge of the functional element). In the one-piece configuration, either a T- or L-shaped section of the electrically conductive foil can be used, or a strip of the electrically conductive foil can be folded into the T- or L-shaped configuration.

[0038] The busbars are electrically connected to the associated surface electrode. The busbars can, for example, simply be placed on the surface electrode, soldered to the surface electrode, or connected to the surface electrode via an electrically conductive adhesive. In an advantageous embodiment, an electrical contact layer is arranged between the surface electrode and the busbar to improve electrical contact. The contact layer can, for example, be formed as a silver-containing paste with a thickness of 0.01 mm to 0.2 mm, preferably 0.02 mm to 0.1 mm, in particular 0.02 mm to 0.05 mm.

[0039] An electrical conductor is connected to each of the busbars of the first surface electrode and the busbar of the second surface electrode, or to the busbars of the various segments of the second surface electrode, which extends beyond the side edge of the composite pane to connect to the external voltage source. The conductor can be formed in one piece or in multiple pieces. This conductor can be, for example, a metal wire, a metal foil, and / or an electrical cable, which extends from the respective surface electrode beyond the side edge of the composite pane.

[0040] In an advantageous development of the invention, the said conductors comprise a ribbon conductor which extends beyond the side edge of the composite pane and to which the current collecting bars of the surface electrodes are connected via electrical conductors. The composite pane then has the ribbon conductor. The ribbon conductor is arranged laterally at a certain distance from the functional element, in particular on the side with the second contacting area, at which the electrical connection is made, and extends beyond the side edge of the composite pane. The current collecting bar of the first surface electrode and the at least one current collecting bar of the second surface electrode are connected to the ribbon conductor via electrical conductors. The ribbon conductor advantageously facilitates the electrical connection of the functional element.In particular, the effort of laying a number of separate cables for each individual busbar is eliminated.

[0041] The flat ribbon conductor has a plurality of electrically conductive tracks, each formed in particular from a strip of metal foil (e.g. copper foil). Preferably, all electrically conductive tracks are connected to a component by a polymer sheath or carrier layer. A conductive track is assigned to the first surface electrode and is connected to it via electrical conductors. A conductive track is assigned to the second surface electrode and is connected to it via electrical conductors, or a plurality of conductive tracks are assigned, wherein each segment of the second surface electrode is connected to a (separate) track via electrical conductors, such that each electrode segment is connected to exactly one track and each track is connected to exactly one electrode segment.The ribbon cable can of course also have tracks that are not connected to any electrode or electrode segment and are not used for electrical connection (“blind tracks”).

[0042] In a preferred embodiment of the invention, an electrical contact element is connected to each of the busbars. In other words, the busbars are each provided with an electrical contact element, wherein the contact element is, for example, placed on the busbars, soldered to them, or glued with a conductive adhesive. The electrical contact element is preferably formed from an electrically conductive foil, in particular copper foil. The copper foil can be tinned. The metal foil has, for example, a thickness of 0.02 mm to 0.2 mm, preferably of 0.05 mm to 0.1 mm. Alternatively, the contact element can be formed, for example, as a carrier foil with an electrically conductive coating, for example a silver coating.The contact element preferably has at least one section that extends from the busbar beyond the side edge of the functional element, in particular substantially perpendicular to the direction of the busbar. This section is preferably connected to the ribbon cable. The contact element can, for example, have a strip-like or T-like shape.

[0043] The contact element can be connected directly to the ribbon cable. Alternatively, the contact element can be connected indirectly to the ribbon cable via an electrical cable. The electrical cables are preferably metal wires, electrical cables, or printed circuit boards.

[0044] The contact element can also be used in cases where the electrical cables themselves extend beyond the side edge of the composite pane, i.e. where there is no common ribbon cable.

[0045] The electrically controllable functional element is a multilayer film or functional film with the actual active layer or layer sequence and the surface electrodes sandwiched between two carrier films. Such multilayer films can be purchased, cut to the desired size and shape, and then laminated into the composite pane. They are preferably bonded to the outer and inner panes via a thermoplastic bonding layer.

[0046] The first and second carrier films are based, for example, on polyethylene terephthalate (PET), polypropylene, polyvinyl chloride, fluorinated ethylene propylene, polyvinyl fluoride, or ethylene tetrafluoroethylene, preferably on PET. The thickness of the carrier films is preferably between 10 μm and 200 μm. The side edge of the functional element can be sealed, for example by fusing the carrier films or by a (preferably polymeric) tape or a polymeric film. This can protect the active layer, in particular against components of the intermediate layer (especially plasticizers) diffusing into the active layer, which can lead to degradation of the functional element.

[0047] The first and second surface electrodes are preferably transparent, which in the sense of the invention means that they have a light transmission in the visible spectral range of at least 50%, preferably at least 70%, particularly preferably at least 80%. The surface electrodes preferably contain at least one metal, a metal alloy, or a transparent conducting oxide (TCO). The surface electrodes can be formed, for example, from silver, gold, copper, nickel, chromium, tungsten, indium tin oxide (ITO), gallium-doped or aluminum-doped zinc oxide, and / or fluorine-doped or antimony-doped tin oxide, preferably based on silver or ITO. The surface electrodes preferably have a thickness of 10 nm to 2 pm, particularly preferably from 20 nm to 1 pm, most preferably from 30 nm to 500 nm.

[0048] The active layer or layer sequence exhibits variable optical properties that can be controlled by an electrical voltage applied to the active layer via the surface electrodes. 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 be switched only between two discrete states (or between more than two discrete states). These optical properties relate in particular to light transmission and / or scattering behavior.

[0049] Depending on the type of functional element, there may be a single active layer or an active layer sequence (i.e., a plurality of different layers that together provide the variable optical properties). Various types of functional elements can be used, with the functional element in preferred embodiments being a functional element based on liquid crystal technology (in particular, a PDLC functional element), an SPD functional element, or an electrochromic functional element. Functional elements based on liquid crystal technology contain an active layer with liquid crystals. The liquid crystals can be aligned by applying a voltage to the surface electrodes, on which the electrical control of the optical properties is based. In particular, the following functional elements based on liquid crystal technology are common:

[0050] PDLC (polymer dispersed liquid crystal) functional elements. The active layer contains droplets of liquid crystals in a polymer matrix. If the liquid crystals are aligned in an electric field, the state is transparent and non-light-scattering. If the liquid crystals are not aligned without an electric field, the state is translucent and strongly light-scattering.

[0051] PNLC functional elements (polymer networked liquid crystal). The active layer contains liquid crystals embedded in a polymer network. Without an applied voltage, the liquid crystals are aligned and the state is transparent and non-light-scattering. When an electrical voltage is applied, configuration changes occur, leading to strong scattering by the liquid crystals, resulting in a translucent and highly light-scattering state.

[0052] Guest-host functional elements: The active layer contains dichroic dye molecules (guest) dissolved in liquid crystals (host). In an electric field, the liquid crystals are aligned, influencing the orientation of the dye molecules, resulting in a change in transmittance (tint) and color.

[0053] SPD (suspended particle device) functional elements have an active layer containing suspended particles. 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.

[0054] Electrochromic functional elements contain an active layer sequence between the surface electrodes (electrochromic layer sequence), which comprises an ion storage layer, an electrolyte layer, and an electrochromic layer arranged one above the other in the specified order. 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 + , N / a + - or K +Ions are stored in the ion storage layer and made available by it. The electrolyte layer spatially separates the electrochromic layer from the ion storage layer and serves to facilitate the migration of ions. If a direct 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 migrated ions. If a direct 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). 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 a layer containing a mixed oxide of titanium and cerium; examples of anodic electrochromic ion storage layers are layers containing iridium oxide or nickel oxide.

[0055] A control unit suitable for operating the functional element preferably serves as the voltage source for the functional element. The control unit is suitable for applying a voltage between, on the one hand, the first surface electrode and, on the other hand, the second surface electrode or the electrode segments of the second surface electrode (in each case). Depending on the type of functional element, the voltage provided by the control unit can be a direct voltage (for example, in the case of electrochromic functional elements) or an alternating voltage (for example, in the case of SPD functional elements or PDLC functional elements or other functional elements based on liquid crystal technology). If the primary voltage source provides a direct voltage (as is common, for example, in the on-board electrical system of a vehicle) while the functional element is operated with an alternating voltage, the control unit can comprise inverters.If the primary voltage source provides an alternating voltage while the functional element is operated with a direct voltage, the control unit can include rectifiers. The control unit is designed and suitable for controlling the optical properties of the functional element. The control unit is electrically connected to the surface electrodes of the functional element and to a primary voltage source. The control unit contains the necessary electrical and / or electronic components to apply the required voltage to the surface electrodes depending on a switching state.The switching state can be specified by the user (for example, by operating a switch, a button, or a rotary or slide control), determined by sensors, and / or transmitted via a digital interface from the vehicle's central control unit (usually a LIN bus or CAN bus if the laminated pane is a vehicle window). The switches, buttons, rotary or slide controls can, for example, be integrated into the vehicle's instruments if the laminated pane is a vehicle window. However, touch buttons can also be integrated directly into the laminated pane, for example, capacitive or resistive buttons. Alternatively, the functional element can also be controlled using contactless methods, for example, by recognizing gestures, or depending on the state of the pupil or eyelid determined by a camera and suitable evaluation electronics.The control unit may include, for example, electronic processors, voltage converters, transistors and other components.

[0056] The control unit can be attached to the interior-side surface of the inner pane facing away from the intermediate layer or, for example, can be integrated into the vehicle's electrical system or can be attached to the vehicle body if the laminated pane is a vehicle pane.

[0057] The composite pane is typically intended to separate an interior space from the exterior environment in a window opening (for example a window opening in a vehicle, a building or a room). In the context of the invention, the inner pane refers to the pane facing the interior space. The outer pane refers to the pane facing the exterior space. The outer pane and the inner pane each have an outside surface and an inside surface and a circumferential side edge surface running between them. In the context of the invention, the outside surface refers to the main surface which is intended to face the outside environment in the installed position. In the context of the invention, the inside surface refers to the main surface which is intended to face the interior space in the installed position.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.

[0058] The outer pane and the inner pane are preferably made of glass, particularly preferably soda-lime glass, as is common for window panes. However, the panes can also be made of other types of glass, such as quartz glass, borosilicate glass, or aluminosilicate glass, or of rigid, clear plastics, such as polycarbonate or polymethyl methacrylate. The panes can be clear, tinted, or colored.

[0059] The thickness of the outer and inner panes can vary widely and thus be adapted to individual requirements. The outer and inner panes preferably have thicknesses of 0.5 mm to 5 mm, particularly preferably 1 mm to 3 mm. The outer and inner panes can be flat or cylindrically or spherically curved. Spherically curved laminated panes are particularly common for vehicle glazing, while flat laminated panes are used for building glazing.

[0060] The outer pane, the inner pane and / or the intermediate layer may have suitable coatings known per se, for example anti-reflective coatings, non-stick coatings, anti-scratch coatings, photocatalytic coatings, UV-absorbing or reflective coatings or IR-absorbing or reflective coatings such as sunscreen coatings or low-E coatings.

[0061] The composite pane can be provided with an opaque masking print, in particular at least in a circumferential edge region, as is common in the automotive sector, particularly for windshields, rear windows, and roof windows. The masking print is typically formed from an enamel containing glass frits and a pigment, in particular black pigment. The printing ink is typically applied using a screen printing process and baked in. Such a masking print is applied to at least one of the pane surfaces, preferably the interior-side surface of the outer pane and / or the inner pane. The masking print preferably surrounds a central see-through region in a frame-like manner. The masking print forms an opaque masking region of the composite pane. The contact regions and the connection region of the functional element are preferably arranged in this masking region.

[0062] The thermoplastic intermediate layer serves to connect the two panes, as is usual with composite panes. Typically, thermoplastic films are used, and the intermediate layer is formed from these. In a preferred embodiment, the functional element is arranged between two thermoplastic layers. The intermediate layer is formed from at least a first thermoplastic layer and a second thermoplastic layer, between which the functional element is arranged. The functional element is then connected to the outer pane via a region of the first thermoplastic layer and to the inner pane via a region of the second thermoplastic layer. The thermoplastic layers preferably protrude circumferentially beyond the functional element.Where the thermoplastic layers are in direct contact with each other and are not separated by the functional element, they can fuse during lamination to such an extent that the original layers may no longer be recognizable and a homogeneous intermediate layer is present instead.

[0063] A thermoplastic layer can, for example, be formed from a single thermoplastic film. A thermoplastic layer can also be formed from sections of different thermoplastic films whose side edges are joined together.

[0064] In a preferred embodiment, the functional element, or more precisely the side edges of the functional element, is surrounded all the way around by a third thermoplastic layer. The third thermoplastic layer is frame-like with a recess into which the functional element is inserted. The third thermoplastic layer can be formed by a thermoplastic film into which the recess has been cut. Alternatively, the third thermoplastic layer can also be composed of several film sections around the functional element. The intermediate layer is then formed from a total of at least three thermoplastic layers arranged flat on top of one another, with the middle layer having a recess in which the functional element is arranged.During production, the third thermoplastic layer is arranged between the first and second thermoplastic layers, with the side edges of all thermoplastic layers preferably aligned. The third thermoplastic layer preferably has approximately the same thickness as the functional element. This compensates for the local thickness difference introduced by the localized functional element, preventing glass breakage during lamination and resulting in an improved visual appearance.

[0065] Alternatively, the functional element can also be arranged directly on the surface of the outer pane or the inner pane facing the intermediate layer. Preferably, the side edge of the functional element is completely surrounded by the intermediate layer, so that the functional element does not extend to the side edge of the composite pane and thus has no contact with the surrounding atmosphere. Here, too, the use of a frame-like thermoplastic layer around the functional element is possible.

[0066] The thermoplastic layers of the intermediate layer are preferably made of the same material, but can in principle also be made of different materials. The layers or films of the intermediate layer are preferably based on polyvinyl butyral (PVB), ethylene-vinyl acetate (EVA), or polyurethane (PU). This means that the layer or film predominantly contains the said material (a proportion of greater than 50% by weight) and can optionally contain other components, for example, plasticizers, stabilizers, UV or IR absorbers. The thickness of each thermoplastic layer is preferably from 0.2 mm to 2 mm, particularly preferably from 0.3 mm to 1 mm. For example, films with standard thicknesses of 0.38 mm or 0.76 mm can be used.

[0067] The composite pane can be manufactured by stacking the individual layers in the intended sequence to form a stack of layers, and then laminating the outer pane and the inner pane together via the intermediate layer. Known processes can be used for this, such as autoclave processes, vacuum bag processes, vacuum ring processes, calender processes, vacuum laminators, or combinations thereof. The bonding of the outer pane and inner pane is typically achieved under the influence of heat, vacuum, and / or pressure.

[0068] The layer stack preferably comprises in the order given: the outer pane - a first thermoplastic film which forms a first thermoplastic layer of the intermediate layer,

[0069] - the functional element, preferably enclosed in a frame-like third thermoplastic film with a recess,

[0070] - a second thermoplastic film forming a second thermoplastic layer of the intermediate layer,

[0071] - the inner pane.

[0072] When stacking the layers, the functional element is provided with the required electrical connections, with electrical conductors extending beyond the side edge of the layer stack, to which the external voltage source can later be provided.

[0073] In an advantageous embodiment, the functional element is provided with the current collecting bars, which are connected to the surface electrodes, optionally via an electrical contact layer. The electrical conductors are provided on the thermoplastic films and suitably positioned so that when the layer stack is created, the electrical conductors come into contact with the current collecting bars without further measures. The electrical conductors preferably comprise a flat strip conductor, which is arranged laterally of the functional element, an electrical contact element for direct connection to the current collecting bars, and electrical lines (in particular wires or cables) between each contact element and a conductor track of the flat strip conductor. The electrical conductors are each attached to the thermoplastic film, opposite which the surface electrode, which is to be contacted with the conductors, is exposed.If, for example, the first carrier film with the first surface electrode faces the first thermoplastic film, the first surface electrode is exposed to the second thermoplastic film in the first contact region: in the first contact region, only the first carrier film and the first surface electrode are present, with the first surface electrode facing the second thermoplastic layer.

[0074] The invention further encompasses the use of a laminated pane according to the invention in buildings or in means of transport for land, air, or water traffic, for example as a window pane of a vehicle, as a window pane of a building or a room (building interior), or as a component of furniture, electrical devices, or furnishings. The laminated pane is preferably the window pane of a vehicle, in particular a motor vehicle. The glazing unit can be used, for example, as a windshield, roof pane, rear window pane, or side window, preferably as a windshield or roof pane.

[0075] In a particularly preferred embodiment, the composite pane is a windshield of a vehicle. The functional element is preferably used as an electrically controllable sun visor, which is arranged in an upper region of the windshield, while the majority of the windshield is not provided with the functional element. There can be several switching areas, which are preferably arranged essentially parallel to the upper edge of the windshield with increasing distance from it. By means of the independently switchable switching areas, the user can determine, depending on the position of the sun, the extent of the area adjacent to the upper edge that is to be darkened or provided with a high level of light scattering in order to avoid glare from the sun.

[0076] In a further preferred embodiment, the composite pane is a roof pane of a vehicle. The functional element is preferably arranged across the entire view-through area of ​​the composite pane. In a typical embodiment, this view-through area comprises the entire composite pane minus a peripheral edge area provided with an opaque cover print on at least one of the surfaces of the panes. The functional element extends across the entire view-through area, with its side edges arranged in the area of ​​the opaque cover print and thus not visible to the observer. There may be several switching areas, which are preferably arranged essentially parallel to the front edge of the roof pane with increasing distance from it.Thanks to the independently switchable switching areas, the user can specify which areas of the roof window should be transparent and which should be darkened or provided with a high degree of light diffusion, for example, depending on the position of the sun to prevent excessive heating of the vehicle interior. It is also possible for each vehicle occupant, for example the driver, the front passenger, the left and right rear occupants, to be assigned a switching area located above them. 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:

[0077] Fig. 1 shows a cross section of an embodiment of the composite pane according to the invention, Fig. 2 shows a cross section through the functional element of the composite pane from Fig. 1, Fig. 3 shows a plan view of the functional element from Fig. 2,

[0078] Fig. 4 is a plan view of the functional element of a further embodiment of the composite pane according to the invention,

[0079] Fig. 5 is a plan view of the functional element of a further embodiment of the composite pane according to the invention and

[0080] Fig. 6 is a plan view of the functional element of a conventional composite pane.

[0081] Figure 1 shows a cross-section of the composite pane according to the invention with electrically controllable optical properties. The composite pane is intended, by way of example, as the roof pane of a passenger car, the light transmission of which can be electrically controlled. The composite pane comprises an outer pane 1 and an inner pane 2, which are connected to one another via an intermediate layer 3. The outer pane 1 and the inner pane 2 are made of soda-lime glass, which can optionally be tinted. The outer pane 1 has a thickness of 2.1 mm, for example, and the inner pane 2 has a thickness of 1.6 mm.

[0082] The intermediate layer 3 comprises a total of three thermoplastic layers 3a, 3b, 3c, each formed by a thermoplastic PVB film with a thickness of 0.38 mm. The first thermoplastic layer 3a is connected to the outer pane 1, the second thermoplastic layer 3b to the inner pane 2. The intermediate third thermoplastic layer 3c has a cutout into which a functional element 10 with electrically controllable optical properties is inserted with a substantially precise fit, i.e. approximately flush on all sides. The third thermoplastic layer 3c thus forms a type of passe-partout or frame for the approximately 0.4 mm thick functional element 10, which is thus encapsulated all around in thermoplastic material and thus protected. The composite pane has a circumferential edge region provided with an opaque cover print 4. This cover print 4 is typically made of black enamel.It is printed as a printing ink with a black pigment and glass frits using a screen printing process and baked into the pane surface. The cover print 4 is applied, for example, to the interior surface of the outer pane 1 and also to the interior surface of the inner pane 2. The side edges of the functional element 10 are concealed by this cover print 4.

[0083] For the sake of clarity, Figure 2 shows a cross-section through the functional element 10 from Figure 1 alone. The functional element 10 is, for example, a PDLC multilayer film that can be switched from a clear, transparent state to a cloudy, non-transparent (diffuse) state. The functional element 10 consists of an active layer 11 between a first surface electrode 14 and a second surface electrode 15. The first surface electrode 14 is applied to a first carrier film 12, and the second surface electrode 15 is applied to a second carrier film 13. The active layer 11 contains a polymer matrix with liquid crystals dispersed therein, which align themselves depending on the electrical voltage applied to the surface electrodes 14, 15, whereby the optical properties can be controlled. The carrier films 12, 13 are made of PET and have a thickness of, for example, 0.125 mm.The carrier foils 12, 13 are each provided with an ITO coating facing the active layer 11 with a thickness of approximately 100 nm, which forms the surface electrodes 14, 15.

[0084] The functional element 10 has a first contacting region in which the first surface electrode 14 is exposed for connection to the voltage source. In the first contacting region, the second carrier foil 13, the second surface electrode 15, and the active layer 11 are removed. In the first contacting region, a current collecting bar 21 is arranged on the first surface electrode 14 via an electrical contact layer 23.

[0085] The functional element 10 has a second contacting region in which the second surface electrode 15 is exposed for connection to the voltage source. In the second contacting region, the first carrier film 12, the first surface electrode 14, and the active layer 11 are removed. In the second contacting region, a current collecting bar 22 is arranged on the second surface electrode 15 via an electrical contact layer 23. Figure 3 shows a plan view of the functional element 10 from Figure 2. The second carrier film 13 is facing the viewer. The functional element has a rectangular shape with four straight side sections and four corners.

[0086] The first contacting area extends along the left side section and directly borders the side edge of the functional element 10. There, the second carrier foil 13 with the second surface electrode 15 and the active layer 11 are removed, so that the exposed first surface electrode 14 on the first carrier layer 12 can be seen (shown in dotted lines).

[0087] The second contacting area extends along the right side section and directly borders the side edge of the functional element 10. The first carrier foil 12 with the first surface electrode 14 and the active layer 11 have been removed there. The second surface electrode 15 is not visible here because it is concealed by the second carrier foil 13 located above. The left boundary of the second contacting area (section line) is indicated by a thin dashed line.

[0088] In the second contacting area, the current busbar 22 is arranged on the second surface electrode 15. It is shown with a dashed outline and in gray because it lies behind the second carrier foil 13 and is therefore only visible when viewed through it. In the first contacting area, the current busbar 21 is arranged on the first surface electrode 14.

[0089] Adjacent to the lower side edge, a connection region runs from the first contacting region to the opposite right side section of the functional element 10. In the connection region, as in the first contacting region, the second carrier film 13, the second surface electrode 15 and the active layer 11 are removed, so that the first surface electrode 14 is exposed.

[0090] A section of the busbar 21 of the first surface electrode 14 is arranged in the first contacting area. Another section is arranged in the connection area, extending from the first contacting area to the opposite right side section of the functional element 10. This has the advantage that both busbars 21, 22 can be electrically connected to the same side of the functional element 10, namely the right side section.

[0091] The dashed outline of the second contacting region corresponds to the cutting line for removing the first carrier foil 12. In the plan view shown, it is located below the second contacting region toward the side edge of the functional element in the right-hand side section before reaching the connection region. This creates an intermediate region between the second contacting region and the connection region in which the first carrier foil 12, the first surface electrode 14, and the active layer 11 are not removed.

[0092] For electrical connection to the external voltage source, the composite pane is equipped with a ribbon conductor 27, which is arranged to the side of the functional element 10, spaced from the right-hand side section. The ribbon conductor 27 extends beyond the side edge of the composite pane. A T-shaped electrical contact element 25 is arranged on the current collecting bar 22 of the second surface electrode 15 and is directly connected to the ribbon conductor 27. The majority of the contact element 25 is again shown with a dashed outline and in gray because it is located behind the second carrier film 13 and the current collecting bar 22. A strip-like electrical contact element 24 is arranged in the connection area on the current collecting bar 21 of the first surface electrode 14 and is directly connected to the ribbon conductor 27.Each contact element 24, 25 is connected to one of two conductor tracks of the ribbon conductor 27, which is not shown for the sake of simplicity.

[0093] The busbars have a width of 5 mm, for example. They are made of a copper foil with a thickness of, for example, 50 μm. The electrical contact layers 23 consist, for example, of a silver paste with a thickness of 50 μm. The electrical contact elements 24, 25 are also made of a copper foil with a thickness of, for example, 50 μm.

[0094] In the intermediate region between the second contact region and the connection region, a portion of the second surface electrode 15 is electrically insulated from the remaining second surface electrode 15 by an insulation line 16. The insulation line 16 divides the second surface electrode 15 into an active region, which acts as the actual surface electrode, and a region insulated therefrom, which borders the connection region. This reduces the risk of a short circuit, since the portion of the second surface electrode 15 bordering the connection region can easily come into contact with the first surface electrode 14 or its busbar 21. The insulation line 16 is introduced into the second surface electrode 15 by laser radiation and has a line width of, for example, 100 pm.

[0095] Figure 4 shows a top view of the functional element 10 in a further embodiment of the composite pane according to the invention. The functional element 10 is fundamentally constructed in the same way as in the embodiment of Figures 2 and 3. In contrast, the functional element 10 has three independent switching areas in which the switching state can be adjusted independently of one another. Using the switching areas, the driver of the vehicle can choose (for example, depending on the position of the sun) to provide only one area of ​​the composite pane with the diffuse state instead of the entire composite pane, while the other areas remain transparent.

[0096] For this purpose, the second surface electrode 15 is divided into three electrode segments 15.1, 15.2, 15.3 by two insulation lines 15'. The insulation lines 15' are introduced into the surface electrode 15 by laser radiation and have a line width of, for example, 100 pm. Each electrode segment 15.1, 15.2, 15.3 is connected to the voltage source independently of the others. A control unit is suitable for independently applying an electrical voltage between each electrode segment 15.1, 15.2, 15.3 of the second surface electrode 15, on the one hand, and the first surface electrode 14, on the other hand, so that the section of the active layer 11 located therebetween is subjected to the required voltage in order to achieve a desired switching state.

[0097] Each electrode segment 15.1, 15.2, 15.3 is provided in the second contact area with a current collecting bar 22.1, 22.2, 22.3, which in turn is provided with an electrical contact element 25.1, 25.2, 25.3. In contrast to the embodiment in Figures 2 and 3, the contact elements 24, 25.1, 25.2, 25.3 are not connected directly to the ribbon conductor 27, but rather via an electrical line 26 connected thereto. The ribbon conductor 27 has at least four conductor tracks, with each current collecting bar 21, 22.1, 22.2, 22.3 being connected to a separate conductor track. The electrical lines 26 are designed, for example, as tungsten wires with a diameter of 150 pm.

[0098] Another difference from the design shown in Figures 2 and 3 is the shape of the dashed outline of the second contact area. This outline does not form a right angle below the second contact area, which is intended to be routed to the right-hand side section. Instead, it forms a curve, which is technically easier to implement.

[0099] In this embodiment too, in the intermediate region between the second contact region and the connection region, a portion of the second surface electrode 15 is electrically insulated from the remaining second surface electrode 15 by an insulation line 16. The insulation line 16 divides the second surface electrode 15 into an active region, which acts as the actual surface electrode and is divided into three independent segments 15.1, 15.2, 15.3, and a region insulated therefrom, which borders the connection region. This reduces the risk of a short circuit, since the portion of the second surface electrode 15 bordering the connection region can easily come into contact with the first surface electrode 14 or its busbar 21. The insulation line 16 is introduced into the second surface electrode 15 by laser radiation and has a line width of, for example, 100 pm.Since the functional element 10 is already subjected to a laser process to produce the insulation lines 15', the production of the insulation line 16 only requires a small additional effort.

[0100] Figure 5 shows a top view of the functional element 10 in a further embodiment of the composite pane according to the invention. The functional element 10 is fundamentally constructed in the same way as in the embodiment of Figures 2 and 3. In contrast, the connecting area is not arranged adjacent to the lower side section, but rather in a central area of ​​the functional element 10.

[0101] Since the second carrier film 13 with the second surface electrode 15 and the active layer 11 have been removed in the connection region, the functional element is divided by the connection region into two switching regions in which the optical properties can be electrically controlled. The carrier films 12, 13, the surface electrodes 14, 15 and the active layer 11 are completely present in the switching regions. The second surface electrode 15 is divided by the connection region into two electrode segments 15.1, 15.2. The second contact region is also divided into two sections. Each electrode segment 15.1, 15.2 is provided in the second contact region with a current collecting bar 22.1, 22.2, which in turn is connected to the ribbon conductor 27 via a respective electrical contact element 25.1, 25.2 and an electrical line 26 connected thereto. The ribbon conductor 27 has at least three conductor tracks, each busbar 21, 22.1, 22.2 is connected to a separate conductor track each.

[0102] Between each section of the second contact region and the connection region, in the plan view shown, an intermediate region is again arranged, in which the first carrier foil 12, the first surface electrode 14, and the active layer 11 are not removed. In each intermediate region, an insulation line 16 is arranged, which divides the respective section of the second surface electrode 15 into an active section and a section insulated from it and adjacent to the connection region, which serves to prevent short circuits in the connection region.

[0103] For comparison, Figure 6 shows a top view of the functional element 10 in a conventional design of a composite pane of this type. As in Figure 4, the functional element 10 is divided into three independent switching areas.

[0104] The electrical connection is made via electrical lines 26, which extend from the respective busbar beyond the side edge of the composite pane. The busbar 21 of the first surface electrode 14 is connected to the left side of the functional element 10, and the busbars 22.1, 22.2, 22.3 are connected to the right side of the functional element 10. However, since the lines 26 are intended to exit the composite pane at approximately the same point, as they are typically combined with a common connector to connect them to the voltage source, the line 26 of the busbar 21 is routed around the functional element 10. Therefore, longer lines 26 are required than in the inventive design, and their installation requires more time. List of reference symbols:

[0105] (1) Outer pane

[0106] (2) Inner pane

[0107] (3) thermoplastic intermediate layer

[0108] (3a) first layer of the intermediate layer 3

[0109] (3b) second layer of the intermediate layer 3

[0110] (3c) third layer of the intermediate layer 3

[0111] (4) Cover printing

[0112] (10) electrically controllable functional element

[0113] (11) active layer of the functional element 4 layer sequence with electrically controllable optical properties

[0114] (12) first carrier film of the functional element 4

[0115] (13) second carrier film of the functional element 4

[0116] (14) first surface electrode of the functional element 4

[0117] (15) second surface electrode of the functional element 4

[0118] (15.1 , 15.2, 15.3) Electrode segments of the second surface electrode 15

[0119] (15') Insulation line between two electrode segments 15.1, 15.2, 15.3

[0120] (16) Insulation line

[0121] (21) Current collecting bar of the first surface electrode 14

[0122] (22) Current collecting bar of the second surface electrode 15

[0123] (22.1 , 22.2, 22.3) first, second, third busbar of the second

[0124] Surface electrode 15

[0125] (23) electrical contact layer

[0126] (24) electrical contact element of the busbar 21

[0127] (25) electrical contact element of the busbar 22

[0128] (25.1 , 25.2, 25.3) electrical contact element of the first, second, third

[0129] Current collecting bar of the second surface electrode 15

[0130] (26) electrical line

[0131] (27) Flat ribbon cable

[0132] X - X' intersection line

Claims

Patent claims 1. A composite pane with electrically controllable optical properties, comprising an outer pane (1) and an inner pane (2) which are connected to one another via a thermoplastic intermediate layer (3), an electrically controllable functional element (10) embedded in the intermediate layer (3), which has, in the specified order, a first carrier film (12), a first surface electrode (14), an active layer (11) or layer sequence with electrically controllable optical properties, a second surface electrode (15) and a second carrier film (13), wherein in a first contacting region the second carrier film (13), the second surface electrode (15) and the active layer (11) or layer sequence are removed and the first surface electrode (14) is electrically conductively connected to a current collecting rail (21) and in a second contacting region the first carrier film (12),the first surface electrode (14) and the active layer (11) or layer sequence are removed and the second surface electrode (15) is electrically conductively connected to at least one current collecting bar (21; 22.1, 22.2, 22.3), wherein the first contacting region and the second contacting region are arranged on opposite sides of the functional element (10), wherein the current collecting bar (21) of the first surface electrode (14) runs in a connecting region from the first contacting region to the opposite side of the functional element (10), wherein the second carrier film (13), the second surface electrode (15) and the active layer (11) or layer sequence are removed in the connecting region, characterized in that an intermediate region is present between the second contacting region and the connecting region, in which intermediate region the first carrier film (12),the first surface electrode (14) and the active layer (11) or layer sequence are not removed, and wherein in the intermediate region a part of the second, Surface electrode (15) adjacent to the connection area by a Insulation line (16) is electrically insulated from the remaining second surface electrode (15).

2. Composite pane according to claim 1, wherein the current collecting bar (21) of the first surface electrode (14) and the at least one current collecting bar (21; 22.1, 22.2, 22.3) of the second surface electrode (15) are connected to a voltage source via electrical conductors (24, 25, 26, 27), and wherein the electrical conductors (24, 25, 26, 27) are connected on the same side of the functional element (10) to the current collecting bar (21) of the first surface electrode (14) and the at least one current collecting bar (21; 22.1, 22.2, 22.3) of the second surface electrode (15).

3. Composite pane according to claim 1 or 2, wherein the second surface electrode (15) is divided into at least two separate electrode segments (15.1, 15.2, 15.3) by at least one insulation line (15'), and wherein each Electrode segment (15.1, 15.2, 15.3) is electrically connected to a respective current collecting bar (22.1, 22.2, 22.3).

4. Composite pane according to one of claims 1 to 3, wherein the insulation line (16) or each insulation line (15', 16) has a width of 5 pm to 500 pm.

5. Composite pane according to one of claims 1 to 4, wherein the functional element (10) has an at least approximately quadrangular, in particular at least approximately rectangular shape.

6. Composite pane according to one of claims 1 to 5, wherein the functional element (10) is a functional element based on liquid crystal technology, in particular a PDLC functional element, an SPD functional element or an electrochromic functional element.

7. Composite pane according to one of claims 1 to 6, wherein the current collecting rails (21, 22, 22.1, 22.2, 22.3) are formed from an electrically conductive foil, in particular copper foil.

8. Composite pane according to one of claims 1 to 7, wherein the surface electrodes (14, 15) are formed on the basis of indium tin oxide (ITO) or silver.

9. Composite pane according to one of claims 1 to 8, which has a flat strip conductor (27) which is arranged laterally of the functional element (10) and extends beyond the side edge of the composite pane, wherein the current collecting bar (21) of the first surface electrode (14) and the at least one current collecting bar (22; 22.1, 22.2, 22.3) of the second surface electrode (15) are electrically conductively connected to the flat strip conductor (27).

10. Composite pane according to claim 9, wherein the current collecting rails (21, 22, 22.1, 22.2, 22.3) are each provided with an electrical contact element (24, 25, 25.1, 25.2, 25.3) which is formed from an electrically conductive foil, in particular copper foil, and is connected to the ribbon conductor (27) directly or via a respective electrical line (26), wherein the electrical lines (26) are formed as metal wires, electrical cables or printed lines.

11. Composite pane according to one of claims 1 to 10, wherein the carrier films (12, 13) are based on polyethylene terephthalate (PET) and preferably have a thickness of 10 pm to 200 pm.

12. Composite pane according to one of claims 1 to 11, wherein the functional element (10) is arranged between two thermoplastic layers (3a, 3b), which are preferably based on polyvinyl butyral (PVB), ethylene-vinyl acetate (EVA) or polyurethane (PU) and preferably have a thickness of 0.2 mm to 2 mm.

13. Composite pane according to one of claims 1 to 12, wherein the outer pane (1) and the inner pane (2) are made of soda-lime glass and preferably have a thickness of 0.5 mm to 5 mm.

14. Use of a composite pane according to one of claims 1 to 13 as a window pane of a vehicle, in particular as a windscreen or roof pane, as a window pane of a building or an interior space or as a component of furniture, electrical appliances or furnishings.

Images