Composite glass sheet with electrically controllable optical properties

Abstract

The invention relates to a composite pane having electrically controllable optical properties, comprising an electrically controllable functional element (10), which has, in a specified sequence, a first carrier film (12), a first planar electrode (14), an active layer (11) or layer sequence having electrically controllable optical properties, a second planar electrode (15) and a second carrier film (13). In the first contact region, the second carrier film (13), the second planar electrode (15) and the active layer (11) or the layer sequence are removed, and the first planar electrode (14) is connected to the bus bar (21) in an electrically conductive manner. In a second contact region, the first carrier membrane (12), the first planar electrode (14) and the active layer (11) or the layer sequence are removed, and the second planar electrode (15) is electrically conductively connected to the at least one collector rail (21; 22.1, 22.2, 22.3) in the first direction. According to the invention, the first contact region and the second contact region are arranged on opposite sides of the functional element (10), and the collector rail (21) of the first planar electrode (14) extends in a connection region from the first contact region to the opposite side of the functional element (10), in which connection region the second carrier film (13), the second planar electrode (15) and the active layer (11) or the layer sequence are removed. An intermediate region is present between the second contact region and the connection region, in which the first carrier film (12), the first planar electrode (14) and the active layer (11) or the layer sequence are not removed, and in which a portion of the second planar electrode (15) adjoining the connection region is electrically insulated from the remainder of the second planar electrode (15) by an insulating wire (16).

Description

[0001] The present invention relates to a composite glass sheet with electrically controllable optical properties and uses thereof.

[0002] Composite glass panels with electrically controllable optical properties are known per se. They are equipped with a functional element comprising an active layer or layer sequence between two planar electrodes, wherein the optical properties of the active layer or layer sequence can be altered by applying a voltage to the planar electrodes. An example of such a functional element is an SPD (suspended particle device) functional element, known, for example, from EP 0876608 B1 and WO 2011033313 A1. By applying a voltage, the transmission of visible light can be controlled by an SPD functional element. Another example is a PDLC (polymer dispersed liquid crystal) functional element, known, for example, from DE 102008026339 A1. The active layer comprises liquid crystals embedded in a polymer matrix. If no voltage is applied, the liquid crystals align in a disordered manner, resulting in strong scattering of light passing through the active layer. If a voltage is applied to the planar electrodes, the liquid crystals align in a common direction, and the transmission of light through the active layer increases. PDLC functional elements operate primarily by increasing scattering rather than reducing total transmission, thus preventing a clear view or ensuring anti-glare protection. Furthermore, electrochromic functional elements are known, for example, from US 20120026573 A1, WO 2010147494 A1 and EP 1862849 A1 and WO 2012007334 A1, in which the change in transmission is the result of an electrochemical process caused by an applied voltage.

[0003] Such composite glass panels can be used, for example, as vehicle window panes, whose light transmission behavior can then be electrically controlled. They can be used, for example, as roof panes to reduce exposure to direct sunlight or destructive reflections. Such roof panes are known, for example, from DE 10043141 A1 and EP 3456913 A1. Windshields have also been proposed in which electrically controllable sunshades are implemented by switchable functional elements to replace conventional mechanically foldable sunshades in motor vehicles. Windshields with electrically controllable sunshades are known, for example, from DE 102013001334 A1, DE 102005049081 B3, DE 102005007427 A1, and DE 102007027296 A1. Such composite glass panels can be used not only in the automotive sector, but also in, for example, architectural glazing or interior window panes.

[0004] The electrically controlled functional elements are usually provided as a multilayer film and embedded in the middle layer of the composite glass pane. The multilayer film consists of two carrier films, usually based on PET, on which planar electrodes, usually based on ITO, are deposited, with an active layer or layer sequence in between. For electrical contact, a contact area is usually created for each planar electrode by removing the opposing carrier film from the other planar electrode and the active layer or layer sequence. This leaves the planar electrodes exposed in the contact area and allows electrical contact to be made via current collector rails (usually copper foil strips). Electrical conductors are connected to the collector rails and extend beyond the lateral edges of the composite glass pane to connect the functional elements to an external voltage source.

[0005] The contact areas of the two planar electrodes are typically formed on opposite sides of the functional element. This is beneficial for the optical behavior of the functional element, particularly because it ensures more uniform and sometimes faster switching behavior. However, this fact presents disadvantages in terms of manufacturing. Since the electrical contacting steps are performed on opposite sides of the functional element, production costs increase. In particular, relatively long electrical conductors are required, for example, which are applied as metal wires using a plotter to the thermoplastic film of the intermediate layer of the composite glass pane, which is time-consuming.

[0006] DE 202018102520 U1 discloses a composite glass pane having an electrically controllable functional element, the contact areas of which are arranged on opposite sides of the functional element. The collecting rails have an L-shape, so that the collecting rails of the first planar electrode extend in a connection area starting from the first contact area to the opposite side of the functional element. This allows the electrical conductor to be connected to two collecting rails on the same side of the functional element. Since the second carrier film, the second planar electrode, and the active layer or layer sequence must be removed in the connection area to arrange the collecting rails on the first planar electrode, and the second planar electrode then directly adjoins the connection area in which the first planar electrode is exposed, there is a risk that the second planar electrode will come into contact with the first planar electrode, the collecting rails of the first planar electrode, or their electrical contacts and cause a short circuit.

[0007] The present invention addresses the problem of providing an improved composite glass pane with electrically controllable optical properties, which is in particular easier to produce and in which short circuits are avoided.

[0008] This problem is solved according to the invention by a composite glass pane having electrically controllable optical properties according to independent claim 1. Advantageous embodiments result from the dependent claims.

[0009] The present invention is based on a method of extending one of the collecting rails and guiding it in the connection area to the opposite side of the functional element, where the other collecting rail is also located. The electrical connection of the two collecting rails can then be made on the same side of the functional element, which reduces production steps (effort). This also means that fewer long electrical conductors are required, making their design more rapid, for example using a plotter. These are significant advantages of the present invention.

[0010] The composite glass pane having electrically controllable optical properties according to the present invention comprises an outer glass pane and an inner glass pane connected to each other via a thermoplastic interlayer. The composite glass pane also comprises an electrically controllable functional element embedded in the interlayer. The functional element comprises, in the specified order, a first carrier film, a first planar electrode, an active layer or layer sequence having electrically controllable optical properties, a second planar electrode, and a second carrier film. The carrier film, the planar electrode, and the active layer / layer sequence are typically arranged substantially parallel to the surfaces of the outer and inner glass panes.

[0011] The functional element has a first contact region for electrically connecting the first planar electrode. In the first contact region, the second carrier film, the second planar electrode, and the active layer or layer sequence are removed. The first carrier film and the first planar electrode remain in the first contact region, leaving the first planar electrode exposed and electrically contactable. In the first contact region, the first planar electrode is electrically conductively connected to a current collecting rail. For this purpose, the current collecting rail is arranged in the first contact region on the first planar electrode.

[0012] The functional element also has a second contact region for electrically connecting the second planar electrode. In the second contact region, the first carrier film, the first planar electrode, and the active layer or layer sequence are removed. The second carrier film and the second planar electrode remain in the second contact region, leaving the second planar electrode exposed and electrically contactable. In the second contact region, the second planar electrode is electrically conductively connected to at least one current collecting rail. For this purpose, at least one current collecting rail is disposed in the second contact region on the second planar electrode.

[0013] According to the present invention, the first and second contact regions are arranged on opposite sides of the functional element. The current collecting rail of the first planar electrode (i.e., the current collecting rail arranged in the first contact region on the first planar electrode, connected to the first planar electrode, and electrically conductively connected to the first planar electrode) extends in the connection region from the first contact region to the opposite side of the functional element. Forming the connection region is completely analogous to the first contact region, as the second carrier film, the second planar electrode, and the active layer or layer sequence are removed.

[0014] The contact region preferably has a width of 3 mm to 20 mm, particularly preferably 5 mm to 10 mm. The connection region preferably 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 collecting rail.

[0015] The functional elements according to the present invention are divided into

[0016] at least one active region in which two carrier films, two planar electrodes and an active layer or layer sequence are present and in which the optical properties can be electrically controlled,

[0017] - first and second contact areas, and

[0018] -Connection area.

[0019] The current collecting rails of the first planar electrode and at least one current collecting rail of the second planar electrode (i.e., one or more current collecting rails arranged in the second contact region on the second planar electrode, connected to the second planar electrode, and electrically conductively connected to the second planar electrode) are connected to a voltage source via electrical conductors. The electrical conductors are preferably connected to the current collecting rails of the first planar electrode and to the at least one current collecting rail of the second planar electrode on the same side of the functional element.

[0020] The contact region is preferably formed directly adjacent to a lateral edge of the functional element.The first contact region and the second contact region directly adjoin opposite portions of the lateral edge of the functional element.

[0021] In one embodiment, the connection region is also formed directly adjacent to the lateral edge of the functional element. It directly adjoins the lateral edge portion extending between the lateral edge portions having the first and second contact regions. The connection region is connected to one end of the first contact region and extends from there to the opposite side of the functional element.

[0022] In another embodiment, the connection region is not formed directly adjacent to the lateral edges of the functional element. Instead, it extends in the central region of the functional element, where it abuts on both sides of the active area of ​​the functional element. The connection region is connected to a portion of the first contact region located between the ends and extends from there to the opposite side of the functional element. The connection region divides the second planar electrode and the second contact region into two parts, each of which is assigned to the active area of ​​the functional element.

[0023] The functional element is not limited to a specific shape. Typically, the functional element has an at least approximately quadrilateral, in particular an at least approximately rectangular shape (relative to a plan view in the direction of view through the composite glass panel). The functional element has four corners and four sides, wherein adjacent sides are each connected to each other by a corner. The term "approximately" means that the shape can deviate from the ideal geometric quadrilateral or rectangle, because the sides do not have to be straight, but can, for example, convex or concave or wavy curved independently of each other. The contact area is arranged on two opposing sides, in particular directly adjacent to the lateral edge or the side. The other two sides extend between the sides with the contact area, in particular substantially perpendicular to them. The connection area preferably extends substantially parallel to these other sides, wherein it can be adjacent to one of the two sides, or can extend in the area between these other sides.

[0024] The second contact region and the connection region can overlap. This means that a portion of the functional element is cut, i.e., the overlapping region of the carrier film with the planar electrode located thereon is removed, since the active layer or layer sequence alone is unstable. Alternatively, it is also conceivable that, viewed in a plan view of the functional element or composite glass pane, the second contact region and the connection region directly adjoin one another. This is the case when, viewed in plan view, the cutting lines for removing the first carrier film in the second contact region and the cutting lines for removing the second carrier film in the connection region are arranged in layers in the overlapping portion.

[0025] However, in advantageous embodiments, the second contact region and the connection region do not overlap. In the aforementioned sense, the second contact region and the connection region do not abut one another. Instead, when viewing the functional element or the composite glass pane from above, at least one intermediate region exists between the second contact region and the connection region. Therefore, the cutting line used to remove the first carrier film in the second contact region is directed to the lateral edge of the functional element before reaching the connection region. In this intermediate region, the first carrier film, the first planar electrode, and the active layer or layer sequence are not removed, but rather extend to the lateral edge of the functional element on the side where the electrical connection is made. The second carrier film and the second planar electrode also extend in the intermediate region to the lateral edge of the functional element on the side where the electrical connection is made.

[0026] In a preferred embodiment, in the intermediate region, a portion of the second planar electrode adjacent to the connection region, as viewed in plan, is electrically insulated from the remaining second planar electrode by at least one insulating line. The at least one insulating line preferably extends from one side of the functional element having the second contact region to the opposite first contact region. The at least one insulating line divides the second planar electrode into at least one active region (wherein it actually functions as a planar electrode and applies a voltage to the active layer / layer sequence) and at least one region electrically insulated therefrom (and adjacent to the connection region, as viewed in plan). The electrical insulation of the portion of the second planar electrode adjacent to the connection region particularly reduces the risk of a short circuit. This is advantageous because this portion of the second planar electrode is directly adjacent to the connection region (where the first planar electrode is exposed and the collector rail extends therein), so that there is a risk that this portion of the second planar electrode will come into contact with the first planar electrode, the collector rail of the first planar electrode, or their electrical contacts and cause a short circuit.

[0027] The at least one insulating line for insulating the second planar electrode region adjacent to the connection region has a width (line width) of, for example, 5 μm to 500 μm, in particular 20 μm to 200 μm and is preferably introduced into the second planar electrode by laser irradiation.

[0028] If the connection region adjoins a lateral edge of the functional element, a single insulating line is sufficient, which divides the second planar electrode into an active region and an electrically insulating region adjoining the connection region. If the connection region does not adjoin a lateral edge of the functional element, two insulating lines are used, which divide the second planar electrode into two active regions and two electrically insulating regions, each adjoining the connection region on one side.

[0029] In one embodiment of the invention, the second planar electrode (or each active area thereof, if the second planar electrode is divided into two parts by a connection area that is not adjacent to the lateral edges of the functional element and / or the second planar electrode area adjacent to the connection area is insulated from the at least one active area in at least one intermediate area by at least one insulating line) is formed as a continuous, uninterrupted layer. It is not divided into several electrically insulating segments (segments) by insulating lines. The functional element (or its active area) can then be brought into a uniform optical state by an applied voltage; there are no independently controllable switching areas. The second planar electrode is preferably conductively connected to a single collecting rail in the second contact area. If the second planar electrode is divided into two parts by a connection area that is not adjacent to the lateral edges of the functional element, each part is preferably conductively connected to a single collecting rail. The second planar electrode and the first planar electrode are electrically connected to a voltage source, so that a voltage can be applied between the second planar electrode on the one hand and the first planar electrode on the other hand in order to control the optical properties of the active layer / layer sequence located therebetween.

[0030] In another embodiment of the invention, the second planar electrode (or at least one, preferably each active area thereof, if the second planar electrode is divided into two parts by a connection area which is not adjacent to the lateral edge of the functional element and / or the area of ​​the second planar electrode adjacent to the connection area is insulated from the at least one active area by at least one insulating line in at least one intermediate area) is divided into at least two separate electrode segments by at least one insulating line. Each electrode segment is conductively connected to a (separate or separate) current collecting rail. Each electrode segment of the second planar electrode and the first planar electrode (or its active area) are electrically connected to a voltage source, so that a voltage can be applied independently between each electrode segment of the second planar electrode and the first planar electrode (or its active area) in order to control the optical properties of the part of the active layer / layer sequence located between them. In this way, several independent switching areas can be realized, the optical properties of which can be electrically controlled independently of each other.

[0031] Therefore, in this embodiment, the second planar electrode has at least two segments (electrode segments) separated from each other by insulating lines. The second planar electrode can be subdivided into several segments by several insulating lines. Each electrode segment forms a switching region of the composite glass pane. The number of electrode segments can be freely selected by a person skilled in the art as required on an individual basis. In a preferred embodiment, the insulating lines extend substantially parallel to each other and from one lateral edge of the planar electrode to the opposite lateral edge. However, any other geometric shapes are also conceivable.

[0032] The insulating lines between the segments of the second planar electrode have a width of, for example, 5 μm to 500 μm, particularly 20 μm to 200 μm. They are preferably introduced into the second planar electrode by laser irradiation. The segment width, i.e., the distance between adjacent insulating lines, can be appropriately selected by a person skilled in the art based on the requirements of the individual case.

[0033] The electrode segments of the second planar electrode are electrically connected to a voltage source independently of one another, so that a second potential (constant over time in the case of a direct voltage, varying 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 a switching potential. The first planar electrode (or its active area) is also electrically connected to a voltage source, so that a first potential (which can also be referred to as a reference potential ("ground") can be applied to the first planar electrode (or its active area) as a whole. If the first and second potentials are identical, no voltage will exist between the electrodes in the respective switching areas (0% switching state). If the first and second potentials are different, a voltage is applied between the electrodes in the respective switching areas, resulting in 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 planar electrode is preferably formed as a continuous, uninterrupted layer. Thus, the first planar electrode has no insulating lines that would divide it into separate segments. A uniform potential is preferably applied to the first planar electrode.

[0035] An insulated line is understood to mean a line or linear region in which the material of the planar electrode is absent, so that adjacent parts (segments) are substantially separated from one another and are therefore electrically insulated from one another. This means that there is no direct electrical connection between the parts (segments), but that the parts (segments) may be indirectly connected to one another in a conductive manner to a certain extent via the active layer in contact therewith.

[0036] The collecting rails are used to distribute the electrical contact of the corresponding planar electrodes with the voltage source over a relatively large contact area and to introduce or release current over the maximum possible width. They are also referred to as "busbars". The collecting rails preferably have a thickness of 2 mm to 20 mm, particularly preferably 4 mm to 9 mm. The width of the collecting rails is preferably less than the width of the contact area and the connection area, for example, about 1 mm. The collecting rails are preferably formed by conductive foil (particularly as a strip or portion of conductive foil). The foil is particularly preferably a metal foil, in particular a copper foil. The copper foil can be tinned. The metal foil, for example, has a thickness of 0.02 mm to 0.2 mm, preferably 0.05 mm to 0.1 mm. However, a polymer carrier film provided with a conductive coating (for example a silver coating) can also be used.

[0037] The collecting rails can be formed independently of each other in one piece (i.e. a single strip or part from a conductive foil) or in multiple pieces (i.e. several combined strips or parts from a conductive foil). In a preferred embodiment, the collecting rails of the second planar electrode are formed in one piece (in particular as a strip of conductive foil) and the collecting rails of the first planar electrode are formed in one piece or in multiple pieces. In the case of a multi-piece design, the two parts of the collecting rails on the contact area and the connection area are preferably each formed in one piece and connected to each other, for example superimposed on each other, welded or bonded in a conductive manner. The collecting rails of the first planar electrode typically have an L-like shape (when the connecting part is adjacent to the lateral edge of the functional element) or a T-like shape (when the connecting part is not adjacent to the lateral edge of the functional element). In the one-piece design, a T-shaped or L-shaped part of the conductive foil can be used, or the strip of conductive foil can be folded into a T-like or L-like shape.

[0038] The current collecting rails are electrically conductively connected to the associated planar electrodes. The current collecting rails can, for example, be simply placed on the planar electrodes, soldered to the planar electrodes, or connected to the planar electrodes via a conductive adhesive. In advantageous embodiments, an electrical contact layer is arranged between the planar electrodes and the current collecting rails to improve the electrical contact. The contact layer can be formed, for example, as a silver-containing paste having a thickness of 0.01 mm to 0.2 mm, preferably 0.02 mm to 0.1 mm, and in particular 0.02 mm to 0.05 mm.

[0039] Electrical conductors are connected to the current collecting rails of the first planar electrode and the second planar electrode, or to the current collecting rails of various segments of the second planar electrode, and extend beyond the lateral edges of the composite glass pane for connection to an external voltage source. The conductors can be manufactured in one piece or in multiple pieces. The conductors can be, for example, metal wires, metal foils, and / or cables that extend from the respective planar electrodes beyond the lateral edges of the composite glass pane.

[0040] In a preferred development of the present invention, the conductor comprises a strip conductor that extends beyond the lateral edge of the composite glass pane, and the collecting rails of the planar electrodes are connected to the strip conductor via an electrical conductor. The composite glass pane then comprises a strip conductor. The strip conductor is arranged laterally at a distance from the functional element, in particular on the side having the second contact area where the electrical connection is made, and extends beyond the lateral edge of the composite glass pane. The collecting rails of the first planar electrode and at least one collecting rail of the second planar electrode are connected to the strip conductor via an electrical conductor. The strip conductor advantageously facilitates the electrical connection of the functional element. In particular, it eliminates the need to lay multiple separate cables for each individual collecting rail.

[0041] The strip conductor has a plurality of conductive tracks, in particular each conductive track is formed by a strip of metal foil (e.g. copper foil). Preferably, all conductive tracks are connected via a polymer sheath or a carrier layer to form a component. The first planar electrode is assigned a conductive track and is connected to the track via an electrical conductor. The second planar electrode

[0042] - allocating a conductive track to which the second planar electrode is connected via an electrical conductor, or

[0043] - several conductive tracks are allocated, wherein each segment of the second planar electrode is connected to a (separate) track via an electrical conductor, so that each electrode segment is connected to exactly one track, and each track is connected to exactly one electrode segment. The strip conductor 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").

[0044] In a preferred embodiment of the present invention, an electrical contact element is connected to each collecting rail. In other words, the collecting rails are each equipped with an electrical contact element, wherein the contact element is, for example, placed on the collecting rail, welded to the collecting rail or bonded with a conductive adhesive. The electrical contact element is preferably formed by a conductive foil, in particular a copper foil. The copper foil can be tin-plated. The thickness of the metal foil is, for example, 0.02 mm to 0.2 mm, preferably 0.05 mm to 0.1 mm. Alternatively, the contact element can be designed as a carrier film, for example, with a conductive coating (for example, a silver coating). The contact element preferably has at least one portion that extends from the collecting rail beyond the lateral edge of the functional element, in particular substantially perpendicular to the running direction of the collecting rail. The portion is preferably connected to a strip conductor. The contact element can, for example, have a strip-like or T-like shape.

[0045] The contact element can be directly connected to the strip conductor. Alternatively, the contact element can be indirectly connected to the strip conductor via an electrical line. The electrical line is preferably a metal wire, a cable or a printed line.

[0046] The contact element can also be used in cases where the electrical lines themselves extend beyond the lateral edges of the composite glass pane, ie there is no common strip conductor.

[0047] Electrically controlled functional elements are multilayer or functional films in which the actual active layer or layer sequence and the planar electrodes are located between two carrier films. Such multilayer films can be purchased commercially, cut to size and shape, and then laminated into composite glass panes, where they are preferably connected to the outer and inner glass panes via corresponding thermoplastic connecting layers.

[0048] The first and second carrier films are formed, for example, based on polyethylene terephthalate (PET), polypropylene, polyvinyl chloride, fluorinated ethylene propylene, polyvinyl fluoride or ethylene tetrafluoroethylene, preferably based on PET. The thickness of the carrier films is preferably 10 μm to 200 μm.

[0049] The lateral edges of the functional element can be sealed, for example by fusing the carrier layer or by means of a (preferably polymer) adhesive tape or polymer film. This protects the active layer, in particular preventing components of the intermediate layer (in particular the plasticizer) from diffusing into the active layer, which could lead to degradation of the functional element.

[0050] The first and second planar electrodes are preferably transparent, which in the context of the present invention means that they have a light transmission of at least 50%, preferably at least 70%, and particularly preferably at least 80% in the visible spectral range. The planar electrodes preferably contain at least one metal, metal alloy, or transparent conductive oxide (TCO). The planar electrodes can be based, for example, on 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 on silver or ITO. The planar electrodes preferably have a thickness of 10 nm to 2 μm, particularly preferably 20 nm to 1 μm, and very particularly preferably 30 nm to 500 nm.

[0051] The active layer or layer sequence has variable optical properties that can be controlled by a voltage applied to the active layer via planar electrodes. In the context of the present invention, electrically controllable optical properties are understood to mean such continuously controllable properties. However, in principle, it is also conceivable that the electrically controllable optical properties can be switched only between two discrete states (or also between more than two discrete states). The optical properties concern, in particular, light transmission and / or scattering behavior.

[0052] Depending on the type of functional element, there may be a single active layer or a sequence of active layers (i.e. a plurality of different layers which together provide variable optical properties). Various types of functional elements can be used, wherein in a preferred embodiment the functional element is a functional element based on liquid crystal technology (in particular a PDLC functional element), an SPD functional element or an electrochromic functional element.

[0053] 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 planar electrodes, which is the basis for the electrical control of optical properties. In particular, the following functional elements based on liquid crystal technology are common:

[0054] PDLC (Polymer Dispersed Liquid Crystal) functional element: The active layer consists of liquid crystal droplets in a polymer matrix. If the liquid crystal is aligned in an electric field, it is transparent and non-light-scattering; if the liquid crystal is not aligned in the absence of an electric field, it is translucent and strongly light-scattering.

[0055] PNLC (Polymer Network Liquid Crystal) functional element: The active layer contains liquid crystals embedded in a polymer network. When no voltage is applied, the liquid crystals are aligned and transparent and non-light-scattering. When voltage is applied, a configurational change occurs, resulting in strong scattering in the liquid crystals, making the state translucent and highly light-scattering.

[0056] -Guest-host functional element: The active layer contains dichroic dye molecules (guest) dissolved in liquid crystals (host). The liquid crystals align in an electric field, thus affecting the orientation of the dye molecules, which results in a changed transmission level (tinting level) and a changed color.

[0057] An SPD (Suspended Particle Device) functional element has an active layer containing suspended particles. The light absorption of the active layer can be changed by applying a voltage to planar electrodes, which causes the orientation of the suspended particles to change.

[0058] The electrochromic functional element comprises an active layer sequence (electrochromic layer sequence) between planar electrodes, which is arranged in the following order: ion storage layer, electrolyte layer and electrochromic layer. 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 storage. Ions (e.g. H + -Li + 、Na + - or K + - ions) are stored in and provided by the ion storage layer. The electrolyte layer spatially separates the electrochromic layer from the ion storage layer and is used to migrate ions. If a DC voltage of appropriate polarity is applied to the planar electrodes, ions will migrate from the ion storage layer, pass through the electrolyte layer, and enter the electrochromic layer, whereupon the optical properties (color, light transmittance) of the electrochromic layer change according to the amount of ions that have migrated into the layer. If a DC voltage of opposite polarity is applied to the planar electrodes, ions will migrate from the electrochromic layer, pass through the electrolyte layer and return to the ion storage layer, and the optical properties of the electrochromic layer change in the opposite manner. If no voltage is applied to the planar electrodes, the current state will remain stable. Suitable electrochromic layers contain electrochromic materials, such as 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 designed as a film of an organic or inorganic, electrically insulating material with high ionic conductivity, such as based on lithium phosphorus nitride oxide. The ion storage layer is either permanently transparent (pure ion storage) or has an electrochromic behavior opposite to that of the electrochromic layer. An example of a pure ion storage 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.

[0059] The voltage source for the functional element is preferably a control unit suitable for operating the functional element. The control unit is suitable for applying a voltage between the first planar electrode on the one hand and the second planar electrode or the electrode segment of the second planar electrode on the other hand (respectively). Depending on the type of functional element, the voltage provided by the control unit can be a DC voltage (for example, in the case of an electrochromic functional element) or an AC voltage (for example, in the case of an SPD functional element or a PDLC functional element or other functional elements based on liquid crystal technology). If the main voltage source provides a DC voltage (for example, as is common in the electrical system of a vehicle) and the functional element operates with an AC voltage, the control unit may include an inverter. If the main voltage source provides an AC voltage when the functional element operates with a DC voltage, the control unit may include a rectifier.

[0060] A control unit is provided and adapted to control the optical properties of the functional element. The control unit is electrically conductively connected to the planar electrodes of the functional element on the one hand and to a mains voltage source on the other. The control unit contains the electrical and / or electronic components required to apply the desired voltage (depending on the switching state) to the planar electrodes. The switching state can be predefined by the user (e.g., by operating a switch, button, or rotary or sliding controller), determined by a sensor, and / or transmitted from a central control unit of the vehicle via a digital interface (typically a LIN bus or CAN bus if the composite glass pane is a vehicle window pane). If the composite glass pane is a vehicle window pane, the switch, button, rotary or sliding controller can, for example, be integrated into the vehicle's dashboard. However, touch sensors, such as capacitive or resistive sensors, can also be integrated directly into the composite glass pane. Alternatively, the functional element can be controlled via contactless methods, such as by gesture recognition or based on the pupil or eyelid state determined by a camera and suitable evaluation electronics. The control unit can, for example, include an electronic processor, a voltage converter, transistors, and other components.

[0061] The control unit may be attached to the inner surface of the inner glazing facing away from the interlayer, or for example integrated into the electrical system of the vehicle or, if the composite glazing is a vehicle window pane, to the vehicle body.

[0062] Composite glass panels are generally provided for separating an interior space from the exterior environment in window openings (e.g., window openings of vehicles, buildings, or rooms). In the context of the present invention, the term "inner glass panel" is understood to mean the glass panel facing the interior space. The outer glass panel refers to the glass panel facing the exterior environment. The outer glass panel and the inner glass panel each have an outer surface and an inner surface and a circumferential lateral edge surface extending between them. Within the meaning of the present invention, the outer surface refers to the main surface intended to face the exterior environment when installed. Within the meaning of the present invention, the inner surface refers to the main surface intended to face the interior when installed. The inner surface of the outer glass panel and the outer surface of the inner glass panel face each other and are bonded to each other by a thermoplastic interlayer.

[0063] The outer and inner glass panes are preferably made of or formed from glass, particularly preferably from soda-lime glass, as is customary for window panes. However, the glass panes can also be made from other types of glass, such as quartz glass, borosilicate glass, or aluminosilicate glass, or from rigid transparent plastic, such as polycarbonate or polymethyl methacrylate. The glass panes can be transparent or tinted or colored.

[0064] The thickness of the outer and inner glass panes can vary widely and thus be adapted to the requirements of the individual case. The outer and inner glass panes preferably have a thickness of 0.5 mm to 5 mm, particularly preferably 1 mm to 3 mm. The outer and inner glass panes can be flat or cylindrically or spherically curved. Spherically curved composite glass panes are particularly common for vehicle glazing, while flat composite glass panes are common for building glazing.

[0065] The outer glass pane, the inner glass pane and / or the intermediate layer can have suitable coatings known per se, such as antireflective coatings, non-stick coatings, anti-scratch coatings, photocatalytic coatings, UV-absorbing or reflecting coatings or IR-absorbing or reflecting coatings, such as sun protection coatings or low-E coatings.

[0066] Composite glass panes can be provided with an opaque cover print, in particular at least in the surrounding edge region, as is common practice in the vehicle sector, in particular for windshields, rear windows and roof panes. The cover print is usually made of an enamel containing glass frit and a pigment, in particular a black pigment. The printing ink is usually applied by screen printing and then burned in. This cover print is applied to at least one of the glass pane surfaces, preferably the inner surface of the outer glass pane and / or the inner glass pane. The cover print preferably surrounds the central perspective area in a frame-like manner. The cover print creates an opaque shielding area on the composite glass pane. The contact areas and connection areas of the functional elements are preferably arranged in this shielding area.

[0067] Thermoplastic interlayers are commonly used to connect two glass panes, as is common in composite glass panes. A thermoplastic film is typically used, and this interlayer forms the interlayer. In a preferred embodiment, the functional element is arranged between the two thermoplastic layers. The interlayer is formed by at least a first thermoplastic layer and a second thermoplastic layer, with the functional element arranged between them. The functional element is then connected to the outer glass pane via the region of the first thermoplastic layer and to the inner glass pane via the region of the second thermoplastic layer. The thermoplastic layer preferably protrudes all the way beyond the functional element. If the thermoplastic layers are in direct contact with one another and are not separated by the functional element, they can fuse together during lamination in such a way that the original layers are no longer discernible, and a homogeneous interlayer is instead present.

[0068] The thermoplastic layer may, for example, be formed from a single thermoplastic film.The thermoplastic layer may also be formed from portions of different thermoplastic films, the lateral edges of which are attached to each other.

[0069] In a preferred embodiment, the functional element, or more precisely the lateral edge of the functional element, is surrounded by a third thermoplastic layer. The third thermoplastic layer is frame-shaped with a groove into which the functional element is inserted. The third thermoplastic layer can be formed by a thermoplastic film into which the groove has been introduced by cutting. Alternatively, the third thermoplastic layer can also be composed of multiple film portions surrounding the functional element. The intermediate layer is then formed by a total of at least three thermoplastic layers arranged flat on top of each other, wherein the intermediate layer has a groove in which the functional element is arranged. During production, the third thermoplastic layer is arranged between the first and second thermoplastic layers, wherein the lateral edges of all thermoplastic layers are preferably congruent. The third thermoplastic layer preferably has approximately the same thickness as the functional element. This compensates for local thickness differences introduced by locally limited functional elements, making it possible to avoid glass breakage during lamination and produce an improved visual appearance.

[0070] Alternatively, however, the functional element can also be arranged directly on the surface of the outer or inner glass pane facing the intermediate layer. Preferably, the side edges of the functional element are completely surrounded by the intermediate layer, so that the functional element does not extend all the way to the side edges of the composite glass pane and is therefore not in contact with the ambient atmosphere. Here, it is also possible to use a frame-like thermoplastic layer surrounding the functional element.

[0071] The thermoplastic layers of the intermediate layer are preferably formed from the same material, but in principle can also be formed from 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 primarily contains the aforementioned material (more than 50% by weight) and may optionally contain other components, such as plasticizers, stabilizers, and UV or IR absorbers. The thickness of each thermoplastic layer is preferably 0.2 mm to 2 mm, particularly preferably 0.3 mm to 1 mm. For example, films with a standard thickness of 0.38 mm or 0.76 mm can be used.

[0072] Composite glass panes can be produced by stacking the individual layers in the desired order to form a layer stack and then laminating the outer and inner glass panes together via an intermediate layer. Methods known per se can be used, such as the autoclave method, the vacuum bag method, the vacuum ring method, the calendaring method, a vacuum laminator, or a combination thereof. The outer and inner glass panes are typically joined under the action of heat, vacuum, and / or pressure.

[0073] The layer stack preferably contains, in the order specified:

[0074] -Outer glass panel

[0075] - a first thermoplastic film forming the first thermoplastic layer of the intermediate layer,

[0076] - a functional element, preferably encapsulated in a frame-shaped third thermoplastic film having grooves,

[0077] - a second thermoplastic film forming the second thermoplastic layer of the intermediate layer,

[0078] -Inner glass pane.

[0079] When the layers are stacked, the functional elements are provided with the required electrical connections, wherein the electrical conductors extend beyond the lateral edges of the layer stack, to which an external voltage source can later be supplied.

[0080] In an advantageous embodiment, the functional element is provided with a collector rail, which is optionally connected to the planar electrode via an electrical contact layer. The electrical conductor is arranged on the thermoplastic film and appropriately positioned so that when the layer stack is formed, the electrical conductor is in contact with the collector rail without any further measures. The electrical conductor preferably comprises a strip conductor arranged laterally to the functional element, an electrical contact element for direct connection to the collector rail, and an electrical line (in particular a wire or cable) between each contact element and the conductor track of the strip conductor. The electrical conductors are each attached to a thermoplastic film, to which the planar electrode to be in contact with the conductor is exposed. For example, if the first carrier film and the first planar electrode face the first thermoplastic film, the first planar electrode is exposed to the second thermoplastic film in the first contact area: in the first contact area, only the first carrier film and the first planar electrode are present, wherein the first planar electrode faces the second thermoplastic layer.

[0081] The present invention also encompasses the use of a composite glass pane according to the invention in buildings or in vehicles for land, air, or water transportation, for example as a window pane for a vehicle, as a window pane for a building or room (building interior), or as a component of furniture, electrical appliances, or household items. The composite glass pane is preferably a window pane for a vehicle, in particular a motor vehicle. The glazing unit can be used, for example, as a windshield, roof pane, rear pane, or side pane, preferably as a windshield or roof pane.

[0082] In a particularly preferred embodiment, the composite glass pane is a vehicle windshield. The functional element, which preferably serves as an electrically controlled sunshade, is arranged in the upper region of the windshield, while the majority of the windshield is free of the functional element. Multiple switch zones can be provided, preferably arranged substantially parallel to the upper edge of the windshield at increasing distances therefrom. The independently switchable switch zones allow the user to determine the extent of the area adjacent to the upper edge to be shaded or to provide a high light-scattering function, depending on the sun's position, in order to prevent sun glare.

[0083] In another preferred embodiment, the composite glass pane is the roof pane of a vehicle. The functional element is then preferably arranged within the entire perspective area of ​​the composite glass pane. In a typical embodiment, this perspective area encompasses the entire composite glass pane minus a surrounding edge region, which is provided with an opaque overprint on at least one surface of the glass pane. The functional element extends across the entire perspective area, with its lateral edges arranged within the region of the opaque overprint and therefore invisible to the observer. The switch area is preferably arranged substantially parallel to the front edge of the roof pane, with a gradually increasing distance therefrom. With the help of independently switchable switch areas, the user can define which areas of the roof pane should be transparent and which areas should be shaded or have high light scattering, for example, based on the position of the sun to prevent overheating of the vehicle interior. It is also possible to assign a switch area above each vehicle passenger (e.g., the driver, the front passenger, the passenger in the left rear seat, and the passenger in the right rear seat).

[0084] The invention is explained in more detail with reference to the accompanying drawings and exemplary embodiments. The drawings are schematic representations and are not true to scale. The drawings do not limit the invention in any way. In the drawings:

[0085] Figure 1 is a cross-section of an embodiment of a composite glass pane according to the invention,

[0086] Figure 2 Is from Figure 1 Cross-section of a functional element of a composite glass pane,

[0087] Figure 3 Is from Figure 2 A floor plan of the functional elements,

[0088] Figure 4 is a plan view of a functional element of another embodiment of a composite glass pane according to the invention,

[0089] Figure 5 is a plan view of a functional element of another embodiment of a composite glass pane according to the invention, and

[0090] Figure 6 It is a plan view of the functional elements of a conventional general composite glass panel.

[0091] Figure 1A cross-section of a design of a composite glass pane with electrically controllable optical properties according to the present invention is shown. For example, the composite glass pane is provided as a roof pane for a passenger vehicle, the light transmission of which can be electrically controlled. The composite glass pane comprises an outer glass pane 1 and an inner glass pane 2, which are connected to each other via an interlayer 3. The outer glass pane 1 and the inner glass pane 2 are composed of soda-lime glass, which may optionally be tinted. The outer glass pane 1 has a thickness of, for example, 2.1 mm, and the inner glass pane 2 has a thickness of 1.6 mm.

[0092] The intermediate layer 3 comprises a total of three thermoplastic layers 3a, 3b, and 3c, each formed from a 0.38 mm thick PVB thermoplastic film. The first thermoplastic layer 3a is bonded to the outer glass pane 1, and the second thermoplastic layer 3b is bonded to the inner glass pane 2. The third thermoplastic layer 3c, situated therebetween, has a cutout into which the functional element 10 with electrically controllable optical properties is inserted, with a substantially exact fit (i.e., approximately flush in all directions). The third thermoplastic layer 3c thus forms a kind of mount or frame for the approximately 0.4 mm thick functional element 10, which is thus encapsulated and protected by the thermoplastic material.

[0093] The composite glass pane has a surrounding edge region provided with an opaque cover print 4. This cover print 4 is typically formed from black enamel. It is screen-printed using a printing ink containing black pigment and glass frit and burned into the glass pane surface. The cover print 4 is applied, for example, to the inside surface of the outer glass pane 1 and also to the inside surface of the inner glass pane 2. The lateral edges of the functional element 10 are covered by this cover print 4.

[0094] For clarity, Figure 2 Shown separately from Figure 1 1. A cross-section of a functional element 10. The functional element 10 is, for example, a PDLC multilayer film, which can be switched from a clear, transparent state to an opaque, non-transparent (diffuse) state. The functional element 10 consists of an active layer 11 between a first planar electrode 14 and a second planar electrode 15. The first planar electrode 14 is applied to a first carrier film 12 and the second planar electrode 15 is applied to a second carrier film 13. The active layer 11 comprises a polymer matrix in which liquid crystals are dispersed, which are arranged depending on the voltage applied to the planar electrodes 14, 15, so that 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 films 12, 13 are each provided with an ITO coating facing the active layer 11 and having a thickness of approximately 100 nm, said coating forming the planar electrodes 14, 15.

[0095] Functional element 10 has a first contact region in which first planar electrode 14 is exposed for connection to a voltage source. In this first contact region, second carrier film 13, second planar electrode 15, and active layer 11 are removed. In this first contact region, current collecting rail 21 is arranged on first planar electrode 14 via electrical contact layer 23.

[0096] Functional element 10 has a second contact region in which second planar electrode 15 is exposed for connection to a voltage source. In this second contact region, first carrier film 12, first planar electrode 14, and active layer 11 are removed. In this second contact region, current collecting rail 22 is arranged on second planar electrode 15 via electrical contact layer 23.

[0097] Figure 3 Shown from Figure 2 1. A plan view of the functional element 10. The second carrier film 13 faces the viewer. The functional element has a rectangular shape with four straight sides and four corners.

[0098] The first contact region extends along the left portion and directly adjoins the lateral edge of the functional element 10. There, the second carrier film 13 together with the second planar electrode 15 and the active layer 11 are removed so that the exposed first planar electrode 14 (shown in dashed lines) on the first carrier layer 12 can be seen.

[0099] The second contact region extends along the right section and directly adjoins the lateral edge of the functional element 10. There, the first carrier film 12 is removed along with the first planar electrode 14 and the active layer 11. The second planar electrode 15 is not visible here because it is covered by the second carrier film 13 on top. The left boundary (cut line) of the second contact region is indicated by a thin dashed line.

[0100] The collecting rail 22 is arranged on the second planar electrode 15 in the second contact region. It is shown in dashed outline and grey because it is located behind the second carrier film 13 and is therefore only visible when looking through it. In the first contact region, the collecting rail 21 is arranged on the first planar electrode 14.

[0101] Adjacent to the lower edge, the connection region extends from the first contact region to the opposite right part of the functional element 10. In the connection region, just as in the first contact region, the second carrier film 13, the second planar electrode 15 and the active layer 11 are removed so that the first planar electrode 14 is exposed.

[0102] A portion of the current collecting rail 21 of the first planar electrode 14 is arranged in the first contact region. Another portion is arranged in a connection region starting from the first contact region to the opposite right-hand portion of the functional element 10. This has the advantage that both current collecting rails 21, 22 can be electrically connected to the same side of the functional element 10, i.e., the right-hand portion.

[0103] The dashed outline of the second contact region corresponds to the cutting line used to remove the first carrier film 12. In the plan view shown, this line is located below the second contact region to the right of the lateral edge of the functional element before reaching the connection region. Therefore, an intermediate region is arranged between the second contact region and the connection region, in which the first carrier film 12, the first planar electrode 14, and the active layer 11 are not removed.

[0104] For electrical connection to an external voltage source, the composite glass pane is equipped with a strip conductor 27, which is arranged laterally of the functional element 10, spaced apart from the right portion. The strip conductor 27 extends beyond the lateral edge of the composite glass pane. A T-shaped electrical contact element 25 is arranged on the collecting rail 22 of the second planar electrode 15 and directly connected to the strip conductor 27. The majority of the contact element 25 is again shown with a dashed outline and in gray, as it is located behind the second carrier film 13 and the collecting rail 22. On the collecting rail 21 of the first planar electrode 14, a strip-like electrical contact element 24 is arranged in the connection area and directly connected to the strip conductor 27. Each contact element 24, 25 is connected to one of the two conductor tracks of the strip conductor 27, which are not shown for simplicity.

[0105] The collecting rails have a width of, for example, 5 mm. They are made of copper foil, for example, 50 μm thick. The electrical contact layer 23 consists, for example, of silver paste, 50 μm thick. The electrical contact elements 24 , 25 are also formed, for example, of copper foil, for example, 50 μm thick.

[0106] In the intermediate region between the second contact region and the connection region, a portion of the second planar electrode 15 is electrically insulated from the remainder of the second planar electrode 15 by an insulating line 16. The insulating line 16 divides the second planar electrode 15 into an active region, which serves as the actual planar electrode, and a region adjacent to the connection region, which is insulated therefrom. This reduces the risk of short circuits, as the portion of the second planar electrode 15 adjacent to the connection region can easily contact the first planar electrode 14 or its current collecting rail 21. The insulating line 16 is introduced into the second planar electrode 15 by laser irradiation and has a line width of, for example, 100 μm.

[0107] Figure 4 FIG. 1 shows a plan view of a functional element 10 in another embodiment of a composite glass pane according to the invention. Figure 2 and 3 The embodiment shown is constructed in the same manner. In contrast, the functional element 10 has three independent switching areas, the switching states of which can be set independently of one another. Using the switching areas, the vehicle driver can choose (e.g., depending on the position of the sun) to provide only one area of ​​the composite glass pane with a diffuse state, rather than the entire composite glass pane, while the other areas remain transparent.

[0108] For this purpose, the second planar electrode 15 is divided into three electrode segments 15.1, 15.2, and 15.3 by two insulating lines 15'. The insulating lines 15' are introduced into the planar electrode 15 by laser radiation and have a line width of, for example, 100 μm. Each electrode segment 15.1, 15.2, and 15.3 is connected to a voltage source independently of the others. The control unit is adapted to apply voltages independently of one another between each electrode segment 15.1, 15.2, and 15.3 of the first planar electrode 15, on the one hand, and the first planar electrode 14, on the other hand, so that the portion of the active layer 11 located therebetween is subjected to the desired voltage to achieve the desired switching state.

[0109] Each electrode segment 15.1, 15.2, 15.3 is provided with a collecting rail 22.1, 22.2, 22.3 in the second contact region, which collecting rails are in turn provided with electrical contact elements 25.1, 25.2, 25.3. Figure 2 and 3 In contrast to the design of the contact elements 24, 25.1, 25.2, 25.3, the contact elements 24, 25.1, 25.2, 25.3 are not connected directly to the strip conductor 27, but rather via an electrical line 26 connected thereto. The strip conductor 27 has at least four conductor tracks, wherein each collecting rail 21, 22.1, 22.2, 22.3 is connected to a separate conductor track. The electrical line 26 is formed as a tungsten wire, for example, with a diameter of 150 μm.

[0110] and Figure 2 and 3 Another difference in the design of the second contact area is the shape of the dotted outline. This does not form a right angle below the second contact area so that it can be guided to the right part. Instead, it describes a curve that is technically easier to realize.

[0111] In the present embodiment, too, in the intermediate region between the second contact region and the connection region, a portion of the second planar electrode 15 is electrically insulated from the remaining second planar electrode 15 by an insulating wire 16. The insulating wire 16 divides the second planar electrode 15 into an active region (which serves as the actual planar electrode and is divided into three independent segments 15.1, 15.2, 15.3) and an area insulated therefrom (which adjoins the connection region). This reduces the risk of short circuits, since the portion of the second planar electrode 15 adjacent to the connection region can easily contact the first planar electrode 14 or its current collecting rail 21. The insulating wire 16 is introduced into the second planar electrode 15 by laser radiation and has a line width of, for example, 100 μm. Since the functional element 10 has already undergone a laser process to produce the insulating wire 15', the production of the insulating wire 16 requires only a small amount of additional expenditure.

[0112] Figure 5FIG. 1 shows a plan view of a functional element 10 in another embodiment of a composite glass pane according to the invention. Figure 2 and 3 The embodiment shown is constructed in the same manner. In contrast, the connection region is not arranged adjacent to the underside part, but rather in the central region of the functional element 10 .

[0113] Since the second carrier film 13, together with the second planar electrode 15 and the active layer 11, is 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. In the switching region, the carrier film 12, the carrier film 13, the planar electrodes 14, 15, and the active layer 11 are completely present. The second planar electrode 15 is divided into two electrode segments 15.1, 15.2 by the connection region. The second contact region is also divided into two parts. Each electrode segment 15.1, 15.2 is arranged in the second contact region having a collecting rail 22.1, 22.2, which is connected to a strip conductor 27 in turn via electrical contact elements 25.1, 25.2 and electrical lines 26 connected thereto. The strip conductor 27 has at least three conductor tracks, wherein each collecting rail 21, 22.1, 22.2 is connected to a separate conductor track.

[0114] Between each portion of the second contact region and the connection region, an intermediate region is again arranged in the plan view shown, in which the first carrier film 12, the first planar electrode 14 and the active layer 11 are not removed. In each intermediate region, an insulating line 16 is arranged, which divides the corresponding portion of the second planar electrode 15 into an active portion and a portion (adjacent to the connection region) insulated from the active portion, which serves to avoid short circuits in the connection region.

[0115] For comparison, Figure 6 FIG. 1 shows a plan view of a functional element 10 in a conventional design of a universal composite glass pane. Figure 4 As shown, the functional element 10 is divided into three independent switching areas.

[0116] The electrical connections are made via electrical lines 26, which extend from the respective collecting rails beyond the lateral edges of the composite glass pane. The connection to the collecting rails 21 of the first planar electrode 14 is made on the left side of the functional element 10, while the connection to the collecting rails 22.1, 22.2, and 22.3 is made on the right side of the functional element 10. However, since the lines 26 are intended to exit the composite glass pane at approximately the same location, as they are typically combined with a common connector to connect them to a voltage source, the lines 26 of the collecting rails 21 are routed around the functional element 10. Consequently, longer cables 26 are required than in the embodiment according to the present invention, and their installation requires more time.

[0117] List of reference numerals:

[0118] (1) Outer glass panel

[0119] (2) Inner glass panel

[0120] (3) Thermoplastic intermediate layer

[0121] (3a) First layer of the intermediate layer 3

[0122] (3b) Second layer of intermediate layer 3

[0123] (3c) The third layer of the intermediate layer 3

[0124] (4) Covering printed matter

[0125] (10) Electrically controllable functional components

[0126] (11) Active layer of a 4-layer sequence of functional elements with electrically controllable optical properties

[0127] (12) First carrier film of functional element 4

[0128] (13) Second carrier film of functional element 4

[0129] (14) First planar electrode of functional element 4

[0130] (15) Second planar electrode of functional element 4

[0131] (15.1, 15.2, 15.3) Electrode sections of the second planar electrode 15

[0132] (15') Insulation wire between two electrode segments 15.1, 15.2, 15.3

[0133] (16) Insulated wire

[0134] (21) Current collecting rail of the first planar electrode 14

[0135] (22) Current collecting rail of the second planar electrode 15

[0136] (22.1, 22.2, 22.3) The first, second and third current collecting rails of the second planar electrode 15

[0137] (23) Electrical contact layer

[0138] (24) Electrical contact element of collector rail 21

[0139] (25) Electrical contact element of collector rail 22

[0140] (25.1, 25.2, 25.3) Electrical contact elements of the first, second and third current collecting rails of the second planar electrode 15

[0141] (26) Electrical circuits

[0142] (27) Strip conductor

[0143] X-X' cutting line

Claims

1. A composite glass plate having electrically controllable optical properties, comprising an outer glass pane (1) and an inner glass pane (2), which are connected to one another via a thermoplastic intermediate layer (3), - an electrically controllable functional element (10) embedded in said intermediate layer (3), comprising, in the order specified: - a first carrier film (12), - a first planar electrode (14), - an active layer (11) or a layer sequence having electrically controllable optical properties, - a second planar electrode (15) and - a second carrier film (13), in - in a first contact region, the second carrier film (13), the second planar electrode (15) and the active layer (11) or layer sequence are removed and the first planar electrode (14) is electrically conductively connected to a collecting rail (21), and - in a second contact region, the first carrier film (12), the first planar electrode (14) and the active layer (11) or layer sequence are removed, and the second planar electrode (15) is electrically conductively connected to at least one collecting rail (21; 22.1, 22.2, 22.3), wherein the first contact area and the second contact area are arranged on opposite sides of the functional element (10), wherein the current collecting rail (21) of the first planar electrode (14) extends in a connection region from the first contact region to the opposite side of the functional element (10), wherein the second carrier film (13), the second planar electrode (15) and the active layer (11) or layer sequence are removed in the connection region, It is characterized by: An intermediate region is present between the second contact region and the connection region, wherein the first carrier film (12), the first planar electrode (14) and the active layer (11) or layer sequence are not removed, and wherein in the intermediate region the part of the second planar electrode (15) adjoining the connection region is electrically insulated from the remaining second planar electrode (15) by an insulating line (16).

2. The composite glass pane according to claim 1, wherein the current collecting rails (21) of the first planar electrode (14) and at least one current collecting rail (21; 22.1, 22.2, 22.3) are connected to a voltage source via electrical conductors (24, 25, 26, 27), and wherein the electrical conductors (24, 25, 26, 27) are connected to the collecting rails (21) of the first planar electrode (14) and at least one collecting rail (21) of the second planar electrode (15) on the same side of the functional element (10); 22.1、22.2、22.3)。 3. The composite glass pane according to claim 1 , wherein the second planar electrode ( 15 ) is divided into at least two separate electrode segments ( 15 . 1 , 15 . 2 , 15 . 3 ) by at least one insulating line ( 15 ′), and wherein each electrode segment ( 15 . 1 , 15 . 2 , 15 . 3 ) is electrically conductively connected to a corresponding collecting rail ( 22 . 1 , 22 . 2 , 22 . 3 ).

4. The composite glass pane according to any one of claims 1 to 3, wherein the or each insulating line (16) (15', 16) has a width of 5 μm to 500 μm. 5 . The composite glass pane according to claim 1 , wherein the functional element ( 10 ) has an at least approximately quadrilateral, in particular an at least approximately rectangular, shape.

6. The composite glass pane according to any 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. The composite glass pane according to claim 1, wherein the collecting rails (21, 22, 22.1, 22.2, 22.3) are formed from an electrically conductive foil, in particular a copper foil.

8. The composite glass pane according to claim 1, wherein the planar electrodes (14, 15) are formed on the basis of indium tin oxide (ITO) or silver.

9. The composite glass pane according to claim 1 , comprising a strip conductor ( 27 ) which is arranged laterally of the functional element ( 10 ) and extends beyond the lateral edge of the composite glass pane, wherein the collecting rails ( 21 ) of the first planar electrode ( 14 ) and the at least one collecting rail ( 22 ; 22 . 1 , 22 . 2 , 22 . 3 ) of the second planar electrode ( 15 ) are electrically conductively connected to the strip conductor ( 27 ).

10. The composite glass pane according to claim 9, wherein the collecting rails (21, 22, 22.1, 22.2, 22.3) are each equipped with an electrical contact element (24, 25, 25.1, 25.2, 25.3), which is formed by an electrically conductive foil, in particular a copper foil, and is connected to the strip conductor (27) directly or via corresponding electrical lines (26), wherein the electrical lines (26) are formed as metal wires, cables or printed lines.

11. The composite glass pane according to claim 1, wherein the carrier film (12, 13) is formed on the basis of polyethylene terephthalate (PET) and preferably has a thickness of 10 μm to 200 μm.

12. The composite glass pane according to claim 1 , wherein the functional element ( 10 ) is arranged between two thermoplastic layers ( 3 a, 3 b ), 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. The composite glass pane according to any one of claims 1 to 12, wherein the outer glass pane (1) and the inner glass 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 glass pane according to any one of claims 1 to 13 as a glazing pane for vehicles, in particular as a windshield or roof pane, as a glazing pane for buildings or interior spaces, or as a component of furniture, electrical appliances or household items.

Images