Laminated pane with functional element and segmented bus bar

Abstract

Laminated pane (100) with an electrically controllable functional element (5) which is switchable in segments, the laminated pane (100) at least comprising a first pane (1), a second pane (2), which are joined to one another via an intermediate layer (3), and a functional element (5) that is embedded in the intermediate layer (3), wherein the functional element (5) comprises, flat atop one another in this order: - a first carrier film (14); - a first flat electrode (12), wherein a first bus bar (18) comprising at least two electrically isolated segments (18.1, 18.2) is arranged on the first flat electrode (12) in a first bus bar attachment area (12.5) such that the first bus bar (18) extends from a connection zone (CZ) arranged at a first side edge (5.1) of the functional element (5) towards an opposite third side edge (5.3) of the functional element (5); - an active layer (11); - a second flat electrode (13), wherein a second bus bar (19) is arranged on the second flat electrode (13) in a second bus bar attachment area (13.1); and - a second carrier film (15), wherein the first flat electrode (12) is divided into at least two electrically isolated segments (12.1, 12.2) by at least one separating line (16) extending from the first bus bar attachment area (12.5) towards the second bus bar attachment area (13.1).

Description

[0001] SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0002] 1

[0003] Laminated Pane with Functional Element and Segmented Bus Bar

[0004] The invention relates to a laminated pane with a functional element that can be switched in segments and has electrically controllable optical properties, a method for its production, and its use.

[0005] For protection against dazzling of the driver or other occupants, conventional motor vehicles have mechanical sun visors. These are hinge-mounted on the vehicle roof and can be pivoted downward as needed to prevent or at least to mitigate the dazzling of the driver or front-seat passenger, for example, when the sun is low.

[0006] Also known are windshields into which a sun visor is integrated in the form of a functional element with electrically controllable optical properties, in particular with electrically controllable transmittance or scattering properties. Thus, the driver can control the transmittance behavior of the windshield itself relative to sunlight; the conventional mechanical sun visor can be dispensed with. By this means, the weight of the vehicle can be reduced, and space is gained in the roof region. In addition, electrical control of the sun visor is more convenient for the driver than the manual folding down of the mechanical sun visor.

[0007] Moreover, functional elements with electrically controllable optical properties are also used in sunroofs, side windows, and back windows of motor vehicles. In particular, in the case of large- area panoramic glass panes, there is a need to variably control the transmittance of the pane. Depending on the position of the sun, it is necessary to dim only subregions of the pane, or also to make the entire area non-transparent, for example as a privacy screen in the parked vehicle.

[0008] Laminated panes with controllable transmittance are also used in civil engineering, e.g., office or residential buildings, where they provide dynamic privacy control and enhance energy efficiency by adjusting light transmission. In residential buildings, this so-called “switchable glass” is often installed in bathrooms or bedrooms to allow privacy without obstructing natural light. It is also used in large windows and skylights, where it helps to reduce heat buildup during the day while maintaining views when desired.

[0009] One possible electrically switchable controllable functional element for realizing the controllable sun visor or use in civil engineering is a so-called “PDLC” functional element (polymer dispersed liquid crystal). The active layer contains liquid crystals that are incorporated into a polymer matrix. When no voltage is applied, the liquid crystals are randomly oriented, resulting in strong scattering of the light passing through the active layer. When a voltage is applied to the surface electrodes, SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0010] 2 the liquid crystals align themselves in a common direction and the transmittance of light through the active layer is increased. The PDLC functional element acts less by reducing total transmittance, but rather by increasing scattering to ensure protection against dazzling.

[0011] Windshields with electrically adjustable sun visors are known, for example, from DE 10 2013 001 334 A1 , DE 10 2005 049 081 B3, DE 10 2005 007 427 A1 , US 2021 / 0341772 A1 , and / or DE 10 2007 027 296 A1. DE 10 2010 021 563 A1 describes a windshield with an electrically adjustable sun visor that is switchable in subregions wherein the darkening of the individual elements is controllable via a capacitive sensor arrangement in the edge region of the sun visor.

[0012] The electrical contacting of electrically controllable functional elements is usually done via bus bars that are attached on the surface electrodes in the edge region of the functional element and make electrically conductive contact therewith. More specifically, a first bus bar is attached to a first flat electrode and a second bus bar is attached to a second flat electrode, the first and second electrode being arranged on opposite sides of the active layer. By connecting the bus bars to an external voltage source, for example, via flat conductors attached to the bus bars, a voltage is applied to the surface electrodes and the active layer of the functional element is switched.

[0013] However, especially in the case of small, individually switchable segments, multiple first or second bus bars are required for connecting the segments of the surface electrodes to the voltage source. This, however, also requires multiple wires running from the voltage source to the respective bus bars, thereby increasing the complexity of the wiring necessary for the electrically conductive contact between the voltage source and the bus bars.

[0014] US 2023 / 103913 A1 discloses a functional element having electrically controllable optical properties having a plurality of side edges, at least comprising a stacking sequence consisting of a first carrier film, a first planar electrode that is divided by at least one isolation line into at least two segments, an active layer, a second planar electrode, and a second carrier film, wherein on a first side edge in a first region, the second carrier film, the second planar electrode, and the active layer have a first cutback and in a second region, the first carrier film, the first planar electrode, and the active layer have a second cutback, a group of first bus bars electrically conductively contacts the first planar electrode, and each segment of the first planar electrode is electrically conductively contacted by a bus bar from the group of the first bus bars, at least one second bus bar electrically conductively contacts the second planar electrode, the first bus bars, in a through view, are arranged adjacent one another in a row in the region of the first cutback on the first planar electrode, wherein the first bus bars are electrically separated from one another SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0015] 3 by the at least one isolation line, and the at least one second bus bar, in a through view, is arranged in the region of the second cutback on the second planar electrode.

[0016] The object of the present invention is to provide a laminated pane having a functional element that is switchable in segments with electrically controllable optical properties and that has improved electrical contacting and wiring.

[0017] The object of the present invention is accomplished by a laminated pane having a functional element that is switchable in segments with electrically controllable optical properties according to independent claim 1. Preferred embodiments are apparent from the dependent claims and the entire disclosure.

[0018] The laminated pane according to the invention comprises a functional element which is switchable in segments, the laminated pane at least comprising a first pane, a second pane, which are joined to one another via an intermediate layer, and a functional element that is embedded in the intermediate layer, wherein the functional element comprises, flat atop one another in this order: a first carrier film; a first flat electrode, wherein a first bus bar comprising at least two electrically isolated segments is arranged on the first flat electrode in a first bus bar attachment area such that the first bus bar extends from a connection zone arranged at a first side edge of the functional element towards an opposite third side edge of the functional element; an active layer;

[0019] - a second flat electrode, wherein a second bus bar is arranged on the second flat electrode in a second bus bar attachment area; and a second carrier film, wherein the first flat electrode is divided into at least two electrically isolated segments by at least one separating line extending from the first bus bar attachment area towards the second bus bar attachment area, wherein a first segment of the at least two electrically isolated segments of the first bus bar electrically conductively contacts a first segment of the at least two electrically isolated segments of the first flat electrode, and wherein a second segment of the at least two electrically isolated segments of the first bus bar electrically conductively contacts a second segment of the at least two electrically isolated segments of the first flat electrode.

[0020] According to the invention, the first flat electrode and the first bus bar are each specifically designed and interconnected to achieve the functional element being switchable in segments. SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0021] 4

[0022] The first flat electrode is a layer of material which is divided into at least two electrically isolated segments by at least one separating line extending from the first bus bar attachment area towards the second bus bar attachment area. In other words: the first flat electrode comprises multiple segments, which are each electrically conductive, but are electrically isolated from one another by the at least one separating line. The at least one separating line can be a straight line extending from the first bus bar attachment area to the second bus bar attachment area but can also be a line comprising multiple interconnected straight segments (e.g. having perpendicular and / or zigzag segments), a line with at least one curved segment, or a line with at least one wavy and / or squiggly segment. Irrespective of the actual shape of the separating line, the separating line divides the first flat electrode such that at least two electrically isolated segments are formed. The terms “first bus bar attachment area” and “second bus bar attachment area” refer to respective surface areas of the first or second surface electrode, i.e. , surface areas provided for attachment of the bus bar.

[0023] The first bus bar, however, is segmented and arranged on the first flat electrode such that the segments of the first bus bar electrically conductively contact the segments of the first flat electrode, preferably each segment of the bus bar being electrically conductively contacted with a respective segment of the first flat electrode (see below for details). To achieve this desired connection, the first bus bar extends from the connection zone arranged on the first side edge of the functional element towards the opposite third side edge of the functional element. More specifically, each of the at least two electrically isolated segments of the first bus bar extend, starting from the connection zone arranged at the first side edge of the functional element, towards the opposite third side edge of the functional element. It therefore becomes possible to connect the voltage source to each of the at least two electrically isolated segments of the first bus bar in the connection zone, namely only one specific region of the functional element.

[0024] The inventors have found that connecting each of the electrically isolated segments of the first bus bar in the connection zone reduces the amount of wiring necessary for contacting the electrically isolated segments of the first flat electrode and improves the overall manufacturability of the laminated pane having the functional element. Thereby, the amount of wiring necessary for the contacting of the first flat electrode is reduced, lowering the overall cost of the laminated pane. In addition to this, the contacting of the first flat electrode usually requires only a comparably small amount of silver (compared to copper wire running in parallel to the laminated pane), as the silver paste integrated in the laminated pane has a thickness of only a few micrometers. Furthermore, the complexity of the functional element can be reduced, as the functional element comprises a SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0025] 5 significantly reduced number of areas that require an electrical connection, namely only the connection zone on the first bus bar and a further connection zone on the second bus bar.

[0026] In the context of the invention, the functional element has multiple side edges, preferably four. The functional element can, however, also include more than four side edges. In each case, at least two side edges of the functional element are positioned opposite one another, essentially in pairs. In the case of an embodiment with four side edges, this yields two pairs of two opposite side edges each. The opposite side edges of a functional element can run parallel to one another or nonparallel. The side edges need not be straight, but often have a curve. The length of opposite side edges can differ from one another. For example, the functional element can have a trapezoidal outline.

[0027] The electrically isolated segments of the first bus bar, which electrically contact the respective isolated segments of the first flat electrode, are situated near one another on at least one side edge of the functional element. Preferably, the electrically isolated segments of the first bus bar extend in parallel along the nearest side edge of the functional element. In the context of this invention, the term “extending” is to be understood - with respect to the segments of the first bus bar - as a main extension of the respective segment of the bus bar, i.e., its longest extension in one dimension of a three dimensional space. With respect to the isolated segments of the first bus bar, the term “extending” (e.g. the first segment of the first bus bar extending from a connection zone to the opposite side edge of the functional element) refers to the main direction of extension of the respective isolated segment. However, the respective isolated segment may, of course, also extend in the other two directions of the three-dimensional space, but the extension in these directions is smaller than in the first direction. Preferably, the extension in the second (e.g., its width) and third direction (e.g., its thickness) of each isolated segment of the first bus bar amounts to less than 10%, more preferably less than 5%, 3%, or 1%, of the (longest) extension in the first direction (i.e., its length). The width of the first bus bar and its thickness may, however, also be influenced by a surface area of the functional element connected thereto. Larger functional elements may require higher amounts of currents to be supplied to the functional element, and the width and / or the thickness of the first bus bar may be amended accordingly.

[0028] The at least two electrically isolated segments of the first bus bar, e.g., the first electrically isolated segment and / or the second electrically isolated segment, may have different shapes. The first segment preferably has an L-shape (in a plan view of the functional element), wherein the second segment preferably has an l-shape. In case there are more than two electrically isolated SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0029] 6 segments, preferably one segment has the l-shape wherein the other segments have the L- shape. This design with one l-shape and at least one L-shape allows to produce the at least two electrically isolated segments from one elongated rectangular (in the plan view) bus bar, as is explained in more detail with respect to the method for producing the laminated pane having the functional element (see below). More complex patterns, such as geometrical shapes with nonlinear or wave-shaped outlines are also envisaged by the inventors.

[0030] In a preferred embodiment, the at least two electrically isolated segments of the first bus bar extend at an angle of -20° to +20° relative to a second side edge interconnecting the first side edge and the third side edge of the functional element, particularly preferably they are arranged at an angle of 0°± 5° relative to the second side edge. The extension of the at least two electrically isolated segments of the first bus bar along the second side edge allows to increase the area of the functional element being available for through-vision (i.e. , minimizing the area covered by the first bus bar).

[0031] In a preferred embodiment, a length of the first bus bar equals at least 70% of a length of the nearest side edge of the functional element, preferably at least 90%. More simply put, the longest length of the individual electrically isolated segment of the first bus bar extends with the specified length, the other ones of the electrically isolated segments may be shorter. Preferably, the first bus bar is arranged on the side edge of the functional element on which no second bus bar is situated. Such an arrangement of the first and second bus bar at different side edges of the functional element enables easy attachment of the bus bars on the surface electrodes, which will be discussed in detail within the method for producing the laminated pane according to the invention. The second bus bar may, however, also be arranged on the same side edge as the first bus bar. Such an arrangement may be used in cases where both connection zones are preferably arranged in one region of the laminated pane, e.g. in one corner of the laminated pane. The first bus bar and the second bus bar may also start from the same corner area (i.e. close to the point of intersection between two adjacent side edges of the functional element) along different side edges of the functional element. For example, the first bus bar may extend along the second side edge whereas the second bus bar extends along the first side edge, both starting close to the point of intersection between the first side edge and the second side edge. However, preferably the first bus bar extends along at least 70% of the nearest side edge of the functional element. This allows to reliably supply all electrically isolated segments of the first flat electrode with electric power. SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0032] 7

[0033] In a preferred embodiment, each of the at least two electrically isolated segments of the first flat electrode are contacted by one of the at least two electrically isolated segments of the first bus bar. More specifically, each electrically isolated segment of the first flat electrode is electrically conductively contacted with one electrically isolated segment of the first bus bar. This allows to provide each electronically isolated segment of the first flat electrode with the power necessary for switching the respective segment whilst requiring only minimal surface space on the first flat electrode.

[0034] In a preferred embodiment, the first segment of the at least two electrically isolated segments of the first bus bar extends from the connection zone arranged at the first side edge to the opposite third side edge of the functional element, wherein a second segment of the at least two electrically isolated segments of the first bus bar extends less than 50%, preferably less than 30%, of a distance between the connection zone and the opposite third side edge. In other words, the first segment extends from connection zone arranged at the first side edge to the third side edge while the second segment extends for less than 50% of this distance, measured in parallel to the nearest side edge of the functional element. This allows to specifically connect the respective segments of the first flat electrode to the first bus bar while also reducing the surface space required on the first flat electrode.

[0035] In a preferred embodiment, the first bus bar and / or the second bus bar comprise an electrically conductive structure, preferably made of a material with silver, and / or have a thickness of 5 pm to 40 pm. This allows to create bus bars having a sufficient electric conductivity whilst also being flat enough to be included in the laminated pane.

[0036] In a preferred embodiment, the bus bars are implemented as a printed and baked conductive structure. The printed bus bars contain at least one metal, preferably silver. The electrical conductivity is preferably realized via metal particles contained in the bus bar, particularly preferably via silver particles. The metal particles can be situated in an organic and / or inorganic matrix such as pastes or inks, preferably as baked screen printing paste with glass frits. The layer thickness of the printed bus bars is preferably from 5 pm to 40 pm, particularly preferably from 8 pm to 20 pm, and most particularly preferably from 10 pm to 15 pm. Printed bus bars with these thicknesses are technically simple to realize and have advantageous current carrying capacity.

[0037] Alternatively, the bus bars are implemented as strips of an electrically conductive film. In that case, the bus bars contain, for example, at least aluminum, copper, tinned copper, gold, silver, zinc, tungsten, and / or tin or alloys thereof. The strip preferably has a thickness of 10 pm to SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0038] 8

[0039] 500 m, particularly preferably of 30 pm to 300 pm. Bus bars made of electrically conductive films with these thicknesses are technically simple to realize and have advantageous current carrying capacity. The strip can be electrically conductively contacted with the flat electrode, for example, via a soldering compound, an electrically conductive adhesive, or an electrically conductive adhesive tape, or by direct placement. To improve the conductive connection, a silver-containing paste, for example, can be arranged between the flat electrode and the bus bar.

[0040] In a preferred embodiment, the first flat electrode and / or the second flat electrode contain at least a metal, a metal alloy, or a transparent conductive oxide, and / or have a thickness of 10 nm to 2 pm. The flat electrodes are preferably transparent. Here, “transparent” means permeable to electromagnetic radiation, preferably electromagnetic radiation of a wavelength from 300 nm to 1 .300 nm and, in particular, to visible light. Electrically conductive layers according to the invention are known, for example, from DE 20 2008 017 611 U1 , EP 0 847 965 B1 , or WO2012 / 052315 A1. They typically contain one or more, for example, two, three, or four, electrically conductive, functional individual layers. The functional individual layers preferably contain at least one metal, for example, silver, gold, copper, nickel, and / or chromium, or a metal alloy. The functional individual layers particularly preferably contain at least 90 wt.-% of the metal, in particular at least 99.9 wt.-% of the metal. The functional individual layers can be made of the metal or the metal alloy. The functional individual layers particularly preferably contain silver or a silver-containing alloy. Such functional individual layers have particularly advantageous electrical conductivity with, at the same time, high transmittance in the visible spectral range. The thickness of a functional individual layer is preferably from 5 nm to 50 nm, particularly preferably from 8 nm to 25 nm. In this thickness range, advantageously high transmittance in the visible spectral range and particularly advantageous electrical conductivity are achieved.

[0041] The flat electrodes can in principle be formed by any electrically conductive layer that can be electrically contacted.

[0042] The functional element is preferably a multilayer film with two outer carrier films. In such a multilayer film, the flat electrodes and the active layer are arranged between the two carrier films. Here, “outer carrier film” means that the carrier films form the two surfaces of the multilayer film. The functional element can thus be provided as a laminated film that can be processed advantageously. The functional element is advantageously protected against damage, in particular, corrosion, by the carrier films. The multilayer film contains, in the order indicated, at SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0043] 9 least the first carrier film, the first flat electrode, the active layer, the second flat electrode, and the second carrier film.

[0044] Preferably, the first carrier film and / or the second carrier film contain(s) at least one polymer that does not fully melt in the autoclave process, preferably polyethylene terephthalate (PET). Particularly preferably, the first and the second carrier film are made of a PET film. This is particularly advantageous in terms of the stability of the multilayer film. The carrier films can, however, also contain, for example, ethylene vinyl acetate (EVA) and / or polyvinyl butyral (PVB), polypropylene, polycarbonate, polymethyl methacrylate, polyacrylate, polyvinyl chloride, polyacetate resin, casting resins, acrylates, fluorinated ethylene-propylenes, polyvinyl fluoride, and / or ethylene tetrafluoroethylene. The thickness of each carrier film is preferably from 0.1 mm to 1 mm, particularly preferably from 0.1 mm to 0.2 mm. The carrier films according to the invention are preferably transparent. The flat electrodes are preferably arranged on one surface of the carrier film, i.e. , on exactly one of the two sides of the carrier film (i.e., on its front side or its back side). The carrier films are oriented in the layer stack of the multilayer film such that the flat electrodes are arranged adjacent the active layer.

[0045] In the context of the invention, the term “electrically adjustable optical properties” means those properties that are infinitely adjustable, but also those that can be switched between two or more discrete states.

[0046] In addition to the active layer and the flat electrodes, the functional element can, of course, have other layers known per se, for example, barrier layers, blocking layers, anti refl ection layers, protective layers, and / or smoothing layers.

[0047] In an advantageous embodiment, the functional element of the laminated pane according to the invention is a PDLC functional element (polymer dispersed liquid crystal). The active layer of a PDLC functional element contains liquid crystals that are embedded in a polymer matrix. When no voltage is applied to the planar electrodes, the liquid crystals are aligned in a disorderly manner, resulting in strong scattering of the light passing through the active layer. When a voltage is applied to the planar electrodes, the liquid crystals align themselves in a common direction and the transmittance of light through the active layer is increased.

[0048] In other possible embodiments, the active layer is for example an SPD, an electrochromic, or an electroluminescent layer.

[0049] In another possible embodiment the functional element is a guest-host element. SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0050] 10

[0051] Functional elements as multilayer films are commercially available. The functional element to be integrated is typically cut or segmented in the desired shape and size from a multilayer film of larger dimensions. This can be done mechanically, for example, with a knife. In an advantageous embodiment, the segmenting is done using a laser. It has been demonstrated that, in this case, the side edge is more stable than with mechanical cutting / segmenting. With mechanically cut side edges, there can be a risk that the material will pull back, which is visually conspicuous and adversely affects the aesthetics of the pane.

[0052] In a preferred embodiment, the intermediate layer has a first thermoplastic laminating film, which is arranged between the functional element and the first pane, and has a second thermoplastic laminating film, which is arranged between the functional element and the second pane. The functional element is integrated between the first pane and the second pane of the laminated pane via an intermediate layer. The intermediate layer preferably comprises a first thermoplastic laminating film, which bonds the functional element to the first pane, and a second thermoplastic laminating film, which bonds the functional element to the second pane. Typically, the intermediate layer is formed by at least the first and the second thermoplastic laminating film, which are arranged flat atop one another and are laminated to one another, with the functional element inserted between the two layers. The regions of the laminating films overlapping the functional element then form the regions that bond the functional element to the panes. In other regions of the pane where the thermoplastic laminating films make direct contact, they can fuse during lamination such that the two original layers are no longer discernible and, instead, there is a homogeneous intermediate layer.

[0053] A thermoplastic laminating film can, for example, be formed by a single thermoplastic film. A thermoplastic laminating film can also be formed from sections of different thermoplastic films whose side edges are adjacent. In addition to a first thermoplastic laminating film or a second thermoplastic laminating film, additional thermoplastic laminating films can also be present. These can, if needed, also be used for embedding additional films comprising functional layers, for example, infrared-reflecting layers or acoustically damping layers.

[0054] The thermoplastic laminating films can also include tinted or colored regions. Such films can be obtained, for example, by coextrusion. Alternatively, an untinted film segment and a tinted or colored film segment can be combined to form a thermoplastic laminating film. The tinted or colored region can be homogeneously colored or tinted, in other words, can have locationindependent transmittance. However, the tinting or coloring can also be inhomogeneous; in SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0055] 11 particular, a transmittance progression can be realized. In one embodiment of a windshield, the transmittance level in the tinted or colored region decreases at least in sections with increasing distance from the upper roof edge. Thus, sharp edges of the tinted or colored region can be avoided such that the transition from the sun visor to the transparent region of the windshield is gradual, which appears more attractive aesthetically.

[0056] In an advantageous embodiment, the region of the thermoplastic laminated pane oriented in the direction of a pane used as an outer pane of the vehicle, i.e. , the region between the functional element and the outer pane, is tinted. This creates a particularly aesthetic impression of the vehicle observed from the outside. The region of the thermoplastic laminated pane between the functional element and the inner pane can, optionally, be additionally colored or tinted.

[0057] In a preferred embodiment, the functional element, more precisely the side edges of the functional element, is circumferentially surrounded by a thermoplastic frame film. The frame film is implemented like a frame with a recess into which the functional element is inserted. The thermoplastic frame film can be formed by a thermoplastic film in which the recess had been cut out. Alternatively, the thermoplastic frame film can also be composed of a plurality of film sections around the functional element. Thus, the intermediate layer is formed, in a preferred embodiment, from a total of at least three thermoplastic laminating films arranged flat atop one another, wherein the frame film, as the middle layer, has a recess in which the functional element is arranged. During production, the thermoplastic frame film is arranged between the first and the second thermoplastic laminating film, with the side edges of all thermoplastic films preferably situated congruently. The thermoplastic frame film preferably has roughly the same thickness as the functional element. This compensates for the local difference in thickness of the windshield, which is introduced by the locally limited functional element, such that glass breakage during lamination can be avoided.

[0058] The side edges of the functional element visible in through-vision through the laminated pane are preferably arranged flush with the thermoplastic frame film such that there is no gap between the side edge of the functional element and the associated side edge of the thermoplastic frame film. This is true in particular for the lower edge of a functional element as a sun visor of a windshield, in which this edge is typically visible. Thus, the boundary between the thermoplastic frame film and the functional element is visually less conspicuous.

[0059] Automobile glazing, in particular windshields, rear windows, and roof panes, usually have a surrounding peripheral masking print made of an opaque enamel, which serves in particular to SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0060] 12 protect the adhesive used for installation of the pane against UV radiation and to obscure it visually. This peripheral masking print is preferably also used to obscure the edges of the functional element that are situated in the edge region of the glazing. The bus bars and the required electrical connections are also installed in the region of the masking print. In this manner, the functional element is advantageously integrated into the appearance of the laminated pane. Preferably, at least the pane used as the outer pane has such a masking print; particularly preferably, both the first pane and the second pane (outer pane and inner pane) are printed such that through-vision is prevented from both sides.

[0061] The functional element can also have cutouts, for instance, in the region of so-called sensor windows or camera windows. These regions are provided to be equipped with sensors or cameras whose function would be impaired by an adjustable functional element in the beam path, for example, rain sensors.

[0062] The functional element is preferably arranged over the entire width of the laminated pane, minus an edge region on both sides with a width of, for example, 2 mm to 20 mm. The functional element preferably also has a distance from the upper edge of, for example, 2 mm to 20 mm. The functional element is thus encapsulated within the intermediate layer and is protected against contact with the surrounding atmosphere and against corrosion.

[0063] The first thermoplastic laminating film and the second thermoplastic laminating film and, optionally, the thermoplastic frame film as well, preferably contain at least polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), and / or polyurethane (Pll), particularly preferably PVB.

[0064] The thickness of each thermoplastic laminating film as well as the frame film is preferably from 0.2 mm to 2 mm, particularly preferably from 0.3 mm to 1 mm, in particular from 0.3 mm to 0.5 mm, for example, 0.38 mm.

[0065] The first pane and the second pane are preferably made of glass, particularly preferably of soda lime glass, as is customary for window panes. The panes can, however, also be made of other types of glass, for example, quartz glass, borosilicate glass, or aluminosilicate glass, or of rigid clear plastics, for example, polycarbonate or polymethyl methacrylate. The panes can be clear, or also tinted or colored. If the laminated pane is used as a windshield, it should have adequate light transmittance in the central field of vision, preferably at least 70% in the primary through- vision zone A per ECE-R43. SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0066] 13

[0067] The first pane, the second pane, and / or the intermediate layer can have other suitable coatings that are known per se, for example, anti-reflecting coatings, non-stick coatings, anti-scratch coatings, photocatalytic coatings, or solar protection coatings or low-E coatings.

[0068] The thickness of the first pane and the second pane can vary widely and thus be adapted to the requirements in the individual case. The first pane and the second pane preferably have thicknesses of 0.5 mm to 5 mm, particularly preferably of 1 mm to 3 mm.

[0069] The invention also includes a method for producing a laminated pane according to the invention, wherein at least a) a functional element is provided, the functional element comprising in the following order:

[0070] - a first carrier film,

[0071] - a first flat electrode,

[0072] - an active layer,

[0073] - a second flat electrode, and

[0074] - a second carrier film, b) a first bus bar is electrically conductively contacted to the first flat electrode in a first bus bar attachment area such that the first bus bar extends from a connection zone arranged on a first side edge of the functional element towards an opposite third side edge of the functional element, and a second bus bar is electrically conductively contacted to the second flat electrode in a second bus bar attachment area, c) at least one separating line extending from the first bus bar attachment area towards the second bus bar attachment area is introduced into the first flat electrode, d) the first bus bar and the first flat electrode having at least one separating line are segmented with a laser to obtain at least two electrically isolated segments of the first bus bar and to obtain at least two electrically isolated segments of the first flat electrode, wherein a first segment of the at least two electrically isolated segments of the first bus bar electrically conductively contacts a first segment of the at least two electrically isolated segments of the first flat electrode, and wherein a second segment of the at least two electrically isolated segments of the first bus bar electrically conductively contacts a second segment of the at least two electrically isolated segments of the first flat electrode, e) at least one first thermoplastic laminating film is placed on a first pane, the functional element is placed on the first thermoplastic laminating film, wherein at least one second thermoplastic laminating film and a second pane are arranged atop one another in this order on the functional element, and SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0075] 14 f) the first pane and the second pane are joined by lamination, wherein an intermediate layer with an embedded functional element is formed from the first thermoplastic laminating film and the second thermoplastic laminating film.

[0076] According to the invention, the first bus bar is electrically conductively contacted to the first flat electrode (step b)), at least one separating line is introduced into the first flat electrode extending from the first bus bar attachment area towards the second bus bar attachment area (step c)), and the first bus bar as well as the un-segmented remainder of the is first flat electrode is then segmented with the laser (step d)) to obtain the at least two electrically isolated segments of the first bus bar and the two electrically isolated segments of the first flat electrode. However, steps b) and c) may also be performed reverse order without departing from the scope of the invention, e.g. step c) may be performed before step b).

[0077] The inventors have found that the segmentation of the bus bar with the laser can also be used to segment the first surface electrode arranged directly underneath, allowing to manufacture the electrically isolated segments of the bus bar while also cutting the un-segmented remainder of the is first flat electrode in one go. Integrating the segmenting of the bus bar with the cutting of the functional element increases the flexibility by allowing for a more versatile number of segments to be created without prior preparation of the bus bars for the laser process; this also reduces costs and complexity by reducing the number of parts required for electrically contacting the first bus bar to the first flat electrode. Moreover, by using a laser in step d), more complex patterns for the first and / or second isolated segments of the first bus bar can be realized, while also achieving the required electrical isolation therebetween. This increases precision (especially compared to manual cutting of the bus bars as previously known by the inventors) and allows to fully automate the method for producing the laminated pane.

[0078] The functional element is preferably provided in the form of a multilayer film comprising, as set out above, the first carrier film, the active layer, and the second carrier film, wherein the surface electrodes are attached on the surfaces of the carrier films facing the active layer. The advantage of a multilayer film with electrically switchable optical properties resides in simple production of the laminated pane. The actual functional element is advantageously protected against damage, in particular corrosion, by the carrier films and can be prepared before production of the laminated pane even in relatively large quantities, which can be desirable for economic and technical processing reasons. The multilayer film can, during production of the laminated pane, simply be inserted into the composite, which is then laminated using conventional methods. SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0079] 15

[0080] The introduction of the at least one separating line in step c) is preferably done by a laser method. Preferably, the step c) is performed independently of step d), i.e. using separate laser cutting machines which are each specifically designed for introducing the at least one separating line into the first flat electrode (step c)) or segmenting the first bus bar (step d)). The inventors have found that performing the steps c) and d) using specifically designed laser cutting machines (e.g. having the specified wavelength or specifically designed optical systems) may improve speed and accuracy. However, combined laser cutting machines can also be envisaged, thereby allowing to perform steps c) and d) on the same laser machine, preferably using only one (possibly adjustable) laser source.

[0081] The separating lines are preferably generated by means of laser-induced degeneration within the first surface electrode. One such laser-induced degeneration is, for example, the removal of the surface electrode or a chemical change in the surface electrode. By means of the laser-induced degeneration, an interruption of the electrical conductivity of the layer is achieved. A pulsed solid- state laser is preferably used as the laser, however other types such as diode lasers, fiber laser, etc. may also be used. The separating lines are preferably produced through the carrier film nearest the surface electrode to be processed. The laser is focused through this carrier film onto the surface electrode. However, the separating lines may also be produced through the carrier film opposite to the electrode to be processed. Furthermore, also multiple electrodes may be processed in one laser cutting operation.

[0082] The electrical contacting of the surface electrodes of the functional element is preferably done after introduction of the separating lines but can optionally also take place before that.

[0083] The bus bars are preferably realized in the form of a printed and / or burnt-in conductive structure. The printed and / or burnt-in bus bars contain at least one metal, preferably silver. The electrical conductivity is preferably realized via metal particles contained in the bus bar, particularly preferably via silver particles. The metal particles can be situated in an organic and / or inorganic matrix such as pastes or inks, preferably as baked screen printing paste with glass frits. The layer thickness of the printed bus bars is preferably from 5 pm to 40 pm, particularly preferably from 8 pm to 20 pm, and most particularly preferably from 10 pm to 15 pm. Printed bus bars with these thicknesses are technically simple to realize and have advantageous current carrying capacity. Suitable silver printing pastes are available commercially and are known to the person skilled in the art. SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0084] 16

[0085] For the selective contacting of a surface electrode with a bus bar, the surface electrode must first be exposed from the multilayer film. Here, in a first step, one carrier film of the multilayer film including the surface electrode situated on the carrier film is cut back. The active layer thus exposed is removed, for example, by mechanical abrasion using a solvent. After removal of the active layer, the adjacent surface electrode is exposed and can be electrically conductively contacted by printing the bus bar.

[0086] When the described contacting method is used, the contacting of the first and the second bus bar is done on the first or second surface electrode starting from different surfaces of the multilayer film. Thus, for the contacting of a first surface electrode on a first carrier film, the second carrier film including the second surface electrode situated on the second carrier film is cut back, the active layer is removed, and the bus bars are attached from the side of the removed second carrier film. Analogously, for the contacting of the second surface electrode on the second carrier film, the first carrier film including the first surface electrode situated on the first carrier film is cut back. Accordingly, the first bus bar and the second bus bar are not positioned congruently when this method is used.

[0087] The bus bars are provided, in a manner known to the person skilled in the art, with connection cables, for example, in the form of flat conductors that are routed out of the pane composite in order to be connected to an external power source. The first bus bar is, however, only supplied with connection cables in the connection zone, thereby significantly reducing the amount of wiring required for electrical connection of the at least two segments of the first electrode.

[0088] Any prints present, for example, opaque masking prints and printed bus bars for the electrical contacting of the functional element are preferably applied by screen printing.

[0089] For incorporating the functional element into a laminated pane, a layer stack of the individual components is first created. For this, a first pane and a second pane, which function as the outer pane and the inner pane of the laminated pane, are provided. These can be planar or curved, preferably congruently curved. At least one first thermoplastic laminating film is placed on a first pane. The functional element is placed on the first thermoplastic laminating film. Optionally, a thermoplastic frame film that surrounds the functional element like a passepartout can be added. Arranged on the functional element, one over another are at least one second thermoplastic laminating film and a second pane. Optionally, in addition to the thermoplastic laminating films mentioned, further thermoplastic laminating films and / or carrier films with functional layers can also be inserted into the composite. SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0090] 17

[0091] The first pane and the second pane are bonded by lamination to form a laminated pane. The lamination is preferably done under the action of heat, vacuum, and / or pressure. It is possible to use lamination methods known per se, for example, autoclave methods, vacuum bag methods, vacuum ring methods, calender methods, vacuum laminators, or combinations thereof.

[0092] In a preferred embodiment, the segmenting with the laser in step d) of the first bus bar and the first flat electrode having the at least one separating line is performed using an infrared laser light source having a wavelength of at least 1 pm and at most 2 pm, preferably having a wavelength between 1000 nm and 1200 nm, more preferably between 1050 nm and 1100 nm, most preferably 1064 nm and / or 1030 nm. The segmenting with the laser in step d) may also be performed using a laser source having a wavelength of at least 200 nm and at most 600 nm (i.e., ultraviolet / visible light), preferably having a wavelength between 300 nm and 500 nm, most preferably 355 nm. The laser light source may also be a combined light source, having wavelengths in both spectrums, infrared and ultraviolet / visible light. The inventors have found that using the laser light with the specified wavelength(s) improves the segmenting performance of the laser when segmenting the first bus bar, especially in case of the bus bar being made from a material with silver.

[0093] After the segmenting of the first bus bar and the first flat electrode having the at least one separating line with the laser, a distance between respective segments of the first bus bar, measured in a plane parallel to the first flat electrode, amounts to at least 30 pm, 50 pm, or 100 pm, with a possible upper limit of, for example, 500 pm, 300 pm, or 200 pm (in descending order). In other words: Each segment of the first bus bar is spaced apart from a segment directly adjacent thereto by the preferred distance, thereby resulting in the preferable electrical isolation between the respective segments while also maintaining short processing times for the segmentation of the first bus bar and the first flat electrode with the laser.

[0094] In a preferred embodiment, the segmenting with the laser in step d) of the first bus bar and the first flat electrode having the at least one separating line is performed using a laser light source having a spot diameter of at most 200 pm, preferably 150 pm, 120 pm, 100 pm, 50 pm, or 30 pm, in a work zone. The term "work zone" refers to an area of the first bus bar and the first flat electrode to be segmented with the laser light, preferably extending along its thickness. In other words: the laser light is bundled such that its spot in the work zone on the first bus bar has the preferred diameter. This laser light spot performs the above mentioned laser-induced degeneration, thereby causing the interruption of the electrical conductivity in the first bus bar. Using the laser light SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0095] 18 source having the preferred spot diameter in the work zone allows to reliably achieve the interruption of the electrical conductivity in the first bus bar.

[0096] In a preferred embodiment, a focal point of the laser beam is selectively shifted in a thicknessdirection of first bus bar during the segmenting with the laser in step d). By shifting the focal point of the laser beam in the thickness-direction of the bus bar, thicker bus bars can also be reliably segmented, i.e. , the preferred interruption of the electric conductivity achieved.

[0097] In a preferred embodiment, the functional element is, prior to the segmenting with the laser in step d), arranged such that the first bus bar is below the first flat electrode when viewed in a vertical section through the functional element. By arranging the first bus bar below the first flat electrode, the material of the first bus bar and the first flat electrode being ablated by the laser- induced heat or by the laser-induced energy is subjected to gravity and therefore removed from the first bus bar and the first flat electrode. In other words: the bus bar material, e.g., silver, and the first flat electrode material moves vertically downwards away from the first bus bar and the first flat electrode, typically as stream of vapor containing gas and powder. This allows to achieve the preferred electrical isolation between the segments of the first flat electrode in the area of the first bus bar and the segments of the first bus bar in a reproducible manner.

[0098] In a preferred embodiment, at least during the segmenting with the laser in step d), an airflow is applied to a section of the functional element stack having the first bus bar. By applying the airflow to the section of the functional element having the first electrode, the ablated bus bar material (e.g., silver), and the first flat electrode material, which may be a stream of vapor, can be removed more efficiently while also allowing to selectively cool the first bus bar during and / or after the laser segmentation process.

[0099] The invention also includes the use of a laminated pane according to the invention as building glazing or vehicle glazing, preferably as vehicle glazing, in particular as a windshield or roof pane of a motor vehicle.

[0100] In general, “a” and “an” in the context of this disclosure are to be read as indefinite articles and thus always also as “at least one”, unless expressly stated to the contrary.

[0101] The invention is explained in detail with reference to drawings and exemplary embodiments. The drawings are schematic representations and are not to scale. The drawings in no way restrict the invention. They show in: SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0102] 19

[0103] Fig. 1a a plan view of an embodiment of a windshield according to the invention,

[0104] Fig. 1 b a plan view of an embodiment of a roof pane according to the invention,

[0105] Fig. 1c a cross-section through the windshield according to the invention of Fig. 1a along the section line C-C,

[0106] Fig. 1d a plan view of another embodiment of a roof pane according to the invention,

[0107] Fig. 2a the functional element 5 of Fig. 1a, 1b, 1c and 1 d,

[0108] Fig. 2b a cross-section through the functional element 5 of Fig. 2a along the section line

[0109] A-A',

[0110] Fig. 2c a cross-section through the functional element 5 of Fig. 2a along the section line B-B',

[0111] Fig. 3 a plan view of another embodiment of the functional element 5 of the windshield of Fig. 1a,

[0112] Fig. 4 an exemplary embodiment of the method according to the invention using a flowchart,

[0113] Fig. 5a an enlarged partial cross-section view of the functional element 5 of Fig. 2c during the segmenting process, and

[0114] Fig. 5b the enlarged partial cross-section view of the functional element 5 of Fig. 5a after the segmenting process.

[0115] Fig. 1a depicts a plan view of an embodiment of a laminated pane 100 according to the invention, which is implemented as a windshield of a motor vehicle (not shown).

[0116] The windshield comprises a first pane 1 , serving as an outer pane, and a second pane 2 serving as an inner pane. The inner pane is the pane directed toward the vehicle's interior, whereas the outer pane points toward the vehicle's surroundings. The first pane 1 and the second pane 2 are joined to one other via an intermediate layer 3. The first pane 1 has for example a thickness of 2.1 mm and is made of a green-colored soda lime glass. The second pane 2 has for example a thickness of 1.6 mm and is made of a clear soda lime glass. The laminated pane 100 provided as a windshield has a front roof edge D facing a roof of the motor vehicle in the installed position and an engine edge M facing an engine compartment of the motor vehicle in the installed position. SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0117] 20

[0118] The windshield is equipped with a functional element 5 as an electrically adjustable sun visor that is installed in a region above the central field of vision B (as defined in ECE-R43). The sun visor is formed by a commercially available PDLC multilayer film as a functional element 5, which is integrated into the intermediate layer 3. The height of the sun visor is, for example, 21 cm. The intermediate layer 3 comprises a total of three thermoplastic laminating films 6, 7, 8, which are in each case implemented as a thermoplastic film with a thickness of 0.38 mm made of PVB. The first thermoplastic laminating film 6 is bonded to the first pane 1 ; the second thermoplastic laminating film 7, to the second pane 2. The thermoplastic frame film 8 positioned therebetween has a cutout, into which the cut-to-size PDLC multilayer film is inserted with an exact fit, in other words, flush on all sides. The third thermoplastic layer thus forms, so to speak, a sort of passepartout for the functional element 5, which is thus encapsulated all around in a thermoplastic material and is protected thereby. The first thermoplastic laminating film 6 optionally has a tinted region 10 (see also Fig. 1c) that is arranged between the functional element 5 and the first pane 1. The light transmittance of the windshield is thus additionally reduced in the region of the sun visor and the milky appearance of the PDLC functional element 5 is mitigated in the diffusive state. The aesthetics of the windshield thus become significantly more attractive. In the case shown, the lower edges of the tinted region 10 and of the PDLC functional element 5 are arranged flush. This is, however, not necessarily the case.

[0119] The laminated pane 100 according to the invention has, in its embodiment as a windshield of Fig. 1a, a circumferential masking print 9, which conceals both the adhesive connection of the windshield to the vehicle body and the electrical contacting of the surface electrodes of the functional element 5. The circumferential peripheral masking print 9 is implemented by an opaque enamel on the interior-side surfaces (facing the interior of the vehicle in the installed position) of the first pane 1 and the second pane 2. The distance of the functional element 5 from the front roof edge D and the side edges of the windshield is less than the width of the masking print 9 such that first, second, and fourth side edges 5.1 , 5.2, 5.4 of the functional element 5, except for a third side edge 5.3 pointing toward the central field of vision B, are concealed by the masking print 9. The electrical connections and bus bars 18, 19 are also reasonably attached in the region of the masking print 9 and thus advantageously concealed.

[0120] The functional element 5 is controlled by a capacitive switch area arranged in the region of the sun visor, wherein a driver specifies the degree of darkening by means of the location at which he / she touches the pane. Alternatively, the sun visor can even be controlled by contactless SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0121] 21 methods, for example, by gesture recognition, or as a function of the pupil or eyelid state detected by a camera and suitable evaluation electronics.

[0122] Fig. 1b depicts a plan view of a laminated pane 100 according to a further aspect of the invention. In the example shown, the laminated pane 100 is implemented as a roof pane of the motor vehicle. Similarly to the windshield shown in Fig. 1a, the laminated pane 100 comprises, in the case of the roof pane, the first pane 1 , the second pane 2, which are joined to one another via the intermediate layer 3, and the functional element 5 that is embedded in the intermediate layer 3.

[0123] Fig. 1c depicts a cross-sectional view of the windshield of Fig. 1a along a section line C-C'. For sake of brevity, the following explanations relating to the functional element 5 are not repeated for the example of the laminated pane 100 being the roof pane (as shown in Fig. 1 b), as the functional element 5 can be integrated in the windshield and / or the roof pane, and its components are substantially the same in each case.

[0124] The side edges 5.1 , 5.2, 5.3, 5.4 of the functional element 5 are provided circumferentially with an edge seal (not shown in Fig. 1c) that is formed by a transparent acrylic adhesive tape. This prevents diffusion into or out of the active layer 11. Since the edge seal is transparent, the lower side edge i.e. , the third side edge 5.3), which is not concealed by the masking print 9, is also not distractingly visible. The edge seal runs circumferentially around the side edges 5.1 , 5.2, 5.3, 5.4 of the multilayer film and extends, starting from the side edges 5.1 , 5.2, 5.3, 5.4, a few millimeters over the surfaces of the carrier films 14, 15 facing away from the active layer 11. The edge seal 10 prevents, in particular, the diffusion of plasticizers and other adhesive components of the thermoplastic frame film 8 into the active layer 11 , as a result of which the aging of the functional element 5 is reduced.

[0125] A so-called “high flow PVB”, which has stronger flow behavior compared to standard PVB films, can preferably be used for the thermoplastic laminating films 6, 7 and the thermoplastic frame film 8. The layers thus flow more strongly around the functional element 5, creating a more homogeneous visual impression, and the transition from the functional element 5 to the frame film 8 is less conspicuous. The “high flow PVB” can be used for all or for only one or more of the thermoplastic films 6, 7, 8 having direct contact with the functional element 5.

[0126] Fig. 1d depicts a plan view of a laminated pane 100 according to a further aspect of the invention. In the example shown, the laminated pane 100 is implemented as a roof pane of the motor vehicle. The embodiment shown in Fig. 1d differs from the embodiment shown in Fig. 1b only in that the SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0127] 22 functional element 5 is larger as in Fig. 1 b and all side edges 5.1 , 5.2, 5.3, 5.4 of the functional element 5 are concealed by the masking print 9. The outer contour of the functional element 5 is shown schematically as dotted line in Fig. 1d.

[0128] Fig. 2a depicts a plan view of the functional element 5 of the windshield of Fig. 1a before integration of the functional element 5 into the windshield and of the functional element 5 of the roof pane of Fig. 1b and 1d before integration of the functional element 5 into the roof pane, wherein the bus bars 18, 19 are shown shaded (comparable to the section view of Fig. 2c) in order to facilitate the understanding. Figs. 2b and 2c depict cross-sections through the functional element of Fig. 2a along the section lines A-A' and B-B', respectively. The adjustable functional element 5 is a multilayer film, consisting of an active layer 11 between two surface electrodes 12, 13 and two carrier films 14, 15.

[0129] The active layer 11 contains a polymer matrix with liquid crystals dispersed therein, which align themselves as a function of the electrical voltage applied to the surface electrodes, by which means the optical properties can be adjusted. The carrier films 14, 15 are made of PET and have a thickness of, for example, 0.125 mm. The carrier films 14, 15 are provided with a coating of ITO facing the active layer 11 and having a thickness of approx. 100 nm, which form the first surface electrode 12 and the second surface electrode 13. The surface electrodes 12, 13 can be connected to the onboard electrical system via bus bars 18, 19 and connection cables (not shown).

[0130] The bus bars 18, 19 are formed by a silver-containing screen print. The first surface electrode 12 has three separating lines 16 with, in each case, a width of 200 pm, introduced by means of a laser process, and which divide the first surface electrode 12 into four segments 12.1 , 12.2, 12.3, 12.4. The separating lines 16 electrically isolate the segments 12 from one another. The number of segments 12 can be freely selected depending on the application or customer requirements. The first surface electrode 12 has one first bus bar 18 with one electrically isolated segment 18.1 , 18.2, 18.3, 18.4 of the first bus bar 18 contacting each of the four segments 12.1 , 12.2, 12.3, 12.4 of the first flat electrode 12.

[0131] As can be seen in Fig. 2a, the first bus bar 18 is arranged on the first flat electrode 12 in a first bus bar attachment area 12.5 such that the first bus bar 18 extends from a connection zone CZ arranged on the first side edge 5.1 of the functional element 5 towards the opposite third side edge 5.3 of the functional element 5. More specifically, a first segment 18.1 of the four electrically isolated segments 18.1 , 18.2, 18.3, 18.4 of the first bus bar 18 extends from the connection zone SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0132] 23

[0133] CZ arranged on the first side edge 5.1 of the functional element 5 towards an opposite third side edge 5.3 of the functional element 5 and electrically conductively contacts the first segment 12.1 of the four electrically isolated segments 12.1 , 12.2, 12.3, 12.4 of the first flat electrode 12. Likewise, a second segment 18.2, a third segment 18.3, and a fourth segment 18.4 extend from the connection zone CZ towards the opposite third side edge 5.3 of the functional element 5 and electrically conductively contact with the respective second segment 12.2, third segment 12.3 and fourth segment 12.4 of the first flat electrode 12.

[0134] The second bus bar 19 is arranged on the second flat electrode 13 in a second bus bar attachment area 13.1 , ensuring the electrical contacting of the second surface electrode 13, see also Fig. 2c. In the example shown, the second bus bar 19 extends from the first side edge 5.1 along the fourth side edge 5.4 towards the opposite third side edge 5.3 of functional element 5. A single second bus bar 19 suffices in this case for the electrical contacting of the functional element 5.

[0135] As can also be seen from Fig. 2a, the four electrically isolated segments 18.1 , 18.2, 18.3, 18.4 of the first bus bar 18 extend approx, parallel to the second side edge 5.2 of the functional element 5 interconnecting the first side edge 5.1 of the functional element 5 and the third side edge 5.3 of the functional element 5. Furthermore, a length of the first bus bar 18.1 bar equals a length of the nearest side edge, i.e., the second side edge 5.2 of the functional element 5. Furthermore, the first segment 18.1 of the four electrically isolated segments 18.1 , 18.2, 18.3, 18.4 of the first bus bar 18 extends from the connection zone CZ to the opposite fourth edge 5.4 of the functional element 5, and the fourth segment 18.4 of four electrically isolated segments 18.1 , 18.2, 18.3, 18.4 extends less than 50% of a distance between the connection zone CZ and the opposite fourth edge 5.4.

[0136] The electrically isolated segments 18.1 , 18.2, 18.3, 18.4 of the first bus bar 18 associated with the segments 12.1 , 12.2, 12.3, 12.4 of the first flat electrode 12 extend adjacent to each another from the second edge 5.2 to the fourth edge 5.4 of the functional element 5, as described above.

[0137] Fig. 2b depicts a cross-section along the section line A-A', which depicts the functional element 5 in more detail. As can be seen from Fig. 2b, the functional element 5 comprises, flat atop one another in this order the first carrier film 14, the first flat electrode 12 being divided into the four electrically isolated segments 12.1 , 12.2, 12.3, 12.4, the active layer 11 , the second flat electrode 13, and the second carrier film 15. SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0138] 24

[0139] Fig. 2c depicts a cross-section along the section line B-B', which depicts the contacting of the first bus bar 18 on the first surface electrode 12. The second carrier film 15, the second surface electrode 13, and the active layer 11 are removed in the region of the functional element 5 that is intended for the first bus bar 18. The first bus bar 18 is printed by screen printing onto the first surface electrode 12 thus exposed. A single second bus bar 19 suffices in this case for the electrical contacting of the functional element 5. In the region of the second bus bar 19, the first carrier film 14 together with the first surface electrode 12 is removed by cutting back the film. The active layer 11 is likewise removed in this region. The second bus bar 19 is printed onto the exposed second surface electrode 13 and thus makes electrical contact with the second surface electrode 13 in this region.

[0140] The inventors have found that connecting each of the electrically isolated segments 18.1 , 18.2, 18.3, 18.4 of the first bus bar 18 in the connection zone CZ reduces the amount of wiring necessary for contacting the isolated segments 12.1 , 12.2, 12.3, 12.4 of the first flat electrode 12 and improves the overall manufacturability of the laminated pane 100 having the functional element 5. Thereby the amount of wiring necessary for the contacting of the first flat electrode 12 is reduced, lowering the overall cost of the laminated pane 100, especially in case the amount of significantly more expensive copper wire (compared to silver) can be reduced. Furthermore, the complexity of the functional element 5 can be reduced, as the functional element 5 comprises a significantly reduced number of areas that require electrical connection, namely only the connection zone CZ on the first bus bar 18 and a further connection zone (in the area where the first side edge 5.1 and the fourth side edge 5.4 intersect, shown in the top left corner of Fig. 2a) on the second bus bar 19.

[0141] Fig. 3 depicts a further example of a plan view of the functional element 5 of the windshield of Fig. 1a before integration of the functional element 5 into the windshield (similarly to Fig. 2a). In Fig. 3, however, the second bus bar 19 is arranged approx, orthogonally to the first bus bar 18. More specifically, the first bus bar 18 extends from the first side edge 5.1 to the opposite third side edge 5.3 (as is shown in Fig. 2a) and the second bus bar 19 extends approx, parallel to the third side edge 5.3. Moreover, the functional element 5 shown in Fig. 3 is preferably integrated into the windshield such that the third side edge 5.3 is neighboring the roof edge of the windshield.

[0142] In the example shown, the separating lines 16, which divide the first surface electrode 12 into four segments 12.1 , 12.2, 12.3, 12.4, extend from the first bus bar attachment area 12.5 with the first bus bar 18 to the second bus bar attachment area 13.1 with the second bus bar 19 meanderingly. SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0143] 25

[0144] Irrespective of the shape of the individual segments 12.1 , 12.2, 12.3, 12.4, these are each contacted by one of the four electrically isolated segments 18.1 , 18.2, 18.3, 18.4 of the first bus bar 18, as described above.

[0145] Fig. 4 depicts, using a flowchart, an exemplary embodiment of the production method according to the invention comprising the steps:

[0146] P1) providing a functional element 5 comprising in the following order:

[0147] - a first carrier film 14,

[0148] - a first flat electrode 12,

[0149] - an active layer 11 ,

[0150] - a second flat electrode 13, and

[0151] - a second carrier film 15,

[0152] P2) electrically conductively contacting a first bus bar 18 to the first flat electrode 12 in a first bus bar attachment area 12.5 such that the first bus bar 18 extends from a connection zone CZ arranged on a first side edge 5.1 of the functional element 5 towards an opposite third side edge 5.3 of the functional element 5, and electrically conductively contacting a second bus bar 19 to the second flat electrode 13 in a second bus bar attachment area 13.1 ,

[0153] P3) introducing into the first flat electrode 12 at least one separating line 16 extending from the first bus bar attachment area 12.5 towards the second bus bar attachment area 13.1 , P4) segmenting the first bus bar 18 and the first flat electrode 12 with a laser to obtain at least two electrically isolated segments 18.1 , 18.2 of the first bus bar 18 and to obtain at least two electrically isolated segments 12.1 , 12.2 of the first flat electrode 12, wherein a first segment 18.1 of the at least two electrically isolated segments 18.1 , 18.2 of the first bus bar 18 electrically conductively contacts a first segment 12.1 of the at least two electrically isolated segments 12.1 , 12.2 of the first flat electrode 12, and wherein a second segment 18.2 of the at least two electrically isolated segments 18.1 , 18.2 of the first bus bar 18 electrically conductively contacts a second segment 12.2 of the at least two electrically isolated segments 12.1 , 12.2 of the first flat electrode 12,

[0154] P5) placing at least one first thermoplastic laminating film 6 on a first pane 1 , placing the functional element 5 on the first thermoplastic laminating film 6, wherein at least one second thermoplastic laminating film 7 and a second pane 2 are arranged atop one another in this order on the functional element 5, and SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0155] 26

[0156] P6) joining the first pane 1 and the second pane 2 by lamination, wherein an intermediate layer 3 with an embedded functional element 5 is formed from the first thermoplastic laminating film 6 and the second thermoplastic laminating film 7.

[0157] The segmenting with the laser in step P4 of the first bus bar 18 and the first flat electrode 12 is preferably performed using an infrared laser light source having a wavelength of 1064 nm and a spot diameter of 120 pm in a work zone on the first bus bar 18. A focal point of the laser beam is selectively shifted in a thickness-direction of first bus bar 18 during the segmenting with the laser in step P4. Furthermore, the functional element 5 is, prior to the segmenting with the laser in step P4, preferably arranged such that the first bus bar 18 is below the first flat electrode 12 when viewed in a vertical section through the functional element 5. In addition, at least during the segmenting with the laser in step P4, preferably an airflow is applied to a section of the functional element 5 having the first flat electrode 12.

[0158] The inventors have found that integrating the segmenting of the bus bar 18 into the production process of the functional element 5 and the laminated pane 100 increases the flexibility by allowing for a more versatile number of segments 18.1 , 18.2, 18.3, 18.4 to be created without prior preparation of the bus bars 18 for the laser process; this also reduces costs and complexity by reducing the number of parts required for electrically contacting the first bus bar 18 to the first flat electrode 12. Moreover, by using a laser in step P4, more complex patterns for the isolated segments 18.1 , 18.2, 18.3, 18.4 of the first bus bar 18 can be realized, while also achieving the required electrical isolation therebetween. This increases precision (especially compared to manual cutting / segmenting of the bus bars as previously known by the inventors) and allows to fully automate the method for producing the laminated pane 100.

[0159] Fig. 5a shows an enlarged partial cross-section view of the functional element 5 of Fig. 2c during the segmenting process as described with respect to Fig. 4. As can be seen in Fig. 5a, the functional element 5 is, prior to the segmenting with the laser cutting in step P4 (see Fig. 4), arranged such that the first bus bar 18 is below the first flat electrode 12 when viewed in a vertical section through the functional element 5. Furthermore, the first flat electrode 12 is supported by a mechanical support 17 or stand (triangular shape shown in Fig. 5a) during the segmentation process. By arranging the first bus bar 18 below the first flat electrode 12 and, by preferably supporting the first flat electrode 12 with the mechanical support 17, the material of the first bus bar 18 and the material of the first flat electrode 12 being ablated by the laser-induced heat or by the laser-induced energy is subjected to gravity and therefore removed from the first bus bar 18 SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0160] 27 and the first flat electrode 12. In other words: the bus bar material, e.g., silver, and the first flat electrode material moves vertically downwards away from the first bus bar 18 and the first flat electrode 12, typically as stream of vapor containing gas and powder (exemplified by cloud-like object shown in Fig. 5a). This allows to achieve the preferred electrical isolation between the segments 12.1 , 12.2, 12.3, 12.4 of the first flat electrode 12 in the area of the first bus bar 18 and the segments 18.1 , 18.2, 18.3, 18.4 of the first bus bar 18 in a reproducible manner.

[0161] Furthermore, it can be seen in Fig. 5a, that (at least during the segmenting with the laser in step P4) an airflow is applied (indicated by the arrow pointing left in Fig. 5a) to a section of the functional element 5 having the first bus bar 18. By applying the airflow to the section of the functional element having the first electrode 12, the ablated bus bar material (e.g., silver), and the first flat electrode material, which may be a stream of vapor, can be removed more efficiently while also allowing to selectively cool the first bus bar 18 and the first flat electrode 12 during and / or after the laser segmentation process.

[0162] Fig. 5b shows the enlarged partial cross-section view of the functional element 5 of Fig. 5a after the segmenting process. As can be seen in Fig. 5b, the segmenting of the bus bar 18 has been performed to create four electrically isolated segments 18.1, 18.2, 18.3, 18.4 of the first bus bar 18 whilst also creating an electrical isolation between the segments 12.1, 12.2, 12.3, 12.4 of the first flat electrode 12 in the area underneath the first bus bar 18.

[0163] SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0164] Reference numerals

[0165] 1 first pane

[0166] 2 second pane

[0167] 3 intermediate layer

[0168] 5 functional element (with electrically adjustable optical properties)

[0169] 5.1 first side edge of functional element 5

[0170] 5.2 second side edge of functional element 5

[0171] 5.3 third side edge of functional element 5

[0172] 5.4 fourth side edge of functional element 5

[0173] 6 first thermoplastic laminating film

[0174] 7 second thermoplastic laminating film

[0175] 8 thermoplastic frame film

[0176] 9 masking print

[0177] 10 tinted region of the first thermoplastic laminating film 6

[0178] 11 active layer of the functional element 5

[0179] 12 first surface electrode of the functional element 5

[0180] 12.1 first electrically isolated segment of first surface electrode 12

[0181] 12.2 second electrically isolated segment of first surface electrode 12

[0182] 12.3 third electrically isolated segment of first surface electrode 12

[0183] 12.4 fourth electrically isolated segment of first surface electrode 12

[0184] 12.5 first bus bar attachment area

[0185] 13 second surface electrode of the functional element 5

[0186] 13.1 second bus bar attachment area

[0187] 14 first carrier film

[0188] 15 second carrier film

[0189] 16 separating lines

[0190] 17 mechanical support

[0191] 18 first bus bar

[0192] 18.1 first electrically isolated segment of the first bus bar 18

[0193] 18.2 second electrically isolated segment of the first bus bar 18

[0194] 18.3 third electrically isolated segment of the first bus bar 18

[0195] 18.4 fourth electrically isolated segment of the first bus bar 18

[0196] 19 second bus bar SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT

[0197] 100 laminated pane

[0198] D front roof edge of laminated pane 100 R rear roof edge of laminated pane 100

[0199] M engine edge of laminated pane 100

[0200] S side edges of laminated pane 100

[0201] B central field of vision of laminated pane 100

[0202] CZ connection zone

[0203] A - A', B - B', C - C' section lines

Claims

SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCTClaims1. Laminated pane (100) with an electrically controllable functional element (5) which is switchable in segments, the laminated pane (100) at least comprising a first pane (1), a second pane (2), which are joined to one another via an intermediate layer (3), and a functional element (5) that is embedded in the intermediate layer (3), wherein the functional element (5) comprises, flat atop one another in this order: a first carrier film (14); a first flat electrode (12), wherein a first bus bar (18) comprising at least two electrically isolated segments (18.1 , 18.2) is arranged on the first flat electrode (12) in a first bus bar attachment area (12.5) such that the first bus bar (18) extends from a connection zone (CZ) arranged at a first side edge (5.1) of the functional element (5) towards an opposite third side edge (5.3) of the functional element (5); an active layer (11);- a second flat electrode (13), wherein a second bus bar (19) is arranged on the second flat electrode (13) in a second bus bar attachment area (13.1); and a second carrier film (15), wherein the first flat electrode (12) is divided into at least two electrically isolated segments (12.1 , 12.2) by at least one separating line (16) extending from the first bus bar attachment area (12.5) towards the second bus bar attachment area (13.1), wherein a first segment (18.1) of the at least two electrically isolated segments (18.1 , 18.2) of the first bus bar (18) electrically conductively contacts a first segment (12.1) of the at least two electrically isolated segments (12.1 , 12.2) of the first flat electrode (12), and wherein a second segment (18.2) of the at least two electrically isolated segments (18.1 , 18.2) of the first bus bar (18) electrically conductively contacts a second segment (12.2) of the at least two electrically isolated segments (12.1 , 12.2) of the first flat electrode (12).

2. Laminated pane (100) according to claim 1 , wherein the at least two electrically isolated segments (18.1 , 18.2) of the first bus bar (18) extend at an angle of -20° to +20° relative to a second side edge (5.2) interconnecting the first side edge (5.1) and the third side edge (5.3) of the functional element (5).SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT313. Laminated pane (100) according to claim 1 or 2, wherein a length of the first bus bar equals at least 70% of a length of the nearest side edge (5.1, 5.2, 5.3, 5.4) of the functional element (5).

4. Laminated pane (100) according to one of claims 1 to 3, wherein each of the at least two electrically isolated segments (12.1, 12.2) of the first flat electrode (12) are contacted by one of the at least two electrically isolated segments (18.1, 18.2) of the first bus bar (18).

5. Laminated pane (100) according to one of claims 1 to 4, wherein the first segment (18.1) of the at least two electrically isolated segments (18.1 , 18.2) of the first bus bar (18) extends from the connection zone (CZ) to the opposite third side edge (5.3) of the functional element (5), and wherein the second segment (18.2) of the at least two electrically isolated segments (18.1, 18.2) extends less than 50% of a distance between the connection zone (CZ) and the opposite third side edge (5.3).

6. Laminated pane (100) according to one of claims 1 to 5, wherein the first bus bar (18) and / or the second bus bar (19) comprise an electrically conductive structure, preferably made of a material with silver, and / or have a thickness of 5 pm to 40 pm.

7. Laminated pane (100) according to one of claims 1 to 6, wherein the first flat electrode (12) and / or the second flat electrode (13) contain at least a metal, a metal alloy, or a transparent conductive oxide, and / or have a thickness of 10 nm to 2 pm.

8. Laminated pane (100) according to any of claims 1 to 7, wherein the intermediate layer (3) has a first thermoplastic laminating film (6), which is arranged between the functional element (5) and the first pane (1), and has a second thermoplastic laminating film (7), which is arranged between the functional element and the second pane (2).

9. Method for producing a laminated pane (100), preferably a laminated pane (100) according to one of claims 1 to 8, the method comprising: a) providing a functional element (5) comprising in the following order: a first carrier film (14), a first flat electrode (12), an active layer (11), a second flat electrode (13), andSAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT32 a second carrier film (15); b) electrically conductively contacting a first bus bar (18) to the first flat electrode (12) in a first bus bar attachment area (12.5) such that the first bus bar (18) extends from a connection zone (CZ) arranged on a first side edge (5.1) of the functional element (5) towards an opposite third side edge (5.3) of the functional element (5), and electrically conductively contacting a second bus bar (19) to the second flat electrode (13) in a second bus bar attachment area (13.1); c) introducing into the first flat electrode (12) at least one separating line (16) extending from the first bus bar attachment area (12.5) towards the second bus bar attachment area (13.1); d) segmenting the first bus bar (18) and the first flat electrode (12) having the at least one separating line (16) with a laser to obtain at least two electrically isolated segments (18.1 , 18.2) of the first bus bar (18) and to obtain at least two electrically isolated segments (12.1 , 12.2) of the first flat electrode (12), wherein a first segment (18.1) of the at least two electrically isolated segments (18.1 , 18.2) of the first bus bar (18) electrically conductively contacts a first segment (12.1) of the at least two electrically isolated segments (12.1 , 12.2) of the first flat electrode (12), and wherein a second segment (18.2) of the at least two electrically isolated segments (18.1 , 18.2) of the first bus bar (18) electrically conductively contacts a second segment (12.2) of the at least two electrically isolated segments (12.1 , 12.2) of the first flat electrode (12); e) placing at least one first thermoplastic laminating film on a first pane (1), placing the functional element (5) on the first thermoplastic laminating film (6), wherein at least one second thermoplastic laminating film (7) and a second pane (2) are arranged atop one another in this order on the functional element (5); and f) joining the first pane (1) and the second pane (2) by lamination, wherein an intermediate layer (3) with an embedded functional element (5) is formed from the first thermoplastic laminating film (6) and the second thermoplastic laminating film (7).

10. Method according to claim 9, wherein the segmenting with the laser in step d) of the first bus bar (18) and the first flat electrode (12) is performed using an infrared laser light source having a wavelength of at least 1 pm and at most 2 pm and / or a laser source having a wavelength of at least 200 nm and at most 600 nm.SAINT-GOBAIN SEKURIT FRANCE 2024354- WO-PCT3311 . Method according to claim 9 or 10, wherein the segmenting with the laser in step d) of the first bus bar (18) and the first flat electrode (12) is performed using a laser light source having a spot diameter of at most 200 pm in a work zone.

12. Method according to one of claims 9 to 11 , wherein a focal point of the laser beam is selectively shifted in a thickness-direction of first bus bar (18) during the segmenting with the laser in step d).

13. Method according to one of claims 9 to 12, wherein the functional element (5) is, prior to the segmenting with the laser in step d), arranged such that the first bus bar (18) is below the first flat electrode (12) when viewed in a vertical section through the functional element (5).

14. Method according to one of claims 9 to 13, wherein, at least during the segmenting with the laser in step d), an airflow is applied to a section of the functional element (5) having the first bus bar (18).

15. Use of a laminated pane (100) according to one of claims 1 to 8 as building glazing or vehicle glazing, preferably as vehicle glazing, in particular as a windshield or roof pane of a motor vehicle.

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