Method for contacting a pdlc blank

Abstract

Proposed is a method for contacting a PDLC blank (32, 32') which is used in a vehicle window (12) in a PDLC arrangement (20), said method comprising the following steps: - providing a processed PDLC blank (32`) which comprises a first substrate film (22) with a first segmented, electrically conductive coating (28), a second substrate film (24) with a second segmented, electrically conductive coating (30) and a segmented PDLC layer (26) which is arranged between the two substrate films (22, 24), wherein the first segmented, electrically conductive coating (28) of the first substrate film (22) is exposed at least in one surface region (31); - removing, at least in some regions and / or sections, the first segmented, electrically conductive coating (28) at least in the exposed surface region (31) to form at least one insulation region (34), of a first segment of the first electrically conductive coating (28) and of a second segment of the first electrically conductive coating (28), wherein the first and the second segment of the first electrically conductive coating (28) are electrically insulated from one another; - applying electrically conductive conductor strips (36), wherein the electrically conductive conductor strips (36) extend from the first or second segment to a contacting region (38) for electrical contacting.

Description

[0001] Method for contacting a PDLC blank

[0002] The invention relates to a method for, in particular, electrically contacting a PDLC blank used in a vehicle window.

[0003] A vehicle window with a PDLC arrangement using a PDLC blank is known from the prior art and represents, for example, a roof element that is adjustable or fixed relative to a vehicle body. The vehicle window is a composite component comprising an outer window body and an inner window body. The outer window body forms an outer visible surface of the vehicle window, and the inner window body forms an inner visible surface of the vehicle window. The PDLC (polymer-dispersed liquid crystal) arrangement, which allows the light entry through the vehicle window to be controlled, is arranged between the outer window body and the inner window body. The PDLC arrangement can be switched between a blocking state, in which it acts like a diffuser, and a transmission state, in which light can pass through the vehicle window essentially unscattered.

[0004] The PDLC arrangement typically comprises two plastic films, each with a transparent, conductive coating on its inner side, and a PDLC layer arranged between the plastic films, which can be switched between the blocking state and the transmitting state by applying appropriate voltages. The conductive coatings of the plastic films each form an electrode layer, which can be connected to a control device and / or a voltage source by appropriate electrical contact. The electrical contact between the electrode layers is established particularly at the lateral edges of the PDLC arrangement.To enable a roller blind effect and / or partial shading of the vehicle window in question with such a PDLC arrangement, it is optionally possible to segment the PDLC layer and the electrically conductive coatings in order to control individual segments of the PDLC arrangement independently of one another and thus switch back and forth between the blocking state and the transmitting state. The individual segments increase the manufacturing effort for providing the respective contact.

[0005] To achieve contact, it is preferable to expose the corresponding electrically conductive coating at least partially in the edge regions. Residue-free exposure of the electrically conductive coating of the plastic films of the PDLC array has so far only been possible by subjecting the relevant electrically conductive coating to mechanical processing, which can lead to impairment and / or damage to the electrically conductive coating and / or coating quality.

[0006] After the electrically conductive coating has been exposed and / or after any PDLC polymer remaining on the electrically conductive coating has been cleaned off, the prior art generally involves applying a tin busbar by soldering or welding to provide the respective electrical contact between the individual segments. This tin busbar is placed on the electrically conductive coating depending on the respective position and / or arrangement of the respective PDLC segments in order to contact the individual PDLC segments or the individual segments of the electrically conductive coating segment by segment and thus to be able to supply current. Furthermore, one wire for each PDLC segment is inserted into the surrounding hot melt adhesive and one end of the wire is soldered and / or welded to the previously applied tin busbar, in particular using additional solder.The second end of each wire is also soldered and / or welded to a connector, such as a flexible printed circuit board (FPCB), using additional solder. The connector is then positioned in such a way that it will be positioned at the edge of the vehicle window during later use and can thus be connected to a power source and / or a control device.

[0007] This well-known process for providing contacts has a number of disadvantages.

[0008] For example, during soldering or welding, the solder can only be applied segment by segment slowly, necessitating multiple soldering stations operating in parallel to increase production speed. This leads to increased capital and operating costs. Furthermore, insufficient solder flexibility can lead to the solder detaching during the subsequent process steps, for example, if the PDLC array is necessarily bent and / or moved during the subsequent production process. Furthermore, the soldered tin busbar can act as a barrier to the venting of the film composite during the subsequent process steps due to the material application, which can, among other things, cause bubbles to form within the composite layer. This, in turn, leads to optical defects in the vehicle windshield.

[0009] Connecting the individual segments with wires also presents several disadvantages. For each PDLC segment, a (single) wire must be inserted and / or embedded into a surrounding hot melt adhesive, which requires highly precise work. Furthermore, the speed of the insertion process is limited. To increase this speed, multiple tool heads must be used, which increases capital and operating costs. Furthermore, parallel insertion of wires is not possible, requiring multiple tool heads at different work stations. Furthermore, a defective wire will destroy the entire film composite, meaning that in the case of a composite vehicle window, the entire window ultimately has to be replaced to restore functionality.The contact points of the wires to the tin busbar are also located along the entire exposed area of ​​the PDLC array, as each PDLC segment must be contacted with a wire. Each wire must also be soldered to two solder points, which further increases the manufacturing effort.

[0010] The aforementioned disadvantages must be overcome. In light of these, it is an object of the invention to provide a method for contacting a PDLC blank used in a vehicle window and / or a PDLC assembly, which improves manufacturing efficiency compared to the prior art and / or at least reduces the susceptibility of a subsequent PDLC assembly to defects due to a contact deficiency.

[0011] This object is achieved according to the invention by the method having the features of patent claim 1.

[0012] Advantageous embodiments of the invention are the subject of the dependent claims. The scope of the invention includes all combinations of at least two features disclosed in the description, the claims, and / or the figures. It is understood, in particular, that customary linguistic transformations and / or analogous replacements of respective terms within the scope of common linguistic practice, in particular the use of synonyms supported by generally accepted linguistic literature, are encompassed by the present disclosure content without being explicitly mentioned in their respective formulation.

[0013] According to the invention, a method for contacting a PDLC blank used in a vehicle window and / or in a PDLC arrangement is proposed. In its intended use, the PDLC blank is used in a PDLC arrangement, which in turn is used in a vehicle window to provide a shading function and / or a roller blind function. Even if the present invention is described for a PDLC arrangement, this is not to be understood as restrictive, so that all embodiments and / or descriptions - unless technically excluded - are also intended to apply to an LC arrangement. Thus, in the present case, the PDLC blank can be an LC blank and / or the PDLC arrangement can be an LC arrangement.

[0014] The method according to the invention comprises at least the following steps: In a first step, providing a processed PDLC blank comprising a first carrier film with a first segmented, electrically conductive coating, a second carrier film with a second, preferably segmented, electrically conductive coating, and a PDLC layer arranged between the two carrier films, wherein the first segmented, electrically conductive coating of the first carrier film is exposed at least in one surface region. The first segmented, electrically conductive coating can also be completely exposed. However, partial and / or section-wise and / or regional exposure of the first segmented, electrically conductive coating is preferred.In a further step, the first segmented, electrically conductive coating is removed at least in regions and / or sections at least in the exposed surface area to form at least one insulating region, a first segment of the first electrically conductive coating and a second segment of the first electrically conductive coating, wherein the first and second segments of the first electrically conductive coating are electrically insulated from one another. Particularly preferably, in this step, the first segmented, electrically conductive coating is removed at least in regions and / or sections at least in the exposed surface area to form at least one insulating region by means of which the individual segments of the first segmented, electrically conductive coating are electrically insulated from one another.It is understood that the removal may comprise a further segmentation of the first segmented, electrically conductive coating at least locally or regionally and / or in sections in order to form at least a first sub-segment of the first electrically conductive coating and a second sub-segment of the first electrically conductive coating, wherein the first and second sub-segments of the first electrically conductive coating are electrically insulated from one another. The number of required sub-sections may depend on the placement of the connection region and the number of segments in the first electrically conductive coating. In one embodiment, the removal step is carried out by ablation, e.g., with a laser. Alternatively, the removal may be carried out by etching or by mechanical removal, in particular with a brush and / or a knife.In a further step, electrically conductive conductor tracks are applied, in particular in parallel, wherein the electrically conductive conductor tracks extend from the first or second segment to a contacting region for electrical contacting. Thus, one conductor track preferably extends from the first segment to the contacting region and another conductor track from the second segment to the contacting region. In the further step, electrically conductive conductor tracks are preferably applied, in particular in parallel, to the at least one insulating region and / or to the first electrically conductive coating, wherein the individual segments of the first segmented, electrically conductive coating are each electrically contacted with a respective contacting region by means of the conductor tracks. The present invention relates to a method for insulating the individually applied conductor tracks from one another orto each other in such a way that segment-wise current supply is possible.

[0015] It goes without saying that further segments can also be present. It is also understood that the first electrically conductive coating does not have to be completely removed according to the invention, but that only part of the first electrically conductive coating can be removed. The first and / or the second segment can, for example, also comprise a path of the conductor track applied later, but are electrically insulated from one another. In this case, the conductor track is applied to the first electrically conductive coating. The path along which the respective conductor track is to be applied therefore does not necessarily have to be removed from the first electrically conductive coating according to the invention, but can remain, wherein such a segment is then nevertheless electrically insulated from another segment for at least partial removal of the first coating.Particularly preferably, the electrically conductive traces are applied to the insulating region and / or the first electrically conductive coating. It is also understood that the first and / or second coating do not necessarily have to be (pre-)segmented, but segmentation can also occur prior to provision. The second coating does not necessarily have to be segmented. It is only necessary that one of the two coatings be segmented so that the roller blind function and / or the segment-by-segment switching of the film can be implemented.

[0016] The invention thus relates to a contacting solution for the electrical connection and / or contacting of a preferably pre-segmented PDLC blank, in order to be able to supply current to it segment by segment during its intended use. In this way, a PDLC blank contacted according to the method can be used to form a PDLC arrangement that can be switched and / or supplied with current segment by segment during the application. This makes it possible, for example, to provide a blind function.

[0017] Preferably, the conductive traces are designed to have a relatively lower sheet resistance than the electrically conductive coatings. The lower layer resistance enables improved voltage transfer. The voltage can be applied to the film with relatively little voltage loss compared to an extended track of the coating alone. The extended conductive trace also provides a larger connection area to each segment of the carrier film, creating a synergistic effect of improved electrical connection.

[0018] The exposure of the first segmented, electrically conductive coating in at least one surface area can preferably be achieved in any desired manner. For example, the surface area can be exposed by cutting the second carrier film along with the underlying PDLC layer (also referred to as a kiss cut). Any residues of the PDLC layer on the first, segmented, electrically conductive coating can then be removed by cleaning.

[0019] According to the invention, the first segmented, electrically conductive coating is stripped at least in regions or partially to form the insulating region, ultimately enabling the segmented current supply to the individual PDLC segments. The first and second carrier films preferably comprise PET. The first segmented, electrically conductive coating and / or the second segmented, electrically conductive coating preferably comprise indium tin oxide (ITO). Other electrically conductive coatings can also be used.

[0020] The parallel and / or simultaneous application of the electrically conductive traces for all PDLC segments, in particular, offers a significant advantage over the prior art in terms of production time, particularly compared to welding and / or soldering a tin bus bar, as well as soldering and / or integrating individual wires. This offers a cycle time advantage. Due to the low material application, preferably in the pm range, the traces do not form a barrier to the venting of the film composite. Furthermore, when using an edge sealing concept in which the edges of the PDLC composite and / or the subsequent PDLC arrangement are sealed with liquid adhesive, the traces can be enclosed with the liquid adhesive due to their low material thickness. Likewise, a defect in a trace applied according to the invention no longer leads to the destruction of the entire film composite.Rather, only the PDLC assembly can be replaced, while the hot-melt adhesive films remain for reuse. This saves resources. According to the invention, the PDLC blank is contacted only at a central position, in particular by an (ultrasonic) weld and / or a soldered connection and / or a mechanical contacting method, preferably crimping, and / or a thermal weld and / or an adhesive connection, in particular by means of a conductive adhesive. The weld can be reliably realized, in particular, by an identical material pairing (PET to PET).

[0021] In one embodiment, the at least regional and / or section-wise removal of the first segmented, electrically conductive coating comprises decoating by a laser and / or etching by an etchant and / or mechanical removal, in particular by means of a brush. The first coating can also be removed abrasively. Removal by laser or etching is advantageous due to the achievable structural accuracy. Mechanical removal, e.g., by means of a rotating brush, is cost-effective. In principle, mechanical removal can also be achieved by scoring with a knife. This is a particularly simple way of isolating individual segments and requires a simple structural manufacturing setup. For example, a CO2 laser can also be used for removal. Other types of lasers can also be used.The laser is preferably operated in continuous wave mode, but can also be operated in pulsed mode. The laser power is preferably between 0.1 W and 500 W, particularly preferably between 0.5 W and 5 W. Thus, the laser power should preferably be at least in the low single-digit range, for example, less than or equal to 5 watts. For decoating, the laser beam is preferably focused on the first segmented, electrically conductive coating, ensuring a high power density and a thin cutting line.

[0022] In one embodiment, the application of electrically conductive conductor tracks comprises printing the at least one insulating region and / or the first electrically conductive coating with an electrically conductive paint and / or ink and / or applying an electrically conductive paste and / or ink. Such an ink and / or paint and / or paste particularly preferably exhibits high flexibility and is particularly suitable for printing on, for example, PET or, for example, coated PET substrates using ITO or other preferably flexible substrates. As a result, the printed and / or applied conductor tracks are not damaged during further production and / or during further production steps of the PDLC blank, even in the event of bending and / or warping.

[0023] In one embodiment, at least one stencil and / or a print mask is used during printing and / or application, and / or a digital printing process is employed. This allows a structured and predefined shape of the conductor tracks to be achieved. Furthermore, the conductor tracks can also have complex track paths.

[0024] In one embodiment, the electrically conductive tracks are routed in a mutually structured path to the contacting region, which is preferably arranged at an end region of the surface region. The contacting region preferably also serves as an electrical contact for the second electrically conductive coating.

[0025] In one embodiment, a contact section is formed at a respective end region of the respective conductor track arranged in the contacting region, which contact section is widened relative to a width of the respective conductor track. It is understood that the contact section of the respective conductor track can be widened, but this is not necessary. Widening can simplify contacting by means of a connector because the joining area is enlarged. The particularly parallel printing and / or application of the conductor tracks for contacting each individual segment is preferably carried out together with the printing and / or application of the preferred connection points and / or connection locations in the contacting region. Starting from the contacting region, a connection to a flexible connector, in particular to an FPBC, can be made, for example.In other words, a particularly flexible power supply cable and / or a particularly flexible connector is preferably connected in the contacting area to the respective conductor tracks, particularly individually or collectively, by welding, in particular by ultrasonic welding and / or by thermal welding and / or by soldering and / or by gluing and / or by clamping and / or by crimping and / or other mechanical contacting methods. The welding of an FPCB is preferably carried out to the printed contact points by means of ultrasonic welding. For example, a plug-in and / or clamping connection can be provided for the electrical connection between the contacting area and an electrical line, such as a cable, so that the contacting area itself or a further component arranged on the contacting area is designed accordingly.

[0026] In one embodiment, the electrically conductive traces are flexible after being printed onto the insulating area. This has the advantage that, unlike the prior art, even if the PDLC blank is bent, no trace detaches and potentially damages the PDLC contact.

[0027] In one embodiment, the electrically conductive traces are pre-dried after application, in particular by intense pulsed light (IPL). Pre-drying can also be carried out by a laser or thermally by hot air and / or infrared and / or an oven and / or by UV radiation. The optional pre-drying of the ink and / or paint and / or paste is carried out to achieve improved handling strength. The optional pre-drying is carried out to create adhesion to prevent damage to the traces in subsequent production steps. IPL has the advantage of a short cycle time, since only a short energy input time is necessary. It should be noted that IPL is a photonic drying process. Here, the cycle time is particularly short, in the milliseconds to seconds range.Compared to thermal drying, only a few seconds are required, for example, 5-30 seconds, and with photonic drying, for example, only milliseconds to seconds. Thermal drying, on the other hand, requires a cycle time of approximately 30 seconds to 30 minutes. Pre-drying and possibly post-drying, particularly in an autoclave, can have a positive effect on production time and / or cycle time.

[0028] The pre-dried or partially dried conductor tracks are preferably completely dried during the subsequent production steps (de-airing and autoclaving). De-airing and autoclaving are preferred because they allow a laminated safety glass composite to be created. In these processes, the pre-dried conductor tracks can be fully cured or sintered. This provides a cycle time advantage.

[0029] In one embodiment, at least the following steps are performed to provide the processed PDLC blank: heating the PDLC blank on the side of the first carrier film; and detaching a defined region of the second carrier film, together with a portion of the PDLC layer adhering in this region, from the first carrier film, so that the first conductive coating of the first carrier film is exposed in a surface area corresponding to the detached region of the second carrier film, preferably without residues of the PDLC layer. The first conductive coating is preferably freed from the PDLC layer without leaving any residue.

[0030] It has been shown that by heating one or both sides of the PDLC blank, the other side of the PDLC blank can be separated as a unit with the PDLC layer or mass due to the reduced adhesion forces between the PDLC mass and the conductive coating of the first carrier film. The cohesive forces in the PDLC mass and the adhesion forces between the PDLC mass and the electrically conductive coating of the second carrier film are maintained. This allows the PDLC mass to be removed from the electrically conductive coating of the first carrier film without damaging the electrically conductive coating. The removal process can be carried out quickly and with a high level of occupational safety, as no solvents are required. Furthermore, high reproducibility is guaranteed.The defined area of ​​the second carrier film is reproducible, so that a rapid industrial implementation of the method according to the invention is also possible.

[0031] The PDLC blank is, for example, a blank of a film composite formed from the first carrier film with the first electrically conductive coating, the second carrier film with the second electrically conductive coating, and the PDLC layer arranged therebetween. Cutting the PDLC blank can be integrated into the method according to the invention.

[0032] After carrying out the preferred method, the resulting PDLC blank processed in this way can be further processed according to the invention. In this case, the exposed conductive coating of the first carrier film can be contacted according to the invention, so that it can be connected to a control system, and the PDLC arrangement can be integrated into the composite structure of a vehicle window, so that it is arranged, for example, between two window bodies. The composite structure of the vehicle window can comprise further plastic films and / or layers that are arranged on one or more window bodies, and / or comprise an ambient light functionality. For example, at least one hot-melt adhesive film and / or a functional coating, such as, for example,arranged to reflect or absorb light of a specific wavelength.

[0033] The PDLC arrangement of the manufactured vehicle window forms, in particular, a shading arrangement that can be switched between a blocking state and a transmitting state by applying appropriate electrical voltages via the connected electrical control system. The vehicle window thus formed is particularly suitable as a pane of a vehicle roof, which can be part of a fixed roof element rigidly arranged relative to a vehicle body or of a cover element that can be displaced relative to the vehicle body by means of appropriate drive kinematics.

[0034] At least one of the two electrically conductive coatings of the two carrier films of the PDLC blank is segmented according to the invention, wherein separate contacting of the segments of the respective electrically conductive coating is possible by applying the method according to the invention.

[0035] In a specific embodiment of the method according to the invention, the PDLC blank is heated on the side of the first carrier film such that the first carrier film assumes a temperature of 60°C to 220°C, in particular a temperature of 60°C to 150°C, and preferably a temperature of 60°C to 100°C. These temperature ranges are particularly suitable when using a PET film as the carrier film, whose melting temperature is approximately 260°C.

[0036] The preferred method does not require any mechanical processing of the exposed electrically conductive coating, so that it is solvent-free and also free of cleaning traces.

[0037] In a specific embodiment, the defined area of ​​the second carrier film, together with the portion of the PDLC layer adhering to this area, is removed using a separating tool. The separating tool is preferably applied to the structure of the PDLC blank without contact with the electrically conductive coating of the first carrier film.

[0038] In order to clearly define the area in which the second carrier film, together with the portion of the PDLC layer adhering in this area, is detached from the first carrier film, in a preferred embodiment of the method, the defined area is created by severing the second carrier film along a cutting line without mechanically processing the first carrier film and its electrically conductive coating, i.e., without being affected by the cutting process. Such a cutting process is also frequently referred to as a kiss cut or half cut.

[0039] The defined region in which the electrically conductive coating of the first carrier film is exposed by the method according to the invention can have a strip shape, an L shape, a U shape, or a frame shape. It is also conceivable for the defined region to be formed by a local surface section, which can have any desired geometry. To assist in the detachment of the second carrier film and the portion of the PDLC layer adhering thereto from the first carrier film, in one specific embodiment the PDLC blank is held outside the defined region during detachment by means of a hold-down device.

[0040] To further support the detachment process and to ensure the adhesion forces between the PDLC mass or layer and the electrically conductive coating of the second carrier film, in a special embodiment the PDLC blank is cooled on the side of the second carrier film during the detachment of the defined area of ​​the second carrier film.

[0041] The present invention also proposes vehicle glazing comprising: a switchable film, wherein the switchable film has a first carrier film, a first segmented, electrically conductive coating, a second carrier film with a second, in particular segmented, electrically conductive coating, and a functional, in particular PDLC, layer arranged between the two carrier films; wherein the electrically conductive coating of the first carrier film is exposed in at least one surface area; and wherein the surface area comprises electrically conductive conductor tracks extending from each segment of the first electrically conductive coating, wherein each of the electrically conductive conductor tracks is electrically insulated from the other electrically conductive conductor tracks and extends from the respective segment of the first electrically conductive coating to a connection area.

[0042] In some embodiments, the electrically conductive traces can be isolated from one another by sub-segmenting the coating. The sub-segmentation can comprise further segmenting of the coating and provides an isolated path for the electrically conductive traces to travel from the individual coating segments to a connection region. In one embodiment, the sub-segmentation of the coating between the electrically conductive traces comprises segmentation lines that are separate from and overlap the coating segmentation. In one embodiment, the electrically conductive traces extend over the electrically conductive coating segments within a sub-segment, such that the electrically conductive traces each control one of the coating segments.In one embodiment, the electrical conductor tracks are preferably arranged such that at least two electrically conductive conductor tracks run parallel to each other over at least part of their length. The partial segmentation is preferably arranged such that sufficient space remains for positioning the electrical conductor tracks without overlapping the partial segmentation. In one embodiment, at least one electrically conductive conductor track extends from a region other than the connection region to the contacting region. In one embodiment, each electrically conductive conductor track extends from a region other than the contacting region to the contacting region.

[0043] Further advantages and advantageous embodiments of the subject matter of the invention can be found in the description, the drawings and the patent claims.

[0044] An embodiment of a method according to the invention is explained in more detail below with reference to the drawing. It shows:

[0045] Figure 1 is a perspective view of a roof area of ​​a motor vehicle;

[0046] Figure 2 shows a section through a pane of the vehicle roof;

[0047] Figure 3 is a schematic view of a PDLC blank contacted by the method according to the invention;

[0048] Figure 4 is a schematic view of a PDLC blank contacted by the method according to the invention;

[0049] Figure 5 is a schematic view of a PDLC blank contacted by the method according to the invention;

[0050] Figure 6 is a schematic view of a PDLC blank contacted by the method according to the invention; and

[0051] Figure 7 shows a schematic view of a PDLC blank contacted using the method according to the invention. Figure 1 shows a motor vehicle 10 comprising a vehicle roof 12 provided with a fixed roof element 14 that is rigidly or immovably connected to a vehicle body. The fixed roof element 14 forms a vehicle window that is designed with a shading function so that the incidence of light via the fixed roof element into an interior of the motor vehicle 10 can be controlled. The vehicle roof 12 extends along a vehicle longitudinal direction x and a vehicle width direction y. The vehicle longitudinal direction x is orthogonal to the vehicle width direction y. The vehicle window can also be referred to as vehicle glazing.

[0052] The fixed roof element 14 has a composite structure, which can be seen schematically in Figure 2 and which comprises an outer pane body 16, which forms an outer visible surface of the fixed roof element 14 facing the vehicle's surroundings, and an inner pane body 18, which forms an inner visible surface of the fixed roof element 14 accessible from the vehicle interior. A PDLC (polymer-dispersed liquid crystal) arrangement 20, which represents a shading system for the fixed roof element 14, is arranged between the outer pane body 16 and the inner pane body 18. The PDLC arrangement 20 is bonded to the outer pane body 16 and the inner pane body 18 via adhesive layers (not shown in detail) made of PCB (polyvinyl butyral). Other hot-melt adhesive films are also optionally possible.

[0053] The PDLC arrangement 20 comprises a first carrier film 22 and a second carrier film 24. A segmented PDLC layer 26 or a PDLC mass is arranged between the two carrier films 22 and 24, which forms the functionally active element of the PDLC arrangement 20. The carrier films 22 and 24, which can each be formed from a material such as PET or the like, each have a segmented, electrically conductive, transparent coating 28 or 30 on their side facing the PDLC layer 26, which forms an electrode layer and, in this case, is formed from an ITO coating (indium tin oxide coating). Other electrically conductive coatings are also conceivable. The segmentation of the coatings 28, 30 and the PDLC layer 26 is indicated in Figure 2 by vertical lines.The segmentation can be achieved, for example, by removing the coatings 28, 30 and / or by severing the PDLC layer 26 using a laser and / or a mechanical method. For this purpose, a CO2 laser, as previously described in more detail, can be used. Figure 2 shows a total of three segments, with each segment being designated by the respective reference numerals for the sake of clarity.

[0054] Through the segmented, electrically conductive coatings 28 and 30, a voltage can be applied to the likewise segmented PDLC layer 26 by means of a control device (not shown in detail), so that the transmission behavior of the PDLC layer 26 can be changed. This allows the PDLC layer 26 or the PDLC arrangement 20 to be adjusted between a blocking state, in which the PDLC layer 26 strongly scatters light due to the non-directional liquid crystals, and a transmission state in which portions of the light can enter the vehicle interior unscattered through the vehicle window 12. The PDLC layer 26 forms the actual shading element and comprises a polymer matrix in which liquid crystals are incorporated in droplet form.

[0055] In order to enable the individual PDLC segments to be energized and / or controlled, they must be electrically contacted. The first carrier film 22 of the PDLC arrangement 20 has, purely by way of example, a greater width in the vehicle width direction y of the fixed roof element 12 than the second carrier film 24, so that in each of the lateral edge regions, a surface region 31 of the first carrier film 22, designed as a contact strip (see an exemplary section of such a surface region 31 in Figure 3), is exposed. According to the invention, the first segmented, electrically conductive coating 28 can be contacted segment by segment via this respective exposed surface region 31 or connected to the control device (not shown in detail) via a flexible connector 29. The coating 30 of the second carrier film 24 is connected to the control device at another suitable location.Contacting of the second conductive coating 30 preferably takes place in the contacting area 38.

[0056] During the manufacture of the PDLC arrangement 20 or in preparation thereof for contacting and lamination of the composite structure shown in Figure 2, a PDLC blank 32 is preferably first provided. This preferably has the dimensions that the first carrier film 22 has in the installed position of the PDLC arrangement 20. Subsequently, a so-called kiss-cut process is preferably carried out on the PDLC blank 32, in which the second carrier film 24 is severed along a cutting line S without the separation process causing any mechanical stress on the first carrier film 22 and the coating 28 thereof.

[0057] The PDLC blank 32 is then heated, preferably on the side of the first carrier film 22, such that the first carrier film assumes a temperature of approximately 80°C to 100°C. Using a suitable separating tool (not shown), the area defined by the cutting line S, together with the section of the PDLC layer 26 adhering to the second carrier film 24 in this area, can be detached from the first carrier film 22 and its coating 28, in particular without leaving any residue, so that the exposed surface area 31 of the coating 28 of the first carrier film 22 results in the edge area. This process is preferably carried out along both lateral edges (viewed in the vehicle longitudinal direction x) of the PDLC blank 32, so that a thus processed PDLC blank 32' with the two lateral surface areas 31 is provided.

[0058] Figures 3 and 4 provide a more detailed look at the contacting of the thus processed PDLC blank 32 with the at least one exposed surface area 31. In Figures 3 and 4, the respective second carrier film 24 is transparent, so that the underlying segmented, electrically conductive coating 30 can also be seen in the non-exposed area of ​​the PDLC blank 32'. According to the invention, the segmented, electrically conductive coating 28 is removed at least in some areas and / or sections, at least in the exposed surface area 31, to form at least one insulating area 34, by means of which the individual segments of the first segmented, electrically conductive coating 28 are electrically insulated from one another.The at least regional and / or section-wise removal of the first segmented, electrically conductive coating 28 comprises decoating by a laser and / or etching by an etchant and / or a mechanical decoating process, such as grinding or brushing.

[0059] According to the invention, electrically conductive conductor tracks 36 are further applied to the at least one insulating region 34, wherein the individual segments of the first segmented, electrically conductive coating 28 are each electrically contacted by the conductor tracks 36. The application of electrically conductive conductor tracks 36 comprises printing the at least one insulating region with an electrically conductive paint and / or ink and / or applying an electrically conductive paste and / or ink. A stencil and / or a print mask can be used for this purpose. Digital printing methods can also be used. The electrically conductive conductor tracks 36 are, as can be seen from Figures 3 and 4, arranged in a structured course relative to one another and are led to a common contacting region 38. The contacting region 38 is arranged at an end region of the exposed surface region 31.

[0060] At a respective end region of the respective conductor track 36 arranged in the contacting region 38, a contact section 40 is formed, which is preferably widened relative to a width of the respective conductor track 36. In the present case, the respective contact section 40 is printed as a contact point.

[0061] Preferably, a particularly flexible connector 29 is connected, in particular individually, to the respective conductor tracks 36 in the contacting area 38 or at the respective contact sections 40 by ultrasonic welding and / or a mechanical contacting method such as clamping or crimping. The printed and / or applied conductor tracks 36 are flexible and are preferably pre-dried after printing and / or application.

[0062] The detailed view in Figure 4 shows the insulating region 34 and the non-deposited regions of the first, segmented, electrically conductive coating 28. The coating 28 is preferably removed only in those regions where an insulating effect is to be achieved in order to be able to control the segments individually. For efficiency reasons, the coating may not be removed in some places and may not be contacted by a conductor track 36 in order to accelerate the decoating process. These non-deposited regions, which are not contacted, are provided with the reference numeral 42 as an example.

[0063] Figure 4 also shows, by way of example, the respective welding points 44 or an adhesive point on the respective contact sections 40. It can also be seen that the individual segments of the first coating 28 are each contacted by a conductor track 36, wherein the respective conductor track 36 is also widened in the respective contact area and, in particular, forms a further contact point.

[0064] Figure 5 essentially corresponds to the structure shown in Figures 3 and 4, with the difference that the first electrically conductive coating 28 was not removed in the region of the electrical conductor tracks 36, so that the first electrically conductive coating 28 follows the course and / or path of the respective conductor track 36. Apart from the remaining segments, which serve for contacting, the first coating 28 has otherwise been removed. In this embodiment, the conductor tracks 36, preferably made of conductive ink, are each applied and / or printed onto the first segmented electrically conductive coating 28 (for example, an ITO layer). The first coating extends to the contact area.

[0065] Figure 6 essentially corresponds to the structure shown in Figures 3 and 4, with the difference that the first coating 28 has also been removed in an edge region of the surface region 31, and that no further non-decoated and non-contacted regions 42 of the first coating 28 are present.

[0066] Figure 7 essentially corresponds to the structure shown in Figures 3 and 4, with the difference that the first coating 28 was not removed across its entire surface, but rather the first coating 28 was only removed to segment the individual segments and to insulate the applied conductor tracks 36 from one another. In this way, current cannot preferably be transferred from one conductor track 36 to an adjacent conductor track 36. The at least one insulating region is thus strip- or line-shaped and electrically insulates the individual segments of the first coating from one another. This results in non-stripped and non-contacted regions 42 of the first coating 28, as well as segments of the first coating 28, onto which conductor tracks 36 are applied or printed, respectively, which lead to the respective contact section 40 in the contacting region 38.In the case of Figure 7, the segmentation was thus achieved merely by appropriately separating the first conductive coating 28, for example, using a laser or a knife. The segmentation lines 45 shown in dashed lines run from the left edge all the way to the right edge. Further segmentation lines 47 are preferably arranged around the conductor tracks 36 and their respective contact sections 40. The respective segmentation line 45, 47 is preferably incorporated into the electrically conductive coating. If the electrically conductive coating is removed, the segmentation line 45, 47 preferably no longer exists. The respective segmentation line 45, 47 is preferably provided in a plane below the printed conductor track 36. The respective horizontally extending segmentation line 45, 47 preferably belongs to the segmentation of the PDLC layer 26.

[0067] Figure 8 essentially corresponds to the structure shown in Figures 3 and 4, with the difference that the first coating 28 was not removed across the entire surface, but rather the first coating 28 was only removed to segment the individual segments, in order to provide sub-segments within at least one of the individual segments, and to insulate the applied conductor tracks 36 from one another. In this way, current cannot preferably be transferred from one conductor track 36 to an adjacent conductor track 36. In the case of Figure 8, the segmentation was therefore carried out by correspondingly removing the first conductive coating 28, for example by a laser or a knife. The segmentation lines 45 shown in dashed lines run from the left edge all the way to the right edge. The respective segmentation line 45 is preferably incorporated in the electrically conductive coating 28.The respective segmentation line 45 is preferably provided in a plane below the printed conductor track 36. The respective horizontally running segmentation line 45 preferably belongs to the segmentation of the PDLC layer 26. Furthermore, between the conductor tracks 36, three vertically running segmentation lines 46, shown in dashed lines, are shown, starting from the upper edge region. These segmentation lines 46 preferably serve to insulate the conductor track(s) 36 of a respective segment from the conductor track 36 of a respective adjacent segment and define the sub-segments. The segmentation lines 46 can intersect with the segmentation lines 45, so that electrically insulated paths are formed for the electrically conductive tracks 36. List of reference symbols.

[0068] 10 motor vehicle

[0069] 12 Vehicle roof

[0070] 14 fixed roof element

[0071] 16 disc outer body

[0072] 18 disc inner body

[0073] 20 PDLC array

[0074] 22 Carrier film

[0075] 24 carrier film

[0076] 26 PDLC layer

[0077] 28 Coating

[0078] 29 Connector

[0079] 30 Coating

[0080] 31 Area

[0081] 32 PDLC blanks

[0082] 32' machined PDLC blank

[0083] 34 Isolation area

[0084] 36 conductor tracks

[0085] 38 Contact area

[0086] 40 Contact section

[0087] 42 non-decoated and non-contacted area of ​​the coating

[0088] 44 Welding point

[0089] 45 Segmentation line

[0090] 46 Segmentation line

[0091] 47 Segmentation line x Vehicle longitudinal direction y Vehicle width direction

[0092] S cutting line

Claims

Patent claims 1. A method for contacting a PDLC blank (32, 32') used in a vehicle window (12) in a PDLC arrangement (20), comprising the following steps: - Providing a processed PDLC blank (32') comprising a first carrier film (22) with a first segmented, electrically conductive coating (28), a second carrier film (24) with a second, in particular segmented, electrically conductive coating (30) and a PDLC layer (26) arranged between the two carrier films (22, 24), wherein the first segmented, electrically conductive coating (28) of the first carrier film (22) is exposed at least in one surface region (31); - at least regionally and / or sectionally removing the first segmented, electrically conductive coating (28) at least in the exposed surface area (31) to form at least one insulating area (34), a first segment of the first electrically conductive coating (28) and a second segment of the first electrically conductive coating (28), wherein the first and second segments of the first electrically conductive coating (28) are electrically insulated from one another; and - applying electrically conductive conductor tracks (36), wherein the electrically conductive conductor tracks (36) extend from the first or second segment to a contacting region (38) for electrical contacting, wherein the electrically conductive conductor tracks (36) are electrically insulated from one another.

2. Method according to claim 1, characterized in that the at least regional and / or section-wise removal of the first segmented, electrically conductive coating (28) comprises decoating by a laser and / or etching by an etchant and / or mechanical removal, in particular by means of a brush and / or a knife.

3. Method according to claim 1 or 2, characterized in that the application of electrically conductive conductor tracks (36) comprises printing the at least one insulating region (34) and / or onto the first electrically conductive coating (28) with an electrically conductive paint and / or ink and / or applying an electrically conductive paste and / or ink.

4. Method according to claim 3, characterized in that at least one stencil and / or a printing mask is used for printing and / or applying and / or a digital printing process is used.

5. Method according to one of the preceding claims, characterized in that the electrically conductive conductor tracks (36) are guided in a mutually structured course to the in particular common contacting region (38), which is preferably arranged at an end region of the surface region (31).

6. The method according to claim 5, characterized in that a contact section (40) is formed at a respective end region of the respective conductor track (36) arranged in the contacting region (38), which contact section is widened relative to a width of the respective conductor track (36).

7. The method according to claim 5 or 6, characterized in that in the contacting area (38) a connector (29) is connected to the respective conductor tracks, in particular individually, by welding, in particular by ultrasonic welding and / or by thermal welding and / or by soldering and / or by gluing and / or by clamping and / or by crimping.

8. Method according to one of the preceding claims, characterized in that the electrically conductive conductor tracks (36) are flexible after printing onto the insulating area (34).

9. Method according to one of the preceding claims, characterized in that the electrically conductive conductor tracks (36) are pre-dried after application, in particular by intensive pulsed light and / or ultraviolet light and / or laser light and / or NIR light and / or thermally.

10. Method according to one of the preceding claims, characterized in that at least the following steps are carried out to provide the processed PDLC blank (32'): - heating a PDLC blank (32) on the side of the first carrier film (22); and - Detaching a defined region of the second carrier film (24) together with a section of the PDLC layer (26) adhering in this region from the first carrier film (22), so that the first conductive coating (28) of the first carrier film (22) is exposed in the surface region (31) corresponding to the detached region of the second carrier film (24).

11. The method according to claim 10, characterized in that the PDLC blank (32) is heated such that the first carrier film (22) assumes a temperature of 60°C to 220°C, in particular a temperature of 60°C to 150°C and particularly preferably a temperature of 60°C to 100°C.

12. The method according to claim 10 or 11, characterized in that the defined region of the second carrier film (24) is detached together with the section of the PDLC layer (26) adhering in this region by means of a separating tool.

13. Method according to one of claims 10 to 12, characterized in that the defined region is produced by severing the second carrier film (24) along a cutting line S, without the first carrier film (22) and the first segmented, electrically conductive coating (28) being mechanically processed.

14. Method according to one of claims 10 to 13, characterized in that the PDLC blank (32) is held outside the defined area of ​​the second carrier film (24) during detachment of the defined area by means of a hold-down device becomes.

15. The method according to any one of claims 10 to 14, characterized in that the PDLC blank (32) is cooled on the side of the second carrier film (22) during detachment of the defined region of the second carrier film (22).

16. The method according to any one of the preceding claims, characterized in that the electrically conductive traces (36) are applied to the insulating region (34) and / or the first electrically conductive coating.

17. Vehicle glazing comprising: a switchable film, wherein the switchable film has a first carrier film (22), a first segmented, electrically conductive coating (28), a second carrier film (24) with a second, in particular segmented, electrically conductive coating (30), and a functional, in particular PDLC, layer (26) arranged between the two carrier films (22, 24); wherein the electrically conductive coating (28) of the first carrier film (22) is exposed in at least one surface area (31); and wherein the surface area (31) comprises electrically conductive conductor tracks (36) extending from each segment of the first electrically conductive coating (28), wherein each of the electrically conductive conductor tracks (36) is electrically insulated from the other electrically conductive conductor tracks (36) and extends from the respective segment of the first electrically conductive coating (28) to a connection area.

Images