COMPOSITE PANE COMPRISING ELECTRICALLY CONTROLLABLE OPTICAL PROPERTIES AND CONTROL UNIT

Abstract

A composite pane with electrically controllable optical properties, includes an outer pane and an inner pane joined to one another via a thermoplastic intermediate layer, wherein a functional element with electrically controllable optical properties is integrated into the intermediate layer, wherein a securing element for reversibly securing a control unit is attached to a surface of the outer pane or of the inner pane facing away from the intermediate layer, and wherein a control unit suitable for controlling the optical properties of the functional element is arranged in the securing element.

Claims

1. A composite pane with electrically controllable optical properties, comprising an outer pane and an inner pane joined to one another via a thermoplastic intermediate layer, wherein a functional element with electrically controllable optical properties is integrated into the thermoplastic intermediate layer, wherein a securing element for reversibly securing a control unit is attached to a surface of the outer pane or of the inner pane facing away from the thermoplastic intermediate layer, and wherein a control unit adapted to control the optical properties of the functional element is arranged in the securing element.

2. The composite pane according to claim 1, wherein the securing element is fixedly connected to the surface of the outer pane or of the inner pane and the control unit is detachably connected to the securing element.

3. The composite pane according to claim 1, wherein the securing element is secured to the surface via a layer of an adhesive.

4. The composite pane according to claim 1, wherein the securing element has a plate that is connected over its entire surface to the surface of the outer pane or of the inner pane and which is provided with latching means that interact with complementary parts of the control unit in a force-fitting or form-fitting manner and thereby fix the control unit on the securing element.

5. The composite pane according to claim 1, wherein the securing element has an electrical contact region that is electrically conductively connected to flat electrodes of the functional element via electrical cables, and wherein a complementary contact region of the control unit is in contact with the contact region of the securing element so that the control unit is electrically conductively connected to the flat electrodes.

6. The composite pane according to claim 1, wherein the securing element is made of plastic, of a metal or a metal alloy, or of ceramic.

7. The composite pane according to claim 1, wherein the functional element is a PDLC functional element, an SPD functional element, or an electrochromic functional element.

8. The composite pane according to claim 1, which is provided with comprising an opaque masking print in a circumferential edge region of the composite pane, wherein the securing element is arranged in said edge region.

9. The composite pane according to claim 1, wherein the securing element is equipped with at least one sensor.

10. A method for producing a composite pane with electrically controllable optical properties, comprising: a) arranging a thermoplastic intermediate layer and a functional element with electrically controllable optical properties between an outer pane and an inner pane, b) joining the outer pane and the inner pane via the thermoplastic intermediate layer by lamination, c) attaching a securing element for reversibly securing a control unit to a surface of the outer pane or of the inner pane facing away from the thermoplastic intermediate layer, and d) arranging a control unit adapted to control the optical properties of the functional element in the securing element.

11. The method according to claim 10, wherein before or after step (d), electrical cables, via which the control unit is electrically conductively connected to flat electrodes of the functional element, are connected to the control unit.

12. The method according to claim 10, wherein the securing element has an electrical contact region that is electrically conductively connected to flat electrodes of the functional element via electrical cables, and wherein, in step (d), a complementary contact region of the control unit is brought into contact with the contact region of the securing element so that the control unit is electrically conductively connected to flat electrode of the functional element.

13. A method comprising providing a composite pane according to claim 1 as a window pane of a building, of a room inside the building, or of a vehicle.

14. The composite pane according to claim 9, wherein the at least one sensor is a light sensor and/or a temperature sensor.

15. The method according to claim 13, wherein the window pane is a windshield, a roof panel, a rear window, or a side window.

Description

[0056] The invention is explained in detail with reference to drawings and exemplary embodiments. The drawings are a schematic representation and are not to scale. The drawings in no way restrict the invention. They depict:

[0057] FIG. 1 a plan view of an embodiment of the composite pane according to the invention,

[0058] FIG. 2 a cross-section through the composite pane of FIG. 1,

[0059] FIG. 3 an enlarged representation of the region Z of FIG. 2,

[0060] FIG. 4 an enlarged representation of the region Y of FIG. 2,

[0061] FIG. 5 an enlarged representation of the region Y of FIG. 2 in an alternative embodiment, and

[0062] FIG. 6 an exemplary embodiment of the method according to the invention with reference to a flow chart.

[0063] FIG. 1, FIG. 2, FIG. 3, and FIG. 4 depict in each case a detail of a composite pane according to the invention with electrically controllable optical properties. The composite pane is, by way of example, provided as a roof panel of a passenger car, the light transmittance of which can be controlled electrically. The composite pane comprises an outer pane 1 and an inner pane 2 that are joined to one another via an intermediate layer 3. The outer pane 1 and the inner pane 2 are made of soda lime glass, which can optionally be tinted. The outer pane 1 has, for example, a thickness of 2.1 mm; the inner pane 2, a thickness of 1.6 mm.

[0064] The intermediate layer 3 comprises a total of three thermoplastic layers 3a, 3b, 3c, formed in each case by a thermoplastic film made of PVB with a thickness of 0.38 mm. The first thermoplastic layer 3a is bonded to the outer pane 1; the second thermoplastic layer 3b, to the inner pane 2. The third thermoplastic layer 3c positioned therebetween has a cutout into which a functional element 4 with electrically controllable optical properties is inserted with a substantially precise fit, i.e., roughly flush on all sides. The third thermoplastic layer 3c thus forms, so to speak, a sort of passepartout or frame for the roughly 0.4-mm-thick functional element 4, which is thus encapsulated all around in thermoplastic material and is thus protected. The functional element 4 is, for example, a PDLC multilayer film, that can be switched from a clear, transparent state into a cloudy, non-transparent (diffuse) state. The functional element 4 is a multilayer film consisting of an active layer 5 between two flat electrodes 8, 9 and two carrier films 6, 7. The active layer 5 contains a polymer matrix with liquid crystals dispersed therein, which orient themselves as a function of the electrical voltage applied on the flat electrodes, as a result of which the optical properties can be regulated. The carrier films 6, 7 are made of PET and have a thickness of, for example, 0.125 mm. The carrier films 6, 7 are provided with a coating of ITO with a thickness of roughly 100 mm facing the active layer 5, which form the flat electrodes 8, 9. The flat electrodes 8, 9 are connected via bus bars (not shown) (formed, for example by a silver-containing screen print) to electrical cables that establish the connection to a control unit 11.

[0065] This control unit 11 is attached by a securing element 10 to the interior-side surface of the inner pane 2 facing away from the intermediate layer 3. The securing element 10 is made, for example, of polyamide and fastened on the composite pane via a layer of an adhesive 12. The securing element 10 comprises a plate that is attached surface-to-surface to the composite pane and a side wall in the edge region of the plate. The plate and the side wall enclose a cavity that has an opening facing away from the composite pane. The control unit 11 can be inserted through this opening into the cavity, as a result of which a reversible, i.e., detachable, connection to the securing element 10 is achieved. For this purpose, a region or a plurality of regions of the side wall (latching lugs) extend beyond the surface of the control unit 11 facing away from the composite pane such that the control unit 11 latches in the securing element 10. During insertion and removal of the control unit 11, the flexible side wall (or a region thereof provided with the latching lugs) is bent slightly outward.

[0066] The electrical cables 14 are connected directly to the control unit 11 by means of a plug connection. On the other hand, the control unit 11 is connected to the onboard electrical system of the passenger car (not shown, for simplicity). The control unit 11 is suitable for applying, as a function of a switching signal specified by the driver, for example, by pressing a button, the voltage required for the desired optical state of the functional element 4, to the flat electrodes 8, 9 of the functional element 4.

[0067] The composite pane has a circumferential edge region that is provided with an opaque masking print 13. This masking print 13 is typically made of a black enamel. It is screen-printed as a printing ink with a black pigment and glass frits and baked into the pane surface. The masking print 13 is, by way of example, applied on the interior-side surface of the outer pane 1 and also on the interior-side surface of the inner pane 2. The side edges of the functional element 4 are concealed by this masking print 13. The securing element 10 with the control unit 11 is arranged in this opaque edge region, i.e., bonded to the masking print 13 of the inner pane 2. There, the control unit 11 does not interfere with the through-vision through the composite pane and is visually inconspicuous. In addition, there is a short distance to the side edge of the composite pane such that, advantageously, only short cables 14 are required for the electrical connection of the functional element 14.

[0068] FIG. 5 depicts another embodiment of the securing element 10 and the control unit 11, which differs from the embodiment of FIG. 4. The cables 14 are connected to the securing element with a plug connection and electrically conductively connected to a contact region 15. The control unit 11, which in this case is situated outside the securing element 10, has a contact region 15 complementary thereto. The contact regions 15, 15 are positioned and formed such that they come into contact with each other when the control unit 11 is inserted into the securing element 10. The control unit 11 then does not have to be wired specifically.

[0069] FIG. 6 depicts an exemplary embodiment of the production method according to the invention with reference to a flow chart.

LIST OF REFERENCE CHARACTERS

[0070] (1) outer pane [0071] (2) inner pane [0072] (3) thermoplastic intermediate layer [0073] (3a) first layer of the intermediate layer 3 [0074] (3b) second layer of the intermediate layer 3 [0075] (3c) third layer of the intermediate layer 3 [0076] (4) functional element with electrically adjustable optical properties [0077] (5) active layer of the functional element 4 [0078] (6) first carrier film of the functional element 4 [0079] (7) second carrier film of the functional element 4 [0080] (8) flat electrode of the functional element 4 [0081] (9) flat electrode of the functional element 4 [0082] (10) securing element for reversibly securing a control unit [0083] (11) control unit [0084] (12) adhesive [0085] (13) masking print [0086] (14) electrical cables [0087] (15) contact region of the securing element 10 [0088] (15) contact region of the control unit 11 [0089] X-X section line [0090] Y enlarged region [0091] Z enlarged region