Composite pane

Abstract

The present invention relates to a composite pane comprising a first pane (1; 7), a second pane (2; 7), and a bonding structure (3; 5; 6), the first pane (1; 7) being connected to the second pane (2; 7) via the bonding structure (3; 5; 6), the second pane (2; 7) having a coating (4), the coating (4) being designed to reflect polarised light incident directly on the second pane (2; 7) and to transmit light incident on the second pane (2; 7) through the first pane (1; 7) and the bonding structure (3; 5; 6), the composite pane comprising a coloured layer (5; 6; 7), characterised in that the coloured layer (5; 6; 7) has, in the L*a*b* colour space, an L* value between 70 and 100, in particular between 80 and 100, an a* value between -20 and 0, in particular between -10 and 0, and a b* value between -20 and 10, in particular between -10 and 10, the coloured layer (5; 6; 7) being designed to reflect more than 20% of infrared light, preferably more than 50%.

Description

[0001] SAINT-GOBAIN SEKURIT FRANCE 2024327-WO-PCT

[0002] 1

[0003] Composite disc

[0004] The present invention relates to a composite disk according to the preamble of claim 1.

[0005] Laminated glass is known from the prior art, particularly as windshields for motor vehicles. It is also known to project information for the driver of a motor vehicle onto the laminated glass. This can also be referred to as a head-up display, because the driver does not need to look at an instrument panel to receive the information.

[0006] From WO 2024 / 165281 A1, a display system for a vehicle with a laminated windscreen is known. The laminated windscreen comprises an outer pane with an outer surface and an inner surface, and an inner pane with an outer surface and an inner surface. The inner surface of the outer pane and the outer surface of the inner pane are bonded together via a thermoplastic interlayer.

[0007] WO 2024 / 002332A1 describes a head-up display (HUD) glass and a corresponding HUD system intended for use in vehicles. The glass consists of an outer and inner glass layer, an intermediate layer, and a reflective film layer on the inner glass layer. The reflective layer is designed to reflect p-polarized light, thereby reducing ghosting and improving the clarity of the projected HUD image. The film consists of at least one low-emissivity layer and a layered structure with alternating layers of high and low refractive indices. The invention aims to combine the performance of the HUD system with the requirements for thermal insulation and low radiation to increase the visual and thermal comfort of the vehicle occupants.

[0008] WO 20222 / 53584A1 discloses a laminated glass for vehicles, such as windshields or roof windows. The glass comprises an outer pane, an inner pane, and a thermoplastic interlayer. Between the two glass layers is an electrically conductive coating, which can serve, among other things, for heating or as an IR-reflecting layer, and at least one layer with selectively absorbing nanoparticles. This nanoparticle layer absorbs light in the wavelength range of 580 nm to 750 nm. This results in the SAINT-GOBAIN SEKURIT FRANCE 2024327-WO-PCT

[0009] The reddish tint, often caused by the conductive coating, is compensated for, and the overall color of the pane appears more neutral, bluish, or greenish. The goal is to create a more visually appealing pane with good heat-insulating properties that reduces the energy consumption of the air conditioning system.

[0010] The front panel has a display area and an imaging unit. The imaging unit is directed towards the display area and illuminates it with p-polarized radiation. A reflective coating suitable for reflecting p-polarized radiation is arranged on the inner surface of the inner panel. Starting from the inner surface of the inner panel, the reflective coating comprises, in the following order: a high-refractive-index layer with a refractive index greater than 1.9, a reflection-enhancing layer based on a metal or semiconductor, and a low-refractive-index layer with a refractive index of 1.6 or less.

[0011] In contrast, the present invention is based on the objective of creating a more visually appealing composite disc, a display system with such a composite disc and a motor vehicle with such a display system.

[0012] This problem is solved by a composite disc according to claim 1, a display system according to claim 12, and a motor vehicle according to claim 13. Embodiments of the invention are specified in the dependent claims.

[0013] The composite disc comprises a first disc, a second disc, and a connecting structure. The first disc is connected to the second disc via the connecting structure. It is particularly possible that both the first and second discs are bonded to the connecting structure by a material bond.

[0014] The compound structure can be based, for example, on polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), or polyurethane (PU), or on mixtures, copolymers, or derivatives thereof, particularly preferably on PVB. This means that the compound structure can contain the aforementioned polymer to a large extent (proportion greater than 50 wt%). In addition to the polymer, the compound structure can contain other additives, such as plasticizers, UV absorbers, or stabilizers. The compound structure can comprise one or more thermoplastic layers, for example, thermoplastic films. The thickness of the thermoplastic SAINT-GOBAIN SEKURIT FRANCE 2024327-WO-PCT

[0015] 3

[0016] The thickness of each layer is preferably from 0.2 mm to 2 mm. For example, the bond structure can comprise one or more PVB films with standard thicknesses of 0.38 mm or 0.76 mm.

[0017] The bonding structure can also be referred to as a bonding layer or intermediate layer, which can be single- or multi-layered.

[0018] The first and second panes are preferably glass panes, particularly preferably made of soda-lime glass, as is common for window panes. However, one or both panes can also be made of other types of glass, such as quartz glass, borosilicate glass, or aluminosilicate glass, or of rigid, clear plastics, such as polycarbonate or polymethyl methacrylate. The thicknesses of the first and second panes are preferably from 0.5 mm to 5 mm, and particularly preferably from 1 mm to 3 mm, and are independent of each other.

[0019] The second disk has a coating configured to reflect polarized light striking it directly. In particular, the coating can be configured to reflect more than 10%, and more preferably more than 15%, of the polarized light striking it directly. Furthermore, the coating is configured to transmit more than 70%, and more preferably more than 75%, of light striking the second disk through the first disk and the interconnection structure. For the purposes of this description, "light" refers specifically to light visible to the human eye.

[0020] The coating can, for example, be a reflective coating as described in WO 2024 / 165281 A1. In particular, it is possible for the coating to comprise several individual layers. These can, for example, be two dielectric layers with different refractive indices and one layer based on a metal or semiconductor, with the metal or semiconductor-based layer being positioned between the other two layers.

[0021] It is possible that the second pane is an inner pane. This could mean that, when using the laminated glass in a motor vehicle, it faces the interior, whereas in this case the first pane could be an outer pane facing the vehicle's surroundings. Preferably, the SAINT-GOBAIN SEKURIT FRANCE 2024327-WO-PCT

[0022] 4

[0023] The coating should be applied to a surface of the inner pane that faces the interior. This surface is particularly well-suited for projecting the information.

[0024] The composite panel includes a colored layer. This refers specifically to a layer that is transparent but reflects or scatters light in at least one wavelength range more strongly than light in other wavelength ranges. This creates the impression that the layer has a color. In the L*a*b* color space, the colored layer has an L* value between 70 and 100, particularly between 80 and 100, an a* value between -20 and 0, particularly between -10 and 0, and a b* value between -20 and 10, particularly between -10 and 10.

[0025] The color specified above can be either a transmission color or a reflection color. In both cases, the effects and advantages described in this description are achieved for the specified values ​​in the L*a*b* color space. The transmission color is measured with the light source D65 and a 10° detector at an incidence angle of 0° to the surface normal, with the light source directed at a first surface of the colored layer and the detector directed at a second surface of the colored layer. The reflection color is measured with the light source D65 and a 10° detector. The reflection color is measured when the colored layer is illuminated at an angle of 8° (incidence angle and observation angle) to the surface normal.

[0026] A key aspect of the invention is the realization that the coating of the second pane causes the laminated pane to appear yellow in the coating area, which some users perceive as an optical impairment. This is at least partially compensated for by the colored layer, resulting in a high-quality and harmonious overall appearance for the laminated pane. It is therefore particularly preferred if the colored layer is green and / or blue.

[0027] The L*a*b* color space, also known as the CIELAB or CIEL*a*b* color space, utilizes a three-dimensional space where the degree of perceived brightness, L*, is perpendicular to a color plane (a*, b*). The a* coordinate specifies the hue (hue and saturation) between green and red, and the b* coordinate specifies the hue between blue and yellow. The closer the a* and b* coordinates are to each other, the more the color changes. SAINT-GOBAIN SEKURIT FRANCE 2024327-WO-PCT

[0028] 5

[0029] The closer the values ​​are to 0, the more muted the color. For a*=0 and b*=0, a gray value is present on the brightness axis L*. Typically, the brightness level L ("Lightness") is defined for values ​​between 0 (black point) and 100 (white point), while a* and b* can take values ​​between -128 and 127.

[0030] The colored layer is designed to reflect more than 20%, preferably more than 50%, of infrared light. This is advantageous for mitigating the heating of the vehicle's interior when exposed to sunlight. The reflection of infrared light can be measured, for example, with a spectrometer. Integral values ​​can then be calculated from this measurement, for example, according to ISO DIN 5033 or EN 410.

[0031] This reflection of infrared light can be achieved, for example, by a metallic coating on the layer. The coating can contain silver or consist entirely of silver. For instance, the colored layer could be a polyethylene terephthalate (PET) film with a silver coating. Such PET films are commercially available. The PET film can have a thickness between 20 pm and 80 pm. A metallic coating can also be applied to other materials, such as the discs or other thermoplastic films.

[0032] According to one embodiment of the invention, the colored layer can comprise the entire surface of the first disk, the second disk, or the interconnected structure. This is advantageous because the coating is also frequently present over an area of ​​this size.

[0033] According to one embodiment of the invention, the composite structure can include the colored layer. This is advantageous because, for example, a thermoplastic layer of the composite structure can be the colored layer. In this case, this thermoplastic layer can, for example, fulfill several functions. However, it is also advantageous if another layer or film of the composite structure includes the colored layer, since this can be integrated into the composite structure particularly easily during the production of the composite disc.

[0034] According to one embodiment of the invention, the compound structure can comprise a thermoplastic film, which is the colored layer. The thermoplastic film can, for example, be based on polyvinyl butyral (PVB) or ethylene-vinyl acetate (SAINT-GOBAIN SEKURIT FRANCE 2024327-WO-PCT).

[0035] 6

[0036] (EVA) or polyurethane (PU) or from mixtures or copolymers or derivatives thereof, particularly preferably based on PVB.

[0037] According to one embodiment of the invention, the composite structure can comprise two thermoplastic films. A polyethylene terephthalate film can be arranged between the two thermoplastic films. The polyethylene terephthalate film can be the colored layer. Preferably, the polyethylene terephthalate film has a thickness of less than 100 pm, particularly preferably between 40 and 60 pm. The two thermoplastic films can be based, for example, on polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), or polyurethane (PU), or on mixtures or copolymers or derivatives thereof, particularly preferably on PVB.

[0038] According to one embodiment of the invention, the first and / or the second disc can be the colored layer. For example, the first and / or the second disc can be tinted and / or contain colored particles. In this embodiment, it is advantageous that no further element is required to incorporate the colored layer.

[0039] According to one embodiment of the invention, the light striking the second pane directly can be completely or partially p-polarized. This is particularly advantageous because the p-polarized light, or the p-polarized component of the light, is hardly or not at all reflected by the external glass surfaces of the laminated pane. The coating, however, is capable of reflecting the p-polarized radiation to display the information. Since there is thus only a single significant plane of reflection, namely the coating, the information is particularly visible. The use of p-polarized radiation is especially advantageous because it can penetrate sunglass lenses with polarizing filters.

[0040] According to one embodiment of the invention, the first pane can be an outer pane and the second pane an inner pane. For the purposes of this description, the outer pane is understood to be, in particular, a pane that faces outwards when the laminated pane is used as a windshield. For the purposes of this description, the inner pane is understood to be, in particular, a pane that faces towards the interior of the motor vehicle in this application. It is advantageous to apply the coating to the inner pane SAINT-GOBAIN SEKURIT FRANCE 2024327-WO-PCT

[0041] 7 is to be provided, as this results in fewer unwanted ghost images on reflective surfaces when projecting the information.

[0042] It is particularly advantageous to apply the coating to a surface of the inner window facing the interior of the motor vehicle, as this allows the information to be projected particularly clearly.

[0043] According to one embodiment of the invention, the composite glass, in particular as a windshield, can be designed for a motor vehicle. Projection devices are particularly frequently used in motor vehicles to project information onto a composite glass.

[0044] According to one embodiment of the invention, the coating can comprise a first layer, a second layer, and a third layer. The first layer can have a refractive index greater than 1.9. It can therefore be a high-refractive-index layer. The second layer can be based on a metal or a semiconductor. For example, in addition to the metal or semiconductor, the second layer can contain impurities of up to 5 wt.%. The third layer can have a refractive index of less than or equal to 1.6. It can therefore be a low-refractive-index layer. In particular, it is possible for the first and third layers to be dielectric layers. The second layer can be arranged between the first and third layers.Preferably, for example, the first single layer can be closer to the second disk than the third single layer.

[0045] Such a coating is particularly advantageous for the projection of information onto the composite disc, as is disclosed in particular in WO 2024 / 165281 A1.

[0046] It is also possible for the coating to comprise further individual layers. For example, the coating may comprise a fourth and a fifth individual layer. The fourth and fifth individual layers may, in particular, be dielectric. The fourth individual layer may have a refractive index of less than or equal to 1.6. The fifth individual layer may have a refractive index greater than or equal to 2.2. The fourth and fifth individual layers may be arranged between the first and second individual layers. In particular, it is possible for the fourth individual layer to be arranged between the first and fifth individual layers. SAINT-GOBAIN SEKURIT FRANCE 2024327-WO-PCT

[0047] 8

[0048] The display system for a motor vehicle according to claim 12 comprises a laminated glass panel according to an embodiment of the invention and a projection arrangement. The projection arrangement is configured to emit polarized light to the coating. This can particularly mean that the projection arrangement is arranged such that it emits polarized light to the coating. Preferably, the polarized light is emitted onto the coating at an angle of incidence between 45° and 70°, more preferably between 60° and 70°, for example, about 65°. These angles of incidence deviate only slightly from the Brewster angle. The Brewster angle for an air-glass interface in the case of soda-lime glass, which is commonly used for window panes, is 57.2° (with a refractive index of soda-lime glass of 1.55 at a wavelength of 550 nm).Since the angle of incidence typically does not deviate significantly from Brewster's angle, p-polarized radiation is generally not reflected, or only to a very small extent, by the external surfaces of the windshield (outer surface of the outer pane and inner surface of the inner pane). Reflection at the inner surface of the inner pane is practically solely due to the reflective coating.

[0049] The motor vehicle according to claim 13 comprises a display system according to an embodiment of the invention.

[0050] According to one embodiment of the invention, the composite glass can be a windshield of the motor vehicle.

[0051] Further features and advantages of the present invention will become clear with reference to the following description of preferred embodiments and the accompanying figures. The same reference numerals are used for identical or similar features and for features with identical or similar functions.

[0052] Fig. 1 shows a schematic sectional view of a composite disc according to an embodiment of the invention with a thermoplastic film as a colored layer;

[0053] Fig. 2 shows a schematic sectional view of a composite disc according to an embodiment of the invention with a polyethylene terephthalate film as a colored layer; SAINT-GOBAIN SEKURIT FRANCE 2024327-WO-PCT

[0054] 9

[0055] Fig. 3 is a schematic sectional view of a composite disc according to an embodiment of the invention with the first disc as the colored layer; and

[0056] Fig. 4 shows a schematic sectional view of a composite disc according to an embodiment of the invention with the second disc as the colored layer.

[0057] The composite discs shown in Figures 1 and 2 each comprise a first disc 1 and a second disc 2, which are bonded together by a bonding structure. The bonding structure comprises a thermoplastic film 3, preferably based on PVB.

[0058] A coating 4 is arranged on each of the second disks 2. The coating 4 is configured to reflect p-polarized light that strikes the second disk 2 directly and to transmit light that passes through the first disk 1 and the interconnect structure to the second disk 2. The coating 4 can be configured, in particular, as described in WO 2024 / 165281 A1. Specifically, the coating 4 can comprise at least three individual layers, of which a first layer is a dielectric optically high-refractive-index layer with a refractive index of 1.9 or higher, a second layer is a metal- or semiconductor-based layer, and a third layer is a dielectric optically high-refractive-index layer with a refractive index of 1.6 or less. This coating 4 has a slightly yellowish appearance, which may impair the overall optical appearance of the composite disk.

[0059] In the laminated glass pane shown in Figure 1, a thermoplastic film is therefore a colored layer 5, which is green-blue, blue, or green. The colored layer 5, like the coating 4, covers the entire surface of the second pane 2, so that the yellow tint of the laminated glass is at least partially compensated for. This makes the overall visual appearance of the laminated glass more harmonious.

[0060] In the laminated glass pane shown in Figure 2, a polyethylene terephthalate film is arranged between two thermoplastic films 3, which are preferably PVB films. The polyethylene terephthalate film, like the coating 4, covers the entire second pane 2. The polyethylene terephthalate film is the colored layer 6 and has a similar optical effect to the colored layer 5 in the laminated glass pane from Figure 1. The overall optical impression of the laminated glass pane in Figure 2 is also more harmonious, since the green, blue, or SAINT-GOBAIN SEKURIT FRANCE 2024327-WO-PCT

[0061] 10 green-blue polyethylene terephthalate film at least partially compensates for the yellow color of coating 4.

[0062] In the composite pane shown in Figure 3, the first pane is the colored layer 7. The colored layer 7, like the coating 4, extends over the entire surface of the second pane 2. The coating 4 and the colored layer 7 overlap each other. The colored layer 7 has a similar visual effect to the colored layers 5 and 6 in the composite panes shown in Figures 1 and 2. Similarly, in the composite pane shown in Figure 3, the overall visual impression is more harmonious because the green, blue, or green-blue colored layer 7 at least partially compensates for the yellow color of the coating 4.

[0063] In the laminated pane shown in Figure 4, the second pane is the colored layer 7. The colored layer 7, like the coating 4, extends over the entire surface of the second pane 2. The coating 4 and the colored layer 7 overlap each other. The colored layer 7 has a similar effect to the colored layer 7 in the laminated pane shown in Figure 3. In the laminated pane shown in Figure 4, the overall visual impression is also more harmonious, since the green, blue, or green-blue colored layer 7 at least partially compensates for the yellow color of the coating 4.

[0064] The following values ​​were found to be particularly advantageous for the colored layer in practical tests:

[0065] As can be seen from Examples 1 to 7, the colored layers 5, 6 and 7 preferably have a green, blue or green-blue color, so that the yellowish coloration of the coating 4 is at least partially compensated. SAINT-GOBAIN SEKURIT FRANCE 2024327-WO-PCT

[0066] 11

[0067] Preferably, the laminated glass panes shown in Figures 1 to 4 are used as windshields in a motor vehicle. The second pane 2 preferably faces an interior area of ​​the motor vehicle. The coating 4 is preferably arranged on the interior-facing surface of the second pane 2.

[0068] SAINT-GOBAIN SEKURIT FRANCE 2024327-WO-PCT

[0069] 12

[0070] Reference symbol list

[0071] 1 First disc

[0072] 2 Second disc 3 Thermoplastic film

[0073] 4 coating

[0074] 5 colored layers

[0075] 6 colored layers

[0076] 7 colored layers

Claims

SAINT-GOBAIN SEKURIT FRANCE 2024327-WO-PCT 13 Patent claims 1. Composite disk comprising a first disk (1 ; 7), a second disk (2; 7) and a connection structure (3; 5; 6), wherein the first disk (1; 7) is connected to the second disk (2; 7) via the connection structure (3; 5; 6), wherein the second disk (2; 7) has a coating (4), wherein the coating (4) is configured to reflect polarized light incident directly on the second disk (2; 7) and to transmit light incident through the first disk (1; 7) and the connection structure (3; 5; 6) to the second disk (2; 7), wherein the composite disk has a colored layer (5; 6; 7) comprises, characterized in that the colored layer (5; 6; 7) in the L*a*b* color space has an L* value between 70 and 100, in particular between 80 and 100, an a* value between -20 and 0, in particular between -10 and 0, and a b* value between -20 and 10, in particular between -10 and 10, wherein the colored layer (5; 6; 7) is configured to reflect infrared light to a proportion of more than 20%, preferably more than 50%.

2. Composite disc according to claim 1, characterized in that the colored layer (5; 6; 7) comprises a complete surface of the first disc (1), the second disc (2) or the connection structure (3; 5; 6).

3. Composite disc according to one of the preceding claims, characterized in that the connection structure (3; 5; 6) includes the colored layer (5; 6) includes.

4. Composite disc according to the previous claim, characterized in that the connection structure (3; 5; 6) comprises a thermoplastic film (3) which is the colored layer.

5. Composite disc according to claim 3, characterized in that the connection structure (3; 5; 6) comprises two thermoplastic films (3), wherein a polyethylene terephthalate film (6) is arranged between the two thermoplastic films (3), wherein the polyethylene terephthalate film (6) is the colored layer. SAINT-GOBAIN SEKURIT FRANCE 2024327-WO-PCT 14 6. Composite disc according to one of claims 1 or 2, characterized in that the first disc (1 ; 7) and / or the second disc (2; 7) is the colored layer (7).

7. Composite disc according to one of the preceding claims, characterized in that the light directly incident on the second disc (2; 7) is partially or completely p-polarized.

8. Composite disc according to one of the preceding claims, characterized in that the first disc (1 ; 7) is an outer disc and the second disc (2; 7) is an inner disc.

9. Composite disc according to one of the preceding claims, characterized in that the composite disc is designed for a motor vehicle.

10. Composite disc according to one of the preceding claims, characterized in that the coating (4) comprises a first single layer, a second single layer and a third single layer, wherein the first single layer has a refractive index greater than 1.9, wherein the second single layer is based on a metal or a semiconductor, and wherein the third single layer has a refractive index of less than or equal to 1.6, wherein the second single layer is arranged between the first single layer and the third single layer.

11. Display system for a motor vehicle, comprising a composite screen according to one of the preceding claims and a projection arrangement, wherein the projection arrangement is configured to emit the polarized light for coating.

12. Motor vehicle comprising a display system according to the preceding claim.

13. Motor vehicle according to the previous claim, characterized in that the composite window is a windscreen of the motor vehicle.

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