Composite pane with a colour-imparting coating
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- SAINT GOBAIN VITRAGE SA
- Filing Date
- 2026-01-09
- Publication Date
- 2026-08-06
Smart Images
Figure EP2026050365_06082026_PF_FP_ABST
Abstract
Description
[0001] SAI NT-GOBAI N GLASS FRANCE 2025016-WO-PCT
[0002] Composite disc with a color-imparting coating
[0003] The invention relates to a composite disc with a color-imparting coating and its use.
[0004] When designing buildings, architects often prioritize a specific external appearance, particularly a particular color impression that should be as consistent as possible from any viewing angle. Glazing elements frequently present a challenge in this regard. This is especially true when the glazing elements fulfill a function that limits design possibilities. For example, facade elements with integrated solar cells, designed as laminated glass, are increasingly being used. Such a laminated glass consists of an outer pane and an inner pane bonded together by a thermoplastic interlayer, within which the solar cells are embedded.The use of a colored outer pane to conceal the solar cells and ensure a desired color impression is often not possible or desired because it would limit the efficiency of the solar cells due to its light absorption and / or IR absorption.
[0005] From WO2018154045A1, a glass pane is known that has a satin-finished surface coated with a color-imparting layer. The coating consists of a sequence of individual layers with different refractive indices. The color-imparting layer forms a type of optical reflection filter with a spectral characteristic that ensures a reflection color with low dependence on the viewing angle. The glass pane is particularly suitable for encasing integrated solar cells without reducing their efficiency and yield. The color-imparting layer generates a reflection band in the visible spectral range, which represents a higher harmonic of the actual main reflection band. However, this requires comparatively thick individual layers, which are difficult to produce with conventional industrial coating equipment and / or are associated with high manufacturing costs.
[0006] From US2015249424A1, another glass pane with a color-imparting coating is known, which is suitable for laminating integrated solar cells. The glass pane has a satin-finished surface, whereby in this case the opposite surface is provided with the color-imparting coating. The coating is a consequence of SAI NT-GOBAI N GLASS FRANCE 2025016- WO-PCT
[0007] Thin films of dielectric oxides with different refractive indices, the exact layer sequence not being disclosed.
[0008] From WO2015155357A1, another glass pane with a color-imparting coating is known, which is suitable for laminating integrated solar cells. The glass pane has a satin-finished surface provided with the color-imparting coating. The coating is a sequence of relatively thin individual layers with different refractive indices, whereby a large number of alternating optically high and optically low refractive indices are required to generate the desired spectral characteristics, which is technically complex.
[0009] The use of glass panes with a specific reflective color is not limited to the outer panes of glazing elements with integrated solar cells. For example, so-called solar control glazing and low-E glazing are also conceivable. These are equipped with IR-reflective solar control coatings or low-E coatings to reduce thermal energy input, respectively, and the reflective color of these solar control coatings is intended to be concealed or homogenized by the outer pane.
[0010] EP3599647A1 discloses a solar module designed as a composite disc with a photovoltaic layer structure. The outer pane of the composite disc has an outer surface facing away from the intermediate layer, which is satin-finished and coated with an interference coating. In one embodiment, the interference coating consists of a first optically high-refractive-index layer of titanium oxide with a thickness of 65 nm, an optically low-refractive-index layer of silicon oxide with a thickness of 115 nm, and a second optically high-refractive-index layer of titanium oxide with a thickness of 65 nm.
[0011] US2024343638A1 discloses a vehicle roof window comprising a glass pane whose interior surface has a coating which, in addition to optically high-refractive-index and low-refractive-index dielectric layers for anti-reflection purposes, includes a metallic absorption layer.
[0012] The present invention is based on the objective of providing a composite glass pane with an improved color-imparting coating. The coating is intended to be SAI NT-GOBAI N GLASS FRANCE 2025016- WO-PCT
[0013] The design should allow for adjustment of the reflection color and be easy to manufacture, for which it should be achievable through a comparatively small number of alternating optically high-refractive-index and optically low-refractive-index layer modules (i.e., layers or layer sequences), whereby the individual layer modules should have a comparatively small thickness.
[0014] The problem is solved by a composite disk according to independent claim 1. Preferred embodiments are set forth in the dependent claims.
[0015] The composite pane according to the invention comprises a glass pane and another pane, which are bonded together via a thermoplastic interlayer. The glass pane is, in particular, the outer pane of the composite pane, and the other pane is the inner pane. The outer pane is the pane of the composite pane that, in its installed position, faces the external environment; the inner pane, correspondingly, faces away from the external environment.
[0016] The glass pane comprises at least one glass substrate and a color-imparting coating. The substrate is, in particular, a plate- or disc-like glass object and has a first surface (main surface) and a second surface (main surface) as well as an intermediate edge surface. The two main surfaces are, in particular, arranged substantially parallel to each other. The second surface of the substrate is satin-finished. The satin-finished second surface of the substrate is provided with the color-imparting coating. Starting from the second surface, the color-imparting coating according to the invention comprises, in the following order:
[0017] - a first optically high-refractive-index layer or layer sequence with a refractive index of more than 1.9 and an optical thickness of less than 200 nm,
[0018] - an optically low refractive index layer or sequence of layers with a refractive index of less than 1.6 and an optical thickness of less than 250 nm,
[0019] - a second optically high-refractive layer or sequence of layers with a refractive index of more than 1.9 and an optical thickness of less than 200 nm.
[0020] The satin-finished second surface of the glass pane (more precisely, the substrate of the glass pane), which is coated with the color-imparting layer, faces the intermediate layer – it is therefore primarily the interior surface of the outer pane. SAINT-GOBAIN GLASS FRANCE 2025016- WO-PCT
[0021] The color-imparting coating according to the invention is a sequence of a first optically high-refractive-index layer module, a first optically low-refractive-index layer module, and a second optically high-refractive-index layer module. The layer modules are each formed independently of one another, either as a single layer or as a sequence of layers. The reflection spectrum is generated by optical interference effects resulting from the sequence of the high-refractive-index and low-refractive-index layer modules. The color-imparting coating thus gives the composite panel a reflection color that can be specifically adjusted to the requirements of the particular application by modifying the design of the layer modules. The satin-finished surface has a type of surface texturing or roughening – the surface is therefore not smooth, but rather has sections arranged at an angle to one another.This means that the effective viewing angle is largely independent of the direction from which the viewer looks at the composite panel (actual viewing angle). This ensures that the reflected color is largely independent of the viewing angle.
[0022] The color-imparting coating according to the invention requires only three layer modules, which are also comparatively thin. This makes the glass pane simple and cost-effective to manufacture, using standard industrial coating equipment. By arranging the color-imparting coating on the surface of the glass pane facing the intermediate layer, the coating is effectively embedded within the laminated pane and protected from degradation due to environmental influences. These are significant advantages of the glass pane according to the invention.
[0023] The satin-finished second surface is roughened and thus appears cloudy, so that the substrate is translucent but opaque (frosted glass, colloquially also called "milk glass"). This applies to the substrate itself; as part of the laminated glass pane according to the invention, the satin-finished second surface is in contact with a thermoplastic intermediate layer, which at least partially eliminates the cloudiness and allows the glass pane to appear clear. The glass substrate with the satin-finished surface can be produced from a transparent glass substrate (especially clear glass) by roughening the surface, for example, by laser processing, sandblasting, grinding, screen printing, or treatment with hydrofluoric acid (etching). In sandblasting, the glass can be blasted with sand. However, for health reasons, fine corundum grains are typically used for blasting ("blasting corundum").Blasting corundum is SAI NT-GOBAI N GLASS FRANCE 2025016- WO-PCT.
[0024] A synthetic, mineral blasting abrasive is produced from high-quality bauxite or alumina melted in an electric arc furnace at over 2000 °C. It is also used in the manufacture of grinding wheels and sandpaper. Abrasive corundum is non-hygroscopic. By selecting different grain sizes, varying degrees of roughness can be achieved, thus offering different design possibilities. Glass sheets with a satin finish are also commercially available and can be purchased as glass substrates. Preferably, the second surface is fully satin-finished, meaning the entire second surface is satin-finished. However, it is optional to leave a border area unfinished.
[0025] The first surface of the glass pane (more precisely, the substrate of the glass pane) is preferably not satin-finished. It is therefore designed as a conventional smooth glass surface. In particular, it is the outer surface of the outer pane of the laminated glass unit. Dirt cannot accumulate as easily on the smooth surface as on a satin-finished one. This design therefore has the advantage that the first surface becomes less soiled during use, thus promoting high light transmission and reducing cleaning effort.
[0026] The color-imparting coating is preferably applied across the entire surface of the second substrate, thus covering the entire surface. However, it is also conceivable, for example, that a surrounding edge area of the surface is not coated with the color-imparting coating. This may be particularly desirable if said edge area is not visible in the installed position, but is covered, for example, by a frame element or a bracket. Preferably, however, at least 80%, and particularly preferably at least 90%, of the second surface is coated with the color-imparting coating.
[0027] The composite pane according to the invention is particularly intended or designed as a window pane or facade element of a building or building-like structure, or as a component of such a window pane or facade element. Alternatively, the composite pane according to the invention can also be intended or designed as a window pane of a vehicle (vehicle window), particularly as a roof pane of a motor vehicle. A window pane is intended to separate an interior space from the external environment within a window opening. A facade element is attached externally to the building. SAI NT-GOBAI N GLASS FRANCE 2025016- WO-PCT
[0028] For example, as cladding for a steel structure or concrete wall. The glass pane is preferably oriented towards and exposed to the external environment of the building (or vehicle). The glass pane thus preferably forms the outer pane of the laminated glass according to the invention. The substrate has an outer and an inner surface. For the purposes of the invention, the outer surface is defined as the main surface intended to face the external environment when installed. The inner surface is defined as the main surface intended to face the interior when installed. The satin-finished second surface of the substrate is preferably the inner surface, which faces away from the external environment.
[0029] The optically high-refractive-index layer modules have a refractive index greater than 1.9, for example, between 1.9 and 3.0, preferably at least 2.0, for example, from 2.0 to 2.5. The optically low-refractive-index layer module has a refractive index less than 1.6, for example, between 1.0 and 1.6, preferably at most 1.5, for example, from 1.2 to 1.5. This means that each individual layer of the respective layer module has the aforementioned refractive index. The optically high-refractive-index layer modules are therefore formed from a single layer with a refractive index greater than 1.9 or from a sequence of layers, wherein all layers of the sequence each have a refractive index greater than 1.9.Similarly, the optically low refractive index layer modulus is formed from a single layer with a refractive index of less than 1.6 or from a sequence of layers, wherein all layers of the sequence each have a refractive index of less than 1.6.
[0030] Refractive indices are generally specified within the scope of the present invention with reference to a wavelength of 550 nm. The refractive index is fundamentally independent of the measurement method. It can, for example, be determined by ellipsometry. Ellipsometers are commercially available, for example from Sentech.
[0031] The layer modules are designed as dielectric layers or layer sequences. The color-imparting coating therefore contains no electrically conductive layers (for example, based on metals or transparent conductive oxides) – it is a purely dielectric coating. The dielectric layers may contain dopants, in particular aluminum, boron, antimony, zirconium, hafnium, or titanium. Through doping, inherently dielectric materials can be transformed into materials with a certain electrical conductivity. SAINT-GOBAIN GLASS FRANCE 2025016- WO-PCT
[0032] They are provided with conductivity. However, those skilled in the art will identify them as dielectric layers with regard to their function, as is common in the field of thin films. The material of the dielectric layers preferably has an electrical conductivity (inverse of the resistivity) of less than 10⁻⁶. 4 S / m, especially smaller than 10' 8S / m. The conductivity can be determined, for example, by measuring the sheet resistance using a 4-point resistance measurement, such as with the NAGY SD-600 Sheet Resistivity Meter. The doping concentration is preferably less than 30 wt.%, particularly preferably less than 10 wt.%.
[0033] The first high-refractive-index layer module is preferably the lowest layer module of the coloring coating and is preferably applied directly to the satin-finished second surface of the substrate. The low-refractive-index layer module is preferably arranged directly on top of the first high-refractive-index layer module. The second high-refractive-index layer module is preferably arranged directly on top of the low-refractive-index layer module. The second high-refractive-index layer module is particularly preferably the uppermost layer module of the coloring coating. The coloring coating particularly preferably consists only of the two high-refractive-index layer modules and the low-refractive-index layer module between them and has no further layers or layer modules.
[0034] With regard to the layers and layer modules of the color-imparting coating, relative terms such as "above," "below," "above," "below," "top," and "bottom" are always given in relation to the order starting from the second surface of the substrate. A first layer located below or beneath a second layer has a smaller distance to the second surface than the second layer. A first layer located above, on top of, or above a second layer has a greater distance to the second surface than the second layer. The bottommost layer module has the smallest distance of all layer modules to the second surface, and the topmost layer module has the greatest distance.If a layer or layer module is arranged directly on, above, over, below, or under another layer or layer module, with no further layers in between, so that the two layers or layer modules are in direct contact with each other. SAI NT-GOBAI N GLASS FRANCE 2025016- WO-PCT.
[0035] The optical thickness of a layer according to the present invention is the product of the geometric thickness and the refractive index at 550 nm. If the optical thickness is meant, this is always explicitly stated. Otherwise, specifications regarding layer thickness or thickness always refer to the geometric thickness.
[0036] According to the invention, the first optically high-refractive index layer module (first optically high-refractive index layer or layer sequence) has an optical thickness of less than 200 nm, in particular from 20 nm to 200 nm. In an advantageous embodiment, the first optically high-refractive index layer module has an optical thickness of less than 150 nm, preferably from 20 nm to 150 nm, particularly preferably from 50 nm to 150 nm, and most preferably from 80 nm to 150 nm. This results in particularly good results.
[0037] According to the invention, the optically low refractive index layer modulus (optically low refractive index layer or layer sequence) has an optical thickness of less than 250 nm, in particular from 20 nm to 250 nm. In an advantageous embodiment, the optically low refractive index layer modulus has an optical thickness of less than 200 nm, preferably from 20 nm to 200 nm, particularly preferably from 50 nm to 200 nm, and most preferably from 70 nm to 200 nm. This results in particularly good results.
[0038] According to the invention, the second optically high-refractive-index layer module (second optically high-refractive-index layer or layer sequence) has an optical thickness of less than 200 nm, in particular from 20 nm to 200 nm. In an advantageous embodiment, the second optically high-refractive-index layer module has an optical thickness of less than 150 nm, preferably from 20 nm to 150 nm, particularly preferably from 50 nm to 150 nm, and most preferably from 80 nm to 150 nm. This results in particularly good results.
[0039] The first optically high-refractive-index layer module and the second optically high-refractive-index layer module preferably each comprise, independently of one another, one or more dielectric layers based on titanium oxide, silicon nitride, silicon-metal mixed nitride, tungsten oxide, zinc oxide, niobium oxide, aluminum nitride, bismuth oxide, tantalum oxide, hafnium oxide, chromium oxide, tin oxide, zirconium oxide, titanium zirconium oxide, silicon zirconium oxide, hafnium oxide, or tin-zinc oxide. Titanium oxide, silicon nitride (especially aluminum-doped silicon nitride), zinc oxide, tin-zinc oxide, and silicon-metal mixed nitride (especially silicon zirconium nitride, silicon hafnium nitride, or silicon titanium nitride) are particularly preferred due to their suitable refractive index and good availability. SAINT-GOBAIN GLASS FRANCE 2025016- WO-PCT
[0040] and good deposition rates. It is particularly preferred that the optically high-refractive-index layer modules comprise exclusively layers of the aforementioned materials, and no further layers of other materials.
[0041] If a layer of the color-imparting coating is based on a material, the layer consists predominantly of this material (at least 50 wt.%), and in particular essentially of this material alongside any impurities or dopants. The proportion of the material is preferably at least 80 wt.%, and in particular at least 90 wt.%.
[0042] In an advantageous embodiment, the first and second optically high-refractive-index layer modules are each formed as a sequence of several individual layers, wherein the individual layers preferably each have a thickness of at most 80 nm, and particularly preferably at most 50 nm. By dividing the total thickness of the layer modules into several, each thinner, individual layers, higher line speeds can be achieved in typical industrial coating systems, and the coating can consequently be deposited more quickly. In particular, the individual layers can be applied in successive chambers of a coating system, and by dividing the module into individual layers, each chamber is available for coating the next substrate sooner than if the entire layer module were deposited as a thicker single layer in a single chamber with a single target.Directly successive individual layers of each layer module are preferably made of different materials.
[0043] In an advantageous embodiment, the second optically high-refractive-index layer module is formed as a sequence of several individual layers and comprises, as the uppermost layer, a thin topcoat based on titanium oxide, zirconium oxide, titanium-zirconium oxide, silicon-zirconium oxide, or hafnium oxide. Titanium oxide is preferred. The topcoat serves to improve scratch resistance and / or abrasion resistance. The topcoat preferably has a thickness of 1 nm to 10 nm, particularly preferably 2 nm to 5 nm. The topcoat is, in particular, the uppermost layer of the color-imparting coating and is exposed to the environment—that is, no further layers or other components of the glass pane are arranged above the topcoat. SAI NT-GOBAI N GLASS FRANCE 2025016- WO-PCT
[0044] The optically low refractive index layer preferably comprises one or more dielectric layers based on silicon oxide, nanoporous silicon oxide, magnesium fluoride, or calcium fluoride. Particularly preferably, the optically low refractive index layer comprises only a single silicon oxide-based layer due to its suitable refractive index, good availability, and mechanical stability.
[0045] According to the invention, the substrate of the glass pane is made of glass, preferably soda-lime glass, as is common for window panes. However, the substrate can also be made of other types of glass, such as quartz glass, borosilicate glass, or aluminosilicate glass. The glass is preferably clear, i.e., without any tints or colors. The integrated light transmission of the substrate, measured with a standard D65 light source, is preferably at least 85% in the visible spectral range from 380 nm to 780 nm, based on a substrate thickness of 4 mm. However, it is also possible for the substrate to have a slight tint or color, in which case the light transmission should preferably be no less than 70%. The thickness of the substrate can be selected to suit the requirements of the individual case. Thicknesses of 0.5 mm to 12 mm are particularly common, preferably 1 mm to 10 mm, and most preferably 2 mm to 8 mm.
[0046] The laminated glass can be flat (as is common in building glazing and glazing of buses or trucks) or curved (for example as glazing of modern high-rise buildings or as a vehicle window, especially for passenger cars).
[0047] The thermoplastic interlayer contains at least one thermoplastic polymer, preferably ethylene vinyl acetate (EVA), polyvinyl butyral (PVB), or polyurethane (PU), or mixtures, copolymers, or derivatives thereof, particularly preferably PVB. The interlayer is typically formed from at least one thermoplastic film (bonding film), particularly based on PVB, EVA, or PU, preferably PVB. This means that the film consists largely of the aforementioned polymer (proportion greater than 50 wt.%). In addition to the polymer, the film may contain other additives, such as plasticizers, stabilizers, or UV or IR absorbers. The thickness of each thermoplastic film is preferably from 0.2 mm to 2 mm, particularly preferably from 0.3 mm to 1 mm. For example, films, especially PVB films, with standard thicknesses of 0.38 mm or 0.76 mm can be used. SAI NT-GOBAI N GLASS FRANCE 2025016- WO-PCT
[0048] The second pane is also preferably made of glass, in particular soda-lime glass. It preferably has a thickness of 0.5 mm to 12 mm, particularly preferably 1 mm to 10 mm, and most preferably 2 mm to 8 mm.
[0049] The laminated pane can be used as a window pane in a building or vehicle, or as a facade element of a building. Alternatively, the laminated pane can be part of an insulating glass unit, where it is connected to another pane via a frame-like spacer, creating a cavity between the laminated pane and the other pane. The insulating glass unit can then be used as a window pane or facade element of a building. The cavity is typically filled with an inert gas. The thermal conductivity is reduced by the space between the panes. The spacer typically has a cavity filled with a desiccant to keep the cavity between the panes free of moisture.
[0050] In a first preferred embodiment of the laminated pane, the second pane is provided with an IR-reflective coating. Such a laminated pane can be used, for example, as a window pane with solar control or thermal insulation properties, or as a component thereof. Its use as a window pane is possible despite the satin-finished second surface because the intermediate layer in contact with it makes the second surface clear again. Typical IR-reflective coatings exhibit a reflection color that is usually dependent on the viewing angle. The color-imparting coating according to the invention can mask or compensate for this, and in particular, ensure an angle-independent color impression. IR-reflective coatings are commonly used in both building and vehicle glazing.
[0051] The IR-reflective coating can be a solar control coating or an emissivity-reducing coating (Low-E coating). It is also possible that the other pane is equipped with both a solar control coating and a Low-E coating.
[0052] A solar control coating is an IR-reflective coating that can reflect the infrared components of sunlight in particular. This can increase the thermal comfort of an interior space enclosed by the laminated glass. SAI NT-GOBAI N GLASS FRANCE 2025016- WO-PCT
[0053] which heats up less. The solar control coating is preferably a thin-film stack, i.e., a sequence of thin individual layers. Preferably, the solar control coating comprises at least one electrically conductive layer, which is primarily responsible for the IR-reflective effect. The electrically conductive layer is preferably a metal-based layer, particularly preferably silver-based. Dielectric layers or sequences of layers are typically arranged above and below the electrically conductive layer. If the solar control coating comprises several conductive layers, each conductive layer is preferably arranged between two typically dielectric layers or sequences of layers, so that a dielectric layer or sequence of layers is arranged between adjacent conductive layers.The coating is therefore a thin-film stack with n electrically conductive layers and (n+1) dielectric layers or sequences of layers, where n is a natural number and where a conductive layer and a dielectric layer or sequence of layers alternately follow each lower dielectric layer or sequence.
[0054] The conductive layer preferably contains at least 90 wt.% silver, particularly preferably at least 99 wt.% silver, and most preferably at least 99.9 wt.% silver. The silver layer may contain dopants, for example, palladium, gold, copper, or aluminum. The thickness of the silver layer is typically from 5 nm to 20 nm.
[0055] Examples of common dielectric layers in such a thin-film stack are:
[0056] Anti-reflective coatings, which reduce the reflection of visible light and thus increase the transparency of the coated disc, for example based on silicon nitride, silicon-metal mixed nitrides such as silicon zirconium nitride, titanium oxide, aluminum nitride or tin oxide, with layer thicknesses of, for example, 10 nm to 100 nm;
[0057] Matching layers that improve the crystallinity of the electrically conductive layer, for example based on zinc oxide (ZnO), with layer thicknesses of, for example, 3 nm to 20 nm;
[0058] Smoothing layers that improve the surface structure for the layers above, for example based on a non-crystalline oxide of tin, silicon, titanium, zirconium, hafnium, zinc, gallium and / or indium, in particular based on tin-zinc mixed oxide (ZnSnO), with layer thicknesses of, for example, 3 nm to 20 nm.
[0059] The solar control coating can include, in addition to electrically conductive and dielectric layers, blocker layers which protect the conductive layers. SAINT-GOBAIN GLASS FRANCE 2025016- WO-PCT
[0060] To protect against degradation. Blocker layers are typically very thin metal-containing layers based on niobium, titanium, nickel, chromium and / or alloys with layer thicknesses of, for example, 0.1 nm to 2 nm.
[0061] However, solar control coatings do not necessarily have to include electrically conductive layers. Purely dielectric solar control coatings are also known, which consist of alternating layers with high and low refractive indices. By appropriately selecting the materials and layer thicknesses, the reflection behavior of such a layer sequence can be specifically controlled due to interference effects.
[0062] The solar control coating can be applied to the surface of the second pane facing the interlayer, where it is protected within the laminated glass unit. This is particularly important to consider if the solar control coating is susceptible to corrosion (for example, due to a conductive metallic layer, especially a silver layer). The solar control coating can also be applied to the surface of the second pane facing away from the interlayer, especially if the laminated glass unit is part of an insulating glass unit and this surface faces the cavity of the insulating glass unit. In this case, the solar control coating is also protected there.
[0063] An emissivity-reducing coating is an IR-reflective coating that reflects heat radiation. Such coatings are also known as heat-radiation-reflective coatings, low-emissivity coatings, or LowE (low emissivity) coatings. Emissivity is the measure that indicates how much heat radiation the laminated glass pane emits into an interior space compared to an ideal heat radiator (a black body). Emissivity-reducing coatings serve to decrease the amount of heat entering the interior space (IR components of solar radiation and, in particular, the thermal radiation from the pane itself) and also the heat radiated out of the interior space. They exhibit reflective properties towards infrared radiation, especially heat radiation in the spectral range of 5 pm to 50 pm (see also standard DIN EN 12898:2019-06).This effectively improves thermal comfort in the interior. SAI NT-GOBAI N GLASS FRANCE 2025016- WO-PCT.
[0064] The emissivity-reducing coating is typically a transparent stack of thin films. The emissivity-reducing coating preferably comprises at least one, and more preferably exactly one, electrically conductive layer, which provides the IR-reflective properties. The conductive layer is preferably based on a transparent conductive oxide (TCO), in particular indium tin oxide (ITO), or alternatively, for example, indium zinc mixed oxide (IZO), gallium-doped tin oxide (GZO), fluorine-doped tin oxide (FTO, SnO₂:F), antimony-doped tin oxide (ATO, SnO₂:Sb), or niobium-doped titanium oxide (TiÜ₂:Nb). Unlike metals, TCOs are not susceptible to corrosion, so they can be used on an exposed surface of the composite disk.In addition to the conductive layer, the coating typically includes dielectric layers (for example, based on silicon oxide or nitride), which serve in particular to optimize the optical properties (e.g., light transmission) or act as barrier layers to regulate oxygen diffusion during coating deposition. The electrically conductive layer is preferably based on ITO, which has proven particularly advantageous, especially due to its low resistivity and low scatter in sheet resistance. The thickness of the TCO layer ranges, for example, from 30 nm to 150 nm.
[0065] Typically, a dielectric layer or sequence of layers is arranged above and below the TCO layer, significantly influencing the optical properties, particularly transmission and reflectivity. The emissivity-reducing coating is also a thin-film stack, i.e., a sequence of thin individual layers. Common dielectric layers include, for example, anti-reflective coatings, barrier layers to control oxygen diffusion during the manufacturing of the glass pane, and blocker layers to prevent the diffusion of alkali ions from the glass pane into the coating.
[0066] The emissivity-reducing coating is preferably arranged on the surface of the further disc facing away from the intermediate layer, where it can fulfill its function particularly advantageously.
[0067] The IR-reflective coating is preferably applied across the entire surface of the glass, with the exception of any uncoated perimeter area. Optionally, further locally limited areas may also be left uncoated, designated as SAI NT-GOBAI N GLASS FRANCE 2025016- WO-PCT
[0068] Communication, sensor, or camera windows are intended to ensure the transmission of electromagnetic radiation through the laminated glass. Preferably, at least 80% of the relevant glass surface is provided with the IR-reflective coating.
[0069] In a second preferred embodiment of the laminated glass pane, at least one photovoltaic component is embedded in the intermediate layer. The photovoltaic component is arranged, in particular, between two thermoplastic layers (preferably films), being connected to the outer pane via one thermoplastic layer and to the inner pane via the other. Such a laminated glass pane can be used, for example, as a facade element or component thereof, with the photovoltaic component being laminated by the glass pane according to the invention, bearing the color-imparting coating, in particular ensuring an angle-independent color appearance. Alternatively, such a laminated glass pane can be used as a vehicle window, in particular as a roof window, which need not be transparent.
[0070] A photovoltaic component is an electrical component used to generate electrical energy or current by means of the photovoltaic effect. The photovoltaic component can also be referred to as a photovoltaic element, photovoltaic module, solar module, or solar element. The photovoltaic component has a photovoltaically active absorber layer between a front electrode and a back electrode. The front electrode faces the glass pane (outer pane) according to the invention, which has the color-imparting coating, while the back electrode faces the inner pane. The electrodes are, in particular, surface electrodes that cover the entire absorber layer.When sunlight is absorbed, free charge carriers are generated in the absorber layer (photovoltaic effect as a special case of the internal photoelectric effect), which are then carried away via the electrodes to generate electrical energy or an electric current. The absorber layer often contains dopants to optimize the transport of the charge carriers to the electrodes. The precise design of the photovoltaic component is irrelevant to the invention; all known photovoltaic components can be used.
[0071] The photovoltaic component preferably comprises a photovoltaically active layer (absorber layer) that absorbs in the visible spectral range. Such a photovoltaic component is typically opaque. SAINT-GOBAIN GLASS FRANCE 2025016- WO-PCT
[0072] The at least one photovoltaic component can optionally be surrounded by a further thermoplastic layer, which, for the purposes of the invention, is also referred to as a capsule layer. The capsule layer is preferably frame-shaped and arranged in a circumferential edge region of the composite panel, with the at least one photovoltaic component being inserted into the frame-shaped capsule layer. The capsule layer has at least one recess into which the at least one photovoltaic component is inserted. The capsule layer can be formed by a thermoplastic film into which the recess has been cut. Alternatively, the capsule layer can also be composed of several film sections surrounding the at least one photovoltaic component. The capsule layer preferably has approximately the same thickness as the at least one photovoltaic component.This compensates for the local thickness difference introduced by the locally limited at least one photovoltaic component, thus avoiding air inclusions, preventing glass breakage during lamination, and resulting in an improved optical appearance.
[0073] The invention also includes a method for producing a composite disc according to the invention, wherein the substrate with the satin-finished second surface is provided and the color-imparting coating is applied to the second surface.
[0074] The glass pane can be purchased with the satin finish already applied. Alternatively, the glass pane can initially be supplied with flat surfaces, and the second surface can be satin-finished separately, for example mechanically by sandblasting or grinding, or by chemical etching.
[0075] The coating is preferably deposited onto the substrate surface by vapor deposition, for example by chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PECVD), or atomic layer deposition (ALD). Physical vapor deposition (PVD), for example evaporation, is particularly preferred, especially sputtering and, in particular, magnetron sputtering. SAINT-GOBAIN GLASS FRANCE 2025016- WO-PCT
[0076] The composite pane according to the invention can be produced by bonding the coated glass pane and the other pane using conventional methods. The glass pane is bonded to the other pane via the thermoplastic interlayer. Lamination processes known per se are used for this purpose, for example, autoclave processes, vacuum bag processes, vacuum ring processes, calender processes, vacuum laminators, or combinations thereof. The bonding of the panes via the interlayer is typically carried out under the influence of heat, vacuum, and / or pressure.
[0077] The invention further comprises the use of a composite glass pane according to the invention as a window pane or facade element of a building or as a component thereof, or as a window pane of a vehicle (in particular a roof pane), as already described above. SAINT-GOBAIN GLASS FRANCE 2025016- WO-PCT
[0078] The invention is explained in more detail with reference to a drawing and exemplary embodiments. The drawing is a schematic representation and not to scale. The drawing does not limit the invention in any way. It shows:
[0079] Fig. 1 shows a cross-section through an embodiment of the composite disk according to the invention,
[0080] Fig. 2 is an enlarged view of section Z from Figure 1,
[0081] Fig. 3 shows a cross-section through a further embodiment of the composite disk according to the invention,
[0082] Fig. 4 shows a cross-section through a further embodiment of the composite disc according to the invention,
[0083] Fig. 5 Reflection spectra of composite disks V according to examples 1 to 4 and the comparison example.
[0084] Figures 1 and 2 each show a detail of a laminated glass pane V according to the invention. The laminated glass pane V comprises a glass pane 1, a thermoplastic interlayer 5, and a further pane 4. The glass pane 1 has a first surface I and a second surface II. The further pane 4 also has a first surface III and a second surface IV. The glass pane 1 is the outer pane of the laminated glass pane V, and the further pane 4 is the inner pane. Accordingly, the first surfaces I and III are the outer surfaces, and the second surfaces II and IV are the inner surfaces. The second surface II of the glass pane 1 is connected to the first surface III of the further pane 4 via the interlayer 5.
[0085] The glass pane 1 comprises a substrate 2 made of clear soda-lime glass with a thickness of, for example, 8 mm. The substrate 2 has two main surfaces, namely the first surface I and the second surface II, as well as a side edge surface extending between them.
[0086] The second pane 4 consists of soda-lime glass with a thickness of 8 mm. The thermoplastic interlayer 5 is formed by a PVB film with a thickness of 0.76 mm. SAI NT-GOBAI N GLASS FRANCE 2025016- WO-PCT
[0087] The laminated pane V can be used as a window pane in a building or as a component thereof, for example, when it is connected to another pane by a spacer to form insulating glass. The window pane separates the interior of a building from the outside environment. If the laminated pane V is connected to another pane to form insulating glass, this additional pane is positioned on the interior side of the laminated pane V and connected to the additional pane 4 via the spacer.
[0088] The second surface II of substrate 2 has a satin finish. It has a surface structure that makes substrate 2 appear matte or cloudy. A color coating 3 is applied to the second surface II. The color coating 3 consists of a first optically high refractive index layer or layer sequence 3.1 (first optically high refractive index layer modulus), an optically low refractive index layer or layer sequence 3.2 (optically low refractive index layer modulus), and a second optically high refractive index layer or layer sequence 3.3 (second optically high refractive index layer modulus). The layer modules are arranged on the second surface II in the specified order, starting from the second surface.
[0089] The optically high-refractive-index layers or layer sequences 3.1 and 3.3 each comprise a single layer or a plurality of layers with a refractive index greater than 1.9. The optically low-refractive-index layer or layer sequence 3.2 comprises a single layer or a plurality of layers with a refractive index less than 1.6. The optical thickness of the first optically high-refractive-index layer or layer sequence 3.1 is less than 200 nm, that of the optically low-refractive-index layer or layer sequence 3.2 is less than 250 nm, and that of the second optically high-refractive-index layer or layer sequence 3.3 is less than 200 nm.
[0090] The color-imparting coating 3, with its alternating arrangement of high-refractive-index and low-refractive-index layers or layer sequences 3.1, 3.2, 3.3, allows the reflection color of the glass pane 1 or the laminated pane V to be adjusted, with the reflection behavior being primarily due to optical interference effects. The color-imparting coating 3 is comparatively simple, consisting of only three relatively thin layer modules. It is therefore easy to manufacture. The satin-finished surface II ensures that the reflection color exhibits only a slight dependence on the viewing angle of the glass pane. SAINT-GOBAIN GLASS FRANCE 2025016- WO-PCT
[0091] 1. The colored coating allows for the adjustment of a desired reflection color, which is also independent of the viewing angle. This is aesthetically advantageous when the laminated pane V is used as glazing (window pane, facade element) of a building or as a component thereof. In particular, in further developments of the laminated pane V, the colored coating 3 can be used to conceal other elements of the glazing, for example, opaque elements such as photovoltaic components or solar control coatings, which sometimes exhibit an undesirable and strongly angle-dependent reflection color. These are significant advantages of the present invention.
[0092] Figure 3 shows a further development of the composite pane V according to the invention. The composite pane V again comprises the glass pane 1 (outer pane) with the substrate 2 and the color-imparting coating 3 on the satin-finished second surface II of the substrate 2, the further pane 4 (inner pane) and the thermoplastic intermediate layer 5. These components are designed in the same way as in the embodiment of Figure 1.
[0093] In contrast to Figure 1, the first surface III of the further disk 4 facing the intermediate layer 5 is provided with a solar control coating 8. The solar control coating 8 is a thin-film stack with at least one silver layer, which reflects IR components of the solar radiation.
[0094] The laminated glass unit V can be used as a window pane in a building or as a component thereof, for example, when connected to another pane by a spacer to form insulating glass. The colored coating allows for a uniform and angle-independent reflective color to be set, which is perceived by observers looking at the building from the outside. This effectively masks any color influence from the solar control coating 8.
[0095] Figure 4 shows a further embodiment of the laminated glass pane V according to the invention. The laminated glass pane V again comprises the glass pane 1 (outer pane) with the substrate 2 and the color-imparting coating 3 on the satin-finished second surface II of the substrate 2, the further pane 4 (inner pane), and the thermoplastic intermediate layer 5. The glass pane 1 and the further pane 4 are configured in the same way as in the embodiment shown in Figure 1. SAINT-GOBAIN GLASS FRANCE 2025016- WO-PCT
[0096] The thermoplastic intermediate layer 5 is formed by a first layer 5.1 and a second layer 5.2, each of which is made of a PVB film with a thickness of 0.76 mm, wherein a plurality of photovoltaic components 6 are embedded in the intermediate layer 5 between the thermoplastic layers 5.1, 5.2.
[0097] The composite panel V can be used as a facade element of a building (building cladding) or as a component thereof, for example, connected to another pane by a spacer to form insulating glass. The colored coating allows for a uniform and angle-independent reflective color, which is perceived by observers looking at the building from the outside. The opaque photovoltaic components 6 can be optically concealed so that they are not visually distracting.
[0098] Examples
[0099] Laminated glass panes V were produced from a substrate 2, which was made of clear soda-lime glass with a thickness of 6 mm, and another pane 4, which was made of clear soda-lime glass with a thickness of 2.1 mm. The substrate 2 was bonded to the second pane 4 via a thermoplastic interlayer 5, which was made of an opaque, black PVB film (0% light transmission) with a thickness of 0.76 mm. The opaque PVB film simulated the presence of opaque photovoltaic components in the interlayer 5. The second surface II of the substrate 2, facing the interlayer 5, was satin-finished and provided with a color coating 3. The substrate 2 with the color coating 3 thus formed a glass pane 1 according to the invention as a component of the laminated glass pane V according to the invention.
[0100] The structure of four examples 1 to 4 according to the invention is summarized in Table 1. The layer structure of the color-imparting coating 3 is also shown there. The optically high-refractive-index layers or layer sequences 3.1, 3.3 were each formed from a plurality of individual layers, while the optically low-refractive-index layer or layer sequence 3.2 was each formed from only a single layer. Examples 1 to 4 differed in the thickness of the individual layers and thus in the optical thickness of the layers or layer sequences 3.1, 3.2, 3.3. SAINT-GOBAIN GLASS FRANCE 2025016- WO-PCT
[0101] Table 1
[0102]
[0103] The refractive index (at 550 nm) of the silicon nitride (SisN^) based layers was 2.0, that of the silicon-zirconium mixed nitride (SiZrN) based layers was 2.0. x) 2.2, that of the titanium oxide (TiÜ2)-based layers 2.45, and that of the silicon oxide (SiÜ2)-based layers 1.45. The optical thicknesses of the layer modules are summarized in Table 2. The optical thicknesses of the layer modules are the sum of the optical thicknesses of the respective individual layers, which in turn are the product of the refractive index and the geometric layer thickness. SAINT-GOBAIN GLASS FRANCE 2025016- WO-PCT
[0104] Table 2
[0105]
[0106] Furthermore, a non-inventive composite disc V was produced as a comparative example. The comparative example differed from the examples according to the invention only in the structure of the color-imparting coating 3. The coating 3 consisted of a layer based on SisN4 with a thickness of 140 nm (optical thickness 280.0 nm).
[0107] a layer based on TiÜ2 with a thickness of 170 nm (optical thickness 416.5 nm),
[0108] a layer based on SisN4 with a thickness of 200 nm (optical thickness 400.0 nm),
[0109] a layer based on TiÜ2 with a thickness of 170 nm (optical thickness 416.5 nm),
[0110] a layer based on SisN4 with a thickness of 140 nm (optical thickness 280.0 nm) and
[0111] a layer based on SiÜ2 with a thickness of 140 nm (optical thickness 203.0 nm),
[0112] which were arranged in the specified order starting from the second surface II of substrate 2.
[0113] The coating of the comparative example was a color-imparting coating as proposed in WO2018154045A1. For the purposes of the present invention, the alternating layers based on SisN4 and TiÜ2 can be considered as an optically high-refractive-index layer sequence 3.1 with a total optical thickness of 1793.0 nm, and the upper layer based on SiÜ2 as an optically low-refractive-index layer 3.2 with an optical thickness of 203.0 nm. The comparative example differs from examples 1 to 4 according to the invention by the absence of the upper optically high-refractive-index layer or layer sequence 3.3 and by a significantly thicker lower optically high-refractive-index layer or layer sequence 3.1. SAINT-GOBAIN GLASS FRANCE 2025016- WO-PCT
[0114] Figure 5 shows reflection spectra of examples 1 to 4 and the comparative example. The samples were irradiated via the first surface I of the glass sheet 1 according to the invention (external reflection) with a light source that emits radiation with uniform intensity in the considered spectral range and an angle of incidence (measured to the surface normal) of 8°.
[0115] Examples 1 to 3 exhibit quite strong reflection, with the reflection band positioned differently. The colored coating 3 can therefore produce a distinct color impression, whereby the color (spectral position of the reflection band) can be adjusted by the optical thickness of the layer modules.
[0116] In example 4 with the significantly thinner layer modules, a reflection behavior is also achieved, but it is significantly less pronounced than in examples 1 to 3 (lower reflectance).
[0117] In the comparative example, a pronounced reflection band also appears, which is more selective (narrower) than in examples 1 to 4. However, this is not absolutely necessary for producing a color. The coating 3 with the very thick individual layers is significantly more complex to manufacture than the coating 3 of the examples according to the invention. SAINT-GOBAIN GLASS FRANCE 2025016- WO-PCT
[0118] Reference symbol list:
[0119] (1) glass pane
[0120] (2) substrate
[0121] (3) colouring coating
[0122] (3.1) first optically high refractive index layer or layer sequence of the coating 3 (3.2) optically low refractive index layer or layer sequence of the coating 3
[0123] (3.3) second optically high refractive layer or layer sequence of the coating 3 (4) further pane of a laminated pane V
[0124] (5) thermoplastic interlayer of a composite disc V
[0125] (5.1) first layer of the intermediate layer 5
[0126] (5.2) second layer of the intermediate layer 5
[0127] (6) photovoltaic component
[0128] (8) Sun protection coating
[0129] (V) Composite disc
[0130] (I) first surface of the substrate 2
[0131] (II) second surface of the substrate 2
[0132] (III) first surface of the next disk 4
[0133] (IV) second surface of the other disk 4
[0134] Z Enlarged area
Claims
26 SAI NT-GOBAI N GLASS FRANCE 2025016-WO-PCT Patent claims 1. Composite disc (V), comprising a glass pane (1) comprising a substrate (2) made of glass with a first surface (I) and a second surface (II) and a coloring coating (3), wherein at least the second surface (II) of the substrate (2) is satin-finished and provided with the coloring coating (3), another disc (4), wherein the glass pane (1) and the further pane (4) are connected to each other via a thermoplastic intermediate layer (5), wherein the second surface (II) of the glass pane (1) faces the intermediate layer (5), and wherein the color-imparting coating (3) starting from the second surface (II) in the specified order a first optically high-refractive-index layer or sequence of layers (3.1) with a refractive index of more than 1.9 and an optical thickness of less than 200 nm, an optically low refractive index layer or layer sequence (3.2) with a refractive index of less than 1.6 and an optical thickness of less than 250 nm, a second optically high-refractive layer or layer sequence (3.3) with a refractive index of more than 1.9 and an optical thickness of less than 200 nm includes and wherein the colouring coating (3) does not have any electrically conductive layers.
2. Composite pane (V) according to claim 1, wherein the first surface (I) of the glass pane (1) is not satin-finished.
3. Composite disc (V) according to claim 1 or 2, wherein the first optically high-refractive-index layer or layer sequence (3.1) has an optical thickness of less than 150 nm, preferably from 20 nm to 150 nm, particularly preferably from 50 nm to 150 nm, most preferably from 80 nm to 150 nm. SAINT-GOBAIN GLASS FRANCE 2025016- WO-PCT 4. Composite disk (V) according to any one of claims 1 to 3, wherein the optically low refractive index layer or layer sequence (3.2) has an optical thickness of less than 200 nm, preferably from 20 nm to 200 nm, particularly preferably from 50 nm to 200 nm, most preferably from 70 nm to 200 nm.
5. Composite disk (V) according to any one of claims 1 to 4, wherein the second optically high refractive index layer or layer sequence (3.3) has an optical thickness of less than 150 nm, preferably from 20 nm to 150 nm, particularly preferably from 50 nm to 150 nm, most preferably from 80 nm to 150 nm.
6. Composite disc (V) according to any one of claims 1 to 5, wherein the first optically high refractive index layer or layer sequence (3.1) and the second optically high refractive index layer or layer sequence (3.3) each independently comprise one or more dielectric layers based on titanium oxide, silicon nitride, silicon-metal mixed nitride, tungsten oxide, zinc oxide, niobium oxide, aluminum nitride, bismuth oxide, tantalum oxide, hafnium oxide, chromium oxide, tin oxide, zirconium oxide, titanium-zirconium oxide, silicon-zirconium oxide, hafnium oxide or tin-zinc oxide, preferably titanium oxide, silicon nitride, zinc oxide, tin-zinc oxide or silicon-metal mixed nitride.
7. Composite disk (V) according to any one of claims 1 to 6, wherein the first optically high refractive index layer or sequence of layers (3.1) and the second optically high refractive index layer or sequence of layers (3.3) are each formed as sequences of layers of individual layers with a thickness of at most 80 nm, preferably at most 50 nm.
8. Composite disc (V) according to one of claims 1 to 7, wherein the second optically high refractive layer or layer sequence (3.3) is formed as a layer sequence of individual layers, which as the uppermost layer comprises a cover layer based on titanium oxide, zirconium oxide, titanium zirconium oxide, silicon zirconium oxide or hafnium oxide with a thickness of at most 1 nm to 10 nm.
9. Composite disc (V) according to any one of claims 1 to 8, wherein the optically low refractive index layer or layer sequence (3.2) comprises one or more dielectric layers based on silicon oxide, nanoporous silicon oxide, magnesium fluoride or calcium fluoride, preferably a single layer based on silicon oxide. SAINT-GOBAIN GLASS FRANCE 2025016- WO-PCT 10. Composite pane (V) according to any one of claims 1 to 9, which is a window pane or a facade element of a building or a component thereof or a window pane of a vehicle, and wherein the glass pane (1) is exposed to the external environment of the building or vehicle and the second surface (II) is turned away from the external environment.
11. Composite disc (V) according to claim 10, wherein the further disc (4) is provided with an IR-reflective coating.
12. Composite disc (V) according to claim 11, wherein the IR-reflecting coating is a solar control coating (8) and comprises at least one electrically conductive layer based on silver.
13. Composite disc (V) according to claim 11, wherein the IR-reflecting coating is an emissivity-reducing coating and comprises at least one electrically conductive layer based on a transparent conductive oxide.
14. Composite disc (V) according to claim 10, wherein at least one photovoltaic component (6) is embedded in the intermediate layer (5).
15. Use of a composite pane (V) according to any one of claims 1 to 14 as a window pane or facade element of a building or as a component thereof or as a window pane of a vehicle, in particular a roof pane.