DE202020105642U1 - compound pane - Google Patents

Abstract

Laminated pane (1), at least comprising a laminated stack sequence
- An outer pane (2) with an outside surface (I) and an inside surface (II),
- An inner pane (3) with an outside surface (III) and an inside surface (IV), and
- At least one thermoplastic intermediate layer (4) which connects the interior surface (II) of the outer pane (2) to the outside surface (III) of the inner pane (3), wherein
- a heatable element (5) is applied directly to the interior-side surface (II) of the outer pane (2) or to the outside surface (III) of the inner pane (3), and
- A coating (6) reflecting heat rays is applied directly to the interior surface (IV) of the inner pane (3) and/or a coating (6) reflecting heat rays is applied directly to the outside surface (I) of the outer pane (2).

Description

The invention relates to a laminated pane that can be heated electrically.

Panes with an electric heating layer are known as such and have already been described many times in the patent literature. Merely as an example in this context DE 102008018147 A1 , DE 102008029986 A1 and WO 00/7263 A1 referred. In motor vehicles, they are often used as windscreens, since the central field of vision is not allowed to have any visual restrictions, with the exception of heating wires, due to legal requirements. The heat generated by the heating layer can remove condensed moisture, ice and snow in a short time. Such panes are usually manufactured as composite panes in which two individual panes are connected to one another by a thermoplastic adhesive layer. The heating layer can be applied to one of the inner surfaces of the individual panes, although structures are also known in which it is located on a carrier which is arranged between the two individual panes. Alternatively, a laminated pane can also be heated using heating wires. A composite pane with heatable wires is in the DE 103 52 464 A1 disclosed.

State-of-the-art heatable composite panes are a major electrical consumer in a vehicle. When voltage is applied, the heating element heats up and the heat is transported into the thermoplastic intermediate layer of the laminated pane, the outer pane and the inner pane by thermal conduction. Since glass generally conducts heat better than the thermoplastic intermediate layer, the heat from the heating element arranged on the outside of the inner pane is mainly conducted to the inner pane and is hardly conducted to the outer pane via the thermoplastic intermediate layer. Standard glass has an emissivity of around 80% to 90%. Thus, in the case of heatable laminated panes according to the prior art, the outside of the outer pane generally does not get as hot as the inside of the inner pane. A lot of energy is therefore consumed to remove ice and snow on the outside of the outer pane.

The object of the present invention is to provide a laminated pane which can be heated electrically and in which the heating function is improved.

According to the proposal of the invention, this object is achieved by a composite pane according to claim 1 . Advantageous configurations of the invention result from the dependent claims.

The invention relates to a laminated pane, at least comprising a laminated stack sequence of an outer pane with an outside surface and an inside surface, an inner pane with an outside surface and an inside surface and at least one thermoplastic intermediate layer, which connects the inside surface of the outside pane to the outside surface of the inner pane connects.

According to the invention, a heatable element is applied directly to the interior surface of the outer pane or to the outside surface of the inner pane.

In addition, according to the invention, a coating reflecting heat rays is applied directly to the interior surface of the inner pane and/or a coating reflecting heat rays is applied directly to the outside surface of the outer pane.

The laminated pane is intended to separate an interior space in a window opening, in particular the interior space of a vehicle or a building, from the outside environment. The composite pane is a laminate and comprises a first and a second glass pane, which are referred to as the outer pane and inner pane within the meaning of the invention and are connected to one another via a thermoplastic intermediate layer. In the context of the invention, inner pane refers to the pane facing the interior in the installed position. The outer pane refers to the pane facing the outside environment in the installed position. The surface on the interior side (inside surface or inside or inner surface) is understood within the meaning of the invention as that surface of the panes which faces the interior in the installed position. Within the meaning of the invention, the outside surface (or outside or outside surface) is understood to mean that surface of the panes which faces the external environment in the installed position.

• Die außenseitige Oberfläche der Außenscheibe wird als Seite I bezeichnet. Die innenraumseitige Oberfläche der Außenscheibe wird als Seite II bezeichnet. Die außenseitige Oberfläche der Innenscheibe wird als Seite III bezeichnet. Die innenraumseitige Oberfläche der Innenscheibe wird als Seite IV bezeichnet.

The surfaces of the glass panes are typically designated as follows:

• The outside surface of the outer pane is referred to as side I. The surface of the outer pane on the interior side is referred to as side II. The outside surface of the inner pane is referred to as Side III. The interior surface of the inner pane is referred to as side IV.

The interior surface II of the outer pane and the outside surface III of the inner pane face each other and are connected to one another by means of the at least one thermoplastic intermediate layer.

According to the invention, a coating that reflects the heat rays is applied directly to the interior surface IV of the inner pane and/or directly to the outside surface I of the outer pane. Such coatings are, for example, from WO2013/131667A1 famous. The thermal ray reflective coating may also be referred to as a low emissivity coating, emissivity reducing coating, thermal ray reducing coating, low-E coating or low-E layer. It has the task of reflecting thermal radiation, i.e. in particular IR radiation, which has longer wavelengths than the IR portion of solar radiation.

The thermal radiation-reflecting coating preferably extends over the entire interior surface IV of the inner pane and/or over the entire outside surface I of the outer pane.

It is also possible for the coating that reflects heat rays to extend over only part of the interior surface IV of the inner pane and/or over only part of the outside surface I of the outer pane.

In one embodiment, a protective layer is applied to the thermal radiation-reflecting coating. This optional protective layer serves to protect against corrosion and/or damage.

In a particularly advantageous embodiment of the invention, the heatable element is applied directly to the outside surface III of the inner pane, and a coating that reflects heat rays is applied directly to the inside surface IV of the inner pane.

In a further advantageous embodiment of the invention, the heatable element is applied directly to the interior surface II of the outer pane and a thermal radiation-reflecting coating is applied directly to the interior surface IV of the inner pane.

In a further advantageous embodiment of the invention, the heatable element is applied directly to the interior surface II of the outer pane and a thermal radiation-reflecting coating is applied directly to the outside surface I of the outer pane.

In a further advantageous embodiment of the invention, the heatable element is applied directly to the outside surface III of the inner pane and a coating that reflects heat rays is applied directly to the outside surface I of the outer pane.

In a further advantageous embodiment of the invention, the heatable element is applied directly to the outside surface III of the inner pane, a coating that reflects heat rays is applied directly to the outside surface IV of the inner pane, and a coating that reflects heat rays is applied directly to the outside surface I of the outer pane .

In a further advantageous embodiment of the invention, the heatable element is applied directly to the interior surface II of the outer pane, a coating that reflects heat rays is applied directly to the outside surface IV of the inner pane, and a coating that reflects heat rays is applied directly to the outside surface I of the outer pane .

When a thermal radiation-reflecting coating is arranged on the interior-side surface IV of the inner pane, this prevents inward thermal radiation from the inner pane heated by the heatable element. This reduces the emission of thermal radiation into the interior and heats the laminated pane more efficiently.

When a thermal radiation-reflecting coating is arranged on the outside surface I of the outer pane, this prevents the thermal radiation of the outer pane heated by the heatable element to the outside. This reduces the emission of thermal radiation into the external environment and heats the laminated pane more efficiently.

If a thermal radiation-reflecting coating is arranged on the interior surface IV of the inner pane and a thermal radiation-reflecting coating on the outside surface I of the outer pane, both the thermal radiation from the inner pane heated by the heatable element and the thermal radiation from the outer pane heated by the heatable element can be directed inward be prevented on the outside, so that the laminated pane is heated particularly efficiently and the release of thermal radiation into the external environment or the interior is reduced.

As described above, in the laminated pane according to the invention, heat rays The reflective coating on the interior surface IV of the inner pane reduces the emission of thermal radiation into the interior and/or the thermal radiation-reflecting coating on the outside surface I of the outer pane reduces the emission of thermal radiation into the external environment, as a result of which the laminated pane is heated more efficiently than laminated panes according to the state of the art. The laminated panes according to the invention consume less electricity for the same heating effect than laminated panes according to the prior art. The same heating effect is achieved earlier or less power has to be provided in order to achieve the same heating effect within a certain time.

The thermal radiation-reflecting coating on the interior surface IV of the inner pane and/or the thermal radiation-reflecting coating on the outside surface I of the outer pane reduce both the emission of thermal radiation from the vehicle interior into the external environment at cold outside temperatures and the thermal radiation or cold radiation in the vehicle interior is reduced. This reduces the so-called cold-wall effect.

The heatable element can be designed as a heatable coating.

The heatable coating preferably comprises a layer system with at least one metal layer embedded between dielectric oxide or nitride layers, in particular at least one metallic silver layer.

Alternatively, the heatable element can be in the form of a heatable wire, with a tungsten wire being preferred.

The heatable element can also be designed, for example, in the form of printed silver wires.

The heatable element designed as a heatable coating preferably extends over the entire interior surface II of the outer pane minus a peripheral, frame-shaped, coating-free area with a width of 1 mm to 50 cm, preferably 2 mm to 20 cm, and particularly preferably 1 cm to 20 cm , or over the entire outside surface III of the inner pane minus a peripheral, frame-shaped, coating-free area with a width of 1 mm to 50 cm, preferably 2 mm to 20 cm and particularly preferably 1 cm to 20 cm. The uncoated edge area is hermetically sealed by gluing to the thermoplastic intermediate layer. This advantageously protects the heatable coating from damage and corrosion, which emanates in particular from the edge of the laminated pane.

Alternatively, the heatable coating can also extend over the entire interior surface II of the outer pane or over the entire outside surface III of the inner pane.

Optionally, local areas that are used as communication, sensor or camera windows that are intended to ensure the transmission of electromagnetic radiation through the laminated pane are not provided with the heatable coating and/or not with the coating that reflects heat rays.

The heatable coating and the coating that reflects heat rays are each a transparent, functional coating that is intended to provide the pane surface with changed properties. According to the invention, a coating is considered to be transparent if it has an average transmission in the visible spectral range of at least 70%, preferably at least 80%, and as a result does not significantly restrict the view through the vehicle window. The heatable coating and the coating that reflects heat rays are each in particular a thin-layer coating, ie designed as a thin layer or thin-layer stack.

A heatable coating is an electrically conductive coating through which current flows when electrically contacted. The electrical conductivity is provided in particular by the fact that one or more individual layers of the coating are formed as electrically conductive layers, for example based on a metal, in particular based on silver, alternatively based on gold, aluminum or copper, for example. In addition to the at least one electrically conductive layer, there are usually dielectric layers which, for example, are intended to increase light transmission as antireflection layers, improve the crystallinity of the electrically conductive layer as adaptation layers or improve the surface structure for the overlying layers as smoothing layers. Common materials for the dielectric layers include silicon nitride, titanium oxide, aluminum nitride, tin oxide, zinc oxide, tin-zinc composite oxide, and silicon oxide.

The thickness of an electrically conductive layer of the heatable coating is preferably from 5 nm to 50 nm, particularly preferably from 8 nm to 25 nm. In this range for the thickness of the electrically conductive layer, an advantageously high transmission in the visible spectral range and a particularly advantageous electrical conductivity are achieved.

At least one dielectric layer is typically arranged in each case between two adjacent electrically conductive layers of the heatable coating. A further dielectric layer is preferably arranged below the first and/or above the last electrically conductive layer. A dielectric layer contains at least a single layer of a dielectric material, for example a nitride such as silicon nitride or an oxide such as aluminum oxide. However, the dielectric layer can also comprise a plurality of individual layers, for example individual layers of a dielectric material, smoothing layers, matching layers, blocking layers and/or antireflection layers. The thickness of a dielectric layer is, for example, from 10 nm to 200 nm.

This layer structure is generally obtained by a sequence of deposition operations carried out by a vacuum process such as magnetic field-assisted sputtering.

Heatable coatings are known, for example, from WO2013/104438 A1 , WO2013/104439 A1 or WO 2016/020113 A1 .

The heatable coating can, for example, also one of the WO 2019/179683 A1 or the WO 2020/094422 A1 described conductive coatings.

The thermal radiation-reflecting coating preferably comprises a functional layer containing a transparent conductive oxide (TCO), preferably indium tin oxide (ITO, indium tin oxide), tin oxide doped with antimony or fluorine and/or zinc oxide doped with gallium and/or aluminum (ZnO : Ga, or ZnO: AI), with indium tin oxide being preferred. However, the functional layer can also contain other electrically conductive oxides, for example fluorine-doped tin oxide (SnO ₂ :F), antimony-doped tin oxide (SnO ₂ :Sb), indium-zinc mixed oxide (IZO), gallium-doped or aluminum -doped zinc oxide, niobium-doped titanium oxide, cadmium stannate and/or zinc stannate. This achieves particularly good results with regard to the emissivity and the flexibility of the coating according to the invention. The refractive index of the material of the functional layer is preferably 1.7 to 2.5.

The indium tin oxide is preferably deposited by means of magnetic field-assisted sputtering with an indium tin oxide target. The target preferably contains from 75% by weight to 95% by weight of indium oxide and from 5% by weight to 25% by weight of tin oxide as well as admixtures caused by production. The tin-doped indium oxide is preferably deposited under a protective gas atmosphere, for example argon. A small proportion of oxygen can also be added to the protective gas, for example to improve the homogeneity of the functional layer.

Alternatively, the target may preferably contain at least from 75% to 95% by weight indium and from 5% to 25% by weight tin. The indium tin oxide is then preferably deposited with the addition of oxygen as reaction gas during cathode sputtering.

The coating which reflects heat rays also typically comprises dielectric layers, in particular formed from dielectric oxides or nitrides, such as ZnO, SnZnO, AlN, TiO ₂ , SiO ₂ or Si ₃ N ₄ . The layer of reflective conductive oxide is anti-reflective using additional dielectric layers above and below to ensure sufficiently low reflection from the inside.

The emissivity of the pane according to the invention can be influenced by the thickness of the functional layer of the thermal radiation-reflecting coating. The thickness of the functional layer is preferably 40 nm to 200 nm, particularly preferably 60 nm to 150 nm and very particularly preferably 65 nm to 85 nm, for example about 75 nm. Particularly advantageous values for the emissivity and a particularly advantageous ability of the heat ray reflective coating to withstand mechanical transformation such as bending or toughening without damage.

The interior-side emissivity of the laminated pane according to the invention is preferably less than or equal to 50%, particularly preferably from 10% to 50%, very particularly preferably from 10% to 35%. Interior-side emissivity is the measure that indicates how much heat radiation the pane emits in the installed position compared to an ideal heat radiator (a black body) in an interior space, for example a building or a vehicle. Within the meaning of the invention, emissivity is understood to mean the normal degree of emission at 283 K according to the EN 12898 standard.

In one embodiment of the invention, the heatable element, which as described above can be in the form of a heatable coating or heatable wires, is connected to a voltage source in order to conduct an electric current through the heatable element, which heats up as a result. Suitable voltages are the on-board voltages customary in the vehicle sector, for example 12 V to 14 V or typical on-board voltages of up to 500 V for electric vehicles. For connection to the voltage source, the heatable element is preferably provided with busbars, which are Voltage source can be connected. The busbars can, for example, be in the form of printed and burned-in conductors, typically in the form of a burned screen-printing paste with glass frits and silver particles. Alternatively, however, strips of an electrically conductive foil can also be used as busbars, which are placed or glued onto the heatable coating or the ends of the heatable wires, for example copper foil or aluminum foil. Typically, the two busbars are positioned near two opposite edges of the laminated pane, such as the top and bottom edges.

The thermoplastic intermediate layer is formed by one or more thermoplastic polymer films. The thermoplastic films preferably contain polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), polyurethane (PU) and/or mixtures thereof and/or copolymers thereof, particularly preferably polyvinyl butyral. The films are preferably based on the materials mentioned, but can contain other components, for example plasticizers, colorants, IR or UV absorbers, preferably in a proportion of less than 50%.

The individual polymer films, in particular the PVB films, preferably have a thickness of about 0.025 mm (25 μm) to 1 mm, in particular from 25 μm to 125 μm and from 0.3 mm to 1 mm, for example 50 μm, 100 μm, 0.38mm or 0.76mm. Other properties of the laminated glass pane can be influenced via the thickness of the foils. For example, thicker PVB films bring about improved soundproofing, especially if they contain an acoustically effective core, increased burglary resistance of the laminated glass pane and also increased protection against ultraviolet radiation (UV protection).

In an advantageous embodiment, the thermoplastic intermediate layer is formed from one or more polyvinyl butyral films.

Furthermore, the thermoplastic intermediate layer can be a functional intermediate layer, in particular an intermediate layer with acoustically damping properties, an intermediate layer that is tinted at least in sections and/or an intermediate layer that is colored at least in sections.

The outer pane and/or the inner pane can be made of glass and/or polymers, preferably soda-lime glass, alkali aluminosilicate glass, polycarbonate and/or polymethyl methacrylate. In a particularly preferred embodiment, the outer pane and the inner pane are made of glass.

Suitable glass sheets include glass sheets known under the trade names Planiclear and Planilux (each clear glass), VG10, VG20, VG40 or TSANx, TSA3+, TSA4+ from Saint-Gobain, the glasses of the VG series being grey-tinted glasses and bei those of the TSA series are green colored lenses.

The outer pane and/or the inner pane preferably have a thickness of 0.5 mm to 4 mm, particularly preferably a thickness of 1.6 mm to 2.1 mm. The outer pane and/or the inner pane can have a constant thickness or can also be slightly wedge-shaped.

The outer pane, the inner pane and the at least one thermoplastic intermediate layer can be clear and colorless, but can also be tinted or colored. In a preferred embodiment, the total transmission through the laminated glass is greater than 70%. The term total transmission refers to the procedure specified by ECE-R 43, Appendix 3, Section 9.1 for testing the light transmittance of motor vehicle windows. The outer pane and the inner pane can be unprestressed, partially prestressed or prestressed independently of one another. If at least one of the panes is to have a prestress, this can be a thermal or chemical prestress

The laminated pane is preferably curved in one or more spatial directions, as is customary for motor vehicle panes, with typical radii of curvature being in the range from about 10 cm to about 40 m. However, the composite pane can also be flat, for example if it is intended as a pane for buses, trains or tractors.

The outer pane, the inner pane and the at least one thermoplastic intermediate layer can have suitable coatings known per se, for example anti-reflective coatings, Non-stick coatings, anti-scratch coatings or photocatalytic coatings.

The heatable element can be connected to a voltage source as described above. According to the invention, therefore, a laminated pane as described above, in which the heatable element is connected to a voltage source.

A laminated pane according to the invention can additionally include a cover print, in particular made of a dark, preferably black, enamel. The masking print is in particular a peripheral, i.e. frame-like, masking print. The peripheral masking print primarily serves as UV protection for the assembly adhesive of the laminated pane. The cover print can be opaque and full-surface. The cover print can also be semi-transparent, at least in sections, for example as a dot grid, stripe grid or checkered grid. Alternatively, the covering print can also have a gradient, for example from an opaque covering to a semi-transparent covering. The masking print is usually applied to the interior surface of the outer pane or to the interior surface of the inner pane, with the masking print preferably being applied to a pane surface on which neither a heatable coating nor a coating that reflects heat rays is arranged in the laminated pane according to the invention.

1. a) Bereitstellung einer Außenscheibe mit einer außenseitigen Oberfläche I und einer innenraumseitigen Oberfläche II, einer Innenscheibe mit einer außenseitigen Oberfläche III und einer innenraumseitigen Oberfläche IV, und mindestens einer thermoplastischen Zwischenschicht, wobei ein beheizbares Element direkt auf die innenraumseitige Oberfläche II der Außenscheibe oder auf die außenseitige Oberfläche III der Innenscheibe aufgebracht ist und eine Wärmestrahlen reflektierende Beschichtung direkt auf die innenraumseitige Oberfläche IV der Innenscheibe und/oder eine Wärmestrahlen reflektierende Beschichtung direkt auf die außenseitige Oberfläche I der Außenscheibe aufgebracht ist;
2. b) Bilden einer Stapelfolge aus der Außenscheibe, der mindestens einen thermoplastischen Zwischenschicht und der Innenscheibe, derart, dass die innenraumseitige Oberfläche II der Außenscheibe und die außenseitige Oberfläche III der Innenscheibe einander zugewandt sind und die mindestens eine thermoplastische Zwischenschicht zwischen der Außenscheibe und der Innenscheibe angeordnet ist;
3. c) Verbinden der Außenscheibe und der Innenscheibe über die mindestens eine thermoplastische Zwischenschicht zu einer Verbundscheibe in einem Laminationsverfahren.

The laminated pane according to the invention can be produced using a method comprising the following steps:

1. a) Provision of an outer pane with an outside surface I and an inside surface II, an inner pane with an outside surface III and an inside surface IV, and at least one thermoplastic intermediate layer, with a heatable element directly on the inside surface II of the outside pane or on the outside surface III of the inner pane is applied and a coating reflecting heat rays is applied directly to the interior surface IV of the inner pane and/or a coating reflecting heat rays is applied directly to the outside surface I of the outer pane;
2. b) forming a stack sequence from the outer pane, the at least one thermoplastic intermediate layer and the inner pane, such that the interior surface II of the outer pane and the outer surface III of the inner pane face each other and the at least one thermoplastic intermediate layer is arranged between the outer pane and the inner pane is;
3. c) Connecting the outer pane and the inner pane via the at least one thermoplastic intermediate layer to form a composite pane in a lamination process.

The lamination is preferably carried out under the action of heat, vacuum and/or pressure. Methods known per se can be used for lamination, for example autoclave methods, vacuum bag methods, vacuum ring methods, calendering methods, vacuum laminators or combinations thereof.

The thermal radiation-reflecting coating is preferably applied by physical vapor deposition (PVD) to the interior surface IV of the inner pane and/or to the outside surface I of the outer pane, particularly preferably by cathode sputtering ("sputtering"), very particularly preferably by magnetic field-assisted cathode sputtering.

If the heatable element is designed as a heatable coating, this is preferably applied by physical vapor deposition (PVD) to the interior surface II of the outer pane or to the outside surface III of the inner pane, particularly preferably by cathode atomization ("sputtering"), very particularly preferably by magnetic field-assisted cathode sputtering.

It goes without saying that busbars required for connecting the heatable element to a voltage source are applied before the lamination step.

If the composite pane is to be curved, the outer pane and the inner pane are preferably subjected to a bending process before lamination and preferably after any coating processes. The outer pane and the inner pane are preferably bent congruently together (i.e. at the same time and using the same tool), because the shape of the panes is then optimally matched to one another for the lamination that takes place later. Typical temperatures for glass bending processes are 500°C to 700°C, for example.

The composite pane according to the invention can be used in a vehicle on water, on land or in the air, preferably as a windscreen of a vehicle, particularly preferably as a windscreen of a motor vehicle, in particular a passenger car. Alternatively, the composite pane according to the invention in a Building glazing or used in other architectural glazing.

The various configurations of the invention can be implemented individually or in any combination. In particular, the features mentioned above and explained below can be used not only in the specified combinations, but also in other combinations or on their own, without departing from the scope of the present invention.

• 1 eine Draufsicht auf eine Ausgestaltung einer erfindungsgemäßen Verbundscheibe,
• 2 den Querschnitt durch die in der 1 gezeigte Ausgestaltung einer erfindungsgemäßen Verbundscheibe,
• 3 den Querschnitt durch eine weitere Ausgestaltung einer erfindungsgemäßen Verbundscheibe,
• 4 den Querschnitt durch eine weitere Ausgestaltung einer erfindungsgemäßen Verbundscheibe,
• 5 den Querschnitt durch eine weitere Ausgestaltung einer erfindungsgemäßen Verbundscheibe,
• 6 den Querschnitt durch eine weitere Ausgestaltung einer erfindungsgemäßen Verbundscheibe,
• 7 den Querschnitt durch eine weitere Ausgestaltung einer erfindungsgemäßen Verbundscheibe, und
• 8 den Querschnitt durch eine weitere Ausgestaltung einer erfindungsgemäßen Verbundscheibe.

The invention will now be explained in more detail using exemplary embodiments, reference being made to the accompanying figures. The figures do not limit the invention in any way. They show in a simplified representation that is not to scale:

• 1 a plan view of an embodiment of a composite pane according to the invention,
• 2 the cross section through the in the 1 shown embodiment of a composite pane according to the invention,
• 3 the cross section through a further embodiment of a composite pane according to the invention,
• 4 the cross section through a further embodiment of a composite pane according to the invention,
• 5 the cross section through a further embodiment of a composite pane according to the invention,
• 6 the cross section through a further embodiment of a composite pane according to the invention,
• 7 the cross section through a further embodiment of a composite pane according to the invention, and
• 8th the cross section through a further embodiment of a composite pane according to the invention.

1 shows a plan view of an embodiment of a laminated pane 1 and according to the invention 2 shows the cross section through the in the 1 composite pane shown along section line X-X'. As in the 1 and 2 As can be seen, the laminated pane 1 has an upper edge O and a lower edge U and two side edges S. The laminated pane 1 comprises an outer pane 2 and an inner pane 3, which are laminated to one another via a thermoplastic intermediate layer 4 and are thereby permanently connected. The laminated pane 1 is provided, for example, as a windshield of a passenger car, with the outer pane 2 being intended to face the outside environment and the inner pane 3 being intended to face the vehicle interior. The outer pane 2 has an outside surface I and an inside surface II. The inner pane 3 has an outside surface III and an inside surface IV. The outside surfaces I and III face the outside environment in the installed position, the interior surfaces II and IV face the vehicle interior in the installed position. The interior surface II of the outer pane 2 and the outside surface III of the inner pane 3 face each other. The outer pane 2 contains, for example, soda-lime glass and has a thickness of 2.1 mm, for example. The inner pane 3 contains, for example, soda-lime glass and has a thickness of 1.6 mm, for example. The thermoplastic intermediate layer 4 contains or consists of polyvinyl butyral (PVB) and has a thickness of 0.76 mm, for example. It goes without saying that composite panes 1 according to the invention can also have other dimensions adapted to the respective individual case and in particular other layer thicknesses for the outer pane 2 , inner pane 3 and thermoplastic intermediate layer 4 .

A heatable element 5 in the form of a heatable coating is arranged on the outside surface III of the inner pane 3 . The heatable coating is, for example, as in FIG WO 2020/094422 A1 and comprises at least four electrically conductive silver layers, each of which is arranged between two dielectric layers or layer sequences, the sum of the thicknesses of all electrically conductive silver layers being at most 30 nm and at least one of the electrically conductive silver layers being at most 5 nm thick.

A coating 6 reflecting heat rays is arranged on the interior surface IV of the inner pane 3 . The coating 6 that reflects heat rays includes, for example, a functional ITO layer with a thickness of 60 nm to 150 nm and also further dielectric layers above and below the functional layer, in particular made of Al-doped SiO ₂ and Si ₃ N ₄ .

The thermal radiation reflecting coating 6 reduces the radiation of the thermal radiation emitted by the heatable element 5 designed as a heatable coating through the laminated pane into the vehicle interior. On the other hand, the thermal radiation-reflecting coating 6 also reduces the emission of thermal radiation from the vehicle interior at low outside temperatures.

The heatable element 5 can be connected to a voltage source via busbars (in the 1 and 2 not drawn).

In the 3 the cross section of a further embodiment of a composite pane 1 according to the invention is shown. The one in the 3 Composite pane 1 shown in cross section differs from that in FIG 2 Composite pane 1 shown in cross section only in that the heatable element 5 designed as a heatable coating is not applied to the outside surface III of the inner pane 3, but to the inside surface II of the outer pane 2.

the 4 shows a cross section of a further embodiment of a laminated pane 1 according to the invention 4 The laminated pane 1 shown in cross section comprises an outer pane 2 and an inner pane 3, which are laminated to one another via a thermoplastic intermediate layer 4 and are thereby permanently connected. The laminated pane 1 is provided, for example, as a windshield of a passenger car, with the outer pane 2 being intended to face the outside environment and the inner pane 3 being intended to face the vehicle interior. The outer pane 2 has an outside surface I and an inside surface II. The inner pane 3 has an outside surface III and an inside surface IV. The outside surfaces I and III face the outside environment in the installed position, the interior surfaces II and IV face the vehicle interior in the installed position. The interior surface II of the outer pane 2 and the outside surface III of the inner pane 3 face each other. The outer pane 2 contains, for example, soda-lime glass and has a thickness of 2.1 mm, for example. The inner pane 3 contains, for example, soda-lime glass and has a thickness of 1.6 mm, for example. The thermoplastic intermediate layer 4 contains or consists of polyvinyl butyral (PVB) and has a thickness of 0.76 mm, for example. It goes without saying that composite panes 1 according to the invention can also have other dimensions adapted to the respective individual case and in particular other layer thicknesses for the outer pane 2 , inner pane 3 and thermoplastic intermediate layer 4 .

A heatable element 5 in the form of a heatable coating is arranged on the inside surface II of the outer pane 2 .

The heatable coating is, for example, as in FIG WO 2020/094422 A1 and comprises at least four electrically conductive silver layers, each of which is arranged between two dielectric layers or layer sequences, the sum of the thicknesses of all electrically conductive silver layers being at most 30 nm and at least one of the electrically conductive silver layers being at most 5 nm thick.

On the outside surface I of the outer pane 2 there is a coating 6 which reflects heat rays. The coating 6 that reflects heat rays includes, for example, a functional ITO layer with a thickness of 60 nm to 150 nm and also further dielectric layers above and below the functional layer, in particular made of Al-doped SiO ₂ and Si ₃ N ₄ .

The thermal radiation-reflecting coating 6 reduces, on the one hand, the radiation of the thermal radiation emitted by the heatable element 5, which is designed as a heatable coating, through the laminated pane to the outside. On the other hand, the thermal radiation-reflecting coating 6 also reduces the emission of thermal radiation from the vehicle interior at low outside temperatures.

5 shows the cross section of a further embodiment of a laminated pane 1 according to the invention 5 Composite pane 1 shown in cross section differs from that in FIG 4 shown in cross section only in that the heatable element 5 designed as a heatable coating is not arranged on the interior surface II of the outer pane 2 but on the outside surface III of the inner pane 3 .

6 shows the cross section of a further embodiment of a laminated pane 1 according to the invention 6 Composite pane 1 shown in cross section differs from that in FIG 2 shown in cross-section only to the extent that a thermal radiation-reflecting coating 6 is additionally applied to the outside surface I of the outer pane 2 .

7 shows the cross section of a further embodiment of a laminated pane 1 according to the invention 7 Composite pane 1 shown in cross section differs from that in FIG 3 shown in cross-section only to the extent that a thermal radiation-reflecting coating 6 is additionally applied to the outside surface I of the outer pane 2 .

In the 8th is the cross section of another embodiment of a Ver according to the invention flange disc 1 shown. The one in the 8th The embodiment of a laminated pane 1 according to the invention shown in cross section differs from that in FIG 2 illustrated only to the effect that the heatable element 5 is designed as an arrangement of heatable wires. The heatable wires are, for example, tungsten wires with a diameter between 10 μm and 33 μm. This can involve, for example, a plurality of wires arranged parallel to one another or a single wire which extends in a serpentine manner over the outside surface III of the inner pane 3 .

Reference List

1

composite pane

2

outer pane

3

inner pane

4

thermoplastic intermediate layer

5

heatable element

6

Coating reflecting heat rays

X-X'

cutting line

O

top edge

u

bottom edge

S

side edge

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• DE 102008018147 A1 [0002]
• DE 102008029986 A1 [0002]
• WO 00/7263 A1 [0002]
• DE 10352464 A1 [0002]
• WO 2013/131667 A1 [0012]
• WO 2013/104438 A1 [0039]
• WO 2013/104439 A1 [0039]
• WO 2016/020113 A1 [0039]
• WO 2019/179683 A1 [0040]
• WO 2020/094422 A1 [0040, 0070, 0077]

Claims (15)

Laminated pane (1), at least comprising a laminated stack sequence - An outer pane (2) with an outside surface (I) and an inside surface (II), - An inner pane (3) with an outside surface (III) and an inside surface (IV), and - At least one thermoplastic intermediate layer (4) which connects the interior surface (II) of the outer pane (2) to the outside surface (III) of the inner pane (3), wherein - a heatable element (5) is applied directly to the interior-side surface (II) of the outer pane (2) or to the outside surface (III) of the inner pane (3), and - A coating (6) reflecting heat rays is applied directly to the interior surface (IV) of the inner pane (3) and/or a coating (6) reflecting heat rays is applied directly to the outside surface (I) of the outer pane (2). Composite pane (1) after claim 1 , wherein the heatable element (5) is applied directly to the outside surface (III) of the inner pane (3) and a thermal radiation-reflecting coating (6) is applied directly to the inside surface (IV) of the inner pane (3). Composite pane (1) after claim 1 , wherein the heatable element (5) is applied directly to the interior-side surface (II) of the outer pane (1) and a thermal radiation-reflecting coating (6) is applied directly to the interior-side surface (IV) of the inner pane (3). Composite pane (1) after claim 1 , wherein the heatable element (5) is applied directly to the interior-side surface (II) of the outer pane (1) and a thermal radiation-reflecting coating (6) is applied directly to the outside surface (I) of the outer pane (2). Composite pane (1) after claim 1 , wherein the heatable element (5) is applied directly to the outside surface (III) of the inner pane (3) and a thermal radiation-reflecting coating (6) is applied directly to the outside surface (I) of the outer pane (2). Composite pane (1) after claim 1 , wherein the heatable element (5) is applied directly to the outside surface (III) of the inner pane (3), a coating (6) reflecting heat rays is applied directly to the outside surface (IV) of the inner pane (3) and a heat-ray reflecting coating Coating (6) is applied directly to the outside surface (I) of the outer pane (2). Composite pane (1) after claim 1 , wherein the heatable element (5) is applied directly to the interior surface (II) of the outer pane (1), a thermal radiation-reflecting coating (6) is applied directly to the outside surface (IV) of the inner pane (3) and a thermal radiation-reflecting Coating (6) is applied directly to the outside surface (I) of the outer pane (2). Composite pane (1) according to one of Claims 1 until 7 , wherein the heatable element (5) is designed as a heatable coating. Composite pane (1) after claim 8 , wherein the heatable coating comprises a layer system with at least one metal layer embedded between dielectric oxide or nitride layers, in particular at least one metallic silver layer. Composite pane (1) according to one of Claims 1 until 7 , wherein the heatable element (5) is designed as at least one heatable wire, in particular as a tungsten wire. Composite pane (1) according to one of Claims 1 until 10 , wherein the coating (6) reflecting heat rays contains a transparent conductive oxide, preferably indium tin oxide, tin oxide doped with antimony or fluorine and/or zinc oxide doped with aluminum (ZnO:Al) and/or zinc oxide doped with gallium (ZnO:Ga) and in particular preferably consists of indium tin oxide. Composite pane (1) according to one of Claims 1 until 11 , wherein the thermoplastic intermediate layer (4) is formed from at least one polymer film which preferably contains polyvinyl butyral, ethylene vinyl acetate, polyurethane and/or mixtures thereof and/or copolymers thereof and preferably consists of polyvinyl butyral. Composite pane (1) according to one of Claims 1 until 12 , wherein the outer pane (2) and/or the inner pane (3) is formed from glass and/or polymers, preferably soda-lime glass, alkali aluminosilicate glass, polycarbonate and/or polymethyl methacrylate. Composite pane (1) according to one of Claims 1 until 13 , the outer pane (2) and/or the inner pane (3) having a thickness of 0.5 mm to 4 mm, particularly preferably from 1.6 mm to 2.1 mm. Composite pane (1) according to one of Claims 1 until 14 , wherein the heatable element (5) is connected to a voltage source.

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