WO2022112582A1

WO2022112582A1 - Method for producing a curved pane with a functional layer

Info

Publication number: WO2022112582A1
Application number: PCT/EP2021/083459
Authority: WO
Inventors: Jefferson DO ROSARIO; Anna NEFT; Stefanie PENGEL
Original assignee: Saint-Gobain Glass France
Priority date: 2020-11-30
Filing date: 2021-11-30
Publication date: 2022-06-02
Also published as: DE202021004211U1; CN114845866A

Abstract

The present invention relates to a method for producing a curved pane (100) with a functional layer (105), comprising the following steps: - providing (S101) the pane (100) and applying (S101) a sacrificial layer (101) to a first region (103-1) of the pane (100); - applying (S102) the functional layer (105) to the sacrificial layer (101) and a second region (103-2) of the pane (100); - removing (S103) the sacrificial layer (101) from the first region (103-1) of the pane (100), the functional layer (105) also being removed from the first region (103-1) of the pane (100), in which the sacrificial layer (101) contains or consists of at least one polymeric organic compound, wherein the polymeric organic compound is a light-curable or heat-curable organic compound, and wherein the sacrificial layer (101) is destroyed by heating during a heat treatment to bend the pane (100).

Description

Process for manufacturing a curved pane with a functional layer

The present invention is in the technical field of disk production and relates to a method for producing a curved disk with a functional layer and a curved disk with a functional layer manufactured by the method according to the invention. Furthermore, the invention extends to a method for producing glazing, which includes the method according to the invention for producing a curved pane with a functional layer.

Glazing in buildings and vehicles is increasingly being provided with large, electrically conductive layers that are transparent to visible light and that have to fulfill certain functions. These layers are commonly referred to as functional layers. For example, high demands are placed on glazing with regard to its heat-insulating properties for reasons of energy saving and comfort. So it is desirable to avoid a high heat input through solar radiation, which leads to excessive heating of the interior and in turn results in high energy costs for the necessary air conditioning. This can be remedied by electrochromic layers, in which the light transmission and thus the heat input due to solar radiation can be controlled by applying an electrical voltage. Electrochromic layers are well known in the technical field and have already found their way into the patent literature in many cases, reference being made to EP 0867752 A1, US 2007/0097481 A1 and US 2008/0169185 A1 merely by way of example.

The use of layers that reflect thermal radiation (low-E layers) is also known. A low-E layer reflects a significant part of the incoming solar radiation, especially in the infrared range, which leads to reduced heating of the interior in summer. The Low-E layer also reduces the emission of long-wave thermal radiation from a heated pane into the interior when the Low-E layer is applied to the surface of a pane facing the interior. In winter, when outside temperatures are low, the heat from the interior is prevented from radiating to the outside environment. Low-E layers, for example based on niobium, tantalum, nickel, chromium, zirconium or alloys thereof, are well known to the person skilled in the art, for example from US7592068 B2, US7923131 B2 and WO2004076174 A1. Another application of functional layers aims to keep the field of vision of a vehicle window free of ice and fog. Electrical heating layers are known which cause targeted heating of the vehicle window by applying an electrical voltage (see, for example, WO 2010/043598 A1).

In a further application, the functional layer is used as a planar antenna in motor vehicles. For this purpose, the functional layer is galvanically or capacitively coupled to a coupling electrode and the antenna signal is made available in the edge area of the pane. The antenna signal decoupled from the planar antenna is fed to an antenna amplifier, which is connected to the metal body of motor vehicles, whereby a reference potential effective for high-frequency technology is specified for the antenna signal. Such planar antennas are known, for example, from DE 10106125 A1, DE 10319606 A1, EP 0720249 A2, US 2003/0112190 A1 and DE 19843338 C2.

The production of a functional layer on a pane is usually associated with a great deal of effort and usually with a long process duration. A further complication is that in many cases it is necessary to apply the functional layer to only one area of the pane or to selectively remove the functional layer from a specific area of the pane.

GB 829709 A, US 2003/232197 A1, EP 1348674 A1, EP 1348673 A1 and WO 2020/216514 A1 each show a method in which a functional layer is applied to a locally applied masking layer, the functional layer also being removed when the masking layer is removed becomes.

In contrast, the object of the present invention is to provide an improved method for producing a curved pane with a functional layer, the main concern being to simplify the application of the functional layer in only one area of the pane. The curved pane with a functional layer should be simple and inexpensive to manufacture in industrial series production. In addition, the method should be simple and inexpensive to use in common manufacturing processes for curved panes.

According to the proposal of the invention, these and other objects are achieved by a method for producing a curved pane with a functional layer according to the independent patent claim resolved. Advantageous configurations of the invention result from the dependent claims.

According to the invention, a method for producing a curved pane of glass with a functional layer is shown. The method includes providing a disk and applying a sacrificial layer to at least a first portion of the disk. This is followed by the application of a functional layer to the sacrificial layer (i.e. to the first area of the wafer) and to at least a second area of the wafer where the sacrificial layer is not located. The sacrificial layer is then removed from the at least one first area of the pane, with the functional layer also being removed from the at least one first area of the pane. The functional layer remains on the at least one second area of the pane.

According to the present invention, by using a sacrificial layer applied only in sections, which is removed again from the pane, the functional layer can also be removed in a simple manner, with the functional layer remaining in one or more areas of the pane. As a result, different areas of the pane can be coated with the functional layer in a targeted manner, whereas one or more areas of the pane are free of the functional layer. This considerably simplifies the manufacturing process of the coated pane, which is a great advantage of the invention.

For the purposes of the present invention, the term “area” of the pane designates a part or continuous section of a pane surface on which the sacrificial layer and/or functional layer are located. The sacrificial layer and then the functional layer are applied to the first area of the pane. The functional layer, but not the sacrificial layer, is applied to the second area of the pane. The second area of the disc is different from the first area of the disc.

The sacrificial layer is applied to the pane in the first area of the pane. The sacrificial layer can be applied directly, i.e. immediately, to the pane, it being equally possible for at least one further layer of a different material than the sacrificial layer to be arranged between the sacrificial layer and the pane.

The functional layer is placed on the sacrificial layer (ie on the at least one first area of the pane) and on at least one area of the pane in which there is no sacrificial layer (ie to the at least one second region of the disc) applied. The functional layer can be applied directly, ie immediately, to the sacrificial layer, it being equally possible for at least one further layer made of a material different from the functional layer to be arranged between the functional layer and the sacrificial layer. Where the functional layer is not arranged on the sacrificial layer, it can be applied directly, ie immediately, to the pane, it being equally possible for at least one further layer made of a different material than the functional layer to be arranged between the functional layer and the pane .

The functional layer and the sacrificial layer can each consist of an individual layer or ply made of the same material, it being equally possible for them to consist of a plurality of individual layers or plies made of at least two different materials. The functional layer and sacrificial layer can thus each consist of an individual layer or layer of the same material. Alternatively, the functional layer and sacrificial layer can each consist of a plurality of individual layers or plies made of at least two different materials. As explained at the outset, it is common practice to form a functional layer in the form of a layer system made up of individual layers that are different from one another.

In principle, the sacrificial layer can be applied to the pane using any suitable method. According to preferred configurations of the method according to the invention, the sacrificial layer is applied to the pane by brushing, rolling, spraying or by means of screen printing. These are common methods in the industrial series production of panes and enable the sacrificial layer to be applied to the pane quickly and evenly.

In principle, the sacrificial layer can be removed from the pane again using any suitable method. According to a preferred embodiment of the method according to the invention, the sacrificial layer is removed from the pane by means of a liquid, as a result of which the sacrificial layer can be removed in a particularly simple manner. The liquid is particularly advantageously a solvent for the material of the sacrificial layer, so that the sacrificial layer is detached from the pane quickly and over a large area.

According to the invention, the sacrificial layer is destroyed by heating, which has the advantage that the sacrificial layer can be removed quickly and over a large area together with the functional layer arranged above it. The sacrificial layer is "sacrificed" in the manufacturing process and is used to remove the functional layer from the pane in sections. When the sacrificial layer is removed, the functional layer is also removed, ie the functional layer is not removed without also removing the sacrificial layer. For this purpose, the sacrificial layer consists of a suitable material that can be removed again from the pane in a relatively simple manner, with the sacrificial layer being decomposed by heating.

According to the invention, the sacrificial layer contains or consists of an organic material. For the purposes of the present invention, the term "material" includes a single chemical substance or several different chemical substances. According to the invention, the sacrificial layer contains or consists of a polymeric material, namely a light- or heat-curing polymeric material. The sacrificial layer preferably consists of a light- or heat-curing polymer layer. In the case of a light-curing polymer material, the sacrificial layer is irradiated with light after it has been applied to the pane in order to cure the sacrificial layer. In the case of a thermosetting polymeric material, the sacrificial layer is treated with heat after application to the disk in order to harden the sacrificial layer. Such sacrificial layers made of a light- or heat-curing polymer material can be destroyed and removed particularly well by heating. According to the invention, the sacrificial layer is destroyed during heat treatment of the pane, which serves to bend the pane.

The bending of (glass) panes is widely used in the industrial series production of glass panes and is well known to those skilled in the art. It has also been described many times in the patent literature, so that it does not need to be discussed in more detail here. Reference is made to WO 2012/080071 merely as an example. For the bending process, panes are heated in a furnace to at least the softening temperature of the glass, which is typically in the range from 500°C to 700°C, in particular in the range from 580°C to 650°C.

During the bending process, the pane with the sacrificial layer and the functional layer applied to it is bent in one or more spatial directions in the heated state. The sacrificial layer is advantageously destroyed by heating the sheet to bend and can be easily removed. It goes without saying that further thermal treatment steps of the pane can take place before or after the bending process. The sacrificial layer can thus be destroyed by the heat treatment of the pane for bending the pane and easily removed from the pane, the functional layer arranged on the sacrificial layer also being removed. A separate heating of the pane to destroy the sacrificial layer can thus advantageously be dispensed with, as a result of which time and costs can be saved in the industrial series production of panes. In addition, the process according to the invention can be integrated in a particularly simple manner into common manufacturing processes for panes.

According to a preferred embodiment of the method according to the invention, the sacrificial layer contains or consists of at least one (meth)acrylate compound. The term "(meth)acrylate" refers to an acrylate or a methacrylate. The term "(meth)acrylate compound" preferably means esters of acrylic acid or methacrylic acid, the compound having at least one acryloyl group (CH2=CH - CO - ) or one methacryloyl group (CH2=CH(CH3) - CO - ) contains. Such an ester can be a monomer, oligomer, prepolymer or polymer. Preferably, (meth)acrylate compounds produce a polymer network with a fixed structure when polymerized.

(Meth)acrylate compounds are preferably selected from monofunctional or polyfunctional (meth)acrylates, such as mono-, di-, tri- and poly-functional (meth)acrylates. Examples are: monofunctional (meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, n- or tert-butyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl ( meth)-acrylate, 2-ethylhexyl-(meth)-acrylate, benzyl-(meth)-acrylate, 2-ethoxyethyl-(meth)-acrylate, phenoxyethyl-(meth)-acrylate, hydroxyethyl-acrylate, hydroxypropyl-(meth) -acrylate, vinyl (meth)acrylate, caprolactone acrylate, isobornyl methacrylate, lauryl methacrylate, polypropylene glycol monomethacrylate; difunctional (meth)acrylates such as: 1,4-butanediol di(meth)acrylate, ethylene dimethacrylate, 1,6-hexanediol di(meth)acrylate, bisphenol A di(meth)acrylate, trimethylolpropane diacrylate, triethylene glycol diacrylate, ethylene glycol di(meth)acrylate,

polyethylene glycol di(meth)acrylate, tricyclodecane dimethanol diacrylate; trifunctional (meth)acrylates such as: trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, ethoxylated trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, tripropylene glycol triacrylate; or (meth)acrylates of a higher functionality such as: pentaerythritol tetra(meth)acrylate, ditrimethylpropane tetra(meth)acrylate, dipentaerythritol enta(meth)acrylate or hexa(meth)acrylate. (Meth)acrylate compounds particularly advantageously enable rapid and complete combustion of the sacrificial layer by heating to bend the disc and produce easily removable residual substances during decomposition.

In principle, the functional layer can be formed in any desired manner. It is preferably an electrically conductive coating that is transparent to visible light.

The functional layer is preferably applied to the pane over a large area. The functional layer is arranged on a surface of the pane and covers or covers the surface of the pane partially, but preferably over a large area. The term “large area” means that at least 50%, at least 60%, at least 70%, at least 75% or preferably at least 90% of the surface of the pane is covered by the functional layer. However, the functional layer can also extend over smaller portions of the surface of the pane. The functional layer is an individual layer or a layer structure made up of several individual layers with a total thickness of less than or equal to 2 μm, particularly preferably less than or equal to 1 μm. The functional layer advantageously has a thickness of 80 nm to 1000 nm, preferably 140 nm to 400 nm or preferably 700 nm to 900 nm.

In the context of the present invention, "transparent" means that the overall transmission of the pane corresponds to the legal provisions for windshields and front side windows and preferably has a permeability of more than 70% and in particular more than 75% for visible light. For rear side windows and rear windows, "transparent" can also mean 10% to 70% light transmission. Correspondingly, "opaque" means a light transmission of less than 15%, preferably less than 5%, in particular 0%.

For example, the transparent, electrically conductive functional layer contains at least one metal, for example silver, nickel, chromium, niobium, tin, titanium, copper, palladium, zinc, gold, cadmium, aluminum, silicon, tungsten or alloys thereof, and/or at least one metal oxide layer , preferably tin-doped indium oxide (ITO), aluminum-doped zinc oxide (AZO), fluorine-doped tin oxide (FTO, SnO 2 :F) or antimony-doped tin oxide (ATO, SnO 2 :Sb). Such functional layers are known, for example, from DE 20 2008 017 611 U1 and EP 0 847 965 B1. They consist, for example, of a metal layer such as a silver layer or a layer of a metal alloy containing silver. Typical silver layers preferably have thicknesses of 5 nm to 15 nm, more preferably 8 nm to 12 nm. The metal layer may be sandwiched between at least two layers of metal oxide type dielectric material be. The metal oxide preferably includes zinc oxide, tin oxide, indium oxide, titanium oxide, silicon oxide, aluminum oxide, or the like, and combinations of one or more thereof. The dielectric material may also include silicon nitride, silicon carbide, aluminum nitride, and combinations of one or more thereof.

Transparent, electrically conductive functional layers have, for example, a surface resistance of 0.1 ohms/square to 200 ohms/square, particularly preferably from 1 ohms/square to 50 ohms/square and very particularly preferably from 1 ohms/square to 10 ohms/square.

For example, the transparent, electrically conductive functional layer serves as an antenna layer (surface antenna).

For example, the functional layer is a functional layer with a sun protection effect. Such a layer with a sun protection effect has reflective properties in the infrared range and thus in the range of solar radiation, which advantageously reduces the heating of the interior of a building or motor vehicle as a result of solar radiation. Functional layers with a sun protection effect are well known to the person skilled in the art and typically contain at least one metal, in particular silver or a silver-containing alloy. The layer with a sun protection effect can comprise a sequence of several individual layers, in particular at least one metallic layer and dielectric layers, which contain at least one metal oxide, for example. The metal oxide preferably includes zinc oxide, tin oxide, indium oxide, titanium oxide, silicon oxide, aluminum oxide, or the like, and combinations of one or more thereof. The dielectric material contains silicon nitride, silicon carbide or aluminum nitride, for example. Layers with a sun protection effect are known, for example, from DE 102009006062 A1, WO 2007/101964 A1, EP 0 912 455 B1, DE 19927683 C1, EP 1 218 307 B1 and EP 1 917 222 B1.

The thickness of a functional layer with a sun protection effect can vary widely and be adapted to the requirements of the individual case, with a layer thickness of 10 nm to 5 μm and in particular from 30 nm to 1 μm being preferred. The surface resistance of a layer with a sun protection effect is preferably from 0.35 ohms/square to 200 ohms/square, preferably from 0.5 ohms/square to 200 ohms/square, very particularly preferably from 0.6 ohms/square to 30 ohms/square, and particularly from 2 ohms/square to 20 ohms/square. the A functional layer with a sun protection effect has, for example, good infrared-reflecting properties and/or particularly low emissivities (Low-E).

The functional layer can also be an electrically heatable layer, for example, which provides the pane with a heating function. Such heatable layers are known per se to those skilled in the art. They typically contain one or more, for example two, three or four, electrically conductive layers. These layers preferably contain or consist of at least one metal, for example silver, gold, copper, nickel and/or chromium, or a metal alloy and preferably contain at least 90% by weight of the metal, in particular at least 99.9% by weight of the metal. Such layers have a particularly advantageous electrical conductivity combined with high transmission in the visible spectral range. The thickness of an individual layer is preferably from 5 nm to 50 nm, particularly preferably from 8 nm to 25 nm. With such a thickness, an advantageously high transmission in the visible spectral range and a particularly advantageous electrical conductivity are achieved.

The functional layer can, for example, also be an electrically switchable or controllable functional layer, for example in the form of an SPD (suspended particle device), PDLC (polymer dispersed liquid crystal), electrochromic or electroluminescent functional element. Such functional elements are known per se to a person skilled in the art.

The functional layer is deposited by methods known per se, for example by cathode sputtering supported by a magnetic field, which is particularly advantageous with regard to a simple, rapid, inexpensive and uniform coating of the pane. The cathode sputtering takes place in a protective gas atmosphere, for example argon, or in a reactive gas atmosphere, for example by adding oxygen, a hydrocarbon (for example methane) or nitrogen. However, the functional layer can also be applied by other methods known to those skilled in the art, for example by vapor deposition or chemical vapor deposition (CVD), by atomic layer deposition (ALD), by plasma-enhanced vapor deposition (PECVD) or by wet-chemical methods.

In an advantageous embodiment of the method according to the invention, the (glass) pane contains or consists of flat glass, float glass, quartz glass, borosilicate glass or soda-lime glass. Suitable glasses are known, for example, from EP 0 847 965 B1. ok

The thickness of the disk can vary widely and be adapted to the requirements of the individual case. For example, a disk with a standard thickness of 1.0 mm to 25 mm is used. For example, the thickness is from 0.5 mm to 15 mm, in particular from 1 mm to 5 mm. The size of the disc can vary widely and depends on the use.

The disc can be colorless or colored.

Panes used in practice, in particular windshields of motor vehicles, often have a black masking stripe (black print) in an edge region, which is used to mask structures otherwise recognizable through the pane. In vehicles in particular, the masking strip is used to mask a bead of adhesive for gluing the pane into the vehicle body, so that a harmonious overall impression is created. On the other hand, the at least one masking strip serves as UV protection for the adhesive material used. Continuous exposure to UV light damages the adhesive material and would loosen the connection between the pane and the vehicle body over time. The masking strip is typically applied to the pane using a printing process, in particular a screen printing process. The printing ink is printed onto the pane and then dried or burned in at up to 700 °C, for example. In particular, the masking stripe can merge into dots of different sizes. These so-called screen-printed dots are intended to break up the optically massive impression of the black screen-printed edge.

According to a preferred embodiment of the method according to the invention, before the sacrificial layer is applied to the pane, a preferably black colored layer, in particular a masking strip, made from a material different from the material of the sacrificial layer is applied to the pane in the first region of the pane. The color layer is thus between the sacrificial layer and the pane after the sacrificial layer has been applied. The sacrificial layer partially or completely covers the colored layer. The color layer is particularly advantageously applied in the form of a masking strip (black print) in a circumferential edge area of the pane.

A layer of paint, in particular masking strips (black print), which is applied in particular to the peripheral edge region of the pane, heats up particularly strongly when the pane is heated to bend the pane, at least more than the rest of the pane. This can result in damage to the already sensitive edge area of the pane temperature-related damage occurs. The sacrificial layer can be achieved in a particularly advantageous manner in that the color layer becomes less hot. This is a great advantage of the invention.

The curved pane with a functional layer produced by the method according to the invention is preferably part of glazing which serves to separate an interior space from an exterior environment. The glazing comprises at least one curved pane. The glazing can in principle be of any design, in particular as insulating glazing, in which at least two panes are arranged at a distance from one another by at least one spacer, or as thermally toughened single-pane safety glass or as a laminated pane.

The glazing is preferably designed as a composite pane and comprises a first pane with an outside and inside and a second pane with an inside and outside, which are firmly connected to one another by at least one thermoplastic intermediate layer (adhesive layer). The first pane can also be referred to as the outer pane, the second pane as the inner pane. The surfaces or sides of the two individual panes are usually referred to as side I, side II, side III and side IV from the outside to the inside. In principle, the functional layer can be arranged on any surface of any pane, preferably on an inner surface, ie side II and/or side III. The functional layer thus advantageously has no contact with the atmosphere and is protected from damage and corrosion inside a laminated pane by the thermoplastic intermediate layer.

The thermoplastic intermediate layer contains or consists of at least one thermoplastic, preferably polyvinyl butyral (PVB), ethylene vinyl acetate (EVA) and/or polyethylene terephthalate (PET). However, the thermoplastic intermediate layer can also be, for example, polyurethane (PU), polypropylene (PP), polyacrylate, polyethylene (PE), polycarbonate (PC), polymethyl methacrylate, polyvinyl chloride, polyacetate resin, casting resin, acrylate, fluorinated ethylene propylene, polyvinyl fluoride and/or ethylene Tetrafluoroethylene, or a copolymer or mixture thereof. The thermoplastic intermediate layer can be formed by one or more thermoplastic films arranged one on top of the other, the thickness of a thermoplastic film being, for example, from 0.25 mm to 1 mm. The pane, in particular the glazing, has, for example, a peripheral edge with a width of 2 mm to 50 mm, preferably 5 mm to 20 mm, which is not provided with the functional layer.

According to a further preferred embodiment of the method according to the invention, the sacrificial layer is applied (preferably exclusively) in a peripheral edge area of the pane, which has the advantage that corrosion or changes in the functional layer in the edge area of the pane are prevented.

The invention further extends to a pane made by the method of the invention.

The invention also extends to a method for producing glazing with at least two panes, which comprises the method according to the invention for producing a curved pane coated with a functional layer. In the method for producing the glazing, the at least two panes are connected to one another after the removal of the sacrificial layer and the associated partial removal of the functional layer.

The method according to the invention for producing a glazing preferably serves to produce a laminated pane. To produce a composite pane, at least two panes are connected (laminated) to one another, preferably under the action of heat, vacuum and/or pressure, by at least one thermoplastic adhesive layer. Methods known per se can be used to produce a laminated pane. For example, so-called autoclave processes can be carried out at an increased pressure of about 10 bar to 15 bar and temperatures of 130° C. to 145° C. for about 2 hours. Known vacuum bag or vacuum ring methods work, for example, at about 200 mbar and 130°C to 145°C. The two panes and the thermoplastic intermediate layer can also be pressed in a calender between at least one pair of rollers to form a composite pane. Plants of this type are known for the production of laminated panes and normally have at least one heating tunnel in front of a pressing plant. The temperature during the pressing process is, for example, from 40°C to 150°C. Combinations of calender and autoclave processes have proven particularly useful in practice. Alternatively, vacuum laminators can be used. These consist of one or more heatable and evacuable chambers in which the first pane and second pane within for example about 60 minutes at reduced pressures of 0.01 mbar to 800 mbar and temperatures of 80°C to 170°C.

The invention also extends to a glazing manufactured by the method according to the invention.

The pane or glazing produced according to the invention is preferably used in buildings, especially in the access or window area, as a built-in part in furniture and appliances, or in means of transportation for traffic on land, in the air or on water, especially in trains, ships and motor vehicles used for example as a windshield, rear window, side window and/or roof window.

The various configurations of the invention can be implemented individually or in any combination. In particular, the features mentioned above and to be 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.

The invention is explained in more detail below using exemplary embodiments, reference being made to the attached figures. They show in a simplified representation that is not true to scale:

Fig. 1 is a schematic view of a method of making a disc, the disc being shown in a cross-sectional view;

FIG. 2 shows a schematic top view of a pane with a functional layer; FIG.

Fig. 3 is a schematic view of a modification of the method of manufacturing a disk shown in Fig. 1; and

Figure 4 is a block diagram of the method of making the disc.

1 shows a schematic view of a method for producing a pane 100 coated with a functional layer 105. The pane 100 is shown in a cross-sectional view (section through the two opposite (main) surfaces). First, the pane 100 is provided, which preferably consists of glass, preferably flat glass, float glass, quartz glass, borosilicate glass, soda-lime glass. The pane 100 preferably has a thickness of 0.5 mm to 15 mm, particularly preferably 1 mm to 5 mm.

A sacrificial layer 101 is applied to the pane 100 in a first region 103-1. The area 103 - 1 is a two-dimensional area of one of the two opposite (main) surfaces of the pane 100 which is to be kept free of the functional layer 105 . The sacrificial layer 101 is a polymer layer made of an infrared-curing, ultraviolet-curing or thermosetting polymer. The sacrificial layer 101 preferably consists of a meth-acrylate polymer compound. However, it is also conceivable that it is a polymer layer made from another organic compound. The sacrificial layer 101 adheres to the pane 100 in the first region 103-1. A sacrificial layer 101 of such an organic compound enables rapid and complete combustion during a heat treatment of the disk 100 for bending the disk 100, and generates easily-removed residual substances during its decomposition.

In general, the sacrificial layer 101 can be a layer made of a material that can be applied to the intended first region 103 - 1 of the pane 100 and destroyed in a simple manner by heating and removed again after the layer has been applied.

The functional layer 105 is then applied to a second area 103 - 2 of the pane 100 and the sacrificial layer 101 in the first area 103 - 1 of the pane 100 . The functional layer 105 is applied, for example, by means of cathode sputtering supported by a magnetic field, sprayed on by means of a nozzle, rolled up by means of a roller or printed onto the pane 100 in a screen printing process. The functional layer 105 is, for example, an infrared (IR) reflection layer or a low-E functional layer for thermal radiation at room temperature. The functional layer 105 can, for example, also be an electrically heatable functional layer, an anti-scratch functional layer or an anti-reflection functional layer. The functional layer 105 can be a metal-based functional layer 105 and can include metals such as silver or gold, for example. In general, however, the functional layer 105 can also have any other function. It is essential here that the functional layer 105 is present in one or more partial areas the disc 100 is to be applied. The functional layer 105 has a thickness of 5 nm to 50 nm, preferably 8 nm to 25 nm, for example.

Subsequently, the disk 100 is subjected to a heat treatment to bend the disk 100, with the sacrificial layer 101 being decomposed. The pane 100 can be heated by passing the pane 100 through a heating zone in a processing plant, in which it is heated to a temperature in excess of 500°C. At this temperature, the sacrificial layer 101 of an organic compound, in particular of the methacrylate polymer type, decomposes. In a special case, the heating takes place, for example, for 6 minutes at 640° C., the polymer of the sacrificial layer 101 decomposing at this temperature. The consequence of this is that the functional layer 105 in the first area 103-1 loses contact with the pane 100 and can be removed in a simple manner by cleaning the pane 100, for example by washing it off or dissolving it in a solvent. The functional layer 105 is retained in the second region 103 - 2 of the pane 100 .

The functional layer 105 can be removed from any desired first areas 103 - 1 of the pane 100 by the production method shown. For example, the functional layer 105 can be removed in round or rectangular areas in the center of the pane 100 . On the other hand, the pane 100 can be provided with the functional layer 105 in a targeted manner in one or more second regions 103-2.

FIG. 2 shows a schematic top view of a pane 100 with the functional layer 105 (top view of the surface of the pane) produced by the method from FIG. In the exemplary embodiment in FIG. 2, the functional layer 105 has been removed by removing the sacrificial layer 101 in a peripheral edge region 109 of the pane 100. For example, a peripheral edge region 109 of, for example, 1 to 10 cm around the pane 100 can be produced without the functional layer 105 if the sacrificial layer 101 has been applied in this first region 103-1 beforehand. This design has the advantage that the functional layer 105 does not come into contact with a fastening frame or fastening points when the pane 100 is mounted, and corrosion or changes in the functional layer 105 in this area can therefore be prevented, which occurs in particular with metal-based functional layers 105 when moisture is present . In this way, for example, panes for motor vehicles can be produced in which the functional layer 105 does not come into contact with the body. In general, however, other areas of the pane 100 can also be exempt from a functional layer 105, depending on requirements. After pane 100 has been provided with a functional layer 105 in one or more partial areas (second areas) in this way, it can be connected to one or more other panes to produce glazing, in particular to produce a laminated pane or insulating glazing. In particular, a laminated pane can be used in vehicle construction, for example.

FIG. 3 shows a further schematic view of a method for producing a disc

100 with a functional layer 105. In order to avoid unnecessary repetitions, only the differences from the method of FIG. 1 are explained and otherwise reference is made to the above explanations for FIG.

A black color layer 107 (e.g. black print) is arranged on the pane 100 here in the first area 103-1 and second area 103-2, before the application of the sacrificial layer

101 is applied to the disc 100. The black color layer 107 is located here, for example, in the peripheral edge area 109 of the pane 100 (i.e. the black color layer 107 is designed as a peripheral masking strip, in particular black printing). If the sacrificial layer 101 is removed, the colored layer 107 remains on the pane 100. The sacrificial layer 101 partially covers the colored layer 107, so that the colored layer 107 and thus the pane heat up less in the first region 103-1. In the peripheral edge area 109, the pane can thus be protected from excessive heating when the pane is heated for bending.

4 shows a block diagram of the method for producing the functional layer 105 on a pane 100. In a first step S101, the pane 100 is provided and the sacrificial layer 101 is applied to at least a first region 103-1 of the pane 100. In a second step S102, the functional layer 105 is applied to the sacrificial layer 101, which is arranged in the at least one first region 103-1, and to at least one second region 103-2 of the pane 100, in which there is no sacrificial layer 101 . In a third step S103, the sacrificial layer 101 is removed from the at least one first region 103-1. As a result, the functional layer 105, which is arranged on the sacrificial layer 101, is removed at the same time. In this way, the functional layer 105 is removed again in one or more partial areas of the pane 100, with the functional layer 105 only being on one or more partial areas of the pane 100 remains. In this way, the technical advantage is achieved that different partial areas of the pane 100 can be coated in a targeted manner.

It follows from the above statements that the invention provides an improved method for producing panes in which the functional layer is only provided in partial areas. Coated panes can be produced in a short time by removing the functional layer over a large area. The sacrificial layer can be destroyed by the heat treatment of the pane to bend the pane and can be easily removed from the pane, the functional layer arranged on the sacrificial layer also being removed. Separate heating of the pane to destroy the pane can thus advantageously be dispensed with. Excessive heating of the pane by a black paint layer, in particular black print, in the edge area of the pane can be advantageously avoided by the sacrificial layer applied to the paint layer.

Reference List

100 disc

101 sacrificial layer 103-1 first region

103-2 second area 105 functional layer 107 color layer 109 edge area

Claims

patent claims

1. A method for producing a curved pane (100) with a functional layer (105), with the steps:

Providing (S101) the pane (100) and applying (S101) a sacrificial layer (101) to a first area (103-1) of the pane (100);

Application (S102) of the functional layer (105) to the sacrificial layer (101) and a second area (103-2) of the pane (100);

Removing (S103) the sacrificial layer (101) from the first area (103-1) of the disc

(100), the functional layer (105) being removed from the first region (103-1) of the disc (100), the sacrificial layer (101) containing at least one polymeric organic compound or consisting thereof, the polymeric organic compound having a is a photo- or heat-curable organic compound, and wherein the sacrificial layer (101) is destroyed by heating during a heat treatment for bending the disc (100).

2. The method as claimed in claim 1, in which the sacrificial layer (101) contains or consists of at least one acrylate compound or one meth-acrylate compound.

3. The method according to any one of the preceding claims 1 to 2, wherein the sacrificial layer

(101) is applied to the disc (100) by brushing, rolling, spraying or by means of screen printing.

4. The method according to any one of the preceding claims 1 to 3, wherein the sacrificial layer (101) is removed from the disc (100) by means of a liquid.

5. The method of claim 4, wherein the liquid is a solvent.

6. The method according to any one of the preceding claims 1 to 5, wherein before the application of the sacrificial layer (101) a colored layer (107), in particular a black print, is applied to the pane (100) and then the sacrificial layer (101) is at least partially, in particular completely covering, is applied to the color layer (107).

7. The method according to claim 6, wherein the color layer (107) is applied in a peripheral edge region of the pane (100). 8. The method according to any one of the preceding claims 1 to 7, wherein the functional layer (105) is designed to reflect incident infrared light, or to reflect thermal radiation at room temperature. 9. The method according to any one of the preceding claims 1 to 8, wherein the sacrificial layer

(101) is applied in a peripheral edge area of the pane (100).

10. Curved pane (100) with a functional layer (105), produced by a method according to one of the preceding claims 1 to 9.

Method of manufacturing a glazing unit with at least two panes, comprising the method of manufacturing a curved pane (100) with a functional layer (105) according to any one of the preceding claims 1 to 9, the curved pane (100) after the removal of the sacrificial layer (101) is connected to at least one other disc.

12. Glazing containing a curved pane (100) with a functional layer (105), produced by a method according to claim 11.