Method for producing a composite glass pane

Abstract

The invention relates to a method for producing a composite glass pane (100), having the following steps: - providing a plurality of glass panes (1, 1', 1''), each of which has a thickness of maximally 0.5 mm, - molding the glass panes (1, 1', 1'') by bringing same into contact with at least one contact surface (5, 12) of at least one molding tool (6, 13) of a molding device (7), - producing a stack (8) of the glass panes (1, 1', 1''), wherein an adhesive layer (9, 9') made of an optically clear liquid adhesive is applied onto at least one glass pane (1, 1') such that an adhesive layer (9, 9') is located between each pair of directly adjacent glass panes (1, 1'; 1'' ) in the stack (8) of panes, and - curing the optically clear liquid adhesive in the stack (8) of panes in order to connect the glass panes (1, 1', 1''), whereby the composite glass pane (100) is produced. While the optically clear liquid adhesive is being cured, the stack (8) of panes i) is in contact with the at least one contact surface (5, 12) of the at least one molding tool (6, 13) or ii) is not in contact with the at least one contact surface (5, 12) of the at least one molding tool (6, 13).

Description

[0001] Process for producing a laminated glass pane

[0002] The invention lies in the technical field of industrial pane production and relates to a method for producing a laminated glass pane, the laminated glass pane produced by the method according to the invention and its use.

[0003] Laminated glass panes typically consist of two glass panes and an intermediate layer, which firmly bonds (laminates) the two panes. The intermediate layer is typically made from one or more thermoplastic films, particularly PVB films. Laminated glass panes are typically manufactured by autoclaving, whereby the glass panes are bonded together via the thermoplastic films at high temperature and high pressure. These conditions place considerable stress on the glass panes. Optical distortions can occur in the glass panes as a result of the resulting stresses. This is especially true for formed glass panes, which are usually formed (bent) at high temperatures in special forming devices.To avoid this, the glass panes must have a certain minimum thickness, which, however, means that the weight of the laminated panes cannot be reduced at will.

[0004] Particularly in vehicles, it is desirable for laminated glass panes to be as light as possible due to energy consumption, although the optical quality and stability of the laminated glass panes must not be impaired.

[0005] In contrast, the object of the present invention is to provide an improved process for producing laminated glass panes with high optical quality and relatively low weight. Furthermore, the process should be feasible using production equipment commonly used in the industrial series production of laminated glass panes, allowing for the simple, cost-effective, and reliable production of laminated glass panes with high optical quality and low waste in large quantities.

[0006] These and other objects are achieved according to the invention by a method for producing a laminated glass pane according to the independent patent claim. Advantageous embodiments of the invention emerge from the subclaims. According to the invention, a method for producing a laminated glass pane is shown. The method comprises the following steps, which do not necessarily have to be carried out in the specified order, as will also be apparent from the following description.

[0007] First, several (i.e., two or more) glass panes are provided. The glass panes each have two surfaces (main surfaces) intended for viewing and, in particular, arranged substantially parallel to one another, as well as an edge surface extending between them.

[0008] The glass panes are thin, with a maximum thickness of 0.5 mm. Advantageously, the glass panes have a maximum thickness of 0.4 mm, 0.3 mm, 0.2 mm, or 0.1 mm. The thickness is measured perpendicular to the main surfaces of the glass panes.

[0009] The glass sheets are formed by bending, for which purpose they are brought into contact (touch contact) with at least one contact surface of at least one forming tool of a forming device.

[0010] A stack of vertically stacked glass panes is created from the glass panes. A layer of liquid, optically clear adhesive is applied to at least one glass pane, so that in the finished stack, there is an adhesive layer between each two immediately adjacent glass panes.

[0011] The liquid, optically clear adhesive in the stack of panes is cured, whereby the curing of the liquid, optically clear adhesive firmly bonds the glass panes of the stack of panes to one another, creating the laminated glass pane.

[0012] The method according to the invention provides two alternatives:

[0013] In a first alternative (alternative i), the pane stack is in contact with the at least one contact surface of the at least one molding tool during the curing of the liquid, optically clear adhesive. Preferably, the pane stack is in contact with all contact surfaces used to shape the pane stack or the glass panes. In a second alternative (alternative ii), the pane stack is not in contact with any contact surface of the molding device during the curing of the liquid, optically clear adhesive.

[0014] In the method according to the invention, the glass panes are shaped by bringing them into contact with at least one contact surface of at least one forming tool. Depending on the method, the glass panes can be brought individually (i.e. each) into contact with at least one contact surface of at least one forming tool, so that the glass panes can be individually shaped. It is equally possible for only the stack of panes, i.e. at least one outer glass pane, i.e. the bottommost glass pane and / or the topmost glass pane, of the pane stack, to be brought into contact with at least one contact surface of at least one forming tool, wherein in this case glass panes of the pane stack located between the outer glass panes have no contact with a contact surface of the forming device. Glass panes that do not have contact with a contact surface of the forming device can be formed by adjacent glass panes.

[0015] According to the invention, a laminated glass pane (composite) is produced with glass panes bonded by an optically clear adhesive. The glass panes, in particular directly adjacent glass panes, are not bonded to one another by a thermoplastic interlayer. Since the glass panes are bonded to one another by the optically clear adhesive, it is also unnecessary for the glass panes to be laminated by autoclaving, so that the thin and delicate glass panes are not exposed to the high temperatures and correspondingly high pressure typically associated with autoclaving. This advantageously avoids severe stress on the glass panes during production of the laminated glass pane, and the laminated glass pane can be manufactured with high optical quality.On the other hand, the thin glass panes according to the invention allow for easy shaping at room temperature, so that the laminated glass pane can also be produced with complex shapes, which is particularly advantageous.

[0016] Optically clear adhesives, abbreviated by the acronym OCA (Optically Clear Adhesive), are well known to those skilled in the art. This applies in particular to liquid, optically clear adhesives, abbreviated by the acronym LOCA (Liquid Optically Clear Adhesive), which are also commercially available and freely available from a variety of suppliers. Optically clear adhesives are characterized in particular by their high optical quality and are particularly common where a virtually invisible adhesive layer is required, for example in displays or touch panels. Optically clear adhesives are often used in touch-sensitive displays, for example to bond them to an LCD panel or to bond plastic covers to touch-sensitive displays. Optically clear adhesives are characterized in particular by their high light transmission and the fact that low-distortion viewing is possible.

[0017] The process according to the invention uses an optically clear adhesive in liquid form, which, after curing, firmly bonds the glass panes together. The liquid, optically clear adhesive can, in principle, be of any type, as long as it is sufficiently flowable for application to a glass pane and allows curing in the stack of panes. The liquid, optically clear adhesive can, for example, contain or consist of polyurethane (PU), polyacrylate, polyacetate resin, casting resin, or a copolymer or mixture thereof. Advantageously, the optically clear adhesive consists of a casting resin, particularly based on polyurethane or silicone.

[0018] The liquid, optically clear adhesive used in the process according to the invention is curable, i.e. it can be irreversibly brought into a cured state. Typically, it is a plastic which is brought into a polymer-crosslinked state by curing. This distinguishes the curable adhesive significantly from a thermoplastic (e.g. PVB), which is also optically transparent but can always be softened again (i.e. reversibly) by the application of heat. In contrast, the cured, optically clear adhesive can no longer be brought back into the flowable state once it has cured. The optically clear adhesive is therefore not a thermoplastic.

[0019] Depending on the adhesive used, curing can occur through thermal curing (i.e., application of heat), through electromagnetic radiation, particularly UV radiation, IR radiation, or microwave radiation, through ultrasound, through the application of moisture, or through a chemical reaction between different components (particularly two-component adhesives). The time required for the curing of the liquid, optically clear adhesive can be influenced by the temperature in many curing processes. In particular, curing can be accelerated by the application of heat. Conversely, curing can be slowed by cooling. The curing time can therefore be controlled, for example, by heating or cooling the liquid, optically clear adhesive.

[0020] The two alternatives of the method according to the invention differ significantly in that the pane stack is in contact with the at least one contact surface of the molding device during the curing of the liquid, optically clear adhesive of the pane stack (alternative i), or is not in contact with the at least one contact surface of the molding device (alternative ii). If the pane stack is in contact with the at least one contact surface, this means that at least one outer glass pane (i.e., the bottommost glass pane and / or the topmost glass pane) of the pane stack is in contact with the at least one contact surface of the molding device.

[0021] Contact between a glass pane or stack of panes and a contact surface of the forming device can, in principle, be achieved in any way. For example, contact can be established by placing a glass pane or stack of panes on a contact surface, with only gravity acting on the glass pane or stack of panes, for example. Another possibility for establishing contact is, for example, by suctioning a glass pane or stack of panes onto a contact surface. It is also possible for a contact surface to be positioned against the glass pane or stack of panes, e.g., from above, and thus exert pressure, for example.

[0022] In one embodiment of the method according to the invention, the disk stack is produced in contact with at least one contact surface of at least one molding tool of the molding device.

[0023] For example, the pane stack is created on at least one contact surface of at least one forming tool by successively stacking the glass panes against the direction of gravity on the at least one contact surface. The glass panes are introduced into the forming device one after the other, with a layer of liquid, optically clear adhesive being applied to each of the lower panes of two immediately adjacent glass panes before the upper pane is placed above it.Two process procedures are possible here, whereby in a first process procedure the adhesive layer made of a liquid, optically clear adhesive is applied to a lower glass pane of two immediately adjacent glass panes before they are arranged in the forming device, and whereby in a second process procedure the adhesive layer made of a liquid, optically clear adhesive is applied to a lower glass pane of two immediately adjacent glass panes only after they have been arranged in the forming device.

[0024] It is also possible for the glass panes to be stacked in the direction of gravity to create the pane stack, with the glass panes successively introduced into the forming device being sucked onto at least one contact surface of at least one forming tool, for example. Accordingly, a layer of liquid, optically clear adhesive is applied to each upper glass pane of two immediately adjacent glass panes before the lower glass pane is placed underneath.Here too, two process procedures are possible, whereby in a first process procedure the adhesive layer made of a liquid, optically clear adhesive is applied to an upper glass pane of two immediately adjacent glass panes before they are arranged in the forming device, and whereby in a second process procedure the adhesive layer made of a liquid, optically clear adhesive is applied to an upper glass pane of two immediately adjacent glass panes only after they have been arranged in the forming device.

[0025] In any case, in this embodiment, the glass panes can advantageously be shaped during the production of the pane stack, as soon as they are arranged on the forming tool. Shaping of a glass pane in contact with at least one contact surface takes place directly through the at least one contact surface. Additional glass panes can be formed indirectly via this glass pane.

[0026] In the above embodiment, during the production of the pane stack at least one contact surface of at least one forming tool is in contact with the pane stack, i.e. with the bottom glass pane or the top glass pane of the pane stack, depending on the stacking direction. This does not necessarily have to be all of the contact surfaces used to form the pane stack. For example, at least one further contact surface on the finished pane stack can be brought into contact with the pane stack for shaping purposes. It is understood that the finished pane stack can also be subjected to further shaping. The above embodiment is equally suitable for both alternatives of the method according to the invention, wherein in alternative i) the pane stack remains in the forming device during the curing of the liquid, optically clear adhesive, such that the forming device can contact the glass panes or the top glass pane via at least one contact surface.the stack of panes, and in alternative ii) the stack of panes is removed from the forming device before the liquid, optically clear adhesive has cured, so that no contact surface acts on the glass panes or the stack of panes during curing.

[0027] In an alternative embodiment of the method according to the invention, the pane stack is produced outside the forming device, i.e., the pane stack is produced without contact with a contact surface of a forming tool. The finished pane stack (with unformed glass panes) is then placed in the forming device for forming. To produce the pane stack (outside the forming device), the glass panes are successively arranged on top of one another, with a layer of liquid, optically clear adhesive being applied to the lower glass pane of immediately adjacent glass panes and before the upper glass pane above it is placed.

[0028] The above embodiment is also equally suitable for the two alternatives of the method according to the invention, wherein in alternative i) the stack of panes remains in the molding device during the curing of the liquid, optically clear adhesive so that at least one contact surface can act on the glass panes of the stack of panes, and in alternative ii) the stack of panes is removed from the molding device before the liquid, optically clear adhesive cures.

[0029] The forming device for shaping (bending) the glass panes or the stack of panes can, in principle, be designed in any desired way. Bending devices commonly used in the industrial series production of glass panes can be used here, although this is not absolutely necessary. The glass panes or the stack of panes are particularly advantageously shaped (bent) at room temperature in order to avoid stress on the glass panes at high temperatures, possibly with the exception of locally heated areas of the pane to create a stronger curvature (see below). The thin glass panes used according to the invention advantageously also enable shaping (bending) at room temperature. In one embodiment, the forming device has at least one forming tool which comprises at least one contact surface which is designed such that a glass pane can be contacted over its entire surface. This means that an individual glass pane oran outer glass pane of the pane stack can be contacted over its entire surface.

[0030] In one embodiment, the molding device has at least one molding tool comprising at least one contact surface configured such that a glass pane can only be contacted over part of its surface (i.e., not over its entire surface). This means that an individual glass pane or an outer glass pane of the pane stack can only be contacted over part of its surface.

[0031] In one embodiment, the molding device has at least one first or lower molding tool with at least one contact surface and / or at least one second or upper molding tool with at least one contact surface.

[0032] It is understood that the various configurations of the molding device can be combined with one another, provided they do not represent alternatives.

[0033] In various embodiments, the molding device comprises a lower molding tool with a contact surface which is designed such that a glass pane can be contacted over its entire surface, or a lower molding tool with one or more contact surfaces, each of which is designed such that a glass pane can be contacted (only) over a partial surface, or an upper molding tool with a contact surface which is designed such that a glass pane can be contacted over its entire surface, or an upper molding tool with one or more contact surfaces, each of which is designed such that a glass pane can be contacted (only) over a partial surface, or a lower molding tool with a contact surface which is designed such that a glass pane can be contacted over its entire surface, and an upper molding tool with a contact surface which is designed such that a glass pane can be contacted over its entire surface, or a lower molding tool with a contact surface,which is designed so that a glass pane can be contacted over its entire surface, and an upper forming tool with one or more contact surfaces, each of which is designed so that a glass pane can be contacted (only) over a partial surface, or an upper forming tool with a contact surface which is designed so that a glass pane can be contacted over its entire surface, and a lower forming tool with one or more contact surfaces, each of which is designed so that a glass pane can be contacted (only) over a partial surface, or a lower forming tool with one or more contact surfaces, each of which is designed so that a glass pane can be contacted (only) over a partial surface, and an upper forming tool with one or more contact surfaces, each of which is designed so that a glass pane can be contacted (only) over a partial surface.

[0034] In the above embodiments, the term "a glass pane" refers to an individual glass pane or an outer (top and / or bottom) glass pane of the stack of panes.

[0035] The glass panes or the laminated glass pane can also be provided with complex shapes, whereby pane areas can typically be formed with different radii of curvature.

[0036] In principle, the thin glass panes or the laminated glass pane can be bent at room temperature in the process according to the invention.

[0037] In an advantageous embodiment of the method according to the invention, the glass panes or the stack of panes are locally heated to create a stronger curvature in one or more pane regions. This local heating allows the glass panes to be given stronger curvatures locally, requiring comparatively less force for this. A more strongly curved pane region is understood to be a pane region in which there is a bend with a smaller radius of curvature than in the surrounding area of ​​the pane. Advantageously, the pane regions intended for local heating are provided with a blackening (dark color) so that heat radiation can be better absorbed. Local pane regions can be heated, for example, using an infrared laser or an infrared radiant heater. Such devices for local pane heating are known in the art, so they need not be discussed in detail here.

[0038] In an advantageous embodiment of the method according to the invention, the layer thickness of the glass panes is locally reduced to create a stronger curvature in one or more pane areas. Reducing the pane thickness can be achieved, for example, using a laser or mechanical abrasion (e.g., grinding). Such devices for locally reducing pane thickness are known in the art, so they need not be discussed in detail here. This measure also allows the glass panes to be given stronger curvatures locally, although comparatively less force is required for this.

[0039] In the method according to the invention, a plurality of glass panes are provided. The glass panes are typically separated from one or more glass sheets. This can be done by cutting, for example, using a cutting tool or a laser. It is also possible for the glass sheets to be locally heated along the contours of the glass panes to be separated, followed by breaking out the glass panes. It is also possible for the layer thickness of the glass sheets to be reduced along the contours of the glass panes to be separated, for example, using a laser or an abrasive tool (e.g., by grinding), in order to facilitate the separation of the glass panes.

[0040] In an advantageous embodiment of the method according to the invention, glass fibers are inserted between the glass panes. This measure can further improve the stability of the laminated glass pane. The glass fibers act like a "net" if the laminated glass pane breaks, thus increasing safety, especially for vehicle occupants.

[0041] The laminated glass pane produced by the process according to the invention comprises a plurality of glass panes, each with a maximum thickness of 0.5 mm. Immediately adjacent glass panes are firmly bonded to one another via an adhesive layer (intermediate layer) made of an optically clear adhesive. The laminated glass pane does not contain a thermoplastic intermediary layer for bonding the glass panes.

[0042] The glass panes are preferably made of soda-lime glass, as is common for window panes. However, other types of glass can also be used, such as quartz glass, borosilicate glass, or aluminosilicate glass. The glass panes are preferably transparent. The maximum layer thickness of the glass panes is 0.5 mm. The layer thicknesses of the glass panes can be selected independently of each other. The glass panes can be clear, meaning they have no tint or color, or they can be tinted or colored. The glass panes can be provided with coatings, such as IR coatings or similar.

[0043] The laminated glass pane can be designed to separate an interior space from the outside environment in an opening in a building or a window opening in a vehicle.

[0044] Furthermore, the invention extends to the use of the laminated glass pane according to the invention on buildings or in means of transport for traffic on land, in the air or on water, in particular in motor vehicles, for example as a windscreen, roof window, side window or rear window, in particular in a passenger car or lorry.

[0045] The various embodiments 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. The above statements in connection with the composite pane according to the invention apply analogously to the inventive method for producing the same. Similarly, the statements in connection with the inventive method apply analogously to the composite pane produced by the inventive method.

[0046] The invention is explained in more detail below using exemplary embodiments, with reference to the accompanying figures. They show, in simplified form and not to scale:

[0047] Figure 1 is a perspective view of a glass sheet from which glass panes are cut out,

[0048] Figure 2 is a perspective view of the glass panes of Fig. 1,

[0049] Figure 3 is a schematic perspective view of the glass sheets of Fig. 1 being successively arranged on a contact surface of an exemplary molding tool, Figures 4A-4C are perspective views of the glass sheets of Fig. 1 being used to produce a stack of sheets on the contact surface of the molding tool of Fig. 3, which stack is then cured,

[0050] Figure 5 is a perspective view of the laminated glass pane produced from the pane stack of Fig. 4A-4C,

[0051] Figure 6 shows a cross section through a further embodiment of a forming device with a stack of discs,

[0052] Figure 7 shows a cross section through a further embodiment of a forming device with a stack of discs,

[0053] Figure 8 shows a cross section through a further embodiment of a forming device with a stack of discs,

[0054] Figure 9A-9B perspective views of an embodiment of the laminated glass pane,

[0055] Figure 10 is a flow chart of the process for producing a laminated glass pane.

[0056] Let us first consider Figures 1 and 2. Figure 1 shows a perspective view of the provision of glass panes for producing a laminated glass pane 100, which in this case is, for example, the windshield of a motor vehicle. A plurality of glass panes 1, T, 1" are cut out of a glass sheet 2. In the exemplary embodiment shown here, three glass panes 1, T, 1" are used for producing the laminated glass pane 100, although two or more than three glass panes 1, T, 1" can equally well be used to produce the laminated glass pane 100. The glass sheet 2 consists of soda-lime glass and has, for example, a layer thickness of 0.1 mm, so that the glass panes 1, T, 1" each have a sheet thickness of 0.1 mm.

[0057] The glass panes 1, T, 1", which - corresponding to the outer shape of the windshield to be produced - have an at least approximately trapezoidal shape, are cut out of the glass sheet 2 along contours 3 by means of a cutting tool 4, for example a laser. In Figure 2, the cut-out glass panes 1, T, 1" are shown in a perspective view.

[0058] As schematically illustrated in Figure 3, the glass panes 1, T, 1" are arranged one after the other in stack form on a first or lower contact surface 5 of a first or lower forming tool 6, which is part of a forming device 7. The glass panes 1, T, 1" are stacked in a vertical direction. The glass panes 1, T, 1" are each placed with their underside on the first contact surface 5 or on the already stacked glass panes. The first contact surface 5 is designed here, for example, such that the glass panes 1, T, 1" are supported over their entire surface. Furthermore, the first contact surface 5 here has, for example, a concave shape, although other shapes are also possible.

[0059] The production of a vertically oriented pane stack 8 is explained in more detail below with reference to Figures 4A-4C, which show perspective views of the glass panes 1, T, 1" of Figure 1, which are successively arranged on the first contact surface 5 of the first forming tool 6 according to Figure 3. The pane stack 8 is produced at room temperature.

[0060] As shown in Figure 4A, a first glass pane 1 is first placed with its underside (main surface) onto the first contact surface 5. Subsequently, an adhesive layer 9 made of a liquid, optically clear adhesive is applied to the upper side of the first glass pane 1 facing away from the first contact surface 5. Alternatively, it would also be possible for the adhesive layer 9 to be applied first to the first glass pane 1 and for the first glass pane 1, including the applied adhesive layer 9, to then be placed onto the first contact surface 5. Due to the small pane thickness of 0.1 mm, the first glass pane 1 typically adapts to the concave shape of the first contact surface 5 solely through gravity and is thereby bent into a desired shape. In Figure 4A, the first glass pane 1 with the applied adhesive layer 9 is shown in its still flat (unbent) form for the sake of simplicity.Furthermore, the other glass panes T, 1", which are used for the pane stack 8, are shown schematically.

[0061] As shown in Figure 4B, a second glass pane T is then placed with its underside (main surface) onto the top side of the first glass pane 1 provided with the adhesive layer 9. A further adhesive layer 9' made of a liquid, optically clear adhesive is then applied to the top side of the second glass pane T. Alternatively, it would also be possible for the adhesive layer 9' to be applied first to the second glass pane T and for the second glass pane T, including the applied adhesive layer 9, to then be placed onto the first glass pane 1. Due to the small pane thickness of 0.1 mm, the second glass pane T also adapts to the concave shape of the first contact surface 5 or the shape of the first glass pane 1 solely by gravity and is thereby bent into a desired shape.In Figure 4B, the first glass pane 1 and the second glass pane T, each with the adhesive layer 9, 9' applied, are shown in their still flat (non-bent) form for the sake of simplicity. Furthermore, the additional glass pane 1", used for the pane stack 8, is shown schematically.

[0062] As shown in Figure 40, a third glass pane 1" is then placed with its underside (main surface) onto the upper side of the second glass pane T provided with the adhesive layer 9'. Due to the small pane thickness of 0.1 mm, the third glass pane 1" also adapts to the concave shape of the lower contact surface 5 or the shape of the second glass pane T solely by gravity and is thereby bent into a desired shape.

[0063] The three glass panes 1, T, 1" together with the two adhesive layers 9, 9' form the pane stack 8. In the pane stack 8, the two adhesive layers 9, 9' are each located between the immediately adjacent glass panes, ie the adhesive layer 9 is located between the glass panes 1, T and the adhesive layer 9' is located between the glass panes T, 1".

[0064] In Figure 4C, all glass panes 1, T, 1" or the stack of panes 8 have already been subjected to shaping by bending. As already explained, bending of the glass panes 1, T, 1" can occur solely due to gravity, whereby a compressive force 10, indicated by the thicker arrow, can also be exerted on the glass panes 1, T, 1" from above by means of at least one further contact surface. Such shaping devices are illustrated in connection with Figures 6 to 8.

[0065] As further shown in Figure 40, the liquid, optically transparent adhesive of the two adhesive layers 9, 9' of the (finished) pane stack 8 located on the mold 6 is cured, for which purpose, for example, UV radiation 11 is used here, indicated by the thinner arrows. By curing the liquid, optically transparent adhesive, the glass panes 1, 1', 1' are firmly bonded to one another, and the laminated glass pane 100 is produced.

[0066] Figure 5 shows a perspective view of the laminated glass pane 100 produced from the pane stack 8 by curing the liquid, optically transparent adhesive. The laminated glass pane 100 contains the three glass panes 1, T, 1", as well as the two adhesive layers 9, 9' made of the cured, optically transparent adhesive. The laminated glass pane 100 does not contain a thermoplastic intermediate layer for connecting the glass panes 1, T, 1". As already explained, the laminated glass pane 100 could contain only two glass panes with an intermediate adhesive layer made of a cured, optically transparent adhesive. Likewise, it would be possible for the laminated glass pane 100 to contain more than three glass panes, each with an adhesive layer made of a cured, optically transparent adhesive between two immediately adjacent glass panes.

[0067] The process illustrated in Figures 4A-4C corresponds to the first alternative (alternative i) of the process according to the invention, in which the liquid, optically transparent adhesive of the disk stack 8 is cured with the disk stack 8 arranged in the molding device 7, wherein the disk stack 8 is arranged on the first molding tool 6.

[0068] Likewise, it would alternatively also be possible for the pane stack 8 to first be produced outside the forming device 7 and for the finished pane stack 8 to then be arranged on the first forming tool 6 in order to form the glass panes 1, T, 1" or the pane stack 8. The curing of the liquid, optically transparent adhesive of the adhesive layers 9, 9' of the pane stack 8 then again takes place with the pane stack 8 arranged in the forming device 7. In producing the pane stack 8, the first glass pane 1 is first provided, followed by the application of the adhesive layer 9 to its upper side. Subsequently, the second glass pane T is placed on the upper side of the first glass pane 1 provided with the adhesive layer 9, followed by the application of the further adhesive layer 9' to the upper side of the second glass pane T.It is understood that, alternatively, the second glass pane T, which is already provided with the further adhesive layer 9', can be placed on the first glass pane 1. Subsequently, the third glass pane 1" is placed on the upper side of the second glass pane T, which is provided with the adhesive layer 9'. The process illustrated in Figures 4A-4C could also be modified according to the second alternative (alternative ii) of the process according to the invention, in which the liquid, optically transparent adhesive of the pane stack 8 is cured outside the forming device 7. For this purpose, the pane stack 8 is removed from the forming device 7 after bending the glass panes 1, T, 1" and cured, for example, by UV radiation.Alternatively, it would also be possible for each glass pane 1, T, 1" to be formed individually in the forming device 7 and for the pane stack 8 to be produced outside the forming device 7 and for the liquid, optically transparent adhesive of the pane stack 8 to be cured outside the forming device 7.

[0069] Figures 6 to 8 illustrate various configurations of molding devices, each with a stack of panes 8 accommodated, using schematic cross-sections. Instead of a stack of panes 8, a single glass pane 1, T, 1" could also be accommodated therein.

[0070] In the embodiment of Figure 6, the forming device 7 comprises a first or lower forming tool 6 with a first contact surface 5, and a second or upper forming tool 13 with a second contact surface 12, between which the pane stack 8 is located. The two contact surfaces 5, 12 are each wave-shaped and contact the pane stack 8 (or its outer glass panes) over their entire surface. The first contact surface 5 and the second contact surface 12 are designed to fit snugly. The pane stack 8 can be formed on the first forming tool 6 solely by gravity, whereby the two forming tools 6, 13 with the pane stack 8 in between can also be pressed against one another to form the pane stack 8. For example, the upper forming tool 13 can be pressed against the lower forming tool 6, which is illustrated by an arrow.The molding device 7 of Figure 6 can be operated with the process controls described with reference to Figures 4A-4C.

[0071] In the embodiment of Figure 7, which is a variation of the embodiment of Figure 6, the molding device 7 comprises a first or lower mold 6 with a first or lower contact surface 5, and an upper mold 13 with two second or upper contact surfaces 12, between which the pane stack 8 is located. The first contact surface 5, which is wave-shaped, contacts the pane stack 8 (or its outer glass pane) over its entire surface. The second mold 13 rests only locally against the pane stack 8 with the two second contact surfaces 12 in two pane regions, wherein the two second contact surfaces 12 move into the opposite position to the first contact surface 5 to create wave troughs 14 of the pane stack 8. The two second contact surfaces 12 are each designed in the manner of elongated pressure stamps.The pane stack 8 is placed between the two second contact surfaces 12 to create a wave crest 15 of the lower contact surface 5 due to the thin glass panes 1, T, 1". The pane stack 8 can be bent by gravity alone, whereby the two forming tools 6, 13 with the pane stack 8 in between can also be pressed against one another to form the pane stack 8. For example, the upper forming tool 13 can be pressed against the lower forming tool 6, which is illustrated by an arrow. The forming device 7 of Figure 7 can be operated using the process controls described with reference to Figures 4A-4C.

[0072] In the embodiment of Figure 8, which is a variation of the embodiment of Figure 7, the forming device 7 comprises a first or lower forming tool 6 with three first or lower contact surfaces 5, as well as a second or upper forming tool 13 with two second or upper contact surfaces 12, between which the pane stack 8 is located. The three first contact surfaces 5 and the two second contact surfaces 12 are each designed in the form of elongated pressure stamps and each only locally contact the pane stack 8. The two second contact surfaces 12 serve to create wave troughs 14 of the pane stack 8, and the three first contact surfaces 5 serve to create a wave crest 15 and elevations adjacent to the wave troughs 14, each of which can be understood as part of a wave crest. The glass panes 1, 1, 1 can also be bent in a suitable manner by not making full-surface contact with the forming tools 6, 13.The two molds 6, 13 with the disk stack 8 between them can be pressed against each other to form the disk stack 8. For example, the upper mold 13 can be pressed against the lower mold 6, which is illustrated by an arrow. The molding device 7 of Figure 8 can be operated using the process sequences described with reference to Figures 4A-4C.

[0073] Figures 9A-9B show various perspective views of an embodiment of the laminated glass pane 100. Figure 9A shows a perspective side view, Figure 9B a top view. This embodiment of the laminated glass pane 100 is monolithic (in one piece) and comprises several connected regions which are provided as a windshield 101, a roof window 102 and a rear window 103. The laminated glass pane 100 is already formed into a shape which enables installation on a vehicle. In the regions serving as the windshield 101 and rear window 103, the laminated glass pane 100 has a pane flank 106 on both sides, which are each connected via a pane region 104 which is significantly more curved and has a smaller radius of curvature than the surrounding pane regions, i.e. windshield 101, rear window 103 and pane flank 106.To create the more strongly curved pane areas 104, the laminated glass pane 100 is heated locally, e.g., by means of an infrared laser or an infrared lamp. The local heating by means of heat radiation is supported by a local blackening 105 (e.g., black paint) in the more strongly curved pane areas 104. The laminated glass pane 100 can, for example, be shaped such that the pane area for the rear window 103 has a certain prestress when installed, which supports the opening process.

[0074] Figure 10 illustrates the method according to the invention using a flowchart. Steps a) to d) refer to:

[0075] Step a)

[0076] Providing a plurality of glass panes 1, T, 1", each having a maximum pane thickness of 0.5 mm.

[0077] Step b)

[0078] Forming the glass panes 1, T, 1" by bringing them into contact with at least one contact surface 5, 12 of at least one forming tool 6, 13 of a forming device 7.

[0079] Step c)

[0080] Producing a pane stack 8 from the glass panes 1, T, 1", wherein an adhesive layer 9, 9' made of a liquid, optically clear adhesive is applied to at least one glass pane 1, T, such that in the pane stack 8 there is an adhesive layer 9, 9' between each two immediately adjacent glass panes 1, T; 1".

[0081] Step d)

[0082] Curing the liquid, optically clear adhesive in the pane stack 8 for joining the glass panes 1, T, 1", thereby forming the laminated glass pane 100, wherein the pane stack 8 i) has contact with the at least one contact surface 5, 12 of the at least one forming tool 6, 13 during the curing of the liquid, optically clear adhesive, or ii) has no contact with the at least one contact surface 5, 12 of the at least one forming tool 6, 13.

[0083] The procedural steps do not have to be carried out in the specified order unless this is specified by the procedure.

[0084] From the above, it can be seen that the invention provides an improved method for producing laminated glass panes with thin individual panes, by which laminated glass panes can be produced with high optical quality and low waste due to comparatively low thermal and mechanical stress. The method can be implemented in the industrial series production of laminated glass panes in conventional production facilities, allowing laminated glass panes with high optical quality and low waste to be produced in large numbers simply, cost-effectively, and reliably.

[0085] Reference symbol:

[0086] 1 ,1',1" glass pane

[0087] 2 glass panels

[0088] 3 Contour

[0089] 4 Cutting tool

[0090] 5 first (lower) contact surface

[0091] 6 first (lower) forming tool

[0092] 7 Forming device

[0093] 8 stacks of discs

[0094] 9.9' adhesive layer

[0095] 10 pressure force

[0096] 11 UV radiation

[0097] 12 second (upper) contact surface

[0098] 13 second (upper) forming tool

[0099] 14 wave trough

[0100] 15 Wellenberg

[0101] 100 laminated glass panes

[0102] 101 Windshield

[0103] 102 roof panel

[0104] 103 Rear window

[0105] 104 Disc area

[0106] 105 Blackening

[0107] 106 Disc flank

Claims

Claims 1. A method for producing a laminated glass pane (100), comprising the following steps: Providing a plurality of glass panes (1, T, 1"), each having a maximum thickness of 0.5 mm, Forming the glass panes (1, T, 1") by bringing them into contact with at least one contact surface (5, 12) of at least one forming tool (6, 13) of a forming device (7), Producing a stack of panes (8) from the glass panes (1, T, 1"), wherein an adhesive layer (9, 9') made of a liquid, optically clear adhesive is applied to at least one glass pane (1, T), such that in the stack of panes (8) there is an adhesive layer (9, 9') between each two immediately adjacent glass panes (1, T; 1"), Curing the liquid, optically clear adhesive in the pane stack (8) to join the glass panes (1, 1', 1"), thereby forming the laminated glass pane (100), wherein the pane stack (8) i) has contact with the at least one contact surface (5, 12) of the at least one forming tool (6, 13) during the curing of the liquid, optically clear adhesive, or ii) has no contact with the at least one contact surface (5, 12) of the at least one forming tool (6, 13).

2. A method for producing a laminated glass pane (100) according to claim 1, wherein the stack of panes (8) is produced in contact with at least one contact surface (5, 12) of at least one forming tool (6, 13).

3. A method for producing a laminated glass pane (100) according to claim 1 or 2, wherein the adhesive layer (9, 9') made of a liquid, optically clear adhesive is applied to a respective lower glass pane (1, T) of two immediately adjacent glass panes (1, T, 1") before stacking in the pane stack (8), or the adhesive layer (9, 9') made of a liquid, optically clear adhesive is applied to a respective lower glass pane (1, T) of two immediately adjacent glass panes (1, T, 1") after stacking in the pane stack (8).

4. A method for producing a laminated glass pane (100) according to claim 1, wherein the stack of panes is produced without contact with a contact surface (5, 12) of a forming tool (6, 13).

5. A method for producing a curved laminated glass pane (100) according to one of claims 1 to 4, wherein at least one forming tool (6, 13) comprises at least one contact surface (5) which is designed such that a glass pane (1, 1', 1") can be contacted over its entire surface.

6. A method for producing a curved laminated glass pane (100) according to one of claims 1 to 5, wherein at least one forming tool (6, 13) comprises at least one contact surface (5) which is designed such that a glass pane (1, 1', 1") can be partially contacted.

7. A method for producing a curved laminated glass pane (100) according to one of claims 1 to 6, wherein the forming device (7) has at least one lower forming tool (6) with at least one contact surface (5) and / or at least one upper forming tool (13) with at least one contact surface (12).

8. A method for producing a bent laminated glass pane (100) according to one of claims 1 to 7, wherein the forming device (7) comprises: a lower forming tool (6) with a contact surface (5) which is designed such that a glass pane (1, T, 1") can be contacted over its entire surface, or a lower forming tool (6) with one or more contact surfaces (5), each of which is designed such that a glass pane (1, T, 1") can be contacted over its partial surface, or an upper forming tool (13) with a contact surface (12) which is designed such that a glass pane (1, T, 1") can be contacted over its entire surface, or an upper forming tool (13) with one or more contact surfaces (13), each of which is designed such that a glass pane (1, T, 1") can be contacted over its partial surface, or a lower forming tool (6) with a contact surface (5) which is designed such that a glass pane (1, T, 1") is fully contactable,and an upper mold (13) with a contact surface (12) which is designed such that a glass pane (1, T, 1") can be contacted over its entire surface, or a lower mold (6) with a contact surface (5) which is designed such that a glass pane (1, T, 1") can be contacted over its entire surface, and an upper mold, (13) with one or more contact surfaces (12), each designed such that a glass pane (1, T, 1") can be contacted over part of its surface, or an upper forming tool (13) with a contact surface (12), each designed such that a glass pane (1, T, 1") can be contacted over its entire surface, and a lower forming tool (6) with one or more contact surfaces (5), each designed such that a glass pane (1, T, 1") can be contacted over part of its surface, or a lower forming tool (6) with one or more contact surfaces (5), each designed such that a glass pane (1, T, 1") can be contacted over part of its surface, and an upper forming tool (13) with one or more contact surfaces (12), each designed such that a glass pane (1, T, 1") can be contacted over part of its surface.

9. A method for producing a laminated glass pane (100) according to one of claims 1 to 8, wherein the glass panes (1, T, 1") are locally heated to produce at least one more strongly curved pane region (104).

10. A method for producing a laminated glass pane (100) according to claim 9, wherein the pane regions (104) intended for local heating are provided with a blackening (105).

11. A method for producing a laminated glass pane (100) according to one of claims 1 to 10, wherein the layer thickness of the glass panes (1, T, 1") is locally reduced to produce at least one more strongly curved pane region (104).

12. A method for producing a laminated glass pane (100) according to one of claims 1 to 11, in which a plurality of glass fibers are introduced between the glass panes (1, T, 1").

13. A method for producing a laminated glass pane (100) according to one of claims 1 to 12, wherein the forming of the glass panes (1, T, 1") takes place at room temperature, optionally with the exception of locally heated pane regions (104) to produce a greater curvature.

14. Laminated glass pane (100) produced by the method according to one of claims 1 to 13, which comprises a plurality of glass panes (1, T, 1"), each having a maximum thickness of 0.5 mm, wherein immediately adjacent glass panes (1, T, 1") are each connected to one another via an adhesive layer (9, 9') made of an optically clear adhesive.

15. Use of the laminated glass pane (100) according to claim 14 on buildings or in means of transport for traffic on land, in the air or on water, in particular in motor vehicles, for example as a windscreen, rear window, side windows and / or roof window.

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