Layer composite and method for the production thereof

Abstract

The invention relates to an improved layer composite, e.g. which can be used as a multi-panel composite safety glass, and a method for the preferably bubble-free production thereof. The layer composite comprises a substrate (10), a cover layer (40) and a polymer layer (30) arranged in between, wherein the polymer layer is connected to the substrate (10) and the cover layer (40) by means of adhesive layers (20, 21). The cover layer (40) has a light transmission level, according to DIN EN ISO 410, of ≥ 50%. The polymer layer (30) has a tensile strength, according to DIN EN ISO 527, of ≥ 30 MPa and the adhesive layers (20, 21) are layers of a cured reactive adhesive and / or radiation-curing adhesive.

Description

[0001] Layered composite and process for its production

[0002] The present invention relates to a layered composite comprising a substrate, a cover layer and a polymer layer arranged therebetween, wherein the polymer layer is bonded to the substrate and the cover layer by means of adhesive layers.

[0003] Laminated safety glass, consisting of two rigid glass layers laminated together, is typically bonded today using heat-laminatable polyvinyl butyral (PVB) or ethylene-vinyl acetate copolymer (EVA) films. For example, EP 3438206 A1 describes a thermoplastic resin film and a laminate containing glass sheets. Specialized products with an ionoplast interlayer are marketed under the SentryGlas brand, among others. It is claimed that such an ionoplast interlayer is more durable and stiffer than PVB interlayers.

[0004] EP 2986451 B1 discloses a method for forming a laminated glass structure, the method comprising: inserting a continuous ribbon of flexible glass substrate having a thickness of no more than 0.3 mm into a non-glass substrate material, wherein the non-glass substrate material has a coefficient of thermal expansion (CTE) greater than that of the flexible glass substrate; laminating the flexible glass substrate to the non-glass substrate material at an elevated temperature; and controlled cooling of the laminated glass structure to introduce a compressive stress across a thickness of the flexible glass substrate, wherein the flexible glass substrate has a compressive strength of at least 40 MPa across the thickness of the flexible glass substrate.

[0005] US 2003 / 0124296 A1 relates to a thermoplastic polymer film having a haze of at least 4%, the film being suitable in a laminate barrier for protection against the penetration of objects into the laminate with sufficient force on impact to break glass, the laminate comprising at least one glass layer and comprising: the thermoplastic polymer film self-adhesively attached directly to the glass layer, the thermoplastic polymer film consisting essentially of an ionomeric polymer and a UV-light absorbing material, and the laminate being capable of withstanding repeated or prolonged loads without failure, even after breakage of the glass.

[0006] US 5,352,528 discloses a composite pane with at least one glass pane and at least one film of PVC-containing plastic with an ageing- and weather-resistant transparency and an energy absorption suitable for a safety pane, wherein an adhesive film is arranged between the glass pane and the plastic film, wherein the adhesive film has a stronger adhesion to the glass than to the plastic film, and wherein the adhesive film comprises a terpolymer comprising ethylene, either vinyl acetate or acrylic ester, and maleic anhydride.DE 10 2018 124 601 A1 describes a glass construction for parapet and / or railing glazing or glass supports with a composite element designed as a glass laminate, which consists of at least two glass panes connected by an adhesive intermediate layer made of plastic. At least one edge of the composite element has an edge protector that is connected, at least in some areas, to the respective end faces of the at least two glass panes of the glass laminate in such a way that the intermediate layer is protected from moisture. Reference is also made to WO 2020 / 069983 A1.

[0007] WO 2014 / 086610 A1 relates to a laminate comprising two rigid substrates and an adhesive film arranged therebetween, wherein at least one of the rigid substrates is transparent, wherein the thickness of the adhesive film is not more than 80 μm and the adhesive film comprises at least one adhesive layer made of an adhesive to which one or more plasticizers are added, of which at least one plasticizer is a reactive plasticizer, wherein the plasticizer proportion in the adhesive is at least 15% by weight in total and the proportion of reactive plasticizer in the adhesive is at least 5% by weight.

[0008] WO 2020 / 064297 A1 discloses a laminated glass pane and a method for producing the same. The laminated glass pane comprises two glass or polycarbonate panes and at least one polymer film or film laminate bonded between them, and an electronic functional unit arranged between them. A cutout of the polymer film or film laminate is provided in a partial surface area of ​​the laminated glass pane, and a completely prefabricated electronic functional module is accommodated in the cutout, which has a thickness that is at most equal to the thickness of the polymer film or film laminate. The electronic functional module has the shape of a flat prism, in particular a flat cuboid, or a flat circular disk, and the two main surfaces of the flat prism or flat circular disk are coated with adhesive for bonding the electronic functional module between the glass or polycarbonate panes.

[0009] WO 2015 / 097111 A1 describes a method for producing a layered composite, wherein the layered composite comprises a substrate, a cover layer, and an adhesive layer arranged between the substrate and the cover layer. The adhesive layer contacts the substrate and the cover layer at least partially. The method comprises the step of pivoting the substrate and the cover layer towards one another such that the distance between the upper substrate edge and the upper cover layer edge decreases and the adhesive is moved in the direction of the upper substrate edge and the upper cover layer edge. This is carried out such that during at least part of step B), the angle bisector (100°) of the angle α forms an angle of > -45° to < 45° with respect to the vertical.

[0010] The utility model DE 202013105933 U1 discloses a layered composite comprising a substrate, a cover layer, and a cured adhesive layer arranged between the substrate and the cover layer, wherein the adhesive layer at least partially contacts the substrate and the cover layer. The substrate comprises a mineral material, the cover layer comprises a glass, an electrical functional unit is arranged between the substrate and the cover layer, and in the layered composite, the average content of gas bubbles enclosed in the adhesive layer with a maximum extension of > 100 pm is less than 100 gas bubbles / m 2 .

[0011] The present invention has set itself the object of providing an improved layered composite, such as can be used, for example, as multi-pane safety laminated glass, and a process for its production with as little bubbles as possible.

[0012] According to the invention, the object is achieved by a layered composite according to claim 1 and a method according to claim 9. Advantageous further developments are specified in the subclaims. They can be combined in any desired way unless the context clearly indicates otherwise.

[0013] The layered composite according to the invention has the advantage that significantly higher composite strengths can be achieved without increasing the composite's weight. These strengths are primarily a combination of compressive strength and puncture resistance. If the same strengths are required, the composite can be realized with a lower overall weight.

[0014] The thermal resistance of the laminated composite can also be significantly increased compared to the conventional thermoplastic hot-melt adhesive films mentioned above. The lower weight of the polymer layer can also positively influence the fire behavior. Furthermore, the process according to the invention has the advantage of reducing the moisture sensitivity of the laminate compared to EVA, PVB, or ionomer interlayers. In addition, the production time for laminated glass can be reduced from several hours to just a few minutes. Energy consumption is also reduced, as the laminate can be produced at room temperature or slightly elevated temperatures, thus eliminating the need for an autoclaving process.

[0015] The invention is explained in more detail by the following drawings, but is not limited thereto. They show:

[0016] FIG. 1 shows a layered composite according to the invention

[0017] FIG. 2 shows another layer composite according to the invention

[0018] FIG. 3 shows another layer composite according to the invention

[0019] FIGS. 4-6 Arrangements in a method for producing a layered composite according to the invention FIG. 1 shows a layered composite comprising a substrate 10, a cover layer 40 and a polymer layer 30 arranged therebetween, wherein the polymer layer is connected to the substrate 10 and the cover layer 40 by means of adhesive layers 20, 21. According to the invention, it is provided that the cover layer 40 has a light transmittance according to DIN EN ISO 410 of > 50%, the polymer layer 30 has a tensile strength according to DIN EN ISO 527 of > 30 MPa and the adhesive layers 20, 21 are layers of a cured, for example multi-component, reactive adhesive and / or radiation-curing adhesive.

[0020] Examples of suitable materials for the substrate 10 are mineral materials or glass. Suitable mineral materials include, for example, stone, natural stone, concrete, gypsum, and the like. "Natural stone" is generally understood to mean all rocks found in nature. Preferred natural stones are granite, marble, quartz, quartz composite, travertine, sandstone, slate, and agate. Examples of suitable glasses are E-glass, S-glass, M-glass, quartz glass, borosilicate glass, crown glass, soda-lime glass, float glass, flint glass, and / or lead crystal glass. The glass for the substrate 10 can be colored or uncolored. Preferably, the thickness of the substrate 10 is > 1 mm to < 40 mm, and more preferably > 2 mm to < 20 mm.

[0021] Examples of suitable materials for the cover layer 40 are polymethyl (meth)acrylate, polycarbonate, and glass. Examples of suitable glasses are E-glass, S-glass, M-glass, quartz glass, borosilicate glass, crown glass, soda-lime glass, float glass, flint glass, and / or lead crystal glass. The glass for the cover layer 40 can be colored or uncolored. Preferably, the thickness of the cover layer 40 is >1 mm to <40 mm, and more preferably >2 mm to <20 mm.

[0022] The cover layer 40 has a calibration transmittance according to DIN EN ISO 410 of > 50% and can thus be characterized as at least partially transparent. The light transmittance is preferably > 60%, more preferably > 70%, particularly preferably > 80%, and most preferably > 90%. According to one embodiment, the substrate 10 can also have the aforementioned light transmittances (> 50%, preferably > 60%, more preferably > 70%, particularly preferably > 80%, most preferably > 90%). According to a further embodiment, the polymer layer 30 can also have the aforementioned light transmittances. According to a further embodiment, the adhesive layers 20, 21 can also have the aforementioned

[0023] Light transmittances. According to a further embodiment, the layered composite as a whole has the aforementioned light transmittances. In particular, the light transmittance of the layered composite can be > 90%.

[0024] The polymer layer 30 can be continuous or discontinuous. It is preferred that the surface area of ​​the polymer layer, defined by its outer perimeter, be equal to or larger than the surface area of ​​the substrate 10 and / or the cover layer 40. For example, the layered composite can be trimmed at the edges after its production so that the surfaces of the substrate 10, polymer layer 30, and cover layer 40 are equal.

[0025] The polymer layer 30 has a tensile strength according to DIN EN ISO 527 of >30 MPa. Preferably, the tensile strength is >40 MPa to <300 MPa, and more preferably >50 MPa to <250 MPa. For the purposes of the present invention, it is assumed that the tensile strength of the polymer layer 30 in the layered composite can be equated with the tensile strength of a free layer of the same material. Thus, for example, the data sheet of a polymer film can be consulted to select a polymer layer 30 suitable according to the invention. If the tensile strengths of the polymer layer differ in the machine direction and in the transverse direction, the lower of the two values ​​is selected.

[0026] The thickness of the polymer layer 30 can be > 0.05 mm to < 4 mm, preferably > 0.10 mm to < 3 mm, and more preferably > 0.15 mm to < 2 mm. The polymer layer 30 can be formed in one piece or in multiple pieces. Multi-piece polymer layers can be realized, among other things, by laminated film stacks.

[0027] The adhesive layer 20 is the adhesive layer that bonds the substrate 10 to the polymer layer 30. The adhesive layer 21 bonds the cover layer 40 to the polymer layer 30. It is preferred that the same adhesive be present in the adhesive layers 20 and 21. The thickness of an adhesive layer 20 and / or 21 can be >1 μm to <650 μm (preferably >2 μm to <400 μm, more preferably >3 μm to <150 μm, particularly preferably >5 μm to <50 μm).

[0028] The adhesive layers 20, 21 are layers of a cured reactive adhesive and / or radiation-curing adhesive. The adhesives are preferably transparent and are in particular two-component adhesives such as epoxy, (meth)acrylate, and polyurethane resins, as well as radiation-curing adhesives such as (meth)acrylates and urethane (meth)acrylates. Dual-cure adhesives, in which radiation curing and non-radiation curing occur side by side or consecutively, are also suitable.

[0029] Preferably, in the layered composite according to the invention, the average content of gas bubbles enclosed in the adhesive layers 20, 21 with a maximum extension of > 100 pm is less than 100 gas bubbles / m 2The gas bubble content can be determined, for example, by visual inspection and counting the gas bubbles. Automated procedures that check the layer bond using a camera and image processing software are also conceivable. The average content of these gas bubbles is preferably less than 10 gas bubbles / m 2 , more preferably less than 1 gas bubble / m 2 The lower the gas bubble content, the higher the quality of the layered composite is perceived by the end user. According to a further embodiment, the layered composite can comprise several polymer layers 30. For example, the layered composite can have the following structure, with the individual layers being designated by their reference numerals in FIG. 1 for simplicity: 10 - [20 - 30] n - 21 - 40, where [20 - 30] nwhere n represents the repeating unit of adhesive layer 20 and polymer layer 30, and n represents the number of repeating units. For example, n can take values ​​of 2, 3, 4, 5, 6, 7, 8, 9, or 10.

[0030] According to one embodiment, the cured adhesive of the adhesive layers (20, 21) has an elongation at break according to DIN EN ISO 527 of > 10%. The elongation at break is preferably > 10% to < 600%, more preferably > 50% to < 500%, and particularly preferably > 200% to < 460%. Without being bound to any theory, it is assumed that with such elongations at break, an optimum of two opposing effects can be achieved. Adhesive layers that are too stretchy are undesirable from the point of view of heat resistance, and layers that are too stretchy result in poorer fixation of adhering glass splinters.

[0031] According to a further embodiment, the cured adhesive of the adhesive layers 20, 21 has a tensile strength according to DIN EN ISO 1465 of > 2 MPa. Preferably, the tensile strength value is > 4 MPa to < 50 MPa, and more preferably > 6 MPa to < 35 MPa.

[0032] It is particularly preferred if the cured adhesive of the adhesive layers 20, 21 simultaneously has the described elongations at break and tensile strengths.

[0033] According to a further embodiment, the polymer layer 30 comprises a polyester polymer, thermoplastic polyurethane polymer, or a polycarbonate polymer. Preferably, the polymer layer 30 comprises a stretched, particularly preferably a biaxially stretched, polyester film. Such polyester films can have softening temperatures of 200°C and more. In this way, the thermal stability of the layered composite is increased in the event of a fire, particularly compared to EVA and PVB laminated glass. Biaxially stretched polyester films can achieve tensile strengths of 150 MPa and more. Such high tensile strengths have a favorable effect on the mechanical stability of the layered composites, particularly in situations such as storms where debris is thrown through the air.

[0034] According to a further embodiment, the polymer layer 30 is formed as a film without cutouts, as a film with one or more cutouts 31, as a woven fabric, or as a nonwoven. The case in which the polymer layer 30 is formed as a film without cutouts can be seen in FIG. 1. FIG. 2 shows the case in which the polymer layer 30 is formed as a film with cutouts 31. The cutouts 31 create an additional, continuous adhesive bond between the substrate 10 and - 1 -

[0035] Cover layer 40 is formed. This can lead to increased strength and special optical effects. If the adhesive and polymer layer have the same refractive index, the recesses become invisible.

[0036] The recesses 31 can be arranged regularly or randomly. Examples of cross-sections of the recesses 31 are round, oval, square, rectangular, and strip-shaped. The recesses 31 can, for example, make up >1% to <70%, and more preferably >5% to <50%, of the total area of ​​the film forming the polymer layer 30. By designing the film as a woven or nonwoven fabric, continuous adhesive bonds between the substrate 10 and the cover layer 40 can also be realized.

[0037] According to a further embodiment, at least a portion of the polymer layer 30 protrudes from the layered composite. This is depicted in FIG. 3. For example, the polymer layer 30 can protrude by >0.5 cm to <20 cm, and more preferably >1 cm to <10 cm.

[0038] The protruding portion of the polymer layer 30 can be used for mounting and / or sealing the composite layer in a frame, for example, a window frame. This has the advantage of increasing the pressure resistance of a window, for example, in the case of extreme wind loads.

[0039] According to a further embodiment, the polymer layer 30 is not post-crosslinkable or post-crosslinked. Thus, ionomer films, in particular, are excluded. Post-crosslinking refers in particular to thermal post-crosslinking, although photochemical post-crosslinking is also included.

[0040] According to a further embodiment, the layer composite has at least one of the following properties:

[0041] Substrate 10 and cover layer 40 are, independently of one another, glass layers with a thickness of >1 mm to <40 mm; the polymer layer 30 has a thickness of >0.05 mm to <4 mm (preferably >0.1 mm to <2 mm, more preferably >0.15 mm to <1 mm); the sum of the thicknesses of polymer layer 30 and adhesive layers (20, 21) is >0.06 mm to <5.3 mm (preferably >0.1 mm to <2.1 mm), and the thickness of an adhesive layer (20, 21) is >1 pm to <650 pm (preferably >2 pm to <400 pm, more preferably >3 pm to <150 pm, particularly preferably >5 pm to <50 pm). The method according to the invention is explained with reference to FIGS. 4 to 6. The process for producing a layered composite according to the invention comprises:

[0042] A) Providing an arrangement comprising a substrate 100 and a cover layer 200, wherein the substrate 100 comprises a first substrate side 110 with an upper substrate edge 120, viewed in the vertical direction, a lower substrate edge 130, viewed in the vertical direction, a first substrate side edge 140, and a second substrate side edge 150 opposite the first substrate side edge; the cover layer 200 comprises a first cover layer side 210 with an upper cover layer edge 220, viewed in the vertical direction, a lower cover layer edge 230, viewed in the vertical direction, a first cover layer side edge 240, and a second cover layer side edge 250 opposite the first cover layer side edge; the first substrate side 110 and the first cover layer side 210 face each other at an angle α in the arrangement, and an angle bisector 1000 of the angle α is formed;the upper substrate edge 120 and the upper cover layer edge 220 lie opposite one another in the arrangement; the lower substrate edge 130 and the lower cover layer edge 230 lie opposite one another in the arrangement; the first substrate side edge 140 and the first cover layer side edge 240 lie opposite one another in the arrangement; the second substrate side edge 150 and the second cover layer side edge 250 lie opposite one another in the arrangement; in the arrangement, the distance between the upper substrate edge 120 and the upper cover layer edge 220 is greater than the distance between the lower substrate edge 130 and the lower cover layer edge 230; in the arrangement, a first seal 500 is provided between the lower substrate edge 130 and the lower cover layer edge 230, which seal prevents the escape of fluids between the lower substrate edge 130 and the lower cover layer edge 230;in the arrangement between the first substrate side edge 140 and the first cover layer side edge 240, a second seal 510 is provided, which prevents the escape of fluids between the first substrate side edge 140 and the first cover layer side edge 240; in the arrangement between the second substrate side edge 150 and the second cover layer side edge 250, a third seal 520 is provided, which prevents the escape of fluids between the second substrate side edge 150 and the second cover layer side edge 250; so that the arrangement forms a container open on one side for receiving fluids, and in this container there is also a curable adhesive 310;

[0043] B) pivoting the substrate 100 and the cover layer 200 towards each other so that the distance between the upper substrate edge 120 and the upper cover layer edge 220 decreases and the adhesive 310 is moved towards the upper substrate edge 120 and the upper cover layer edge 220;

[0044] C) Allow the adhesive 310 to cure.

[0045] In the arrangement according to A), a polymer layer 400 with a tensile strength according to DIN EN ISO 527 of > 30 MPa is further present between substrate 100 and cover layer 200. Preferably, the tensile strength is > 40 MPa to < 300 MPa, and more preferably > 50 MPa to < 250 MPa.

[0046] Details regarding the materials and dimensions of the substrate, cover layer, adhesive, and polymer layer have already been mentioned in connection with the layered composite according to the invention and will not be repeated here. This information applies equally to the process according to the invention.

[0047] According to one embodiment of the method, the temperature of the polymer layer (400) is <50°C at least during steps A), B), and C). Preferably, the temperature is <40°C and more preferably <30°C. This means that no autoclaving process, as would be required for thermal crosslinking of EVA or ionomer films, needs to be part of the method.

[0048] According to a further embodiment of the process, no heating of the layered composite to a temperature of > 100 °C is carried out after step C). Preferably, heating is not carried out to < 80 °C, and particularly preferably, heating is not carried out to < 60 °C. This also reflects that no autoclaving process, as would be required for the thermal crosslinking of EVA or ionomer films, needs to be part of the process.

[0049] According to a further embodiment of the method, at least at the beginning of the pivoting in step B), the adhesive 310 has a viscosity at 20 °C according to DIN EN 12092 of < 50,000 mPas. Preferably, the viscosity is > 10 mPas to < 20,000 mPas, and more preferably > 50 mPas to < 10,000 mPas.

[0050] According to a further embodiment of the method, the polymer layer 400 comprises a polyester polymer, thermoplastic polyurethane polymer or a polycarbonate polymer.

[0051] According to a further embodiment of the method, the polymer layer 400 is formed as a film without recesses, as a film with one or more recesses 31 (see FIG. 2), as a woven fabric or as a nonwoven fabric.

[0052] According to a further embodiment of the method, the polymer layer 400 is not post-crosslinkable or post-crosslinked. Thus, ionomer films, in particular, are excluded. Post-crosslinking refers in particular to thermal post-crosslinking, although photochemical post-crosslinking is also included.

[0053] FIG. 4 shows an arrangement for use in the method according to the invention, which is intended to explain some spatial relationships and geometric definitions. For clarity, however, no adhesive or polymer layer is depicted in the arrangement in FIG. 4.

[0054] As already described, the method according to the invention provides an arrangement of a substrate and a cover layer. The method for constructing this arrangement, for example, the individual steps and their sequence, is not specified.

[0055] In the arrangement shown in FIG. 4, a substrate 100 and a cover layer 200 are present. The substrate has a first substrate side 110. This first substrate side 110 will later be bonded to the corresponding first cover layer side 210 of the cover layer 200.

[0056] Various edges are defined on the respective substrate and cover layer sides. The first substrate side 110 has an upper substrate edge 120, viewed in the vertical direction (against gravity), and an opposite, lower substrate edge 130, viewed in the vertical direction. In the case shown in FIG. 4, these edges run horizontally. Adjacent to the upper and lower substrate edges 120, 130 are the substrate side edges 140 and 150, which here run vertically.

[0057] Likewise, the first cover layer side 210 has an upper cover layer edge 220, a lower cover layer edge 230, and two cover layer side edges 240, 250, which are opposite one another. The first substrate side 110 and the first cover layer side 210 face each other, so that the substrate 200 and the cover layer 210 form an approximately "V"-shaped structure. The upper substrate edge 120 and the upper cover layer edge 220, as well as the lower substrate edge 130 and the lower cover layer edge 230, are opposite one another. Likewise, the first substrate side edge 140 and the first cover layer side edge 240, as well as the second substrate side edge 150 and the second cover layer side edge 250, are opposite one another. In accordance with the description of the structure as "V-shaped," the distance between the upper substrate edge 120 and the upper cover layer edge 220 is greater than the distance between the lower substrate edge 130 and the lower cover layer edge 230.

[0058] Through the use of sealants, the "V-shaped structure" becomes a container open at the top, or, figuratively speaking, a trough. These sealants seal the gaps between the opposite edges of substrate 100 and cover layer 200.

[0059] Here, a second seal 510 seals between the first substrate side edge 140 and the first cover layer side edge 240, and a third seal 520 seals between the second substrate side edge 150 and the second cover layer side edge. The fact that the arrangement in the inventive method is open on one side and, in particular, "open at the top" means that escaping adhesive finds enough space to escape the gap formed between substrate 100 and cover layer 200. Included in the case of being open on one side is that the arrangement is covered all around, but the adhesive can escape, as mentioned above.

[0060] FIG. 5 shows the arrangement from FIG. 4 in a view obliquely from below. The substrate 100 and the cover layer 200, the side edges 140, 150, 240, and 250, as well as one of the lateral seals 520, are again visible. Also visible is the first seal 500, which prevents the escape of fluids (in particular adhesive) between the lower edge of the substrate and the cover layer. The first seal 500, second seal 510, and third seal 520 are configured, for example, by overlapping, such that the arrangement as a whole represents a container open at the top, which can hold an adhesive. However, they can also be combined and, for example, be present as a single sealing piece.

[0061] FIG. 6 shows a cross-sectional view of the arrangement shown in FIG. 4 and FIG. 5, wherein a curable adhesive 310 and a polymer layer 400 are now also present in the formed, upwardly open container. The adhesive is thus already at least partially in contact with the first substrate side 110 and the first cover layer side 210. The polymer layer 400 can be introduced into the arrangement according to FIGS. 4 and 5 before the adhesive is introduced. However, it is also possible to introduce the adhesive first and then introduce the polymer layer into the arrangement.

[0062] The adhesive is prevented from escaping from the container by the seals present. Due to the cross-sectional view, the seal 520 from FIGS. 4 and 5 is not shown in FIG. 6. Whether the adhesive 310 is poured into the fully constructed "trough" comprising substrate 100, cover layer 200, and seals 500, 510, 520, or whether it is already present on the substrate and / or cover layer and the "trough" is then constructed, is irrelevant for the method according to the invention. An angle a is formed between the first substrate side 110 and the first cover layer side 210. Accordingly, an angle bisector 1000 can be constructed.

[0063] In the method according to the invention, the substrate 100 and the cover layer are pivoted toward each other. In this process, at least the distance between the upper substrate edge 120 and the upper cover layer edge 220 increases. Figuratively speaking, this can be compared to closing a book. The "spine" is formed by the lower edges 130, 230 and the lower first seal 500. The pivoting is symbolized in FIG. 6 by the two curved arrows. The pivoting of the substrate 100 and the cover layer 200 toward each other results in the adhesive arranged between them being pressed further and further along the gaps between the substrate 100, the polymer layer 400, and the cover layer 200. Thus, it is also moved further and further toward the upper substrate edge 120 and the upper cover layer edge 120.

[0064] In the method according to the invention, it can be provided that during at least part of step B (pivoting), the bisector 1000 of the angle α assumes an angle of > -45° to < 45° relative to the vertical. In this way, it is ensured that the opening of the arrangement always points upward, so that air bubbles trapped in the adhesive can also rise upward and leave the gap between substrate 100 and cover layer 200. Preferably, the bisector 1000 of the angle α assumes an angle of > -30° to < 30°, more preferably > -15° to < 15° relative to the vertical. This can then be referred to as a "standing bond" between the substrate 100 and the cover layer 200.

[0065] In FIG. 6, the angle bisector 1000 has an angle of 0° to the vertical. In this case, negative angles mean that the angle bisector 1000 is tilted to the left; positive angles symbolize an inclination in the other direction. Therefore, the sign of the angle of inclination also depends on the viewing point. The lower substrate edge 130 and the lower cover layer edge 230 do not necessarily have to touch. Because the first seal 500 is present, they can also be arranged at a distance from each other. Their spacing can be selected taking into account the desired thickness of the adhesive layer in the finished layer composite.

[0066] The curing of the adhesive 310 can be achieved, for example, by UV exposure or by allowing a 2-component adhesive to react. Examples

[0067] The present invention is further described by the following examples, but is not limited thereto.

[0068] The tensile strengths (DIN EN ISO 527) of the films used were:

[0069] The adhesives used are listed below. The specified elongations at break (DIN EN ISO 527) refer to the cured adhesive.

[0070] All tests were conducted using round, clear float glass panes (2 mm thick / 10 cm diameter) and / or foils or films (of varying thickness, 10 cm diameter). Bonding to the glass panes was carried out using a UV-curing adhesive (adhesive layer thickness approximately 0.005 mm). Curing was carried out for 20 minutes using a 2000-watt Hönle UVA lamp (UVA Spot 200) at a distance of 75 cm. This corresponded to a UV irradiance of 50 mW / cm. 2 .

[0071] To determine the compressive strength and puncture strength, the specimens were clamped in a steel cylinder with an outer diameter of 10 cm and an inner diameter of 8.4 mm. Using a screw press with a rounded Teflon head (2 cm diameter), the specimens were pressed in, and the weight exerted on them by the Teflon head was measured. The lowering speed of the Teflon head was 15 cm / min. The compressive strength value was read when the specimen fractured or splintered. The puncture strength value was read when the punch penetrated the specimen.

[0072] It was observed that for samples up to approximately 1 mm thick, the puncture resistance behaved largely linearly as a function of layer thickness during the test procedure. This made it possible to convert the puncture resistance of films and adhesive layers to a standard thickness (here: 0.25 mm) to make the results more comparable. 1. Results of the tests on glass panes without intervening films

[0073] In the test with the glass panes bonded with UV adhesive 4, a fragmentation of the glass panes into many individual pieces was observed. Such loose pieces occurred only to a very small extent in the parallel test using UV adhesive 3. 2. Results of the tests on cured adhesive films and on polymer films (each on a

[0074] Thickness of 0.25 mm standardized)

[0075] 3. Results of the tests on multilayer composites. The multilayer composites had the following structure: glass / cured UV adhesive 3 / polymer film / cured UV adhesive 3 / glass. 4. Results of testing on a layered composite with the structure: glass / cured UV adhesive

[0076] 4 / biaxially oriented polyester film / cured UV adhesive 4 / glass

[0077] The test setup corresponded to the compressive strength and puncture resistance tests mentioned above. In the test with the laminate bonded with UV adhesive 4, fragmentation of the glass panes into numerous loose fragments was observed. Such loose fragments occurred only to a very small extent in the parallel test using UV adhesive 3.

Claims

Patent claims 1. Layered composite comprising a substrate (10), a top layer (40) and an intermediate polymer layer (30), wherein the polymer layer is bonded to the substrate (10) and the top layer (40) by means of adhesive layers (20, 21), characterized in that the top layer (40) has a light transmittance according to DIN EN ISO 410 of > 50%, the polymer layer (30) has a tensile strength according to DIN EN ISO 527 of > 30 MPa and the adhesive layers (20, 21) are layers of a cured reactive adhesive and / or radiation-curing adhesive.

2. Layer composite according to claim 1, wherein the cured adhesive of the adhesive layers (20, 21) has an elongation at break according to DIN EN ISO 527 of > 10%.

3. Layer composite according to claim 1 or 2, wherein the cured adhesive of the adhesive layers (20, 21) has a tensile strength according to DIN EN ISO 1465 of > 2 MPa.

4. Layered composite according to one of claims 1 to 3, wherein the polymer layer (30) comprises a polyester polymer, a thermoplastic polyurethane polymer or a polycarbonate polymer.

5. Layers bonded according to one of claims 1 to 4, wherein the polymer layer (30) is formed as a film without cutouts, as a film with one or more cutouts (31), as a woven fabric or as a nonwoven fabric.

6. Layer composite according to one of claims 1 to 5, wherein at least a part of the polymer layer (30) projects out of the layer composite.

7. Layered composite according to one of claims 1 to 6, wherein the polymer layer (30) is not post-crosslinkable or post-crosslinked.

8. Layer composite according to one of claims 1 to 7 having at least one of the following properties: The substrate (10) and top layer (40) are independent glass layers with a thickness of > 1 mm to < 40 mm; the polymer layer (30) has a thickness of > 0.05 mm to < 4 mm; the sum of the thicknesses of the polymer layer (30) and adhesive layers (20, 21) is > 0.06 mm to < 5.3 mm and the thickness of an adhesive layer (20, 21) is > 1 pm to < 650 pm.

9. Method for producing a layered composite according to any one of claims 1 to 8, comprising: A) Providing an arrangement comprising a substrate (100) and a cover layer (200), wherein the substrate (100) comprises a first substrate side (110) with a vertically viewed upper substrate edge (120), a vertically viewed lower substrate edge (130), a first substrate side edge (140) and a second substrate side edge (150) opposite the first substrate side edge; the cover layer (200) comprises a first cover layer side (210) with a vertically viewed upper cover layer edge (220), a vertically viewed lower cover layer edge (230), a first cover layer side edge (240) and a second cover layer side edge (250) opposite the first cover layer side edge; the first substrate side (110) and the first cover layer side (210) are oriented towards each other at an angle a in the arrangement and an angle bisector (1000) of the angle a is formed;the upper substrate edge (120) and the upper top layer edge (220) are opposite each other in the arrangement; the lower substrate edge (130) and the lower top layer edge (230) are opposite each other in the arrangement; the first substrate side edge (140) and the first top layer side edge (240) are opposite each other in the arrangement; the second substrate side edge (150) and the second top layer side edge (250) are opposite each other in the arrangement; in the arrangement, the distance of the upper substrate edge (120) to the upper top layer edge (220) is greater than the distance of the lower substrate edge (130) to the lower top layer edge (230); in the arrangement between the lower substrate edge (130) and the lower cover layer edge (230) a first seal (500) is provided which prevents the escape of fluids between the lower substrate edge (130) and the lower cover layer edge (230); in the arrangement between the first substrate side edge (140) and the first cover layer side edge (240) a second seal (510) is provided which prevents the escape of fluids between the first substrate side edge (140) and the first cover layer side edge (240); in the arrangement between the second substrate side edge (150) and the second cover layer side edge (250) a third seal (520) is provided which prevents the escape of fluids between the second substrate side edge (150) and the second cover layer side edge (250);so that the arrangement forms a container open on one side for receiving fluids and in this container is also an adhesive (310) capable of curing; B) Pivoting the substrate (100) and the top layer (200) towards each other, so that the distance between the upper substrate edge (120) and the upper top layer edge (220) decreases and the adhesive (310) is moved in the direction of the upper substrate edge (120) and the upper top layer edge (220); C) Curing of the adhesive (310); characterized in that in the arrangement according to A) a polymer layer (400) with a tensile strength according to DIN EN ISO 527 of > 30 MPa is also present between the substrate (100) and the top layer (200).

10. A method according to claim 9, wherein at least during steps A), B) and C) the temperature of the polymer layer (400) is < 50 °C.

11. A method according to claim 9 or 10, wherein after step C) the layer composite is not heated to a temperature of > 100 °C.

12. Method according to one of claims 9 to 11, wherein at least at the beginning of the swiveling in step B) the adhesive (310) has a viscosity at 20 °C according to DIN EN 12092 of < 50000 mPas.

13. Method according to any one of claims 9 to 12, wherein the polymer layer (400) comprises a polyester polymer, a thermoplastic polyurethane polymer or a polycarbonate polymer.

14. Method according to any one of claims 9 to 13, wherein the polymer layer (400) is formed as a film without cutouts, as a film with one or more cutouts (31), as a woven fabric or as a nonwoven fabric.

15. Method according to any one of claims 9 to 14, wherein the polymer layer (400) is not post-crosslinkable or post-crosslinked.

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