Composition for the production of a barrier layer, barrier layer, use of a composition, coated substrate and method for applying a barrier layer

Abstract

Composition for the production of a barrier layer, comprising a polymer component, surface-modified inorganic particles in the form of metal particles, which are corrosion-passivated nanoscale platelet-shaped aluminum particles, and a proportion of an organic solvent. wherein the particles are modified on their surface with one or more double bond functionally reactive silane components and with one or more amino functional components, wherein the amino functional component(s) is / are selected from a multifunctional low molecular weight aliphatic, aromatic, heterocyclic component, amino functional polyether components and mixtures thereof; wherein the particles have a nanoscale platelet thickness; and wherein the polymer component is selected from polyacrylates, polyvinylidene chlorides, polyurethanes, polyesters and cellulose derivatives.

Description

[0001] The invention relates to a composition for the production of barrier layers, the use of the compositions according to the invention for the production of barrier layers, barrier layers produced from the compositions according to the invention, substrates provided with a barrier layer, and a method for applying a barrier layer to a substrate.

[0002] Packaging and containers made from a wide variety of materials are of general importance, both for private and industrial use. In the simplest case, these packages and containers merely serve as receptacles.

[0003] Especially when storing valuable, sensitive, or hazardous goods, these must be protected from environmental influences or external factors in general. This can be achieved, in particular, through additional protective or barrier layers applied to the respective containers and packaging. Additional protection for valuable and sensitive goods, which often cannot be provided solely by conventional packaging materials, primarily concerns protection against environmental influences such as moisture, oxygen, light, and temperature.

[0004] Packaging and containers with such additionally applied barrier layers are widely used, especially for materials in the pharmaceutical, food and beverage, chemical, computer and construction industries.

[0005] As a result of the aspects described, there is an urgent and growing need in industrial societies for cost-effective and easy-to-apply barrier coatings for containers and packaging that exhibit good adhesion to common packaging materials and whose elastic properties and hardness are adjustable.

[0006] However, there is an increasing need for new, innovative barrier coatings not only for application on containers and packaging or films, but also for the protection of metals against corrosion, where the barrier properties of the coating or applied conversion layers against oxygen, electrolytes and water are of fundamental importance.

[0007] Metal layers deposited using vacuum processes, for example using the so-called Physical Vapor Deposition (PVD), especially PVD aluminum layers, have proven effective as barrier layers, but these often themselves need to be protected by applying organic coatings to protect against oxidation and corrosion.

[0008] The use of PVD-coated films as packaging and for protecting sensitive goods from oxygen and water vapor is well-established. The barrier effect of a vapor-deposited thin metallic layer is very high.

[0009] However, the complex and expensive production processes in high vacuum and the sometimes high susceptibility of these coatings to corrosion are disadvantages. Therefore, alternative barrier coatings have already been recommended in the prior art for a number of applications.

[0010] CN 2015 76687 U describes fluorine-free films consisting of a base layer, an aluminum metal intermediate layer and a protective layer with a high barrier effect against water vapor and other environmental factors, for increasing the weather resistance of photovoltaic cells.

[0011] Coated aluminum foils are also described in JP 2001-6631A as excellent gas and electrolyte barrier layers.

[0012] US 4 601 943 A also describes aluminum foils which, when placed between two plastic films, have vapor barrier properties and can thus be used as fire protection.

[0013] DE 101 52 266 C1 describes coated water-soluble hollow bodies using water-soluble polymers with a coating of graphite, titanium and chromium nitride and carbonitride applied in the gas phase by means of Chemical Vapor Deposition (CVD).

[0014] WO 2008 / 034733 A1 (EP 2 069 210 B1) describes packaging containers with barrier layers made of single- or multi-layer arrangements incorporating metal foils and metal sheets, for example, made of aluminum, which are optionally combined with different layers of plastics, also in the form of composite films, wherein the metal layers are preferably applied to the containers using PVD processes. This multi-layer arrangement can alternatively also be obtained by so-called multi-component injection molding.

[0015] Barrier layers consisting of organic film formers such as polyvinylidene chloride (PVDC) or ethylene-vinyl alcohol copolymers (EVOH) are also used. However, the barrier effect of these polymer layers is not sufficiently high for most applications requiring an oxygen and, in particular, a water barrier. Therefore, these barrier layers are usually combined with other metallic or oxide barrier layers.

[0016] To improve the barrier effect, so-called hybrid materials have also been used. DE 196 50 286 A1 describes, as an example, inorganic-organic hybrid materials (ORMOCER layers), which are used particularly on a substrate already coated with SiO₂. xThese hybrid coatings exhibit barrier properties on pre-coated substrates. Experience has shown that these coatings are particularly well-suited for application on polar, hydroxyl-containing, and metallic surfaces, while they are less suitable for non-polar surfaces, e.g., polyolefinic surfaces, especially on flexible and / or elastic substrates (e.g.,

[0017] Films, especially packaging films), are not suitable for creating a permanent barrier effect due to their hardness, brittleness or lack of elasticity.

[0018] To achieve maximum effect with these hybrid material layers, a two-layer structure consisting of a metallic or oxide layer and a layer of the hybrid material is often necessary.

[0019] WO 01 / 66654 A1 and WO 01 / 66655 A1 describe mixtures of condensation products of bis-aminomethoxysilane or other aminosilanes and phenolic compounds in methanol for the production of barrier layers.

[0020] In WO 01 / 66656 A2 and WO 01 / 66662 A2, mixtures of bis-aminotrimethoxysilane and aminoethylaminopropyl-trimethoxysilane with multifunctional acrylates and ethylene unsaturated organic acids are described as UV-curing barrier layers.

[0021] DE 103 50 125 A1 describes organosilane-based barrier coatings for gases, comprising at least one organoalkoxysilane whose organofunctionality includes at least one unsaturated hydrocarbon group, at least one aminoalkylalkoxysilane, at least one polyol, and at least one co-condensate of the aforementioned components. These barrier coatings can be advantageously used on base-insensitive substrates such as polyolefins. However, experience has shown that, particularly with thinner polyester substrates or metal substrates, certain substrate damage can occur due to the water content and, above all, the relatively high content of amino-functional silanes in the coating composition.This is especially true for surface-modified, thin platelet-shaped metal particles due to the basic corrosive properties of this matrix material when such particles are used in such coating compositions.

[0022] However, the most important properties of barrier coatings, besides their blocking effect against the respective environmental influences, are primarily their robustness, flexibility and cost in the application process, as well as the permanence of these coatings.

[0023] The immense quantities of packaging and containers produced in industrialized nations, as well as the prevailing global pressure to reduce costs and increase productivity, play a significant role in the requirements for a barrier layer.

[0024] As already explained, according to the current state of the art, metal layers, mostly aluminum metal layers, are applied as barrier layers to a wide variety of materials in a vacuum using PVD processes. These processes are both energy- and cost-intensive and, due to the use of a vacuum process, also not very flexible.

[0025] The aspects mentioned at the beginning, namely universal applicability and adhesion to different substrates, cost-effective and easy application, control of hardness and elastic properties, can best be addressed by an organic coating.

[0026] However, it has been shown that even highly cross-linked two-component (2K) clearcoats alone cannot provide a sufficient barrier against gases.

[0027] DE 10 2008 052 678 A1 discloses multilayer nanoparticles comprising cores made of an inorganic material, at least one intermediate layer comprising silane groups and at least one outer layer comprising polyoxyalkylene monoamines.

[0028] DE 10 2013 113 885 A1 discloses coated metal pigments, their production and their use.

[0029] US 2015 / 0159036 A1 discloses stable primer formulations comprising surface-modified metal oxide nanoparticles.

[0030] DE 10 2015 120 557 A1 discloses pigment particles with a surface coating and coating composition with such pigment particles.

[0031] Therefore, there is a need for barrier layers that are easier and more cost-effective to apply, while still providing a barrier effect, for example against oxygen and water vapor, on a similar scale to that achievable with the barrier effect of a PVD layer made of metal.

[0032] The object of the present invention is to propose a composition with which barrier layers or barrier coatings can be produced more cost-effectively, even in large quantities.

[0033] This problem is solved by compositions with the features of claim 1.

[0034] The composition according to the invention for a barrier layer can be applied in a particularly cost-, time-, and energy-efficient manner, especially using conventional and generally accessible painting systems, by dipping or by printing, in contrast to the PVD processes described in the prior art.

[0035] This also applies to substrates in the form of films, where the compositions according to the invention can be applied as a layer, in particular by means of squeegees or a printer.

[0036] Furthermore, the present invention avoids production-related disadvantages of barrier coatings consisting of PVD metal layers. According to the present invention, the time-consuming, energy-intensive, and ultimately costly metal coating process of the established prior art is replaced by the application of a liquid composition of coating components.

[0037] According to the invention, the composition comprises a polymer component, surface-modified inorganic particles in the form of metal particles, which are nanoscale platelet-shaped aluminum particles passivated against corrosion, and a portion of an organic solvent, which optionally comprises a reactive diluent. The particles are modified on their surface with one or more double-bond functionally reactive silane components and with one or more amino-functional components, wherein the particles have a nanoscale platelet thickness. The polymer component is selected from polyacrylates, polyvinylidene chlorides, polyurethanes, polyesters, and cellulose derivatives.

[0038] For the purposes of the present invention, the term "particles with nanoscale platelet thickness" refers in particular to platelet-shaped particles with an average thickness of approximately 200 nm or less, in particular approximately 100 nm or less, more preferably approximately 80 nm or less and optionally approximately 60 nm or less.

[0039] The average thickness of the plate-shaped particles can be determined manually using electron microscopy images.

[0040] The barrier coatings according to the invention, containing plate-shaped aluminium particles, are not only suitable as barrier coatings for protection against gases and moisture, but also offer protection against heat radiation and UV light in particular.

[0041] In the case of cellulose derivatives, partially esterified cellulose derivatives are particularly preferred, wherein the degree of esterification is preferably approximately 1 to approximately 5 mol%, for example approximately 2 mol%.

[0042] The amino-functional component for surface modification of the platelet-shaped particles is selected in particular from multi-functional low-molecular-weight aliphatic, aromatic and heterocyclic components as well as amino-functional polyether components or mixtures thereof.

[0043] The double bond functionally reactive silane component for surface modification of the platelet-shaped particles is preferably selected from the components vinyltrimethoxysilane and 3-methacryloxypropyltrimethoxysilane or mixtures thereof.

[0044] The multifunctional low molecular weight aliphatic, aromatic or heterocyclic components typically have a molecular weight of approximately 600 g / mol or less, in particular approximately 500 g / mol or less.

[0045] Typically, the molecular weight is approximately 40 g / mol or more, although components with lower molecular weights can also be used according to the invention.

[0046] The concentration of these surface-modified platelet-shaped particles according to the invention in the barrier coating is particularly approximately 0.1 to approximately 60 wt.%, preferably approximately 1 to approximately 40 wt.%, and more preferably approximately 1 to approximately 30 wt.%, based on the solids content (SF) of the polymer component used as a binder. This applies especially when the oxygen barrier property of the barrier coating to be produced is of primary importance.

[0047] High concentrations of platelet-shaped aluminum particles, however, lead to a noticeable decrease in the transparency of the coatings, which is undesirable in a number of applications. Even in compositions designed purely for UV curing, high proportions of aluminum particles are not conducive to curing the barrier coating or its polymer component across the entire thickness of the coating and achieving uniform properties.

[0048] Here, the use of mixtures of platelet-shaped particles is recommended, which, in addition to aluminum particles, also include other particles, in particular silicate particles. In such cases, the aluminum particle content is preferably limited to approximately 10 wt% or less.

[0049] If the transparency of the coating is of secondary importance, higher aluminum particle contents can also be used, in which case either additionally or exclusively, the polymer component is thermally hardened and adjusted accordingly.

[0050] If a barrier effect against the permeation of water and water vapor is particularly desired, the composition according to the invention preferably comprises approximately 30 wt.% to approximately 60 wt.%, more preferably approximately 50 wt.% to approximately 58 wt.% of surface-modified nanoscale particles, in particular aluminum particles, based on the solid fraction of the polymer component.

[0051] In both cases, the surface-modified platelet-shaped particles according to the invention preferably have a mean platelet thickness of approximately 10 to approximately 200 nm, in particular of approximately 20 to approximately 100 nm and especially preferably approximately 20 to approximately 80 nm.

[0052] It is evident that in the solvent- and reactive diluent-based barrier coatings according to the invention, the strong cross-linking, which is important for the barrier property, can be formed primarily through chemical bonds. As shown in the following Examples 1 to 3, particles that exhibit an olefinic double bond due to their surface modification can obviously strongly promote cross-linking in the solvent- and reactive diluent-based barrier layers according to the invention and thus significantly enhance the barrier properties.

[0053] The solvent- and reactive diluent-based compositions for barrier layers according to the invention therefore preferably include surface-modified inorganic nanoscale platelet-shaped particles with olefinically double-bond-functional silanes and, in particular, surface-modified nanoscale platelet-shaped metal particles, wherein the double-bond-functional reactive silane component for surface modification of the platelet-shaped particles is again preferably selected from the components vinyltrimethoxysilane and 3-methacryloxypropyltrimethoxysilane or mixtures thereof.

[0054] For the solvent- and / or reactive diluent-containing compositions according to the invention, which contain rather nonpolar, hydrophobic polymer components, such as modified and esterified celluloses, polyurethanes, polyacrylates, polyvinyl acetates, and polyesters, it has been found that surface-modified platelet-shaped particles are particularly suitable, having surface modifications with high proportions of double-bond functional silanes. These components are deposited on the surface of a platelet-shaped particle, in particular a platelet-shaped metal particle, and more preferably an aluminum particle, and are preferably first chemically crosslinked by reheating.

[0055] The addition of a radical initiator can optionally lead to further radical crosslinking of the olefinic double-bond functional silane components, resulting in the metal platelets being encased in a densely crosslinked hybrid layer of silane and organic components. This layer surrounding the metal platelets inhibits water absorption at the platelet surface and protects the metal platelets from corrosion and, in particular, oxidation.

[0056] For radical compositions, especially those containing UV-curing agents and reactive diluents, it may still be advantageous to perform only thermal curing of the particle surface modification in order to subsequently enable radical crosslinking of the double bond function of the barrier particles into the UV-curing polymer network.

[0057] The solvent- and reactive diluent-containing compositions according to the invention comprise surface-modified platelet-shaped metal particles and / or platelet-shaped oxide inorganic particles with olefinically double-bond-functional silanes.

[0058] The barrier layers ultimately obtained from the compositions according to the invention preferably have a dry film thickness of approximately 0.1 µm to approximately 20 µm, in particular of approximately 0.5 µm to approximately 10 µm and more preferably of approximately 0.5 µm to approximately 5 µm and in particular have a layer with amino- and double-bond functionally surface-modified platelet-shaped particles, embedded in a preferably thermosetting polymer matrix.

[0059] In the context of the present invention, dry film thickness refers to the thickness of a coating according to the invention after curing, measured according to DIN EN ISO 139 (at a temperature of 23°C and a relative humidity of 50%) using the eddy current method according to DIN EN ISO 2808:2004; by fixing the substrate with and without the surface-applied barrier coating to a suitable metal substrate. The difference between the obtained values ​​then represents the dry film thickness of the barrier coating.

[0060] In a further embodiment, a barrier layer according to the invention can be overcoated with one or more optionally thicker, particle-free, and optionally also thermosetting coatings. This embodiment of a barrier coating is particularly suitable for preventing water permeation, wherein the barrier coating for this purpose is preferably provided with a surface coating with a layer thickness of approximately 4 µm to approximately 60 µm, in particular approximately 10 µm to approximately 40 µm, and more preferably approximately 15 µm to approximately 25 µm, a clear coat, in particular particle-free, wherein the underlying layer according to the invention (barrier layer) comprises a layer area containing nanoscale platelet-shaped aluminum particles, preferably approximately 0.5 µm to approximately 3 µm thick, and in particular approximately 0.7 µm to approximately 1 µm thick.

[0061] The lower layer (barrier layer according to the invention) for preventing water permeation preferably contains approximately 30 wt.% to approximately 60 wt.%, more preferably approximately 50 wt.% to approximately 58 wt.% of the surface-modified nanoscale thick platelet-shaped particles according to the invention, based on the solid fraction of the binder.

[0062] Furthermore, the barrier coating according to the invention is preferably formulated in a color-neutral, dark, or white manner and exhibits no metallic effects. This can be achieved by the additional use of white or black pigments, whereby the barrier coating can then be formulated to be largely color-neutral, dark, or white and preferably exhibits no visually noticeable metallic effects.

[0063] In principle, the barrier coating according to the invention can be used on different substrates, with application to plastic materials for packaging and containers being preferred.

[0064] The composition according to the invention can be used to produce barrier layers on substrates of all kinds. In particular, it is used to produce barrier coatings on metal, paper, cardboard and plastic substrates of all kinds and combinations thereof, especially for producing barrier coatings on plastic packaging and molded parts of all kinds, and further preferably on plastic cartridges and plastic capsules, plastic films and plastic bottles, consisting of polyamide (PA), polyethylenes (HDPE, LDPE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), polyacrylates (especially polymethyl methacrylate PMMA), polyesters (especially polyethylene terephthalate PET), polylactides (PLA) and polycarbonate (PC).

[0065] However, it can also be used for the corrosion protection of metal substrates such as aluminum alloys, steels or other ferrous materials.

[0066] Optionally, the barrier layer according to the invention is overcoated with a thicker, relatively highly cross-linked thermosetting organic, metal particle-free coating or is part of a multi-layer coating, which is used, for example, in industrial and automotive coatings.

[0067] It can also be applied as part of a multi-layer application and / or a multiple coating on other metal and plastic surfaces, and is further preferably applied to two opposite sides of a substrate, such as the inside and outside of molded bodies or films.

[0068] The use according to the invention further includes applications in which at least one barrier layer of a multilayer structure with several different layers and / or a multilayer structure with several identical layers is produced from the composition, preferably on metal or plastic surfaces and more preferably on two opposite sides, for example on the inside and outside of molded bodies or films.

[0069] The invention further relates to a substrate coated with a barrier layer, in particular in the form of a shaped body, a hollow body, a planar substrate or a film with a barrier layer applied inside and / or outside.

[0070] Finally, the invention relates to a method for applying a barrier layer to a substrate, the method comprising the steps of: - Providing a composition according to the invention as described above; and - Application of the composition to the substrate surface by means of squeegees or printing processes; wherein the substrate is preferably a film, in particular a packaging film.

[0071] These and other advantages of the invention will be described in more detail below with reference to the examples and figures. Fig. Figure 1 shows the weight increases of test specimens P2 (without clear coat KL) and P3 (+ 20 µm KL) coated differently with the barrier coating compared to the uncoated reference sample P1; Fig. Figure 2 shows the weight increases for the uncoated specimen and the specimens P4, P5 and P6, which were coated with barrier layers of 2.5 µm thickness and with a clear coat layer (CL) of varying thickness; Fig.Figure 3 shows the weight increases of the uncoated reference sample P1 and the test specimen P8 coated only with clear lacquer (KL) compared to the test specimen P7 with a 0.8 µm thin barrier layer according to the invention and a clear lacquer layer (KL) applied thereto; Fig. Figure 4 shows a comparison of the weight increases in the uncoated reference sample P1 and in the test specimens P9, P10 and P11 coated with barrier layers according to the invention, wherein the barrier layers are 2.5 µm thick and contain differently surface-modified aluminium particles; Fig. Figure 5 shows the transmission spectrum of aqueous bromophenol red solutions as a function of pH; Fig.Figure 6 shows a comparison of the oxygen barrier effect (in the form of OTR values ​​based on a layer thickness of 10 µm) of LDPE films coated with UV barrier reference coatings (R4 - without particles, P17 - unmodified particles) and with UV barrier coatings according to the invention, wherein the UV barrier coatings according to the invention contain 1.2 wt.% aluminum particles with a mean platelet thickness of 50 µm and additionally isocyanates as a hardener component (P18, P19; reference P20); and Fig.Figure 7 shows a comparison of the oxygen barrier effect (in the form of OTR values ​​based on a layer thickness of 10 µm) of a UV barrier reference coating (R4 - without particles) and the LDPE films coated with UV barrier layers according to the invention (here without the addition of isocyanate hardener) with a metal particle content of 0.3 wt.% (P21) and partially additionally with a content of 0.8 wt.% (P22) or 1.6 wt.% (P23) of non-metallic nanoscale thick silicate particles (talc, platelet thickness approx. 80 nm). Example 1: Implementation of the surface modifications of aluminium particles according to the invention for use in solvent- and reactive diluent-containing compositions

[0072] A polyetheramine (Jeffamine® D400 from Huntsman Corp.) is dissolved in 225 g of butyl acetate (BuAc), resulting in a solid polyetheramine content of 4.0 wt% by mass. While stirring at 800 rpm on a dissolver (Getzmann), 60 g of a solvent-containing paste containing approximately 10 wt% nanoscale platelet-shaped aluminum particles (Decomet 1008 / 10 from Schlenk Metallic Pigments GmbH) are added within 5 minutes, creating a particle dispersion with an average thickness of approximately 2.5 wt%. The particles have a mean thickness of approximately 50 nm.

[0073] The particle dispersion is then homogenized for 20 minutes at room temperature while maintaining the stirring speed. Vinyltrimethoxysilane (VTMO) is slowly added dropwise until a VTMO content of 8.0 wt% is reached. Likewise, another reactive olefinic double-bond functional silane component A is added dropwise until a content of Y wt% is reached, and optionally another reactive epoxide functional silane component B (reference) is added until its content reaches Z wt%. The mixture is then stirred for 5 minutes and finally heated to 70 °C. The wt% values ​​given above are based on the mass of the particles (solids FK) in the dispersion.

[0074] After reaching a temperature of 70 °C, azo-bis-isobutylonitrile (AIBN) dissolved in butyl acetate (5 wt% solution) is slowly added dropwise until a proportion of 1.6 wt% AIBN, based on the weight fraction of the particle(s), is reached. To crosslink the VTMO and the reactive silane component A, and optionally the silane component B, the temperature is maintained at 70 °C for 30 minutes with stirring.

[0075] The particle dispersion is cooled to room temperature while stirring, centrifuged, and then the particle content is adjusted back to approximately 10 wt% by adding butyl acetate. The composition is then in the form of a paste.

[0076] The nanoscale platelet-shaped aluminum particle pastes obtained through the described particle modification process are subsequently used for the barrier coatings according to the invention.

[0077] Table 1 below lists the compositions of the surface modifications M1, M2 (according to the invention), M3 (reference) for the differently surface-modified particles used in the barrier coatings. Table 1 Formulations M1, M2 (according to the invention), M3 (reference) for the surface modification of particles Modification component M1 M2 M3 (reference) Jeffamine D400 [wt% / particles] 4,0 4,0 4,0 Vinyltrimethoxysilane VTMO [wt% / particle weight] 8,0 8,0 8,0 Azo-bis-isobutylonitrile AIBN [wt% / particle weight] 1,6 1,6 1,6 Olefin-functional silane component A: MEMO(3-Methacryloxypropyltrimethoxysilane),[Y wt% / FK particles] 0,0 8,0 0,0 Epoxy-functional silane component B: GLYMO(3-Glycidyloxypropyltrimethoxysilane)[Z wt.% / FK particles] 0,0 0,0 8,0 Example 2: Barrier effect of the barrier coating according to the invention against the absorption of water

[0078] To achieve a high barrier effect when samples are exposed to aqueous media, it has proven advantageous to use barrier coatings with the highest possible content of metal barrier particles. The sole use of oxide barrier particles is less desirable in this case due to their increased water retention capacity. However, the addition of oxide particles to metal particles in smaller quantities can be beneficial, as they impair the coating's transparency less and are more cost-effective. For example, the addition of silicate particles (e.g., talc particles) often allows for a corresponding reduction in the amount of more expensive aluminum particles without significantly altering the coating's barrier properties.

[0079] The compositions for producing the barrier layers according to the invention were formulated with a content of 55 wt.% barrier particles made of aluminum and a solvent-based binder system.

[0080] Polyethylene test specimens (sealable cartridges, see below) were coated three times by dip coating using a composition according to the invention with the particle sample with modification M1 from Example 1, Table 1. After three dip coatings, the resulting coatings had a total layer thickness of approximately 2.5 µm. The composition according to the invention for producing the barrier layer was composed as specified in Table 2: Table 2 Composition for the production of the barrier layer according to the invention, with approximately 20 vol.% or approximately 55 wt.% nanoscale and platelet-shaped aluminum particles. Components Inventive composition [g] Binder component CAB 381 - (20 wt% butyl acetate) 1,50 Butyl acetate 46,00 Methoxypropyl acetate 46,80 Aluminium particle component M1 (10 wt% butyl acetate) 5,00 Metatin 812 ES (DBTL) 0,10 Hardener component Desmodur N 3600 0,60

[0081] The binder component CAB 381 is a cellulose acetate butyrate (manufacturer: Eastman).

[0082] Dibutyltin (metatin 812 ES, manufacturer: DOW Chemicals) is used as a catalyst for the hardening reaction.

[0083] Desmodur N 3600, an aliphatic polyisocyanate (manufacturer Covestro), is used as a hardening component in the formulation.

[0084] A commercially available two-component (2K) clear coat (2K-HS clear coat CC4; MIPA) was additionally applied to some of the test specimens by spraying to achieve a dry film thickness of 20 to 30 µm.

[0085] A solvent-based formulation was used for both coatings. The coated specimens were subsequently cured in a convection oven at 70 °C for 30 minutes and conditioned for at least 48 hours in a climate chamber (at 23 °C, 60% relative humidity). Sealable polyethylene cartridges approximately 32 cm long, 5 cm in diameter, and weighing approximately 46 g were used as test specimens to characterize water and water vapor permeability.

[0086] The water absorption by the barrier coating was characterized by a water immersion test in which the specimens, each filled with 65 g of phosphorus pentoxide, were immersed in water at 30 °C for a total of 600 h. The water absorption of the specimens with and without the barrier coating, as well as of the specimens with a barrier coating and an optional additional clear coat layer, was monitored and evaluated gravimetrically over time.

[0087] In Fig. Figure 1 shows the mass increases obtained in the water immersion test as a function of time for the uncoated reference sample P1 compared to the differently coated samples P2 and P3.

[0088] For samples P2 and P3, a composition according to Table 2 was used for dip coating. Sample P3 was additionally coated with a clear coat (CL), resulting in a dry film thickness of approximately 20 µm.

[0089] It can be seen that the uncoated reference sample P1 shows a relatively strong water absorption, while the test specimen (P3) coated with the barrier layer according to the invention and the clear varnish shows no measurable water absorption.

[0090] For test specimen P2, coated only with the barrier layer according to the invention, a moderate level of water absorption was observed in the water immersion test compared to both extremes. Furthermore, in contrast to test specimen P3, which was additionally coated with clear lacquer, some signs of delamination were observed in test specimen P2, coated only with the barrier layer, but only after approximately 600 hours.

[0091] From the in Fig. The results shown in Figure 2 indicate that a clear coat layer of approximately 20 µm dry film thickness applied over the barrier layer according to the invention is advantageous for achieving a good barrier effect against water for a variety of applications, whereas with a significantly greater thickness of the clear coat layer, the barrier effect against water may even deteriorate.

[0092] In order to enable the clearest and most meaningful differentiation between the samples, the tests in the two-layer structure (barrier layer and clear coat layer) were still carried out with a clear coat layer thickness of 40 µm.

[0093] Out of Fig. 3 shows that even a very thin barrier layer according to the invention with a layer thickness of approximately 0.8 µm (test specimen P7) has an extremely advantageous effect with regard to the water barrier property compared to a single 40 µm thick clear coat layer (test specimen P8).

[0094] In summary, it can be stated that by using a barrier layer made from a composition according to the invention and an additional clear coat layer, a strong barrier effect against water absorption can be achieved for an extended period, even when the test specimens are immersed in water. Furthermore, the coating of the test specimen, which was additionally top-coated with clear lacquer, showed excellent resistance to water and excellent wet adhesion. Example 3: Barrier effect of the barrier layer according to the invention against vapors and gases

[0095] In Table 3 below, the composition according to the invention, which uses modified aluminum particles, is listed as formulation 1. Reference formulation 1 represents barrier layer formulation 1 with non-surface-modified aluminum particles M0, which, apart from the significantly thinner dry film thickness (effect coating with a basecoat thickness according to the prior art of approximately 15 µm - 20 µm), corresponds to conventional effect pigment coatings. Reference formulation 2 represents the prior art known from DE 103 50 125 A1, WO 01 / 66654 A1, and WO 01 / 66655 A1. This formulation is characterized by the addition of different silane components to the organic binder and by the formation of so-called hybrid layers. Table 3 Inventive composition with modified aluminium particles (formulation 1), reference formulation 1 which corresponds to effect pigment lacquers, and reference formulation 2 according to the prior art Components Inventive formulation 1[g] Reference formulation 1[g] Reference formulation 2 [g] Binder component CAB 381 (20 wt% butyl acetate) 1,50 1,50 1,50 Butyl acetate 46,00 46,00 46,00 MPA 45,40 45,40 45,40 Aluminum particle modification M0, each as a 10 wt.% paste 0,00 5,00 5,00 M1, M2, M3 each as a 10% by weight paste 5,00 0,00 0,00 Metatin 812 ES (DBTL) 0,10 0,10 0,10 VTMO 0,00 0,00 0,02 Hardener component Desmodur N 3600 0,60 0,60 0,60 MPA 1,40 1,40 1,40

[0096] To achieve a high barrier effect when samples are exposed to aqueous media, it has proven advantageous to use barrier layers with a high content of metal barrier particles. Oxide barrier particles are less suitable in this case due to their increased water retention capacity.

[0097] The barrier layers obtained from these solvent-based compositions (binder systems) each have a content of approximately 55 wt% of aluminum barrier particles. 3.1. Barrier effect of the barrier layer according to the invention against water vapor

[0098] The barrier effect of the barrier layer according to the invention against gases such as water vapor was investigated by subjecting the test specimens (polyethylene cartridges) filled with 65 g of phosphorus pentoxide to a condensation water test in accordance with DIN EN ISO 6270 and determining the weight increase of the cartridges due to water absorption.

[0099] The graphic in Fig. Figure 4 shows a comparison of the weight gains of the uncoated specimen P1 and the specimens P9, P10 and P11, which were coated with a 2.5 µm thick barrier layer according to the invention, which contained different surface-modified aluminum pigments, when the specimens were subjected to condensation water testing in accordance with DIN EN ISO 6270 as a function of the duration of the load.

[0100] The results in Fig.Figure 4 shows that the formulations of the barrier layers according to the invention, which contain the aluminium particles, which were modified using an amino-functional low molecular weight polyether (Jeffamin) and exclusively with a double bond-functional silane component VTMO (test specimen P9; modification M1) or additionally with MEMO (test specimen P10; modification M2), exhibit a significantly increased water vapor barrier compared to the uncoated test specimens (P1).

[0101] The test specimens, which were modified using both an amino-functional low molecular weight polyether (Jeffamin) and with the double bond-functional silane component VTMO as well as with GLYMO (test specimen P11; modification M3 reference), showed a slightly lower barrier effect against water vapor, especially during longer exposure times. 3.2 Barrier effect of the barrier layer according to the invention against carbon dioxide gas CO2

[0102] The barrier effect against gases such as carbon dioxide was determined in a practical manner by first producing a hydrogen carbonate / carbonic acid buffer based on a natural, carbonated mineral water (Eltina Sprudel, Eberstädter Mineralbrunnen).

[0103] To achieve a high barrier effect when samples are exposed to aqueous media, it has proven advantageous to use barrier layers with a high content of metal barrier particles. Oxide barrier particles are less suitable in this case due to their increased water retention capacity. These barrier layers contain approximately 5 wt% aluminum barrier particles.

[0104] To prepare the bicarbonate / carbonic acid buffer, 765 mg of sodium bicarbonate were first dissolved in 1.5 liters of distilled water and subsequently adjusted to a pH of 6.1 by adding a highly dilute hydrochloric acid. 6 mg of bromophenol red pH indicator (CAS: 102185-50-2) were then added to this solution as an indicator.

[0105] To test the CO2 barrier properties, 250 g of this buffer solution were filled into uniform, approximately 15 cm long, sealable test specimens made of polyethylene terephthalate PET (weight approximately 5 g) with a wall thickness of approximately 80 µm and a diameter of approximately 4 cm and sealed gas-tight with a corresponding lid made of the same material.

[0106] During a 288 h (24 day) shaking test with 2 strokes per sec, a constant diffusion of the gaseous carbon dioxide present through the wall of the test specimens takes place, which results in a pH change of the aqueous indicator solution inside the vessels and can be tracked and quantified colorimetrically using a UV-Vis spectrometer.

[0107] The Fig. Figure 5 shows that a transmission difference ΔT between 577 nm and 660 nm correlates with the different pH values ​​and, in the case of the carbonate / carbonic acid buffer system, with the carbon dioxide content in the gas-tight sealed specimens.

[0108] If the transmission differences are determined analogously for the differently coated test specimens after a 288 h vibration load, very different values ​​are obtained, as shown in Table 4. Table 4 Transmission differences ΔT of the differently coated PET test specimens after a 288 h shaking load Sample name ΔT value PET test specimens without coating (P0) 18.5 PET test specimens with reference formulation 1 (P12) 15.9 PET test specimens with reference formulation 2 (P13) 16.8 PET test specimen + formulation with aluminum particles M1 (P14) 14.1 PET test specimen + formulation with aluminum particles M2 (P15) 14.4 PET test specimen + formulation with aluminum particles M3 (reference P16) 15.2

[0109] Looking at the results in Table 4, the following ranking according to increasing CO2 barrier can now be determined for the solvent-based barrier layer compositions (Table 3), containing the differently modified aluminium particles M1, M2, M3 (Table 1): Reference 0 (P0) < Reference 2 (P13) < Reference 1 (P12) < with aluminum particles M3 (Reference P16) < with aluminum particles M2 (P15) ≅ with aluminum particles M1 (P14)

[0110] From the ranking of the different solvent-based barrier layers above, it is now clearly evident that the formulations containing the aluminum particles modified using an amino-functional low molecular weight polyether (Jeffamin) and a double-bond-functional silane component VTMO and / or MEMO show a significantly increased CO2 gas barrier compared to the corresponding reference formulations, which contain the unmodified aluminum particles (P12; reference formulation 1) and / or which additionally contain the corresponding double-bond-functional silane component VTMO (at the appropriate concentration) as a direct addition to the formulation (P13; reference formulation 2).

[0111] The test specimens, which were modified using an amino-functional low-molecular-weight polyether (Jeffamin) and with the double-bond-functional silane component VTMO as well as with GLYMO (reference P16; modification M3), showed a slightly weaker barrier effect against CO2 compared to the barrier coatings with the modified aluminum particles with M1 or M2 (P14 and P15, respectively). The uncoated test specimen (P0) exhibited the weakest gas barrier effect. 3.3 Barrier effect of a UV-curing coating containing reactive diluent according to the invention against oxygen

[0112] To achieve a high barrier effect in formulations containing reactive diluents according to the invention, it has proven advantageous to use metal barrier particles. However, a disadvantage is that while the metal particles increase the barrier effect against gases such as oxygen, they simultaneously significantly reduce the UV transparency of the composition necessary for UV curing of the coating. This leads to layers with a reduced degree of cross-linking, which in turn negatively affects the compactness of the layer and thus the barrier effect itself due to the lower density of the polymer network.

[0113] To compensate for this disadvantage, the following variants can be used, for example, according to the invention: Variant 1: A concentration of platelet-shaped metal particles of, for example, 1.2 wt% is chosen in the barrier layer formed from binder, hardener, reactive diluent, and initiator. This results in rather metallic and relatively opaque barrier layers. In order to achieve sufficient cross-linking of the barrier layer despite the low transparency, a thermal hardener component is additionally added to the composition according to the invention, e.g. in the form of isocyanates, which can compensate for the hindrance of cross-linking by the metal platelets reflecting UV light. Variant 2: A concentration of platelet-shaped metal particles of, for example, 0.4 wt% is selected in the barrier layer formed from binder, hardener, reactive diluent, and initiator. Despite the metallic particle content, this results in semi-transparent barrier layers, allowing UV curing to be carried out with a stronger cross-linking effect. This enables improved barrier properties to be achieved even without the use of additional hardener components. In this approach according to the invention, the barrier effect of the coating is further enhanced by the addition of more transparent, nanoscale-thick, platelet-shaped non-metallic particles, with an average platelet thickness preferably of approximately 10 nm to approximately 200 nm, particularly of approximately 20 nm to approximately 100 nm, and more preferably of approximately 20 nm to approximately 80 nm. Silicate and boron nitride particles are preferably used as non-metallic particles, and talc particles are even more preferably used.

[0114] For the solvent-free UV-curing barrier coatings, unmodified aluminum particles M0 and the non-pigmented UV-curing barrier coating were used as reference systems.

[0115] For the UV-curing barrier layers according to the invention, aluminium particles with the modification M1, M2 and M3 from Example 1 were added to the formulations (as described above in Variant 1).

[0116] Table 5 below lists the compositions of the UV-curing barrier layer formulations (according to variant 1) with a content of 1.2 wt.% aluminum particles and the additional use of isocyanates as a hardener component (Desmodur N 3390), and Table 6 lists the compositions according to the invention of the UV-curing barrier layer formulations without the addition of isocyanate hardener (according to variant 2), with a metal particle content of only 0.4 wt.% and partially with the additional addition of non-metallic nanoscale thick (platelet thickness approx. 80 nm) silicate (talc) particles Talc LP30 (LITHOS Industrial Minerals GmbH).

[0117] The aluminum particles (platelet thickness approx. 50 nm) modified according to the invention (M1, M2, M3) from Example 1 were used as metal platelets in the UV-curing barrier coatings P18, P19 and P20, and the non-surface-modified aluminum particles (M0) were used in the UV reference coating 3 (P17). The corresponding non-pigmented UV clear coat was also included in the investigation as a further reference system, UV reference coating 4 (R4).

[0118] In UV-curing formulations, the component Desmolux U 680H (Allnex, formerly Bayer) corresponds to the binder component, Desmodur N 3390 BA (Covestro, formerly Bayer) to the isocyanate hardener component, Laromer HDDA (BASF) to the reactive diluent hexanediol diacrylate, and Genocure ITX (Rahn) to the photoinitiator. Byk 306 is a frequently used additive, particularly for preventing surface defects in coating applications. For the production of the corresponding UV-curing barrier layer formulations, 10 g of each differently surface-modified aluminum particle was added as a 10 wt% paste, which corresponds to an approximately 1.2 wt% aluminum particle content based on the solids resulting from Desmolux, Desmodur, the photoinitiator or wetting additive, and the reactive diluent HDDA.This significantly reduced content of aluminum particles was chosen because otherwise the expected significantly reduced curing of the UV-curing systems would be expected. Table 5 Barrier layer formulations (according to variant 1) with aluminium particles modified according to the invention (P18 and P19), reference sample P20, reference formulation 3 (P17) which corresponds to effect lacquers, and reference formulation 4 according to the prior art for UV-curing clear lacquers (R4). R4 sample without particles P17 Sample with particles P18 Probe with particle M1 P19 Probe with particle M2 P20 Probe with particle M3 reference Desmolux U 680H (80% inHDDA) [g] 41,90 41,90 41,90 41,90 41,90 Desmodur N 3390 BA [g] 2,74 2,74 2,74 2,74 2,74 Laromer HDDA [g] 37,56 37,56 37,56 37,56 37,56 Irgacure 184, 50% in HDDA[g] 5,64 5,64 5,64 5,64 5,64 Genocure ITX [g] 2,00 2,00 2,00 2,00 2,00 Byk 306 [g] 0,16 0,16 0,16 0,16 0,16 10 wt.% aluminum particles Decomet 3008 / 10 - Paste M0 (untreated) [g] - 10,00 - - - 10% by weight aluminum particlesDecomet 3008 / 10;paste M1[g] - - 10,00 - - 10% by weight aluminum particlesDecomet 3008 / 10;paste M2[g] - - - 10,00 10% by weight aluminum particlesDecomet 3008 / 10;paste M3[g] - - - - 10,00 Table 6 Barrier layer formulations (according to variant 2) without the addition of isocyanate hardener, with an aluminum particle content of 0.4 wt.% and partially additional addition of non-metallic silicate (talc) particles (platelet thickness approx. 80 nm) with the aluminum particles (P22, P23), reference formulation 5 (P21), which corresponds to effect pigment lacquers, and reference formulation 4 according to the state of the art for UV-curing clear lacquers (R4). R4 probe without particles P21 sample with aluminum particles M2 P22 sample with aluminum particles M2 and TalcLP30 P23 sample with aluminum particles M2 and talc LP30 Desmolux U 680H (80% in HDDA) [g] 47,72 47,72 47,72 47,72 Laromer HDDA [g] 41,98 41,98 41,98 41,98 Irgacure 184, 50% inHDDA [g] 5,64 5,64 5,64 5,64 Genocure ITX [g] 2,00 2,00 2,00 2,00 Byk 306 [g] 0,16 0,16 0,16 0,16 10 Gew.-% Aluminium-Partikel Decomet3008 / 10 - Paste M2 [g] - 3,50 3,50 3,50 Talkum-Partikel LP30[g] - - 0,70 1,40

[0119] The UV-curable barrier layer formulations were applied to a 34 µm thick low density polyethylene LDPE film using a squeegee application to achieve a dry film thickness of approximately 10 µm.

[0120] The obtained OTR (Oxygen Transmission Rate) values ​​were then normalized to 10 µm by multiplying by the mean of the actual layer thickness and then dividing by 10 µm. The resulting OTR values ​​were expressed as OTR / 23 °C / 10 µm in ml / m³. 2 The OTR values ​​were measured in / day. OTR values ​​were measured according to the standard ISO 15105-1:2007-10.

[0121] In Fig. Figure 6 shows the oxygen permeability (OTR) values ​​obtained for the individual UV barrier coatings at 23°C. In comparison to the OTR values ​​obtained for the coated films, an OTR value of 3091 ml / m² was recorded for the uncoated LDPE film. 2 / day measured. The results further indicate that, assuming optimized surface modification of the barrier particles, in contrast to the barrier effect against water from Example 2, even relatively low addition amounts of the surface-modified barrier particles according to the invention result in very good barrier coatings against gases such as oxygen. Consequently, the following ranking of UV-curable barrier coatings can be given for the oxygen barrier effect (ordered from higher to lower barrier): P18 > P20 (reference) > P19 >> P17 (reference) >> Reference without particle R4

[0122] Out of Fig. It can therefore be deduced from section 6 that the UV-curable reference barrier layers on the LDPE films formulated without particles and the UV-curable reference barrier layers containing the unmodified aluminum particles exhibit the lowest oxygen barrier properties. In contrast, the LDPE films coated with the UV-curable barrier layers containing the aluminum particles modified according to the invention show very good oxygen barrier properties. The highest oxygen barrier was achieved with the UV-curable barrier layers containing the aluminum particles coated with the surface modification M1 according to the invention.

[0123] In Fig. Figure 7 shows the oxygen permeability (OTR) values ​​obtained at 23°C for the individual UV-curable barrier layers on LDPE films for the barrier layer formulations without the addition of isocyanate hardener, with a metal particle content of 0.4 wt%, compared to the oxygen permeability (OTR) values ​​obtained for the barrier layer formulations with the additional addition of non-metallic, nanoscale-thick (platelet thickness approx. 80 nm) silicate (talc) particles (P21, P22). As a further reference, the LDPE film coated with UV-curable varnish without metal particles was again included.

[0124] In comparison to the OTR values ​​obtained for the coated films in Fig.In the case of the barrier layer formulations with a content of 1.2 wt% aluminum particles (M2) and the additional use of isocyanate as a hardener component (P19), the isocyanate-free LDPE film (P21), containing only 0.4 wt% metal particles (M2), shows a significantly improved barrier effect. When 0.8 wt% nanoscale talc particles (Talc LP30) are added, resulting in a total particle content of 1.2 wt% each (the reference containing isocyanate and aluminum particles is P19 with 1.2 wt% aluminum particles M2), the barrier properties of the UV-curing coating are further significantly improved with sample P22, which consists of only 0.4 wt% aluminum particles M2 but additionally 0.8 wt% Talc LP30, and especially with sample P23, which consists of 0.4 wt% aluminum particles M2 and additionally 1.6 wt% Talc LP30.

[0125] Based on the results obtained, it can therefore be concluded that for transparent and cost-effective coatings, in particular for UV-curing barrier coatings with good UV transparency and the resulting improved curing, as well as for cost optimization purposes, it is advantageous to use mixtures of metal and non-metallic nanoscale thick platelet-shaped particles in barrier layers according to the invention.

[0126] The results obtained can be transferred to other coating matrices, coating systems and matrix polymers, so that mixtures of metal and non-metallic nanoscale thick platelet-shaped particles can be used advantageously in barrier layers where cost optimization combined with transparency and efficient barrier properties is particularly important.

Claims

[1] Composition for the production of a barrier layer, comprising a polymer component, surface-modified inorganic particles in the form of metal particles, which are corrosion-passivated nanoscale platelet-shaped aluminium particles, and a proportion of an organic solvent, wherein the particles are modified on their surface with one or more double bond functionally reactive silane components and with one or more amino functional components, wherein the amino functional component(s) is / are selected from a multifunctional low molecular weight aliphatic, aromatic, heterocyclic component, amino functional polyether components and mixtures thereof; wherein the particles have a nanoscale platelet thickness; and wherein the polymer component is selected from polyacrylates, polyvinylidene chlorides, polyurethanes, polyesters and cellulose derivatives. [2] Composition according to claim 1, wherein the organic solvent comprises a reactive diluent. [3] Composition according to one of claims 1 to 2, wherein the platelet-shaped particles have an average thickness of 10 nm to 200 nm, preferably of 20 nm to 100 nm and more preferably of 20 nm to 80 nm. [4] Composition according to any one of claims 1 to 3, wherein the double bond functional reactive silane component is an olefinically reactive silane component, which is preferably selected from vinyltrimethoxysilane and 3-methacryloxypropyltrimethoxysilane and mixtures thereof. [5] Composition according to any one of claims 1 to 4, wherein the proportion of platelet-shaped particles in the composition is 0.1 to 60 wt.%, in particular 1 to 40 wt.% and more preferably 1 to 30 wt.%, based on the proportion of the polymer component. [6] Composition according to any one of claims 1 to 5, wherein the composition comprises nanoscale thick platelet-shaped silicate particles in a proportion of 0.1 wt.% to 8 wt.%, based on the proportion of the polymer component, and further comprising a proportion of nanoscale thick platelet-shaped aluminium particles in a weight ratio of aluminium particles to silicate particles in the range of 100:1 to 1:

5. [7] Composition according to any one of claims 1 to 6, wherein the composition for generating a barrier effect against the permeation of water and water vapor comprises 30 wt.% to 60 wt.%, preferably 50 wt.% to 58 wt.% of the surface-modified nanoscale thick aluminum particles, based on the proportion of the polymer component. [8] Barrier layer obtained from a composition according to one of claims 1 to 7, comprising a layer having a dry film thickness of 0.1 to 20 µm, comprising the surface-modified platelet-shaped particles which are embedded in a polymer matrix of the polymer component. [9] Barrier layer according to claim 8, wherein the dry film thickness is 0.5 to 10 µm, preferably 0.5 to 6 µm. [10] Barrier layer according to claim 8 or 9, wherein the layer is thermally and / or UV cross-linked by the inclusion of a reactive diluent. [11] Barrier layer according to claim 10, wherein the barrier coating is overcoated with one or more thicker, particle-free, thermoset layers with a layer thickness of 4 µm to 60 µm, preferably 10 µm to 40 µm, more preferably 15 µm to 25 µm. [12] Barrier layer according to one of claims 8 to 11, wherein the barrier layer comprises a surface layer 10 µm to 40 µm, in particular 15 µm to 25 µm thick, preferably particle-free, and an underlying layer 0.5 µm to 6 µm, in particular 0.7 µm to 1 µm thick, surface-modified, nanoscale thick platelet-shaped particles thick. [13] Barrier layer according to claim 12, wherein the underlying layer contains 30 wt.% to 60 wt.% surface-modified nanoscale thick platelet-shaped particles, based on the proportion of the polymer component. [14] Barrier layer according to one of claims 8 to 12, wherein the layer comprising the surface-modified, nanoscale thick platelet-shaped particles comprises a proportion of 1 wt.% to 30 wt.% of the surface-modified, nanoscale thick aluminium particles and preferably further a proportion of 0.1 wt.% to 8 wt.% of surface-modified, nanoscale thick silicate particles, in each case based on the proportion of the polymer component. [15] Barrier layer according to one of claims 8 to 14, wherein the barrier layer comprises additional white or black pigments and is formulated in particular as color-neutral white or dark and further preferably has no metallic effects. [16] Use of a composition according to any one of claims 1 to 7 for producing a barrier layer on a substrate. [17] Use according to claim 16 for producing a barrier layer on metal, paper, cardboard and plastic substrates and combinations thereof, in particular for producing a barrier layer on plastic packaging and molded parts, more preferably on plastic cartridges, plastic capsules, plastic films and plastic bottles, which are preferably based on polyamide (PA), polyethylene (HDPE, LDPE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), polyacrylate, polyester, polylactide (PLA) and polycarbonate (PC). [18] Use according to claim 16 or 17, wherein at least one barrier layer of a multilayer structure with several different layers and / or a multilayer structure with several identical layers is produced from the composition, preferably on metal or plastic surfaces and more preferably on two opposite sides, for example on the inside and outside of molded bodies or films. [19] Substrate coated with a barrier layer in the form of a shaped body, a hollow body, a planar substrate or a film with a barrier layer applied inside and / or outside according to any one of claims 8 to 15. [20] Method for applying a barrier layer to a substrate, the method comprising the steps: - Providing a composition according to any one of claims 1 to 7; and - Applying the composition to a surface of the substrate using a squeegee or a printing process; wherein the substrate is preferably a film, in particular a packaging film.

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