Fiber-based packaging material with a barrier layer and special moisture barrier

Abstract

Oxygen permeability of 1.1 cm measured according to DIN 53380-3 at 23°C and 85% relative humidity 3 / (m 2 ·d·bar) and a water vapor permeability of less than 1.1 g / (m) measured at 23°C and 85% relative humidity according to ISO 15106-2 2 The fiber-based packaging material (10) has a viscosity of less than d) and comprises a substrate layer (12) containing fiber materials, a cover layer (20) formed in a dry state from an aqueous dispersion of a polymer to a content of at least 90% by weight, and a barrier layer (16) consisting of a metal oxide deposited from the gas phase, the barrier layer (16) being located between the cover layer (20) and the substrate layer (12). Additionally, between the cover layer (20) and the substrate layer (12) are arranged a first polymer layer (14) formed in a content of at least 90% by weight from a first polymer and a second polymer layer (18) formed in a content of at least 90% by weight from a second polymer, the first polymer and the second polymer having different wettabilities with distilled water according to DIN EN 828.

Description

[Technical Field]

[0001] The present invention has an oxygen permeability of 1.1 cm , measured according to DIN 53380-3 at 23°C and 85% relative humidity. 3 / (m 2 ·d·bar) and a water vapor permeability of 1.1 g / (m) measured according to ISO 15106-2 at 23°C and 85% relative humidity. 2 d) packaging materials based on textile raw materials that are less than [Background technology]

[0002] The packaging material includes a substrate layer containing a fibrous material, which preferably forms the base layer of the entire multi-layer packaging material.

[0003] The above-mentioned barrier properties of oxygen permeability, also known in the art as "OTR" (Oxygen Transfer Rate), and water vapor permeability, also known in the art as "WVTR" (Water Vapor Transfer Rate), are obtained in textile-based packaging materials by incorporating a barrier layer consisting of a metal oxide preferentially deposited from the gas phase into the layer structure of the packaging material.

[0004] A cover layer is disposed on the barrier layer to protect it from mechanical loads or to provide a sealable layer, i.e., the barrier layer is located between the cover layer and the substrate layer, and the cover layer is formed, in a dry state, of at least 90% by weight from an aqueous dispersion of a polymer.

[0005] The substrate layer containing fibrous materials is preferably a fibrous nonwoven fabric formed by dewatering a fiber suspension, compressed, and dried. The fibers of the fibrous material are preferably made of pulp, wood pulp, or recycled paper. The substrate layer containing fibrous materials is more preferably a paper layer or cardboard layer. Therefore, the substrate layer containing fibrous materials is usually absorbent and absorbs liquids on contact without further treatment.

[0006] From the prior art it is known to subject textile-based packaging materials to a metallization treatment in order to provide the packaging material with the desired barrier against the transmission of oxygen and water vapor through the packaging material.

[0007] A drawback of the above-mentioned metallization process is its opacity and metallic luster, which can cause the packaging material to be mistaken for metal foil and, as a result, not be fed into established recycling routes.

[0008] In contrast, the barrier layer using the vapor-deposited metal oxide layer described above is transparent, so the nature of the packaging material is not hidden or obscured by the barrier layer, facilitating proper feeding of the packaging material into designated recycling routes.

[0009] However, the metal oxide layer deposited from the vapor phase is thinner than known metallization processes—in some cases, only one-quarter the thickness of typical metallization processes—which can limit the hermeticity of the barrier layer, especially if the substrate layer containing the fibrous material is porous and has pores large enough relative to the thickness of the metal oxide barrier layer.

[0010] Therefore, during application of the above-mentioned cover layer formed as an aqueous dispersion to avoid mechanical damage to the barrier layer or to provide a sealable layer, moisture from the applied cover layer dispersion can penetrate the metal oxide barrier layer and reach the substrate layer comprising fibrous materials. Moisture absorbed by the substrate layer can cause the substrate layer to swell, particularly when the substrate layer comprising fibrous materials is a paper or cardboard layer in a preferred embodiment, and can cause serious damage to the entire packaging material formed therefrom. Summary of the Invention [Problem to be solved by the invention]

[0011] Therefore, the object of the present invention is to further develop the above-mentioned flat packaging material based on fiber materials, which has a substrate layer containing fiber materials, a cover layer, and a barrier layer consisting of a metal oxide deposited from the gas phase and arranged between the substrate layer and the cover layer, in such a way that the above-mentioned disadvantages are reduced or completely avoided. [Means for solving the problem]

[0012] The present invention solves this problem in a flat packaging material based on fiber materials of the type mentioned at the beginning by additionally disposing a first polymer layer and a second polymer layer between the cover layer and the substrate layer in the packaging material, the first polymer layer being formed to at least 90% by weight from the first polymer, and the second polymer layer being formed to at least 90% by weight from the second polymer, the first polymer and the second polymer having different wettability with distilled water according to DIN EN 828.

[0013] The main layers of the textile-based packaging material will hereinafter also be referred to in shorthand as "substrate layer", "barrier layer", "cover layer", "first polymer layer" and "second polymer layer", because these abbreviations are also unambiguous.

[0014] By providing an additional polymer layer between the substrate layer and the cover layer, each polymer having a different wettability with respect to water (distilled water is called the reference liquid or reference water, taking into account the cited DIN standard), it is possible to prevent or significantly reduce the migration of moisture (i.e., water) from the cover layer, applied as an aqueous dispersion, through the barrier layer and into the substrate layer containing the fibrous material. Since aqueous dispersions are usually made with distilled water, the liquid base of the reference liquid for determining the wettability of the cover layer during application is the same as that of the dispersion. Even if other than distilled water is used to provide the cover layer dispersion, the difference between the relative wettability of each polymer and its wettability with distilled water is negligible.

[0015] In this application, in various contexts, reference is made to the application of layers as dispersions. Application as dispersions actually relates to the process of application. In all other aspects, the layers are discussed in their dried or dried and solidified final state, i.e., when the water forming the dispersion or the solvent used instead of water has evaporated.

[0016] When the term "solvent" is used in this application, this solvent is distinguished from water, which is also referred to. Thus, a "solvent" in this application is a liquid other than water that is suitable for producing a polymer dispersion.

[0017] DIN EN 828, described in this application, is based on scientifically accepted principles and measures the wettability of materials with distilled water using the contact angle formed by a defined drop of water on the surface of each material. Materials with a water contact angle of greater than 90° are considered hydrophobic. Materials with a small contact angle are considered hydrophilic. Essentially, as the contact angle increases, the observed wettability of the material decreases.

[0018] In the following, it is assumed that the first polymer has better wettability with distilled water than the second polymer, which, according to DIN EN 828, means that the contact angle of a drop of distilled water on wetting the first polymer is smaller than on wetting the second polymer.

[0019] It is generally advantageous if the first polymer is not hydrophobic, i.e., if the contact angle measured in accordance with DIN EN 828 upon wetting with distilled water is less than 90°. Since better wettability than the second polymer is achieved the smaller the contact angle that results upon wetting with distilled water, the first polymer preferably has a contact angle of less than 75°, particularly preferably less than 60°, upon wetting with distilled water in accordance with DIN EN 828. The contact angle of a drop of distilled water upon wetting of the first polymer in accordance with DIN EN 828 can also be significantly less than 60°, for example, in the angle range from 0° to 30°.

[0020] Since the second polymer is desirably poorly wettable by distilled water, the second polymer preferably has a contact angle of greater than 45° when wetted with distilled water, measured according to DIN EN 828. It should be further noted that if the contact angle value given here as the lower limit is smaller than the contact angle given as the upper limit for the first polymer, the contact angle when the first polymer is wetted with distilled water is smaller than the contact angle when the second polymer is wetted with distilled water. Preferably, the contact angle when the second polymer is wetted is greater than 60°, particularly preferably greater than 75°.

[0021] Particularly good results have been obtained with hydrophobic second polymers when preventing water migration from the aqueous dispersion of the subsequent cover layer through the barrier layer to the substrate layer containing fibrous materials. Preferably, the second polymer therefore has a contact angle, measured according to DIN EN 828, of greater than 90° upon wetting with distilled water.

[0022] Because the first polymer layer is more easily wettable with water than the second polymer layer, it is preferable that the first polymer layer be positioned as far away from the cover layer as possible or sandwich as many additional layers as possible between the first polymer layer and the cover layer. This is achieved by a structure in which the first polymer layer is positioned between the substrate layer and the barrier layer. This ensures that at least one barrier layer is always present between the substrate layer and the first polymer layer. Furthermore, because the first polymer layer may provide a smoother surface for the deposition of the metal oxide barrier layer than the substrate layer containing the fiber material, the barrier effect of the metal oxide barrier layer is also increased when the metal oxide barrier layer is deposited on an intermediate polymer layer (e.g., the first polymer layer) rather than directly on the substrate layer.

[0023] Preferably, the first polymer layer is the polymer layer closest to the substrate layer on the side where the barrier layer is disposed. The first polymer layer may be applied directly to the substrate layer. Because the barrier layer is transparent, the surface of the substrate layer on the barrier layer side can be printed by applying a printing ink, and therefore the first polymer layer can be applied directly on top of the printing ink coating.

[0024] The second polymer layer may be disposed essentially between the substrate layer and the barrier layer, or / and between the barrier layer and the cover layer, and may include or be formed from two partial polymer layers.

[0025] When the second polymer layer is disposed between the substrate layer and the barrier layer, the second polymer layer is preferably positioned between the first polymer layer and the barrier layer. This also applies to a partial polymer layer of the second polymer layer. The barrier layer is then deposited on the polymer material of the second polymer layer. Since the second polymer layer or its partial polymer layer is applied to the first polymer layer, a smoother surface can be provided for the deposition of the metal oxide barrier layer.

[0026] For example, the second polymer layer or a partial polymer layer thereof may be applied as an aqueous dispersion, in which case the second polymer layer or a partial polymer layer thereof is preferably disposed between the substrate layer and the barrier layer, and particularly preferably between the first polymer layer and the barrier layer.

[0027] Alternatively, the second polymer layer can be coated and formed as a solvent-based dispersion of the second polymer. When the second polymer layer is composed of at least two or exactly two partial polymer layers, all or both partial polymer layers can be coated and formed as solvent-based dispersions, or one or at least one partial polymer layer can be coated and formed as an aqueous dispersion and one or at least one further partial polymer layer can be coated and formed as a solvent-based dispersion.

[0028] A second polymer layer, or a partial polymer layer thereof, coated as a solvent-based dispersion, is preferably disposed between the barrier layer and the cover layer.

[0029] The first polymer may be a vinyl alcohol-based polymer such as an ethylene-vinyl alcohol copolymer or polyvinyl alcohol. Among these, polyvinyl alcohol is preferred as the first polymer. Compared to other polymers, vinyl alcohol-based polymers provide a particularly high oxygen barrier layer for the same layer thickness in a layer structure such as the packaging material discussed herein, resulting in excessively reduced oxygen permeability of the packaging material.

[0030] The second polymer may be a polyolefin and / or a polyester. This applies particularly when the second polymer layer comprises two partial polymer layers. When the second polymer layer or a partial polymer layer thereof is applied as an aqueous dispersion of the second polymer, the second polymer is preferably a polyolefin, in particular polyethylene or polypropylene. When the second polymer layer or a partial polymer layer thereof is applied as a solvent-based dispersion of the second polymer, the second polymer may be a polyolefin or a polyester.

[0031] The first and second polymer layers are formed from at least 90% by weight of the first and second polymers, respectively, ensuring that the polymer layers have the wetting properties of the first and second polymers, respectively. At least one of the first and second polymer layers, preferably both layers, may be formed from at least 95% by weight, particularly preferably at least 99% by weight, of the first and second polymers, respectively.

[0032] The polymer of the cover layer may include or be an acrylic copolymer or / and a polyolefin or / and an ethylene vinyl acetate copolymer or / and a biopolymer, such as polylactic acid, polyhydroxyalkanoate, starch polymers, or generally cellulose- or starch-based polymers.

[0033] For a particularly resource-efficient and effective formation of the first polymer layer, the first polymer layer may have a coating weight of 1.0 g / m2 measured on a dry basis. 2 ~5.0g / m 2 , especially 1.5 g / m 2 ~3.5g / m 2 It can be formed so that:

[0034] For the same reason, the second polymer layer has a coating weight of 0.5 g / m2 measured in the dry state. 2 ~3.0g / m 2 , especially 1.0 g / m 2 ~2.5g / m 2 It can be formed so that:

[0035] The flat textile-based packaging material discussed here may be part of a packaging material that includes further layers. Preferably, however, the cover layer is the layer that is exposed to the environment. The printing ink coating described above as a preferred variant can be applied to the side of the substrate layer facing away from the barrier layer. One or more further layers can be applied onto the printing ink coating, such as a protective coating layer to protect the printing ink coating from external influences and / or a sealable polymer layer, in particular a polyolefin layer.

[0036] Preferably, the oxygen permeability of the packaging material is less than 1.0 cm when measured at 23°C and 85% relative humidity according to DIN 53380-3. 3 / (m 2 d bar), particularly preferably less than 0.85 cm 3 / (m 2Additionally or alternatively, the water vapor permeability of the packaging material is less than 1.0 g / (m 2 ) when measured according to ISO 15106-2 at 23°C and 85% relative humidity. 2 d), particularly preferably less than 0.85 cm 3 / (m 2 d bar).

[0037] The following defined objects (Ggs) are of particular importance in this application. The features of the objects are marked with reference numerals in the following drawing description.

[0038] Objective (Ggs) 1: Oxygen permeability measured according to DIN 53380-3 at 23°C and 85% relative humidity is 1.1 cm 3 / (m 2 ·d·bar) and a water vapor permeability of less than 1.1 g / (m) measured at 23°C and 85% relative humidity according to ISO 15106-2 2 1. A packaging material (10; 110; 210) based on fiber materials, comprising a substrate layer (12; 112; 212) containing fiber materials, a cover layer (20; 120; 220) in which at least 90% by weight in the dry state is formed from an aqueous dispersion of a polymer, and a barrier layer (16; 116; 216) consisting of a metal oxide deposited from the gas phase, the barrier layer (16; 116; 216) being located between the cover layer (20; 120; 220) and the substrate layer (12; 112; 212), Additionally, a textile-based packaging material (10; 110; 210) is provided, in which a first polymer layer (14; 114; 214) is arranged between the cover layer (20; 120; 220) and the substrate layer (12; 112; 212), the first polymer layer (14; 114; 214) being formed to at least 90% by weight from a first polymer and a second polymer layer (18; 118; 218a, 218b) being formed to at least 90% by weight from a second polymer, the first polymer and the second polymer having different wettabilities with distilled water in accordance with DIN EN 828.

[0039] Object (Ggs) 2: A fiber-based packaging material (10; 110; 210) according to object 1 further developed in that the substrate layer (12; 112; 212) containing fiber materials is a paper or cardboard layer.

[0040] Object (Ggs) 3: A fiber-based packaging material according to object 1 or 2, further developed in that the first polymer, when wetted with distilled water, exhibits a contact angle measured in accordance with DIN EN 828 of less than 90°, preferably less than 75°, particularly preferably less than 60°, and the second polymer, when wetted with distilled water, exhibits a contact angle measured in accordance with DIN EN 828 of more than 45°, preferably more than 60°, particularly preferably more than 75° (10; 110; 210).

[0041] Object (Ggs) 4: Packaging material based on textile materials according to object 3 (10; 110; 210) further developed in that the second polymer exhibits a contact angle, measured according to DIN EN 828, greater than 90° upon wetting with distilled water.

[0042] Object (Ggs) 5: A textile-based packaging material (10; 110; 210) according to any one of objects 1 to 4, further developed in that a first polymer layer (14; 114; 214) is arranged between the substrate layer (12; 112; 212) and the barrier layer (16; 116; 216).

[0043] Object (Ggs) 6: A fiber raw material-based packaging material (110; 210) according to any one of objects 1 to 5, further developed in that a second polymer layer (118; 218b) is arranged between the substrate layer (112; 212) and the barrier layer (116; 216) as an aqueous dispersion of a second polymer.

[0044] Object (Ggs) 7: A textile-based packaging material (110; 210) according to objects 5 and 6, further developed by the fact that a second polymer layer (118; 218b) is arranged between the first polymer layer (114; 214) and the barrier layer (116; 216) as an aqueous dispersion of the second polymer.

[0045] Object (Ggs) 8: A fiber raw material-based packaging material (10; 210) according to any one of objects 1 to 7, further developed in that a second polymer layer (18; 218a) is arranged between the barrier layer (16; 216) and the cover layer (20; 220) as a solvent-based dispersion of the second polymer.

[0046] Subject (Ggs) 9: A textile-based packaging material according to any one of subjects 1 to 8, further developed by the fact that the first polymer is a vinyl alcohol-based polymer (10; 110; 210).

[0047] Target (Ggs) 10: A fiber-based packaging material according to any one of targets 1 to 9, citing at least one of targets 6 and 7, further developed by the fact that the second polymer is a polyolefin (110; 210).

[0048] Subject (Ggs) 11: A packaging material based on fiber raw materials according to any one of subjects 1 to 10, citing subject 8, further developed by the fact that the second polymer is a polyolefin or polyester (10;210).

[0049] Object (Ggs) 12: A packaging material (10; 110; 210) based on fiber raw materials according to any one of objects 1 to 11, further developed in that the polymer of the cover layer (20; 120; 220) comprises an acrylic copolymer or / and a polyolefin or / and an ethylene vinyl acetate copolymer, or is a biopolymer.

[0050] Control (Ggs) 13: The first polymer layer (14; 114; 214) has a dry coating weight of 1.0 g / m2 ~5.0g / m 2 A textile-based packaging material according to any one of objects 1 to 12, further developed by being formed to be (10; 110; 210).

[0051] Subject (Ggs) 14: The second polymer layer (18; 118; 218a, 218b) had a dry coating weight of 0.5 g / m 2 ~3.0g / m 2 A textile-based packaging material (10; 110; 210) according to any one of objects 1 to 13, further developed by being formed to be

[0052] Object (Ggs) 15: A textile-based packaging material (10; 110; 210) according to any one of objects 1 to 14, further developed in that the metal oxide of the barrier layer (16; 116; 216) is aluminum oxide or silicon oxide.

[0053] The invention will now be described in detail with reference to the accompanying drawings, in which: [Brief explanation of the drawings]

[0054] [Figure 1] 1 shows a cross-section of a first embodiment of a flat packaging material according to the invention; [Figure 2] 1 shows a cross-section of a second embodiment of a flat packaging material according to the invention; [Figure 3] 1 shows a cross-section of a third embodiment of a flat packaging material according to the invention; DETAILED DESCRIPTION OF THE INVENTION

[0055] 1 shows a first embodiment of a flat, fibrous-based packaging material according to the invention in cross section and is generally designated by the reference number 10. The packaging material comprises a fibrous-based substrate layer 12, preferably of 40 g / m 2 from 200 g / m 2The paper layer as the fiber-based substrate layer 12 may be a layer of coated or uncoated paper.

[0056] A first polymer layer 14 containing polyvinyl alcohol as the preferred first polymer in an aqueous dispersion is applied to one side of the substrate layer 12. In the first embodiment shown, the aqueous dispersion of polyvinyl alcohol is applied directly to the substrate layer 12.

[0057] The coating weight of the first polymer layer 14 is 1.0 g / m 2 ~5.0g / m 2 and preferably about 3.5 g / m 2 The first polymer layer 14 not only provides a smoother surface on the side of the substrate layer 12 to which it is applied than the substrate layer 12 itself, but also significantly reduces the oxygen permeability of the entire packaging material 10.

[0058] Polyvinyl alcohol absorbs water and is therefore easily wettable by water (even distilled water).

[0059] A barrier layer 16, preferably made of aluminum oxide, is deposited by vacuum deposition on the first polymer layer 14. Barrier layer 16 having a thickness of less than 1 μm, especially less than 0.5 μm, forms an excellent barrier layer for reducing the oxygen and water vapor permeability of packaging material 10.

[0060] A second polymer layer 18 containing a second polymer as a solvent-based dispersion is applied to the barrier layer 16, i.e., the side of the barrier layer 16 opposite the first polymer layer 14. Because the solvent-based dispersion of the second polymer layer 18 does not contain water, application of the solvent-based dispersion does not adversely affect the first polymer layer 14, which is made of polyvinyl alcohol.

[0061] The second polymer of the second polymer layer 18 is less wettable by distilled water than the polyvinyl alcohol of the first polymer layer 14. The second polymer, in the first illustrated embodiment, may be a polyolefin, such as polypropylene or polyethylene, or a polyester, such as polyethylene terephthalate.

[0062] The layer structure consisting of the first polymer layer 14, the barrier layer 16 and the second polymer layer 18 is protected from external mechanical influences by a cover layer 20, preferably applied as an aqueous dispersion of polymer to the second polymer layer 18, more precisely to its side facing away from the barrier layer 16. The cover layer 20 is thus likewise a polymer layer and consists, for example, of an acrylic copolymer.

[0063] The second polymer layer 18 has a density of 0.5 g / m 2 to 3.0 g / m 2 Coating weight in the range of 2.0 g / m 2 The coating is applied at a coating weight of 1000 ppm.

[0064] The packaging material 10 of the first embodiment has a thickness of 1.0 cm measured at 23°C and 85% relative humidity in accordance with DIN 53380-3. 3 / (m 2 d bar) and has an oxygen transmission rate of 1.0 g / (m) measured at 23°C and 85% relative humidity according to ISO 15106-2 2 d) Water vapor permeability.

[0065] 2 shows a cross-section of a second embodiment of the packaging material according to the present invention. In the following, the second embodiment will be described only in terms of the differences from the first embodiment. Components and parts of components that are identical and have the same functions as those in the first embodiment are given the same reference symbols in the second embodiment, but with the numbers increased by 100. For the rest of the description of the second embodiment, reference is made to the description of the first embodiment.

[0066] It should be particularly clear with the second embodiment that the first polymer layer 114 does not necessarily have to be applied directly to the substrate layer 112, which may for example be printable and thus support a coating of printing ink 122. On top of this coating of printing ink the first polymer layer 114 may be applied as an aqueous dispersion of polyvinyl alcohol.

[0067] Furthermore, in the second embodiment, the second polymer layer 118 is formed between the first polymer layer 114 and the aluminum oxide barrier layer 116. In the second embodiment, the second polymer layer 118 is applied as an aqueous dispersion of the second polymer rather than as a solvent-based dispersion of the second polymer. Thus, in the second embodiment, the second polymer is preferably a polyolefin. The coat weight of the second polymer layer 118 corresponds to the coat weight in the first embodiment.

[0068] Thus, a barrier layer 116 of aluminum oxide is deposited on the second polymer layer 118 from the gas phase in a vacuum.

[0069] The cover layer 120 still forms the exposed layer towards the periphery of the packaging material 110 .

[0070] 3 shows a cross-section of a third embodiment of the packaging material according to the present invention. In the following, the third embodiment will be described only in terms of the differences from the first embodiment. Components and parts of components that are identical and have the same function as those in the first embodiment are given the same reference symbols in the third embodiment, but with the number increased by 200. Otherwise, for the description of the third embodiment, reference is made to the descriptions of the first and second embodiments.

[0071] The third embodiment of the packaging material 210 corresponds to a combination of the first two embodiments, but for ease of explanation, it is not provided with a coating of printed ink, as in the first example.

[0072] Substrate layer 212 and first polymer layer 214 correspond to substrate layers 12 and 112 and first polymer layers 14 and 114 in the first and second embodiments, respectively. Similarly, aluminum oxide barrier layer 216 corresponds to barrier layers 16 and 116 in the first and second examples, respectively.

[0073] In the third embodiment, the second polymer layer 218 is composed of two partial polymer layers, including a partial polymer layer 218a disposed as a solvent-based dispersion of polyolefin or polyester between the barrier layer 216 and the cover layer 220, similar to the first embodiment.

[0074] The second polymer layer 218 further includes a partial polymer layer 218b, similar to the second embodiment, applied as an aqueous dispersion of polyolefin between the first polymer layer 214 and the barrier layer 216. The aluminum oxide barrier layer 216 is deposited on the partial polymer layer 218b.

[0075] The packaging materials 10 and 210 of the first and third embodiments may have a coating layer of printed ink, for example, to add consumer information to the packaging material. The coating layer of printed ink may be applied, as in the second embodiment, on the substrate layer 12 or 212, between the substrate layer 12 or 212 and the first polymer layer 14 or 214, or / and on the surface of the substrate layer 12 or 212 opposite the barrier layer 16 or 216.

[0076] In the third embodiment, each partial polymer layer 218a and 218b may have, by itself, the coating weight described for the second polymer layers 18 and 118 in the first and second embodiments. Alternatively, the two partial polymer layers 218a and 218b may together have the coating weight described for the second polymer layers 18 and 118 in the first and second embodiments. [Explanation of symbols]

[0077] 10, 110, 210 Packaging materials 12, 112, 212 board layers 14, 114, 214 First polymer layer 16, 116, 216 Barrier layer 18, 118, 218, 218a, 218b Second polymer layer 20, 120, 220 cover layers 122 Printing ink coating

Claims

1. Oxygen permeability measured according to DIN 53380-3 at 23 ° C and 85% relative humidity is 1.1 cm ３ / (m ２ d bar) and a water vapor permeability of 1.1 g / (m) measured according to ISO 15106-2 at 23°C and 85% relative humidity. ２ a packaging material (10; 110; 210) based on fiber materials, the packaging material (10; 110; 210) being less than d) and comprising a substrate layer (12; 112; 212) comprising fiber materials, a cover layer (20; 120; 220) which in the dry state is formed from an aqueous dispersion of a polymer to an extent of at least 90% by weight, and a barrier layer (16; 116; 216) consisting of a metal oxide deposited from the gas phase, the barrier layer (16; 116; 216) being located between the cover layer (20; 120; 220) and the substrate layer (12; 112; 212), Additionally, a first polymer layer (14; 114; 214) formed to at least 90% by weight from a first polymer and a second polymer layer (18; 118; 218a, 218b) formed to at least 90% by weight from a second polymer are arranged between the cover layer (20; 120; 220) and the substrate layer (12; 112; 212), the first polymer and the second polymer having different wettabilities with distilled water according to DIN EN 828, the contact angle of a drop of distilled water on wetting the first polymer being smaller than the contact angle on wetting the second polymer, A packaging material (10; 110; 210) based on fiber raw materials, characterized in that the first polymer layer (14; 114; 214) is arranged between the substrate layer (12; 112; 212) and the barrier layer (16; 116; 216), and the second polymer layer (18; 118; 218a, 218b) is arranged between the first polymer layer (14; 114; 214) and the barrier layer (16; 116; 216) or / and between the barrier layer (16; 116; 216) and the cover layer (20; 120; 220).

2. 2. Packaging material (10; 110; 210) based on fiber materials according to claim 1, characterized in that the substrate layer (12; 112; 212) containing fiber materials is a paper or cardboard layer.

3. 3. Packaging material (10; 110; 210) based on fiber materials according to claim 1 or 2, characterized in that the first polymer, upon wetting with distilled water, exhibits a contact angle, measured in accordance with DIN EN 828, of less than 90°, preferably less than 75°, particularly preferably less than 60°, and the second polymer, upon wetting with distilled water, exhibits a contact angle, measured in accordance with DIN EN 828, of more than 45°, preferably more than 60°, particularly preferably more than 75°.

4. 4. Packaging material (10; 110; 210) based on fiber materials according to claim 3, characterized in that the second polymer exhibits a contact angle, measured according to DIN EN 828, on wetting with distilled water of more than 90°.

5. 5. A packaging material (110; 210) based on fiber raw materials according to any one of claims 1 to 4, characterized in that the second polymer layer (118; 218b) is arranged between the substrate layer (112; 212) and the barrier layer (116; 216) as an aqueous dispersion of the second polymer.

6. 6. The fiber-based packaging material (110; 210) according to claim 5, characterized in that the second polymer layer (118; 218b) is arranged between the first polymer layer (114; 214) and the barrier layer (116; 216) as an aqueous dispersion of the second polymer.

7. 7. A fiber-based packaging material (10; 210) according to any one of claims 1 to 6, characterized in that the second polymer layer (18; 218a) is arranged between the barrier layer (16; 216) and the cover layer (20; 220) as a solvent-based dispersion of the second polymer.

8. 8. Packaging material (10; 110; 210) based on textile materials according to any one of claims 1 to 7, characterized in that the first polymer is a vinyl alcohol-based polymer.

9. Packaging material (110; 210) based on fiber raw materials according to any one of claims 1 to 8, when taking into account at least one of claims 5 and 6, characterized in that the second polymer is a polyolefin.

10. Packaging material (10; 210) based on fiber materials according to any one of claims 1 to 9, when taken in conjunction with claim 7, characterized in that the second polymer is a polyolefin or a polyester.

11. 11. Packaging material (10; 110; 210) based on fiber raw materials according to any one of claims 1 to 10, characterized in that the polymer of the cover layer (20; 120; 220) comprises an acrylic copolymer or / and a polyolefin or / and an ethylene vinyl acetate copolymer, or is a biopolymer.

12. The first polymer layer (14; 114; 214) has a coating weight measured in the dry state of 1.0 g / m ２ ~5.0g / m ２ 12. Packaging material (10; 110; 210) based on textile materials according to any one of claims 1 to 11, characterized in that it is formed so that:

13. The second polymer layer (18; 118; 218a, 218b) has a coating weight measured in the dry state of 0.5 g / m ２ ~3.0g / m ２ 13. Packaging material (10; 110; 210) based on textile materials according to any one of claims 1 to 12, characterized in that it is formed so that:

14. 14. Packaging material (10; 110; 210) based on textile materials according to any one of claims 1 to 13, characterized in that the metal oxide of the barrier layer (16; 116; 216) is aluminium oxide or silicon oxide.

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