Paper-based multilayer packaging film

Abstract

The present disclosure relates to a multilayer packaging film and a method of producing the same. The multilayer packaging film is paper-based and has a total composition comprising greater than or equal to 80% by weight of paper components. The multilayer packaging film can be readily recycled by re-pulping while still maintaining high performance packaging properties, including maintaining permeability properties and controlling the rate of ripening of living food products such as cheese products. For example, cheese products may include, but are not limited to, soft cheese and / or breathable cheese.

Description

Technical Field

[0001] The present disclosure relates to paper-based packaging films and methods of producing the same. Embodiments of the present disclosure relate to paper-based multilayer packaging films having greater than or equal to 80% by weight of a paper component suitable for packaging food products, such as cheese products. Background Art

[0002] The goal of increasing the recyclability of paper-based multilayer packaging films becomes challenging when attempting to form films intended to protect packaged products, such as food products, from their external environment. Traditionally, packaged products have been protected by forming multilayer films having a plurality of specific layers. As performance requirements increase, the number of layers or thickness of each layer in the multilayer film increases, which will be detrimental to the recyclability of the structure as the paper content in percentage terms decreases.

[0003] Typically, when high performance is required for paper-based multilayer packaging films, relatively large amounts of additional non-paper materials are added to the paper-based packaging films. In order to maintain the recyclability of the paper-based packaging films, the paper component thickness and / or weight is increased in order to obtain the paper content required to designate the packaging material as "recyclable".

[0004] In addition, for food products, it is desirable to form a packaging film that regulates and optimizes the air permeability, gas permeability, water vapor permeability and water absorption capacity between the food product and the external environment during the ripening process of the food product in the package. However, current multilayer films that provide some desired permeability properties usually have a relatively high amount of other non-paper materials added to the film, such as paraffin, which acts to prevent the mold present on the cheese product from adhering to the multilayer film. Because its use may cause health problems, it is not encouraged to use paraffin in the food packaging industry. Therefore, it is desirable to avoid the presence of paraffin when developing food packaging.

[0005] Without questioning the relative advantages of prior art systems, there exists a need for a paper-based multilayer packaging film that is paraffin-free, suitable for recycling, maintains permeability properties, and has the ability to control the ripening rate of food products, such as cheese products. Summary of the invention

[0006] Embodiments of the present disclosure relate to flexible paper-based multilayer packaging films having high permeability properties and the ability to control the ripening rate of food products such as cheese products while maintaining recyclability in a paper recycling (repulpability) process. As used herein, the terms "one or more paper-based multilayer packaging films" and "one or more paper-based packaging films" are used interchangeably. The paper-based multilayer packaging film includes a paper component and includes a minimal amount of non-paper material. The minimal amount of non-paper material can be easily removed from the paper-based packaging film so that the paper recycling (repulpability) process is not hindered.

[0007] The multilayer packaging film is intended for packaging food products, including but not limited to cheese products. The multilayer packaging film can be used to package moisture-sensitive cheese products, and the packaging controls moisture and / or exudates from the product after being packaged. For example, cheese products may include but are not limited to soft cheese and / or breathable cheese.

[0008] In some embodiments, a paper-based multilayer packaging film includes a polymer layer facing the food product to be packaged, a water-absorbing layer including a paper component, and an adhesive layer attaching the polymer layer to the water-absorbing layer.

[0009] In some embodiments, the total composition of the paper-based multilayer packaging film includes greater than or equal to 80 wt% of the paper component. In some embodiments, the total composition of the paper-based multilayer packaging film includes greater than or equal to 85 wt%, or greater than or equal to 90 wt% of the paper component.

[0010] In some embodiments, the paper component has a 2 Up to 100g / m 2 In some embodiments, the basis weight of the paper component is 20 g / m 2 Up to 60g / m 2 within the range.

[0011] In some embodiments, the paper-based multilayer packaging film includes less than or equal to 20 wt%, less than or equal to 15 wt%, or less than or equal to 10 wt% of non-paper materials. The polymer layer, adhesive layer, and / or print layer may include non-paper materials.

[0012] In some embodiments, the absorbent layer comprising the paper component has a water absorption capacity of 0.01 g / m 2 Up to 30g / m 2 Water absorption within the range of .

[0013] In some embodiments, the polymer layer has a plurality of micro-cuts and the multilayer packaging film has an air permeability in the range of 0.1 mL / min Bendtsen to 200 mL / min Bendtsen, including all ranges and subranges therebetween, measured using the method disclosed in International Standard ISO 5636-3. Exemplary air permeabilities include 10 to 200 mL / min Bendtsen, 15 to 200 mL / min Bendtsen, 20 to 200 mL / min Bendtsen, 50 to 200 mL / min Bendtsen, 0.1 to 50 mL / min Bendtsen, 0.1 to 20 mL / min Bendtsen, 0.1 to 15 mL / min Bendtsen, 0.1 to 10 mL / min Bendtsen, 0.1 to 5 mL / min Bendtsen, 0.1 to 4 mL / min Bendtsen, 0.1 to 3 mL / min Bendtsen, 0.1 to 2 mL / min Bendtsen, 0.1 to 1 mL / min Bendtsen, and 0.1 to 0.5 mL / min Bendtsen. The air permeability of the multilayer packaging film can vary based on the type of food product to be packaged. For example, the multilayer packaging film has an air permeability in the range of 0.1 mL / min Bendtsen to 0.5 mL / min Bendtsen for packaging some types of food products, such as, for example, blue mold soft cheese with a white mold surface. In other embodiments, the multilayer packaging film has an air permeability in the range of 50 mL / min Bendtsen to 200 mL / min Bendtsen for packaging some types of food products, such as, for example, medium-hard cheese with a surface spread.

[0014] In some embodiments, the plurality of micro-cuts are randomly distributed. As used herein, the term "randomly distributed" means that the distance between two adjacent micro-cuts taken in the plane of the polymer layer is not constant. The micro-cuts do not define a periodically repeating pattern, at least on a surface of the inner layer having an area substantially equal to the effective surface of the tool used to make the micro-cuts. The micro-cuts may define any suitable shape. The size of the micro-cuts in the plane of the polymer layer may vary from one micro-cut to another.

[0015] In some embodiments, the plurality of micro-cuts define a pattern in which the distance between one or more adjacent micro-cuts taken in the plane of the polymer layer is not substantially constant, such that the size of the micro-cuts in the plane of the polymer layer may still vary from one micro-cut to another. As used in this context, "substantially non-constant" means that the plurality of micro-cuts as a whole do not define a periodically repeating pattern, but rather a small number of adjacent micro-cuts in the plurality of micro-cuts (e.g., less than 10%, less than 5%, or less than 1% of the plurality of micro-cuts) define a periodically repeating pattern.

[0016] In some embodiments, the micro-incision includes multiple perforations that completely penetrate the polymer layer, that is, the perforations extend through the thickness of the polymer layer. In some embodiments, the micro-incision includes multiple wears that do not completely penetrate the polymer layer, that is, the depth of the wear is less than the thickness of the polymer layer. In some embodiments, the micro-incision has different depths, including multiple perforations extending through the thickness of the polymer layer and multiple wears with a length less than the thickness of the polymer layer. The multiple perforations and multiple wears advantageously allow moisture to be evacuated from food products (e.g., cheese products). Advantageously, the paper-based multilayer packaging film described herein absorbs water from cheese products. In some embodiments, one or more of the multiple perforations or multiple wears are randomly distributed. In some embodiments, the multiple wears are randomly distributed. In addition to the random distribution of the micro-incisions, the penetration depth of the micro-incisions is also random.

[0017] In certain embodiments, the thickness of polymer layer is in the range of 2 μm to 10 μm. In certain embodiments, polymer layer includes one or more of oriented polyethylene (OPE) film, oriented polypropylene (OPP) film, oriented polyester-based polymer film or compostable polymer film. Examples of compostable polymer films include but are not limited to PBAT polymer, PLA polymer, PBT polymer or blends of these polymers. In certain embodiments, polymer layer is biaxially oriented polypropylene (BOPP) film. Oriented polyethylene (OPE) film, oriented polypropylene (OPP) film, oriented polyester-based polymer film and / or compostable polymer film can be bio-based polymer film. In certain embodiments, polymer layer includes multiple layers.

[0018] In some embodiments, the adhesive layer comprises one or more solvent-based adhesives, water-based adhesives, or solvent-free adhesives. In some embodiments, the dry basis weight of the adhesive layer is 0.1 g / m 2 Up to 6g / m 2 In some embodiments, the dry basis weight of the adhesive layer is 0.3 g / m 2 Up to 5g / m 2 In some embodiments, the dry basis weight of the adhesive layer is 0.5 g / m2 Up to 4g / m 2 within the range.

[0019] In some embodiments, the adhesive layer is in direct contact with the water absorbing layer and the polymer layer.

[0020] In one or more embodiments, the adhesive layer is patterned. For example, when the dry basis weight of the adhesive layer is low, such as less than or equal to 0.3 g / m 2 In one or more embodiments, the surface area coverage (e.g., the surface area covered by the adhesive layer) can be in the range of 2% to 100%, such as in the range of 20% to 50%, for example. Without intending to be bound by theory, it is believed that the use of a patterned adhesive layer facilitates recycling, reduces material usage, and is an advantage of adhesive lamination over extrusion lamination (which, by the very nature of the process, requires full coverage).

[0021] In some embodiments, the paper-based multilayer packaging film includes a printing layer on the outer surface (ie, exposed surface) of the water-absorbent layer. In some embodiments, the printing layer faces away from the food product to be packaged.

[0022] Additional embodiments relate to a method of producing a paper-based multilayer packaging film. In some embodiments, the method includes producing a polymer layer; abrading the polymer layer; and attaching the polymer layer to the water-absorbing layer by an adhesive lamination process to produce a multilayer packaging film. In some embodiments, the adhesive lamination process is performed before abrading the polymer layer. In other embodiments, the adhesive lamination process is performed after abrading the polymer layer.

[0023] Further embodiments relate to a package formed by a multilayer packaging film. In one or more embodiments, a package is formed by a multilayer packaging film by wrapping the multilayer packaging film around a food product such as a cheese product and adhering a polymer layer to the outer surface of a water-absorbing layer. In other words, when the multilayer packaging film is wrapped around the food product, the polymer layer and the water-absorbing layer or printed layer will overlap and contact each other, with the polymer layer defining the inner surface of the package and in direct contact with the cheese product and the water-absorbing layer or printed layer defining the outer surface and facing away from the cheese product. For example, a parcel package having a cheese product therein may include a sticker on the outer surface of the package. In other embodiments, a parcel package having a cheese product therein may include a sticker on the outer surface of the package, which may then be placed in a carton. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present disclosure may be more fully understood by considering the following detailed description of various embodiments of the present disclosure in conjunction with the accompanying drawings, in which:

[0025] Figure 1A process flow chart illustrating a method for producing a paper-based multilayer packaging film according to one or more embodiments is shown;

[0026] Figure 2 and Figure 3 Schematic cross-sectional views of various embodiments of paper-based multilayer packaging films are illustrated;

[0027] Figure 4 Indicated Figure 2 and Figure 3 Various embodiments of patterned adhesive layers of paper-based multilayer packaging films shown in; and

[0028] Figure 5 Indicates including Figure 2 and Figure 3 Schematic cross-sectional view of a package of a paper-based multilayer packaging film shown in FIG.

[0029] The accompanying drawings show some but not all embodiments. The elements depicted in the drawings are schematic and not necessarily drawn to scale, and the same (or similar) reference numerals represent the same (or similar) features throughout the drawings. DETAILED DESCRIPTION

[0030] Provided herein are paper-based multilayer packaging films that overcome the shortcomings of previously provided films. The paper-based packaging films of the present disclosure are uniquely designed to provide an important combination of: 1) recyclability (high paper content), 2) ease of packaging conversion, 3) maintaining permeability properties, and 4) controlling the ripening rate of food products such as cheese products. In addition, this unique combination of layers and materials allows for an overall high paper content and low thickness.

[0031] The paper-based packaging film may include additional layers. The combination of these materials may be described as a multilayer film (e.g., a structure or laminate). As used herein, the term "layer" refers to the building blocks of a film. A layer is a structure of a single material type or a uniform blend of materials. A layer may be a single polymer, a blend of materials within a single polymer type, or a blend of various polymers. A layer may contain a metallic material and may have additives. A layer may be continuous with the film, or may be discontinuous or patterned. Both layers and films have a relatively insignificant thickness (z direction) compared to their respective length and width (xy direction).

[0032] As described herein, the "total composition" of a paper-based packaging film refers to all materials included therein. The total composition of a paper-based packaging film may include greater than or equal to 80% by weight of a paper component. The total composition of a paper-based packaging film may include greater than or equal to 85% by weight of a paper component. The total composition of a paper-based packaging film may include greater than or equal to 90% by weight of a paper component. For example, the total composition of a paper-based packaging film may include a paper component in the range of greater than or equal to 80% by weight to greater than or equal to 90% by weight, including all values ​​and subranges therebetween.

[0033] The total composition of the paper-based packaging film may include less than or equal to 20% by weight, less than or equal to 15% by weight, less than or equal to 10% by weight, less than or equal to 5% by weight, less than or equal to 4% by weight, less than or equal to 3% by weight, less than or equal to 2% by weight, or less than or equal to 1% by weight of non-paper materials. The polymer layer, adhesive layer and / or printing layer may include non-paper materials. For example, the total composition of the paper-based packaging film may include 90% by weight of paper components and 10% by weight of non-paper materials. In another example, the total composition of the paper-based packaging film may include a paper component in the range of 80% by weight to 90% by weight (including all values ​​and sub-ranges therebetween) and a non-paper material in the range of 10% by weight to 20% by weight (including all values ​​and sub-ranges therebetween).

[0034] The paper-based multilayer packaging films described herein include a polymer layer defining an inner surface of the film. The paper-based multilayer packaging films described herein include an adhesive layer attaching the polymer layer to the water-absorbing layer. In some embodiments, the adhesive layer is in direct contact with the water-absorbing layer and the polymer layer. As used herein, the term "adjacent" means that items such as layers of a film are close to each other, with or without intermediate materials, such as an adhesive layer. As used herein, the terms "directly adjacent", "directly connected" or "directly in contact" mean that the items are in contact with each other without intermediate materials. In some embodiments, the polymer layer is attached to the water-absorbing layer as a whole. As used herein, the term "integral" means, for example, less than or equal to 1% or less than or equal to 0.5% of the polymer layer is not attached to the water-absorbing layer. In some embodiments, the adhesive layer is patterned, which will be discussed in further detail below.

[0035] In some embodiments, a portion of the polymer layer is attached to the water-absorbing layer. As described herein, "a portion of the polymer layer is attached to the water-absorbing layer" means that the polymer layer remains at least partially attached to the water-absorbing layer, so that the polymer layer remains undamaged and attached to the water-absorbing layer during the production / processing process. In other words, the polymer layer may be partially attached to the water-absorbing layer or completely attached to the water-absorbing layer. In addition, in some embodiments, the polymer layer is coextensive with the water-absorbing layer. As described herein, "coextensive" means that one or more layers may occupy the same area.

[0036] As used herein, the term "patterning" means that the layer (e.g., adhesive layer) is discontinuous relative to the multilayer packaging film. In other words, the layer (e.g., adhesive layer) only covers a portion of the region of the multilayer packaging film. In certain embodiments, the patterned layer can define any suitable figure, graphic and / or text terms and / or define a pattern with any suitable shape, including but not limited to dot, point, line, crosshatch, diamond or checkerboard. The pattern of the adhesive can be seen or not seen by the polymer film through the polymer film. The pattern of the adhesive can be seen or not seen by the paper component through the paper component. The patterned adhesive can highlight the overall appearance of the packaged product. In certain embodiments, the adhesive layer is discontinuous relative to the polymer layer applied thereon. The adhesive layer can be applied on the surface of the polymer layer, which is greater than or equal to 5%, greater than or equal to 10%, or greater than or equal to 15%. The adhesive layer can be applied on the polymer layer, which is less than or equal to 30%, less than or equal to 25%, or less than or equal to 20%.

[0037] As used herein, the term "print layer" or "printed marking layer" refers to a layer or a series of sub-layers that have been printed on the film. The layer or sub-layer may include a pigmented material (i.e., a colored ink), a protective layer (i.e., a topcoat), and an ink-absorbing primer. The topcoat can protect the printed pigment layer and can improve the appearance of the surface of the film. Each of the one or more printed layers can be independently continuous or independently discontinuous (i.e., patterned) relative to the other layers of the film. Specifically, the printed layer may include one or more continuous sub-layers of white pigment prints and one or more patterned sub-layers including other colors, thereby producing a visible pattern of a multilayer packaging film. The printing of the printed layer can be completed by any known printing method, including but not limited to flexographic gravure printing, rotary gravure printing, gravure coating, and digital printing methods. The sub-layers within the printed layer may be applied by the same process or using different types of processes. In one or more embodiments, the printed layer does not contain or is substantially free of pigment materials. The printed layer may include a varnish and / or ink that is overprinted on the outer surface of the paper component. The varnish is intended to protect the outer surface of the paper component from environmental attack. The varnish can also be used to provide a glossy or matte appearance to the outer surface.

[0038] All layers and films described herein have two major surfaces opposite to each other and defined by the xy plane. As used herein, the term "outer layer" refers to one or more layers of a paper-based packaging film on any major surface of the film, i.e., a layer that is not between two other layers of the film. As described herein, the paper-based packaging film has an outer surface that becomes the exterior of the packaging using the film. When formed into a package, the outer surface of the film is exposed to the environment. In one or more embodiments, the water-absorbing layer defines the outer surface of the film, facing away from the packaged product, and is exposed to the environment. In one or more embodiments, the print layer defines the outer surface of the film, facing away from the packaged product, and is exposed to the environment. As described herein, the paper-based packaging film has an inner surface that becomes the interior of the packaging using the film. When formed into a package, the inner surface is exposed to the packaged product. In one or more embodiments, the polymer layer defines the inner surface of the film and is exposed to the packaged product.

[0039] One or more of the layers or films of the paper-based packaging film may be coextensive with each other. As used herein, "coextensive" means that one or more layers may occupy the same area.

[0040] Referring again to the paper component, the paper component is the outer layer of the paper-based packaging film, located at the outer surface of the paper-based packaging film. In some embodiments, the paper component includes additional components adjacent to or on the outer surface of the paper component, such as ink or topcoat. These additional components can cover a portion of the outer surface or the entire outer surface.

[0041] A "paper component" can be any type of paper that can be processed in a paper recycling (repulpability) process. As used herein, the term "paper component" can be described in terms of the amount of cellulose fibers in the paper component that can be recovered by a repulping process. For example, a paper component includes cellulose fibers or is essentially composed of cellulose fibers. As used in this context, "essentially composed of..." means that the total composition of the paper component includes greater than or equal to 95%, greater than or equal to 98%, greater than or equal to 99%, greater than or equal to 99.9% or 100% cellulose fibers. Therefore, in an embodiment where the total composition of the paper-based packaging film includes greater than or equal to 80% by weight, or greater than or equal to 90% by weight of the paper component, the total composition of the paper-based packaging film includes greater than or equal to 80% by weight, or greater than or equal to 90% by weight of cellulose fibers.

[0042] In some embodiments, the basis weight of the paper component is 15 g / m 2 Up to 100g / m 2 In the range of 20 g / m 2 Up to 60g / m 2range. Lower paper component weight is possible while maintaining easy recyclability because additional components are minimized. Examples of paper components that can be used in paper-based packaging films include, but are not limited to, kraft paper and bleached paper. The paper component can be coated (i.e., clay coated) or uncoated. Examples of commonly used paper in packaging that is acceptable in the paper-based packaging films described herein include machine-bleached kraft paper (MGBK), single-sided clay-coated paper (C1S), and double-sided clay-coated paper (C2S), but less commonly used paper that provides improved mechanical or barrier properties by using special fibers or additives can also be part of the paper-based packaging films described in this application. As described herein, the paper component does not include non-repulpable paper or paper that has been treated with wet strength treatment. Examples of non-repulpable paper that will not be available in the paper-based packaging films described herein include, but are not limited to, wet strength paper or wax paper. In the embodiment where the paper component is coated, the total composition of the paper component has cellulose fibers greater than or equal to 80%, or greater than or equal to 90%.

[0043] As used herein, the term "basis weight" is used to refer to the weight of a material present in a predetermined area of ​​a film or layer. Typically, the defined area is a square meter, but any area may be used. The area is defined in the length-width (i.e., xy direction) of the film or layer. A material of a given thickness (z direction) and density has a specific weight when covering a defined area (i.e., square meters). Basis weight is a common weight measurement for paper because the density of paper may vary greatly. In other words, it may be difficult to measure paper by thickness in the z direction. Materials applied in discontinuous layers (such as patterned materials) may also be defined by basis weight. In the case of a pattern, basis weight refers to the amount of material by weight present when covering a defined area. It is common in the film conversion industry to use basis weight to measure the weight of materials such as paper and patterned materials.

[0044] Figure 1 A process flow diagram of a method 100 for producing a multilayer packaging film according to one or more embodiments is illustrated. The method 100 includes: producing a polymer layer (operation 102); wearing the polymer layer (operation 104); and attaching the polymer layer to the water-absorbing layer through an adhesive lamination process to produce a multilayer packaging film (operation 106). In some embodiments, the adhesive lamination process (operation 106) is performed before wearing the polymer layer (operation 104). In some embodiments, the adhesive lamination process (operation 106) is performed after wearing the polymer layer (operation 104). In some embodiments, the method 100 optionally includes forming a printing layer on the outer surface of the water-absorbing layer (operation 108) and / or forming a package from the multilayer packaging film (operation 110).

[0045] The polymer layer may be produced at operation 102 by any suitable method known to those skilled in the art.

[0046] The adhesive lamination process at operation 106 includes laminating using one or more of a solvent-based adhesive, a water-based adhesive, or a solvent-free adhesive to form an adhesive layer. Unless otherwise expressly stated, the adhesive layer can have any suitable composition that provides a desired level of adhesion to one or more surfaces in contact with the adhesive. Solvent-based adhesives include polyurethane-based adhesives, such as two-component polyurethane adhesives, including but not limited to those having a solids content greater than 30% by weight. Specific examples of water-based adhesives include but are not limited to tak 9119X or Robond TM L280. Specific examples of solvent-free adhesives include, but are not limited to, MOR-FREE TM ELM 415A. Without wishing to be bound by theory, it is believed that the adhesive layer material has a negligible effect on the thickness of the film.

[0047] Embodiments of the present disclosure advantageously provide a paper-based multilayer packaging film including a water-sensitive adhesive layer. As used herein, the term "water-sensitive" means that when exposed to liquid water for a long time or immersed in liquid water, the adhesive layer loses its adhesive and / or cohesive properties, thereby enabling the paper component to be delaminated (i.e., separated) from the rest of the paper-based multilayer packaging film structure during the repulping process. Examples of materials that can be used in the adhesive layer between the water-absorbing layer and the polymer layer include, but are not limited to, latex / casein blends, starch, sugar derivatives, cellulose, amino resins, (poly)acrylates, polyvinyl alcohol (PVOH), polyvinyl acetate, polyacrylic acid, maleic acid-modified ethylene copolymers, methylcellulose, carboxymethylcellulose, carboxyl-functional polyesters, polyethylene succinate, polybutylene succinate, ionomers, or hydrophilic polyurethanes.

[0048] For example, using an adhesive lamination process instead of an extrusion lamination process advantageously provides the necessary bonding between the water-absorbing layer and the polymer layer by using less material, thereby making it easier to meet "recyclable" standards for high paper fiber content.

[0049] Thus, reducing the thickness of the polymer layer makes it possible to significantly increase the percentage of paper fiber content of the multilayer packaging film and thus allows meeting increasingly higher paper fiber content targets for recycling in paper recycling processes.

[0050] The transition from an extrusion coating process to a lamination process advantageously results in the use of thin bi-oriented polymer films, thereby providing an improvement in the mechanical strength of the final multilayer packaging film.

[0051] For example, the use of bi-oriented thin polymers would allow for the same natural barrier as an extrusion coated layer (without the randomly distributed micro-cuts) at a lower grammage and / or thickness.

[0052] Using an incomplete adhesive layer (e.g., a patterned adhesive layer) on the surface between the water-absorbing layer and the polymer layer, such as by using line or spot adhesive lamination, will also reduce the amount of adhesive. It is believed that reducing the amount of adhesive will achieve better recyclability of the multilayer packaging film because a reduced amount of paper fiber content will be attached to the thin polymer layer.

[0053] Figure 2 and Figure 3 Schematic cross-sectional views of various embodiments of multilayer packaging films 200 . Figure 2 and Figure 3 The multilayer packaging film 200 illustrated in FIG. 1 may be formed by the method 100 .

[0054] Figure 2 Illustrated is a multilayer packaging film 200 having a polymer layer 202 facing a food product (not illustrated) to be packaged, a water-absorbing layer (eg, a paper component) 206 , and an adhesive layer 204 attaching the polymer layer 202 to the water-absorbing layer 206 .

[0055] Figure 3 A multilayer packaging film 200 is illustrated having a polymer layer 202 facing a food product to be packaged (not illustrated), a water-absorbing layer (e.g., a paper component) 206, an adhesive layer 204 attaching the polymer layer 202 to the water-absorbing layer 206, and a print layer 208 on an outer surface of the water-absorbing layer 206.

[0056] Figure 2 and Figure 3 Each of the layers / films illustrated in the embodiment has a thickness measured in the z direction. As described herein, it may be difficult to measure adhesive layers and water-absorbing layers by thickness in the z direction. Therefore, weight measurements of materials such as paper and patterned materials (i.e., adhesive layers) may be expressed by basis weight. In some embodiments, the thickness 202A of the polymer layer 202 is in the range of 2 μm to 10 μm. In some embodiments, the thickness 202A of the polymer layer 202 is in the range of 2 μm to 8 μm, or in the range of 2 μm to 6 μm.

[0057] exist Figure 2 and Figure 3 In the exemplary embodiment of FIG. 2 , the adhesive layer 204 is in direct contact with the water-absorbing layer 206 and the polymer layer 202 .

[0058] As previously mentioned, the paper-based packaging film may also include ink located on the outer surface of the paper-based packaging film. The type of ink and the amount of ink may vary within the requirements to comply with local paper recycling guidelines.

[0059] Figure 4 Indicated Figure 2 and Figure 3204. A top view of various embodiments of a patterned adhesive layer of a paper-based multilayer packaging film is shown in FIG. The patterned adhesive layer may include adhesive layer 204. Figure 4 In the exemplary embodiment of , the patterned adhesive layer (eg, adhesive layer 204) defines a pattern having a checkerboard, adhesive area circles, non-adhesive area circles, and random shapes. The patterned adhesive layer may have other configurations, such as lines. Figure 4 The adhesive pattern shown in FIG. 1 has a regular pattern, but some embodiments may be less regular. For example, the lines of adhesive may be placed at or near the edges of the packaging film, leaving the center open. Alternatively, channels in a checkerboard pattern may appear at spaced intervals on the packaging film. Other configurations may be used.

[0060] Figure 5 Indicates including Figure 2 and Figure 3 Schematic cross-sectional view of a package 300 of a paper-based multilayer packaging film 200 shown in FIG. The package 300 has a top surface 302 and a bottom surface 304. The package 300 can be used to wrap around a food product (such as a cheese product). When formed into a package such as the package 300, the inner surface (not shown) is exposed to the packaged product. In one or more embodiments, the polymer layer 202 defines the inner surface (not shown) of the paper-based multilayer packaging film 200 and is exposed to the packaged product.

[0061] Since the package 300 is wrapped around the cheese product, the package 300 may include multiple folds. Figure 5 In the illustrated embodiment of FIG. 3 , package 300 includes a plurality of folds 310. The plurality of folds 310 may define any suitable shape.

[0062] For example, the wrapped package 300 with the cheese product therein may include a sticker (i.e., a label with a pressure-sensitive adhesive) on an outer surface (e.g., such as the top surface 302 and / or the bottom surface 304) of the package 300. In other embodiments, the wrapped package 300 with the cheese product therein may include a sticker on an outer surface (e.g., such as the top surface 302 and / or the bottom surface 304) of the package 300, which may then be placed in a carton.

[0063] For each of the inventive examples described below, the tensile properties of the multilayer packaging film, including tensile stress and percent elongation, were measured. The tensile properties provide an indication of the runnability of the multilayer packaging film on packaging equipment.

[0064] As used herein, the term "tensile stress" refers to the tensile load supported by a specimen at each moment of the test, expressed in units of N / 15 mm.

[0065] As used herein, the term "percent elongation" refers to the increase in the distance between marks produced by a tensile load and is expressed as a percentage of the distance between marks.

[0066] Each of the following documents related to tensile properties and procedures is incorporated herein by reference in its entirety. However, it should be noted that the following documents illustrate only typical embodiments of the present invention and documents belonging to examples of the present invention and therefore should not be considered as limiting the scope thereof, as the present invention may admit to other equally effective embodiments.

[0067] Relevant procedures: ST-083 / ST-118.

[0068] The method disclosed in ISO 527-3:2018, entitled "Plastics — Determination of tensile properties — Part 3: Test conditions for films and sheets." (formerly NF T 54-102, which has been cancelled).

[0069] Description of the MTS CRITERION 41 device.

[0070] Material:

[0071] 15mm wide cutting template (cutter or tool with blade).

[0072] If using tools with blades, wear protective gloves.

[0073] Automatic force measurement equipment: a calibrated dynamometer connected to a computer controlled TW Elite software.

[0074] Conditioning of samples: The measurements are preferably carried out in an air-conditioned room after conditioning for a minimum of 1 hour at 23 ± 2°C and 50 to 60% relative humidity (RH).

[0075] Operation Mode:

[0076] 1. In the case of a "composite" or "laminate", the material must be polymerized for 48 to 72 hours before testing. To accelerate polymerization, the material can be placed in an oven at 40°C for 24 hours.

[0077] 2. Cut three specimens at least 170 mm long and 15 mm wide in the direction of travel of the support and, if necessary, at least three more specimens in the transverse direction.

[0078] 3. Check whether the cut of the test specimen is clean and without roughness (Hint: To facilitate cutting of plastic sheets with a cutting machine, place the film between two sheets of paper).

[0079] 4. For plastic films or composites including plastic films, set the gap between the jaws of the dynamometer to 120 mm.

[0080] 5. Insert the specimen between the jaws, stretch the specimen slightly, and tighten the jaws sufficiently to prevent the support from slipping.

[0081] 6. Use a felt-tip pen to mark the specimen to be measured flush with each jaw so that any slippage of the support can be observed.

[0082] 7. Start measuring at a speed of 100 mm / min. The measurement ends when a fracture occurs in the material.

[0083] If the material breaks flush with the jaws, the measurement result is not taken into account.

[0084] In some embodiments, the paper-based packaging film (i.e., the starting composite or laminate) can be used in a repulping process. As further described below, the repulping process removes the paper component from the starting composite or laminate. The repulped paper content can be measured as a percentage of recycled cellulose fibers. The following procedure is used to determine the amount of cellulose fibers recovered after the repulping process. In some embodiments, and for each of the following inventive examples, a test method for separating paper from an extruded film or a film laminated with glue for the purpose of recycling materials is performed.

[0085] The test involves soaking the starting composite or laminate in a beaker of hot water and mixing it to separate the paper from the film and measure the amount of pulp recovered. In general, the equipment used includes:

[0086] -5x 5cm cutting templates

[0087] - Graduated beaker that can hold 500ml of water

[0088] - Heating plate pre-set to 45°C

[0089] - Propeller stirrer with adjustable speed

[0090] - Thermometer for controlling water temperature

[0091] -Precision scales

[0092] - Oven set at 70°C

[0093] Generally speaking, methods used to measure the amount of recycled paper content include:

[0094] 1. Turn on the hot plate.

[0095] 2. Cut ten 5*5cm samples from the approximately 1m sample.

[0096] 3. Weigh ten samples (P1).

[0097] 4. Fill the beaker with 500 ml of water at 45°C + / - 2°C.

[0098] 5. Place the filled beaker on the pre-set hot plate.

[0099] 6. Use a thermometer to measure the temperature of the water regularly.

[0100] 7. Introduce a rotating support with the propeller closest to the bottom of the beaker.

[0101] 8. Place the sample in water in a beaker.

[0102] 9. Start the agitator by adjusting the agitator (see Photo 2) so that its speed reaches 1100 rpm.

[0103] 10. Allow it to run for 15 minutes, checking the water temperature periodically.

[0104] 11. At the end of the measurement, turn off the hot plate and remove the stirrer.

[0105] 12. Remove the beaker and take out ten pieces of plastic film, place them on paper towels to drain, and place them between two paper towels in an oven set at 70°C to dry for 24 hours.

[0106] 13. Allow the ten plastic films to recondition at room temperature for at least 24 hours and weigh the ten films (P2).

[0107] The multilayer packaging film may have a moisture vapor transmission rate optimized for the product to be packaged therein. The moisture vapor transmission rate may be measured using a dynamic test protocol such as ASTM F1249. In some embodiments, the multilayer packaging film has a moisture vapor transmission rate of less than or equal to 1,200 g / m at 38°C and 90% RH according to ASTM F1249. 2 / day, less than or equal to 1,000g / m 2 / day, less than or equal to 800g / m 2 / day or less than or equal to 600g / m 2 In some embodiments, the multilayer packaging film has a water vapor transmission rate greater than or equal to 50 g / m2 at 38°C and 90% RH according to ASTM F1249. 2 / day, higher than or equal to 100g / m 2 / day, higher than or equal to 200g / m 2 / day or higher than or equal to 300g / m 2 For example, the water vapor transmission rate of a multilayer packaging film can be between 100 and 800 g / m 2 / day, 50 to 600 g / m 2 / day or 300 to 1,200g / m 2 / day range.

[0108] Alternatively, the moisture vapor transmission rate of the multilayer packaging film can be measured using a static test protocol such as ASTM E398. In some embodiments, the multilayer packaging film has a moisture vapor transmission rate of less than or equal to 200 g / m 2 / day, less than or equal to 190g / m 2 / day, less than or equal to 180g / m 2 / day or less than or equal to 170g / m 2 In some embodiments, the multilayer packaging film has a water vapor transmission rate greater than or equal to 10 g / m 2 / day, higher than or equal to 12g / m 2 / day, higher than or equal to 14g / m 2 / day or higher than or equal to 16g / m 2 For example, the water vapor permeability of a multilayer packaging film can be between 10 and 200 g / m 2 / day, 10 to 180 g / m 2 / day or 16 to 190g / m 2 / day range.

[0109] In some embodiments, the multilayer packaging film has an air permeability in the range of 0.1 mL / min Bendtsen to 200 mL / min Bendtsen, including all ranges and subranges therebetween, measured using the method disclosed in International Standard ISO 5636-3. A summary of the inventive examples and measured properties can be found in Tables 1-2.

[0110] The present disclosure will now be described with reference to the following examples of the invention.

[0111] Examples

[0112] Inventive Examples 1-7 are examples based on paper-based packaging films having one or more layers / films as described above. The paper-based packaging films in Inventive Examples 1-7 have been treated so that different levels of micro-cuts are applied in each of Inventive Examples 1-7, including multiple perforations extending through the thickness of the polymer layer and / or multiple abrasions with a length less than the thickness of the polymer layer. Therefore, the general structure of the paper-based packaging film is described below.

[0113] By using a dry basis weight of 2.4 g / m 2 The water-based adhesive material will be 40g / m 2 The paper assembly of 100% polypropylene (OPP) was laminated to an 8 μm oriented polypropylene (OPP) film to produce Inventive Example 1. An adhesive was applied to the polymer film with the smooth side of the paper facing the adhesive.

[0114] By using a dry basis weight of 2.4 g / m 2The water-based adhesive material will be 40g / m 2 The paper assembly of 100%> was laminated to an 8 μm oriented polypropylene (OPP) film to produce Inventive Example 2. An adhesive was applied to the rough side of the paper.

[0115] By using a dry basis weight of 2.4 g / m 2 The water-based adhesive material will be 40g / m 2 The paper assembly of 100% polypropylene (OPP) was laminated to an 8 μm oriented polypropylene (OPP) film to produce Inventive Example 3. An adhesive was applied to the smooth side of the paper.

[0116] By using a dry basis weight of 2.4 g / m 2 The water-based adhesive material will be 40g / m 2 The paper assembly of 100% polypropylene (OPP) was laminated to an 8 μm oriented polypropylene (OPP) film to produce Inventive Example 4. An adhesive was applied to the smooth side of the paper.

[0117] By using a dry basis weight of 2.4 g / m 2 The water-based adhesive material will be 40g / m 2 The paper assembly of 100% polypropylene (OPP) was laminated to an 8 μm oriented polypropylene (OPP) film to produce Inventive Example 5. An adhesive was applied to the smooth side of the paper.

[0118] By using a dry basis weight of 2.4 g / m 2 The water-based adhesive material will be 40g / m 2 The paper assembly of 100%> was laminated to an 8 μm oriented polypropylene (OPP) film to produce Inventive Example 6. An adhesive was applied to the smooth side of the paper.

[0119] By using a dry basis weight of 2.4 g / m 2 The water-based adhesive material will be 40g / m 2 The paper assembly of 100% polypropylene (OPP) was laminated to an 8 μm oriented polypropylene (OPP) film to produce Inventive Example 7. An adhesive was applied to the polymer film with the rough side of the paper facing the adhesive.

[0120] Embodiments of the present disclosure advantageously provide paper-based packaging films having high paper content. In Table 1, the different paper contents of each of the inventive examples are shown. Table 1 shows that for each of the inventive examples, the predetermined minimum target of 80% paper content by weight recovered during the repulping process was achieved.

[0121] In each of the examples of the present invention, the air permeability of the multilayer packaging film was measured using an L&W air permeability meter. The L&W air permeability meter measures the air permeability of the sample according to the standard defined in SCAN-P 26:78. According to SCAN-P26:78, the sample is held between the upper measuring head and the lower measuring head at a surface pressure of about 1 MPa. The nominal gauge pressure in the instrument is 20 kPa, and the measuring surface is 50 cm2 The pressure difference between the two faces of the sample is measured simultaneously with the air flow. A high-precision detector records the measured air flow.

[0122] According to SCAN-P 26:78, air permeability is defined as the average value of the airflow through the sample divided by the pressure difference between the measuring surface and the two sides of the paper. Using SI units, we obtain the following formula "m 3 / s / (m 2 xPa)" or in simplified form "μm / Pa s", which is a common symbol for permeability. Instruments, such as the L&W air permeability meter, include a flow detector with a measuring range of 0 to 5000 ml / min. Taking into account the actual air pressure at the measuring head and the actual air pressure of the ambient air, the measuring range is recalculated as follows: This allows the following approximate measurement range to be obtained through the derivative:

[0123] 2-40,000 Gurley seconds for a measurement volume of 100 ml.

[0124] At a measurement pressure of 1.47 kPa and for 10 cm 2 Measuring area, 0.3-8,800ml / min Bendtsen

[0125] For a diameter of 0.75, i.e. 285 mm 2 Measuring surface, 2-1,400SU

[0126] The recorded values ​​and calculations shown in Table 1 are based on the following formula:

[0127] S=166.7X u / (5Q X Lip)

[0128] where S is the air permeability in μm / Pa s, the flow rate in ml / min and Δp is the pressure difference between the two faces of the sample, i.e. the pressure at the level of the measuring head minus the pressure of the ambient air.

[0129] Table 1: Summary of paper content and air permeability properties of inventive examples

[0130]

[0131]

[0132] Table 2: Summary of bond strength and elongation properties of inventive examples

[0133]

[0134] Although the disclosure herein has been described with reference to specific embodiments and examples of the invention, it should be understood that these embodiments and examples of the invention are merely illustrative of the principles and applications of the disclosure.

[0135] Example:

[0136] Embodiment 1: A multilayer packaging film comprising: a polymer layer; a water-absorbing layer, wherein the water-absorbing layer comprises a basis weight of 15 g / m 2 Up to 100g / m 2 and an adhesive layer attaching the polymer layer to the water-absorbing layer, the adhesive layer having a relative humidity of 0.1 g / m 2 Up to 6g / m 2 The multilayer packaging film has a dry basis weight in the range of 500 Å to 200 Å, wherein the polymer layer has a plurality of micro-cuts, and the multilayer packaging film has an air permeability in the range of 0.1 mL / min Bendtsen to 200 mL / min Bendtsen as measured using the method disclosed in International Standard ISO 5636-3.

[0137] Embodiment 2: A multilayer packaging film comprising: a polymer layer; a water-absorbing layer, wherein the water-absorbing layer comprises a basis weight of 15 g / m 2 Up to 100g / m 2 and an adhesive layer attaching the polymer layer to the water-absorbing layer, wherein the polymer layer has a thickness in the range of 2 μm to 10 μm, a plurality of micro-cuts, and the multilayer packaging film has an air permeability in the range of 0.1 mL / min Bendtsen to 200 mL / min Bendtsen as measured using the method disclosed in International Standard ISO 5636-3.

[0138] Embodiment 3: The multilayer packaging film of any preceding embodiment, wherein the polymer layer comprises one or more of an oriented polyethylene (OPE) film, an oriented polypropylene (OPP) film, an oriented polyester-based polymer film, or a compostable polymer film.

[0139] Embodiment 4: The multilayer packaging film of Embodiment 3, wherein the polymer layer is a biaxially oriented polypropylene (BOPP) film.

[0140] Embodiment 5: The multilayer packaging film of any preceding embodiment, wherein the adhesive layer is in direct contact with the water absorbing layer and the polymer layer.

[0141] Embodiment 6: The multilayer packaging film of any preceding embodiment, wherein the adhesive layer is patterned.

[0142] Embodiment 7: The multilayer packaging film of any preceding embodiment, wherein the water-absorbing layer has a water absorption capacity of 0.01 g / m 2 Up to 30g / m 2 Water absorption within the range of .

[0143] Embodiment 8: The multilayer packaging film of any of the preceding embodiments, wherein the basis weight of the paper component is 20 g / m 2 Up to 60g / m 2 within the range.

[0144] Embodiment 9: The multilayer packaging film of any preceding embodiment, wherein the plurality of micro-cuts are randomly distributed.

[0145] Embodiment 10: The multilayer packaging film of any preceding embodiment, wherein the plurality of micro-cuts comprises a plurality of perforations extending through the thickness of the polymer layer and a plurality of abrasions having a length less than the thickness of the polymer layer.

[0146] Embodiment 11: The multilayer packaging film of Embodiment 10, wherein the plurality of abrasions are randomly distributed.

[0147] Embodiment 12: The multilayer packaging film of any preceding embodiment, wherein the total composition of the multilayer packaging film comprises greater than or equal to 80 weight percent of the paper component.

[0148] Embodiment 13: The multilayer packaging film of Embodiment 12, wherein the total composition of the multilayer packaging film comprises greater than or equal to 90 weight percent of the paper component.

[0149] Embodiment 14: The multilayer packaging film of any preceding embodiment, wherein the multilayer packaging film is wrapped around a food product.

[0150] Embodiment 15: The multilayer packaging film of Embodiment 14, wherein the food product is a cheese product.

[0151] Embodiment 16: The multilayer packaging film of any preceding embodiment, further comprising a printing layer on an outer surface of the water-absorbing layer, the printing layer facing away from the food product to be packaged.

[0152] Example 17: A method for producing a multilayer packaging film, the method comprising: producing a polymer layer; abrading the polymer layer; and attaching the polymer layer to a water-absorbing layer by an adhesive lamination process to produce the multilayer packaging film, wherein the polymer layer has a plurality of micro-cuts, and the multilayer packaging film has an air permeability in the range of 0.1 mL / min Bendtsen to 200 mL / min Bendtsen measured using the method disclosed in International Standard ISO 5636-3, and the water-absorbing layer comprises a paper component.

[0153] Embodiment 18: The method of Embodiment 17, wherein the adhesive lamination process is performed before abrading the polymer layer.

[0154] Embodiment 19: The method of Embodiment 17, wherein the adhesive lamination process is performed after abrading the polymer layer.

[0155] Embodiment 20: The method of any one of Embodiments 18-19, further comprising forming a printing layer on the outer surface of the water-absorbing layer, the printing layer facing away from the food product to be packaged.

[0156] Embodiment 21: The method of any of Embodiments 18-20, further comprising forming a package by wrapping the multilayer packaging film around the food product and adhering the polymer layer to the outer surface of the water-absorbing layer.

[0157] Embodiment 22: A multilayer packaging film comprising: a polymer layer having a thickness in the range of 2 μm to 10 μm, the polymer layer facing the cheese product to be packaged; and a base weight of 15 g / m 2 Up to 100g / m 2 A water-absorbing layer of a paper component in the range of 0.1 g / m 2 , the water-absorbing layer facing the cheese product to be packaged; and an adhesive layer attaching the polymer layer to the water-absorbing layer, the adhesive layer having a water-absorbing layer of 0.1 g / m 2 2 Up to 6g / m 2 The multilayer packaging film has a dry basis weight in the range of 0.1 mL / min Bendtsen to 200 mL / min Bendtsen, wherein the polymer layer has a plurality of micro-cuts randomly distributed in the polymer layer, the air permeability of the multilayer packaging film is measured using the method disclosed in International Standard ISO 5636-3, and the total composition of the multilayer packaging film includes 80 wt% of the paper component.

Claims

1. A multi-layer packaging film, comprising: polymer layer; The water-absorbing layer comprises a water-absorbing layer having a basis weight of 15 g / m 2 Up to 100g / m 2 Paper components within the range; as well as The polymer layer is attached to the water-absorbing layer by an adhesive layer having a strength of 0.1 g / m 2 Up to 6g / m 2 Dry basis weight in the range of Wherein the polymer layer has a plurality of micro-cuts and the multilayer packaging film has an air permeability in the range of 0.1 mL / min Bendtsen to 200 mL / min Bendtsen measured using the method disclosed in International Standard ISO 5636-3.

2. A multi-layer packaging film, comprising: polymer layer; The water-absorbing layer comprises a water-absorbing layer having a basis weight of 15 g / m 2 Up to 100g / m 2 Paper components within the range; as well as an adhesive layer attaching the polymer layer to the water absorbing layer, wherein the polymer layer has a thickness in the range of 2 μm to 10 μm, a plurality of micro-cuts, and the multilayer packaging film has an air permeability in the range of 0.1 mL / min Bendtsen to 200 mL / min Bendtsen measured using the method disclosed in International Standard ISO 5636-3.

3. The multilayer packaging film of claim 1, wherein the polymer layer comprises one or more of an oriented polyethylene (OPE) film, an oriented polypropylene (OPP) film, an oriented polyester-based polymer film, or a compostable polymer film.

4. The multilayer packaging film of claim 3, wherein the polymer layer is a biaxially oriented polypropylene (BOPP) film.

5. The multilayer packaging film of claim 1, wherein the adhesive layer is in direct contact with the water absorbing layer and the polymer layer. The multilayer packaging film of claim 1 , wherein the adhesive layer is patterned.

7. The multilayer packaging film of claim 1, wherein the water absorbing layer has a water absorption capacity of 0.01 g / m 2 Up to 30g / m 2 Water absorption within the range of .

8. The multilayer packaging film according to claim 1, wherein the basis weight of the paper component is 20 g / m 2 Up to 60g / m 2 within the range.

9. The multilayer packaging film of claim 1, wherein the plurality of micro-cuts are randomly distributed.

10. The multilayer packaging film of claim 1, wherein the plurality of micro-cuts include a plurality of perforations extending through the thickness of the polymer layer and a plurality of abrasions having a length less than the thickness of the polymer layer. The multilayer packaging film of claim 10 , wherein the plurality of abrasions are randomly distributed.

12. The multilayer packaging film of claim 1, wherein the total composition of the multilayer packaging film comprises greater than or equal to 80% by weight of the paper component.

13. The multilayer packaging film according to claim 12, wherein the total composition of the multilayer packaging film comprises greater than or equal to 90% by weight of the paper component.

14. The multilayer packaging film of claim 1, wherein the multilayer packaging film is wrapped around a food product.

15. The multilayer packaging film of claim 14, wherein the food product is a cheese product.

16. The multilayer packaging film of claim 1, further comprising a printing layer on an outer surface of the water-absorbing layer, the printing layer facing away from the food product to be packaged.

17. A method for producing a multilayer packaging film, the method comprising: producing a polymer layer; abrading the polymer layer; as well as attaching the polymer layer to the water-absorbing layer by an adhesive lamination process to produce the multilayer packaging film, The polymer layer has a plurality of micro-cuts, the multilayer packaging film has an air permeability in the range of 0.1 mL / min Bendtsen to 200 mL / min Bendtsen measured using the method disclosed in International Standard ISO 5636-3, and the water-absorbing layer comprises a paper component.

18. The method of claim 17, wherein the adhesive lamination process is performed prior to abrading the polymer layer.

19. The method of claim 17, wherein the adhesive lamination process is performed after abrading the polymer layer.

20. The method according to any one of claims 18-19, further comprising forming a printing layer on an outer surface of the water-absorbing layer, the printing layer facing away from the food product to be packaged.

21. The method of claim 18, further comprising forming a package by wrapping the multilayer packaging film around the food product and adhering the polymer layer to the outer surface of the water-absorbing layer.

22. A multi-layer packaging film, comprising: a polymer layer having a thickness in the range of 2 μm to 10 μm, said polymer layer facing the cheese product to be packaged; Including basis weight of 15g / m 2 Up to 100g / m 2 A water-absorbing layer of a paper component within the range of , the water-absorbing layer facing away from the cheese product to be packaged; as well as The polymer layer is attached to the water-absorbing layer by an adhesive layer having a strength of 0.1 g / m 2 Up to 6g / m 2 Dry basis weight in the range of The polymer layer has a plurality of micro-cuts randomly distributed in the polymer layer, the air permeability of the multilayer packaging film is in the range of 0.1 mL / min Bendtsen to 200 mL / min Bendtsen measured using the method disclosed in the international standard ISO5636-3, and the total composition of the multilayer packaging film includes 80 wt% of the paper component.

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