Polyolefinic packaging film

Abstract

The invention relates to a polyolefinic packaging film (1) for fat-containing food with at least one blocking layer (3), a functional layer (5) and a filled layer (2, 4, 6). The packaging film (1) is stretched to form a number of cavities, to adjust the total density of the packaging film (1), for a recycling process, to a value lower than 0.99 g / cm3.

Description

[0001] Polyolefin packaging film

[0002] Description

[0003] The invention relates to a polyolefinic packaging film for fatty foods with at least one blocking layer, one functional layer and one filled layer.

[0004] The classic packaging materials for food, especially for butter and cheese, are based either on satin paper or mostly on an aluminum composite film that is wax-coated on the butter side and has real parchment.

[0005] These packaging materials must meet a number of requirements, such as good appearance, printability, and impermeability to grease and light, as well as a certain degree of oxygen and water vapor permeability. Furthermore, the packaged food should not be affected by the packaging material itself during long storage periods. Finally, the packaging material must have high mechanical strength combined with good foldability.

[0006] EP 0 445 565 A2 describes a packaging material for solid, fatty goods, such as butter. The packaging material consists of an aluminum foil coated with a grease-resistant and grease-repellent protective coating on one side and a glassine layer laminated with an ethylene copolymer on the other side.

[0007] EP 2 314 450 A1 discloses a packaging film for butter and cheese, consisting of a laminate provided on one outer side with a coated aluminum foil. The aluminum foil has a thickness of 5-10 μm and is laminated with a paper-like HDPE film with a thickness of 20-50 μm. The packaging film retains sharp and permanent folds after folding, for example, by closing a conventional butter package.

[0008] DE 10 2010 053 115 A1 describes a package consisting of paper, film, tin foil or other formable, film-like packaging material, which completely packages pasty goods on the reverse side by initially folding them into a tube and then folding the end faces.

[0009] Aluminum-based food packaging is difficult to recycle because it is not pure aluminum, but rather a combination of many different materials that cannot be completely separated. Furthermore, aluminum loses quality and purity with each recycling step and requires large amounts of energy to recycle.

[0010] Filled polyolefin packaging films, especially polyethylene-based films, are a more environmentally friendly alternative to conventional packaging films, offering effective food protection and good printability for an attractive appearance. They exhibit a paper-like appearance and a pleasant feel.

[0011] These packaging films are made from recyclable polyolefins to which natural minerals are added. With up to or over 50% mineral content, the packaging films provide an effective barrier against light, oxygen, and water vapor, and are also grease-resistant. Furthermore, they exhibit significantly improved tear and fold resistance compared to more complex laminate solutions such as PE / paper.

[0012] Pure polyolefin waste products based on polyethylene and / or polypropylene can be directly remelted into new products or processed into regranulate. This recycled plastic is increasingly becoming a technically and economically viable alternative to virgin materials, thus saving fossil raw materials.

[0013] However, the separation of valuable plastic waste in the sink-float recycling process has proven problematic. The addition of water is intended to make the lightweight polyolefins float and be skimmed off. By using mineral fillers to reduce the proportion of fossil raw materials and achieve the desired mechanical properties and printability, the filled polyolefin packaging films float due to their density of more than 1.00 g / cm³. 3 no longer or not well.

[0014] Mechanical recyclability is currently defined as requiring polyolefin products to be material-specifically recyclable and capable of being sorted using state-of-the-art processes to be considered "recyclable." Mineral-filled polyolefin packaging films cannot therefore be recycled as desired. However, many consumers of fatty foods expect their packaging films to be recycled. There are now also legal frameworks that stipulate a minimum level of packaging recycling.

[0015] The object of the invention is to provide a polyolefin-based packaging film for fatty foods that is optimized for the sink-float process within a recycling process. The packaging film should have all the advantages of known polyolefin films for fatty foods. The food packaging should be grease-proof and light-proof, easy to fold, have excellent mechanical properties, and be advantageously printable. This object is achieved according to the invention by a polyolefin packaging film for fatty foods, a method, and a use according to the independent main claims. Preferred variants can be found in the dependent claims, the description, the exemplary embodiment, and the drawings.

[0016] According to the invention, the packaging film is stretched to produce a proportion of cavities to adjust the total density of the packaging film for a recycling process to a value of less than 0.99 g / cm 3 .

[0017] A cavity, or hollow space, is abstractly defined as an empty or gas-filled space within something solid. The space is thus surrounded by a solid boundary that separates it from the outside. In the case of a polyolefin film, the space is separated from the outside by a polymer material.

[0018] The cavities do not have to be completely closed and can, for example, be interconnected.

[0019] Preferably, a cavity and / or a plurality of cavities and / or all cavities of the film or individual layers of the film can be designed in the form of vacuoles.

[0020] Preferably, the volume fraction of the cavities in the or in each filled layer is more than 15%, preferably more than 25%, in particular more than 30% and / or less than 60%, preferably less than 50%, in particular less than 45%. This results in a film which, despite a high mineral content, has a total density of less than 0.99 g / cm 3 and can therefore float during a recycling process using the sink-float method. Ideally, the total density of the packaging film is less than 0.97 g / cm 3 , preferably less than 0.95 g / cm 3 , in particular less than 0.93 g / cm 3 and / or more than 0.70 g / cm 3 , in particular more than 0.75 g / cm 3 , in particular more than 0.80 g / cm 3 This significantly increases the speed of floating in the sink-float process, thus optimizing the economic efficiency of the recycling process.

[0021] To create cavities or hollow spaces, the packaging film is preferably stretched monoaxially in the machine direction by a factor of more than 2.0, preferably by a factor of more than 3.0, in particular by a factor of more than 4.0, and / or by a factor of less than 7.0, preferably by a factor of less than 6.5, in particular by a factor of less than 6.0. The fillers cause the formation of cavities in the filled layers during stretching of the packaging film.

[0022] Hard and inorganic fillers such as calcium carbonate (CaCO3) are particularly suitable as fillers for the filled layers of the packaging film.

[0023] In addition to or as an alternative to CaCO3, a metal oxide component can be used as a filler. Alkaline earth oxides are particularly advantageous as metal oxide components. Calcium oxide (CaO) has proven particularly advantageous, although the use of magnesium oxide is also conceivable.

[0024] Tale and / or calcium carbonate-magnesium carbonate have also proven particularly useful as fillers.

[0025] Preferably, the filler has a specific surface area of ​​less than 12 m 2 / g, preferably less than 10 m 2 / g, especially less than 8 m 2 / g on and / or more than 2 m 2 / g, preferably more than 3 m 2 / g, especially of more than 4 m 2 / g. A filler with such a specific surface is particularly well suited for creating cavities or vacuoles, which give the packaging film a total density of less than 0.99 g / cm3 and provide favorable opacity.

[0026] In a favorable variant of the invention, the average particle size of the filler in each filled layer is more than 0.5 pm, preferably more than 0.8 pm, in particular more than 1.2 pm and / or less than 8 pm, preferably less than 5 pm, in particular less than 3 pm. Filler particles with such an average particle size do not protrude from a filled layer.

[0027] The filler content can be determined using well-known measurement methods such as ashing. A sample with a known initial weight is heated to a temperature at which the polymer thermally decomposes but the filler does not. A temperature of 560 °C, for example, has proven effective for this purpose. The sample weight is then measured again. The polymer content per square meter can be calculated from the difference between the initial and final weight.

[0028] As an alternative to ashing, a TGA measurement is possible, in which the weight of a sample is continuously measured during heating. This test method can also clearly differentiate between polymer and filler and allows the polymer content of the film to be determined.

[0029] Ideally, the filler content in each filled layer of the packaging film is more than 20 wt.%, preferably more than 30 wt.%, in particular more than 40 wt.% and / or less than 80 wt.%, preferably less than 70 wt.%, in particular less than 60 wt. The filler content is such that stretching produces only microporous cavities that do not exhibit a significant network of interconnections.

[0030] Mineral fillers reduce the polymer content in films such as packaging film, making them particularly sustainable. This also reduces carbon dioxide emissions during the production of the packaging film. Recycled polyethylene is also suitable as a polymer component in packaging film, allowing for the creation of a particularly sustainable packaging film.

[0031] Opacity is the opposite of transparency. It is a measure of light impermeability or opacity and is usually expressed as a percentage. Specifically, the opacity of a completely opaque film is 100%, and a completely or fully transparent film has an opacity of 0%.

[0032] Ideally, the packaging film has an opacity according to DIN 53416 of more than 65%, preferably more than 70%, and especially more than 80%. This allows the film to be printed directly and eliminates the need for an opaque layer underneath the print, which must first be created or applied.

[0033] In a particularly advantageous variant of the invention, the proportion of titanium dioxide in the packaging film is less than 1 wt. %, preferably less than 0.5 wt. %, in particular less than 0.1 wt. %. This means that the packaging film is practically free of titanium dioxide and thus contains no supposedly carcinogenic substance. At the same time, by using at least one filled layer and by stretching monoaxially in the machine direction, an ideal opacity of the packaging film can be achieved, which is favorable for printing. The packaging film, which is practically free of titanium dioxide, therefore satisfies both the European chemicals regulation REACH and the amending regulation to the CLP regulation. The packaging film can therefore be described as free of harmful substances.

[0034] A packaging film for fatty foods, such as butter and cheese, should exhibit stable folding or crease resistance over time in storage, during sales and at the customer's premises, as measured according to ASTM D920-49.

[0035] Ideally, the packaging film has a dead fold of more than 35%, preferably more than 45%, especially more than 55% according to ASTM D920-49. Accordingly, the packaging film can advantageously maintain the wrapped shape throughout the period from packaging to consumption of the food.

[0036] In order to keep butter and cheese fresh for a long time and at the same time make the packaging film look attractive, the polyolefinic packaging film should have good grease resistance. The grease resistance of paper, coated paper or plastic films is tested using dyed palm kernel fat in accordance with DIN 53116. The sample is coated with the test grease on the test side and then placed on a glass plate and, if necessary, additional weights. After the exposure time has elapsed, the dot-shaped fat penetrations up to 1 mm in size that are visible to the naked eye on the indicator paper within the defined test area are evaluated. If only fat penetrations up to 1.0 mm are observed, the test is deemed to have been passed; for fat penetrations larger than 1.0 mm, the test must be carried out under milder test conditions.

[0037] Advantageously, the packaging film has a grease penetration according to DIN 53116 of less than 5, preferably less than 3, and in particular less than 1 per 100 mm x 100 mm. This makes the packaging film particularly suitable for packaging fatty foods. The film keeps the food fresh, prevents grease from seeping through, and looks attractive.

[0038] The determination of water vapor permeability for dry or moisture-sensitive goods is carried out according to DIN 53116 using a gravimetric measuring method. A test container filled with a desiccant is sealed with a sample of packaging film and exposed to a defined test climate. The amount of water permeating through the sample is determined by weighing. The water quantity can be in the range of 1 - 200 g / (m 2■ d) be detected. The detection limit also depends on the sample properties and the sample thickness.

[0039] Ideally, the packaging film has a water vapor transmission rate of less than 20 g / (m 2 ■ d), preferably less than 10 g / (m 2 d), in particular of less than 5 g / (m 2 ■ d) according to DIN 53122-1. The packaging film thus ensures minimal water vapor permeability and thus a particularly long storage time for fatty foods.

[0040] The gas permeability of plastic films is determined according to ISO 15105 using the differential pressure method. A sample made of packaging film separates two chambers, and the gas permeability through a plastic film is measured by the difference in partial pressure on both sides of the film. This method allows the gas permeability of a material to be determined quantitatively.

[0041] Advantageously, the packaging film has an oxygen transmission rate of less than 10,000 cm 3 / m 2 d bar, preferably less than 5,000 cm 3 / m 2 d bar, especially less than 2,000 cm 3 / m 2 d bar according to ISO 15105. The packaging film can thus significantly reduce the influence of oxygen on the shelf life of fatty foods.

[0042] In a particularly advantageous variant of the invention, the blocking layer comprises a black pigment, whereby the packaging film has a radiation or light transmittance according to DIN 10050-9 of less than 10%, preferably less than 7.5%, in particular less than 5%. The packaging film according to the invention provides excellent protection for a fatty foodstuff from radiation damage.

[0043] By incorporating the black pigment into the blocking layer, the blocking layer can also be interpreted as a barrier layer against light or radiation.

[0044] For example, the packaging film has a light transmittance of 1.5% according to DIN 10050-9.

[0045] In an alternative variant of the invention, the functional layer may additionally or exclusively comprise a black pigment, wherein the packaging film has a radiation or light transmittance according to DIN 10050-9 of less than 10%, preferably less than 7.5%, in particular less than 5%.

[0046] The flow behavior of polyolefins is described using the melt index (Ml) according to ISO 1133, typically at a temperature of 190 °C for polyethylene and 230 °C for polypropylene under a load of 2.16 or 5 kg. A higher melt index correlates with a lower average molecular weight of the polymer. At the same time, the higher the melt index of a polymer, the lower the melt viscosity, which is beneficial for good filler dispersion and high output from the extrusion line. On the other hand, polymers with a high molecular weight, i.e., a low melt index, are advantageous in terms of mechanical stability, especially tensile strength and toughness.

[0047] The functional layer of the packaging film is preferably made of at least 60 wt.% HDPE, the density of which is more than 0.940 g / cm 3 , preferably more than 0.950 g / cm 3and / or less than 0.965 g / cm 3 , preferably less than 0.960 g / cm 3 and / or whose melt flow index (at 190°C at 2.16 kg) according to ISO 1133 is more than 0.1 g / 10 min, preferably more than 0.2 g / 10 min, and / or less than 5.0 g / 10 min, preferably less than 3.0 g / 10 min. This results in a packaging film that is rigid while providing an excellent barrier against grease and excellent foldability.

[0048] For example, the functional layer of the packaging film is made of at least 65 wt.% HDPE, preferably of 70 wt.% HDPE, in particular of 80 wt.% HDPE.

[0049] In addition, the functional layer may, for example, comprise more than 15 wt.%, preferably more than 25 wt.%, in particular more than 35 wt.% of a polyolefin.

[0050] The blocking layer of the packaging film is preferably made of a metallocene LLDPE whose density is more than 0.86 g / cm 3 , preferably more than 0.88 g / cm 3 and / or less than 0.92 g / cm 3 , preferably less than 0.91 g / cm 3 and / or whose melt flow index (at 190 °C at 2.16 kg) ISO 1133 is more than 0.1 g / 10 min, preferably more than 0.2 g / 10 min and / or less than 5.0 g / 10 min, preferably less than 3.0 g / 10 min. The blocking layer advantageously provides radiation opacity and prevents the film from sticking until the desired welding, for example when laminating with another film or realized in the blocked version of the packaging film.

[0051] A frequently used method for printing packaging film is flexographic printing. This is a direct relief printing process, also known as a web-fed rotary printing process. The flexible printing plates, made of photopolymer or rubber, are used in combination with low-viscosity printing inks. The raised areas of the printing form carry the image. The advantages lie in the cost-effectiveness due to the utilization of a large printing width and high printing speed, as well as the availability of inexpensive printing inks. The printing tools essentially consist of photopolymer printing plates and / or laser-engraved elastomer sleeves. Large print runs can be produced cost-effectively with flexographic printing.

[0052] High opacity is crucial for a high-quality print image on a polyolefin film. To achieve this, titanium dioxide is typically added to the composition before film extrusion to achieve high opacity. In 2019, the European Commission decided, in an amending regulation to the CLP Regulation, to classify titanium dioxide powder, among other substances, as a suspected carcinogen. The use of titanium dioxide should therefore be reduced or, better yet, avoided.

[0053] In addition, polyolefin films should be particularly stiff for use in packaging films for fatty foods. However, the undesirable elasticity of the film causes problems with printability, as print sharpness can suffer and, at the same time, high printing ink consumption occurs to achieve the highest possible quality print image. In a particularly advantageous variant of the invention, a print is applied directly to a filled layer of the packaging film. The print can be implemented as a print motif. In the packaging film sector, the term print motif refers to the thematic design element of a print. If necessary, print motifs identifying the manufacturer can also be included in the scope of the print.

[0054] For example, the print can also be applied as a primer. This can advantageously improve the adhesion of subsequent prints.

[0055] Preferably, the print is applied to a filled layer of the packaging film using a flexographic printing process, whereby all common printing processes are in principle suitable for this purpose and are expressly included in the invention.

[0056] The proportion of fillers in the filled layers, combined with monoaxial stretching in the machine direction, results in a film that is particularly stiff in the xy direction, while also exhibiting elasticity in the z direction due to the fillers. This allows for better application of the printed image and improved adhesion, while using less ink, especially compared to printed papers. This results in a high-resolution and sharp print image.

[0057] In an alternative variant of the invention, the filled layers of the packaging film can each have different filler contents. As a result, different volume fractions of cavities are formed in the filled layers due to the different filler contents. Preferably, the outermost filled layer, on which a print is directly applied, would have a higher filler content and thus a higher opacity.

[0058] In an advantageous embodiment, the polyolefin film is used as packaging for butter and cheese. For this purpose, the thickness of the packaging film is less than 100 μm, preferably less than 85 μm, in particular less than 70 μm, and / or more than 20 μm, preferably more than 35 μm, in particular more than 50 μm.

[0059] Ideally, the packaging film has a flexural rigidity according to ISO 2493 of more than 100 mN / m, preferably more than 200 mN / m, and especially more than 300 mN / m. This makes the packaging film particularly dimensionally stable and rigid.

[0060] The tensile properties are determined according to DIN EN ISO 527. In the tensile test, a sample strip of a film is stretched at a constant speed specified in the test standard and the force F is recorded with the change in length AL of the measuring section Lo.

[0061] Advantageously, the packaging film has a tensile strength in the machine direction according to DIN EN ISO 527-3 of more than 30 MPa, preferably more than 60 MPa, in particular more than 100 MPa.

[0062] For example, the packaging film has a modulus of elasticity according to DIN EN ISO 527-3 in the machine direction and / or transverse to the machine direction of more than 500 MPa, preferably more than 800 MPa, in particular more than 1100 MPa, and / or less than 2000 MPa, preferably less than 1900 MPa, in particular less than 1800 MPa. In a particularly advantageous variant of the invention, the polyolefin on which the entire packaging film is based is a polyethylene. Polyethylene (PE) is a thermoplastic produced by chain polymerization of petrochemically produced ethene. Polyethylene is semi-crystalline and non-polar.

[0063] Ideally, the polyolefin is formed exclusively as polyethylene. This means that the food packaging meets the requirements of the European Union's Plastics Pact, is based on a monomaterial construction, and is recyclable.

[0064] According to the invention, the process for producing a packaging film comprises several steps. First, various compositions of the polymer components are prepared, which are then extruded into a film web with at least three layers. The polymer mixtures differ with regard to the filled layer and the unfilled functional layer as well as the blocking layer, with the polymer mixture of the filled layer containing a filler for creating cavities. Advantageously, the film web is stretched monoaxially in the machine direction, whereby the favorable properties with regard to the total density below 0.99 g / cm 3 , opacity and printability, and grease and gas impermeability of the packaging film can be achieved. The film web can then be printed directly.

[0065] The properties of the blocking layer also make this layer functional as a barrier layer, especially as a barrier against light or radiation.

[0066] Packaging film is produced by monoaxial stretching with machine direction orientation (MDO). The film is heated to a temperature slightly below its melting point and stretched in a specific orientation. Stretching can also be performed directly after extrusion, when the film web is still at a temperature slightly below its melting point.

[0067] Ideally, the extrusion is carried out as blow extrusion, which promotes the development of advantageous film characteristics, such as stiffness.

[0068] In an advantageous variant of the invention, the packaging film is stretched monoaxially in the machine direction by a factor of more than 2.0, preferably by a factor of more than 3.0, in particular by a factor of more than 4.0 and / or by a factor of less than 7.0, preferably by a factor of less than 6.5, in particular by a factor of less than 6.0. This gives the packaging film advantageous folding resistance and favorable opacity, and at the same time, the density of the packaging film has a value of less than 0.99 g / cm 3 .

[0069] The packaging film is preferably also based on a monomaterial construction of polyethylene. This allows the packaging film according to the invention to be used as a recyclable and single-variety printed packaging for fatty foods, which, despite its high mineral content, has a total density of less than 0.99 g / cm 3and can therefore float during a recycling process using the sink-and-float process. The packaging film meets the requirements of the European Union's Plastics Pact and is free of harmful substances according to the amending regulation to the CLP Regulation.

[0070] The packaging film according to the invention is significantly more sustainable and environmentally friendly than satin-finished paper and / or aluminum composite film. Furthermore, the packaging film is also recyclable. Compared to satin-finished paper or aluminum composite film, the production of packaging films also saves (environmental) costs due to lower energy consumption in the manufacturing process. The packaging film has a significantly lower carbon footprint than satin-finished paper or aluminum composite film.

[0071] In one application, the packaging film can also be laminated with other films to achieve, for example, grease resistance, opacity and flexural rigidity in a laminating laminate.

[0072] Further advantages and features of the invention will become apparent from the description of an embodiment with reference to drawings and from the drawings themselves.

[0073] This shows

[0074] Fig. 1 shows a schematic structure of the packaging film according to the invention,

[0075] Fig. 2 shows a schematic structure of the packaging film in a blocked embodiment.

[0076] Fig. 1 shows a schematic structure of the packaging film 1. A print 7 is arranged on the packaging film 1. The print 7 includes motifs depicting, for example, fatty foods. Furthermore, identifying and informative prints 7 are also conceivable. Furthermore, visual recognition and the imaging support of a brand image can also be incorporated into the print 7. In the embodiment shown in Fig. 1, the packaging film 1 has a five-layer structure. Layers 2, 4, and 6 are designed as mineral-filled PE layers, with the CaCO3 content being approximately 50% by weight.

[0077] The unfilled functional layer 5 is arranged between the filled layers 4 and 6. The unfilled functional layer 5 is made of 60 wt% HDPE and 40 wt% COC polyethylene.

[0078] The density of HDPE is 0.953 g / cm 3and its melt flow index (at 190 °C at 2.16 kg) according to ISO 1133 is 0.3 g / 10 min. The unfilled functional layer 5 realizes the tough, tear-resistant and rigid properties of the packaging film 1. In addition, the functional layer 5 prevents the penetration of grease.

[0079] Packaging film 1 has a thickness of 300 μm after blow extrusion. After monoaxial stretching by a factor of 5.0, the thickness of the packaging film is 60 μm.

[0080] The blocking layer 3 is made of a metallocene LLDPE, whose density is 0.902 g / cm 3 and whose melt flow index (at 190 °C at 2.16 kg) according to ISO 1133 is 1.0 g / 10 min. The blocking layer 3 provides the radiation resistance of the packaging film 1.

[0081] The embodiment of the packaging film 1 shown in Fig. 2 essentially corresponds to the embodiment in Fig. 1. In this embodiment, the packaging film 1 is blocked in a ten-layer structure consisting of two film webs 8 that are joined in a mirror-image manner at the blocking layer 3. The blocking layer 3 functions here to block two identical films. For this purpose, the filled layer 2 is swapped in order with the blocking layer 3 and is thus arranged between the blocking layer 3 and the filled layer 4. The packaging film is monoaxially stretched by a factor of 6.0 and has a thickness of 85 pm.

Claims

Patent claims 1 . Polyolefinic packaging film (1) for fatty foods with at least one blocking layer (3), one functional layer (5) and one filled layer (2, 4, 6), characterized in that the packaging film (1) is stretched to produce a proportion of cavities for adjusting the total density of the packaging film (1) for a recycling process to a value of less than 0.99 g / cm 3 .

2. Packaging film according to claim 1, characterized in that the total density of the packaging film (1) is less than 0.97 g / cm 3 , preferably less than 0.95 g / cm 3 , in particular less than 0.93 g / cm 3 and / or more than 0.70 g / cm 3 , in particular more than 0.75 g / cm 3 , in particular more than 0.80 g / cm 3 amounts.

3. Packaging film according to claim 1 or 2, characterized in that the volume fraction of the cavities in the filled layer (2, 4, 6) is more than 15%, preferably more than 25%, in particular more than 30% and / or less than 60%, preferably less than 50%, in particular less than 45%. Packaging film according to one of claims 1 to 3, characterized in that the packaging film (1) has a dead fold of more than 35%, preferably more than 45%, in particular more than 55% according to ASTM D920-49. Packaging film according to one of claims 1 to 4, characterized in that the packaging film (1) has a grease penetration according to DIN 53116 of less than 5, preferably less than 3, in particular less than 1 per 100 mm x 100 mm. Packaging film according to one of claims 1 to 5, characterized in that the packaging film (1) has an opacity according to DIN 53416 of more than 65%, preferably more than 70%, in particular more than 80%. Packaging film according to one of claims 1 to 6, characterized in that the proportion of titanium dioxide in the packaging film (1) is less than 1 wt.%, preferably less than 0.5 wt.%, in particular less than 0.1 wt.%. Packaging film according to one of claims 1 to 7, characterized in that the packaging film (1) has a water vapor permeability rate of less than 20 g / (m 2 ■ d), preferably less than 10 g / (m 2 ■ d), in particular of less than 5 g / (m 2 ■ d) according to DIN 53122-1. Packaging film according to one of claims 1 to 8, characterized in that the packaging film (1) has an oxygen permeability rate of less than 10,000 cm 3 / m 2 d bar, preferably less than 5,000 cm 3 / m 2 d bar, especially less than 2,000 cm 3 / m 2d bar according to ISO 15105. Packaging film according to one of claims 1 to 9, characterized in that the blocking layer (3) and / or the functional layer (5) comprises a black pigment, wherein the packaging film (1) has a light transmittance according to DIN 10050-9 of less than 10%, preferably less than 7.5%, in particular less than 5%.

11. Packaging film according to one of claims 1 to 10, characterized in that the functional layer (5) is formed from at least 60 wt.% HDPE, the density of which is more than 0.945 g / cm 3 , preferably more than 0.950 g / cm 3 and / or less than 0.965 g / cm 3 , preferably less than 0.960 g / cm 3and / or whose melt flow rate (at 190 °C at 2.16 kg) according to ISO 1133 is more than 0.1 g / 10 min, preferably more than 0.2 g / 10 min and / or less than 5.0 g / 10 min, preferably less than 3.0 g / 10 min.

12. Packaging film according to one of claims 1 to 11, characterized in that the blocking layer (3) comprises a metallocene LLDPE whose density is more than 0.86 g / cm 3 , preferably more than 0.88 g / cm 3 and / or less than 0.92 g / cm 3 , preferably less than 0.91 g / cm 3 and / or whose melt flow rate (at 190 °C at 2.16 kg) according to ISO 1133 is more than 0.1 g / 10 min, preferably more than 0.2 g / 10 min and / or less than 5.0 g / 10 min, preferably less than 3.0 g / 10 min. Packaging film according to one of claims 1 to 12, characterized in that the filled layer (2, 4, 6) comprises an inorganic carbonate as filler, wherein the filler has a specific surface area of ​​less than 10 m 2 / g, preferably less than 8 m 2 / g, especially of less than 6 m 2 / g and / or more than 2 m 2 / g, preferably more than 3 m 2 / g, especially of more than 4 m 2 / g. Packaging film according to one of claims 1 to 13, characterized in that the proportion of filler in the filled layer (2, 4, 6) is more than 20 wt. %, preferably more than 30 wt. %, in particular more than 40 wt. % and / or less than 80 wt. %, preferably less than 70 wt. % and in particular less than 60 wt. %. Packaging film according to one of claims 1 to 14, characterized in that the packaging film (1) is stretched monoaxially in the machine direction by a factor of more than 3.0, preferably by a factor of more than 3.5, in particular by a factor of more than 4.0 and / or by a factor of less than 7.0, preferably by a factor of less than 6.5, in particular by a factor of less than 6.

0.

16. Packaging film according to one of claims 1 to 15, characterized in that at least one print (7) is arranged directly on the filled layer (2, 6) of the packaging film (1).

17. Packaging film according to one of claims 1 to 16, characterized in that the packaging film (1) has a thickness of less than 100 pm, preferably less than 85 pm, in particular less than 70 pm and / or more than 20 pm, preferably more than 35 pm, in particular more than 50 pm.

18. Packaging film according to one of claims 1 to 17, characterized in that the packaging film (1) has a flexural rigidity according to ISO 2493 of more than 100 mN / m, preferably of more than 200 mN / m, in particular of more than 300 mN / m.

19. Packaging film according to one of claims 1 to 17, characterized in that the packaging film (1) has a tensile strength in the machine direction according to DIN EN ISO 527-3 of more than 30 MPa, preferably more than 60 MPa, in particular more than 100 MPa. Method for producing a packaging film (1) comprising the following steps: - Production of various compositions, - extrusion of the compositions to form a film web, - stretching the film web in the machine direction to form a Packaging film (1), - Printing the packaging film (1). Use of the packaging film (1) according to one of claims 1 to 19 as recyclable packaging for fatty foods.

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