Packaging comprising a biaxially oriented polyethylene film

Abstract

A packaging for storing frozen articles, preferably foodstuffs, which comprises a laminated film, wherein said laminated film comprises at least a first layer and a second layer, wherein: said first layer is a biaxially oriented polyethylene film layer; and said second layer is a second polyethylene film layer; wherein said packaging comprises ≥ 90.0% by weight of polyethylene, based on the total weight of the laminated film. This packaging exhibits desirably high impact strength at temperatures below 0 °C, for example at -25 °C, and presents a mono-material solution that allows for further appropriate processing of said packaging via recycling techniques.

Description

[0001] The present invention relates to a package comprising a biaxially oriented film.

[0002] In the field of packaging, there is a continuing need to reduce the amount of material used to manufacture a package. The benefits of such a reduction are obvious in that the package will have a lower weight, utilize fewer material resources, and will result in a reduced amount of waste after the end of its useful life.

[0003] In a wide variety of packaging applications, an entire package or part of a package can be made of a polymeric film. In particular, polyethylene materials are suitable and widely used materials in a wide variety of packages.

[0004] To reduce the weight of a polyethylene film, one option is to reduce the thickness of the film. However, such a reduction in the thickness of the film generally results in the deterioration of film properties, such as its mechanical properties.

[0005] One way to improve the mechanical properties of a thickness-reduced polyethylene film is to start with a film having a higher thickness and subject such a film to an orientation process at a temperature below the melting point of the polyethylene material. Thus, such orientation causes the film to be stretched, and thus the thickness of the film is reduced.

[0006] Such orientation is generally carried out via a biaxial orientation process, in which first a film is produced via cast film extrusion, and then after cooling to below the melting temperature, the film is subjected to tensile forces to cause orientation in the longitudinal direction (i.e., the direction in which the film is manufactured during the film extrusion process), and subsequently subjected to tensile forces in the transverse direction (i.e., the direction perpendicular to the longitudinal direction in the plane of the film).

[0007] Such biaxially oriented polyethylene films can have far superior film properties, such as mechanical properties, compared to polyethylene films having a similar thickness but produced via conventional film production processes, such as cast extrusion or blown film production, in which the film is not subjected to stretching at a temperature below the melting point of the film.

[0008] In the field of packaging, it is desirable for a package to meet certain properties to be suitably qualified for a given type of packaging application. In this regard, a particular property for certain applications is to maintain mechanical properties at reduced temperatures that the package can withstand, such as during use in deep-freezing applications (where the temperature typically reaches -30 °C). To be qualified for use under such conditions, the package needs to exhibit at least good puncture resistance, tear resistance, and good seal integrity in the case where a seal, such as a heat seal, is applied to the package at such low temperatures.

[0009] During the storage of frozen items, the items to be stored are typically provided in parts that can be used individually by the consumer. For example, for consumer goods such as food products, a part of the product is to be accommodated such that the consumer can access that part in a simple manner while ensuring that during the production, storage, and use of the accommodated part of the item, the item does not suffer from the detrimental conditions of the external environment to which the accommodated part of the item is subjected. That is, that part of the item is to be packaged in such a way that the package maintains a closed system until the item needs to be removed from the package.

[0010] A widely used way of packaging such items for storage under deep-freezing conditions is in the form of being accommodated in a sealed bag. Typically, such bags are produced from polymer film materials.

[0011] Another aspect contributing to the requirements for such packaging materials for frozen items concerns the recyclability of the materials used in the packaging. Given the ongoing desire to increase the proportion of packaging materials that can withstand the recycling process, in order to reduce waste and raw material consumption, it is necessary to produce packaging suitable for recycling. A specific way to contribute to this goal is to ensure that the polymer materials used in the packaging produced from polymer film materials belong to the same polymer type. In recycling technologies, film materials containing multiple polymer types are not suitable for a certain number of recycling methods. The more consistent the composition of the material stream for recycling, the more suitable such a stream is for recycling.

[0012] Therefore, it is desirable to ensure that the package contains a certain high proportion of polymer materials belonging to the same class of materials. Typically, it is desirable for the package to contain at least 90 wt%, or at least 95 wt%, or even at least 97 wt% of polymer materials of the same class. Such a package is typically referred to as a mono-material package.

[0013] Therefore, this poses a further requirement for the packaging solutions for frozen food materials, in that they are desired to contain at least 90 wt% of polymer materials belonging to the same class.

[0014] Another specific property for certain applications in this regard is to provide a certain amount of stiffness to the packaging film, which allows for certain packaging applications where the package needs to have such structural stiffness as to be able to withstand without external support, such as in the case of a pouch. Pouches typically contain liquid-flowing contents that can exhibit more or less viscous behavior, such as certain food products, including for example soups, sauces, dairy products, oils and fats, and certain detergents or health products, such as liquid soaps, shampoos, dishwashing liquids, laundry detergents, fabric softeners, etc., to name just a few.

[0015] In addition to the stiffness properties, in order to accommodate the above applications, the packaging film also needs to meet more material specifications. In particular, the film needs to provide sufficient barrier properties to ensure that the contents are not adversely affected by the environment and, conversely, that the contents of the package do not leak out of the package; the film needs to provide sufficient puncture resistance and impact resistance to ensure that during normal handling, there is no leakage of the packaging material. In addition, in some applications, it is desirable for the film to provide sufficient printability so that when providing markings in printing (usually provided in the packaging of consumer items), it can be completed at a desired high printing speed, desired high resolution, and color fastness.

[0016] In particular, since reducing weight is an ongoing trend in the packaging industry, it is desirable to meet the above specifications while providing a packaging material solution that has lower requirements in terms of the amount of material used compared to materials in the art.

[0017] Another aspect contributing to the requirements for such film materials for sachets relates to the recyclability of the materials used in the packaging. Given the ongoing desire to increase the proportion of packaging materials that can withstand the recycling process, in order to reduce waste and raw material consumption, it is necessary to produce packaging suitable for recycling. One specific way to achieve this goal is to ensure that the polymer materials used in the packaging produced from polymer film materials belong to the same type of polymer. In recycling technologies, film materials containing multiple polymer types are not suitable for a certain number of recycling methods. The more consistent the composition of the material stream for recycling, the more suitable this stream is for recycling.

[0018] Therefore, it is desirable to ensure that the packaging contains a certain high proportion of polymer materials belonging to the same type of material. Generally, it is desirable for the packaging to contain at least 90 wt%, or at least 95 wt%, or even at least 97 wt% of the same type of polymer material. Such packaging is commonly referred to as single-material packaging.

[0019] Therefore, this places further requirements on the sachet solutions in that they are expected to contain at least 90 wt% of the same type of polymer material.

[0020] Another application of the biaxially oriented polyethylene film is suitable for packaging fresh cheese products such as soft cheese products, especially those packaged with a certain amount of aqueous medium. Typical examples of such soft cheese products are mozzarella-type cheese, feta-type cheese, and halloumi cheese, to name just a few. The specific nature of such applications is to provide a certain amount of barrier properties so that the quality of the packaged item can be maintained without being adversely affected by chemical compounds that penetrate into the package from the surrounding environment in which the package is located during the shelf life. Additionally, conversely, the package must not allow chemical compounds that form part of the contents of the package to leak out of the package in an undesirable manner.

[0021] In addition, the film needs to provide sufficient puncture resistance and impact resistance to ensure that there is no leakage of the packaged material during normal handling. In addition, in certain applications, it is desirable for the film to provide sufficient printability so that when providing markings in printing (usually provided in the packaging of consumer-use items), it can be completed at a desired high printing speed, desired high resolution, and colorfastness.

[0022] In particular, since reducing weight is an ongoing trend in the packaging industry, it is desirable to meet the above specifications while providing a packaging material solution with lower requirements in terms of material usage compared to materials in the art.

[0023] Another aspect contributing to the requirements for such film materials for packaging relates to the recyclability of the materials used in packaging. Considering the continuous desire to increase the proportion of packaging materials that can withstand the recycling process, in order to reduce waste and raw material consumption, it is necessary to produce packaging suitable for recycling. A specific way to achieve this goal is to ensure that the polymer materials used in the packaging produced from polymer film materials belong to the same type of polymer. In recycling technologies, film materials containing multiple polymer types are not suitable for a certain number of recycling methods. The more consistent the composition of the material stream for recycling, the more suitable this material stream is for recycling.

[0024] Therefore, it is desirable to ensure that the packaging contains a certain high proportion of polymer materials belonging to the same type of material. Generally, it is desirable for the packaging to contain at least 90 wt%, or at least 95 wt%, or even at least 97 wt% of the same type of polymer material. Such packaging is usually referred to as mono-material packaging.

[0025] Therefore, this places further requirements on the packaging solutions for storing dairy products, in that they are desired to contain at least 90 wt% of the same type of polymer material.

[0026] The specific property for certain other applications in this regard is puncture resistance, as the sharp edges or components present in the item to be packaged can cause the packaging to be punctured. In particular, when the packaging involves removing air from the packaging to form a vacuum packaging, a certain puncture pressure is exerted on the packaging, and the packaging needs to be resistant to this pressure.

[0027] Typical examples of objects to be packaged that may contain certain sharp edges are seafood products, especially those involving shellfish, lobsters, crabs, and other similar products. In addition, meat products containing bones may also contain certain sharp edges. The materials used to package these products must have properties such that no perforation occurs during the packaging process or during the shelf life of the product. When such perforation occurs, the product will be exposed to the environment, making it more prone to degradation. This situation needs to be avoided, and thus the quality of the packaging materials needs to meet this requirement.

[0028] Typically, to achieve this, a particularly thick plastic laminating film material is used. However, this runs counter to the above-mentioned driving force in the packaging industry to reduce material consumption and packaging weight.

[0029] Accordingly, there is a need to provide a packaging for articles with sharp edges that, compared to the prior art, combines the stringent requirements of puncture resistance with a reduction in packaging weight.

[0030] Another aspect to be considered is that once the air is evacuated from the packaging, the packaging needs to be sealed. For example, such sealing can be accomplished by heat-sealing the packaging. To facilitate this, the inner layer of the packaging should have properties such that a strong seal can be applied, preferably at the lowest possible sealing temperature, since using a low sealing temperature avoids unnecessary exposure of the contents of the packaging to deteriorating conditions.

[0031] Another aspect contributing to the requirements for packaging materials for such articles with sharp edges relates to the recyclability of the materials used in the packaging. Given the ongoing desire to increase the proportion of packaging materials that can withstand the recycling process, in order to reduce waste and raw material consumption, it is necessary to produce packaging suitable for recycling. One specific way to achieve this goal is to ensure that the polymer materials used in packaging produced from polymer film materials belong to the same polymer type. In recycling technology, film materials containing multiple polymer types are not suitable for a number of recycling methods. The more consistent the composition of the material stream for recycling, the more suitable such a stream is for recycling.

[0032] Accordingly, it is desirable to ensure that the packaging contains a certain high proportion of polymer materials belonging to the same class of materials. Typically, it is desirable for the packaging to contain at least 90 wt%, or at least 95 wt%, or even at least 97 wt% of polymer materials of the same class. Such packaging is commonly referred to as mono-material packaging.

[0033] Accordingly, this places further requirements on the solutions for packaging articles with sharp edges, in that they are desired to contain at least 90 wt% of polymer materials belonging to the same class.

[0034] Another specific type of packaging to which polymer films and laminates can be applied is vacuum packaging. By vacuum packaging, the contents of the packaging are packaged in such a way that the amount of air present within the packaging is minimized, thereby avoiding deterioration of the packaging contents due to reaction with air, in particular with oxygen in the air. This is particularly relevant for ensuring a long shelf life for products that are prone to such deterioration or degradation, such as including certain foods.

[0035] Such vacuum packaging typically involves placing the item to be packaged in a container, such as a bag, evacuating the air from the package, and then applying a sealant to the bag to ensure that air does not enter the package. This sealant can be applied by heat sealing.

[0036] To provide the required properties suitable for such vacuum packaging applications, the polymeric film or laminate must have sufficient gas barrier properties, as well as puncture resistance and heat seal properties.

[0037] Typically, to achieve this, a particularly thick plastic laminate film material is used. However, this runs counter to the above-mentioned driving forces in the packaging industry to seek to reduce material consumption and reduce the weight of the packaging. To facilitate this, the inner layer of the packaging should have properties such that a strong seal can be applied, preferably at the lowest possible sealing temperature, as using a low sealing temperature avoids unnecessary exposure of the contents of the package to deteriorating conditions.

[0038] Another aspect contributing to the requirements for such vacuum packaging materials relates to the recyclability of the materials used in the packaging. Given the ongoing desire to increase the proportion of packaging materials that can withstand the recycling process, in order to reduce waste and raw material consumption, it is necessary to produce packaging suitable for recycling. A specific way to contribute to this goal is to ensure that the polymeric materials used in the packaging produced from polymeric film materials are of the same polymer type. In recycling technologies, film materials containing multiple polymer types are not suitable for a number of recycling methods. The more consistent the composition of the material stream for recycling, the more suitable this stream is for recycling.

[0039] Therefore, it is desirable to ensure that the packaging contains a certain high proportion of polymeric materials of the same class of materials. Typically, it is desirable for the packaging to contain at least 90% by weight, or at least 95% by weight, or even at least 97% by weight of polymeric materials of the same class. Such packaging is typically referred to as mono-material packaging.

[0040] Therefore, this places further requirements on the solutions for vacuum packaging, in that they are desired to contain at least 90% by weight of polymeric materials of the same class.

[0041] As can be understood, it is desirable for the packaging to exhibit a particularly high degree of such properties while also providing a mono-material solution. Achieving this remains the subject of development and is now achieved according to the present invention by: a packaging for storing frozen items comprising a laminate film, wherein the laminate film comprises at least a first layer and a second layer, wherein

[0042] · The first layer is a biaxially oriented polyethylene film layer; and

[0043] · The second layer is a second polyethylene film layer;

[0044] The packaging contains ≥90.0 wt%, preferably ≥95.0 wt%, more preferably ≥97.0 wt% of polyethylene based on the total weight of the laminated film.

[0045] Such packaging exhibits a desirably high impact strength at temperatures below 0 °C, for example at -25 °C, and presents a mono-material solution that allows for further appropriate processing of the packaging via recycling techniques.

[0046] The second polyethylene film layer can be, for example, a blown extrusion film, a cast extrusion film, a uniaxially oriented film, or a biaxially oriented polyethylene film.

[0047] The first layer and the second layer can be joined together, for example, via lamination, preferably where the joining occurs via an adhesive layer disposed between the first layer and the second layer. Such an adhesive layer can be in the form of a polyurethane-based adhesive, where the adhesive can be a solvent-based adhesive or a solventless adhesive.

[0048] The laminate can be formed by applying the adhesive to the surface of the first film or the second film and bringing that surface into contact with the surface of the second film, preferably by applying contact pressure. Such lamination can be carried out in a continuous process where the film to which the adhesive has been applied is brought into contact with the other film, and the contact pressure is provided by continuously rotating rollers, after which the laminate is wound onto a reel.

[0049] In an alternative embodiment, the adhesive is a hot-melt adhesive, which is applied to the film surface in a molten form. Such a hot-melt adhesive can be, for example, a thermoplastic material that exhibits proper adhesion to the first and second films. For example, such a hot-melt adhesive can be a polyethylene-based material. Another advantage provided by this embodiment is that it increases the content of polyethylene material in the laminate and thus improves the suitability of the material for recycling as a mono-material product. Specifically, such a polyethylene-based material that can be used as a hot-melt adhesive can be a functionalized polyethylene, such as maleic anhydride-grafted polyethylene. Such polyethylene exhibits excellent adhesive properties and is thus particularly suitable for the production of high-quality laminates.

[0050] The first layer can have a thickness of, for example, ≥15 and ≤75 μm, preferably ≥20 and ≤70 μm, even more preferably ≥30 and ≤60 μm.

[0051] The second layer can have the following thickness:

[0052] When the second layer is a blown extrusion film or a cast extrusion film: ≥40 and ≤300 μm, preferably ≥40 and ≤100 μm, preferably ≥50 and ≤80 μm, more preferably ≥50 and ≤70 μm; or

[0053] When the second layer is a uniaxially oriented film or a biaxially oriented film: ≥15 and ≤75 μm, preferably ≥20 and ≤70 μm, even more preferably ≥30 and ≤60 μm.

[0054] In the context of the present invention, a uniaxially oriented film should be understood as a film formed by cast extrusion and subjected to orientation in the longitudinal direction of the film production line at a temperature below the melting temperature of the film material. A biaxially oriented film should be understood as a film formed by cast extrusion and subjected to orientation in both the longitudinal and transverse directions of the film production line at a temperature below the melting temperature of the film material.

[0055] In the package of the present invention, the laminated film is preferably arranged such that the first layer faces the inside of the package compared to the second layer, and the second layer faces the outside of the package compared to the first layer.

[0056] A printed layer can be provided on the surface of the first layer arranged towards the outside of the package in the laminate.

[0057] In the context of the present invention, a biaxially oriented film should be understood as a film produced by drawing the film in both the longitudinal direction (MD) and the transverse direction (TD), where the longitudinal direction is the direction in which the film is extruded from the extrusion process, and the transverse direction is the direction perpendicular to the MD in the plane of the film. The biaxial drawing can be carried out sequentially or simultaneously. Such drawing should be applied at a drawing temperature below the melting point of the film.

[0058] The polymer used in the biaxially oriented film has a density of ≥910 and ≤930 kg / m 3 Preferably, the polymer has a density of ≥910 and ≤925 kg / m 3 More preferably, the polymer has a density of ≥915 and ≤925 kg / m 3 Even more preferably, the polymer has a density of ≥916 and ≤925 kg / m 3 or even more preferably ≥916 and ≤922 kg / m 3 of density.

[0059] The polymer used in the biaxially oriented film has a melt mass flow rate, also known as MFR2, measured at 190 °C under a load of 2.16 kg, of ≥0.2 and ≤5.0 g / 10 min, preferably ≥0.5 or ≥0.6 and ≤5.0 g / 10 min, preferably ≥0.5 or ≥0.6 and ≤4.0 g / 10 min, more preferably ≥0.8 and ≤3.5 g / 10 min, even more preferably ≥1.0 and ≤3.0 g / 10 min, even more preferably ≥1.0 and ≤2.5 g / 10 min.

[0060] Polymers used in biaxially oriented films are characterized in particular by their a-TREF fingerprint, i.e., they have a specific distribution of fractions of the polymer that are eluted in a-TREF within a specifically defined temperature range during fractionation. Specifically, the polymers according to the invention have a fraction that is eluted in a-TREF at a temperature > 94.0 °C and is ≥ 20.0 wt% relative to the total weight of the polymer. More preferably, the polymer has a fraction eluted at > 94.0 °C of ≥ 25.0 wt%, even more preferably ≥ 30.0 wt%, still even more preferably ≥ 35.0 wt%.

[0061] In the field of polyethylene, the fraction of the polymer that is eluted in a-TREF at a temperature > 94.0 °C reflects the amount of linear polymer material present in the specific polymer. In this polymer having a specific amount of material in this fraction, this indicates that a certain amount of linear polymer material should be present.

[0062] Furthermore, the polymers used in biaxially oriented films have a fraction that is eluted in a-TREF at a temperature ≤ 30.0 °C and is ≥ 8.0 wt% relative to the total weight of the polymer. The fraction eluted at a temperature ≤ 30 °C in the context of the present invention can be calculated by subtracting from 100% the sum of the fraction eluted at > 94 °C and the fraction eluted at > 30 °C and ≤ 94 °C, so that the fraction eluted at ≤ 30 °C, the fraction eluted at > 30 °C and ≤ 94 °C, and the fraction eluted at > 94 °C together amount to 100.0 wt%. The fraction eluted at ≤ 30 °C is preferably ≥ 9.0 wt%, more preferably ≥ 10.0 wt%, even more preferably ≥ 11.0 wt%.

[0063] Preferably, the fraction eluted in a-TREF at a temperature ≤ 30.0 °C is ≥ 8.0 and ≤ 16.0 wt% relative to the total weight of the polymer, more preferably ≥ 9.0 and ≤ 14.0 wt%, even more preferably ≥ 10.0 and ≤ 14.0 wt%; and / or preferably, the fraction eluted in a-TREF at a temperature > 94.0 °C is ≥ 20.0 and ≤ 50.0 wt% relative to the total weight of the polymer, more preferably ≥ 25.0 and ≤ 45.0 wt%, even more preferably ≥ 30.0 and ≤ 40.0 wt%; and / or preferably, the fraction eluted in a-TREF at a temperature > 30.0 °C and ≤ 94.0 °C is ≥ 40.0 and ≤ 64.0 wt%, more preferably ≥ 45.0 and ≤ 60.0 wt%, even more preferably ≥ 45.0 and ≤ 55.0 wt%.

[0064] Preferably, the heavy fraction eluted in a-TREF at a temperature > 30.0 °C and ≤ 94.0 °C is higher than the heavy fraction eluted in a-TREF at a temperature > 94.0 °C. Preferably, the fraction eluted at > 30.0 °C and ≤ 94.0 °C is at least 5.0 wt% higher than the fraction eluted at > 94.0 °C, where the fraction is expressed relative to the total weight of the polymer.

[0065] According to the present invention, the analysis of temperature rising elution fractionation (also known as a-TREF) can be carried out using Polymer Char Crystaf-TREF 300, using a solution containing a 4 mg / ml sample prepared in 1,2-dichlorobenzene, stabilized at 150 °C for 1 hour with 1 g / l Topanol CA (1,1,3-tris(3-tert-butyl-4-hydroxy-6-methylphenyl)butane) and 1 g / l Irgafos 168 (tris(2,4-di-tert-butylphenyl) phosphite). The solution can be additionally stabilized for 45 minutes at 95 °C with continuous stirring at 200 rpm before analysis. For analysis, the solution is crystallized from 95 °C to 30 °C using a cooling rate of 0.1 °C / min. Elution is carried out from 30 °C to 140 °C using a heating rate of 1 °C / min. The apparatus is cleaned at 150 °C.

[0066] Specifically, a-TREF can be carried out using Polymer Char Crystaf-TREF 300, using a solution containing 4 mg / ml of polymer in 1,2-dichlorobenzene, where the solution is stabilized at 150 °C for 1 hour with 1 g / l 1,1,3-tris(3-tert-butyl-4-hydroxy-6-methylphenyl)butane and 1 g / l tris(2,4-di-tert-butylphenyl) phosphite, and optionally the solution is additionally stabilized for 45 minutes at 95 °C with continuous stirring at 200 rpm, where the solution is crystallized from 95 °C to 30 °C using a cooling rate of 0.1 °C / min before analysis, and elution is carried out from 30 °C to 140 °C using a heating rate of 1 °C / min, and where the apparatus has been cleaned at 150 °C.

[0067] In the context of the present invention, CCDB is determined according to formula I:

[0068]

[0069] where

[0070] ·T n-2 is the moment calculated according to formula II:

[0071]

[0072] and

[0073] ·Tz+2 is the moment calculated according to Equation III:

[0074]

[0075] where

[0076] · w(i) is the sampling weight fraction of sample (i) taken at temperature T(i) relative to the total sample weight in the a-TREF analysis, in weight %, where T(i) > 30 °C and the area under the a-TREF curve is normalized to a surface area = 1 for T(i) > 30 °C; and

[0077] · T(i) is the temperature at which sample (i) is taken in the a-TREF analysis, in °C.

[0078] The polymer used in the biaxially oriented film as used in the present invention may be, for example, linear low density polyethylene. For example, the polymer may be linear low density polyethylene produced using a Ziegler-Natta type catalyst. The polymer as used in the present invention may be produced, for example, using a gas phase polymerization process, using a slurry phase polymerization process, or using a solution polymerization process.

[0079] The polymer in the biaxially oriented film may, for example, comprise ≥ 80.0 wt% of structural moieties derived from ethylene and / or ≥ 5.0 wt% and < 20.0 wt% of structural moieties derived from 1-hexene, based on the total weight of the polymer. Preferably, the polymer comprises ≥ 85.0 wt%, more preferably ≥ 88.0 wt% of structural moieties derived from ethylene. Preferably, the polymer comprises ≥ 80.0 wt% and ≤ 99.0 wt%, more preferably ≥ 85.0 wt% and ≤ 95.0 wt%, even more preferably ≥ 88.0 wt% and ≤ 93.0 wt% of structural moieties derived from ethylene.

[0080] The polymer in the biaxially oriented film may, for example, comprise ≥ 5.0 wt%, preferably ≥ 7.0 wt%, more preferably ≥ 8.0 wt%, even more preferably ≥ 9.0 wt% of structural moieties derived from 1-hexene, based on the total weight of the polymer. Preferably, the polymer comprises structural moieties derived from ethylene and ≥ 5.0 wt%, preferably ≥ 7.0 wt%, more preferably ≥ 8.0 wt%, even more preferably ≥ 9.0 wt% of structural moieties derived from 1-hexene. More preferably, the polymer comprises structural moieties derived from ethylene and ≥ 5.0 wt% and ≤ 20.0 wt%, preferably ≥ 7.0 wt% and ≤ 17.0 wt%, more preferably ≥ 8.0 wt% and ≤ 15.0 wt%, even more preferably ≥ 9.0 wt% and ≤ 13.0 wt% of structural moieties derived from 1-hexene.

[0081] For example, the polymer in the biaxially oriented film may comprise ≥80.0% by weight of structural moieties derived from ethylene and ≥5.0% by weight, preferably ≥7.0% by weight, more preferably ≥8.0% by weight, even more preferably ≥9.0% by weight of structural moieties derived from 1 - hexene. Preferably, the polymer comprises ≥80.0% by weight of structural moieties derived from ethylene and ≥5.0% by weight and ≤20.0% by weight, preferably ≥7.0% by weight and ≤17.0% by weight, more preferably ≥8.0% by weight and ≤15.0% by weight, even more preferably ≥9.0% by weight and ≤13.0% by weight of structural moieties derived from 1 - hexene.

[0082] In certain embodiments, the polymer as used in the biaxially oriented film consists of structural moieties derived from ethylene and structural moieties derived from 1 - hexene. For example, the polymer may consist of structural moieties derived from ethylene and ≥5.0% by weight, preferably ≥7.0% by weight, more preferably ≥8.0% by weight, even more preferably ≥9.0% by weight of structural moieties derived from 1 - hexene. Preferably, the polymer consists of structural moieties derived from ethylene and ≥5.0% by weight and ≤20.0% by weight, preferably ≥7.0% by weight and ≤17.0% by weight, more preferably ≥8.0% by weight and ≤15.0% by weight, even more preferably ≥9.0% by weight and ≤13.0% by weight of structural moieties derived from 1 - hexene.

[0083] The amount of 1 - hexene - derived structural moieties in the polyethylene can be determined by 13 13C NMR on a Bruker Avance 500 spectrometer equipped with a cryogenic probe operating at 125 °C, whereby the sample is dissolved in C2D2Cl4 containing DBPC as a stabilizer at 130 °C.

[0084] In certain embodiments of the present invention, it is preferred that the polymer has a specific degree of long - chain branching. In the context of the present invention, long - chain branching should be understood to reflect the presence of certain polymeric side - chains that do not originate from the incorporation of comonomers but can be caused, for example, by the reaction of a polymeric chain containing unsaturation with another growing chain at a catalytic site. In certain embodiments, a certain amount of such long - chain branching is desired. In the context of the present invention, an indicator of the presence of long - chain branching can be, for example, the storage modulus G' at a certain loss modulus G". A certain high storage modulus at a defined loss modulus indicates the presence of a certain amount of long - chain branching in the polymer. A particularly preferred indicator of a certain degree of long - chain branching is the storage modulus at a loss modulus of 10.0 kPa and the storage modulus at a loss modulus of 1.0 kPa. The storage modulus and the loss modulus can be determined, for example, according to ISO6721 - 10(2015).

[0085] For example, the polymer in the biaxially oriented film may have a storage modulus of >2.0 kPa, preferably >2.2 kPa, more preferably >2.5 kPa, measured at a loss modulus of 10.0 kPa. For example, the polymer may have a storage modulus of >50 Pa, preferably >75 Pa, more preferably >100 Pa, measured at a loss modulus of 1.0 kPa. For example, the polymer may have a storage modulus of >50 Pa, preferably >75 Pa, more preferably >100 Pa and <150 Pa, measured at a loss modulus of 1.0 kPa. For example, the storage modulus at a loss modulus of 10.0 kPa may be >2.0 kPa and the storage modulus at a loss modulus of 1.0 kPa may be >50 Pa, preferably the storage modulus at a loss modulus of 10.0 kPa >2.5 kPa and the storage modulus at a loss modulus of 1.0 kPa >50 and <150 Pa. The storage modulus and the loss modulus may be measured at a temperature of 190 °C according to ISO 6721-10 (2015).

[0086] The polymer in the biaxially oriented film may, for example, contain an unsaturation of <250, preferably <200, or >100 and <250 per 1,000,000 chain carbon atoms, where the unsaturation is measured as the sum of vinyl unsaturation, vinylene unsaturation, divinylene unsaturation, and trialkyl unsaturation determined via 1 1H NMR. The number of unsaturations may be measured by 1 1H NMR on a Bruker Avance 500 spectrometer equipped with a cryogenic probe operating at 125 °C, whereby the sample is dissolved in C2D2Cl4 containing DBPC as a stabilizer at 130 °C.

[0087] The polymer in the biaxially oriented film may, for example, have an M w w n / M z n n ratio of >4.0, preferably >4.0 and <10.0, more preferably >5.0 and <8.0. For example, the polymer may have an M n w w / M z z w / M n n z ratio of >15.0, preferably >15.0 and <40.0, preferably >20.0 and <30.0, where M n n

[0088] Preferably, the polymer used in the biaxially oriented film has a log(M w ) in the range of 4.0 to 5.5, and the slope of the curve of the number of CH3 branches per 1000 C atoms versus log(M w ) is negative, where the number of CH3 branches is determined by SEC-DV using an IR5 infrared detector in accordance with ASTM D6474 (2012).

[0089] The polymer in the biaxially oriented film may have, for example, an M of > 75 kg / mol, preferably > 100 kg / mol, such as > 75 and < 200 kg / mol, preferably > 100 and < 150 kg / mol w . The polymer may have, for example, an M of > 15 kg / mol, preferably > 20 kg / mol, such as > 15 and < 40 kg / mol, preferably > 20 and < 30 kg / mol n . The polymer may have an M of > 300 kg / mol, preferably > 400 kg / mol, such as > 300 and < 700 kg / mol, preferably > 400 and < 650 kg / mol z . M w , M z and / or M n such properties may contribute to the improvement of the stretchability of the film produced using the polymer of the present invention.

[0090] The biaxially oriented film may, for example, comprise a polymer having a structural moiety derived from ethylene and a structural moiety derived from 1-hexene, wherein the polymer has:

[0091] (a) a density of ≥ 910 and ≤ 930 kg / m 3 , preferably ≥ 916 and ≤ 925 kg / m 3 , as determined in accordance with ASTM D792 (2008);

[0092] (b) a melt mass flow rate of ≥ 0.2, preferably ≥ 0.5 or ≥ 0.6, and ≤ 5.0 g / 10 min as determined in accordance with ASTM D1238 (2013) at a temperature of 190 °C and a load of 2.16 kg;

[0093] (c) a fraction eluting in analytical temperature rising elution fractionation (a-TREF) at a temperature of ≤ 30.0 °C of ≥ 8.0 wt%, preferably ≥ 11.0 wt%, based on the total weight of the polymer; and

[0094] (d) a fraction eluting in a-TREF at a temperature of > 94.0 °C of ≥ 20.0 wt%, based on the total weight of the polymer; and preferably

[0095] (e) A fraction that elutes in a-TREF at a temperature > 30.0 °C and ≤ 94.0 °C and is ≥ 40.0 and ≤ 64.0 wt% based on the total weight of the polymer.

[0096] In certain embodiments, the present invention also relates to a package comprising a biaxially oriented polyethylene film, wherein the biaxially oriented film comprises a polymer having structural moieties derived from ethylene and structural moieties derived from 1-hexene, and wherein the polymer has:

[0097] (a) A density of ≥ 916 and ≤ 925 kg / m 3 determined according to ASTM D792 (2008);

[0098] (b) A melt mass flow rate of ≥ 0.6 and ≤ 5.0 g / 10 min determined according to ASTM D1238 (2013) at a temperature of 190 °C and a load of 2.16 kg;

[0099] (c) A fraction of ≥ 11.0 wt% based on the total weight of the polymer that elutes in analytical temperature rising elution fractionation (a-TREF) at a temperature ≤ 30.0 °C; and

[0100] (d) A fraction of ≥ 20.0 wt% based on the total weight of the polymer that elutes in a-TREF at a temperature > 94.0 °C; and

[0101] (e) A fraction that elutes in a-TREF at a temperature > 30.0 °C and ≤ 94.0 °C and is ≥ 40.0 and ≤ 64.0 wt% based on the total weight of the polymer.

[0102] The package may, for example, comprise a biaxially oriented film that is oriented longitudinally to an extent of 3 to 10, and / or the film is oriented transversely to an extent of 5 to 15, where the degree of orientation is the ratio of the size of the film in a particular direction after orientation to the size before orientation.

[0103] In certain embodiments, the present invention also relates to a method of producing a package comprising a biaxially oriented film.

[0104] For example, in certain embodiments, the present invention also relates to a method of producing a package comprising a biaxially oriented film, the biaxially oriented film comprising a polymer having structural moieties derived from ethylene and structural moieties derived from 1-hexene, and wherein the polymer has:

[0105] (a) A density of ≥ 916 and ≤ 925 kg / m 3 determined according to ASTM D792 (2008);

[0106] (b) A melt mass flow rate of ≥ 0.6 and ≤ 5.0 g / 10 min as measured according to ASTM D1238 (2013) at a temperature of 190 °C and a load of 2.16 kg;

[0107] (c) A fraction eluting in analytical temperature rising elution fractionation (a-TREF) at a temperature of ≤ 30.0 °C and being ≥ 11.0 wt% relative to the total weight of the polymer; and

[0108] (d) A fraction eluting in a-TREF at a temperature of > 94.0 °C and being ≥ 20.0 wt% relative to the total weight of the polymer; and

[0109] (e) A fraction eluting in a-TREF at a temperature of > 30.0 °C and ≤ 94.0 °C and being ≥ 40.0 and ≤ 64.0 wt% relative to the total weight of the polymer.

[0110] The film can for example have an orientation of at least 4.0 in the longitudinal direction. In the context of the present invention, orientation can also be referred to as stretching. The orientation in the longitudinal direction should be understood as the ratio of the length of a certain amount of material in the longitudinal direction after having been subjected to a tensile force in the longitudinal direction to the length that the same amount of material had before being subjected to the tensile force in the longitudinal direction.

[0111] The film can for example have an orientation of at least 8 in the transverse direction. The orientation or stretching in the transverse direction should be understood as the ratio of the width of the film after having been subjected to a tensile force in the transverse direction to the width of the film before being subjected to the tensile force in the transverse direction.

[0112] The stretching in the transverse direction can for example be achieved by the following steps: clamping the film in clamps located on either side of the film at a certain distance apart, applying a certain amount of heat to the film to ensure that the film is at a certain temperature, and applying a certain amount of force outward from the plane of the film to the clamps in the transverse direction. This stretching can for example be carried out in a continuous operation.

[0113] The biaxially oriented film can for example contain > 80.0 wt%, preferably > 85.0 wt%, preferably > 90.0 wt%, more preferably > 95.0 wt%, for example > 80.0 and < 98.0 wt%, or > 90.0 and < 98.0 wt% of a polymer relative to the total weight of the biaxially oriented film.

[0114] In the package according to the present invention, in certain embodiments, a sealing layer can be present on the surface of the first layer facing the inside of the package. For example, the package can be a heat-sealable bag.

[0115] The sealing layer can for example contain a first polyethylene and optionally a second polyethylene, wherein the first polyethylene has:

[0116] · a material fraction that elutes in analytical temperature rising elution fractionation (a-TREF) at a temperature > 94.0 °C and is ≤ 5.0 wt%, preferably ≤ 1.0 wt%, based on the total weight of the first polyethylene; and / or

[0117] · a shear storage modulus G' > 700 Pa measured at a shear loss modulus G'' = 5000 Pa, where G' and G'' are measured at 190 °C according to ISO 6721-10 (2015); and / or

[0118] · a chemical composition distribution breadth (CCDB) of ≥ 5.0, preferably ≥ 10.0, preferably ≥ 15.0, preferably ≥ 20.0, preferably ≥ 5.0 and ≤ 30.0.

[0119] The sealing layer may for example comprise ≥ 15.0 wt%, ≥ 25.0 wt%, ≥ 50.0 wt%, ≥ 75.0 wt%, or ≥ 85.0 wt% of the first polyethylene, based on the total weight of the sealing layer. The sealing layer may for example comprise ≥ 15.0 and ≤ 50.0 wt% of the first polyethylene, based on the total weight of the sealing layer. The sealing layer may for example comprise ≥ 15.0 and ≤ 50.0 wt% of the first polyethylene and a certain proportion of the second polyethylene. In certain embodiments, the sealing layer may contain the first polyethylene as the only polyethylene material. For example, the sealing layer may comprise ≥ 30.0 and ≤ 99.0 wt%, or ≥ 30.0 and ≤ 97.0 wt% of the first polyethylene.

[0120] The first polyethylene may for example comprise ≥ 80.0 wt% of structural moieties derived from ethylene and / or ≥ 5.0 wt% and < 20.0 wt% of structural moieties derived from 1-octene, based on the total weight of the first polyethylene.

[0121] The second polyethylene may be for example a polymer having structural moieties derived from ethylene and structural moieties derived from 1-hexene, wherein the polymer has:

[0122] (a) a density of ≥ 910 and ≤ 930 kg / m 3 、preferably ≥ 916 and ≤ 925 kg / m 3 measured according to ASTM D792 (2008);

[0123] (b) a melt mass flow rate of ≥ 0.2, preferably ≥ 0.5 or ≥ 0.6, and ≤ 5.0 g / 10 min measured at a temperature of 190 °C and a load of 2.16 kg according to ASTM D1238 (2013);

[0124] (c) a fraction that elutes in analytical temperature rising elution fractionation (a-TREF) at a temperature of ≤ 30.0 °C and is ≥ 8.0 wt%, preferably ≥ 11.0 wt%, based on the total weight of the polymer; and

[0125] (d) a fraction that elutes in a-TREF at a temperature > 94.0 °C and is ≥ 20.0 wt% based on the total weight of the polymer; and preferably

[0126] (e) a fraction that elutes in a-TREF at a temperature > 30.0 °C and ≤ 94.0 °C and is ≥ 40.0 and ≤ 64.0 wt% based on the total weight of the polymer.

[0127] Preferably, the second polyethylene in the sealing layer is the same as the polymer in the biaxially oriented film.

[0128] In one embodiment, the present invention also relates to the use of a biaxially oriented film comprising a polymer having structural moieties derived from ethylene and structural moieties derived from 1-hexene, wherein the polymer has:

[0129] (a) a density of ≥ 910 and ≤ 930 kg / m 3 、preferably ≥ 916 and ≤ 925 kg / m 3 determined according to ASTM D792 (2008);

[0130] (b) a melt mass flow rate of ≥ 0.2, preferably ≥ 0.5 or ≥ 0.6, and ≤ 5.0 g / 10 min determined according to ASTM D1238 (2013) at a temperature of 190 °C and a load of 2.16 kg;

[0131] (c) a fraction that elutes in analytical temperature rising elution fractionation (a-TREF) at a temperature of ≤ 30.0 °C and is ≥ 8.0 wt%, preferably ≥ 11.0 wt%, based on the total weight of the polymer; and

[0132] (d) a fraction that elutes in a-TREF at a temperature > 94.0 °C and is ≥ 20.0 wt% based on the total weight of the polymer; and preferably

[0133] (e) a fraction that elutes in a-TREF at a temperature > 30.0 °C and ≤ 94.0 °C and is ≥ 40.0 and ≤ 64.0 wt% based on the total weight of the polymer;

[0134] for improving the cold shock strength at -25 °C of a package.

[0135] The frozen articles to be stored using the packaging of the present invention can be, for example, foodstuffs such as frozen fruits and vegetables, meat and fish products, dairy products, pre-baked bread and pastries, or processed potato products. For example, such a packaging can contain a quantity of foodstuffs of final consumer size, such as foodstuffs having a volume between 0.5 liters and 5.0 liters, or between 0.5 liters and 2.0 liters. Example

[0136] Production of biaxially oriented polyethylene film (BOPE film):

[0137] A multilayer A-B-C polyethylene film was produced by cast extrusion using a twin-screw extruder, wherein the core layer B was extruded at 60 kg / h and each of the layers A and C was extruded at 6.0 kg / h via a separate extruder, thereby producing a three-layer structure comprising 7 wt% layer A, 86 wt% layer B and 7 wt% layer C. The extrusion was carried out at 260 °C. The cast film was extruded through a die having a die gap of 3.0 mm at a speed of 9 m / min.

[0138] After extrusion, the film was cooled via a water bath. The film was oriented longitudinally via a plurality of orientation rollers at a temperature of 66 to 96 °C to a degree of draw in the longitudinal direction of 12. Subsequently, at a temperature decreasing from 146 °C to 110 °C, the film was subjected to stretching in the transverse direction to obtain a biaxially oriented film (film 1) having a thickness of 19 μm. The film was subjected to corona treatment at 25 W·min / m 2 Similarly, a film (film 4) having a thickness of 40 μm was produced with an increased throughput.

[0139] Formulation of the BOPE film:

[0140] Layer A: 72 wt% SABIC BX202, 3 wt% Constab AB06001LD, 25 wt% SABIC COHERE8112

[0141] Layer B: 100 wt% SABIC BX202

[0142] Layer C: 97 wt% SABIC BX202, 3 wt% Constab AB06001LD

[0143] Production of biaxially oriented polypropylene film (BOPP film):

[0144] A multilayer A-B-C polypropylene film was produced by cast extrusion using a twin-screw extruder, wherein the core layer B was extruded at 52 kg / h and each of the layers A and C was extruded at 6.0 kg / h via a separate extruder, thereby producing a three-layer structure comprising 7 wt% layer A, 86 wt% layer B and 7 wt% layer C. The extrusion was carried out at 260 °C. The cast film was extruded through a die having a die gap of 3.0 mm at a speed of 9 m / min.

[0145] After extrusion, the film is cooled via a water bath. The film is oriented longitudinally via a plurality of orientation rollers at a temperature of 80 to 106 °C to achieve a draw ratio of 12 in the longitudinal direction. Subsequently, at a temperature decreasing from 190 °C to 160 °C, the film is subjected to transverse stretching to obtain a biaxially oriented film with a thickness of 25 μm. The film is subjected to corona treatment at 24 W·min / m 2 under.

[0146] Formulation of BOPP film 2:

[0147] Layer A: 98 wt% Adsyl 5C30F, 2 wt% Schulman AB PP 05 SC Layer B: 100 wt% SABIC521P

[0148] Layer C: 98 wt% Adsyl 5C30F, 2 wt% Schulman AB PP 05 SC

[0149] Production of blown film:

[0150] The single-layer blown film (film 3) is produced using SABIC BX202 and a Kuhne blown film extruder, which operates at an extruder temperature of 200 °C, at 96 RPM and with a polyethylene feed of 24.8 kg / h. The pressure before the filter is 113 bar and the pressure after the filter is 74 bar. The film extrusion equipment is provided with a 120 mm die with a die gap of 2.3 mm. The production line is operated at a cold draw line height of 30 cm and a blow-up ratio of 2.5 with a winder speed of 18 m / min. The resulting film has a thickness of 25 μm.

[0151] Another blown film (film 5) is produced as a 3-layer film with a thickness of 60 μm having an A / B / C structure. The blown film extrusion production line is fed by 3 extruders for each layer, where the formulation is Layer A: 75 wt% SABIC SUPEER 7118NE and 25 wt% SABIC LDPE2501N0; Layer B: 75 wt% SABIC HDPE F04660 and 25 wt% SABIC LDPE2501N0; and Layer C: 25 wt% SABIC COHERE S100 and 75 wt% SABIC LDPE 2501N0. Film 5 consists of 30 wt% Layer A (17 μm), 60 wt% Layer B (35 μm), and 10 wt% Layer C (8 μm). The combined output of the extruders is 200 kg / h. The winder speed is 23 m / min; other conditions are the same as for film 3.

[0152] Film lamination

[0153] Using a Drytex drying tunnel laminating device, the laminating speed was 5 m / min, the hot air drying temperature was 50 °C, and 94 ml / m 2 of Henkel Liofol 3640 adhesive was used for roll-to-roll lamination.

[0154] The following properties were measured for Films 1-3 prepared as above:

[0155] Examples Film 1 Film 2 Film 3 BOPE BOPP Blown PE Thickness (μm) 19 25 25 Impact strength at 23°C (g / 25μm) 508 954 87 MD breaking tensile strength at -25°C (MPa) 59 154 86 MD breaking tensile strength at 23°C (MPa) 39 121 62 MD breaking elongation at -25°C (%) 240 161 603 MD breaking elongation at 23°C (%) 288 191 556 MD tear resistance (g / 25μm) 22 8 291 TD tear resistance (g / 25μm) 5 4 704 Puncture resistance at 23°C (N / 25μm) 118 247 72 Puncture resistance at -25°C (N / 25μm) 109 217 43 Sealing strength of the sealant produced at 80°C (N / 15mm) 0.07 0.07 0.08 Sealing strength of the sealant produced at 90°C (N / 15mm) 0.57 0.17 0.41 Sealing strength of the sealant produced at 100°C (N / 15mm) 5.8 0.51 4.9 Sealing strength of the sealant produced at 110°C (N / 15mm) 7.0 3.5 5.8 Sealing strength of the sealant produced at 120°C (N / 15mm) 10.5 3.2 6.0

[0156] Wherein:

[0157] · Impact strength was measured according to ASTM D1709A (2016);

[0158] · MD tensile strength at break was measured longitudinally for the film using an initial sample length of 50 mm and a test speed of 500 mm / min according to ASTM D882 (2018);

[0159] · MD elongation at break was measured longitudinally for the film at room temperature using an initial sample length of 50 mm and a test speed of 500 mm / min according to ASTM D882 (2018);

[0160] · Tear resistance was measured in the longitudinal (MD) and transverse (TD) directions according to the method of ASTM D1922 (2015).

[0161] · Puncture resistance was the maximum force measured according to ASTM D5748-95 (2012), expressed in N;

[0162] · Heat seal strength was measured for 15 mm wide specimens according to ASTM F88 using Method A. Wing seals were prepared at different temperatures according to ASTM F2029. Two samples of the same film were compressed together, with Layer C of the first film sample contacting Layer C of the second film sample. A seal was produced by applying a force of 3.0 bar for 1.0 s, with a 25 μm cellophane sheet used to protect the film. The press used to prepare the seal was heated to various temperatures to identify the strength of the seal produced at different temperatures. The seal strength was tested using a tensile testing machine at a test speed of 200 mm / min and a grip distance of 10 mm. The maximum load was recorded as the seal strength.

[0163] Production of the laminate

[0164] The following laminates were produced according to the above method:

[0165] Laminates L1 L2 L3 BO film Film 1 Film 5 BOPET Blown film Film 5 Film 5 Film 5 Thickness (μm) 80 100 72 Fracture puncture energy (J) 2.7 5.7 1.8 Fracture puncture energy (J / μm) 0.034 0.057 0.025

[0166] · The puncture energy at break is determined in accordance with ASTM D5748-95(2012), expressed in J, or, when corrected for film thickness, in J / μm.

Claims

1. A package comprising a laminated film, wherein the laminated film comprises at least a first layer and a second layer, wherein: • The first layer is a biaxially oriented polyethylene film layer; and • The second layer is a second polyethylene film layer; wherein the packaging comprises ≥ 90.0% by weight of polyethylene, based on the total weight of the laminated film, wherein the biaxially oriented film layer comprises a polymer having structural moieties derived from ethylene and structural moieties derived from 1 - hexene, wherein the polymer has: (a) Density of ≥ 910 and ≤ 930 kg / m 3 determined according to ASTM D792 (2008); (b) a melt mass flow rate of ≥ 0.2 and ≤ 5.0 g / 10 min as measured according to ASTM D1238 (2013) at a temperature of 190 °C and a load of 2.16 kg; (c) a fraction eluting in temperature rising elution fractionation at a temperature of ≤ 30.0 °C of ≥ 8.0% by weight, based on the total weight of the polymer; (d) a fraction eluting in temperature rising elution fractionation at a temperature of > 94.0 °C of ≥ 20.0% by weight, based on the total weight of the polymer; and (e) a fraction eluting in temperature rising elution fractionation at a temperature of > 30.0 °C and ≤ 94.0 °C of ≥ 40.0 and ≤ 64.0% by weight, based on the total weight of the polymer.

2. The package according to claim 1, wherein the package is a package for storing frozen items; a package for storing liquid-flowing foods, liquid detergents, or liquid health products; or a package for storing items with sharp edges.

3. The package according to any one of claims 1-2, wherein the second polyethylene film layer is a blown extrusion film, a cast extrusion film, a uniaxially oriented film, or a biaxially oriented polyethylene film.

4. The package according to any one of claims 1-2, wherein the first layer and the second layer are laminated together.

5. The package according to claim 4, wherein the lamination occurs via an adhesive layer disposed between the first layer and the second layer.

6. The package according to any one of claims 1-2, wherein the thickness of the first layer is ≥ 15 and ≤ 75 μm.

7. The package according to any one of claims 1-2, wherein the thickness of the first layer is ≥ 30 and ≤ 60 μm.

8. The package according to any one of claims 1-2, wherein the thickness of the second layer is: • when the second layer is a blown extrusion film or a cast extrusion film: ≥ 40 and ≤ 100 μm; or • when the second layer is a uniaxially oriented film or a biaxially oriented film: ≥ 15 and ≤ 75 μm.

9. The package according to any one of claims 1-2, wherein the laminated film is arranged such that the first layer faces the interior of the package as compared to the second layer, and the second layer faces the exterior of the package as compared to the first layer.

10. The package according to any one of claims 1-2, wherein the polymer has ≥ 916 and ≤ 925 kg / m as measured according to ASTM D792 (2008)3 Density.

11. The package according to any one of claims 1-2, wherein the polymer has a melt mass flow rate of ≥ 0.5 and ≤ 5.0 g / 10 min as measured according to ASTM D1238 (2013) at a temperature of 190 °C and a load of 2.16 kg.

12. The package according to any one of claims 1-2, wherein the polymer has a melt mass flow rate of ≥ 0.6 and ≤ 5.0 g / 10 min as measured according to ASTM D1238 (2013) at a temperature of 190 °C and a load of 2.16 kg.

13. The package according to any one of claims 1-2, wherein the polymer has a fraction eluting in analytical temperature rising elution fractionation at a temperature of ≤ 30.0 °C that is ≥ 11.0 wt% based on the total weight of the polymer.

14. The package according to any one of claims 1-2, wherein the polymer comprises a structural moiety derived from ethylene of ≥ 80.0 wt% based on the total weight of the polymer and / or a structural moiety derived from 1-hexene of ≥ 5.0 wt% and < 20.0 wt%.

15. The package according to any one of claims 1-2, wherein the polymer has an M w / M n ratio of > 4.0, and / or wherein the polymer has an M z / M n ratio of > 15.0, where M n is the number average molecular weight, M w is the weight average molecular weight, and M z is the z average molecular weight, measured according to ASTM D6474 (2012).

16. The package according to any one of claims 1-2, wherein the polymer has an M w / M n ratio of > 4.0 and < 10.0, and / or wherein the polymer has an M z / M n ratio of > 15.0 and < 40.0, where M n is the number average molecular weight, M w is the weight average molecular weight, and M z is the z average molecular weight, measured according to ASTM D6474 (2012).

17. The package according to any one of claims 1-2, wherein a sealing layer is present on the surface of the first layer disposed towards the interior of the package.

18. The package according to any one of claims 1 - 2, wherein the package is a heat - sealed bag, sachet or vacuum package.

19. The package according to claim 17, wherein the sealing layer comprises a first polyethylene and optionally a second polyethylene, wherein the first polyethylene has: • a material fraction of ≤ 5.0 wt% relative to the total weight of the first polyethylene, eluting in temperature - rising elution fractionation at a temperature > 94.0 °C; and / or • a shear storage modulus G' > 700 Pa at a shear loss modulus G'' = 5000 Pa, G' and G'' being determined according to ISO 6721 - 10 (2015) at 190 °C; and / or • a chemical composition distribution breadth ≥ 5.

0.

20. The package according to claim 19, wherein the first polyethylene has a material fraction of ≤ 1.0 wt% relative to the total weight of the first polyethylene, eluting in temperature - rising elution fractionation at a temperature > 94.0 °C.

21. The package according to claim 19, wherein the first polyethylene has a chemical composition distribution breadth ≥ 10.

0.

22. The package according to claim 19, wherein the first polyethylene has a chemical composition distribution breadth ≥ 15.

0.

23. The package according to claim 19, wherein the first polyethylene has a chemical composition distribution breadth ≥ 20.

0.

24. The package according to claim 19, wherein the first polyethylene has a chemical composition distribution breadth ≥ 5.0 and ≤ 30.

0.

25. The package according to any one of claims 19 - 24, wherein: • The sealant layer comprises ≥ 15.0 and ≤ 50.0% by weight or ≥ 30.0 and ≤ 97.0% by weight of the first polyethylene, based on the total weight of the sealant layer; and / or • The first polyethylene comprises ≥ 80.0% by weight of structural moieties derived from ethylene and / or ≥ 5.0% and < 20.0% by weight of structural moieties derived from 1 - octene, based on the total weight of the first polyethylene.

26. The package according to any one of claims 19 - 24, wherein the second polyethylene is a polymer having structural moieties derived from ethylene and structural moieties derived from 1 - hexene, wherein the polymer has: (f) a density ≥ 910 and ≤ 930 kg / m 3 determined according to ASTM D792 (2008); (g) a melt mass - flow rate ≥ 0.2 and ≤ 5.0 g / 10 min determined according to ASTM D1238 (2013) at a temperature of 190 °C and a load of 2.16 kg; (h) a fraction eluted in an analytical temperature rising elution fractionation at a temperature of ≤ 30.0 °C and being ≥ 8.0% by weight based on the total weight of the polymer; and (i) a fraction eluted in an analytical temperature rising elution fractionation at a temperature of > 94.0 °C and being ≥ 20.0% by weight based on the total weight of the polymer.

27. The package according to claim 26, wherein the polymer has (j) a fraction eluted in an analytical temperature rising elution fractionation at a temperature of > 30.0 °C and ≤ 94.0 °C and being ≥ 40.0% and ≤ 64.0% by weight based on the total weight of the polymer.

28. The package according to claim 26, wherein the second polyethylene in the sealing layer is the same as the polymer in the biaxially oriented film.

29. The package according to claim 26, wherein the polymer has a density of ≥ 916 and ≤ 925 kg / m 3 as determined according to ASTM D792 (2008).

30. The package according to claim 26, wherein the polymer has a melt mass flow rate of ≥ 0.5 and ≤ 5.0 g / 10 min as determined according to ASTM D1238 (2013) at a temperature of 190 °C and a load of 2.16 kg.

31. The package according to claim 26, wherein the polymer has a melt mass flow rate of ≥ 0.6 and ≤ 5.0 g / 10 min as determined according to ASTM D1238 (2013) at a temperature of 190 °C and a load of 2.16 kg.

32. The package according to claim 26, wherein the polymer has a fraction eluted in an analytical temperature rising elution fractionation at a temperature of ≤ 30.0 °C and being ≥ 11.0% by weight based on the total weight of the polymer.

33. The package according to claim 1, wherein the package is a package for storing food.

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