Recyclable plastic film

Abstract

The invention relates to a plastic film that comprises or consists of (a) a layer (a) which contains or is based on a polyolefin; (b) optionally a layer (b) which contains or is based on a functionalized polyolefin; (c) optionally a layer (c) which is based on a water-soluble polymer; (d) a layer (d) which contains or is based on a polyamide and / or a polyester; (e) optionally a layer (e) which is based on a water-soluble polymer; (f) optionally a layer (f) which contains or is based on a functionalized polyolefin; and (g) optionally a layer (g) which contains or is based on a polyolefin. The plastic film comprises at least one layer which contains or is based on a water-soluble polymer.

Description

Recyclable plastic film

[0001] The priority of German patent application No. 10 2022 213 878.3 of December 19, 2022 is claimed.

[0002] The invention relates to a plastic film which comprises or consists of (a) a layer (a) containing or based on polyolefin; (b) optionally a layer (b) containing or based on functionalized polyolefin; (c) optionally a layer (c) based on water-soluble polymer; (d) a layer (d) containing or based on polyamide and / or polyester; (e) optionally a layer (e) based on water-soluble polymer; (f) optionally a layer (f) containing or based on functionalized polyolefin; and (g) optionally a layer (g) containing or based on polyolefin; wherein the plastic film comprises at least one layer containing or based on water-soluble polymer.

[0003] Multilayer films with a polyolefin-containing layer and a non-(mainly) polyolefin-containing layer, for example a polyamide or polyester-containing layer, are used in a wide variety of applications due to their technical properties.

[0004] Such multilayer films cannot be recycled economically and ecologically in the spirit of a circular economy. This is because the main raw materials, such as polyolefins, polyamides, or polyesters, cannot be sufficiently separated from one another.

[0005] Recycling the main raw materials as composites runs counter to the spirit of a circular economy and usually results in downcycling or energy recovery. In the spirit of a circular economy, it is therefore necessary that the main raw materials can be separated as accurately as possible during recycling and recycled. Using a multilayer film as an example, this means separating the main raw materials into polypropylene and polyamide streams.

[0006] Various processes for recycling plastic films are known from the state of the art. Recyclable plastic films have been developed.

[0007] DE 41 20 685 A1 discloses a laminate material containing at least one layer of thermoplastic material and possessing a latently inherent delamination potential. The thermoplastic layer carries a release layer of water-soluble or water-dispersible organic material on at least one side.

[0008] DE 10 2012 006 416 Al concerns a metal-free multilayer film with a basis weight of < 33 g / m 2 , a shrinkage of < 10% at 90°C (both in machine direction and cross to machine direction, determined as dimensional change according to DIN 53377) and a at least six-layer layer structure comprising a layer (a) composed of at least one thermoplastic olefin homo- or copolymer as one of the outer layers, an adhesion promoter layer (b), a layer (c) composed of at least one homo- and / or copolyamide, at least one internal gas barrier layer (d) adjacent to layer (c) which differs from layers (c) and (e) at least in the composition of the polymer component(s); a layer (e) composed of at least one homo- and / or copolyamide adjacent to the gas barrier layer (d), and a layer (i) composed of at least one homo- and / or copolyamide as one of the outer layers, a use of such a multilayer film for producing a buoyancy body, and a buoyancy body made from such a multilayer film.

[0009] DE 20 2012 102 659 Ul relates to a self-standing multi-layer composite bag for food, comprising a bag body, a mouthpiece and a bag bottom, wherein the mouthpiece is attached to one end of the bag body, the bag bottom is attached to the other end of the bag, and both the bag body and the bag bottom both use a composite structure.

[0010] EP 0 569 196 A1 and US 5 419 967 disclose that by adding methacrylate / unsaturated acid and / or vinylamide copolymers, poly(vinyl alcohol) can be melt processed and coextruded with structural polymers such as poly(ethylene terephthalate) to form multilayer films and articles with good adhesion between the components and good barrier properties.

[0011] EP 0 934 160 B1 relates to a laminated packaging material comprising a layer of paper or cardboard and outer liquid-tight plastic coatings on both sides of the paper or cardboard web. To facilitate material recycling after use of the laminated packaging material, the packaging material is provided with layers of water-soluble polymer between the paper or cardboard layer and each respective outer plastic coating, the layers serving as an adhesive or binder.

[0012] EP 3 885 095 A1 concerns the use of mixtures of water and essential oil for separating multilayer composites for the sorted recycling of polymer or metal foils.

[0013] US 2018 0369859 A1 relates to films that include a water-soluble layer and a vapor-deposited organic coating. The films exhibit improved barrier properties.

[0014] US 2019 0366591 A1 relates to a process for recycling a first polymer from a multi-component polymer product.

[0015] US 2020 0055650 A1 relates to films comprising a water-soluble polymer material and a vapor-deposited inorganic coating.

[0016] US 2020 0199313 A1 relates to water-soluble films made of copolymers of butenediol and vinyl alcohol, wherein the films have improved barrier properties (such as low transmission rates for oxygen and water vapor) and good solubility.

[0017] WO 2000 / 077082 A1 relates to a process for separating plastic mixtures, with a polyolefinic plastic fraction or a plastic mixture as starting material, in which the starting material is brought into contact with a solvent and the temperature of the solvent-plastic mixture is adjusted so that a solution with at least one dissolved polymer type is formed, wherein the dissolved polymer type is precipitated from the solution under shear in order to separate the polymer type from other components of the solution.

[0018] WO 2005 / 118691 A2 relates to a process for the recycling of polyamides from waste, wherein the waste is mixed with ester solvent and the mixture is heated to a temperature above the melting temperature of the polyolefins contained therein to form a composition containing dissolved polyamide polymer and a separate immiscible liquid polyolefin phase.

[0019] WO 2020 / 136674 A1 relates to a recyclable laminate comprising a first layer and a second layer, each layer being a polyolefin layer having a thickness in the range of 12-100 μm; and an intermediate layer having a thickness in the range of 10-35 μm sandwiched between the first polyolefin layer and the second polyolefin layer, the intermediate layer being a metallized polyolefin film having alcohol-based polymer barrier resins therein.

[0020] WO 2021 / 255544 A1 relates to release liners that can be included in various adhesive products. A first release layer is a layer of a composition comprising a) a polymer material having at least one hydrogen atom covalently bonded to an oxygen atom, a nitrogen atom, or a sulfur atom; and b) a silicone polyether comprising at least one of polyoxoethylene units or polyoxopropylene units. A second release layer comprises a substrate and a coating of the above composition disposed on a major surface of the substrate. The release liner composition can advantageously be dissolved and optionally recycled.

[0021] WO 20222 / 46173A1 discloses a recyclable laminate film structure comprising a release coating. The release coating facilitates the separation of a selected polymer film during recycling processing by selecting the polymer of the coating composition to have specific Hansen solubility parameters such that the laminate structure delaminates at the coating layer, leaving clean pieces of the selected polymer film. In certain embodiments, the release coating is a barrier coating, for example, an oxygen barrier coating.

[0022] However, the suitability of the known multilayer films for use in a circular economy is hardly possible or at least in need of improvement.

[0023] One object of the invention was therefore to adapt and improve the design of multilayer films with a view to a circular economy.

[0024] This problem is solved by the subject matter of the patent claims.

[0025] It has been surprisingly discovered that water-soluble polymers, particularly butenediol-vinyl alcohol copolymer (BVOH) or polyvinyl alcohol (PVOH), can act as release layers or predetermined breaking points in multilayer films. The use of biodegradable and environmentally safe water-soluble polymers is a priority in this regard.

[0026] Furthermore, it was found that the application properties of the final product are not significantly impaired by the introduction of at least one release layer or predetermined breaking point based on a water-soluble polymer, or can be otherwise compensated for using methods familiar to the person skilled in the art. In the spirit of a circular economy, the plastic film according to the invention exhibits good recyclability.

[0027] A first aspect of the invention relates to a plastic film which (a) a layer (a) containing or based on polyolefin; (b) optionally a layer (b) containing or based on functionalized polyolefin; (c) optionally a layer (c) based on water-soluble polymer, preferably butenediol-vinyl alcohol copolymers (BVOH) and / or polyvinyl alcohols (PVOH); (d) a layer (d) containing or based on polyamide and / or polyester; (e) optionally a layer (e) based on water-soluble polymer, preferably butenediol-vinyl alcohol copolymers (BVOH) and / or polyvinyl alcohols (PVOH); (f) optionally a layer (f) containing or based on functionalized polyolefin; and (g) optionally a layer (g) which contains or is based on polyolefin; comprises or consists of; wherein the plastic film comprises at least one layer which contains or is based on water-soluble polymer, preferably butenediol-vinyl alcohol copolymer (BVOH).

[0028] Layers (a) and (d) of the plastic film according to the invention are necessarily present. Layers (b), (c), (e), (f), and (g) are each independently optional. Preferably, those present are arranged in alphabetical order.

[0029] In preferred embodiments of the plastic film according to the invention, at least one of the layers (a) to (g) contains water-soluble polymer, optionally in a mixture with non-water-soluble polymer, preferably polyolefin, functionalized polyolefin, polyamide and / or polyester. The presence of the water-soluble polymer impairs the functioning of the inventive The water-soluble polymer content in at least one of the layers (a) to (g) contributes significantly to the formation of a "predetermined breaking point" and the separation of individual components of the plastic film from one another.

[0030] In preferred embodiments of the plastic film according to the invention, the layer (c) and, optionally, layer (e) on a water-soluble polymer. Layer (c) and any additional layer (e) do not significantly impair the functionality of the plastic film according to the invention when used as intended, e.g., as a release film with release properties. However, when the plastic film according to the invention is subjected to processes for the recovery of used raw materials (recycling), layer (c) and any additional layer (e) contribute significantly to ensuring that individual components of the plastic film can be separated from one another.

[0031] In preferred embodiments, the plastic film according to the invention comprises a layer (a) which contains or is based on polyolefin; a layer (c) which is based on a water-soluble polymer; and a layer (d) which contains or is based on polyamide and / or polyester. Layer (c) is arranged between layer (a) and layer (d). When used as intended, e.g., as a release film with release properties, the release properties of the release film are not significantly impaired by the presence of layer (c). After intended use, when the release film with release properties is no longer required and can be properly disposed of, layer (c), due to its water solubility, enables the material of layer (a) to be separated from the material of layer (d) and subsequently recycled, in particular from the material of layers (a) and (d), which may be present in pure form.The plastic film according to the invention, when treated in a water bath, optionally at elevated temperature and after a certain exposure time, is cleavable along layer (c) into the two materials adjacent to layer (c), ie into the material of layer (a) and the material of layer (a). (d), if necessary together with further layers with which layer (a) or layer (d) may be present in combination.

[0032] In other preferred embodiments, the plastic film according to the invention comprises at least one layer which contains or is based on a non-water-soluble polymer, preferably polyolefin, functionalized polyolefin, polyamide and / or polyester, in a mixture with a water-soluble polymer. In this case, too, when used as intended, e.g., as a release film, the release properties of the release film are not significantly impaired by the presence of the water-soluble polymer. After intended use, when the release film with release properties is no longer required and can be disposed of properly, The water-soluble polymer in the layer, due to its water solubility, enables the formation of a predetermined breaking point. The plastic film according to the invention can then be split along the layer into the two materials adjacent to the layer when treated in a water bath, optionally at elevated temperature and after a certain exposure time.

[0033] Unless expressly stated otherwise, all percentages are by weight. Unless expressly stated otherwise, all percentages refer to the total weight of the plastic film according to the invention.

[0034] For the purposes of this description, a layer is "based" on a particular material if that material is the main component of that layer. The weight fraction of the material need not necessarily exceed 50% by weight of the total weight of the respective layer, but this is preferably the case. Typically, a layer is "based" on a particular material if that material makes up at least 70% by weight, more preferably at least 80% by weight, and even more preferably at least 90% by weight of that layer, in each case based on the total weight of the respective layer.

[0035] For the purposes of this description, "water-soluble" means that the material detaches when the composite (the laminate) is placed in a water bath for a sufficient period of time, e.g., 30 minutes, preferably with stirring, and optionally at an elevated temperature, e.g., 60°C. The water bath may contain conventional additives, such as surfactants. Similarly, for the purposes of this description, "insoluble in water" means that the material does not detach under the conditions mentioned above.

[0036] Whether a polymer is water-soluble or water-insoluble within the meaning of the invention is preferably determined by a measurement method. The water solubility of polymers is preferably determined according to OECD Guideline 105 as amended on July 27, 1995. Alternatively, OECD Guideline 120 as amended on January 21, 2000, may be used. The water solubility of polymers is determined according to Commission Regulation (EC) No. 440 / 2008 of May 30, 2008, laying down test methods pursuant to Regulation (EC) No. 1907 / 2006 of the European Parliament and of the Council concerning the Registration, Evaluation, Authorization and Restriction of Chemicals (REACH), as amended on March 4, 2016, using Method A.6 "Water Solubility," which corresponds to OECD Test Guideline (TG) 105 (1995).

[0029] Preferably, "water-soluble" means a solubility in pure water at 20.0±0.5°C of at least 2.0 g / L; correspondingly, "water-insoluble" preferably means a solubility of less than 2.0 g / L. This solubility limit was also chosen by the European Chemicals Agency (ECHA) (see Opinion on an Annex XV dossier proposing restrictions on intentionally-added microplastics of June 11, 2020).

[0037] Preferably, the water-soluble polymers according to the invention have a water solubility under the conditions mentioned which is significantly above the limit value of 2.0 g / L, preferably at least 5.0 g / L; more preferably at least 10 g / L, even more preferably at least 15 g / L, most preferably at least 20 g / L, and especially at least 25 g / L.

[0038] Water-soluble polymers according to the invention are preferably virtually unlimitedly miscible with water, particularly at elevated temperatures, but then form gels above a certain concentration, the viscosity of which may increase significantly.

[0039] In preferred embodiments, the water-soluble polymers of the invention exhibit a solubility such that, at a concentration of 10 wt.% in pure water, the polymer is virtually completely dissolved after at most 40 minutes (i.e., upon reaching 60°C), preferably after at most 30 minutes (i.e., upon reaching 50°C), with stirring and continuous heating from 20°C to 85°C at a heating rate of 1°C / min. Products under the name Nichigo G-Polymer®, for example, meet this requirement.

[0040] In preferred embodiments, the water-soluble polymers according to the invention exhibit a solubility such that, at a concentration of 5.0 wt.% in pure water with stirring at 20°C, the polymer is virtually completely dissolved after at most 2 hours. This requirement is met, for example, by the product known as Nichigo G-Polymer® AZF8035W.

[0041] In preferred embodiments, the water-soluble polymers of the invention exhibit a solubility such that, at a concentration of 5.0 wt.% in pure water with stirring at a temperature of 70°C, the polymer is virtually completely dissolved after 1 hour at the latest. This requirement is met, for example, by the products under the names Nichigo G-Polymer® AZF8035W, OKS-1001, and OKS 8074P.

[0042] In preferred embodiments, the water-soluble polymers of the invention exhibit a solubility such that, at a concentration of 5.0 wt.% in pure water with stirring at a temperature of 90°C, the polymer is virtually completely dissolved after 1 hour at the latest. This requirement is met, for example, by the products under the names Nichigo G-Polymer® AZF8035W, OKS-1001, and OKS 8074P.

[0043] In preferred embodiments, a film with a layer thickness of 200 μm consisting of the pure water-soluble polymer dissolves completely in a sufficient amount of water within 6 minutes at 25 °C and with stirring. These requirements are met, for example, by Mowiflex® types CI 7, C30, C600, C130T, and C500T.

[0044] Under the conditions mentioned, the non-water-soluble polymers according to the invention preferably have a water solubility which is significantly below the limit of 2.0 g / L (2000 mg / L), preferably at most 1000 mg / L; more preferably at most 500 mg / L, even more preferably at most 100 mg / L, most preferably at most 50 mg / L, and in particular at most 10 mg / L.

[0045] For the purposes of the invention, a polymer is preferably considered to be water-soluble if at least 50 g of this polymer can be homogenized in one liter of pure water at 25°C.

[0046] For the purposes of the invention, and regardless of numerically quantified solubility (e.g., in g / L or mg / L), polyolefins, functionalized polyolefins, polyesters, and polyamides are preferably considered non-water-soluble polymers, and butenediol-vinyl alcohol copolymers (BVOH) and polyvinyl alcohols (PVOH) are considered water-soluble polymers. Suitable water-soluble polymers for the purposes of the invention are commercially available, for example, under the names Nichigo G-Polymer® and Mowiflex®.

[0047] If the water-soluble polymer according to the invention is a butenediol-vinyl alcohol copolymer (BVOH) or a polyvinyl alcohol (PVOH), vinyl acetate is typically used as a (co)monomer in the polymerization, and its ester groups are subsequently at least partially saponified. According to the invention, the degree of saponification is preferably, independently of one another, at least 80 mol%, more preferably at least 85 mol%, even more preferably at least 90 mol%, most preferably at least 95 mol%, and in particular approximately 100 mol%. It may be preferred if the degree of saponification is not complete, for example, at most 99 mol%, or at most 98 mol%, or at most 97 mol%.

[0048] Butenediol-vinyl alcohol copolymers (BVOH) preferred according to the invention have a melt flow index (MFI) at 210°C and 2160 g in the range of 0.5 to 35 g / 10 min, more preferably in the range of 1.0 to 30 g / 10 min, even more preferably in the range of 1.5 to 20 g / 10 min, most preferably in the range of 2.0 to 10 g / 10 min, and in particular in the range of 2.5 to 5.0 g / 10 min.

[0049] Polyvinyl alcohols (PVOH) preferred according to the invention have a melt flow index at 190°C and 2160 g in the range of 0.5 to 50 g / 10 min, more preferably in the range of 1.0 to 45 g / 10 min, even more preferably in the range of 1.5 to 40 g / 10 min, most preferably in the range of 2.0 to 35 g / 10 min, and in particular in the range of 2.5 to 30 g / 10 min.

[0050] According to the invention, it is possible to use mixtures of several water-soluble polymers, for example several polyvinyl alcohols (PVOH) with different degrees of saponification, several butenediol-vinyl alcohol copolymers (BVOH) with different degrees of saponification, or mixtures of polyvinyl alcohols (PVOH) with butenediol-vinyl alcohol copolymers (BVOH).

[0051] It is possible for the plastic film according to the invention to comprise further layers in addition to the required layers and the optional layers. However, the plastic film according to the invention preferably consists of the required layers and, if appropriate, one or more of the optional layers.

[0052] The plastic film according to the invention comprises at least one layer which contains or is based on water-soluble polymer, wherein the plastic film, when treated in a water bath, optionally at elevated temperature and after a sufficient exposure time, is cleavable along this layer.

[0053] The plastic film according to the invention preferably has a total layer thickness in the range from 10 to 250 pm.

[0054] The plastic film preferably has a total layer thickness of at least 20 pm, more preferably at least 25 pm, even more preferably at least 30 pm, most preferably at least 35 pm and in particular at least 40 pm.

[0055] The plastic film preferably has a total layer thickness of at most 90 pm, more preferably at most 80 pm, even more preferably at most 70 pm, most preferably at most 60 pm and in particular at most 50 pm.

[0056] In preferred embodiments, the plastic film according to the invention has a symmetrical layer structure.

[0057] Preferably, the plastic film according to the invention is extrudable, preferably coextrudable in one step, more preferably by blown film coextrusion.

[0058] In preferred embodiments, at least one layer of the plastic film according to the invention contains or is based on extrudable, water-soluble polymer.

[0059] Preferably, at least one layer of the plastic film according to the invention contains one or more water-soluble polymers or is based thereon independently selected from (i) fully synthetic water-soluble polymers; (ii) semi-synthetic or natural water-soluble polymers.

[0060] Preferably, the at least one layer of the plastic film according to the invention contains or is based on one or more water-soluble polymers selected from polymers or copolymers of vinyl acetate, vinylpyrrolidone, ethylene oxide, acrylamide, and lactic acid; preferably polymers or copolymers of vinyl acetate.

[0061] In preferred embodiments, at least one layer of the plastic film according to the invention contains or is based on one or more water-soluble polymers selected independently from the group consisting of butenediol-vinyl alcohol copolymer (BVOH), polyvinyl alcohol (PVOH), polyvinyl acetate (PVA), polyvinylpyrrolidone (PVP), polyethylene oxide (PEO), polyacrylamide (PAM), and polylactic acid (PLA).

[0062] Preferably, at least one layer of the plastic film according to the invention contains butenediol-vinyl alcohol copolymer (BVOH) or is based thereon.

[0063] Preferably, at least one layer of the plastic film according to the invention contains or is based on one or more water-soluble polymers with an ethylene group content of at most 10 mol%, more preferably at most 5.0 mol%, even more preferably at most 2.5 mol%, and in particular practically no ethylene groups at all.

[0064] Preferably, at least one layer of the plastic film according to the invention contains or is based on one or more water-soluble polymers with a vinyl ester group content of at most 20 mol%, more preferably at most 15 mol%, even more preferably at most 10 mol%, most preferably at most 5.0 mol%, and in particular at most 2.5 mol%.

[0065] Preferably, at least one layer of the plastic film according to the invention contains or is based on one or more water-soluble polymers with a content of vinyl alcohol groups in the range of 40 to 85 mol%, preferably 50 to 75 mol%.

[0066] Preferably, at least one layer of the plastic film according to the invention contains or is based on one or more water-soluble polymers with a content of butylene groups in the range of 15 to 60 mol%, preferably 25 to 50 mol%.

[0067] Butenediol-vinyl alcohol copolymer (BVOH) is particularly preferred according to the invention because it can be extruded particularly advantageously and can therefore be processed, for example, by blown film coextrusion, while simultaneously exhibiting particularly good water solubility. In this respect, butenediol-vinyl alcohol copolymer (BVOH) is particularly advantageous compared to polyvinyl alcohol (PVOH) and polyvinyl acetate (PVA).

[0068] In preferred embodiments of the plastic film according to the invention, the total content of water-soluble polymer contained in the plastic film, based on the total weight of the plastic film, is at least 0.5 wt.%, more preferably at least 1.0 wt.%, even more preferably at least 2.0 wt.%, most preferably at least 3.0 wt.% and in particular at least 4.0 wt.%.

[0069] Preferably, the total content of water-soluble polymer contained in the plastic film, based on the total weight of the plastic film, is at most 18 wt.%, more preferably at most 16 wt.%, even more preferably at most 14 wt.%, most preferably at most 12 wt.% and in particular at most 10 wt.%.

[0070] Preferably, the total content of water-soluble polymer contained in the plastic film, based on the total weight of the plastic film, is at most 10 wt.%, more preferably at most 9.0 wt.%, even more preferably at most 8.0 wt.%, most preferably at most 7.0 wt.% and in particular at most 6.0 wt.%.

[0071] Preferably, layer (a) contains or is based on one or more polyolefins independently selected from the group consisting of thermoplastic olefin homopolymers; and / or thermoplastic olefin copolymers of α,β-unsaturated olefins having 2 to 10 carbon atoms.

[0072] Layer (a) preferably contains or is based on one or more polyolefins selected independently from the group consisting of polyethylene, polypropylene, polybutylene, polyisobutylene (PI), copolymers and / or mixtures of at least two of the polymers mentioned; preferably polypropylene.

[0073] In preferred embodiments, layer (a) contains, based on the total weight of layer (a), at least 50 wt.% polyolefin, more preferably at least 60 wt.%, even more preferably at least 70 wt.%, most preferably at least 80 wt.% and in particular at least 90 wt.%.

[0074] In these preferred embodiments, layer (a) contains, based on the total weight of layer (a), at most 10 wt.% water-soluble polymer, more preferably 5 wt.%, even more preferably at most 2.5 wt.%, most preferably at most 1.0 wt.%, and in particular practically no water-soluble polymer at all.

[0075] In other preferred embodiments, layer (a) contains a mixture of polyolefin and water-soluble polymer.

[0076] Preferably, the water-soluble polymer is independently selected from the group consisting of butenediol-vinyl alcohol copolymer (BVOH), polyvinyl alcohol (PVOH), polyvinyl acetate (PVA), polyvinylpyrrolidone (PVP), polyethylene oxide (PEO), polyacrylamide (PAM), and polylactic acid (PLA); preferably butenediol-vinyl alcohol copolymer (BVOH).

[0077] Preferably, the content of water-soluble polymer is greater than the content of polyolefin.

[0078] Preferably, the relative weight ratio of water-soluble polymer to polyolefin is in the ratio of 10:1 to 1:10, preferably 8:1 to 1:8, more preferably 6:1 to 1:6, even more preferably 4:1 to 1:4, most preferably 3:1 to 1:3 and in particular 2:1 to 1:2.

[0079] Preferably, the relative weight ratio of water-soluble polymer to polyolefin is in the ratio of 11:1 to 1:2, preferably 10:1 to 1:1, more preferably 9:1 to 2:1, even more preferably 8:1 to 3:1, most preferably 7:1 to 4:1 and especially 6:1 to 5:1.

[0080] Preferably, based on the weight of layer (a), independently of each other - the polyolefin content is in the range of 15±14 wt.%, preferably 15±12 wt.%, more preferably 15±10 wt.%, even more preferably 15±8.0 wt.%, most preferably 15±6.0 wt.%, and in particular 15±4.0 wt.%, and - the content of water-soluble polymer in the range of 85±14 wt%, preferably 85±12 wt%, more preferably 85±10 wt%, even more preferably 85±8.0 wt%, most preferably 85±6.0 wt%, and in particular 85±4.0 wt%.

[0081] In preferred embodiments, layer (a) comprises several layers (ai), (a2), etc.

[0082] In particularly preferred embodiments, layer (a) has at least three layers and comprises layer (ai), layer (a2), and layer (as), with layer (a2) being arranged between layers (ai) and (as). Layers (ai) and (as) are preferably based on the same polyolefin, which preferably differs from the polyolefin on which layer (as) is based.

[0083] In preferred embodiments, the layer (a) or the layer (as) is based on polyolefin, preferably olefin homo- or copolymer, which is preferably selected from the group consisting of polyethylene, polypropylene, polybutylene, polyisobutylene, polyhexene, polyoctene, copolymers and / or mixtures of at least two of the polymers mentioned.

[0084] Preferably, the olefin homo- or copolymer of layer (a) or layer (as) is an ethylene homopolymer or an ethylene copolymer.

[0085] Preferably, the ethylene homo- or copolymer of layer (a) or ply (as) is selected from the group consisting of low density polyethylene (LDPE), linear low density polyethylene (LLDPE), medium density polyethylene (MDPE), and high density polyethylene (HDPE).

[0086] For the purposes of this description, ethylene homopolymers or copolymers are understood to mean ethylene homopolymers based exclusively on ethylene and ethylene copolymers based, in addition to ethylene, on at least one other α,β-unsaturated olefin having 3 to 10 carbon atoms. Preferred ethylene homopolymers or copolymers are polyethylene with highly branched polymer chains and a low density in the range of 0.915 to 0.940 g / cm 3 (LDPE); polyethylene with an average density in the range of 0.926 to 0.940 g / cm 3 (MDPE); polyethylene with weakly branched polymer chains and a high density in the range of 0.945 to 0.97 g / cm 3(HDPE); and linear low-density polyethylene with short branched polymer chains, which may contain, in addition to ethylene as a comonomer, one or more higher α,β-unsaturated olefins such as butylene, hexene, or octene, with a density in the range of 0.915 to 0.94 g / cm 3 (LLDPE).

[0087] Preferably, the polyolefin on which the layer (a) or the ply (as) is based comprises a mixture of an ethylene homo- or copolymer and a propylene homo- or copolymer.

[0088] In preferred embodiments, the polyolefin on which the layer (a) or the layer (as) is based comprises a mixture of 51 to 85 wt.% of an ethylene homo- or copolymer having a density in the range of 0.91 to 0.97 g / cm 3 ; and 15 to 49% by weight of a propylene homo- or copolymer; each based on the total weight of the mixture.

[0089] For the purposes of this description, propylene homopolymers or copolymers are understood to mean propylene homopolymers based exclusively on propylene and propylene copolymers based, in addition to propylene, on at least one other α,β-unsaturated olefin having 2 to 10 carbon atoms. Preferred propylene homopolymers are isotactic propylene homopolymers, preferably with a melting point in the range of 140 to 170°C. Preferred propylene copolymers are copolymers of propylene and ethylene, with the proportion of ethylene preferably being at most 20% by weight, based on the total weight of the propylene copolymer.

[0090] In preferred embodiments, the layer (a) or the layer (a2) consists of LDPE and a propylene homo- or copolymer.

[0091] In other preferred embodiments, the layer (a) or the layer (a2) consists of LLDPE and a propylene homo- or copolymer.

[0092] Preferably, the layer (a) or the layers (ai) and (as) are each independently based on - polyolefin, wherein the polyolefin is selected from the group consisting of olefin homo- or copolymers of α,β-unsaturated olefins having 2 to 10 carbon atoms; or - an ethylene-vinyl acetate copolymer.

[0093] In preferred embodiments, layer (a) or layers (ai) and (as) are each independently based on an ethylene-vinyl acetate copolymer.

[0094] In other preferred embodiments, layer (a) or layers (ai) and (as) are each independently based on polyolefin, wherein the polyolefin is selected from the group consisting of olefin homo- or copolymers of α,β-unsaturated olefins having 2 to 10 carbon atoms.

[0095] In these preferred embodiments, the polyolefin of layer (a) or of layers (ai) and (as) is preferably selected, each independently of one another, from the group consisting of polyethylene, polypropylene, polybutylene, polyisobutylene, polyhexene, polyoctene, copolymers and / or mixtures of at least two of the polymers mentioned.

[0096] Preferably, the olefin homopolymer or copolymer of layer (a) or of layers (ai) and (as) is each independently an ethylene homopolymer or an ethylene copolymer.

[0097] Preferably, the ethylene homo- or copolymer of layer (a) or of layers (ai) and (as) is each independently selected from the group consisting of low density polyethylene (LDPE), linear low density polyethylene (LLDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), and their blends.

[0098] Preferably, layer (a) or layers (ai) and (as) each independently consist of a mixture of two ethylene homopolymers or copolymers, preferably a mixture of LDPE with LLDPE, MDPE, or HDPE. The proportion of LDPE is preferably in the range of 10 to 85 wt.%, and the proportion of the second ethylene homopolymer or copolymer is preferably in the range of 15 to 90 wt.%.

[0099] Layer (a) preferably has a layer thickness in the range from 0.5 to 100 pm, preferably 0.5 to 25 pm.

[0100] In preferred embodiments of the plastic film according to the invention, layer (a) has a layer thickness of at least 4.0 pm, more preferably at least 8.0 pm, even more preferably at least 12 pm, most preferably at least 16 pm and in particular at least 20 pm.

[0101] In preferred embodiments of the plastic film according to the invention, the layer (a) a layer thickness of at most 22 pm, more preferably at most 19 pm, even more preferably at most 16 pm, most preferably at most 13 pm and in particular at most 10 pm.

[0102] Preferably, layer (a) does not contain a functionalized polyolefin. For the purposes of this description, "functionalized polyolefin" refers to a copolymer based on polyolefin and formed by copolymerization, preferably graft copolymerization, of the polyolefin with suitable monomers. Suitable monomers are preferably polar monomers such as acids or acid anhydrides to introduce polar functionalities into the polyolefin. Preferably, functionalized polyolefin is an anhydride-modified polyolefin or an acid-modified polyolefin.

[0103] In preferred embodiments of the plastic film according to the invention, the layer contains (b) anhydride-modified polyolefin or acid-modified polyolefin or based thereon.

[0104] Preferably, layer (b) contains or is based on maleic anhydride-modified polyolefin.

[0105] In addition to the functionalized polyolefin, layer (b) may optionally contain further polymers, preferably those polymers which are contained in one of the layers adjacent to layer (b), i.e. the same polyolefin which is contained in layer (a) and / or the same water-soluble polymer which is contained in the optionally present layer (c).

[0106] In preferred embodiments of the plastic film according to the invention, layer (b) contains, based on the total weight of layer (b), at least 10 wt.% functionalized polyolefin, more preferably at least 15 wt.%, even more preferably at least 20 wt.%, most preferably at least 25 wt.% and in particular at least 30 wt.%.

[0107] In preferred embodiments of the plastic film according to the invention, layer (b) contains, in addition to the functionalized polyolefin, further polymers, preferably the same (non-functionalized) polyolefin which is contained in layer (a).

[0108] In these preferred embodiments, layer (b) contains, based on the total weight of layer (b), at least 30 wt.% polyolefin and / or functionalized polyolefin, more preferably at least 40 wt.%, even more preferably at least 50 wt.%, most preferably at least 60 wt.% and in particular at least 70 wt.%.

[0109] In these preferred embodiments, layer (b) contains, based on the total weight of layer (b), at most 10 wt.% water-soluble polymer, more preferably 5 wt.%, even more preferably at most 2.5 wt.%, most preferably at most 1.0 wt.%, and in particular practically no water-soluble polymer at all.

[0110] In these preferred embodiments, the plastic film according to the invention preferably contains layer (c).

[0111] In other preferred embodiments of the plastic film according to the invention, layer (b) contains, in addition to the functionalized polyolefin, further polymers, preferably the same water-soluble polymer which is contained in layer (c).

[0112] In these preferred embodiments, layer (b) contains, based on the total weight of layer (b), at least 5.0 wt.% functionalized polyolefin, more preferably at least 7.5 wt.%, even more preferably at least 10 wt.%, most preferably at least 12.5 wt.% and in particular at least 15 wt.%.

[0113] In these preferred embodiments, layer (b) contains, based on the total weight of layer (b), at least 45 wt% water-soluble polymer, more preferably at least 55 wt%, even more preferably at least 65 wt%, most preferably at least 75 wt% and in particular at least 85 wt%.

[0114] In these preferred embodiments, based on the weight of layer (b), independently of each other - the content of functionalized polyolefin in the range of 15±14 wt.%, preferably 15±12 wt.%, more preferably 15±10 wt.%, even more preferably 15±8.0 wt.%, most preferably 15±6.0 wt.%, and in particular 15±4.0 wt.%, and - the content of water-soluble polymer in the range of 85±14 wt%, preferably 85±12 wt%, more preferably 85±10 wt%, even more preferably 85±8.0 wt%, most preferably 85±6.0 wt%, and in particular 85±4.0 wt%.

[0115] Preferably, the content of water-soluble polymer is greater than the content of functionalized polyolefin.

[0116] In these preferred embodiments, the relative weight ratio of water-soluble polymer to functionalized polyolefin is in the ratio of 10:1 to 1:10, preferably 8:1 to 1:8, more preferably 6:1 to 1:6, even more preferably 4:1 to 1:4, most preferably 3:1 to 1:3 and especially 2:1 to 1:2.

[0117] Preferably, the relative weight ratio of water-soluble polymer to functionalized polyolefin is in the ratio of 11:1 to 1:2, preferably 10:1 to 1:1, more preferably 9:1 to 2:1, even more preferably 8:1 to 3:1, most preferably 7:1 to 4:1 and especially 6:1 to 5:1.

[0118] In these preferred embodiments, layer (b) contains, based on the total weight of layer (b), at most 10 wt.% polyolefin, more preferably 5 wt.%, even more preferably at most 2.5 wt.%, most preferably at most 1.0 wt.%, and in particular practically no (unfunctionalized) polyolefin at all.

[0119] In these preferred embodiments, the plastic film according to the invention preferably does not contain layer (c).

[0120] Layer (b) preferably has a layer thickness in the range from 0.5 to 25 pm, preferably 0.5 to 10 pm.

[0121] In preferred embodiments of the plastic film according to the invention, layer (b) has a layer thickness of at least 1.0 pm, more preferably at least 2.0 pm, even more preferably at least 3.0 pm, most preferably at least 4.0 pm and in particular at least 5.0 pm.

[0122] In preferred embodiments of the plastic film according to the invention, the layer (b) a layer thickness of at most 9.0 pm, more preferably at most 8.0 pm, even more preferably at most 7.0 pm, most preferably at most 6.0 pm and in particular at most 5.0 pm.

[0123] In preferred embodiments of the plastic film according to the invention, the layer (c) on extrudable, water-soluble polymer.

[0124] Preferably, layer (c) is based on one or more water-soluble polymers independently selected from (i) fully synthetic water-soluble polymers; (ii) semi-synthetic or natural water-soluble polymers.

[0125] In preferred embodiments of the plastic film according to the invention, layer (c) is based on one or more water-soluble polymers selected from polymers or copolymers of vinyl acetate, vinylpyrrolidone, ethylene oxide, acrylamide, and lactic acid; preferably polymers or copolymers of vinyl acetate.

[0126] In preferred embodiments of the plastic film according to the invention, layer (c) is based on one or more water-soluble polymers independently selected from the group consisting of butenediol-vinyl alcohol copolymer (BVOH), polyvinyl alcohol (PVOH), polyvinyl acetate (PVA), polyvinylpyrrolidone (PVP), polyethylene oxide (PEO), polyacrylamide (PAM), and polylactic acid (PLA).

[0127] Preferably, layer (c) is based on butenediol-vinyl alcohol copolymer (BVOH).

[0128] Preferably, layer (c) is based on one or more water-soluble polymers having an ethylene group content of at most 10 mol%, more preferably at most 5.0 mol%, even more preferably at most 2.5 mol%, and in particular practically no ethylene groups at all.

[0129] Preferably, layer (c) is based on one or more water-soluble polymers having a vinyl ester group content of at most 20 mol%, more preferably at most 15 mol%, even more preferably at most 10 mol%, most preferably at most 5.0 mol%, and in particular at most 2.5 mol%.

[0130] Preferably, layer (c) is based on one or more water-soluble polymers having a vinyl alcohol group content in the range of 40 to 85 mol%, preferably 50 to 75 mol%.

[0131] Preferably, layer (c) is based on one or more water-soluble polymers having a butylene group content in the range of 15 to 60 mol%, preferably 25 to 50 mol%.

[0132] In preferred embodiments of the plastic film according to the invention, layer (c) contains, based on the total weight of layer (c), at least 50% by weight of water-soluble polymer, more preferably at least 60% by weight, even more preferably at least 70% by weight, most preferably at least 80% by weight and in particular at least 90% by weight.

[0133] Preferably, layer (c) contains, based on the total weight of layer (c), at most 10 wt.% of non-water-soluble polymer, preferably polyolefin and / or functionalized polyolefin, more preferably 5 wt.%, even more preferably at most 2.5 wt.%, most preferably at most 1.0 wt.%, and in particular practically no polyolefin and / or functionalized polyolefin, preferably no non-water-soluble polymer at all.

[0134] Preferably, layer (c) has a layer thickness in the range of 0.5 to 100 pm, preferably 0.5 to 25 pm.

[0135] In preferred embodiments of the plastic film according to the invention, layer (c) has a layer thickness of at least 0.5 pm, more preferably at least 0.75 pm, even more preferably at least 1.0 pm, most preferably at least 1.25 pm and in particular at least 1.5 pm.

[0136] In preferred embodiments of the plastic film according to the invention, layer (c) has a layer thickness of at most 9.0 pm, more preferably at most 8.0 pm, even more preferably at most 7.0 pm, most preferably at most 6.0 pm and in particular at most 5.0 pm.

[0137] In preferred embodiments of the plastic film according to the invention, the layer (c) a layer thickness of at most 4.0 pm, more preferably at most 3.0 pm, even more preferably at most 2.5 pm, most preferably at most 2.0 pm and in particular at most 1.75 pm.

[0138] The layer (d) contains or is based on polyamide and / or polyester, preferably polyamide.

[0139] Suitable polyamides are thermoplastic, aliphatic, semi-aromatic, or aromatic polyamide homopolymers or copolymers. Such polyamides are polyamides made from diamines, such as aliphatic diamines with 2-10 carbon atoms, in particular hexamethylenediamine, or aromatic diamines with 6-10 carbon atoms, in particular p-phenylenediamine, and dicarboxylic acids, such as aliphatic or aromatic dicarboxylic acids with 6-14 carbon atoms, such as adipic acid, terephthalic acid, or isoterephthalic acid. Furthermore, the polyamides can be produced from lactams with 4-10 carbon atoms, such as 8-caprolactam. Particularly suitable polyamides include PA 6, PA 12, PA 66, PA 61, PA 6T, and / or mixtures of at least two of the polyamides mentioned.

[0140] Suitable polyesters are thermoplastic, aliphatic, semi-aromatic, or aromatic polyester homopolymers or copolymers. Such polyesters are derived from polyols such as ethylene glycol or 1,4-butanediol and dicarboxylic acids or dicarboxylic acid derivatives such as adipic acid and / or terephthalic acid. According to the invention, polycarbonates (PC) can also be used as polyesters. Polybutylene adipate (PBA), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), or the corresponding copolymers are preferred.

[0141] In preferred embodiments of the plastic film according to the invention, the layer contains (d) polyamide or based thereon.

[0142] In preferred embodiments of the plastic film according to the invention, layer (d) contains, based on the total weight of layer (d), at least 50 wt.% polyamide and / or polyester, more preferably at least 60 wt.%, even more preferably at least 70 wt.%, most preferably at least 80 wt.% and in particular at least 90 wt.%.

[0143] Preferably, layer (d) contains, based on the total weight of layer (d), at most 10 wt.% water-soluble polymer, more preferably 5 wt.%, even more preferably at most 2.5 wt.%, most preferably at most 1.0 wt.%, and in particular practically no water-soluble polymer at all.

[0144] In preferred embodiments of the plastic film according to the invention, layer (d) contains a mixture of (i) polyamide and / or polyester and (ii) water-soluble polymer.

[0145] Preferably, the water-soluble polymer is independently selected from the group consisting of butenediol-vinyl alcohol copolymer (BVOH), polyvinyl alcohol (PVOH), polyvinyl acetate (PVA), polyvinylpyrrolidone (PVP), polyethylene oxide (PEO), polyacrylamide (PAM), and polylactic acid (PLA), preferably butenediol-vinyl alcohol copolymer (BVOH).

[0146] Preferably, the content of water-soluble polymer is greater than the total content of polyamide and / or polyester.

[0147] Preferably, the relative weight ratio of water-soluble polymer to the total amount of polyamide and / or polyester is in the ratio of 10:1 to 1:10, preferably 8:1 to 1:8, more preferably 6:1 to 1:6, even more preferably 4:1 to 1:4, most preferably 3:1 to 1:3 and in particular 2:1 to 1:2.

[0148] Preferably, the relative weight ratio of water-soluble polymer to the total amount of polyamide and / or polyester is in the ratio of 11:1 to 1:2, preferably 10:1 to 1:1, more preferably 9:1 to 2:1, even more preferably 8:1 to 3:1, most preferably 7:1 to 4:1 and in particular 6:1 to 5:1.

[0149] Preferably, based on the weight of the layer (d) independently of each other - the content of polyamide and / or polyester in the range of 15±14 wt.%, preferably 15±12 wt.%, more preferably 15±10 wt.%, even more preferably 15±8.0 wt.%, most preferably 15±6.0 wt.%, and in particular 15±4.0 wt.%, and - the content of water-soluble polymer in the range of 85±14 wt%, preferably 85±12 wt%, more preferably 85±10 wt%, even more preferably 85±8.0 wt%, most preferably 85±6.0 wt%, and in particular 85±4.0 wt%.

[0150] Preferably, layer (d) has a layer thickness in the range from 0.5 to 100 pm, preferably 0.5 to 25 pm.

[0151] In preferred embodiments of the plastic film according to the invention, the layer (d) a layer thickness of at least 1.0 pm, more preferably at least 2.0 pm, even more preferably at least 3.0 pm, most preferably at least 4.0 pm and in particular at least 5.0 pm.

[0152] Preferably, layer (d) has a layer thickness of at most 22 pm, more preferably at most 19 pm, even more preferably at most 16 pm, most preferably at most 13 pm and in particular at most 10 pm.

[0153] In preferred embodiments of the plastic film according to the invention, the layer (e) on extrudable, water-soluble polymer.

[0154] Preferably, the layer (e) is based on one or more water-soluble polymers independently selected from (i) fully synthetic water-soluble polymers; (ii) semi-synthetic or natural water-soluble polymers.

[0155] In preferred embodiments of the plastic film according to the invention, layer (e) is based on one or more water-soluble polymers selected from polymers or copolymers of vinyl acetate, vinylpyrrolidone, ethylene oxide, acrylamide, and lactic acid; preferably polymers or copolymers of vinyl acetate.

[0156] In preferred embodiments of the plastic film according to the invention, the layer (e) is based on one or more water-soluble polymers independently selected from the group consisting of butenediol-vinyl alcohol copolymer (BVOH), polyvinyl alcohol (PVOH), polyvinyl acetate (PVA), polyvinylpyrrolidone (PVP), polyethylene oxide (PEO), polyacrylamide (PAM), and polylactic acid (PLA).

[0157] Preferably, layer (e) is based on butenediol-vinyl alcohol copolymer (BVOH).

[0158] Preferably, the layer (e) is based on one or more water-soluble polymers having an ethylene group content of at most 10 mol%, more preferably at most 5.0 mol%, even more preferably at most 2.5 mol%, and in particular practically no ethylene groups at all.

[0159] Preferably, layer (e) is based on one or more water-soluble polymers having a vinyl ester group content of at most 20 mol%, more preferably at most 15 mol%, even more preferably at most 10 mol%, most preferably at most 5.0 mol%, and in particular at most 2.5 mol%.

[0160] Preferably, layer (e) is based on one or more water-soluble polymers having a content of vinyl alcohol groups in the range of 40 to 85 mol%, preferably 50 to 75 mol%.

[0161] Preferably, layer (e) is based on one or more water-soluble polymers having a butylene group content in the range of 15 to 60 mol%, preferably 25 to 50 mol%.

[0162] In preferred embodiments of the plastic film according to the invention, layer (e) contains, based on the total weight of layer (e), at least 50 wt.% water-soluble polymer, more preferably at least 60 wt.%, even more preferably at least 70 wt.%, most preferably at least 80 wt.% and in particular at least 90 wt.%.

[0163] Preferably, layer (e), based on the total weight of layer (e), contains at most 10 wt.% of non-water-soluble polymer, preferably polyolefin and / or functionalized polyolefin, more preferably 5 wt.%, even more preferably at most 2.5 wt.%, most preferably at most 1.0 wt.%, and in particular practically no polyolefin and / or functionalized polyolefin, preferably no non-water-soluble polymer at all.

[0164] Preferably, layer (e) has a layer thickness in the range of 0.5 to 100 µm, preferably 0.5 to 25 µm.

[0165] In preferred embodiments of the plastic film according to the invention, layer (e) has a layer thickness of at least 0.5 µm, more preferably at least 0.75 µm, even more preferably at least 1.0 µm, most preferably at least 1.25 µm and in particular at least 1.5 µm.

[0166] In preferred embodiments of the plastic film according to the invention, layer (e) has a layer thickness of at most 9.0 µm, more preferably at most 8.0 µm, even more preferably at most 7.0 µm, most preferably at most 6.0 µm and in particular at most 5.0 µm.

[0167] In preferred embodiments of the plastic film according to the invention, layer (e) has a layer thickness of at most 4.0 µm, more preferably at most 3.0 µm, even more preferably at most 2.5 µm, most preferably at most 2.0 µm and in particular at most 1.75 µm.

[0168] In preferred embodiments of the plastic film according to the invention, the layer (e) has the same layer structure as layer (c).

[0169] In other preferred embodiments of the plastic film according to the invention, layer (e) has a different layer structure than layer (c).

[0170] In preferred embodiments of the plastic film according to the invention, the layer contains (f) anhydride-modified polyolefin or acid-modified polyolefin or based thereon.

[0171] Preferably, layer (f) contains or is based on maleic anhydride-modified polyolefin.

[0172] In addition to the functionalized polyolefin, layer (f) may optionally contain further polymers, preferably those polymers which are contained in one of the layers adjacent to layer (f), i.e. the same polyolefin which is contained in layer (g) and / or the same water-soluble polymer which is contained in layer (e).

[0173] In preferred embodiments of the plastic film according to the invention, layer (f), based on the total weight of layer (f), contains at least 10 wt.% functionalized polyolefin, more preferably at least 15 wt.%, even more preferably at least 20 wt.%, most preferably at least 25 wt.% and in particular at least 30 wt.%.

[0174] In preferred embodiments of the plastic film according to the invention, layer (f) contains, in addition to the functionalized polyolefin, further polymers, preferably the same (non-functionalized) polyolefin which is contained in layer (g).

[0175] In these preferred embodiments, the layer (f) contains, based on the total weight of the layer (f), at least 30 wt.% polyolefin and / or functionalized polyolefin, more preferably at least 40 wt%, even more preferably at least 50 wt%, most preferably at least 60 wt% and especially at least 70 wt%.

[0176] In these preferred embodiments, layer (f) contains, based on the total weight of layer (f), at most 10 wt.% water-soluble polymer, more preferably 5 wt.%, even more preferably at most 2.5 wt.%, most preferably at most 1.0 wt.%, and in particular practically no water-soluble polymer at all.

[0177] In these preferred embodiments, the plastic film according to the invention preferably contains layer (e).

[0178] In other preferred embodiments of the plastic film according to the invention, layer (f) contains, in addition to the functionalized polyolefin, further polymers, preferably the same water-soluble polymer which is contained in layer (e).

[0179] In these preferred embodiments, layer (f) contains, based on the total weight of layer (f), at least 5.0 wt.% functionalized polyolefin, more preferably at least 7.5 wt.%, even more preferably at least 10 wt.%, most preferably at least 12.5 wt.% and in particular at least 15 wt.%.

[0180] In these preferred embodiments, layer (f) contains, based on the total weight of layer (f), at least 45 wt% water-soluble polymer, more preferably at least 55 wt%, even more preferably at least 65 wt%, most preferably at least 75 wt% and in particular at least 85 wt%.

[0181] In these preferred embodiments, based on the weight of the layer (f), independently of each other - the content of functionalized polyolefin in the range of 15±14 wt.%, preferably 15±12 wt.%, more preferably 15±10 wt.%, even more preferably 15±8.0 wt.%, most preferably 15±6.0 wt.%, and in particular 15±4.0 wt.%, and - the content of water-soluble polymer in the range of 85±14 wt%, preferably 85±12 wt%, more preferably 85±10 wt%, even more preferably 85±8.0 wt%, most preferably 85±6.0 wt%, and in particular 85±4.0 wt%.

[0182] Preferably, the content of water-soluble polymer is greater than the content of functionalized polyolefin.

[0183] In these preferred embodiments, the relative weight ratio of water-soluble polymer to functionalized polyolefin is in the ratio of 10:1 to 1:10, preferably 8:1 to 1:8, more preferably 6:1 to 1:6, even more preferably 4:1 to 1:4, most preferably 3:1 to 1:3 and especially 2:1 to 1:2.

[0184] Preferably, the relative weight ratio of water-soluble polymer to functionalized polyolefin is in the ratio of 11:1 to 1:2, preferably 10:1 to 1:1, more preferably 9:1 to 2:1, even more preferably 8:1 to 3:1, most preferably 7:1 to 4:1 and especially 6:1 to 5:1.

[0185] In these preferred embodiments, layer (f) contains, based on the total weight of layer (f), at most 10 wt.% polyolefin, more preferably 5 wt.%, even more preferably at most 2.5 wt.%, most preferably at most 1.0 wt.%, and in particular practically no (unfunctionalized) polyolefin.

[0186] In these preferred embodiments, the plastic film according to the invention preferably does not contain layer (e).

[0187] Preferably, layer (f) has a layer thickness in the range from 0.5 to 25 pm, preferably 0.5 to 10 pm.

[0188] In preferred embodiments of the plastic film according to the invention, layer (f) has a layer thickness of at least 1.0 pm, more preferably at least 2.0 pm, even more preferably at least 3.0 pm, most preferably at least 4.0 pm and in particular at least 5.0 pm.

[0189] In preferred embodiments of the plastic film according to the invention, layer (f) has a layer thickness of at most 9.0 pm, more preferably at most 8.0 pm, even more preferably at most 7.0 pm, most preferably at most 6.0 pm and in particular at most 5.0 pm.

[0190] In preferred embodiments of the plastic film according to the invention, layer (f) has the same layer structure as layer (b).

[0191] In other preferred embodiments of the plastic film according to the invention, layer (f) has a different layer structure than layer (b).

[0192] Preferably, the layer (g) contains or is based on one or more polyolefins independently selected from the group consisting of - thermoplastic olefin homopolymers; and / or - thermoplastic olefin copolymers of α,β-unsaturated olefins having 2 to 10 carbon atoms.

[0193] Layer (g) preferably contains or is based on one or more polyolefins selected independently from the group consisting of polyethylene, polypropylene, polybutylene, polyisobutylene (PI), copolymers and / or mixtures of at least two of the polymers mentioned; preferably polypropylene.

[0194] In preferred embodiments, the layer (g) contains, based on the total weight of the layer (g), at least 50 wt.% polyolefin, more preferably at least 60 wt.%, even more preferably at least 70% by weight, most preferably at least 80% by weight and especially at least 90% by weight.

[0195] In preferred embodiments, layer (g) contains, based on the total weight of layer (g), at most 10 wt.% water-soluble polymer, more preferably 5 wt.%, even more preferably at most 2.5 wt.%, most preferably at most 1.0 wt.%, and in particular practically no water-soluble polymer at all.

[0196] In other preferred embodiments, layer (g) contains a mixture of polyolefin and water-soluble polymer.

[0197] Preferably, the water-soluble polymer is independently selected from the group consisting of butenediol-vinyl alcohol copolymer (BVOH), polyvinyl alcohol (PVOH), polyvinyl acetate (PVA), polyvinylpyrrolidone (PVP), polyethylene oxide (PEO), polyacrylamide (PAM), and polylactic acid (PLA); preferably butenediol-vinyl alcohol copolymer (BVOH).

[0198] Preferably, the content of water-soluble polymer is greater than the content of polyolefin.

[0199] Preferably, the relative weight ratio of water-soluble polymer to polyolefin is in the ratio of 10:1 to 1:10, preferably 8:1 to 1:8, more preferably 6:1 to 1:6, even more preferably 4:1 to 1:4, most preferably 3:1 to 1:3 and especially 2:1 to 1:2.

[0200] Preferably, the relative weight ratio of water-soluble polymer to polyolefin is in the ratio of 11:1 to 1:2, preferably 10:1 to 1:1, more preferably 9:1 to 2:1, even more preferably 8:1 to 3:1, most preferably 7:1 to 4:1 and especially 6:1 to 5:1.

[0201] Preferably, based on the weight of the layer (g) independently - the polyolefin content is in the range of 15±14 wt.%, preferably 15±12 wt.%, more preferably 15±10 wt.%, even more preferably 15±8.0 wt.%, most preferably 15±6.0 wt.%, and in particular 15±4.0 wt.%, and - the content of water-soluble polymer in the range of 85±14 wt%, preferably 85±12 wt%, more preferably 85±10 wt%, even more preferably 85±8.0 wt%, most preferably 85±6.0 wt%, and in particular 85±4.0 wt%.

[0202] Preferably, layer (g) has a layer thickness in the range of 0.5 to 100 pm, preferably 0.5 to 25 pm.

[0203] In preferred embodiments of the plastic film according to the invention, layer (g) has a layer thickness of at least 4.0 pm, more preferably at least 8.0 pm, even more preferably at least 12 pm, most preferably at least 16 pm and in particular at least 20 pm.

[0204] In preferred embodiments of the plastic film according to the invention, layer (g) has a layer thickness of at most 22 pm, more preferably at most 19 pm, even more preferably at most 16 pm, most preferably at most 13 pm and in particular at most 10 pm.

[0205] In preferred embodiments of the plastic film according to the invention, layer (g) has the same layer structure as layer (a).

[0206] In other preferred embodiments of the plastic film according to the invention, layer (g) has a different layer structure than layer (a).

[0207] Preferably, layer (a) and layer (g) can be separated from one another after the cleavage of the plastic film according to the invention along the at least one layer which contains or is based on water-soluble polymer.

[0208] Preferably, layer (g) differs from layer (a) in at least one property.

[0209] Preferably, the at least one property is selected from color; density; amount and / or type of additives, in particular fillers; amount and / or type of surface coating; amount and / or type of impurities, preferably adhesive components.

[0210] Preferably, layer (a) and layer (g) can be separated from one another based on the at least one property.

[0211] In preferred embodiments, layer (a) has a different color than layer (g). Layers (a) and (g) can preferably be separated from one another based on their different colors. The separation of layers (a) and (g) preferably occurs after the plastic film according to the invention has been cleaved along the at least one layer that contains or is based on a water-soluble polymer.

[0212] In preferred embodiments, layer (a) is black and layer (g) is white.

[0213] In other preferred embodiments, layer (a) is white and layer (g) is black.

[0214] In preferred embodiments, layer (a) has a different density than layer (g); preferably due to the different amount and / or type of fillers. Layers (a) and (g) can preferably be separated from one another based on their different densities. The separation of layers (a) and (g) preferably occurs after the cleavage of the plastic film according to the invention along the at least one layer that contains or is based on a water-soluble polymer.

[0215] In preferred embodiments, layer (a) contains a larger total amount of filler, preferably layered silicate, than layer (g).

[0216] In other preferred embodiments, layer (a) contains a smaller total amount of filler, preferably layered silicate, than layer (g).

[0217] In preferred embodiments, layer (a) has a greater density than layer (g).

[0218] In other preferred embodiments, layer (a) has a lower density than layer (g).

[0219] The plastic film according to the invention can be used in building and construction applications, e.g., as a release film with release properties for bitumen roofing membranes. In this application, the plastic film according to the invention can be used to cover bituminous adhesives. The plastic film according to the invention preferably contains a white polyolefin layer, a black polyolefin layer, optionally coated with a non-adhesive surface coating, and a polyamide and / or polyester layer. The polyamide and / or polyester layer can prevent the adhesive components from bleeding through the plastic film according to the invention. Nevertheless, one-sided migration of adhesive components into the outer layer facing the adhesive can occur, preferably the black polyolefin layer of the plastic film according to the invention.For this reason, it may be advantageous for later reuse to separate the white, uncontaminated and preferably uncoated polyolefin layer from the black polyolefin layer contaminated with bituminous substances and possibly coated with a non-adhesive surface coating during the recycling process. A density gradient, for example, through the use of fillers (e.g., chalk) or pigments (e.g., titanium dioxide), is suitable for this purpose.

[0220] In preferred embodiments, the plastic film according to the invention is surface-coated on at least one side; preferably, the plastic film comprises a first outer layer and a second outer layer; a first surface coating which covers at least part of the first outer layer of the plastic film; and optionally a second surface coating which optionally covers at least part of the second outer layer of the plastic film.

[0221] Preferably, layer (a) forms the first outer layer.

[0222] In preferred embodiments of the plastic film according to the invention, the first surface coating is adhesive.

[0223] For the purpose of description, "dehesive" means a release force according to FINAT test method FTM10 (Tesa® test tape 7475, peel speed 300 mm / min, storage conditions 20h / 70°C) of not more than 50 cN / cm, more preferably not more than 40 cN / cm, even more preferably not more than 30 cN / cm.

[0224] Preferably, the first surface coating is based on polysiloxane.

[0225] In preferred embodiments of the plastic film according to the invention, the first surface coating is based on at least one cured polysiloxane which is selected from the group consisting of addition-crosslinked, preferably metal-catalyzed addition-crosslinked, condensation-crosslinked, radically crosslinked, and / or cationically crosslinked polysiloxanes.

[0226] In preferred embodiments of the plastic film according to the invention, the first surface coating is based on at least one cured polysiloxane which is selected from the group consisting of polydialkylsiloxanes, preferably polydimethylsiloxanes, and polyalkylarylsiloxanes, preferably polymethylphenylsiloxanes.

[0227] In other preferred embodiments of the plastic film according to the invention, the first surface coating is adhesive.

[0228] Preferably, the first surface coating is based on a pressure-sensitive adhesive.

[0229] In preferred embodiments of the plastic film according to the invention, the pressure-sensitive adhesive is selected from the group consisting of acrylate-based pressure-sensitive adhesives, rubber-based pressure-sensitive adhesives, polyisobutylene-based pressure-sensitive adhesives, and hot melts.

[0230] In further preferred embodiments of the plastic film according to the invention, the first surface coating is based on printing ink or varnish.

[0231] In preferred embodiments, the first surface coating contains a mixture of polysiloxane and water-soluble polymer.

[0232] Preferably, the water-soluble polymer is selected from the group consisting of butenediol-vinyl alcohol copolymer (BVOH), polyvinyl alcohol (PVOH), polyvinyl acetate (PVA), polyvinylpyrrolidone (PVP), polyethylene oxide (PEO), polyacrylamide (PAM), and polylactic acid (PLA).

[0233] Preferably, the relative weight ratio of water-soluble polymer to polysiloxane is in the ratio of 10:1 to 1:10, preferably 8:1 to 1:8, more preferably 6:1 to 1:6, even more preferably 4:1 to 1:4, most preferably 3:1 to 1:3 and in particular 2:1 to 1:2.

[0234] In preferred embodiments of the plastic film according to the invention, in particular when the first surface coating is adhesive, the first surface coating has a basis weight of at most 5.0 g / m 2 , preferably not more than 4.0 g / m 2 , more preferably not more than 3.0 g / m 2 , most preferably not more than 2.0 g / m 2 and in particular not more than 1.0 g / m2 The basis weight is preferably determined according to FINAT test method FTM7.

[0235] In other preferred embodiments of the plastic film according to the invention, in particular when the first surface coating is adhesive, the first surface coating has a basis weight of at most 100 g / m 2 , preferably not more than 80 g / m 2 , even more preferably at most 60 g / m 2 , preferably not more than 40 g / m 2 and in particular not more than 20 g / m 2 The basis weight is also preferably determined according to FINAT.

[0236] The first surface coating can cover the first outer side of the plastic film according to the invention partially or completely, preferably completely. To ensure sufficient resistance to moisture or wetness for the application, the surface coating should be applied as completely as possible. In the case of partially coated surfaces, the use of a varnish is therefore recommended, which can, for example, be printed over the entire surface to cover the areas covered by the first surface coating as well as the areas not covered by the first surface coating.

[0237] In preferred embodiments of the plastic film according to the invention, the second surface coating is adhesive.

[0238] Preferably, the second surface coating is based on polysiloxane.

[0239] In preferred embodiments of the plastic film according to the invention, the second surface coating is based on at least one cured polysiloxane which is selected from the group consisting of addition-crosslinked, preferably metal-catalyzed addition-crosslinked, condensation-crosslinked, radically crosslinked, and / or cationically crosslinked polysiloxanes.

[0240] In preferred embodiments of the plastic film according to the invention, the second surface coating is based on at least one cured polysiloxane which is selected from the group consisting of polydialkylsiloxanes, preferably polydimethylsiloxanes, and polyalkylarylsiloxanes, preferably polymethylphenylsiloxanes.

[0241] In other preferred embodiments of the plastic film according to the invention, the second surface coating is adhesive.

[0242] Preferably, the second surface coating is based on a pressure-sensitive adhesive.

[0243] Preferably, the pressure-sensitive adhesive is selected from the group consisting of acrylate-based pressure-sensitive adhesives, rubber-based pressure-sensitive adhesives, polyisobutylene-based pressure-sensitive adhesives, and hot melts.

[0244] In further preferred embodiments of the plastic film according to the invention, the second surface coating is based on printing ink or varnish.

[0245] In preferred embodiments of the plastic film according to the invention, in particular when the second surface coating is adhesive, the second surface coating has a basis weight of at most 5.0 g / m 2 , preferably not more than 4.0 g / m 2 , more preferably not more than 3.0 g / m 2 , most preferably not more than 2.0 g / m 2 and in particular not more than 1.0 g / m 2The basis weight is preferably determined according to FINAT test method FTM7.

[0246] In other preferred embodiments of the plastic film according to the invention, in particular when the second surface coating is adhesive, the second surface coating has a basis weight of at most 100 g / m 2 , preferably not more than 80 g / m 2 , more preferably not more than 60 g / m 2 , preferably not more than 40 g / m 2 and in particular not more than 20 g / m 2 The basis weight is also preferably determined according to FINAT.

[0247] The second surface coating can cover part or all of the second outer side of the plastic film according to the invention, preferably the entire surface. To ensure sufficient resistance to moisture or wetness for the application, the surface coating should be applied as completely as possible. In the case of partially coated surfaces, the use of a varnish is therefore recommended, which can, for example, be printed over the entire surface to cover the areas covered by the second surface coating as well as the areas not covered by the second surface coating.

[0248] In preferred embodiments of the plastic film according to the invention, the plastic film according to the invention is surface-coated on one side, wherein the first surface coating is adhesive.

[0249] In other preferred embodiments of the plastic film according to the invention, the plastic film according to the invention is surface-coated on one side, wherein the first surface coating is adhesive.

[0250] In preferred embodiments of the plastic film according to the invention, the plastic film according to the invention is surface-coated on two sides, wherein the first surface coating is dehesive and the second surface coating is adhesive.

[0251] In preferred embodiments of the plastic film according to the invention, the plastic film according to the invention is surface-coated on two sides, wherein the first surface coating is adhesive and the second surface coating is dehesive.

[0252] In preferred embodiments, the plastic film according to the invention comprises between (i) a layer, preferably any layer, containing or based on polyolefin; and (ii) a layer, preferably any layer, containing or based on polyamide and / or polyester; at least one layer containing or based on water-soluble polymer.

[0253] Preferably, the layers of the plastic film according to the invention are arranged in such a way that between one or more layers which contain or are based on polyolefin and one or more several layers which contain or are based on polyamide and / or polyester, at least one layer is arranged in each case which contains or is based on water-soluble polymer. Preferably, no layer which contains or is based on polyolefin is arranged adjacent to a layer which contains or is based on polyamide and / or polyester, or is in direct contact therewith. This preferably enables separation of the material of the one or more layers which contain or are based on polyolefin from the material of the one or more layers which contain or are based on polyamide and / or polyester, and the subsequent recycling of the material, which may be in a pure form.

[0254] The plastic film according to the invention preferably comprises layer (a) and optionally layer (g), which contains or is based on polyolefin; and layer (d), which contains or is based on polyamide and / or polyester. The plastic film according to the invention preferably additionally comprises layer (b) and / or layer (f), which contains polyolefin.

[0255] The plastic film according to the invention preferably comprises (i) the layer (a), the layer (b) and the layer (d) or consists thereof; wherein the layer (b) is preferably arranged between the layer (a) and the layer (d); preferably is in direct contact with the layer (a) and / or with the layer (d); wherein the layer (b) preferably contains, in addition to the functionalized polyolefin, further polymers, preferably water-soluble polymer, preferably the same water-soluble polymer which is contained in the layer (c); or (ii) layer (a), layer (b), layer (c) and layer (d) or consists thereof; wherein layer (b) is preferably arranged between layer (a) and layer (c); preferably is in direct contact with layer (a) and / or with layer (c); wherein layer (b), based on the total weight of layer (b), preferably contains at most 10% by weight of water-soluble polymer, more preferably 5% by weight, even more preferably at most 2.5% by weight, most preferably at most 1.0% by weight, and in particular practically no water-soluble polymer at all.

[0256] In preferred embodiments, the plastic film according to the invention comprises - the layer (a); - layer (b); and - the layer (d); or consists of it.

[0257] Preferably, layer (b) is arranged between layer (a) and layer (d); preferably, it is in direct contact with layer (a) and / or layer (d).

[0258] The plastic film according to the invention preferably comprises - the layer (a); - the layer (b); - the layer (d); and - the layer (f); or consists of it.

[0259] Preferably, layer (d) is arranged between layer (b) and layer (f); preferably, it is in direct contact with layer (b) and / or layer (f).

[0260] The plastic film according to the invention preferably comprises - the layer (a); - the layer (b); - the layer (d); - the layer (f); and - the layer (g) or consists of it.

[0261] Preferably, layer (f) is arranged between layer (d) and layer (g); preferably, it is in direct contact with layer (d) and / or with layer (g).

[0262] In other preferred embodiments, the plastic film according to the invention comprises - the layer (a); - the layer (b); - layer (c); and - the layer (d); or consists of it.

[0263] Preferably, layer (b) is arranged between layer (a) and layer (c); preferably, it is in direct contact with layer (a) and / or layer (c).

[0264] Preferably, layer (c) is arranged between layer (b) and layer (d); preferably, it is in direct contact with layer (b) and / or with layer (d).

[0265] The plastic film according to the invention preferably comprises - the layer (a); - the layer (b); - the layer (c); - the layer (d); and - the layer(s); or consists of it.

[0266] Preferably, layer (d) is arranged between layer (c) and layer (e); preferably, it is in direct contact with layer (c) and / or with layer (e).

[0267] The plastic film according to the invention preferably comprises - the layer (a); - the layer (b); - the layer (c); - the layer (d); - the layer(s); and - the layer (f); or consists of it.

[0268] Preferably, layer (e) is arranged between layer (d) and layer (f); preferably, it is in direct contact with layer (d) and / or with layer (f).

[0269] The plastic film according to the invention preferably comprises - the layer (a); - the layer (b); - the layer (c); - the layer (d); - the layer(s); - the layer (f); and - the layer (g); or consists of it.

[0270] Preferably, layer (f) is arranged between layer (e) and layer (g); preferably, it is in direct contact with layer (e) and / or layer (g).

[0271] In preferred embodiments, the plastic film according to the invention has the following structure: - layer (a) which is based on polyolefin, preferably polypropylene; - layer (b) containing the same polyolefin as contained in layer (a) and functionalized polyolefin; - layer (c) based on water-soluble polymer, preferably butenediol-vinyl alcohol copolymers (BVOH) and / or polyvinyl alcohols (PVOH); - layer (d) based on polyamide; - layer(s) based on water-soluble polymer, preferably butenediol-vinyl alcohol copolymers (BVOH) and / or polyvinyl alcohols (PVOH); - layer (f) containing the same polyolefin as contained in layer (g) and functionalized polyolefin; - Layer (g) based on polyolefin, preferably polypropylene.

[0272] In preferred embodiments, the plastic film according to the invention has the following structure: - layer (c) based on water-soluble polymer, preferably butenediol-vinyl alcohol copolymers (BVOH) and / or polyvinyl alcohols (PVOH); - layer (d) based on polyamide; - layer(s) based on water-soluble polymer, preferably butenediol-vinyl alcohol copolymers (BVOH) and / or polyvinyl alcohols (PVOH); - layer (f) containing the same polyolefin as contained in layer (g) and functionalized polyolefin; - Layer (g) based on polyolefin.

[0273] In preferred embodiments, the plastic film according to the invention has the following structure: - layer (a) which is based on polyolefin, preferably polypropylene; - layer (b) containing water-soluble polymer, preferably butenediol-vinyl alcohol copolymers (BVOH) and / or polyvinyl alcohols (PVOH), which is present in a mixture with functionalized polyolefin; - layer (d) based on polyamide; - layer (f) containing water-soluble polymer, preferably butenediol-vinyl alcohol copolymers (BVOH) and / or polyvinyl alcohols (PVOH), which is present in a mixture with functionalized polyolefin; - Layer (g) based on polyolefin, preferably polypropylene.

[0274] In preferred embodiments, the plastic film has a layer structure selected from (i) (a)-(d); (n) (a)-(b)-(c); (a)-(b)-(d); (a)-(b)-(e); (a)-(b)-(f); (a)-(b)-(g); (a)-(c)-(d); (a)-(c)-(e); (a)-(c)-(f); (a)-(c)-(g); (a)-(d)-(g); (a)-(d)-(e); (a)-(d)-(f); (in) (a)-(b)-(c)-(d); (a)-(b)-(c)-(e); (a)-(b)-(c)-(f); (a)-(b)-(c)-(g); (a)-(b)-(d)-(e); (a)-(b)-(d)-(f); (a)-(b)-(d)-(g); (iv) (a)-(b)-(c)-(d)-(e); (a)-(b)-(c)-(d)-(f); (a)-(b)-(c)-(d)-(g); (a)-(b)-(c)-(f)-(g); (a)-(b)-(d)-(f)-(g); (a)-(c)-(d)-(e)-(g); (v) (a)-(b)-(c)-(d)-(e)-(g); (a)-(b)-(c)-(d)-(f)-(g); (a)-(b)-(c)-(e)-(f)-(g); and (vi) (a)-(b)-(c)-(d)-(e)-(f)-(g).

[0275] Preferably, the plastic film is cleavable along the at least one layer which contains or is based on water-soluble polymer when treated in a water bath, optionally at elevated temperature and after a sufficient exposure time.

[0276] In preferred embodiments, the plastic film according to the invention can be split at elevated temperature in a water bath and contamination of the plastic film is previously washed off at a lower temperature.

[0277] Preferably, the plastic film according to the invention is split into at least two film layers; preferably at least one layer containing or based on polyolefin and at least one layer containing or based on polyamide and / or polyester.

[0278] In preferred embodiments, the plastic film according to the invention comprises layers (a), (d) and (g), which are obtained as separate layers upon cleavage of the plastic film according to the invention.

[0279] All layers of the plastic film according to the invention can contain conventional additives in conventional amounts. Conventional additives are selected from the group consisting of fillers, such as CaCCE, phyllosilicates such as talc, plasticizers; lubricants; emulsifiers; pigments; rheology additives; catalysts; flow control agents; impact modifiers, optical brighteners; light stabilizers; antioxidants; and clarifying agents, such as substituted or unsubstituted Bisbenzylidene sorbitols; flame retardants; antistatic agents; UV absorbers such as benzoxazinones; blowing agents; and thiosynergists such as thiodipropionic acid dilauryl esters or thiodipropionic acid distearyl esters. A preferred plasticizer for water-soluble polymers is glycerol.

[0280] The plastic film according to the invention can be produced by conventional methods known to those skilled in the art and, if appropriate, subsequently provided with the first surface coating on the first outer side. Preferred methods are blown film extrusion or casting processes.

[0281] The layers can be applied to the substrate by coextrusion (film extrusion), as a polymer coating (extrusion coating), or as a standalone coating (coating, printing, varnish) prior to the first and second surface coatings (silicone, adhesive, etc.). The water-soluble polymer preferably forms sufficient inherent adhesion to the polyamide and / or polyester layer through coextrusion. Bonding to the polypropylene layer, on the other hand, is preferably achieved using functionalized polyolefins, e.g., with MAH. The water-soluble polymer is also preferably suitable for the blown film process and can be extruded on conventional or existing extrusion lines (e.g., E37). Additional adaptations familiar to those skilled in the art, such as corona treatment, may be necessary to achieve sufficient bonding.

[0282] The plastic film according to the invention can be subjected to conventional recycling processes, which typically involve treatment in a water bath. Due to the inventive structure of the plastic film, it is now possible to dissolve the water-soluble layer or the water-soluble polymers (almost) completely during the recycling process. This separates the plastic film according to the invention into at least two layers, which (mainly) contain only polyolefin or polyamide and / or polyester. Due to the density differences between polyolefin film layers (density < 1.0 g / cm 3 ) and polyamide and / or polyester film layers (density > 1.0 g / cm 3), the individual material streams can be easily separated from each other in a water bath. The resulting aqueous waste, which contains the water-soluble polymer, is easy to dispose of when biodegradable and environmentally safe polymers are used and does not negatively impact the sustainability of the new film design.

[0283] A further aspect of the invention relates to a process for producing a plastic film according to the invention as described above by blown film coextrusion.

[0284] In the process according to the invention, the extrusion of the plastic film preferably takes place in one step.

[0285] A further aspect of the invention relates to a plastic film obtainable by the inventive method described above.

[0286] A further aspect of the invention relates to the use of the above-described inventive plastic film for recycling some of its components. Preferably, the plastic film is split along at least one layer containing or based on a water-soluble polymer after or during treatment in a water bath, optionally at elevated temperature and after a sufficient exposure time.

[0287] The functioning of the invention is explained schematically using Figures 1 and 2.

[0288] Figure 1 shows schematically a cross section of a plastic film according to the invention with a layer (1) based on a polyolefin, e.g. PP, a layer (2) containing functionalized polyolefin, e.g. PP+MAH, a layer (3) based on a water-soluble polymer, e.g. BVOH / PVOH, a layer (4) based on a water-soluble polymer, e.g. BVOH / PVOH, a layer (5) containing functionalized polyolefin, e.g. PP+MAH, and a layer (7) based on a polyolefin, e.g. PP.

[0289] Figure 2 shows the treatment of the plastic film shown in Figure 1 in a container (8) precipitated with warm water (9). The water-soluble polymer dissolves in the water (9), so that the water-soluble polymer-based layers (3) and (5) are dissolved. As a result, the composite of the polyolefin-based layer (1) and the functionalized polyolefin-containing layer (2) separates from the polyamide-based layer (4) and the composite of the functionalized polyolefin-containing layer (6) and the polyolefin-based layer (7). The separated layers or composites can be disposed of separately or recycled.

[0290] The following examples serve to illustrate the invention but are not to be construed as limiting. Example 1:

[0291] Multilayer plastic films were produced by blown film co-extrusion. The individual layers are adjacent to each other in the order listed in the table below: Example 2:

[0292] Multilayer plastic films were produced by blown film co-extrusion. The individual layers are adjacent to each other in the order listed in the table below: Example 3:

[0293] A multilayer plastic film was produced by blown film co-extrusion. The individual layers are adjacent to each other in the order listed in the table below: Example 4:

[0294] A multilayer plastic film was produced by blown film co-extrusion. The individual layers are adjacent to each other in the order listed in the table below:

Claims

Patent claims:

1. A plastic film which (a) a layer (a) containing or based on polyolefin; (b) optionally a layer (b) containing or based on functionalized polyolefin; (c) optionally a layer (c) based on water-soluble polymer, preferably butenediol-vinyl alcohol copolymers (BVOH) and / or polyvinyl alcohols (PVOH); (d) a layer (d) containing or based on polyamide and / or polyester; (e) optionally a layer (e) based on water-soluble polymer, preferably butenediol-vinyl alcohol copolymers (BVOH) and / or polyvinyl alcohols (PVOH); (f) optionally a layer (f) containing or based on functionalized polyolefin; and (g) optionally a layer (g) which contains or is based on polyolefin; comprises or consists of; wherein the plastic film comprises at least one layer which contains or is based on water-soluble polymer, preferably butenediol-vinyl alcohol copolymer (BVOH).

2. The plastic film according to claim 1, wherein the plastic film has a total layer thickness in the range of 10 to 250 pm, preferably 30 to 250.

3. The plastic film according to claim 1 or 2, wherein the plastic film has a total layer thickness of at least 20 pm, more preferably at least 25 pm, even more preferably at least 30 pm, most preferably at least 35 pm and in particular at least 40 pm.

4. The plastic film according to one of the preceding claims, wherein the plastic film has a total layer thickness of at most 90 pm, more preferably at most 80 pm, even more preferably at most 70 pm, most preferably at most 60 pm and in particular at most 50 pm.

5. The plastic film according to one of the preceding claims, wherein the plastic film has a symmetrical layer structure.

6. The plastic film according to one of the preceding claims, which is extrudable, preferably coextrudable in one step, preferably by blown film coextrusion.

7. The plastic film according to any one of the preceding claims, wherein the at least one layer contains or is based on extrudable, water-soluble polymer.

8. The plastic film according to any one of the preceding claims, wherein the at least one layer contains or is based on one or more water-soluble polymers independently selected from (i) fully synthetic water-soluble polymers; (ii) semi-synthetic or natural water-soluble polymers.

9. The plastic film according to any one of the preceding claims, wherein the at least one layer contains or is based on one or more water-soluble polymers selected from polymers or copolymers of vinyl acetate, vinylpyrrolidone, ethylene oxide, acrylamide, and lactic acid; preferably polymers or copolymers of vinyl acetate.

10. The plastic film according to any one of the preceding claims, wherein the at least one layer contains or is based on one or more water-soluble polymers independently selected from the group consisting of butenediol-vinyl alcohol copolymer (BVOH), polyvinyl alcohol (PVOH), polyvinyl acetate (PVA), polyvinylpyrrolidone (PVP), polyethylene oxide (PEO), polyacrylamide (PAM), and polylactic acid (PLA).

11. The plastic film according to any one of the preceding claims, wherein the at least one layer contains or is based on butenediol-vinyl alcohol copolymer (BVOH).

12. The plastic film according to any one of the preceding claims, wherein the at least one layer contains or is based on one or more water-soluble polymers having an ethylene group content of at most 10 mol%, more preferably at most 5.0 mol%, even more preferably at most 2.5 mol%, and in particular practically no ethylene groups at all.

13. The plastic film according to any one of the preceding claims, wherein the total content of water-soluble polymer contained in the plastic film, based on the total weight of the plastic film, is at least 0.5 wt.%, more preferably at least 1.0 wt.%, even more preferably at least 2.0 wt.%, most preferably at least 3.0 wt.% and in particular at least 4.0 wt.%.

14. The plastic film according to any one of the preceding claims, wherein the total content of water-soluble polymer contained in the plastic film, based on the total weight of the plastic film, is at most 18 wt.%, more preferably at most 16 wt.%, nor more preferably at most 14 wt.%, most preferably at most 12 wt.% and in particular at most 10 wt.%.

15. The plastic film according to any one of the preceding claims, wherein the total content of water-soluble polymer contained in the plastic film, based on the total weight of the plastic film, is at most 10 wt.%, more preferably at most 9.0 wt.%, even more preferably at most 8.0 wt.%, most preferably at most 7.0 wt.% and in particular at most 6.0 wt.%.

16. The plastic film according to any one of the preceding claims, wherein the layer (a) contains or is based on one or more polyolefins independently selected from the group consisting of - thermoplastic olefin homopolymers; and / or - thermoplastic olefin copolymers of α,β-unsaturated olefins having 2 to 10 carbon atoms.

17. The plastic film according to any one of the preceding claims, wherein layer (a) contains or is based on one or more polyolefins independently selected from the group consisting of polyethylene, polypropylene, polybutylene, polyisobutylene (PI), copolymers and / or mixtures of at least two of the aforementioned polymers; preferably polypropylene.

18. The plastic film according to any one of the preceding claims, wherein layer (a), based on the total weight of layer (a), contains at least 50 wt.% polyolefin, more preferably at least 60 wt.%, even more preferably at least 70 wt.%, most preferably at least 80 wt.% and in particular at least 90 wt.%.

19. The plastic film according to any one of the preceding claims, wherein layer (a), based on the total weight of layer (a), contains at most 10 wt.% water-soluble polymer, more preferably 5 wt.%, even more preferably at most 2.5 wt.%, most preferably at most 1.0 wt.%, and in particular practically no water-soluble polymer at all.

20. The plastic film according to any one of the preceding claims, wherein layer (a) contains a mixture of polyolefin and water-soluble polymer.

21. The plastic film according to claim 20, wherein the water-soluble polymer is independently selected from the group consisting of butenediol-vinyl alcohol copolymer (BVOH), polyvinyl alcohol (PVOH), polyvinyl acetate (PVA), polyvinylpyrrolidone (PVP), polyethylene oxide (PEO), polyacrylamide (PAM), and polylactic acid (PLA); preferably butenediol-vinyl alcohol copolymer (BVOH).

22. The plastic film according to claim 20 or 21, wherein the relative weight ratio of water-soluble polymer to polyolefin is in the ratio of 10:1 to 1:10, preferably 8:1 to 1:8, more preferably 6:1 to 1:6, even more preferably 4:1 to 1:4, most preferably 3:1 to 1:3 and in particular 2:1 to 1:

2.

23. The plastic film according to one of the preceding claims, wherein the layer (a) has a layer thickness in the range of 0.5 to 100 pm, preferably 0.5 to 25 pm.

24. The plastic film according to any one of the preceding claims, wherein layer (a) has a layer thickness of at least 4.0 pm, more preferably at least 8.0 pm, even more preferably at least 12 pm, most preferably at least 16 pm and in particular at least 20 pm.

25. The plastic film according to any one of the preceding claims, wherein layer (a) has a layer thickness of at most 22 pm, more preferably at most 19 pm, even more preferably at most 16 pm, most preferably at most 13 pm and in particular at most 10 pm.

26. The plastic film according to any one of the preceding claims, wherein layer (b) contains or is based on anhydride-modified polyolefin or acid-modified polyolefin.

27. The plastic film according to any one of the preceding claims, wherein layer (b) contains, in addition to the functionalized polyolefin, further polymers, preferably the same polyolefin contained in layer (a) and / or the same water-soluble polymer contained in layer (c).

28. The plastic film according to any one of the preceding claims, wherein layer (b), based on the total weight of layer (b), contains at least 10 wt.% functionalized polyolefin, more preferably at least 15 wt.%, even more preferably at least 20 wt.%, most preferably at least 25 wt.% and in particular at least 30 wt.%.

29. The plastic film according to one of the preceding claims, wherein layer (b) contains, in addition to the functionalized polyolefin, further polymers, preferably the same polyolefin which is contained in layer (a).

30. The plastic film according to any one of the preceding claims, wherein layer (b), based on the total weight of layer (b), contains at least 30 wt.% polyolefin and / or functionalized polyolefin, more preferably at least 40 wt.%, even more preferably at least 50 wt.%, most preferably at least 60 wt.% and in particular at least 70 wt.%.

31. The plastic film according to any one of the preceding claims, wherein the layer (b), based on the total weight of the layer (b), contains at most 10 wt.% water-soluble polymer, more preferably 5 wt.%, even more preferably at most 2.5 wt.%, most preferably at most 1.0 wt.%, and in particular practically no water-soluble polymer at all.

32. The plastic film according to one of claims 1 to 28, wherein layer (b) contains, in addition to the functionalized polyolefin, further polymers, preferably the same water-soluble polymer which is contained in layer (c).

33. The plastic film according to claim 32, wherein layer (b), based on the total weight of layer (b), contains at least 5.0 wt.% functionalized polyolefin, more preferably at least 7.5 wt.%, even more preferably at least 10 wt.%, most preferably at least 12.5 wt.% and in particular at least 15 wt.%.

34. The plastic film according to claim 32 or 33, wherein layer (b), based on the total weight of layer (b), contains at least 45 wt% water-soluble polymer, more preferably at least 55 wt%, even more preferably at least 65 wt%, most preferably at least 75 wt% and in particular at least 85 wt%.

35. The plastic film according to any one of claims 32 to 34, wherein the relative weight ratio of water-soluble polymer to functionalized polyolefin is in the ratio of 10:1 to 1:10, preferably 8:1 to 1:8, more preferably 6:1 to 1:6, even more preferably 4:1 to 1:4, most preferably 3:1 to 1:3 and in particular 2:1 to 1:

2.

36. The plastic film according to any one of claims 32 to 35, wherein the layer (b), based on the total weight of the layer (b), contains at most 10 wt.% polyolefin, more preferably 5 wt.%, even more preferably at most 2.5 wt.%, most preferably at most 1.0 wt.%, and in particular practically no polyolefin at all.

37. The plastic film according to one of the preceding claims, wherein the layer (b) has a layer thickness in the range of 0.5 to 25 pm, preferably 0.5 to 10 pm.

38. The plastic film according to any one of the preceding claims, wherein the layer (b) has a layer thickness of at least 1.0 pm, more preferably at least 2.0 pm, even more preferably at least 3.0 pm, most preferably at least 4.0 pm and in particular at least 5.0 pm.

39. The plastic film according to any one of the preceding claims, wherein the layer (b) has a layer thickness of at most 9.0 pm, more preferably at most 8.0 pm, even more preferably at most 7.0 pm, most preferably at most 6.0 pm and in particular at most 5.0 pm.

40. The plastic film according to any one of the preceding claims, wherein layer (c) is based on extrudable, water-soluble polymer.

41. The plastic film according to any one of the preceding claims, wherein the layer (c) is based on one or more water-soluble polymers independently selected from (i) fully synthetic water-soluble polymers; (ii) semi-synthetic or natural water-soluble polymers.

42. The plastic film according to any one of the preceding claims, wherein layer (c) is based on one or more water-soluble polymers selected from polymers or copolymers of vinyl acetate, vinylpyrrolidone, ethylene oxide, acrylamide, and lactic acid; preferably polymers or copolymers of vinyl acetate.

43. The plastic film according to any one of the preceding claims, wherein the layer (c) is based on one or more water-soluble polymers independently selected from the group consisting of butenediol-vinyl alcohol copolymer (BVOH), polyvinyl alcohol (PVOH), polyvinyl acetate (PVA), polyvinylpyrrolidone (PVP), polyethylene oxide (PEO), polyacrylamide (PAM), and polylactic acid (PLA).

44. The plastic film according to any one of the preceding claims, wherein layer (c) is based on butenediol-vinyl alcohol copolymer (BVOH).

45. The plastic film according to any one of the preceding claims, wherein layer (c) is based on one or more water-soluble polymers having an ethylene group content of at most 10 mol%, more preferably at most 5.0 mol%, even more preferably at most 2.5 mol%, and in particular practically no ethylene groups at all.

46. ​​The plastic film according to any one of the preceding claims, wherein the layer (c) contains, based on the total weight of the layer (c), at least 50 wt.% water-soluble polymer, more preferably at least 60 wt.%, more preferably at least 70 wt.%, most preferably at least 80% by weight and in particular at least 90% by weight.

47. The plastic film according to any one of the preceding claims, wherein the layer (c), based on the total weight of the layer (c), contains at most 10 wt.% of non-water-soluble polymer, preferably polyolefin and / or functionalized polyolefin, more preferably 5 wt.%, even more preferably at most 2.5 wt.%, most preferably at most 1.0 wt.%, and in particular practically no polyolefin and / or functionalized polyolefin, preferably no non-water-soluble polymer at all.

48. The plastic film according to one of the preceding claims, wherein the layer (c) has a layer thickness in the range of 0.5 to 100 pm, preferably 0.5 to 25 pm.

49. The plastic film according to any one of the preceding claims, wherein the layer (c) has a layer thickness of at least 0.5 pm, more preferably at least 0.75 pm, even more preferably at least 1.0 pm, most preferably at least 1.25 pm and in particular at least 1.5 pm.

50. The plastic film according to any one of the preceding claims, wherein the layer (c) has a layer thickness of at most 9.0 pm, more preferably at most 8.0 pm, even more preferably at most 7.0 pm, most preferably at most 6.0 pm and in particular at most 5.0 pm.

51. The plastic film according to any one of the preceding claims, wherein the layer (c) has a layer thickness of at most 4.0 pm, more preferably at most 3.0 pm, even more preferably at most 2.5 pm, most preferably at most 2.0 pm and in particular at most 1.75 pm.

52. The plastic film according to any one of the preceding claims, wherein the layer (d), based on the total weight of the layer (d), contains at least 50 wt.% polyamide and / or polyester, more preferably at least 60 wt.%, even more preferably at least 70 wt.%, most preferably at least 80 wt.% and in particular at least 90 wt.%.

53. The plastic film according to any one of the preceding claims, wherein the layer (d), based on the total weight of the layer (d), contains at most 10 wt.% water-soluble polymer, more preferably 5 wt.%, even more preferably at most 2.5 wt.%, most preferably at most 1.0 wt.%, and in particular practically no water-soluble polymer at all.

54. The plastic film according to any one of the preceding claims, wherein the layer (d) comprises a mixture of (i) polyamide and / or polyester and (ii) water-soluble polymer.

55. The plastic film according to claim 54, wherein the water-soluble polymer is independently selected from the group consisting of butenediol-vinyl alcohol copolymer (BVOH), polyvinyl alcohol (PVOH), polyvinyl acetate (PVA), polyvinylpyrrolidone (PVP), polyethylene oxide (PEO), polyacrylamide (PAM), and polylactic acid (PLA), preferably butenediol-vinyl alcohol copolymer (BVOH).

56. The plastic film according to claim 54 or 55, wherein the relative weight ratio of water-soluble polymer to the total amount of polyamide and / or polyester is in the ratio of 10:1 to 1:10, preferably 8:1 to 1:8, more preferably 6:1 to 1:6, even more preferably 4:1 to 1:4, most preferably 3:1 to 1:3 and in particular 2:1 to 1:

2.

57. The plastic film according to any one of the preceding claims, which contains or is based on polyamide.

58. The plastic film according to one of the preceding claims, wherein the layer (d) has a layer thickness in the range of 0.5 to 100 pm, preferably 0.5 to 25 pm.

59. The plastic film according to any one of the preceding claims, wherein the layer (d) has a layer thickness of at least 1.0 pm, more preferably at least 2.0 pm, even more preferably at least 3.0 pm, most preferably at least 4.0 pm and in particular at least 5.0 pm.

60. The plastic film according to any one of the preceding claims, wherein the layer (d) has a layer thickness of at most 22 pm, more preferably at most 19 pm, even more preferably at most 16 pm, most preferably at most 13 pm and in particular at most 10 pm.

61. The plastic film according to any one of the preceding claims, wherein layer (e) is based on extrudable, water-soluble polymer.

62. The plastic film according to any one of the preceding claims, wherein the layer (e) is based on one or more water-soluble polymers independently selected from (i) fully synthetic water-soluble polymers; (ii) semi-synthetic or natural water-soluble polymers.

63. The plastic film according to any one of the preceding claims, wherein layer (e) is based on one or more water-soluble polymers selected from polymers or copolymers of vinyl acetate, vinylpyrrolidone, ethylene oxide, acrylamide, and lactic acid; preferably polymers or copolymers of vinyl acetate.

64. The plastic film according to any one of the preceding claims, wherein the layer (e) is based on one or more water-soluble polymers independently selected from the group consisting of butenediol-vinyl alcohol copolymer (BVOH), polyvinyl alcohol (PVOH), polyvinyl acetate (PVA), polyvinylpyrrolidone (PVP), polyethylene oxide (PEO), polyacrylamide (PAM), and polylactic acid (PLA).

65. The plastic film according to any one of the preceding claims, wherein layer (e) is based on butenediol-vinyl alcohol copolymer (BVOH).

66. The plastic film according to any one of the preceding claims, wherein the layer (e) is based on one or more water-soluble polymers having an ethylene group content of at most 10 mol%, more preferably at most 5.0 mol%, even more preferably at most 2.5 mol%, and in particular practically no ethylene groups at all.

67. The plastic film according to any one of the preceding claims, wherein the layer (e), based on the total weight of the layer (e), contains at least 50 wt.% water-soluble polymer, more preferably at least 60 wt.%, even more preferably at least 70 wt.%, most preferably at least 80 wt.% and in particular at least 90 wt.%.

68. The plastic film according to any one of the preceding claims, wherein the layer (e), based on the total weight of the layer (e), contains at most 10 wt.% of non-water-soluble polymer, preferably polyolefin and / or functionalized polyolefin, more preferably 5 wt.%, even more preferably at most 2.5 wt.%, most preferably at most 1.0 wt.%, and in particular practically no polyolefin and / or functionalized polyolefin, preferably no non-water-soluble polymer at all.

69. The plastic film according to one of the preceding claims, wherein the layer (e) has a layer thickness in the range of 0.5 to 100 pm, preferably 0.5 to 25 pm.

70. The plastic film according to any one of the preceding claims, wherein the layer (e) has a layer thickness of at least 0.5 pm, more preferably at least 0.75 pm, even more preferably at least 1.0 pm, most preferably at least 1.25 pm and in particular at least 1.5 pm.

71. The plastic film according to any one of the preceding claims, wherein the layer (e) has a layer thickness of at most 9.0 pm, more preferably at most 8.0 pm, even more preferably at most 7.0 pm, most preferably at most 6.0 pm and in particular at most 5.0 pm.

72. The plastic film according to any one of the preceding claims, wherein the layer (e) has a layer thickness of at most 4.0 pm, more preferably at most 3.0 pm, even more preferably at most 2.5 pm, most preferably at most 2.0 pm and in particular at most 1.75 pm.

73. The plastic film according to one of the preceding claims, wherein layer (e) has the same layer structure as layer (c).

74. The plastic film according to any one of the preceding claims, wherein layer (e) has a different layer structure than layer (c).

75. The plastic film according to any one of the preceding claims, wherein layer (f) contains or is based on anhydride-modified polyolefin or acid-modified polyolefin.

76. The plastic film according to any one of the preceding claims, wherein layer (f) contains, in addition to the functionalized polyolefin, further polymers, preferably the same polyolefin as is contained in layer (g) and / or the same water-soluble polymer as is contained in layer (e).

77. The plastic film according to any one of the preceding claims, wherein the layer (f), based on the total weight of the layer (f), contains at least 10 wt.% functionalized polyolefin, more preferably at least 15 wt.%, even more preferably at least 20 wt.%, most preferably at least 25 wt.% and in particular at least 30 wt.%.

78. The plastic film according to any one of the preceding claims, wherein layer (f) contains, in addition to the functionalized polyolefin, further polymers, preferably the same polyolefin which is contained in layer (g).

79. The plastic film according to any one of the preceding claims, wherein the layer (f), based on the total weight of the layer (f), contains at least 30 wt.% polyolefin and / or functionalized polyolefin, more preferably at least 40 wt.%, even more preferably at least 50 wt.%, most preferably at least 60 wt.% and in particular at least 70 wt.%.

80. The plastic film according to any one of the preceding claims, wherein the layer (f), based on the total weight of the layer (f), contains at most 10 wt.% water-soluble polymer, more preferably 5 wt.%, even more preferably at most 2.5 wt.%, most preferably at most 1.0 wt.%, and in particular practically no water-soluble polymer at all.

81. The plastic film according to one of claims 1 to 79, wherein the layer (f) contains, in addition to the functionalized polyolefin, further polymers, preferably the same water-soluble polymer which is contained in the layer (e).

82. The plastic film according to claim 81, wherein the layer (f), based on the total weight of the layer (f), contains at least 5.0 wt.% functionalized polyolefin, more preferably at least 7.5 wt.%, even more preferably at least 10 wt.%, most preferably at least 12.5 wt.% and in particular at least 15 wt.%.

83. The plastic film according to claim 81 or 82, wherein the layer (f), based on the total weight of the layer (f), contains at least 45 wt.% water-soluble polymer, more preferably at least 55 wt.%, even more preferably at least 65 wt.%, most preferably at least 75 wt.% and in particular at least 85 wt.%.

84. The plastic film according to any one of claims 81 to 83, wherein the relative weight ratio of water-soluble polymer to functionalized polyolefin is in the ratio of 10:1 to 1:10, preferably 8:1 to 1:8, more preferably 6:1 to 1:6, even more preferably 4:1 to 1:4, most preferably 3:1 to 1:3 and in particular 2:1 to 1:

2.

85. The plastic film according to any one of claims 81 to 84, wherein the layer (f), based on the total weight of the layer (f), contains at most 10 wt.% polyolefin, more preferably 5 wt.%, even more preferably at most 2.5 wt.%, most preferably at most 1.0 wt.%, and in particular practically no polyolefin at all.

86. The plastic film according to one of the preceding claims, wherein the layer (f) has a layer thickness in the range of 0.5 to 25 pm, preferably 0.5 to 10 pm.

87. The plastic film according to any one of the preceding claims, wherein the layer (f) has a layer thickness of at least 1.0 pm, more preferably at least 2.0 pm, even more preferably at least 3.0 pm, most preferably at least 4.0 pm and in particular at least 5.0 pm.

88. The plastic film according to any one of the preceding claims, wherein the layer (f) has a layer thickness of at most 9.0 pm, more preferably at most 8.0 pm, even more preferably at most 7.0 pm, most preferably at most 6.0 pm and in particular at most 5.0 pm.

89. The plastic film according to any one of the preceding claims, wherein layer (f) has the same layer structure as layer (b).

90. The plastic film according to any one of the preceding claims, wherein layer (f) has a different layer structure than layer (b).

91. The plastic film according to any one of the preceding claims, wherein the layer (g) contains or is based on one or more polyolefins independently selected from the group consisting of - thermoplastic olefin homopolymers; and / or - thermoplastic olefin copolymers of α,β-unsaturated olefins having 2 to 10 carbon atoms.

92. The plastic film according to any one of the preceding claims, wherein the layer (g) contains or is based on one or more polyolefins independently selected from the group consisting of polyethylene, polypropylene, polybutylene, polyisobutylene (PI), copolymers and / or mixtures of at least two of said polymers.

93. The plastic film according to any one of the preceding claims, wherein the layer (g), based on the total weight of the layer (g), contains at least 50 wt.% polyolefin, more preferably at least 60 wt.%, even more preferably at least 70 wt.%, most preferably at least 80 wt.% and in particular at least 90 wt.%.

94. The plastic film according to any one of the preceding claims, wherein the layer (g), based on the total weight of the layer (g), contains at most 10 wt.% water-soluble polymer, more preferably 5 wt.%, even more preferably at most 2.5 wt.%, most preferably at most 1.0 wt.%, and in particular practically no water-soluble polymer at all.

95. The plastic film according to any one of the preceding claims, wherein layer (g) contains a mixture of polyolefin and water-soluble polymer.

96. The plastic film according to claim 95, wherein the water-soluble polymer is independently selected from the group consisting of butenediol-vinyl alcohol copolymer (BVOH), Polyvinyl alcohol (PVOH), polyvinyl acetate (PVA), polyvinylpyrrolidone (PVP), polyethylene oxide (PEO), polyacrylamide (PAM), and polylactic acid (PLA); preferably butenediol-vinyl alcohol copolymer (BVOH).

97. The plastic film according to claim 95 or 96, wherein the relative weight ratio of water-soluble polymer to polyolefin is in the ratio of 10:1 to 1:10, preferably 8:1 to 1:8, more preferably 6:1 to 1:6, even more preferably 4:1 to 1:4, most preferably 3:1 to 1:3 and in particular 2:1 to 1:

2.

98. The plastic film according to one of the preceding claims, wherein the layer (g) has a layer thickness in the range of 0.5 to 100 pm, preferably 0.5 to 25 pm.

99. The plastic film according to any one of the preceding claims, wherein the layer (g) has a layer thickness of at least 4.0 pm, more preferably at least 8.0 pm, even more preferably at least 12 pm, most preferably at least 16 pm and in particular at least 20 pm.

100. The plastic film according to any one of the preceding claims, wherein the layer (g) has a layer thickness of at most 22 pm, more preferably at most 19 pm, even more preferably at most 16 pm, most preferably at most 13 pm and in particular at most 10 pm.

101. The plastic film according to any one of the preceding claims, wherein layer (g) has the same layer structure as layer (a).

102. The plastic film according to any one of the preceding claims, wherein layer (g) has a different layer structure than layer (a).

103. The plastic film according to any one of the preceding claims, wherein the layer (a) and the layer (g) can be separated from each other after the cleavage of the plastic film according to the invention along the at least one layer which contains or is based on water-soluble polymer.

104. The plastic film according to any one of the preceding claims, wherein layer (g) differs from layer (a) in at least one property; preferably, the at least one property is selected from color; density; amount and / or type of additives, in particular fillers; amount and / or type of surface coating; amount and / or type of impurities, preferably adhesive components; preferably, layer (a) and layer (g) can be separated from one another based on the at least one property.

105. The plastic film according to any one of the preceding claims, wherein layer (a) has a different color than layer (g).

106. The plastic film according to any one of the preceding claims, wherein layer (a) has a different density than layer (g).

107. The plastic film according to one of the preceding claims, wherein the plastic film is surface-coated on at least one side; preferably, the plastic film comprises a first outer layer and a second outer layer; a first surface coating which covers at least part of the first outer layer of the plastic film; and optionally a second surface coating which optionally covers at least part of the second outer layer of the plastic film.

108. The plastic film of claim 107, wherein the first surface coating is adhesive.

109. The plastic film according to claim 107 or 108, wherein the first surface coating is based on polysiloxane.

110. The plastic film according to any one of claims 107 to 109, wherein the first surface coating is based on at least one cured polysiloxane selected from the group consisting of addition-crosslinked, preferably metal-catalyzed addition-crosslinked, condensation-crosslinked, radically crosslinked, and / or cationically crosslinked polysiloxanes.

111. The plastic film according to any one of claims 107 to 110, wherein the first surface coating is based on at least one cured polysiloxane selected from the group consisting of polydialkylsiloxanes, preferably polydimethylsiloxanes, and polyalkylarylsiloxanes, preferably polymethylphenylsiloxanes.

112. The plastic film of claim 107, wherein the first surface coating is adhesive.

113. The plastic film of claim 112, wherein the first surface coating is based on a pressure-sensitive adhesive.

114. The plastic film according to claim 113, wherein the pressure-sensitive adhesive is selected from the group consisting of acrylate-based pressure-sensitive adhesives, rubber-based pressure-sensitive adhesives, polyisobutylene-based pressure-sensitive adhesives, and hot melts.

115. The plastic film of claim 107, wherein the first surface coating is based on printing ink or varnish.

116. The plastic film according to any one of claims 107 to 115, wherein the first surface coating (i) is non-adhesive and has a surface weight of not more than 5.0 g / m 2 , preferably not more than 4.0 g / m 2 , more preferably not more than 3.0 g / m 2 , most preferably not more than 2.0 g / m 2 and in particular not more than 1.0 g / m 2 has, or (ii) is adhesive and has a surface weight of not more than 100 g / m 2 , preferably not more than 80 g / m 2 , more preferably not more than 60 g / m 2 , preferably not more than 40 g / m 2and in particular not more than 20 g / m 2 has.

117. The plastic film according to any one of claims 107 to 116, wherein the second surface coating is adhesive.

118. The plastic film according to any one of claims 107 to 117, wherein the second surface coating is based on polysiloxane.

119. The plastic film according to any one of claims 107 to 118, wherein the second surface coating is based on at least one cured polysiloxane which is selected from the group consisting of addition-crosslinked, preferably metal-catalyzed addition-crosslinked, condensation-crosslinked, radically crosslinked, and / or cationically crosslinked polysiloxanes.

120. The plastic film according to any one of claims 107 to 119, wherein the second surface coating is based on at least one cured polysiloxane selected from the group consisting of polydialkylsiloxanes, preferably polydimethylsiloxanes, and polyalkylarylsiloxanes, preferably polymethylphenylsiloxanes.

121. The plastic film according to any one of claims 107 to 116, wherein the second surface coating is adhesive.

122. The plastic film of claim 121, wherein the second surface coating is based on a pressure-sensitive adhesive.

123. The plastic film according to claim 122, wherein the pressure-sensitive adhesive is selected from the group consisting of acrylate-based pressure-sensitive adhesives, rubber-based pressure-sensitive adhesives, polyisobutylene-based pressure-sensitive adhesives, and hot melts.

124. The plastic film according to any one of claims 107 to 116, wherein the second surface coating is based on printing ink or varnish.

125. The plastic film according to any one of claims 107 to 124, wherein the second surface coating (i) is adhesive and has a basis weight of at most 5.0 g / m 2 , preferably not more than 4.0 g / m 2 , more preferably not more than 3.0 g / m 2 , most preferably not more than 2.0 g / m 2 and in particular not more than 1.0 g / m 2 or (ii) is adhesive and has a surface weight of not more than 100 g / m 2 , preferably not more than 80 g / m 2 , more preferably not more than 60 g / m 2 , preferably not more than 40 g / m 2 and in particular not more than 20 g / m 2 has.

126. The plastic film according to any one of the preceding claims, which is between (i) a layer, preferably any layer, containing or based on polyolefin; and (ii) a layer, preferably any layer, containing or based on polyamide and / or polyester; comprising at least one layer containing or based on water-soluble polymer.

127. The plastic film according to any one of the preceding claims, which (i) comprises or consists of layer (a), layer (b) and layer (d); wherein layer (b) is preferably arranged between layer (a) and layer (d); preferably is in direct contact with layer (a) and / or with layer (d); wherein layer (b) preferably contains, in addition to the functionalized polyolefin, further polymers, preferably water-soluble polymer, preferably the same water-soluble polymer which is contained in layer (c); or (ii) comprises or consists of layer (a), layer (b), layer (c) and layer (d); wherein layer (b) is preferably arranged between layer (a) and layer (c); preferably is in direct contact with layer (a) and / or with layer (c); wherein layer (b), based on the total weight of layer (b), preferably contains at most 10 wt.% water-soluble polymer, more preferably 5 wt.%, even more preferably at most 2.5 wt.%, most preferably at most 1.0 wt.%, and in particular contains practically no water-soluble polymer.

128. The plastic film according to any one of the preceding claims, which - the layer (a); - layer (b); and - the layer (d); comprises or consists of.

129. The plastic film according to claim 128, wherein layer (b) is arranged between layer (a) and layer (d); preferably, it is in direct contact with layer (a) and / or layer (d).

130. The plastic film according to any one of the preceding claims, which - the layer (a); - the layer (b); - the layer (d); and - the layer (f); comprises or consists of.

131. The plastic film according to claim 130, wherein layer (d) is arranged between layer (b) and layer (f); preferably, it is in direct contact with layer (b) and / or layer (f).

132. The plastic film according to any one of the preceding claims, which - the layer (a); - the layer (b); - the layer (d); - the layer (f); and - which comprises or consists of layer (g).

133. The plastic film according to claim 132, wherein layer (f) is arranged between layer (d) and layer (g); preferably, it is in direct contact with layer (d) and / or with layer (g).

134. The plastic film according to any one of the preceding claims, which - the layer (a); - the layer (b); - layer (c); and - the layer (d); comprises or consists of.

135. The plastic film according to claim 134, wherein layer (b) is arranged between layer (a) and layer (c); preferably, it is in direct contact with layer (a) and / or layer (c).

136. The plastic film according to claim 134 or 135, wherein layer (c) is arranged between layer (b) and layer (d); preferably, it is in direct contact with layer (b) and / or layer (d).

137. The plastic film according to any one of the preceding claims, which - the layer (a); - the layer (b); - the layer (c); - the layer (d); and - the layer(s); comprises or consists of.

138. The plastic film according to claim 137, wherein layer (d) is arranged between layer (c) and layer (e); preferably, it is in direct contact with layer (c) and / or layer (e).

139. The plastic film according to any one of the preceding claims, which - the layer (a); the layer (b); - the layer (c); - the layer (d); - the layer(s); and - the layer (f); comprises or consists of.

140. The plastic film according to claim 139, wherein layer (e) is arranged between layer (d) and layer (f); preferably, it is in direct contact with layer (d) and / or with layer (f).

141. The plastic film according to any one of the preceding claims, which - the layer (a); - the layer (b); - the layer (c); - the layer (d); - the layer(s); - the layer (f); and - the layer (g); comprises or consists of.

142. The plastic film according to claim 141, wherein layer (f) is arranged between layer (e) and layer (g); preferably, it is in direct contact with layer (e) and / or layer (g).

143. The plastic film according to any one of the preceding claims, wherein the plastic film has a layer structure selected from (i) (a)-(d); (n) (a)-(b)-(c); (a)-(b)-(d); (a)-(b)-(e); (a)-(b)-(f); (a)-(b)-(g); (a)-(c)-(d); (a)-(c)-(e); (a)-(c)-(f); (a)-(c)-(g); (a)-(d)-(g); (a)-(d)-(e); (a)-(d)-(f); (in) (a)-(b)-(c)-(d); (a)-(b)-(c)-(e); (a)-(b)-(c)-(f); (a)-(b)-(c)-(g); (a)-(b)-(d)-(e); (a)-(b)-(d)-(f); (a)-(b)-(d)-(g); (iv) (a)-(b)-(c)-(d)-(e); (a)-(b)-(c)-(d)-(f); (a)-(b)-(c)-(d)-(g); (a)-(b)-(c)-(f)-(g); (a)-(b)-(d)-(f)-(g); (a)-(c)-(d)-(e)-(g); (v) (a)-(b)-(c)-(d)-(e)-(g); (a)-(b)-(c)-(d)-(f)-(g); (a)-(b)-(c)-(e)-(f)-(g); and (vi) (a)-(b)-(c)-(d)-(e)-(f)-(g).

144. The plastic film according to any one of the preceding claims, wherein the plastic film is cleavable along the at least one layer which contains or is based on water-soluble polymer when treated in a water bath, optionally at elevated temperature and after a sufficient exposure time.

145. The plastic film according to any one of the preceding claims, wherein the water-soluble polymer has a water solubility of at least 5.0 g / L; more preferably at least 10 g / L, even more preferably at least 15 g / L, most preferably at least 20 g / L, and especially at least 25 g / L.

146. The plastic film according to any one of the preceding claims, wherein the non-water-soluble polymer has a water solubility of at most 1000 mg / L; more preferably at most 500 mg / L, even more preferably at most 100 mg / L, most preferably at most 50 mg / L, and especially at most 10 mg / L.

147. A process for producing a plastic film according to any one of the preceding claims by blown film coextrusion.

148. The method of claim 147, wherein the extrusion of the plastic film occurs in one step.

149. A plastic film obtainable by a process according to claim 147 or 148.

150. Use of a plastic film according to one of claims 1 to 146 for recycling a part of its components, wherein the plastic film is preferably split after or during the treatment in a water bath, optionally at elevated temperature and after a sufficient exposure time, along at least one layer which contains or is based on water-soluble polymer.

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