MULTILAYER FILM, PROCESS FOR PREPARING IT, LAMINAR STRUCTURE, CONTAINER AND PACKAGED ARTICLE

Abstract

The present invention relates to a film for packaging a product, particularly an improved multilayer film containing recycled polyolefin. One of the objectives of the present invention is to provide a flexible multilayer film incorporating higher levels of recycled high-density polyethylene resin. The inventors have found that at least one of the aforementioned objectives is achievable with a multilayer film having a first polyethylene layer, a second polyethylene sealing layer, and, between them, a middle layer containing recycled HDPE.

Description

MULTILAYER FILM Field of invention The present invention relates to a film for packaging a product, particularly an improved multilayer film that has recycled polyolefin. Background of the invention Plastics are used in a wide variety of applications, such as packaging and consumer goods. Plastics are in high demand in these applications due to their relatively low production costs and the good balance of material properties. To meet growing demand, millions of tons of plastic are produced worldwide. Most of these synthetic plastics are made from increasingly scarce fossil fuels, such as oil and natural gas. Producing plastic from fossil fuels contributes to rising greenhouse gas emissions. The ubiquitous use of plastics has resulted in millions of tons of plastic waste being generated each year. Most used plastic ends up in landfills, some as litter, and some in waterways. The industry is under environmental pressure to recycle polymer waste, especially that used in packaging applications. Plastic recycling has emerged as a solution to mitigate this pressure. 1796856 of 54 the problems associated with the widespread use of plastics. Individual or mixed streams of plastic waste are sorted, washed and reprocessed into pellets suitable for reuse in plastics processing. Post-consumer resin includes, in particular, a large amount of high-density polyethylene (HDPE), primarily due to its extensive use in large containers, such as milk cartons, household cleaning bottles, and personal care bottles. The post-consumer recycled resin from these containers contains contaminants like paper and other plastic resins, making it difficult to incorporate post-consumer recycled HDPE into new packaging. In the past, attempts have been made to incorporate recycled polyethylene into packaging material. One such container made with recycled HDPE is described in EP0561187 A1 (Owen Illinois Plastic Products Inc., 1993), which discloses a plastic container manufactured from a melt blend of a post-consumer resin and virgin ethylene polymers. The blend includes a post-consumer high-density polyethylene homopolymer plastic resin and a small amount of linear low-density polyethylene resin, preferably along with virgin HDPE, to provide increased resistance to stress cracking and to counteract the loss of physical properties due to the presence of post-consumer resins. 1796856 of 54 Multilayer flexible film structures are known to be made with different materials to provide different functions. These structures offer good properties. Typically, multilayer film structures include a combination of two polyethylene layers. However, these multilayer films usually utilize virgin polymers. In flexible packaging, which includes films or laminates for making bags or pouches and films for making tubes, polyethylene film is a crucial raw material. Depending on the package size, polyethylene can account for up to 95% of flexible packaging. Therefore, there is a desire to increase the incorporation of recycled polyethylene in multilayer flexible films. Specifically, the aim is to provide a multilayer flexible film with increasing levels of mechanically recycled polyethylene to promote a circular economy. However, current inventors have discovered that the use of recycled polyethylene, more specifically mechanically recycled polyethylene, in flexible films and packaging materials is limited due to quality issues, including gel formation, reduced mechanical strength, and sealing problems. In addition to these quality issues, the incorporation of recycled polyethylene also causes orange peel on the print face, film tearing, and leaks in the packaging. When blown film is manufactured with recycled polymer material, the following problems arise: 1796856 of 54 post-consumer, the films have diminished physical properties. To minimize these limitations, the incorporation level in known multilayer films of recycled polyethylene, especially mechanically recycled polyethylene, has been kept below 10% by weight. Among the objectives of the present invention, it is desired to provide a flexible multilayer film that incorporates higher levels of recycled high-density polyethylene resin. Another objective of the present invention is to provide a flexible multilayer film that incorporates a greater amount of recycled polyethylene without compromising mechanical and functional properties. Another object of the present invention is to provide a process for preparing an extrusion-blown flexible multilayer film that ensures the maintenance of good film quality even when incorporating higher levels of recycled polyethylene content. It is also an object of the present invention to provide a laminate having a flexible multilayer film that incorporates a higher amount of recycled polyethylene without compromising the mechanical and functional properties of the laminate structure. Another object of the present invention is to provide a flexible container that allows for greater recycling and is suitable for the circular economy. 1796856 of 54 Summary of the invention The present inventors have discovered that at least one of the aforementioned objectives can be achieved by means of a multilayer film having a first layer of polyethylene, a second layer of sealing polyethylene, and, between them, a central layer of recycled HDPE. The present inventors have further discovered that limiting the amount of LLDPE and LDPE in the central layer further improves the functional and mechanical properties of the multilayer film, even when higher levels of recycled HDPE are included in the film. As used in this document, the term “recycled” polyethylene includes post-consumer recycled (PCR) polyethylene. Recycled polyethylene can be either mechanically recycled or chemically recycled. As used herein, the term “post-consumer recycled” (PCR) refers to resin (e.g., a polymer or polymers) that has reached the intended end user or consumer, is no longer used for its intended purpose, and has been collected or recovered after disposal by the end user or consumer. Thus, for example, the term is understood to refer to material that would otherwise have been disposed of as waste but has instead been collected and recovered (regenerated) as input material, rather than new virgin material, for a recycling or manufacturing process. The expression includes these collected or recovered materials that have been 1796856 of 54 treated or processed to facilitate the reuse of the material. The term recycled includes polyethylene that has been used and subsequently entered an established recycling stream. As used in this document, the term recycled high-density polyethylene (rHDPE) refers to post-consumer recycled high-density polyethylene resin comprising high-density polyethylene homopolymer. Preferably, recycled high-density polyethylene is prepared from rigid bottles, including milk bottles, juice bottles, and other consumer bottles, such as household and personal care product bottles; preferably, 95% of the recycled HDPE consists of milk bottles, juice bottles, and other consumer bottles. Preferably, the level of virgin HDPE resin is less than 3% by weight, and preferably no virgin HDPE resin is added. The term “virgin polyethylene,” as used herein, denotes polyethylene that has not been used by an end consumer / user and subsequently recycled. “Virgin polyethylene” is a polymeric material that has not been subjected, or otherwise processed, to a heat or molding process. The physical, chemical, and flow properties of recycled polymer resin (PCR) differ from those of virgin polymeric resin. Polyethylene includes LDPE, LLDPE, and HDPE. 1796856 of 54 In this document, the term “flexible film” refers to a flexible polymer sheet that is substantially thinner than it is wide and is primarily used to prepare packaging for storing consumer goods in solid, semi-solid, and / or liquid form. Flexible film may be supplied as a roll of wound material. It is commonly used to prepare bags, pouches, pouches, and other sealed packaging for consumer products. As used herein, the term “laminated structure” refers to film layers bonded together, in this case a multilayer film according to the present invention to a second polymeric film substrate. The bonding can be achieved by heat treatment, adhesives, or another method known in the art for laminating two films or sheets. According to a first aspect of the present invention, a multilayer flexible film for preparing a container is disclosed, said multilayer flexible film comprising: i) a first layer of polyethylene ii) a second layer of sealing polyethylene iii) a central layer sandwiched between the first layer of polyethylene and the second sealing layer of polyethylene; where the middle layer comprises at least 80% by weight of recycled HDPE. 1796856 of 54 According to a second aspect of the present invention, a process for preparing a flexible multilayer film by means of a blowing process is disclosed. According to a third aspect of the present invention, a laminate is disclosed comprising a multilayer film of the first aspect or a multilayer film obtained by a process of the second aspect. According to the fourth aspect of the present invention, a container formed from the laminate or multilayer film described herein is disclosed. The invention also includes a packaged article enclosing a consumer product. Detailed description of the invention According to the first aspect of the present invention, a flexible multilayer film is disclosed comprising a first polyethylene layer, a second polyethylene sealant layer, and a core layer sandwiched between the first polyethylene layer and the second polyethylene sealant layer. The core layer comprises at least 80% by weight of recycled HDPE. Multilayer film The term “multilayer film” refers to a film comprising at least three layers. Preferably, the multilayer film includes a “skin layer,” a term referring to an outer layer of the multilayer film. Typically, a multilayer film comprises two skin layers, which may be the same or different in composition. 1796856 of 54 “Layer” refers to a single thickness, coating, or stratum that extends over or covers a surface. The multilayer film according to the present invention is a coextruded film formed by coextruding the three layers of the multilayer film. The multilayer film according to the first aspect of the present invention has at least a three-layer structure. Preferred embodiments may have more than three layers, for example, five layers, seven layers, or more. Preferably, the multilayer film has a thickness ranging from 5 micrometers to 250 micrometers. More preferably, the thickness of the multilayer film ranges from 30 micrometers to 250 micrometers. The middle layer can have a thickness of at least 8 micrometers, preferably at least 12 micrometers, more preferably at least 14 micrometers, but preferably no more than 175 micrometers, preferably no more than 150 micrometers, and preferably no more than 100 micrometers. In some embodiments, the first layer is an outer layer of a container and the second layer is an inner layer; that is, the first and second layers are the "skin" on the top and bottom (in cross-section) of the film. Ideally, the multilayer film should be unstretched. By "unstretched," it is meant that the multilayer film is not dimensionally stretched as is done in the case of biaxially oriented films. Therefore, it is preferred that the multilayer film, according to 1796856 of 54 This invention is not biaxially or uniaxially stretched. Stretching, as used herein, is a processing step that stretches the film more than a film stretches due to the normal stretching effects caused by film manufacturing. For example, a film on a cast film line is stretched and thus slightly stretched in the machine direction. A similar effect occurs on a blown film line where the bubble is stretched. However, these stretching effects are not understood as stretching. Stretching is something more than the stretching that occurs on the cast film line or the blown film line. Accordingly, the inventive multilayer film is not stretched, and therefore, the multilayer film according to this invention is either a cast film or a blown film, the latter being preferred.In the case that the multilayer film is produced on a blown film line, the cooling of the multilayer film can be done by water cooling or by air cooling, the latter being preferred. Preferably, the multilayer film is blow-molded, more preferably by a blow-film coextrusion process, where the molten polymer materials for the first polyethylene layer, the core layer, and the second polyethylene sealing layer, and optionally for all other layers, are extruded and then passed through an annular die and blown into a tubular film, forming a bubble that collapses between pressure rollers after solidification. The blow-film coextrusion can preferably be carried out at a temperature 1796856 of 54 between 160 °C and 240 °C, and cooled with water or, preferably, with blow gas (generally air) to a temperature of 10 to 50 °C to provide a freeze-line height of 0.5 to 8 times the disc diameter. The blow ratio should generally be in the range of 1.5 to 4.0, such as 2.0 to 4.0, preferably 2.5 to 3.5. Optionally, one or both surfaces of the multilayer blown film can be treated by corona or flame using one of the known methods. For corona treatment, the film is passed between two conductive elements that serve as electrodes. A voltage so high, typically alternating current (around 10,000 V and 10,000 Hz), is applied between the electrodes that spray or corona discharges can occur. Due to the spray or corona discharge, the air above the film surface is ionized and reacts with the film's surface molecules, causing the formation of polar inclusions in the essentially non-polar polymer matrix. Treatment intensities are within the usual range, preferably 3 to 4 dynes / cm² after production. The multilayer film may be in the form of a film or sheet. The multilayer film or sheet may preferably be laminated or coextruded with another web to form additional layers. The multilayer film or sheet, either on its own or after lamination with other layers, may be formed into a bag, sack, envelope, gusseted container, tube, or any other form of flexible packaging known to a person skilled in the art. 1796856 of 54 First layer of polyethylene The multilayer film disclosed according to the first aspect includes a first polyethylene layer. The first polyethylene layer is preferably composed of LLDPE, LDPE, or combinations thereof. Preferably, the first polyethylene layer includes virgin LLDPE, virgin LDPE, or combinations thereof. It is also preferred that the first polyethylene layer includes chemically recycled LLDPE, chemically recycled LDPE, or combinations thereof. It is also preferred that the polyethylene be a combination of virgin and chemically recycled material. Preferably, the amount of HDPE present in the first polyethylene layer is less than 10% by weight, and even more preferably, less than 5% by weight, and still more preferably, less than 3% by weight of the first polyethylene layer. Most preferably, the first polyethylene layer is practically free of HDPE. That is, the first polyethylene layer includes 0% by weight of HDPE, preferably less than 0% by weight of mechanically recycled HDPE. The HDPE may include virgin HDPE, chemically recycled HDPE, and mechanically recycled HDPE. Preferably, the first polyethylene layer comprises between 0% and 3% by weight of recycled HDPE, virgin HDPE, or mixtures thereof by weight of the first polyethylene layer, and still preferably 0% by weight of recycled HDPE, virgin HDPE, or mixtures thereof by weight of the first polyethylene layer.Without wanting to be limited by theory, it is believed that in the multilayer film according to the present invention that. 1796856 of 54 incorporates high levels of recycled HDPE in the core layer. The presence of recycled HDPE, virgin HDPE, or mixtures thereof in the first polyethylene layer at a level exceeding 3% by weight of the first layer has an adverse effect on film strength due to gel formation, leading to processing defects. Furthermore, this adverse effect is particularly pronounced when the first polyethylene layer includes recycled LLDPE or recycled LDPE, and more specifically when recycled LLDPE is present. Preferably, the first polyethylene layer has a combination of LDPE and LLDPE. Preferably, the first polyethylene layer includes 20 to 100 parts by weight of LLDPE, more preferably 80 to 100 parts by weight of LLDPE and 0 to 50 parts by weight of LDPE, more preferably 0 to 20 parts by weight of LDPE. Preferably, the first polyethylene layer comprises 50% to 100% by weight of recycled LLDPE, recycled LDPE, or mixtures thereof.It is also preferable that the first layer comprises at least 60% by weight, preferably 70% by weight, preferably at least 75% by weight, but normally not more than 99% by weight, preferably not more than 90% by weight, preferably not more than 80% by weight of recycled LLDPE, recycled LDPE or mixtures thereof, by weight of the first polyethylene layer. Preferably, the first polyethylene layer has a substantially less thickness than the thickness of layer 13 1796856 of 54 central and substantially less than the total multilayer film thickness. Preferably, the thickness of the first polyethylene layer is substantially less, normally less than 35% of the multilayer film thickness. Preferably, the first polyethylene layer comprises between 10% and 40% by weight of the total weight of the multilayer film, and even more preferably between 15% and 30% by weight of the total weight of the multilayer film. Linear low-density polyethylene (LLDPE): Linear low-density polyethylene (or LLDPE) is a linear ethylene / β-olefin copolymer containing a heterogeneous distribution of short-chain branches comprising ethylene-derived units and units derived from at least one C3-C10 β-olefin comonomer. LLDPE is characterized by little or no long-chain branching, unlike conventional LDPE. LLDPE has a density of 0.910 g / cc to less than 0.940 g / cc. Non-limiting examples of LLDPE include TUFLIN™ linear low-density polyethylene resins (available from The Dow Chemical Company), DOWLEX™ polyethylene resins (available from The Dow Chemical Company), FINGERPRINT™ polyethylene resins (available from The Dow Chemical Company), and MARLEX™ polyethylene (available from Chevron Phillips). The linear low-density polyethylene (LLDPE) present in the multilayer film according to the present invention has a density in the range of 0.890 to 0.925 g / cm3, more preferably in the range of 0.900 to 1796856 of 54 0.925 g / cm3, even more preferably in the range of 0.910 to 0.923 g / cm3, even more preferably having a density in the range of 0.915 to 0.922 g / cm3. Linear low-density polyethylene (LLDPE) preferably includes at least one comonomer, preferably one or two, the latter being especially preferred. Said comonomer(s) is / are preferably (a) C3 to C10 α-olefin comonomer(s). Therefore, the use of copolymers with a single comonomer or terpolymers, i.e., copolymers of ethylene with two other comonomers, is especially preferred. Said terpolymer is a specifically preferred linear low-density polyethylene (LLDPE). Therefore, linear low-density polyethylene (LLDPE) preferably contains only one or two types of C3 to C10 α-olefin comonomer(s). Even more preferably, the comonomer(s) are selected from the group consisting of 1-butene, 1-hexene, 1-octene, and mixtures thereof. In a preferred embodiment, the comonomer employed is 1-octene.In another preferred embodiment, linear low-density polyethylene (LLDPE) is a terpolymer made up of ethylene, 1-butene, and 1-hexene. The amount of α-olefin comonomer(s) present in linear low-density polyethylene (LLDPE) can range from 1.0 to 10.0 mol%, as well as from 1.5 to 5.0 mol%, or from 2.0 to 4.0 mol%. If the linear low-density polyethylene (LLDPE) is a terpolymer composed of ethylene, 1-butene, and 1-hexene, it is preferred that the 1-butene content be in the range of 0.1 to 1.0 mol% and the 1-hexene content in the range of 2.0 to 3.5 mol%. 1796856 of 54 Preferably, linear low-density polyethylene (LLDPE) has an MFR2 melt flow index (190 °C, 2.16 kg) of the order of 0.15 to 8.0 g / 10 min, more preferably of the order of 0.15 to 4.0 g / 10 min, more preferably of the order of 0.15 to 2 g / 10 min, more preferably of the order of 0.3 to 1 g / 10 min and even more preferably of the order of 0.5 to 1 g / 10 min. The linear low-density polyethylene (LLDPE) of the invention has a density preferably in the range of 0.91 g / mL to 0.93 g / mL, preferably in the range of 0.92 to 0.93 g / mL, and especially 0.925 g / mL. The LLDPE has a melting point preferably less than 2.0 and preferably less than approximately 1.0 g / 10 minutes. The LLDPE used in the present invention has long linear chains with a controlled number of relatively short chain branches attached to the linear chain along its entire length. These side chains or branches are short and preferably contain from 1 to 10 carbon atoms, depending on the alpha-monoolefin used in the polymer preparation.Linear low-density polyethylene differs structurally from low-density polyethylene manufactured by high-pressure free-radical-initiated polymerizations in that it has few, if any, long-chain branches. Linear low-density polyethylene is commercially available from multiple suppliers. One technique for preparing such polymers involves copolymerizing ethylene and butene in the phase 1796856 of 54 of vapor in a fluidized bed process. Due to the limitations imposed by the way in which the polymerization is carried out in the vapor phase, the ethylene polymers prepared by this process are limited to ethylene-butene copolymers. Operating in solvent systems, copolymers can be prepared from alpha-monoolefin comonomers containing up to 12 carbon atoms. Preferably, linear low-density polyethylenes are ethylene copolymers that have polymerized in them at least one alpha-monoolefin comonomer containing 6 to 12 carbon atoms, and that optionally also have butene copolymerized in them. Preferably, the linear low-density polyethylene present in the multilayer film is virgin LLDPE or chemically recycled LLDPE. Preferably, it is virgin LLDPE. Other embodiments use mechanically recycled LLDPE. Preferably, the linear low-density polyethylene (LLDPE) present in the multilayer film according to the present invention is a butene comonomer-based LLDPE, preferably without antiblocking additives. Preferably, it includes anti-slip additives. A preferred commercially available LLDPE is Relene® F18010 from Reliance Industries Limited, India. This is a butene comonomer-based LLDPE with optimal levels of antioxidants. The LLDPE preferably has a density of 0.918 g / cm³ (ASTM D5105) and a melt flow rate (MFR) at 190°C, 2.16 kg of 0.9 g / 10 min (ASTM D1238). 1796856 of 54 Low-density polyethylene (LDPE): The first polyethylene layer preferably includes a low-density polyethylene (LDPE). Low-density polyethylene (or LDPE) consists of an ethylene homopolymer, or an ethylene / α-olefin copolymer comprising at least one C3 to C10 α-olefin, having a density preferably of 0.915 g / cc to less than 0.940 g / cc and containing long-chain branches with a wide molecular weight distribution (MWD). LDPE is typically produced by high-pressure free-radical polymerization (tubular reactor or autoclave with a free-radical initiator). Non-limiting examples of LDPE include MarFlex™ (Chevron Phillips), LUPOLEN™ (Lyondell Gasell), as well as LDPE products from Borealis, Ineos, ExxonMobil, and others. Low-density polyethylene (LDPE) is known in the art. Preferably, low-density polyethylene (LDPE) has a melt flow index (MFR2) (at 190 °C, 2.16 kg) in the range of 0.05 to 2.0 g / 10 min, more preferably in the range of 0.10 to 1.8 g / 10 min, and even more preferably in the range of 0.15 to 1.5 g / 10 min. Accordingly, an example of such low-density polyethylene (LDPE) is the commercial product FT5230 from Borealis AG. In addition to LDPE and / or LLDPE, the first polyethylene layer may optionally include additional ingredients such as antioxidants, light stabilizers, acid sequestrants, processing aids, antiblocking agents, nucleating agents, and slip agents. Such additives 18 1796856 of 54 are known in the art, see, for example, Hans Zweifel in “Plastics Additives Handbook”, 6th edition, and do not contribute to the invention. Preferably, the low-density polyethylene present in the multilayer film is virgin LDPE or chemically recycled LDPE. Preferably, it is virgin LDPE. Some embodiments contain mechanically recycled LDPE. Preferably, the low-density polyethylene (LDPE) present in the multilayer film according to the present invention includes anti-slip additives. A commercially available LLDPE is preferably Relene® 1020FA20 from Reliance Industries Limited, India. The LDPE preferably has a density of 0.920 g / cm³ (ASTM D792) and a melt flow rate (MFR) at 190°C, 2.16 kg of 2.0 g / 10 min (ASTM D792). D1238). These values ​​were measured for a 40 micrometer film manufactured with 0.7 mm die spacing and 2.5 BUR. Second polyethylene sealing layer According to the first aspect of the present invention, the multilayer film includes a second polyethylene sealing layer. The term "sealing layer," as used herein, is understood to mean that this layer can be used for sealing purposes; that is, sealing can take place on the surface of this layer or on a portion thereof. This layer is generally sealed when the multilayer film or a laminate composed of the multilayer film is converted into a 1796856 of 54 container to hold consumer products, for example, a composition for clothing. The sealing layer forms one of the two outer surfaces of the multilayer film. Even more preferably, the sealing layer is bonded, i.e., attached to the middle layer of the multilayer film. Ideally, the sealing layer is substantially thinner than the core layer and substantially thinner than the total multilayer film thickness. Ideally, the sealing layer is substantially thinner, typically less than 35% of the multilayer film thickness. The second polyethylene sealing layer preferably includes LLDPE, LDPE, or combinations thereof. Preferably, the second polyethylene sealing layer includes virgin LLDPE, virgin LDPE, or combinations thereof. It is also preferable that the second polyethylene layer includes chemically recycled LLDPE, chemically recycled LDPE, or combinations thereof. It is also preferable that the polyethylene be a combination of virgin and chemically recycled material. Preferably, the amount of HDPE present in the second polyethylene sealing layer is less than 10% by weight, and even more preferably less than 5% by weight, and still more preferably less than 3% by weight of the second polyethylene sealing layer, and most preferably the second polyethylene sealing layer contains no HDPE. That is, the second polyethylene sealing layer includes 20 1796856 of 54, 0% by weight of HDPE, preferably less than 0% by weight of mechanically recycled HDPE. The HDPE may include virgin HDPE, chemically recycled HDPE, and mechanically recycled HDPE. Preferably, the second polyethylene sealing layer comprises between 0 and 3% by weight of recycled HDPE, virgin HDPE, or mixtures thereof, although preferably 0% by weight of recycled HDPE, virgin HDPE, or mixtures thereof. Preferably, the second polyethylene sealant layer comprises LDPE, LLDPE, m-LLDPE, and, more preferably, a combination of LLDPE and LDPE, and even more preferably, a combination of m-LLDPE and LDPE. Preferably, the second polyethylene layer comprises 20 to 100 parts, more preferably 50 to 100 parts, and even more preferably 80 to 100 parts by weight of LLDPE and / or m-LLDPE, and 0 to 80 parts by weight, more preferably 0 to 50 parts, and even more preferably 0 to 20 parts by weight of LDPE. More preferably, the LLDPE of the second polyethylene sealant layer comprises metallocene-catalyzed LLDPE (m-LLDPE). The details of LDPE and LLDPE that have been discussed previously with respect to the first polyethylene layer are also suitable for the second polyethylene sealing layer. Preferably, the second polyethylene sealing layer includes a combination of m-LLDPE and LDPE. 1796856 of 54 Metallocene-catalyzed polyethylene (m-LLDPE): Metallocene-catalyzed linear low-density polyethylene (or m-LLDPE) consists of linear ethylene / α-olefin copolymers containing a homogeneous distribution of short-chain branches comprising ethylene-derived units and units derived from at least one C3-C10 α-olefin comonomer, or at least one C4-Cs α-olefin comonomer, or at least one Ce-Cs α-olefin comonomer. m-LLDPE has a density of 0.913 g / cc to 0.940 g / cc. Preferably, the density is at least 0.918 g / cc, and preferably at least 0.920 g / cc, but preferably not more than 0.938 g / cc, and preferably not more than 0.925 g / cc. Non-limiting examples of m-LLDPE include EXCEED™ metallocene PE, ENABLE® mPE (available from ExxonMobil Chemical), LUFLEXEN™ m-LLDPE (available from LyondellBasell), and ELTEX™ PF m-LLDPE (available from LyondellBasell). Ineos Olfeins & Polymers). Ideally, the metallocene-catalyzed linear low-density polyethylene present in the multilayer film is either virgin m-LLDPE or chemically recycled m-LLDPE. Virgin m-LLDPE is preferable. For example, Exceed™ 1018MK is a metallocene-catalyzed ethylene-1-hexene copolymer from ExxonMobil Chemical that has a density of 0.918 g / cc and a melt flow rate of 1 g / 10 minutes (at a 2.16 kg charge and a temperature of 190 °C). It has an antiblocking level of 5000 ppm and a slip level of 1000 ppm. 1796856 of 54 For example, ELITE™ 5401 G is a metallocene-catalyzed LLDPE that has a density of 0.918 g / cc (ASTM D792) and a melt index of 1 g / 10 minutes (at 2.16 Kg load and a temperature of 190 °C, ASTM D1238). Preferably, the second polyethylene sealing layer comprises 10 to 40% by weight of the total weight of the multilayer film, and even more preferably 15 to 30% by weight of the total weight of the multilayer film. middle layer As previously defined, the multilayer film of this invention comprises a core layer. The core layer is sandwiched between the first polyethylene layer and the second polyethylene sealing layer. By the term "core layer," as used herein, it is understood that this layer forms the central part of the multilayer film and contributes particularly to its mechanical and / or optical properties. However, in this case, the specific selection of the core layer further improves the sealing performance of the sealing layer(s). The term "core layer" also indicates that this layer is typically the thickest in the multilayer film. Therefore, it is preferred that the thickness of the central layer be in the range of 5 to 150 micrometers, more preferably in the range of 10 to 125 micrometers, and even more preferably in the range of 10 to 100 micrometers. 1796856 of 54 Furthermore, although the phrase "core layer" is singular, it can refer to one or more layers, such as between two and five layers—that is, two, three, four, or five layers—which together form the core layer of the multilayer film. However, each of the layers that together form the core layer is chemically identical; that is, they have been produced from the same material or composition. Thus, for this reason, the core layer is singular, although in some embodiments the core layer may comprise several layers, all produced from the same material, which is defined in more detail below. Recycled high-density polyethylene (rHDPE): The disclosed multilayer film includes recycled HDPE in the core layer. The core layer includes at least 80% by weight of recycled HDPE. More preferably, between 80% and 100% by weight of the core layer is recycled HDPE. Preferably, the amount of recycled HDPE by weight of the core layer is at least 81% by weight, preferably at least 83% by weight, preferably at least 84% by weight, but preferably not more than 99% by weight, preferably more than 95% by weight, preferably not more than 90% by weight, preferably not more than 85% by weight. The recycled high-density polyethylene (rHDPE) according to the present invention may include from 0% to 10% by weight of polypropylene, preferably from 0% to 7% by weight, and even more preferably from 1% to 2% by weight, wherein the polypropylene has a specific gravity ranging from 0.88 g / mL to 0.98 g / mL (ASTM D792, ASTM D1505). It is highly preferable that the recycled HDPE 24 1796856 of 54 according to the present invention has at least 90% by weight of HDPE with a melt flow index (MFI) of up to 2 g / mL (when measured at 190 °C and 2.16 Kg) and a density ranging from 0.94 gm / cc to 0.97 gm / cc. An example of recycled HDPE is the commercial grade KWR102 PCR (ex. KW Plastics). Recycled HDPE is generally inferior to virgin HDPE due to the presence of one or more contaminants. The presence of contaminants is one of the factors that reduces the functionality of recycled HDPE. One or more of the following typical contaminants that may be present in the recycled HDPE used in the core layer of the present invention include aluminum foil, silica, silicate, rubber, silicone, Teflon, fibrous material, cellulose, sealant, PET, oil / wax, inorganic dye, or combinations thereof. Typically, the recycled HDPE of the present invention includes a contaminant with an average particle size in the range of 1 micrometer to 100 micrometers. Recycled HDPE can be recycled chemically or mechanically. Preferably, recycled HDPE is recycled mechanically. As used here, the term “mechanically recycled” polyethylene denotes the processing of used polyethylene waste into a reusable raw material or by-product without significantly altering the resin’s chemical structure for further manufacturing. Mechanical recycling is the process where the polymer is shredded, remelted and reprocessed, re-blown, re-filmed and given different 1796856 of 54 forms. Mechanically recycled polyethylene undergoes at least one exposure to a thermal cycle (i.e., a melt-cool-remelt cycle). Exposure to the thermal cycle causes chain cleavage in the polyethylene, resulting in the formation of unsaturation (-C=C-). Unsaturation in the recycled polyethylene chain can be analyzed using the FT-IR peak analysis method (ASTM E168 and ASTM E1252). Unsaturation in mechanically recycled polyethylene can be measured using NMR 13C analysis (ASTM D537308). Mechanically recycled post-consumer polyethylene obtained from the remelting process results in unsaturation in the recycled polyethylene. The recycled polyethylene unit has unsaturation at at least one end. It is believed that the conditions during the recycling process cause the formation of unsaturation at the end of the polyolefin unit due to the disproportionate termination mechanism described below. HRH ψ polymer chain ..-M disproportion HHHH ------------R = Hipara PE 7 R = CH3paraPP (RH RH NC-CCC- polymer chain H ¿ A ar ' VAF polymer chain —cCC^C + RHRH polymer chain lili HHHH The mechanically recycled polyethylene unit has an unsaturation present at at least one end of the polyethylene. Preferably, at least 60% of the recycled polyethylene unit has an unsaturation present at at least one end. Still, preferably at least 70%, and even more 1796856 of 54 preferably at least 80%, more preferably at least 85%, even more preferably at least 90%, more preferably at least 95%, even more preferably at least 97% and most preferably 100% of the recycled polyethylene unit has an unsaturation present at at least one terminal end. More preferably, the recycled polyethylene unit has unsaturation present at both end segments. It is further preferred that at least 60% of the recycled polyethylene unit has unsaturation present at both end segments. Still more preferably, at least 70%, at least 80%, more preferably at least 85%, more preferably at least 90%, more preferably at least 95%, more preferably at least 97%, and more preferably 100% of the recycled polyethylene unit has unsaturation present at both end segments. Preferably, less than 10% by weight of the recycled polyethylene unit has an unsaturation at a position other than the terminal end of the polyethylene backbone chain, and even more preferably less than 5% by weight of the recycled polyolefin has an unsaturation present at a position other than the terminal end of the polyethylene backbone chain, even more preferably less than 3%, more preferably less than 1%, and most preferably the recycled polyolefin is free from any unsaturation at a position other than the terminal end of the recycled polyethylene backbone chain. 1796856 of 54 Mechanically recycled post-consumer polyethylene contains inorganic additives such as pigments and fillers that contribute to a higher ash / filler content in the recycled polyethylene. Mechanically recycled polyethylene has an ash content greater than 5% by weight, more preferably from 5% to 10% by weight, and even more preferably from 5% to 8% by weight. The ash content is measured using the standard methods ASTM D2584, ASTM D5630, and ISO 3451. Furthermore, chemically recycled post-consumer polyethylene is obtained through a repolymerization process, so it does not include an unsaturation in its chain and also has no fillers, and the ash content in chemically recycled post-consumer polyethylene is less than 1% by weight and, even so, it is preferable that the ash content be from 0% by weight to 1% by weight, and preferably from 0% by weight to 0.5% by weight. A more detailed review of mechanical recycling and other plastic recovery processes is described in SM Al-Salem, P. Lettieri, J. Baeyens, “Recycling and recovery routes of plastic solid waste (PSW): A review”, Waste Management, Volume 29, Issue 10, October 2009, Pages 2625-2643, ISSN 0956-053X. Although advances in mechanical recycling technology have improved the quality of recycled polymers to some extent, there are fundamental limitations in mechanical decontamination approaches, such as the physical entrapment of 1796856 of 54 contaminants (such as pigments) within a polymer matrix. Therefore, even with improvements in mechanical recycling technology, the dark color and high levels of chemical contamination in currently available recycled plastic waste prevent wider use of recycled resins by the plastics industry. “Mechanical recyclability”, with reference to a post-consumer used packaging material, means the ability to directly recycle a post-consumer used packaging material; wherein the recycling is carried out mechanically to rewrap the recycled material without having to: (1) pre-separate the different film layers of the used packaging material; (2) pre-clean the residual adhesive present in the used packaging material; and (3) add compatibilizers to the adhesive used to form the used packaging material. The recycled HDPE in the core layer has at least 50 mechanically recycled parts, more preferably at least 60 parts, even more preferably at least 70 parts, even more preferably at least 80 parts, and most preferably all the recycled HDPE in the core layer is mechanically recycled HDPE. Recycled HDPE is preferably a mechanically recycled, post-consumer rigid FMCG #2 HDPE container used for packaging household and personal care products. This includes, but is not limited to, fabric care products such as fabric softeners and laundry detergents. 1796856 of 54 hair oil, toilet cleaner, shampoos, conditioners, etc. Preferably, the post-consumer used bottles used to prepare the recycled HDPE do not include or have less than 10% of non-No. 2 rigid containers, such as those used to package pharmaceuticals, fertilizers, etc. HDPE preferably has properties within the ranges provided in the following table. Property Technical Values ​​Measurement Method (ASTM) Density 0.88 to 0.98 g / cc D 792 Melt Flow Rate (190 °C, 2.16 Kg) 0.3 to 0.7 g / 10 min D1238 Flexural Modulus 700 to 1200 MPa D790 Tensile Strength at Yield Limit 20 to 25 MPa D638 Material Color (Lab) Lref 33.47, aref — 5.75, bref -13.02 ΔE less than 5 RMS value of L,a,b Polypropylene Content Less than 10% by weight Contaminant present aluminum foil, silica, silicate, rubber, silicone, Teflon, material 1796856 of 54 Fibrous, cellulose, sealant, PET, oil / wax, inorganic dye, or combinations thereof. Melt screen size: 150 microns Virgin high-density polyethylene (HDPE): The middle layer may preferably include virgin HDPE. When present, the virgin HDPE constitutes between 0 and 3 l 20% by weight of the middle layer. Preferably, the amount of virgin HDPE by weight of the middle layer is at least 5% by weight, preferably at least 10% by weight, preferably at least 15% by weight, preferably at least 20% by weight of the middle layer. Virgin high-density polyethylene (or “HDPE”) is a an ethylene homopolymer or an ethylene / αolefin copolymer with at least one C4 to C10 α-olefin comonomer, or a C4 to C8 α-olefin comonomer, and a density of 0.0940 g / cc to 0.980 g / cc. Preferably, the density is at least 0.0945 g / cc, preferably at least 0.0950 g / cc, preferably at least 0.0953 g / cc, but preferably not greater than 0.975 g / cc, preferably not greater than 0.0970 g / cc, preferably not greater than 0.0965 g / cc, and furthermore 1796856 of 54 preferably not more than 0.0960 g / cc and preferably not more than 0.0955 g / cc. very HDPE can be a monomodal or multimodal copolymer. A “monomodal ethylene copolymer” is an ethylene / C4 to C10 α-olefin copolymer that has a distinct peak on gel permeation chromatography (GPC) showing the molecular weight distribution. A “multimodal ethylene copolymer” is an ethylene / C4 to C10 α-olefin copolymer that has at least two distinct peaks on GPC showing the molecular weight distribution. Multimodal includes copolymers with two peaks (bimodal) as well as copolymers with more than two peaks. Non-limiting examples of HDPE include DOW™ high-density polyethylene (HDPE) resins (available from The Dow Chemical Company), CONTINUUM™ bimodal polyethylene resins (available from The Dow Chemical Company), and LUPOLEN™ (available from The Dow Chemical Company). LyondellBasell), as well as HDPE products from Borealis, INEOS and ExxonMobil. Preferably, virgin HDPE has a melting index of less than about 0.5 g / 10 minutes, preferably less than 0.4 g / 10 minutes, and contains at least 98 mol% ethylene polymerized therein, any comonomer polymerized therein being an alpha-monoolefin containing between 3 and 12 carbon atoms. Such linear high-density ethylene polymers are known and reported in the art and are commercially available from numerous producers. Such linear high-density ethylene polymers are typically prepared by polymerizing ethylene, optionally in the presence of an alpha-monoolefin comonomer that 1796856 of 54 contains 4 to 12 carbon atoms in the presence of certain metallic catalysts such as chromium catalysts, for example, CrO3 supported on silica-alumina supports, and Ziegler-Natta catalysts, for example, TiCl3 used in conjunction with certain aluminum alkyl cocatalysts. The required density and desired melt index of the polymer are obtained by appropriate control of the polymerization conditions, including temperature, comonomer concentration under pressure, and the concentration of telegenerating agents such as hydrogen. HDPE is commercially available; for example, RELENE F46003 is a high-density polyethylene (HDPE) that has a density of 0.946 g / cc (ASTM D1505) and a melt index of 0.38 g / 10 minutes (with a 2.16 kg load and a temperature of 190 °C, ASTM D1238). Linear low-density polyethylene (LLDPE): Preferably, the core layer includes less than 20% LLDPE by weight, preferably less than 10% LLDPE by weight, preferably less than 5% LLDPE by weight, and most preferably less than 3% LLDPE by weight, and most preferably 0% LLDPE by weight is present in the core layer. This includes both recycled and virgin LLDPE. Preferably, when recycled LLDPE is present, it is chemically recycled, mechanically recycled, or a mixture of both. It is highly preferable that the middle layer be substantially free of LLDPE, i.e., that the middle layer has no added LLDPE. 1796856 of 54 deliberately, i.e., 0% by weight of LLDPE in the middle layer. Preferably, the middle layer includes 0 to 3% by weight of virgin LLDPE, by weight of the middle layer, preferably 0% by weight of virgin LLDPE. Preferably, the middle layer includes 0 to 3% by weight of recycled LLDPE, by weight of the middle layer, preferably 0% by weight of recycled LLDPE. Preferably, the core layer includes less than 20% by weight of LDPE, preferably less than 10% by weight of LDPE, preferably less than 5% by weight of LDPE, and most preferably, the LDPE levels in the core layer are less than 3% by weight, and most preferably, the LDPE present in the core layer is 0% by weight. This includes both recycled and virgin LDPE. When used, recycled LDPE is preferably chemically recycled LDPE, mechanically recycled LDPE, or mixtures thereof. It is highly preferable that the core layer contains no LDPE, i.e., that the core layer contains no deliberately added LDPE, i.e., 0% by weight of LDPE in the core layer. Preferably, the core layer includes between 0 and 20% by weight of virgin LDPE.Preferably, the middle layer includes 0 to 20% by weight of recycled LDPE, by weight of the middle layer, preferably 0% by weight of recycled LDPE. Preferably, the middle layer includes between 0 and 20% by weight of polyethylene selected from LLDPE, LDPE or mixtures thereof. 1796856 of 54 The middle layer may advantageously include typical additives (ADs) present in multilayer films, such as antioxidants, light stabilizers, acid scavengers, processing aids, antiblocking agents, nucleating agents, and slip agents. Such additives are known in the art (see, for example, Hans Zweifel in *Plastics Additives Handbook*, 6th edition) and do not contribute to the invention. Preferably, the middle layer is additive-free. Preferably, the middle layer comprises between 25% and 80% by weight of the total weight of the multilayer film, and even more preferably between 25% and 50% by weight of the total weight of the multilayer film. Multilayer film preparation process According to a second aspect of the present invention, a process is provided for preparing the multilayer film of the first aspect, wherein the film is manufactured by a blowing process, preferably an extrusion blowing process. The multilayer film is preferably formed by a coextrusion process (the simultaneous extrusion of multiple layers of material), for example, a blown film coextrusion process (which involves extruding a molten polymer tube through an annular die and inflating it to a size larger than its initial diameter to form a thin film bubble). The sheets can be formed, for example, using a sheet die. 1796856 of 54 The process preferably includes the step of maintaining the temperature of the extruder and the die for the middle layer within a range of 180 °C to 230 °C. Preferably, the die for extrusion is a circular die. Preferably, the process according to the present invention involves passing the molten extruded batch of the core layer through a filter screen to remove suspended particles. Preferably, the screen removes suspended particles with an average particle size by weight ranging from 1 to 180 micrometers in the melt. Multilayer film is preferably a blown film and is prepared by an extrusion-blow process well known to those skilled in the art. Ideally, the multilayer film can be obtained by a blown film coextrusion process. The term extrusion refers to a process in which a polymer or polymer blend is fed into an extruder and continuously propelled along a screw through regions of high temperature and pressure where the polymer melts and compacts, and is finally forced through a die. The extruder can be a single-screw extruder, a multi-screw extruder, a disc extruder, or a piston extruder. The process of preparing the multilayer film includes the step of adding the required amount of 1796856 of 54 polymer for each of the first, second, and middle layers in the extruder hopper. The polymers are then extruded along the extruder, where screws propel the polymer forward and simultaneously melt the polymers; the molten batch is then extruded through a die, preferably an annular or circular die. Preferably, during extrusion, the temperature of the extruder and the die through which the middle layer passes is maintained in the range of 180 °C to 230 °C. Preferably, the molten batch forming the middle layer of the multilayer film is further passed through a filter screen to remove suspended particles, where suspended particles with a weight average size ranging from 1 to 180 micrometers are removed from the molten batch.Next, the extruded mass is blown to create a bubble of the required thickness, and then a cooling process forms the multi-layer film that has a first layer of polyethylene, a second sealing layer of polyethylene with a middle layer that has recycled HDPE. Laminate A laminated structure having a multilayer film is described according to a third aspect of the present invention. In one embodiment of the present invention, a laminated structure is provided wherein a laminating layer is selected from a polyethylene layer and a polypropylene layer. The laminating layer is laminated to the multilayer film according to the present invention. The lamination layer, 1796856 of 54, is in contact with the first polyethylene layer of the multilayer film. Preferably, the lamination layer is a polyethylene layer or a polypropylene layer. In some embodiments, the lamination layer includes biaxially oriented polypropylene (BOPP). Preferably, the lamination layer is the printing layer. The lamination process involves the lamination stage of bonding the laminate layer to the multilayer film. Any of the commercially available techniques can be used for this lamination stage, including the use of a liquid adhesive (which can be solvent-based, solvent-free, or water-based); a hot melt adhesive; and thermal bonding. The laminate layer and the multilayer film can also be formed into a laminate using a coextrusion lamination process. Ideally, the laminated structure is printed at the interface between the lamination layer and the first polyethylene layer of the multilayer film. In some embodiments, it is also suitable to print the laminated structure on the surface. Suitable processes include the well-known flexographic and gravure printing techniques, which typically use nitrocellulose or water-based inks. Depending on the inks used and / or the applied layer weights, subsequent ink layers may be applied to build up sufficient opacity, either in flexographic or gravure printing. 1796856 of 54 The laminate according to the present invention preferably has a thickness ranging from 30 micrometers to 400 micrometers. More preferably from 40 micrometers to 300 micrometers. Container According to another aspect of the present invention, a container prepared from the multilayer film or laminate according to the invention is disclosed. The packaging may be in the form of a bag, sack, pouch, gusseted bag, stand-up pouch, tube, or other flexible packaging known in the art. The bags are preferably self-filling bags, and even more preferably filled using a vertical filling and sealing machine. The bags preferably have a capacity to hold from 1 gram to 1 kg of a composition. Preferably, the tube comprises the laminar structure with the laminar layer facing outwards and the multilayer film facing inwards and in close proximity to the product enclosed in the tube. Packaged item The container according to the present invention can be used to enclose a consumer product. The consumer product can be any product known in the art, such as, for example, a household care composition or a personal care composition. Non-limiting examples of household care compositions include compositions for the 1796856 of 54 Laundry cleaning, laundry care composition, laundry treatment composition, hard surface cleaning composition (for example, hard surfaces include tableware and bathroom surfaces, and house floors). Non-limiting examples of personal care compositions include hair care compositions, oral care compositions, and skin care compositions. The consumer product may be presented in any form known in the art, but is not limited to solids, particles, tablets, bars, gels, creams, emulsions, pastes, or unit-dose compositions. The unit-dose composition may preferably have a water-soluble pouch enclosing a composition that may be a solid, a gel, or a liquid. Preferably, the container according to the present invention is recyclable after use. Preferably, all layers of the container are made of polyethylene or an organic polyethylene-based blend, allowing for easy recycling through standard polyethylene recycling channels. Examples Example 1: Preparation of a multilayer film with different amounts of recycled HDPE in the middle layer. Two different multilayer films with a thickness of 30 micrometers were prepared. The multilayer films have the following structure: 1796856 of 54 Example of structure 1A: i) a first polyethylene layer had virgin LLDPE and virgin LDPE. The first layer constituted 30% by weight of the multilayer film. The first polyethylene layer was composed of 80% by weight of LLDPE (Relene® F18010, ex Reliance Industries Limited, India) and 20% by weight of LDPE (Relene®, 1020FA20 ex Reliance Industries Limited, India). (ii) The second polyethylene sealing layer constituted 30% by weight of the multilayer film. The polyethylene sealing layer was composed of 80% by weight of metallocene-catalyzed LLDPE (ExxonMobil's Exceed 1018 or Dow's Elite 5401G) and 20% by weight of LDPE (Relene®, 1020FA20 ex Reliance Industries Limited, India) relative to the total second polyethylene layer. The m-LLDPE has a density of 0.918 g / cc, MFR 0.9 g / 10 min, and the LDPE has a density of 0.92 g / cc and MFR 2 g / 10 min. iii) The middle layer constituted 40% by weight of the multilayer film according to the present invention. The middle polyethylene layer was composed of 80% by weight of recycled HDPE (rHDPE, Bayanan Nation Grade BP2120) and 20% by weight of LDPE (Relene®, 1020FA20 ex Reliance Industries Limited, India). Example of structure 1B: i) a first polyethylene layer with LLDPE and LDPE. The first layer constituted 25% by weight of the multilayer film. The first polyethylene layer was composed of 80 parts by weight of LLDPE (Relene® F18010, ex Reliance Industries Limited, India) and 20 parts of 1796856 of 54 weight of LDPE (Relene®, 1020FA20 ex Reliance Industries Limited, India). (ii) The second polyethylene sealing layer constituted 25% by weight of the multilayer film. The polyethylene sealing layer was composed of 80% by weight of metallocene-catalyzed LLDPE (ExxonMobil's Exceed 1018 or Dow's Elite 5401G) and 20% by weight of LDPE (Relene®, 1020FA20 ex Reliance Industries Limited, India) in the second layer. The m-LLDPE has a density of 0.918 g / cc, MFR 0.9 g / 10 min and the LDPE has a density of 0.92 g / cc and an MFR of 2 g / 10 min. iii) The middle layer constituted 50% by weight of the multilayer film. The polyethylene middle layer was composed of 40 parts by weight of recycled HDPE (rHDPE, Banyan Nation Grade BP2120), 50 parts by weight of virgin LLDPE (Relene® F18010, ex Reliance Industries Limited, India) and 10 parts by weight of LDPE (Relene®, 1020FA20 ex Reliance Industries Limited, India). Table 1a Example 1A (% wt) Example 1B (% wt) Acceptable Ranges First PE layer 30 25 Virgin LLDPE (by weight of first layer) 80 80 Virgin LDPE (by weight of first layer) 20 20 Middle layer 40 50 Recycled HDPE (by weight of middle layer) 80 40 1796856 of 54 Virgin LLDPE (by weight of the middle layer) 0 50 Virgin LDPE (by weight of the middle layer) 20 10 Second sealing PE layer 30 25 Metallocene-catalyzed LLDPE (by weight of the second layer) 80 80 Virgin LDPE (by weight of the second layer) 20 20 Multilayer film properties Tensile strength (N / 15 mm) MD 14.40 7.5 12 to 15 CD 11.39 5.2 9 to 12 Elongation (%) MD 587.35 113.6 540 to 740 CD 742.07 26.2 740 to 940 Young's modulus (N / mm2) MD 538.529 149 300 to 720 CD 479.22 160 490 to 790 The multilayer film in Example 1A showed good bubble stability during the blown film formation process; however, the film in Example 1B showed bubble instability with several processing defects, such as wrinkles and gels, during the blown film formation process. Example 1A showed superior mechanical and functional properties compared to Example 1B. The higher Young's modulus values ​​were also observed. 1796856 of 54 suggest that the multilayer film will have more resistance to elongation in use, the Young's modulus of the multilayer film according to the present invention was within acceptable ranges and during the formation of the bag it was stable and did not elongate, however the comparative multilayer film of Example 1B was more susceptible to elongation in use. Example 1C Structure: A multilayer film with a thickness of 30 micrometers was prepared. The multilayer film has a first layer of polyethylene containing LLDPE and LDPE. The first layer constituted 30% by weight of the multilayer film. The first polyethylene layer was composed of 80 parts by weight of LLDPE (Relene® F18010, ex Reliance Industries Limited, India) and 20 parts by weight of LDPE (Relene®, 1020FA20 ex Reliance Industries Limited, India). The second polyethylene sealing layer constituted 30% by weight of the multilayer film. This polyethylene sealing layer was composed of 80 parts metallocene-catalyzed LLDPE (ExxonMobil's Exceed 1018 or Dow's Elite 5401G) and 20 parts LDPE (Relene®, 1020FA20 ex Reliance Industries Limited, India). The LLDPE has a density of 0.918 g / cc and an MFR of 0.9 g / 10 min, while the LDPE has a density of 0.92 g / cc and an MFR of 2 g / 10 min. The middle layer constituted 40% by weight of the multilayer film. The polyethylene middle layer was composed of 40 parts virgin HDPE (Relene®, F46003 ex Reliance Industries Limited, India), 40 parts HDPE 1796856 of 54 recycled (rHDPE, Bayanan Nation Grade BP2120) and 20 parts LDPE (Relene®, 1020FA20 ex Reliance Industries Limited, India). Virgin HDPE has a density of 0.946 g / cc and an MFR of 0.38 g / 10 min. Table 1b Example Comp 1C* Tensile strength (N / 15mm) MD 12.6 CD 9.5 Elongation (%) MD 605.5 CD 871.6 *Multilayer film is excluded from the scope of the claim. It was observed that the multilayer film of Example 1C, with lower levels of recycled HDPE in the core layer, was comparable to Example 1A according to the present invention, which has higher levels of recycled HDPE in the core layer. It was also observed that even after the addition of a higher weight percentage of recycled HDPE, the mechanical properties of Example 1A were comparable to those of Example 1C. Example 2: Preparation of a multilayer film according to a preferred aspect of the present invention having recycled polyethylene in both the middle layer and the first polyethylene layer. According to a preferred aspect of the present invention, a multilayer film was prepared with a 1796856 of 54 thickness of 30 micrometers. The multilayer film (Example 2) has the following structure: (i) The first polyethylene layer constituted 25% by weight of the multilayer film and was composed of recycled LLDPE and recycled LDPE. The first polyethylene layer included 90% by weight of recycled LLDPE (Recycle-INrLL9110, ex INEOS) and 10% by weight of recycled LDPE (Recycle-INrLD23E760, INEOS) of the first polyethylene layer. (ii) The second polyethylene sealing layer constituted 25% by weight of the multilayer film. The polyethylene sealing layer was composed of 90% by weight of metallocene-catalyzed LLDPE (ExxonMobil's Exceed 1018 or Dow's Elite 5401G) and 10% by weight of LDPE (Relen, 1020FA20 ex Reliance Industries Limited, India) in the second polyethylene sealing layer. The m-LLDPE has a density of 0.918 g / cc, MFR 0.9 g / 10 min, and the LDPE has a density of 0.92 g / cc and MFR 2 g / 10 min. iii) The middle layer constituted 50% by weight of the multilayer film. The middle layer was composed of 90% by weight of recycled HDPE (e.g., Banyan Nation Grade BP2120) and 10 wt% rLDPE (RecycleINrLD23E760, INEOS). A comparative multilayer film with a thickness of 30 micrometers (Example Comp D) was prepared, which had the following film structure: (i) The first polyethylene layer constituted 25% by weight of the multilayer film (Example Comp C). The first polyethylene layer included 90% virgin LLDPE (Relene F18010, ex Reliance Industries Limited, India) and 10% virgin LDPE (Relen, 1020FA20 ex 1796856 of 54 Reliance Industries Limited, India) by weight of the first polyethylene layer. ii) A second polyethylene sealing layer that constituted 25% by weight of the comparative multilayer film. The polyethylene sealing layer was composed of 90% by weight of metallocene-catalyzed LLDPE (ExxonMobil's Exceed 1018 or Dow's Elite 5401G) and 10% by weight of virgin LDPE (Relen, 1020FA20 ex Reliance Industries Limited, India). m-LLDPE has a density of 0.918 g / cc, MFR 0.9 g / 10min and LDPE has a density of 0.92 g / cc and MFR 2 g / 10min. iii) The middle layer constituted 50% by weight of the comparative multilayer film. The middle layer was composed of 90% virgin HDPE and 10% virgin LDPE (Relen, 1020FA20 ex Reliance Industries Limited, India). Table 2 Multilayer film with a thickness of 30 micrometers Example 2 (% w / w) Example Comp D (% w / w) First PE layer 25 25 Recycled LLDPE (by weight of first layer) 90 0 Recycled LDPE (by weight of first layer) 10 0 Virgin LLDPE (by weight of first layer) 0 90 Virgin LDPE (by weight of first layer) 0 10 Middle layer 50 50 1796856 of 54 Recycled HDPE (weight of core layer) 90 0 Recycled LDPE (weight of core layer) 10 0 Virgin HDPE (weight of core layer) 0 90 Virgin LDPE (weight of core layer) 0 10 Second sealing PE layer 25 25 Metallocene-catalyzed LLDPE (weight of second layer) 90 90 Virgin LDPE (weight of second layer) 10 10 Multilayer film properties Tensile strength (N / 15 mm) MD 9 6.8 CD 8.2 7.7 Elongation (%) MD 715.1 608.1 CD 539.2 310.6 Young's modulus MD 272.2 231.7 CD 296.4 300.1 The multilayer film according to the present invention (Example 2) having recycled polyethylene in both the first PE layer and the middle layer showed good bubble stability and the mechanical and functional properties were good and comparable to those of a multilayer film made with virgin polyethylene (Example Comp D).

Claims

1. A flexible multilayer film for preparing a container, characterized in that said flexible multilayer film comprises: i) a first polyethylene layer; ii) a second polyethylene sealing layer; iii) a central layer sandwiched between the first polyethylene layer and the second polyethylene sealing layer; wherein the central layer comprises at least 80% by weight of recycled HDPE; wherein the first polyethylene layer comprises between 50% and 100% by weight of recycled LLDPE, recycled LDPE, or mixtures thereof. Thirteen claims follow.