Paper packaging film with multi-layer barrier film

Abstract

The present disclosure relates to a paper packaging film and a method for making the same, wherein the overall composition comprises at least 80% by weight of a paper component and at most 5% by weight of non-compostable material, and the paper packaging film can be easily recycled by repulping while maintaining high performance packaging properties, including improved barrier performance and high speed operation on packaging equipment.

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE The present disclosure relates to a paper packaging film and a method for manufacturing the same. The present disclosure relates to a paper packaging film containing 80% by weight or more of a polyolefin polymer. [Background technology]

[0002] The goal of increasing the recyclability of paper packaging films becomes more difficult when attempting to create packaging films with improved barrier properties. Traditionally, the barrier properties of paper packaging films are improved by creating polymer multilayer films. Multilayer films include multiple layers specific to creating a barrier layer. As performance requirements increase, the number of layers or layer thickness in the multilayer film increases, reducing the percentage of paper content, which works against the recyclability of the structure.

[0003] Often, when high performance is desired from a paper packaging film, a relatively large amount of additional non-paper material is added to the paper packaging film (e.g., a structure with improved barrier properties). To maintain the recyclability of the paper packaging film, the thickness and / or weight of the paper component is increased to achieve the paper content necessary to designate the packaging material as "recyclable." This additional paper thickness / weight can be problematic in that it increases the bulk of the packaging film, potentially causing processing issues on package-forming equipment. In many cases, increased film thickness and stiffness slows line speeds because it becomes more difficult to pull the film through forming collars. Additionally, the increased paper weight can make sealing the packaging film more difficult because it absorbs heat from the sealing bar and / or prevents pressure from being evenly distributed.

[0004] Without disputing the associated advantages of state-of-the-art systems, there is a need for paper packaging films with high barrier properties that are suitable for both recycling and composting. Summary of the Invention

[0005]

[0003] Embodiments of the present disclosure are directed to a flexible paper packaging film that has improved barrier properties and excellent sealing performance while maintaining recyclability in the paper recycling process. The paper packaging film includes a paper component, a barrier layer, a compostable polymer, and contains a minimal amount of non-compostable material (i.e., a minimal amount of non-paper and non-compostable polymeric material). The paper packaging film has the advantage of offering at least two end-of-life options: (1) a paper recycling (repulping) process and / or (2) a composting process.

[0006] In some embodiments, the overall composition of the paper packaging film comprises 80% or more, 85% or more, 90% or more, or 95% or more by weight of the paper component.

[0007] In some embodiments, the paper wrapping film contains 5% or less by weight of non-compostable material.

[0008] In some embodiments, the paper component is 30 g / m 2 ~360g / m 2 The base weight is in the range of

[0009] In some embodiments, the paper packaging film comprises a multilayer barrier film attached to a paper component. In some embodiments, the paper packaging film comprises an adhesive layer that attaches the multilayer barrier film to the paper component. In some embodiments, the multilayer barrier film and adhesive layer have a combined thickness of 10 μm or less. In some embodiments, the combined thickness is in the range of 4 μm to 8 μm.

[0010] In some embodiments, the multilayer barrier film comprises a transfer substrate and a barrier layer deposited thereon by physical vapor deposition (PVD). In some embodiments, the transfer substrate comprises a heat seal layer and, optionally, a lacquer layer.

[0011] In some embodiments, the heat seal layer comprises a non-oriented film. In some embodiments, the heat seal layer comprises a compostable polymer. In some embodiments, the heat seal layer comprises one or more of polylactic acid (PLA), polybutylene adipate terephthalate (PBAT), polybutylene succinate (PBS), polyhydroxyalkanoate (PHA), and / or polyvinyl alcohol (PVOH).

[0012] In some embodiments, the heat seal layer has a thickness in the range of 2 μm to 10 μm, including all values ​​and subranges therebetween. In some embodiments, the heat seal layer has a thickness in the range of 2 μm to 8 μm, or in the range of 2 μm to 6 μm. In some embodiments, the heat seal layer is directly coupled to the barrier layer.

[0013] In some embodiments, the transfer substrate further comprises a lacquer layer. The lacquer layer may be disposed between the barrier layer and the heat seal layer. In some embodiments, the lacquer layer comprises one or more of polyurethane (PU), polyvinyl alcohol (PVOH), and / or ethylene vinyl alcohol (EVOH). In some embodiments, the lacquer layer has a thickness in the range of 1 μm to 2 μm.

[0014] In some embodiments, the barrier layer comprises one or more of a metal, a metal oxide, and / or an inorganic oxide, hi some embodiments, the barrier layer comprises one or more of aluminum (Alu), aluminum oxide (AlOx), and / or silicon oxide (SiOx).

[0015] Another embodiment is directed to a method for producing a paper packaging film. In some embodiments, the method includes coating a base web having a thickness in the range of 6 μm to 50 μm with a multilayer barrier film, attaching the multilayer barrier film to a paper component by a lamination process to form an intermediate structure, and removing the base web from the intermediate structure to obtain the paper packaging film.

[0016] In some embodiments, a single transfer operation includes attaching the multilayer barrier film to the paper component and removing the base web from the intermediate structure, hi some embodiments, the attachment of the multilayer barrier film to the paper component and the removal of the base web from the intermediate structure are performed as separate operations.

[0017] The base film may be oriented (uniaxially or biaxially oriented) or unoriented (i.e., blown or cast without orientation). In some embodiments, the base web comprises one or more of oriented polyethylene (OPE) film, oriented polyethylene terephthalate (OPET) film, oriented polypropylene (OPP) film, and / or oriented polyamide (OPA) film.

[0018] In some embodiments, coating the base web comprises depositing a transfer substrate on the base web and depositing a barrier layer on the transfer substrate by physical vapor deposition (PVD), the combination of the barrier layer and the transfer substrate forming a multilayer barrier film.

[0019] In some embodiments, attaching the multilayer barrier film to the paper component comprises disposing an adhesive layer between the multilayer barrier film and the paper component.

[0020] In another embodiment, a method for producing a paper packaging film includes producing a base web and a heat-seal layer by coextrusion, depositing a barrier layer on the heat-seal layer by physical vapor deposition (PVD), attaching the barrier layer to a paper component by a lamination process to form an intermediate structure, and removing the base web from the intermediate structure to expose the heat-seal layer and obtain a paper packaging film. [Brief explanation of the drawings]

[0021] The present disclosure may be more fully understood in consideration of the following detailed description of various embodiments of the disclosure in connection with the accompanying drawings, in which:

[0022] [Figure 1] FIG. 1 illustrates a process flow diagram of a method for producing a paper packaging film according to one or more embodiments.

[0023] [Figure 2] FIG. 2 illustrates a process flow diagram of a method for producing a paper packaging film according to one or more embodiments.

[0024] [Figure 3] 3, 4 and 5 are schematic cross-sectional views of film structures at intermediate stages in the formation of a paper packaging film. [Figure 4] Same as above. [Figure 5] Same as above.

[0025] [Figure 6] 6 and 7 are schematic cross-sectional views of embodiments of the final paper packaging film. [Figure 7] Same as above.

[0026] The drawings show some, but not all, embodiments. The elements shown in the drawings are illustrative and are not necessarily to scale, and the same (or similar) reference numerals refer to the same (or similar) features throughout the drawings. DETAILED DESCRIPTION OF THE INVENTION

[0027] Provided herein is a paper packaging film that overcomes the shortcomings of previously available films. The paper packaging film of the present disclosure is uniquely designed to achieve a key combination of 1) recyclability (high paper content), 2) ease of packaging conversion, and 3) high barrier performance. Furthermore, this unique combination of layers and materials allows for high overall paper content and low thickness, enabling excellent runnability (i.e., high speeds) on packaging equipment.

[0028] As used herein, the "total composition" of a paper packaging film refers to all materials contained therein. The total composition of a paper packaging film may include 80% by weight or more, 85% by weight or more, 90% by weight or more, or 95% by weight or more of a paper component. The total composition of a paper packaging film may include 99% by weight or less, 98% by weight or less, 97% by weight or less, or 96% by weight or less of a paper component. For example, the total composition of a paper packaging film may include 85% by weight to 98% by weight of a paper component (including all values ​​and subranges therebetween). The total composition of a paper packaging film may include 5% by weight or less, 4% by weight or less, 3% by weight or less, 2% by weight or less, or 1% by weight or less of non-compostable materials. The total composition of a paper packaging film may include compostable materials (e.g., compostable polymers) that are not paper components. The overall composition of the paper packaging film may include 15% by weight or less, 10% by weight or less, 5% by weight or less, 4% by weight or less, 3% by weight or less, 2% by weight or less, or 1% by weight or less of compostable material that is not a paper component. For example, the overall composition of the paper packaging film may include 90% by weight of the paper component, 5% by weight of a compostable polymer, and 5% by weight of non-compostable material. In another example, the overall composition of the paper packaging film may include 80% to 95% by weight of the paper component, 5% to 20% by weight of a compostable polymer, and 5% by weight or less of non-compostable material.

[0029] The paper packaging film described herein comprises a multilayer barrier film attached to a paper component. In some embodiments, the multilayer barrier film is attached entirely to the paper component. As used herein, the term "entirely" means, for example, that 1% or less, or 0.5% or less of the multilayer barrier film is not attached to the paper component. In some embodiments, a portion of the multilayer barrier film is attached to the paper component. As described herein, a portion of the multilayer barrier film attached to the paper component means that the multilayer barrier film remains at least partially attached to the paper component, and that the multilayer barrier film remains undamaged and attached to the paper component during manufacturing / processing. Furthermore, the multilayer barrier film is partially or completely coextensive with the paper component.

[0030] Paper packaging films may include additional layers. These material combinations can be described as multilayer films (e.g., structures or laminates). The term "layer" as used herein refers to a component of a film. In other words, a film is composed of one or more layers. A layer is a structure of a single material type or a homogeneous mixture of materials. A layer may be a single polymer, a mixture of materials within a single polymer type, or a mixture of various polymers. A layer may include a metallic material or have additives. A layer may be continuous with the film, or may be discontinuous or patterned. Both the layer and the film have a relatively small thickness (z-direction) compared to their respective lengths and widths (x- and y-directions).

[0031] As used herein, the term "compostable" refers to materials, e.g., polymers, layers, films, packaging materials, that can decompose and biodegrade under industrial and home composting conditions (12 weeks at 58°C or 26 weeks at 21°C, respectively) and meet industrial composting standards, e.g., EN 13432-2000, ASTM D6400 "Standard Specification for Labeling of Plastics Designed to be Aerobically Composted in Municipal or Industrial Facilities" or ASTM D6868 "Standard Specification for Labeling of End Items that Incorporate Plastics and Polymers as Coatings or Additives with Paper and Other Substrates Designed to be Aerobically Composted in Municipal or Industrial Facilities" and home composting standards, e.g., AS-5810-2010 NF T51800. Compostable polymers include, but are not limited to, polylactic acid (PLA), polybutylene adipate terephthalate (PBAT), and / or polyvinyl alcohol (PVOH).

[0032] As used herein, "PLA polymer" or "PLA" is a polylactic acid-based compostable polymer. Commercially available examples of PLA polymer are available from Total Corbion and NatureWorks. A layer of a film comprising PLA may comprise at least 50% by weight, at least 75% by weight, or at least 95% by weight of PLA polymer.

[0033] As used herein, "PBAT polymer" or "PBAT" refers to a poly(butylene adipate-co-terephthalate)-based compostable biopolymer. Commercially available examples of PBAT biopolymer are available from a number of suppliers, including, but not limited to, Mitsubishi, Novamont, Jiangsu Torise Biomaterials Co., and BASF. A layer of a film comprising PBAT may comprise at least 50% by weight, at least 75% by weight, or at least 95% by weight of PBAT polymer.

[0034] As used herein, the term "non-compostable" refers to materials that are not compostable (i.e., materials that cannot decompose and biodegrade under industrial and home composting conditions (12 weeks at 58°C or 26 weeks at 21°C, respectively). In paper packaging films, examples of layers that may contain non-compostable materials include, but are not limited to, adhesive layers, barrier layers, and / or lacquer layers. Examples of non-compostable materials include, but are not limited to, polyolefins, EVOH, SiOx, vapor-deposited metals, inks, and / or overlacquers.

[0035] All layers and films described herein have two opposing major surfaces defined by the xy plane. As used herein, the term "outer layer" refers to one or more layers of a film that are on either major surface of the film, i.e., a layer that is not between two other layers of the film. A film has an outer surface that will be on the outside of the packaging material in which it is used. When formed into a packaging material, the outer surface of the film will be exposed to the environment. A film has an inner surface that will be on the inside of the packaging material in which it is used. When formed into a packaging material, the inner surface will be used to form a seal and will be exposed to the packaged product.

[0036] One or more of the layers or films of the paper packaging film may be partially or completely coextensive with one another.

[0037] As used herein, the term "adjacent" means that objects, e.g., layers of film, are in close proximity to one another, with or without an intervening object, e.g., an adhesive layer. As used herein, the terms "directly adjacent," "directly connected," or "directly in contact" mean that objects are in contact with one another without an intervening object.

[0038] All layers and films can be produced by any suitable method known to those skilled in the art. Layers and films can be produced by coextrusion, curtain coating, and multi-station lacquering.

[0039] The paper conversion process and the formation of layers / films on paper components present several challenges. Vacuum coating of paper materials is problematic because the moisture content of the paper causes outgassing during the vacuum process. Additionally, fibers released from the paper contaminate the vacuum pump. Packaging papers are typically much thicker than films, typically 40 μm or more, while polymer films are in the 10 μm to 20 μm range. Therefore, PVD coating of paper is very inefficient using a batch vacuum deposition process.

[0040] The surface of the paper component is not ideal for vacuum deposition of a high-quality barrier layer; even the smoothest paper surface is not flat enough for a defect-free PVD coating. Normal suction on the paper will cause the PVD layer to crack. Furthermore, combining a PVD layer on paper is not ideal for flex crack resistance.

[0041] The typical process for applying a PVD barrier layer to a paper component involves applying a primer coating to the paper prior to PVD coating. If the primer coating is water-sensitive, such as EVOH, the coating will be prone to absorbing water through the paper component, causing the paper component to swell and subsequently crack the PVD layer. By placing the PVD layer between the lamination adhesive layer facing the paper component and the EVOH support layer, the support layer is protected by the PVD layer from excessive moisture and swelling, thereby preventing cracking of the PVD layer. PVD coating on primer-coated paper is inefficient and suffers from the same problems as PVD coating on uncoated paper.

[0042] The methods for making paper packaging films described herein advantageously preserve the barrier function of the multilayer barrier film of the paper packaging film and insulate the multilayer barrier film from the adverse effects of the paper converting process.

[0043] 1 illustrates a process flow diagram of a method 100 for manufacturing a paper packaging film according to one or more embodiments. The method 100 includes coating a base web with a multilayer barrier film (operation 102), attaching the multilayer barrier film to a paper component by a lamination process to form an intermediate structure (operation 104), and removing the base web from the intermediate structure to obtain the paper packaging film (operation 106). In some embodiments, a single transfer operation includes attaching the multilayer barrier film to the paper component (operation 104) and removing the base web from the intermediate structure (operation 106).

[0044] In some embodiments, in operation 102, coating the base web includes depositing a transfer substrate on the base web and depositing a barrier layer on the transfer substrate by physical vapor deposition (PVD).

[0045] In some embodiments, attaching the multilayer barrier film to the paper component in operation 104 includes disposing an adhesive layer between the multilayer barrier film and the paper component.

[0046] In some embodiments, the second paper component is attached to the paper packaging film by a second lamination process. In specific embodiments where the paper packaging film has a paper component and a second paper component, the paper component is attached to the top surface of the multilayer barrier film by an adhesive layer. In specific embodiments where the paper packaging film has a paper component and a second paper component, the second paper component is attached to the bottom surface of the multilayer barrier film by placing an adhesive layer between the bottom surface of the multilayer barrier film and the second paper component.

[0047] In specific embodiments, the second paper component may have the same or similar properties as the "paper component" described herein. In specific embodiments, the second lamination process may have the same or similar properties as the "lamination process" described herein, or may require the same process conditions.

[0048] 2 illustrates a process flow diagram of a method 150 for manufacturing a paper packaging film according to one or more embodiments. The method 150 includes producing a base web and a transfer substrate by coextrusion (operation 152), depositing a barrier layer on a heat-seal layer by physical vapor deposition (PVD) (operation 154), attaching the barrier layer to a paper component by a lamination process to form an intermediate structure (operation 156), and removing the base web from the intermediate structure to obtain a paper packaging film having a heat-seal layer thereon (operation 158). Separation occurs between the base web and the heat-seal layer in operation 158. The coextruded transfer substrate comprises the heat-seal layer. The coextruded transfer substrate may also include other layers, such as a lacquer layer.

[0049] In some embodiments, a single transfer operation includes attaching a barrier layer to a paper component by a lamination process to form an intermediate structure (operation 156) and removing the base web from the intermediate structure (operation 158).

[0050] The methods described herein advantageously leave the PVD-deposited barrier layer intact and attached to the heat-seal layer (and ultimately to the paper component) upon removal of the base web from the intermediate structure (operation 158). In specific embodiments, the PVD-deposited barrier layer is advantageously attached to the heat-seal layer (and ultimately to the paper component) upon complete removal of the base web from the intermediate structure (operation 158).

[0051] Advantageously, the methods described herein allow each layer added to the paper component to be very thin. By utilizing PVD barrier layers, when the multilayer barrier film is attached to the paper component by adhesive lamination and removal of the base film, the adhesive, barrier, and heat-seal layers (and lacquer layers, if present) are very thin, thus occupying less material in the overall structure. In this way, the paper packaging film remains recyclable due to its high paper component content, while also benefiting from the high performance barrier and sealing layers.

[0052] Figures 3, 4, and 5 are schematic cross-sectional views of film structures at intermediate stages in forming the paper packaging film shown in Figure 6. Figure 7 is a schematic cross-sectional view of another embodiment of a paper packaging film. The paper packaging films illustrated in Figures 6 and 7 may be formed by method 100 and / or method 150.

[0053] 3 illustrates a transfer substrate 203 on a base web 250. The base web 250 includes one or more of an oriented polyethylene (OPE) film, an oriented polyethylene terephthalate (OPET) film, an oriented polypropylene (OPP) film, and / or an oriented polyamide (OPA) film.

[0054] 3, the transfer substrate 203 comprises a heat seal layer 204 and a lacquer layer 205. In some embodiments, the heat seal layer 204 comprises a non-oriented film. In some embodiments, the heat seal layer 204 comprises a compostable polymer. In some embodiments, the heat seal layer 204 comprises one or more of polylactic acid (PLA), polybutylene adipate terephthalate (PBAT), and / or polyvinyl alcohol (PVOH).

[0055] 4 illustrates the result of operation 156 of method 150 applied to the film of FIG. 3 , depositing a barrier layer 206 on a transfer substrate 203 comprising a heat seal layer 204 and a lacquer layer 205. The transfer substrate 203 and the barrier layer 206 deposited on the transfer substrate 203 form a multilayer barrier film 202. In some embodiments, the heat seal layer 204 is directly connected to the barrier layer 206 such that there is no intervening element / layer / film between the heat seal layer 204 and the barrier layer 206 (i.e., there is no lacquer layer 205).

[0056] 5 illustrates the results of operation 104 of method 100 and operation 156 of method 150, attaching the multilayer barrier film 202 of the structure shown in FIG. 4 to a paper component 210 to form an intermediate structure. In some embodiments, attaching the multilayer barrier film 202 to the paper component 210 in operation 104 includes disposing an adhesive layer 208 between the multilayer barrier film 202 and the paper component 210.

[0057] FIG. 6 illustrates the results of operation 106 of method 100 and operation 158 of method 150, in which base web 250 is removed from the intermediate structure (shown in FIG. 5) to expose heat seal layer 204 and result in paper packaging film 200.

[0058] 7 illustrates a schematic cross-sectional view of a paper packaging film 200′ having a transfer substrate 203. In one or more embodiments, the transfer substrate 203 comprises a single layer. In some embodiments, the transfer substrate 203 comprises a heat seal layer having the same or similar properties as the heat seal layer 204. The embodiment illustrated in FIG. 7 includes a barrier layer 206 deposited by physical vapor deposition (PVD) on the transfer substrate 203, with the transfer substrate 203 and barrier layer 206 defining a multilayer barrier film 202. FIG. 7 also illustrates an adhesive layer 208 between the multilayer barrier film 202 and the paper component 210.

[0059] Each of the layers / films illustrated in Figures 3-7 has a thickness measured in the z-direction. In some embodiments, the heat seal layer 204 has a thickness 204A in the range of 2 μm to 10 μm. In some embodiments, the heat seal layer 204 has a thickness 204A in the range of 2 μm to 8 μm, or in the range of 2 μm to 6 μm. In some embodiments, the lacquer layer 205 has a thickness 205A in the range of 1 μm to 2 μm. In some embodiments, the transfer substrate 203 including the heat seal layer 204 and the lacquer layer 205 has a thickness in the range of 3 μm to 12 μm. In some embodiments, the base web 250 has a thickness 250A in the range of 6 μm to 50 μm.

[0060] In some embodiments, the multilayer barrier film 202 and adhesive layer 208 have a combined thickness of 10 μm or less, hi some embodiments, the combined thickness is in the range of 4 μm to 8 μm.

[0061] Referring again to the paper component, the paper component is the outer layer of the paper packaging film that is disposed on the outer surface of the paper packaging film. In some embodiments, the paper component includes additional components, such as ink or overlacquer, adjacent to or on the outer surface of the paper component. These additional components may cover a portion of the outer surface or the entire outer surface.

[0062] A "paper component" may be any type of paper that can be processed in a paper recycling (repulping) process. As used herein, the term "paper component" may be described in terms of the amount of cellulose fiber in the paper component. For example, the paper component may include cellulose fiber or consist essentially of cellulose fiber. As used in this context, "consisting essentially of" means that the overall composition of the paper component comprises 95% or more, 98% or more, 99% or more, 99.9% or more, or 100% cellulose fiber. In some cases, the paper component may contain up to 20% by weight of mineral filler, and correspondingly, an amount of cellulose fiber of 80% by weight or more.

[0063] Thus, in embodiments where the overall composition of the paper packaging film comprises 80% by weight or more, 85% by weight or more, 90% by weight or more, or 95% by weight or more of a paper component, the overall composition of the paper packaging film comprises 80% by weight or more, 85% by weight or more, 90% by weight or more, or 95% by weight or more of cellulose fibers.

[0064] In some embodiments, the basis weight of the paper component is 30 g / m 2 ~360g / m 2 30 g / m 2 ~100g / m 2 or 30 g / m 2 ~70g / m 2This includes within the range of 1000 to 15000 gsm. Because additional components are minimized, the weight of the paper component can be reduced while maintaining easy recyclability. Examples of paper components useful in paper packaging films include, but are not limited to, kraft paper, parchment paper, and bleached paper. The paper component may be coated (i.e., clay-coated) or uncoated. Examples of papers commonly used in packaging that would be acceptable for the paper packaging films described herein include machine-glazed bleached kraft paper (MGBK), single-sided clay-coated paper (C1S), and double-sided clay-coated paper (C2S). However, less common papers with improved mechanical or barrier properties through the use of specialty fibers or additives may also be part of the paper packaging films described herein. Clay-coated paper can contain up to 15 gsm of coating, resulting in a significant proportion of latex being applied. This generally means that clay-coated paper is not considered compostable unless the latex used is a compostable polymer. In embodiments in which the paper component is coated, the overall composition of the paper component has 95% or more, 98% or more, 99% or more, 99.9% or more, or 100% cellulose fibers.

[0065] As used herein, the term "basis weight" refers to the amount of material by weight present in a given area of ​​a film or layer. Typically, the defined area is in square meters, although any area can be used. The area is defined by the length-width (i.e., x- and y-directions) of the film or layer. A material with a given thickness (z-direction) and density will have a specific weight when covering a defined area (i.e., square meters). Basis weight is a commonly used measure of paper weight because paper density can vary widely. In other words, measuring paper thickness in the z-direction can be difficult. Materials applied in discontinuous layers, such as patterned materials, can be defined by basis weight. In the case of patterns, basis weight refers to the amount of material by weight present when covering a defined area. In the film converting industry, basis weight is commonly used to measure the weight of materials, such as paper and patterned materials.

[0066] In some embodiments, the paper packaging film comprises a multi-layer barrier film attached to a paper component, hi some embodiments, the paper packaging film comprises an adhesive layer that attaches the multi-layer barrier film to the paper component.

[0067] In some embodiments, the multilayer barrier film comprises a transfer substrate and a barrier layer deposited thereon by physical vapor deposition (PVD). In some embodiments, the transfer substrate comprises a heat seal layer and, optionally, a lacquer layer.

[0068] In some embodiments, the transfer substrate further comprises a lacquer layer, hi some embodiments, the lacquer layer comprises one or more of polyurethane (PU), polyvinyl alcohol (PVOH), and / or ethylene vinyl alcohol (EVOH).

[0069] In some embodiments, the barrier layer comprises one or more of a metal, a metal oxide, and / or an inorganic oxide. In some embodiments, the barrier layer comprises one or more of aluminum oxide (AlOx) and / or silicon oxide (SiOx). The barrier layer can reduce the permeation of oxygen, moisture, or both oxygen and moisture.

[0070] The barrier material may be multi-layered and may include different layers of barrier material. The barrier material may also be a mixture of multiple barrier materials.

[0071] In some embodiments, the paper packaging film comprising the multilayer barrier film described herein has an average oxygen transmission rate (OTR) of 5 cm, measured according to ASTM F1927 using conditions of 1 atmosphere, 23°C, and 50% RH. 3 / m 2 / day or less, 1cm 3 / m 2 / day or less, or 0.5 cm 3 / m 2 In some embodiments, a paper packaging film comprising a barrier material coated on a polymeric film has a mean water vapor transmission rate (MVTR) value (sometimes referred to as water vapor transmission rate (WVTR)) of 1 g / m or less, measured according to ASTM F1249 using conditions of 1 atmosphere, 38°C, and 90% RH. 2 / day or less.

[0072] The paper packaging film may include an adhesive layer that bonds the paper component to the barrier material. The adhesive layer may be in direct contact with the paper component. The adhesive layer may be in direct contact with the multilayer barrier film. The adhesive layer may be applied by any known means of web-to-web lamination, such as dry bond lamination, wet bond lamination, or heat lamination. The adhesive layer may have a thickness of 0.5 g / m 2 ~4.0g / m 2 The dry basis weight (i.e., after solvent removal) may be between 100 and 1500 gram.

[0073]

[0010] Advantageously, embodiments of the present disclosure provide a paper packaging film that includes a water-sensitive adhesive layer. As used herein, the term "water-sensitive" means that the adhesive layer loses its adhesive and / or cohesive properties upon prolonged exposure to or immersion in liquid water, thereby allowing the paper component to peel (separate) from the remainder of the paper packaging film structure during the repulping process. Examples of materials that can be used for the adhesive layer between the paper component and the multilayer barrier film include, but are not limited to, latex / casein mixtures, starch, sugar derivatives, cellulose, amino resins, (poly)acrylates, polyvinyl alcohol (PVOH), polyvinyl acetate, polyacrylic acid, maleic acid-modified ethylene copolymers, methylcellulose, carboxymethylcellulose, carboxy-functional polyesters, polyethylene succinate, polybutylene succinate, ionomers, or hydrophilic polyurethanes.

[0074] As noted above, the paper packaging film may also include ink disposed on the outer surface of the paper packaging film, and the type and amount of ink may vary within the scope of local paper recycling guidelines.

[0075] Paper packaging films can be advantageously used to form packaging. The term "packaging" is used herein to refer to an article capable of containing an object (i.e., a product), formed by joining one or more paper packaging films or other packaging components together or around themselves to form an interior space of the packaging. A "packaged product" refers to one or more packaging components that form a hermetically sealed packaging and the product therein. As used herein, hermeticity refers to a seal or sealed packaging that is completely closed and essentially airtight. Hermetically sealed packaging is typically stored for periods exceeding several days, and the integrity of the packaging must be maintained. Packaging integrity includes consistent appearance, maintaining barrier properties, maintaining laminated bonds, and maintaining a seal.

[0076] The product may be any type of food, beverage, pharmaceutical or other medical aid, dietary supplement, consumer product, or industrial product. The product may be fluid in nature. Examples of products include, but are not limited to, condiments such as ketchup, mustard, mayonnaise, or condiments, pudding, yogurt, cheese sauce, nut butter, jam / jelly, dairy or non-dairy creamer, guacamole, applesauce, pureed baby food, infant formula, nutritional drinks / shakes, beverage or supplement concentrates, cough syrup, fish oil, lotions, salves / ointments, personal care products, soaps / detergents, or solvents.

[0077] As noted above, the product may be fluid in nature or may have a fluid component. The product may be aqueous (i.e., contain water as a medium or primary component) or oil-based (i.e., contain oil as a medium or primary component). The paper packaging films described herein may be particularly useful for containing acidic products for long shelf lives (days, weeks, or months) while minimizing barrier loss. The product may have a pH of less than 7, less than 6, less than 5, less than 4, or less than 3.

[0078] The packaged products disclosed herein include a package formed from at least one paper package film and optionally other components. In some embodiments of the packaged products, the entire package is formed from a single paper package film that is folded and sealed to itself (i.e., a flow wrap or stick pack configuration).

[0079] For each packaged product, a first side of the paper packaging film faces away from the product and is exposed to the external environment, and a second side of the compostable multilayer film faces the product and is exposed to the product and the internal environment. The paper component may be on or near the first side facing away from the packaged product. The second side may include a heat seal layer.

[0080] The paper packaging films disclosed herein are particularly useful for packaged products in small sizes, e.g., 6" x 9", 5" x 7", 5" x 5", 3" x 3", and 3" x 2", because these types of packaging are difficult to collect and / or separate for recycling. Small packaging and small packaging components may be suitable for compostable end-of-life solutions rather than recycling.

[0081] The paper packaging films disclosed herein are particularly useful for packaged product forms and / or product types that leave significant product residue in the packaging after consumer use. The packaged product may be shaped or configured to prevent / prohibit complete removal of the product. The packaged product may be shaped or configured to prevent / prohibit cleaning of the packaging after use. The packaged product may have a tendency to stick or adhere to the packaging. In such cases, the packaging should not be recycled because the product residue would contaminate the recycling process. In such cases, composting is a good solution because the product residue may accelerate the decomposition process.

[0082] In some embodiments of the packaged product, a paper packaging film is sealed to another paper packaging film (i.e., a sachet configuration). In some embodiments of the packaged product, the paper packaging film is a lid component that is sealed to a formed container, e.g., a cup or tray. Packaging that includes components that do not conform to the paper packaging films disclosed herein may also be compostable, such that the entire package is compostable. In some embodiments, packaging includes components that are not compostable, but can be separated from the compostable portion for proper disposal.

[0083] The heat-seal layer of the paper packaging film may have a composition that allows for the formation of a hermetically sealed packaging. In some embodiments, the heat-seal layer comprises a non-oriented film (i.e., the heat-seal layer is part of a non-oriented film). In some embodiments, the heat-seal layer comprises a compostable polymer. In some embodiments, the heat-seal layer comprises one or more of polylactic acid (PLA), polybutylene adipate terephthalate (PBAT), and / or polyvinyl alcohol (PVOH).

[0084] A heat-sealable layer allows two or more surfaces to be joined by the application of both heat and pressure. Heat sealing is a well-known and commonly used process for creating packaging materials and is familiar to those skilled in the art. Without being bound by theory, during heat sealing, the heat-sealable layer softens upon application of heat, allowing the formation of a heat-seal bond. Raising the temperature of the sealable material requires heat to be transferred throughout the paper packaging film, and because the paper component often absorbs much of the heat, it is advantageous for the heat-sealable material to soften and seal at a relatively low temperature. A lower seal initiation temperature (SIT) allows for faster packaging line speeds. For example, some embodiments of paper packaging films may include heat-sealable materials that exhibit an SIT of 110°C or less, 100°C or less, or 90°C or less. Possible heat-sealable materials include, but are not limited to, acrylic copolymers, PET, PE, PP, or hot melts (wax-based).

[0085] The heat seal layer is applied at a thickness that allows for a hermetic seal. In some embodiments, the heat seal layer has a thickness of 1 g / m 2 or more than 3g / m 2 In other embodiments, the heat seal layer may be applied at a basis weight of 8 g / m or more. 2 Below, 9g / m 2 or less than 10g / m 2 For example, the heat seal layer may be coated at a basis weight of about 1 g / m2 ~about 10g / m 2 in the range of 0.01g / m², or approximately 3g / m². 2 ~approx. 9g / m 2 may be in the range of

[0086] The present disclosure will now be illustrated with reference to the following examples. [Example]

[0087] Example

[0088] Example 1 is a theoretical experimental example based on the above-mentioned paper packaging film. 2 The multilayer barrier film can be manufactured by laminating a paper component of 1.3 g / m to a multilayer barrier film. 2 The PVOH-based barrier lacquer layer can be produced by applying a PVOH-based barrier lacquer layer of 50 mg / m2 to a 12 μm polyester film. The lacquer may be applied so as to have low adhesion to the polyester film, for example by not including an adhesion promoter in the lacquer layer. After lacquering, the PVOH-based barrier lacquer layer is coated with 50 mg / m2 of PVOH-based barrier lacquer. 2 The SiOx coating layer can be coated with SiOx of 3 g / m 2 The 12 μm polyester film may then be removed to form an intermediate structure of 67 g / m 2 / / Adhesive 3g / m 2 / / SiOx coating 0.05g / m 2 / / PVOH coating 1.3g / m 2 A paper packaging film having the following structure is obtained: The paper packaging film of Example 1 has an overall composition containing about 94% by weight of paper components and about 4% by weight of non-compostable materials.

[0089] The paper packaging film of Example 1 was made of 1.5 g / m 2The heat seal layer can be added in a pattern such that the level of non-compostable material is minimized and kept below 5%.

[0090] Example 2 is a theoretical experimental example based on the above paper packaging film. Example 2 can be manufactured by first co-extruding a 20 μm polyethylene / 6 μm amorphous PLA / 4 μm PVOH multilayer film. In the second step, the PE / aPLA / PVOH film is coated with 50 mg / m PVOH on the surface. 2 Finally, the SiOx-coated surface of the film is laminated to paper (67 gsm) with a suitable adhesive and the PE layer is removed. The final structure of the paper packaging film is 2 / / Adhesive 3g / m 2 / / SiOx coating 0.05g / m 2 / / PVOH coating 3.0g / m 2 / / / Amorphous PLA heat seal layer 7.5g / m 2 The paper packaging film of Example 2 has an overall composition of about 83% by weight paper components and about 4% by weight non-compostable material.

[0091] Example 3 is a theoretical experimental example based on the above paper packaging film. Example 3 can be manufactured by first co-extruding a 25 μm polyethylene / 8 μm amorphous PLA multilayer film. In the second step, the PE / aPLA film is coated with 50 mg / m2 of polyethylene on the aPLA surface. 2 Finally, the SiOx-coated surface of the film is laminated to paper (67 gsm) with a suitable adhesive and the PE layer is removed. The final structure of the paper packaging film is 2 / / Adhesive 3g / m 2 / / SiOx coating 0.05g / m 2 / / Amorphous PLA heat seal layer 10.0g / m 2The paper packaging film of Example 3 has an overall composition of about 84% by weight paper components and about 4% by weight non-compostable material.

[0092] Examples 4, 5, and 6 are paper packaging films manufactured by the process disclosed herein. The films were manufactured by co-extrusion of a base web and a heat-seal layer (i.e., transfer substrate), depositing a PVD layer of aluminum (of negligible weight) as a barrier layer on the heat-seal layer, laminating it to a paper component, and removing the base web. The structures of the manufactured films are shown in Table 1. [Table 1]

[0093] Embodiments:

[0094] Embodiment 1: A paper packaging film comprising a paper component attached to a multilayer barrier film comprising a compostable polymer, the overall composition of the paper packaging film comprising 80% by weight or more of the paper component and 5% by weight or less of non-compostable material.

[0095] Embodiment 2: The paper component is 30 g / m 2 ~360g / m 2 2. The paper packaging film of embodiment 1, having a basis weight in the range of

[0096] Embodiment 3: 3. The paper packaging film according to any one of embodiments 1 to 2, further comprising an adhesive layer that attaches the multilayer barrier film to the paper component.

[0097] Embodiment 4: 4. The paper packaging film according to any one of embodiments 1 to 3, wherein the multilayer barrier film comprises a transfer substrate and a barrier layer deposited thereon by physical vapor deposition (PVD).

[0098] Embodiment 5: 5. The paper packaging film according to any one of embodiments 1 to 4, wherein the transfer substrate comprises a heat seal layer.

[0099] Embodiment 6: 6. The paper packaging film according to any one of embodiments 1 to 5, wherein the heat seal layer comprises a non-stretched film.

[0100] Embodiment 7: 7. The paper packaging film according to any one of embodiments 1 to 6, wherein the heat seal layer comprises a compostable polymer.

[0101] Embodiment 8: 8. The paper packaging film according to any one of embodiments 1 to 7, wherein the compostable polymer is selected from the group consisting of polylactic acid (PLA), polybutylene adipate terephthalate (PBAT), polybutylene succinate (PBS), and polyhydroxyalkanoate (PHA).

[0102] Embodiment 9: 9. The paper packaging film according to any one of embodiments 5 to 8, wherein the heat seal layer has a thickness in the range of 2 μm to 10 μm.

[0103] Embodiment 10: 10. The paper packaging film according to any one of embodiments 5 to 9, wherein the heat seal layer is directly connected to the barrier layer.

[0104] Embodiment 11: 11. The paper packaging film of any one of claims 5 to 10, wherein the transfer substrate further comprises a lacquer layer, the lacquer layer comprising one or more of polyurethane (PU), polyvinyl alcohol (PVOH), and / or ethylene vinyl alcohol (EVOH).

[0105] Embodiment 12: 12. The paper packaging film according to embodiment 11, wherein the lacquer layer has a thickness in the range of 1 μm to 2 μm.

[0106] Embodiment 13: 13. The paper packaging film according to any one of embodiments 4 to 12, wherein the barrier layer comprises one or more of a metal, a metal oxide, and / or an inorganic oxide.

[0107] Embodiment 14: 14. The paper packaging film of embodiment 13, wherein the barrier layer comprises one or more of aluminum oxide (AlOx) and / or silicon oxide (SiOx).

[0108] Embodiment 15: 15. The paper packaging film according to any one of embodiments 5 to 14, wherein the combined thickness of the multilayer barrier film and the adhesive layer is 10 μm or less.

[0109] Embodiment 16: 16. The paper packaging film according to embodiment 15, having a combined thickness in the range of 4 μm to 8 μm.

[0110] Embodiment 17: 17. The paper packaging film of any one of embodiments 1 to 16, wherein the overall composition of the paper packaging film comprises 85% or more by weight of a paper component and 5% or less by weight of non-compostable material.

[0111] Embodiment 18: 1. A method for producing a paper packaging film, the method comprising: coating a base web having a thickness in the range of 6 μm to 50 μm with a multilayer barrier film comprising a compostable polymer; attaching the multilayer barrier film to a paper component by a lamination process to form an intermediate structure; and removing the base web from the intermediate structure to obtain a paper packaging film, wherein the overall composition of the paper packaging film comprises 80% or more by weight of the paper component and 5% or less by weight of non-compostable material.

[0112] Embodiment 19: 20. The method of embodiment 18, wherein a single transfer operation comprises attaching the multilayer barrier film to the paper component and removing the base web from the intermediate structure.

[0113] Embodiment 20: 20. The method of any one of claims 18 and 19, wherein the base web comprises one or more of an oriented polyethylene (OPE) film, an oriented polyethylene terephthalate (OPET) film, an oriented polypropylene (OPP) film, and / or an oriented polyamide (OPA) film.

[0114] Embodiment 21: 21. The method of any one of claims 18-20, wherein coating the base web comprises depositing a transfer substrate on the base web and depositing a barrier layer on the transfer substrate by physical vapor deposition (PVD), the combination of the barrier layer and the transfer substrate forming a multilayer barrier film.

[0115] Embodiment 22: 22. The method of any one of embodiments 18-21, wherein attaching the multilayer barrier film to the paper component comprises disposing an adhesive layer between the multilayer barrier film and the paper component.

[0116] Embodiment 23: 22. The method of embodiment 21, wherein the transfer substrate comprises a heat seal layer and, optionally, a lacquer layer.

[0117] Embodiment 24: 24. The method of embodiment 23, wherein the heat seal layer comprises a non-oriented film.

[0118] Embodiment 25: 25. The method of any one of embodiments 23-24, wherein the heat seal layer comprises a compostable polymer.

[0119] Embodiment 26: 26. The method of any one of claims 23-25, wherein the heat seal layer comprises one or more of polylactic acid (PLA), polybutylene adipate terephthalate (PBAT), polybutylene succinate (PBS), polyhydroxyalkanoate (PHA), polyethylene vinyl alcohol (EVOH), and / or polyvinyl alcohol (PVOH).

[0120] Embodiment 27: 27. The method of any one of embodiments 23 to 26, wherein the heat seal layer has a thickness in the range of 2 μm to 10 μm.

[0121] Embodiment 28: 28. The method of any one of embodiments 23 to 27, wherein the heat seal layer is directly connected to the barrier layer.

[0122] Embodiment 29: 24. The method of embodiment 23, wherein the transfer substrate further comprises a lacquer layer, the lacquer layer comprising one or more of polyurethane (PU), polyvinyl alcohol (PVOH), and / or ethylene vinyl alcohol (EVOH).

[0123] Embodiment 30: 30. The method of any one of embodiments 21-29, wherein the barrier layer comprises one or more of aluminum oxide (AlOx) and / or silicon oxide (SiOx).

[0124] Embodiment 31: 31. The method of any one of embodiments 18-30, wherein the overall composition of the paper packaging film comprises 85% or more by weight of a paper component and 5% or less by weight of non-compostable material.

[0125] Embodiment 32: 1. A method for producing a paper packaging film, the method comprising: producing a base web and a heat-seal layer by coextrusion; depositing a barrier layer on the heat-seal layer by physical vapor deposition (PVD); attaching the barrier layer to a paper component by a lamination process to form an intermediate structure; and removing the base web from the intermediate structure to expose the heat-seal layer and obtain a paper packaging film, wherein the overall composition of the paper packaging film comprises 80% or more by weight of the paper component.

[0126] Embodiment 33: 1. A paper packaging film comprising: a multilayer barrier film including a transfer substrate and a barrier layer deposited by physical vapor deposition (PVD); and an adhesive layer attaching a paper component to the multilayer barrier film, wherein the transfer substrate comprises a heat seal layer, the heat seal layer having a thickness in the range of 2 μm to 8 μm, the barrier layer comprising one or more of metal, aluminum oxide (AlOx) and / or silicon oxide (SiOx), and the overall composition of the paper packaging film comprises 85% or more by weight of the paper component.

[0127] Embodiment 34: 34. The paper packaging film of embodiment 33, wherein the heat seal layer comprises a compostable polymer.

[0128] Embodiment 35: 35. The paper packaging film according to any one of embodiments 33 to 34, wherein the heat seal layer comprises a non-stretched film.

[0129] Embodiment 36: 36. The paper packaging film of any one of claims 33 to 35, wherein the heat seal layer comprises one or more of polylactic acid (PLA), polybutylene adipate terephthalate (PBAT), and / or polyvinyl alcohol (PVOH).

Claims

1. A paper packaging film, a paper component attached to a multilayer barrier film comprising a compostable polymer; A paper packaging film, the overall composition of which comprises 80% by weight or more of the paper component and 5% by weight or less of non-compostable material.

2. The paper component has a thickness of 30 g / m 2 ~360g / m 2 2. The paper packaging film of claim 1, having a basis weight within the range of:

3. The paper packaging film of claim 1 further comprising an adhesive layer attaching the multilayer barrier film to the paper component.

4. 10. The paper packaging film of claim 1, wherein the multilayer barrier film comprises a transfer substrate and a barrier layer deposited thereon by physical vapor deposition (PVD).

5. The paper packaging film of claim 4 , wherein the transfer substrate comprises a heat seal layer.

6. The paper packaging film according to claim 5 , wherein the heat seal layer comprises a non-oriented film.

7. The paper packaging film according to claim 5 , wherein the heat seal layer comprises the compostable polymer.

8. 2. The paper packaging film of claim 1, wherein the compostable polymer is selected from the group consisting of polylactic acid (PLA), polybutylene adipate terephthalate (PBAT), polybutylene succinate (PBS), and polyhydroxyalkanoate (PHA).

9. 6. The paper packaging film according to claim 5, wherein the heat seal layer has a thickness in the range of 2 μm to 10 μm.

10. The paper packaging film of claim 5 , wherein the heat seal layer is directly connected to the barrier layer.

11. 6. The paper packaging film of claim 5, wherein the transfer substrate further comprises a lacquer layer disposed between the heat seal layer and the barrier layer, the lacquer layer comprising one or more of polyurethane (PU), polyvinyl alcohol (PVOH), and / or ethylene vinyl alcohol (EVOH).

12. 12. The paper packaging film according to claim 11, wherein the lacquer layer has a thickness in the range of 1 μm to 2 μm.

13. The paper packaging film of claim 4 , wherein the barrier layer comprises one or more of a metal, a metal oxide, and / or an inorganic oxide.

14. 14. The paper packaging film of claim 13, wherein the barrier layer comprises one or more of aluminum oxide (AlOx) and / or silicon oxide (SiOx).

15. 6. The paper packaging film according to claim 5, wherein the multilayer barrier film and the adhesive layer have a combined thickness of 10 μm or less.

16. 16. The paper packaging film of claim 15, wherein the combined thickness is in the range of 4 μm to 8 μm.

17. 2. The paper packaging film of claim 1, wherein the overall composition of the paper packaging film comprises 85% or more by weight of the paper component and 5% or less by weight of the non-compostable material.

18. 1. A method for producing a paper packaging film, the method comprising: coating a base web having a thickness in the range of 6 μm to 50 μm with a multi-layer barrier film comprising a compostable polymer; attaching said multilayer barrier film to a paper component by a lamination process to form an intermediate structure; removing the base web from the intermediate structure to obtain the paper packaging film; The method, wherein the overall composition of the paper packaging film comprises 80% or more by weight of the paper component and 5% or less by weight of non-compostable material.

19. 20. The method of claim 18, wherein a single transfer operation comprises the attaching of the multilayer barrier film to the paper component and the removing of the base web from the intermediate structure.

20. 20. The method of claim 18, wherein the base web comprises one or more of an oriented polyethylene (OPE) film, an oriented polyethylene terephthalate (OPET) film, an oriented polypropylene (OPP) film, and / or an oriented polyamide (OPA) film.

21. 20. The method of claim 18, wherein the coating of the base web comprises depositing a transfer substrate on the base web and depositing a barrier layer on the transfer substrate by physical vapor deposition (PVD), the combination of the barrier layer and the transfer substrate forming the multilayer barrier film.

22. 20. The method of claim 18, wherein said attaching said multilayer barrier film to said paper component comprises disposing an adhesive layer between said multilayer barrier film and said paper component.

23. 22. The method of claim 21, wherein the transfer substrate comprises a heat seal layer and, optionally, a lacquer layer.

24. The method of claim 23, wherein the heat seal layer comprises a non-oriented film.

25. 24. The method of claim 23, wherein the heat seal layer comprises a compostable polymer.

26. 26. The method of claim 25, wherein the heat seal layer comprises one or more of polylactic acid (PLA), polybutylene adipate terephthalate (PBAT), polybutylene succinate (PBS), polyhydroxyalkanoate (PHA), polyethylene vinyl alcohol (EVOH), and / or polyvinyl alcohol (PVOH).

27. 24. The method of claim 23, wherein the heat seal layer has a thickness in the range of 2 μm to 10 μm.

28. 24. The method of claim 23, wherein the heat seal layer is directly connected to the barrier layer.

29. 24. The method of claim 23, wherein the transfer substrate further comprises the lacquer layer, the lacquer layer comprising one or more of polyurethane (PU), polyvinyl alcohol (PVOH), and / or ethylene vinyl alcohol (EVOH).

30. 22. The method of claim 21, wherein the barrier layer comprises one or more of aluminum oxide (AlOx) and / or silicon oxide (SiOx).

31. 20. The method of claim 18, wherein the overall composition of the paper packaging film comprises 85% or more by weight of the paper component.

32. 1. A method for producing a paper packaging film, the method comprising: Producing by coextrusion a base web and a heat-seal layer comprising a compostable polymer; depositing a barrier layer on the heat seal layer by physical vapor deposition (PVD); attaching said barrier layer to a paper component by a lamination process to form an intermediate structure; removing the base web from the intermediate structure to expose the heat seal layer and obtain the paper packaging film; The method wherein the overall composition of the paper packaging film comprises 80% or more by weight of the paper component.

33. A paper packaging film, a multilayer barrier film comprising a transfer substrate and a barrier layer deposited by physical vapor deposition (PVD); an adhesive layer attaching a paper component to the multilayer barrier film; The transfer substrate comprises a heat seal layer, and the heat seal layer has a thickness in the range of 2 μm to 8 μm; the barrier layer comprises one or more of a metal, aluminum oxide (AlOx) and / or silicon oxide (SiOx); A paper packaging film, wherein the overall composition of the paper packaging film comprises 85% by weight or more of the paper component.

34. 34. The paper packaging film of claim 33, wherein the heat seal layer comprises a compostable polymer.

35. 34. The paper packaging film of claim 33, wherein the heat seal layer comprises a non-oriented film.

36. 34. The paper packaging film of claim 33, wherein the heat seal layer comprises one or more of polylactic acid (PLA), polybutylene adipate terephthalate (PBAT), polybutylene succinate (PBS), polyhydroxyalkanoate (PHA), and / or polyvinyl alcohol (PVOH).

37. 34. The paper packaging film of claim 33, wherein the multilayer barrier film and the adhesive layer have a combined thickness in the range of 4 μm to 10 μm.

Images