Marine biodegradable and recyclable paper-based packaging material with high moisture and oxygen barrier properties

Abstract

The present invention relates to a marine biodegradable and recyclable metallized paper-based multi-layer packaging material that includes a layered arrangement of organic and inorganic materials superimposed to provide a barrier to oxygen and moisture, the organic and inorganic layers being made from materials selected for their marine biodegradability. In one embodiment of the present invention, the metallized paper-based multi-layer packaging material can be recycled along with other paper packaging materials.

Description

Detailed Description of the Invention

[0001] [Technical field] The present invention relates to a marine biodegradable paper-based multi-layer packaging material that includes a paper layer and an ultra-thin metal or metalloid layer for water vapor barrier sandwiched between thin layers of marine biodegradable polymer that provide oxygen barrier and hermeticity to the structure. The resulting packaging material provides excellent moisture and oxygen barrier properties to packaged products while being marine biodegradable and recyclable in the paper recycling stream.

[0002] [Background technology] Plastic packaging is often used in economic activities and people's daily lives. Plastic packaging has several advantages, such as flexibility and light weight. Lightweighting can, for example, save fuel during transportation and reduce CO 2 The barrier properties of plastic packaging help reduce food waste by having a positive effect on extending shelf life. Barrier properties also help ensure food safety.

[0003] However, due to increasing environmental awareness and to ensure a reduction in waste plastic, multi-layer packaging materials have been developed that comprise a paper layer and one or more plastic or metal film layers to provide robustness and barrier properties, particularly to oxygen and moisture.

[0004] Recently, there has been an increased environmental awareness, especially with regard to waste materials, such as used packaging, that are not recycled or properly treated and pollute the oceans. This problem is considered very serious by the industry, which is devoting a lot of effort to develop new packaging materials that are quickly and easily biodegradable when accidentally introduced into the natural, and especially the marine, environment.

[0005] Currently, when producing multi-layer packaging structures, when layers of plastic are applied by known techniques, in particular by extrusion (extrusion lamination) or also by adhesive lamination processes, the thickness of the plastic film obtained on the paper is necessarily high.

[0006] Even when the extruded polymer thickness of such multi-layer structures is relatively low, the cohesive strength of the polymer film is very high, as is the level of adhesion of the polymer to the paper or cardboard (i.e., cellulosic) substrate, which prevents the polymer from being removed from the substrate during recycling and prevents recycling and repulping of the cellulose fiber portion in the paper stream recycling process.

[0007] Thus, multi-layer structures comprising a combination of paper and extruded or adhesively laminated (by standard techniques such as extrusion lamination or extrusion coating) plastic (polymer) films cannot be recycled in a paper stream recycling process because the plastic layers are too thick to be dispersed during the subsequent recycling process and have too high a cohesive strength and adhesion level to be separated from other adjacent material layers in the structure, especially from the paper fibers. The extruded plastic film remains intact in the paper pulp tank, thus making it difficult to recycle the paper pulp through a repulping process.

[0008] Furthermore, the recycling processes of the known laminated materials mentioned above are costly, energy consuming, and characterized by a relatively low yield of recycled paper fibers (about 60% of the total amount of packaging material in the entire structure), and therefore are not environmentally friendly enough in terms of disposal and recycling. There is also room to improve the recyclability of the remaining parts of the packaging material (i.e. the plastic polymer parts and the metal parts, e.g. the aluminum parts) in the paper recycling system.

[0009] Furthermore, in packaging for food products, good barrier properties are essential to maintain the safety and quality of the packaged food, typically including gas barrier (e.g. against oxygen and water vapor (moisture)) and possibly also liquid-tightness.

[0010] One way to provide a good moisture barrier to paper-based packaging materials is the introduction of a metal or metalloid layer into a so-called "metallized" layer. As used herein, the term "metallization" (e.g., in the expression "metallized barrier paper layer") is meant to encompass the deposition of metal or metalloid atoms on the surface of the paper or paperboard. One can even envisage embodiments that include the deposition of alloys of metals and metalloids. Metalloids are close in some of their properties to metals. Aluminum oxide and silicon oxide are examples of metalloids.

[0011] As mentioned above, the current trend is to move from plastics to paper-based packaging materials. However, paper itself is very sensitive to moisture and offers little protection to products packaged in packages made from paper. Furthermore, for economic reasons, it is preferable that paper materials can be handled on the same production lines as traditional multi-layer or single-layer plastics. This avoids new investments in manufacturing machinery, which can negatively impact the cost of the packages produced. However, paper itself is very difficult to process, since it has low resilience. Since paper is hygroscopic and does not provide an adequate barrier against oxygen and moisture, additional materials must be added to achieve a final structure that meets the necessary properties (mechanical strength, resilience, sealing and barrier properties) required for packaging, especially food packaging.

[0012] To provide the required resilience and barrier properties, paper is usually coated with various polymer layers (dispersion coated, extrusion coated, rotogravure, etc.) Additionally, the moisture barrier can be greatly improved by adding a metallized layer within the construction.

[0013] Most of the paper-containing multi-layer structures currently being studied for packaging purposes contain oily organic materials that are not biodegradable. Moreover, if the multi-layer structure is not well designed, the metallized layer will be damaged during conversion into the final packaging, and the high barrier properties of the flat multi-layer structure will be lost after the structure is formed, filled and processed into a sealed package, which is of course undesirable.

[0014] Furthermore, to be accepted into the paper recycling stream process, packaging must contain at least 80-95% paper (depending on local regulations) by its overall structure. However, despite ongoing efforts by the industry to innovate and develop environmentally friendly paper-based packaging, many countries around the world still lack the appropriate infrastructure and recycling facilities to recycle post-consumer paper-based packaging.

[0015] Furthermore, despite increased public relations and awareness campaigns to educate consumers and local governments, a certain percentage of packaging still pollutes rivers and oceans, which is a major concern.

[0016] In view of the above, there is a need for a bio-based multi-layer packaging structure that is fully biodegradable under marine conditions. Further, there is a need for a packaging structure that is characterized by all of the following key features: High barrier properties against oxygen and water vapor (moisture), High resilience to mechanical stress, so that it maintains the same level of barrier even when subjected to deformation processes, such as those used to manufacture the packages; a plastic polymer content that is significantly reduced compared to the content of cellulosic materials; Interlayer adhesion to provide high mechanical resistance (especially stiffness) to structures and packaging made therefrom.

[0017] [Summary of the Invention] The object of the present invention is to provide a marine biodegradable metallized paper-based multi-layer packaging material, which comprises, in order from the outside to the inside, 30~120g / m 2 A paper layer having a basis weight falling within the range At least one first organic layer comprising at least one polymer that is marine biodegradable according to the ISO 22403:2020 standard or its equivalent ASTM D6691:2017 standard, the at least one polymer being selected from the list of polyhydroxyalkanoates (PHAs), microfibrillated or nanofibrillated cellulose, polyglycolides (PGAs), or combinations thereof, the at least one polymer having a density of 0.5 to 15 g / m 2 Preferably, the amount is 1 to 7 g / m 2 a first organic layer, which is applied as a layer in an amount of 0.1 to 0.5 wt %, and said biodegradable polymer has a melting temperature comprised between 160° C. and 200° C., preferably between 170° C. and 180° C.; a vacuum-deposited or transferred metallized inorganic layer comprising a metal, a metalloid, or a combination thereof, the inorganic layer having a thickness comprised between 1 and 100 nm; At least one second organic layer comprising at least one polymer that is marine biodegradable according to the ISO 22403:2020 standard or its equivalent ASTM D6691:2017 standard, the at least one polymer being selected from the list of polyhydroxyalkanoates (PHA), polycaprolactones (PCL), or combinations thereof, the at least one polymer having a density of 0.5 to 30 g / m 2 Preferably, the amount is 1 to 10 g / m 2 a second organic layer, the second organic layer being applied in an amount of from about 100 to about 1000 nm, the biodegradable polymer having a melting temperature comprised between about 30° C. and about 160° C.; This is achieved by a marine biodegradable metallized paper-based multi-layer packaging material comprising:

[0018] "Transfer metallization" means that an extremely thin layer of a metal or metalloid material is deposited on a support film, and then such layer is placed in contact with a target medium, such that the metal or metalloid layer is transferred to said target medium. Transfer metallization is known in the art and will not be described in further detail herein.

[0019] All components of the packaging material are certified for marine biodegradability in accordance with the principles of the present invention.

[0020] In one possible but optional embodiment, polyvinyl alcohol (PVOH), ethylene vinyl alcohol (EVOH), butenediol vinyl alcohol (BVOH), poly(butylene succinate-co-butylene adipate (PBSA), polybutylene adipate terephthalate (PBAT), polyhydroxyalkanoate (PHA), or copolymers or compounds thereof, can be added in very small amounts as part of the first organic layer or as part of the innermost layer (heat seal layer). These polymers should not exceed 1% of the total weight of the material. It is not marine biodegradable per se, except in very small amounts, which may be no more than 20% by weight of other organic marine degradable materials. For example, PBSA or PBAT can be blended with PHA in the heat seal layer in an amount not exceeding 20% ​​PBSA or PBAT to 80% PHA. However, the total content of such non-marine biodegradable polymers should not exceed a maximum amount, so that the overall structure still remains marine biodegradable. The above compounds have been found to improve interlayer adhesion and processability. The compounds are only optional.

[0021] Marine biodegradability can be certified, for example, according to the international standard ISO 22403:2020, or its equivalent ASTM D6691:2017, and through independent testing laboratories such as TUV Australia. More specifically, for example, ISO 18830 and ISO 19679 are two standards relating to test methods for measuring the aerobic biodegradation of non-buoyant plastic materials at the seawater / sediment interface, and are applicable for the certification of materials used in the structures and / or final products according to the invention.

[0022] The total thickness of the polymer coating layers in the structure is greatly reduced compared to the thickness of the paper material, as a result of which the inventors have achieved overcoming the technical limitations of known multi-layer barrier structures and realizing a packaging multi-layer structure having excellent barrier properties against oxygen and moisture transfer, as well as resistance to liquid contact from its inner or outer surfaces, while at the same time constituting a total content of cellulosic fibers, preferably up to 90% by weight of the total material.

[0023] The inventors have succeeded in forming a multi-layer structure completely free of polymer layers formed by extrusion lamination and / or adhesive lamination, thus providing a multi-layer structure with a ratio of cellulosic fibers to non-cellulosic materials and a very high fiber content. The polymer layer is easy to separate in the repulping process due to the solubility of the pre-coating layer in water and also due to the relatively low adhesion of the post-metallization (or post-metalloidization) polymer to the remaining part of the metallization layer. Thus, the resulting structure shows good repulping ability and high fiber yield, and is acceptable for waste paper collection in most countries. Due to the very low content of non-cellulosic polymer and vacuum-deposited metallic material, the entire material of the present invention is easily decomposed, dissolved and separated in recycling processes designed for cellulosic materials such as paper or cardboard, unlike existing multi-layer barrier structures known in the art.

[0024] Preferably, the biodegradable polymer of the second organic layer has a tensile strength of greater than 30 MPa and an elongation at break of greater than 850%.

[0025] Furthermore, at least one polymer of said first and / or second organic layer is preferably functionalized by grafting with maleic anhydride. Alternatively or simultaneously, at least one polymer of said first and / or second organic layer can be plasma activated.

[0026] Advantageously, the polyhydroxyalkanoate (PHA) of said at least one second organic layer may be blended with hardwood cellulose fibres, so that said compound comprises at least 50% cellulose fibres.

[0027] In a possible embodiment of the invention, the first organic layer optionally further comprises a mineral filler selected from the list of kaolin, calcium carbonate, talc, silica, wollastonite, clay, calcium sulfate fibers (also known as Franklin fibers), mica, glass beads, alumina trihydrate, and combinations thereof.

[0028] Preferably, the metal or metalloid inorganic layer is selected within the list of aluminum, aluminum oxide (AlOx), silicon oxide (SiOx), or alloys thereof.

[0029] Advantageously, the marine biodegradable packaging material of the present invention may further comprise an organic barrier layer coated between the first organic layer and the inorganic layer, said barrier layer having a thickness of 0.5 to 30 g / m 2 in the range of 1 to 15 g / m 2 The composition includes a layer of polyglycolide (PGA) polymer or cellulose fiber (nano- or microfibrillated) in an amount ranging from 0.1 to 100 μm.

[0030] The organic layer may be prepared as an aqueous solution or dispersion, or at a concentration of 30 g / m 2 Less than 15 g / m 2 It can be applied by extrusion of very thin layers having a thickness of less than 100 nm.

[0031] Furthermore, in addition to its inherent marine biodegradability, the packaging material of the present invention, thanks to its carefully selected organic and inorganic components and due to its high cellulose content, has been found to be recyclable as paper and / or carton in dedicated paper / carton recycling stream processes in most countries.

[0032] Last but not least, the packaging material according to the invention is not only marine biodegradable by construction, but also preferably has a biodegradability of less than 1 g / m 2 / day (measured at 23°C and 85% relative humidity) and / or 3 / m 2 It also features an oxygen transmission rate (OTR) of less than 1 / day bar (measured at 23°C and 50% RH).

[0033] Additionally, the material preferably has a strain at break under in-plane tensile load of up to 4% in the machine direction of the paper and up to 10% in the cross-machine direction.

[0034] The present invention further relates to a three-dimensional sealed packaging article made from the above-mentioned marine biodegradable metallized paper-based multi-layer packaging material, obtained by molding said packaging material, filling it with an edible product for human or animal consumption and then sealing it.

[0035] The present invention also relates to a marine biodegradable metallized paper-based multi-layer packaging material as described above for packaging edible products for human or animal consumption.

[0036] Finally, the present invention also relates to a packaged edible product comprising the marine biodegradable metallized paper-based multi-layer packaging material described above, filled with an edible product for food or for animal consumption.

[0037] As used herein, the words "comprises," "comprising," and similar words should not be construed in an exclusive or exhaustive sense. In other words, they are intended to mean "including, but not limited to."

[0038] Additional features and advantages of the present invention are described in, or will be apparent from, the following description of the presently preferred embodiments which take place in conjunction with the drawings. [Brief description of the drawings]

[0039] [Figure 1] 1 shows a first embodiment of a multi-layer structure according to the present invention. [Diagram 2] 2 shows a second embodiment of a multi-layer structure according to the invention.

[0040] [Mode for carrying out the invention] Generally, as used herein, "extrusion coating" refers to a process for providing a layer of polymer by using an extruder to force a molten thermoplastic resin (e.g., polyethylene) through a horizontal slot die onto a moving web of substrate (e.g., paper). The product is a permanently coated web structure.

[0041] "Extrusion lamination" refers to a process akin to extrusion coating in which a polymer resin is extruded between two substrates (eg, a layer of paper and another layer of polymer film) to act as a binder.

[0042] "Adhesive lamination" refers to a process in which one paper material is coated with an adhesive and laminated to a second paper or paperboard material.

[0043] In the lamination process, two thick layers of material are combined by either extrusion lamination or adhesive lamination, resulting in a thickness for each layer that is much greater than that obtainable by dispersion coating.

[0044] "Dispersion coating" refers to a coating technique in which an aqueous dispersion of fine polymer particles or a polymer solution is applied neat to the surface of paper or paperboard to form a solid, non-porous film after drying. Dispersion coating can be performed by gravure, flexo-gravure, rod, blade, slot die, curtain air knife, or any other known paper coating method. In dispersion coating, much thinner layers can be created than extrusion lamination and / or adhesive lamination because the polymer is mixed into an aqueous solution. This provides advantages in terms of polymer usage, its barrier performance, and recyclability of the resulting paper structure. The goal of dispersion coating is to achieve a barrier layer against water, water vapor, grease, oil, gas, etc., by an environmentally friendly coating. Another goal is to prepare the surface of the paper material for the vacuum deposition process.

[0045] "Plasma activation" means that the adhesion between two adjacent layers of a structure can be improved by subjecting the surface of at least one of the two adjacent layers of the structure to a process in which polymer functional groups are replaced with different atoms by ionization in the plasma. As a result, the surface energy of the plasma activated layer is generally increased. Alternatively, plasma activation can add bonds with other chemicals, decompose or break bonds, or crosslink materials.

[0046] In all possible embodiments of the present invention, and particularly in the exemplary embodiments specifically described below, the multi-layer packaging structure is biodegradable in a marine environment. Such biodegradability is achieved when the structure contains a cellulosic substrate and an ultra-thin inorganic layer containing only a few metal or metalloid atoms per square meter, and where all organic components are marine biodegradable polymers.

[0047] The biodegradability of the final structure is defined and tested under the international standards mentioned above, in particular the ISO 22403:2020 standard, or its equivalent, the ASTM D6691:2017 standard.

[0048] In addition to, or instead of, the inherent biodegradability, the multi-layer structure according to the present invention is preferably designed to be recyclable in paper stream processes as well.

[0049] Recyclability in the paper stream is achieved by the multi-layer structure of the present invention, wherein: The cellulose content is predominant relative to all components contained therein (the definition of recyclability in the paper stream varies by national legislation, but in most countries a material must contain at least 80% cellulose, preferably at least 90% cellulose, to be accepted in paper-specific recycling processes); and The inorganic layer is extremely thin (i.e., a few nanometers, typically 1-50 nm) and consists of a few atoms in thickness. The organic polymer layer is preferably deposited by coating or thin layer extrusion, meaning that the layer thus obtained is sufficiently thin relative to the thickness of the paper to achieve a very high paper content in the overall structure; Finally, any subsequent organic layers (second organic layer, third organic layer, etc.) deposited inside the metal or metalloid layer will be characterized by low cohesion and adhesion to the rest of the structure components, making the entire structure compatible with paper recycling processes such as those previously described herein.

[0050] FIG 1 illustrates a first embodiment of the present invention. In this embodiment, a multi-layer structure 1 is provided with, from its outer side to its inner side (i.e., the inner side in contact with the packaged product): Basis weight 62g / m 2 2. Very smooth paper layer of Mainly provides gas (especially oxygen) barrier properties, 3g / m 2 a first pre-metallization organic polyglycolide (PGA) coating layer 3 applied as an aqueous solution of an inorganic vacuum deposited layer 4 of aluminum having a thickness of 40 nm, which mainly provides water vapor barrier properties; and 5g / m 2 a second organic coating layer 5 of polycaprolactone (PCL) applied as an aqueous dispersion of It is equipped with:

[0051] The innermost polycaprolactone layer 5 functions as the heat-sealable layer in this first embodiment.

[0052] The inorganic layer 4 of aluminum can be deposited by a direct metallization process or by a transfer metallization process.

[0053] In this embodiment, the first and second organic layers are applied by aqueous dispersion coating techniques, which can improve the recyclability of the layers in the paper stream process.

[0054] The structure 1 of the first embodiment has an oxygen transmission rate (OTR) value of 1 cm measured at 23° C. and a relative humidity (RH) of 50%. 3 / m 2 / day and has a water vapor transmission rate (WVTR) of 1 g / m2 measured at 23°C and 85% RH 2 / day or less, achieving high moisture barrier property and gas barrier property.

[0055] The tensile strength of the polycaprolactone polymer used for the PCL layer 5 is measured at 33 MPa under standard test conditions (DIN EN ISO 527-1) and its elongation at break is measured at 910%. These values ​​provide good recovery properties that allow the aluminum layer to be protected during processing of the structure in conventional packaging formation processes. When producing a package from the material, no cracks in the aluminum layer occur during bending, stretching and / or sealing of the material, so that the OTR and WVTR barrier levels are maintained equally before and after the package is formed from the multi-layer structure material.

[0056] As an alternative to this first embodiment, the innermost PCL dispersion coated heat seal layer may be a 9 g / m2 PCL dispersion coated heat seal layer applied by aqueous dispersion coating or extrusion coating. 2 The heat seal layer may be replaced by a protein-based heat seal layer (eg, casein) or a polyhydroxyalkanoate (PHA) heat seal layer having a thickness of 0.1 to 1.0 mm.

[0057] Alternatively, the PHA heat seal polymer can be blended (ie, compounded) with a specific amount of hardwood cellulose fibers to provide a higher cellulose content throughout the structure, thereby improving marine biodegradability.

[0058] In figure 2 a second embodiment of a paper-based barrier multi-layer packaging structure 1 according to the invention is shown.

[0059] In this second embodiment, the multi-layer structure is, in order from its exterior to its interior (i.e., the interior in contact with the packaged product): Basis weight 62g / m 2 2. Very smooth paper layer of A first organic coating layer 3 of a PHA polymer, optionally functionalized by plasma activation treatment, optionally incorporating 30-70% by weight of hardwood cellulose fibers, said first organic polymer being 3 g / m 2 an organic coating layer 3 applied as an aqueous solution in an amount of an organic barrier layer 6 of microfibrillated or nanofibrillated cellulose polymer that has been plasma activated for functionalization, the organic barrier layer 6 being applied as a tie layer to bond the first organic layer 3, which is outside the metal coating, to the outside of the next inorganic layer described below, the tie layer 6 being at 1 g / m2 as an aqueous dispersion; 2 It is applied in an amount of A 40 nm thick vacuum deposited inorganic (aluminium) layer 4 is then applied, followed by A second organic layer 5 acting as a second layer on the inside of the metallization, on the inside of the inorganic layer 4, and having a thickness of 5 g / m 2This is followed by a second organic layer 5 comprising a polycaprolactone (PCL) polymer applied as an aqueous dispersion in an amount of 1000g / g.

[0060] Alternatively, the organic tie layer 6 may include polyglycolide polymer (PGA) instead of micro / nanofibrillated cellulose, or marine biodegradable polyvinyl alcohol (PVOH).

[0061] As an alternative to aluminum in the inorganic layers, metalloids can be applied, either SiOx or AlOx.

[0062] As in the first embodiment, alternative polymers to PCL can be envisaged, provided that the recovery properties (tensile strength, elongation at break) correspond to the requirements set for implementing the invention, i.e. the polymer has a tensile strength value of more than 30 MPa and an elongation at break of more than 850%. Alternatively, this PCL layer can be replaced by a layer of polyhydroxyalkanoate (PHA) or of a protein base such as casein.

[0063] A structure corresponding to the above embodiment meets the requirements for marine biodegradability of the material or packaging made from it under standard conditions.

[0064] A preferred manufacturing process comprises the following steps in order: First, the paper support material is covered with a marine biodegradable first organic (outer than the metal coating) layer by extrusion coating or dispersion coating, and then This latter can be directly metallized (with or without prior plasma activation) or can be coated by the passage of a second cellulose-based suspension or biopolymer dispersion, thus forming an additional barrier layer between the first organic layer and the next layer, and then The resulting structure is metallized, optionally after plasma activation according to known plasma activation techniques, and then The metallized structure is covered with an extrusion coated biopolymer layer or directly coated with a biopolymer dispersion.

[0065] In all of the above embodiments of the present invention, the multi-layer structure may include other additional layers and optional layers therein that are not described in full detail. Such layers may include, for example, a printing layer on the outer surface of the paper layer, and optionally a protective layer that is deposited on the outside of the printing layer and thus constitutes the outermost layer of the entire structure. The printing layer and the optional protective layer are techniques known to those skilled in the art, and therefore will not be described in more detail.

Claims

1. A marine biodegradable and recyclable metallized paper-based multi-layer packaging material (1), comprising, in order from the outside to the inside, 30-120g / m ２ A paper layer (2) having a basis weight falling within the range At least one first organic layer (3) comprising at least one polymer that is marine biodegradable according to the ISO 22403:2020 standard or its equivalent ASTM D6691:2017 standard, said at least one polymer being selected from the list of polyhydroxyalkanoates (PHA), microfibrillated or nanofibrillated cellulose, polyglycolide (PGA), or combinations thereof, said at least one polymer having a molecular weight of 0.5 to 15 g / m ２ Preferably, the amount is 1 to 7 g / m ２ and said biodegradable polymer has a melting temperature comprised between 160° C. and 200° C., preferably between 170° C. and 180° C.; a vacuum-deposited or transferred metallized inorganic layer (4) comprising a metal, a metalloid or a combination thereof, the inorganic layer (4) having a thickness comprised between 1 and 100 nm; At least one second organic layer (5) comprising at least one polymer that is marine biodegradable according to the ISO 22403:2020 standard or its equivalent ASTM D6691:2017 standard, said at least one polymer being selected from the list of polyhydroxyalkanoates (PHAs), polycaprolactones (PCLs), protein-based extrusion grades or dispersions, or combinations thereof, said at least one polymer having a molecular weight of 0.5 to 30 g / m ２ , preferably 1 to 10 g / m ２ a second organic layer (5) applied in an amount of from 30° C. to 160° C., said biodegradable polymer having a melting temperature comprised between 30° C. and 160° C. A metallized paper-based multi-layer packaging material comprising:

2. 2. The metallized paper-based multilayer packaging material (1) according to claim 1, wherein the biodegradable polymer of the second organic layer (5) has a tensile strength of more than 30 MPa and an elongation at break of more than 850%.

3. 3. The metallized paper-based multilayer packaging material (1) according to claim 1 or 2, wherein at least one polymer of the first and / or second organic layer is functionalized by grafting with maleic anhydride.

4. 3. The metallized paper-based multilayer packaging material (1) according to claim 1 or 2, wherein at least one polymer of the first and / or second organic layer is plasma activated.

5. 5. The metallized paper-based multi-layer packaging material (1) according to any one of claims 1 to 4, wherein the polyhydroxyalkanoate (PHA) of the at least one second organic layer is blended with hardwood cellulose fibers, such that the blend comprises at least 50% cellulose fibers.

6. 6. The metallized paper-based multi-layer packaging material (1) according to any one of claims 1 to 5, wherein the first organic layer (3) further comprises a mineral filler selected from the list of kaolin, calcium carbonate, talc, silica, wollastonite, clay, calcium sulfate fibers (also known as Franklin fibers), mica, glass beads, alumina trihydrate, and combinations thereof.

7. 7. The metallized paper-based multilayer packaging material (1) according to any one of claims 1 to 6, wherein said metal or metalloid inorganic layer (4) is selected in the list of aluminium, aluminium oxide (AlOx), silicon oxide (SiOx), or alloys thereof.

8. The present invention further comprises an organic barrier layer (6) coated between the first organic layer (3) and the inorganic layer (4), the tie layer (6) being made of a polyvinyl alcohol (PVOH) or polyglycolide (PGA) polymer at a concentration of 0.5 to 30 g / m ２ in the range of 1 to 15 g / m ２ The metallized paper-based multi-layer packaging material (1) according to any one of claims 1 to 7, comprising in an amount in the range of:

9. The organic layers (3, 5, 6) are each present as an aqueous solution or dispersion, or in a concentration of 30 g / m ２ less than 15 g / m ２ The metallized paper-based multi-layer packaging material (1) according to any one of claims 1 to 8, wherein the metallized paper-based multi-layer packaging material (1) is applied by extrusion of very thin layers having a thickness of less than 1000 nm.

10. The metallized paper-based multi-layer packaging material (1) according to any one of claims 1 to 9, wherein the packaging material is recyclable as paper and / or carton.

11. The packaging material is 1 g / m ２ / day (measured at 23°C and 85% relative humidity), and / or ３ / m ２ The metallized paper-based multilayer packaging material (1) according to any one of claims 1 to 10, having an oxygen transmission rate (OTR) of less than 100 / day bar (measured at 23°C and 50% RH).

12. 12. The metallized paper-based multi-layer packaging material according to any one of claims 1 to 11, wherein the packaging material has a strain at break under in-plane tensile load of up to 4% in the machine direction and up to 10% in the cross-machine direction of the paper.

13. A three-dimensional sealed packaging article made of the marine biodegradable metallized paper-based multilayer packaging material (1) according to any one of claims 1 to 12, obtained by moulding said packaging material, filling it with an edible product for human or animal consumption and then sealing it.

14. Use of the marine biodegradable metallized paper-based multilayer packaging material (1) according to any one of claims 1 to 12 for packaging edible products for human or animal consumption.

15. A packaged edible product comprising the marine biodegradable metallized paper-based multilayer packaging material (1) according to any one of claims 1 to 12 filled with an edible product for food or for animal consumption.

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