Biodegradable and compostable food packaging unit made of molded pulp or fluff pulp with laminated multi-layer piece and method for manufacturing such food packaging unit

Abstract

Biodegradable and compostable food packaging units made from a molded pulp or fluff pulp having a laminated multi-layer member and methods of making such food packaging units are disclosed. The present invention relates to a biodegradable food packaging unit made of a mold pulp or a fluff pulp and a method of manufacturing such a biodegradable packaging unit. A package according to the present invention comprises a food receiving and / or carrying compartment comprising a biodegradable laminated multilayer member comprising: an inner cover layer comprising an amount of biodegradable aliphatic polyester; a first intermediate layer of biodegradable material for connecting and / or sealing adjacent layers; a functional layer comprising a vinyl alcohol polymer; a second intermediate layer of biodegradable material for connecting and / or sealing adjacent layers; and an outer cover layer comprising an amount of a biodegradable aliphatic polyester, and wherein the food packaging unit is a compostable food packaging unit.

Description

[0001] This application is a divisional application of the application with the application number 201980048373.7, the filing date of 18 July 2019, and the invention title “Biodegradable and compostable food packaging unit made of moulded or fluff pulp material with laminated multi-layer and method of manufacturing such food packaging unit”.

[0002] The present invention relates to a food packaging unit made of moulded or fluff pulp material. Such food packaging unit can relate to a box, a carton, a cup, a tray, a carrier, a siplid, etc.

[0003] Packaging units made of moulded pulp are known. Such moulded paper pulp or fluff paper pulp is often derived from recycled paper material and / or virgin fibres. These packaging units are used for storing, transporting and / or displaying a range of products, including food products such as eggs, tomatoes, kiwis.

[0004] Packaging units that come into contact with food products are subject to many restrictions. This often requires the provision of an additional film layer on or in the packaging unit, which film layer acts as a barrier. This barrier separates the food product from the moulded pulp of the packaging unit.

[0005] One of the problems of such food packaging units comprising an additional film layer is that the packaging unit is often not sustainable, or at least not fully sustainable. Furthermore, the use of such additional film layer also limits the possibility of recycling.

[0006] It is an object of the present invention to eliminate or at least reduce the above-mentioned problems in conventional food packaging units and to provide a more sustainable and / or a food packaging unit with improved possibilities of recycling.

[0007] To this end, the present invention provides a food packaging unit made of moulded or fluff pulp material, the packaging unit comprising a food-receiving and / or carrying compartment, the compartment comprising a biodegradable laminated multi-layer, the multi-layer comprising: - an inner cover layer comprising an amount of biodegradable aliphatic polyester; - a first intermediate layer of biodegradable material for connecting and / or sealing adjacent layers; - a functional layer comprising a vinyl alcohol polymer; - a second intermediate layer of biodegradable material for connecting and / or sealing adjacent layers; and - an outer cover layer comprising an amount of biodegradable aliphatic polyester, and wherein the food packaging unit is a compostable food packaging unit.

[0008] The food packaging unit according to the present application comprises a compartment capable of receiving or carrying or containing a food product. For example, the food receiving compartment can relate to a compartment capable of containing a food product such as an egg, a tomato, a kiwi, or a container for containing a beverage. The carrying compartment can relate to a carrying surface on or in which a food product can be placed, such as a plate, a cup, a bowl, a bottle divider, etc. In other embodiments according to the present application, the food receiving compartment is capable of receiving and containing a meal, such as a ready-to-eat meal, a salad, etc.

[0009] In the context of the present application, degradable relates to degradation resulting in loss of properties, whereas biodegradable relates to degradation resulting from the action of microorganisms such as bacteria, fungi and algae. Compostable relates to degradation by biological processes to produce CO2, water, inorganic compounds and biomass.

[0010] The food packaging unit according to the present application is preferably compostable, thereby providing a sustainable packaging unit. For example, this provides a biodegradable alternative to conventionally used plastics. This improves the recyclability of the packaging unit made from a molded pulp or fluff pulp (including so-called virgin fiber material and / or recycled fiber material) and comprising a biodegradable laminate. In several presently preferred embodiments of the present application, the packaging unit is also marine degradable, thereby further improving the sustainability of the packaging unit.

[0011] According to the present application, the food packaging unit comprises a biodegradable laminated multilayer piece. In some presently preferred embodiments of the present application, such laminated multilayer piece is provided on or at a food contact surface of the food receiving and / or carrying compartment. In some other embodiments of the present application, the laminated multilayer piece is provided in a molded pulp or fluff pulp of the food receiving and / or carrying compartment.

[0012] According to the present invention, the laminated multi-layer piece comprises at least 5 material layers. It is to be understood that additional layers can also be provided according to the present invention. The inner and outer cover layers comprise an amount of biodegradable aliphatic polyester, such as PBS, PHB, PHA, PCL, PLA, PGA, PHBH and PHBV. The inner and outer cover layers can also comprise a biodegradable material composition, for example a combination of starch and one of the aforementioned biodegradable aliphatic polyesters (e.g. PBS and / or PLA). This improves the surface properties of the laminated multi-layer piece and of the packaging unit provided with the laminated multi-layer piece. This includes the so-called wipeability of the packaging unit. Wipeability relates to the possibility to remove stains from the surface and to reduce or even prevent stains from penetrating into the material. Furthermore, it can provide more possibilities to mask (hide) unwanted stains and / or to facilitate the compostability of the packaging unit. The surface properties are also related to the grease resistance, for example, so that the (chemical properties) of the packaging unit can be maintained during its use. Furthermore, the penetration of oil from food products such as pasta or fries into the food packaging unit can be reduced. Furthermore, for example, the water barrier properties can be improved to reduce the penetration of water into the packaging unit, thereby reducing the problem of bulging.

[0013] Furthermore, the laminated multi-layer piece comprises a functional central layer comprising a biodegradable and compostable ethylene vinyl alcohol polymer. This functional layer contributes to the multi-layer piece properties, for example acting as a gas barrier. For example, the functional layer can provide an effective O2 barrier. This increases the shelf life of the food product in the packaging unit.

[0014] In the presently preferred embodiment, the ethylene vinyl alcohol polymer comprises a highly amorphous ethylene vinyl alcohol polymer, for example HAVOH and / or butanediol ethylene vinyl alcohol copolymer (BVOH). This polymer or polymer mixture also provides an effective barrier, in particular a gas barrier, more specifically an oxygen barrier. This barrier can be effectively used to further increase the shelf life of the food product. Furthermore, this also reduces food waste, thereby further increasing the sustainability effect of the food packaging unit according to the present invention. Experiments show a surprisingly effective O2 barrier compared to conventional materials, in particular at relative humidity up to 60%. An example of BVOH is G-Polymer.

[0015] As a further advantage, the ethylene vinyl alcohol polymer is moldable and extrudable. This makes it possible to co-extrude the laminated multi-layer piece with the base material of the packaging unit, in particular the base material of the compartment (e.g. a molded pulp or fluff pulp). The co-extruded material can be molded or deep-drawn. This provides an efficient and effective manufacturing process for the packaging unit of the present invention. The efficiency can even be further increased by recycling the remaining parts after the punching of the material into the manufacturing process.

[0016] The inner and outer cover layers are separated from the central functional layer by an intermediate layer, which can also be referred to as a tie layer. This intermediate layer is generally a biodegradable material and connects and / or seals its adjacent layers. Preferably, the intermediate layer improves or at least contributes to maintaining the desired properties of the central functional layer, for example acting as a gas barrier. For example, the intermediate layer seals the central functional layer against liquid penetration to maintain the gas barrier properties of the functional layer.

[0017] It will be appreciated that additional separation layers can be provided in the laminated multilayer piece, providing 7, 9 or 11 layers of material to improve the overall performance of the laminated multilayer piece, for example including a grease barrier and an odor barrier.

[0018] The results show that by applying the laminated multilayer piece, the overall performance of the packaging unit is improved. In fact, the packaging unit with the laminated multilayer piece enables the compartment to accommodate different kinds of food, including for example ready-to-eat meals with pasta sauce.

[0019] The combination of barrier properties and wipeability of the laminated multilayer piece in the packaging unit according to the present application enables these packaging units to be used for many various different food products, for example including meat packages. In fact, the packaging unit of the present application generally prevents staining in the product caused by hemoglobin contained in the meat. This improves the visual appearance of the product and the shelf life of the product.

[0020] Furthermore, the packaging unit according to the present application is compostable. This reduces waste and provides a more sustainable packaging of food products.

[0021] According to the present invention, the packaging unit having a food receiving and / or carrying compartment is made from a molded pulp or fluff pulp. In a presently preferred embodiment, a laminated multi-layer piece is co-extruded with the molded pulp and then deep drawn into the desired shape of the packaging unit. In another presently preferred embodiment, the laminated multi-layer piece is provided in an in-mold operation, preferably in combination with an in-mold drying operation. Alternatively, the laminated multi-layer piece is laminated onto the molded pulp or fluff pulp, optionally including one or more of the following: negative pressure / vacuum deep drawing, heating, providing an overpressure at the top side. The multi-layer piece according to the present invention shows an effective ability to be deep drawn in the packaging unit. In an alternative embodiment, a (raw) fluff pulp is used, preferably including long fiber softwood. After pre-treatment, the fluff pulp is provided for an air-laid flow. In order to provide the fluff pulp to the mold, a binder can be used, for example as a spray or foam. This reduces the amount of water used in the manufacturing process of conventional molded fiber (packaging) products. In fact, in conventional molded pulp products, water is used as a carrier. Avoiding the need for water as a carrier significantly reduces the amount of water required in the manufacturing process. This results in a significant reduction of the energy required to dry the resulting product. Furthermore, this significantly reduces the carbon footprint of the final product manufactured according to the method of the present invention. By providing the fluff pulp to the mold, a three-dimensional shaped product can be manufactured. In order to provide the laminated multi-layer piece to the fluff pulp, one or more of the aforementioned or other process steps can be applied, including co-extrusion and lamination. The air-laid process step preferably further includes a so-called spunlaid process. In a presently preferred embodiment of the present invention, a barrier layer is provided to the three-dimensional shaped mold. This makes it possible to manufacture a product of fluff pulp and a laminated multi-layer piece having a barrier material in one mold. This increases the efficiency of the manufacturing process. Furthermore, providing the fluff pulp and the barrier material in the same mold and subjecting them to heating and / or pressing / pressure treatment improves the adhesion of the materials. This provides additional strength and stability to the final product.

[0022] In a presently preferred embodiment, the laminated multi-layer piece having a functional barrier layer is provided as an intermediate layer between two layers of fluff pulp or molded pulp. In this embodiment, the barrier layer is encapsulated to some extent by the fluff pulp or molded pulp layers. Optionally, further layers are provided to further enhance the performance and properties of the final product.

[0023] In a presently preferred embodiment of the present invention, the laminated multi-layer piece having a functional barrier layer is provided on one side of the product, i.e. on the food contact surface of the compartment. This can reduce the overall wall thickness of the final product compared to the embodiment having an encapsulated barrier layer.

[0024] Preferably, the material of the packaging unit is sufficiently refined to further enhance the desired properties. In particular, a refining energy of about 150 kWh / ton of material shows good results. As a further effect, a total weight reduction of the packaging unit of up to about 20% can be achieved compared to conventional products such as CPET or PP trays or the like, without affecting the strength and stability of the packaging unit. Optionally, additional additives can be added to further improve the performance of the packaging unit. For example, an amount of AKD can be provided to improve the water resistance.

[0025] As a further advantage, the packaging unit with the laminated multi-layer piece makes it possible to provide the packaging unit with a paper-like appearance and paper-like feel. This improves the perception of the packaging unit by the consumer.

[0026] When applying the laminated multi-layer piece, a further advantage is the provision of a thermal insulation effect to the food packaging unit. This is particularly relevant in case of heating of a ready-to-eat meal with a magnetron, for example, a conventional packaging unit is heated to a temperature of up to 90-100°C, whereas a similar packaging unit provided with the laminated multi-layer piece is heated to a temperature of up to 50-70°C. This increases the safety of using such a meal. Experiments have shown that the temperature resistance of the packaging unit can be up to 200°C, even up to 220°C. This improves the so-called “cool-to-touch” property of the packaging unit. This prevents the consumer from being injured when removing the packaging unit from the oven. More specifically, “cool-to-touch” relates to an external packaging temperature in the range of 10-30°C after heating the product in the oven, for example. This is a lower temperature compared to a conventional CPET packaging unit, for example. Thus, the packaging unit according to the present invention is safer in use.

[0027] As a further advantage, the packaging unit with the laminated multi-layer piece maintains the biodegradable and / or compostable properties of the packaging unit, as it eliminates the need for using fluorine-containing compounds required in conventional packaging units, for example, in the production of disposable tableware. The production of disposable tableware is, for example, the production of Chinet disposable tableware. Thus, the packaging unit according to the present invention improves the sustainability of handling food products. In fact, this enables the decomposition of the food packaging unit as a whole. In such a preferred embodiment, the food packaging unit can be decomposed at home, such that the food packaging unit can be composted at home. Such a compostable-at-home packaging unit further improves the overall sustainability of the packaging unit of the present invention. This enables the replacement of the use of less sustainable materials in the food packaging unit, such as CPET, PP, PE, PS, aluminum.

[0028] Another advantage of providing a packaging unit with a multilayer element according to the present invention is that modified atmospheric conditions can be applied within the packaging unit. The barrier properties preferably act in both directions: from outside to inside and vice versa. This allows, for example, the creation of so-called MAP products, which can further increase shelf life.

[0029] In a presently preferred embodiment, the laminated multilayer member is a coextruded laminated multilayer member. Coextrusion enables the construction of a layered member comprising multiple sublayers by melting, extruding, and joining separate layers. In a presently preferred embodiment, the laminated multilayer member is melted or fused to a compartment that receives and / or holds food. Preferably, the laminated multilayer member is disposed on a food-contacting surface of the compartment to enhance the shelf life of the food.

[0030] In a presently preferred embodiment, the packaging unit includes a biodegradable aliphatic polyester layer on the food contact surface to improve the melting and / or fusion of the laminated multilayer piece thereon. This provides a good connection between the compartment and the laminated multilayer piece and also maintains the compostable properties of the packaging unit according to the present invention. In fact, this optional biodegradable material layer is used as a bonding agent connected between the laminated multilayer piece and the packaging unit. This also improves the strength and stability of the laminated multilayer piece and the packaging unit as a whole. The thickness of this thin layer is preferably in the scope of 1μm to 100μm.

[0031] Alternatively, or in addition, the laminated multilayer is melted and protrudes into and / or is integrated into the molding paste or fluff paste matrix.This provides the material matrix of the packaging unit with desired properties.

[0032] By providing heating step, further improved the biodegradable aliphatic polyester fiber that the multilayer piece of lamination melts and / or is fused to the molding slurry or the fluff slurry.In fact, heating step has improved the adhesion / connection of the multilayer piece of lamination to the packaging unit.This heating step can be carried out in a press, and this press pushes the multilayer piece of lamination onto the food contact surface, pushes into suitable shape.Selectively, in a present preferred embodiment of the present invention, the multilayer piece of lamination is arranged in the mould, and wherein packaging unit is made by molding slurry.The multilayer piece of lamination is arranged on the packaging unit in mould.The food packaging unit with the multilayer piece of lamination can be dried in mould, relates to so-called in-mold drying operation, or can selectively dry in an additional independent drying step after product is discharged from mould.

[0033] Additionally, or as an alternative, a spray coating may be applied to improve the water and / or grease resistance.Preferably, the emulsion is sprayed onto the packaging unit, forming a film layer during processing of the packaging unit.

[0034] Optionally, the laminated multi-layer piece is provided by applying a pre-stress to the laminated multi-layer piece. In another embodiment, to reduce the risk of providing a laminated multi-layer piece with a reduced thickness in the corners of the packaging unit, the laminated multi-layer piece is designed and shaped according to the desired dimensions and then provided to the packaging unit. This can involve cutting the design of the laminated multi-layer piece and folding it onto the food contact surface. Thereafter, in a presently preferred embodiment, a heating step is performed to melt or fuse the materials together.

[0035] Many food packaging units are provided with a cover or seal or film to cover the compartment of the food product. Another problem with conventional food packaging units relates to such a top sealing film, which needs to be handled separately from the other parts of the packaging unit. This needs to be taken into account when handling the packaging unit and / or increases the risk of mixed waste streams.

[0036] According to a preferred embodiment of the present application, the packaging unit can comprise a biodegradable top sealing film. Providing such a biodegradable top sealing film provides a fully biodegradable and compostable packaging unit for the food product. This improves the disposal possibilities of the material, thereby avoiding the risk of mixed waste streams. Furthermore, it reduces the amount of residual waste. This significantly improves the sustainability of the food packaging industry.

[0037] Preferably, the packaging unit is provided with a peripheral edge comprising a connection surface for the top sealing film, which connection surface is substantially free of the laminated multi-layer piece.

[0038] This edge or alternative connection surface enables the top sealing film to adhere to the compartment of the packaging unit. In some embodiments, the packaging unit is provided with a (transparent) seal, foil, film, sheet or liner that closes the opening of the packaging unit. In fact, this layer acts as a closure for the packaging unit. The use of biodegradable aliphatic polyesters (such as PBS and / or PLA) in the packaging unit facilitates the adherence of this closure to the packaging unit. In fact, the biodegradable aliphatic polyesters (partly) act as an adhesive or glue.

[0039] It has been shown that this facilitates hot seal peelability, i.e. removal of the transparent layer after heating of the packaging unit in the microwave, for example, and / or cold seal peelability, i.e. removal of the transparent layer before heating when the packaging unit is taken out of the fridge, for example.

[0040] Optionally, a thin layer of biodegradable aliphatic polyester is provided to adhere the transparent layer to the edges of the packaging unit. Preferably, the transparent layer is also home compostable. In a presently preferred embodiment, the transparent layer comprises a mixture of PBS, PHBT and / or PLA in an amount. Optionally, a thin anti-fog layer is provided to improve the transparency of the layer. Further, optionally, the transparent layer comprises PVOH in an amount to improve the performance related to O2permeability. This can be advantageously applied to packaging units for meat and meat products, for example.

[0041] In a presently preferred embodiment of the present application, the top sealing film further comprises one or more biodegradable aliphatic polyesters. This can improve the adhesion of the top sealing film to the laminated multi-layer piece and / or to the molded pulp or fluff pulp. Optionally, a separate adhesion layer is provided.

[0042] In a presently preferred embodiment of the present application, the thickness of the individual layers is in the range of 1.5 pm to 50 pm, preferably in the range of 1.5 pm to 30 pm, and wherein the total thickness of the laminated multi-layer piece is in the range of 20 pm to 150 pm. These layers provide a laminated multi-layer piece with an acceptable thickness and providing effective barrier properties, for example.

[0043] In a presently preferred embodiment of the present application, the thickness of the functional layer is in the range of 1.5 pm to 10 pm, and most preferably in the range of 3 pm to 5 pm. For the individual layers, the thickness of the intermediate layer is preferably also in the range of 1.5 pm to 10 pm, and most preferably in the range of 1.5 pm to 3 pm. The thickness of the inner and outer cover layers is preferably in the range of 20 pm to 50 pm, more preferably in the range of 20 pm to 40 pm. It will be appreciated that different combinations of layers and thicknesses can be made. It is presently preferred that the total thickness of the biodegradable multi-layer piece is in the range of 23 pm to 70 pm, more preferably in the range of 30 pm to 60 pm, even more preferably in the range of 30 pm to 50 pm, and most preferably the thickness is about 40 pm.

[0044] In a further presently preferred embodiment, the thickness of the functional layer is in the range of 1.5 pm - 10 pm, and most preferably in the range of 3 pm - 5 pm. For the individual layers, the thickness of the intermediate layer is preferably also in the range of 1.5 pm - 10 pm, and most preferably in the range of 1.5 pm - 3 pm. The thickness of the inner and outer cover layer is preferably in the range of 20 pm - 50 pm, more preferably in the range of 30 pm - 40 pm. It is to be understood that different combinations of layers and thicknesses can be applied. It is presently preferred that the total thickness of the biodegradable multilayer piece is in the range of 70 pm - 100 pm, more preferably in the range of 70 pm - 90 pm, and most preferably the thickness is about 80 pm. It has been shown experimentally that an effective barrier, in particular an oxygen barrier, with a lower weight can be applied economically efficient. In embodiments of the packaging unit with a top sealing film, this top sealing film is preferably provided with a similar multilayer piece construction, and a thickness in the range of 25 pm - 100 pm, more preferably in the range of 30 pm - 50 pm. The thickness of the intermediate layer and the functional layer is preferably similar to the multilayer piece, while the inner and outer cover layer is provided with a reduced thickness. In many applications, a reduced thickness of the top sealing film is possible compared to a laminated multilayer piece, as the top sealing film does not need to be deep drawn in the manufacturing process.

[0045] In another preferred embodiment of the present application, the amount of biodegradable aliphatic polyester in the food packaging unit is in the range of 0.5% - 20% by weight, more preferably in the range of 1% - 15% by weight.

[0046] By applying an amount of biodegradable aliphatic polyester in one of the above ranges, the sustainability and the packaging properties of the food packaging unit according to the present application are significantly improved. The biodegradable aliphatic polyester is provided in the laminated multilayer piece and / or in the matrix of the molded pulp or fluff pulp and / or as a separate layer on the compartment.

[0047] In another preferred embodiment of the present application, the amount of biodegradable aliphatic polyester is in the range of 2% - 10% by weight, preferably in the range of 5% - 9% by weight, most preferably in the range of 6.5% - 8% by weight.

[0048] Applying an amount of biodegradable aliphatic polyester in these ranges provides a packaging unit that is both stable and robust.

[0049] Another advantage when using biodegradable aliphatic polyesters in a food packaging unit is that the size is constant or dimensionally stable.

[0050] As a further advantage of using biodegradable aliphatic polyesters, the so-called heat sealing capability of the packaging unit is improved. This further improves the food packaging properties.

[0051] A further advantage of the introduction of an amount of biodegradable aliphatic polyester in the food packaging unit is that the performance of the packaging unit can be adjusted by mixing or blending the main biodegradable aliphatic polyester with other polymers or agents. Furthermore, biodegradable aliphatic polyester materials can be prepared for (paper) coating and printing. Moreover, in some embodiments, digital printing can be applied to the laminated tray to reduce the overall cost of the packaging unit. This further improves the sustainability of the packaging unit. Furthermore, a paper look can be achieved.

[0052] As mentioned before, the food packaging unit can comprise one or more additional agents in addition to the use of biodegradable aliphatic polyester. This enables a specific design of the properties and performance of the food packaging unit according to the specifications or needs of the customer, taking into account the specific food product.

[0053] Preferably, the biodegradable aliphatic polyester comprises an amount of one or more of PBS, PHB, PHA, PCL, PLA, PGA, PHBH and PHBV. Preferably, the use of biodegradable aliphatic polyester is combined with the use of additional additives or substances aimed at improving or achieving specific performance of the packaging unit. In a further presently preferred embodiment, the biopolymer applied is derived from so-called non-gmo (non-genetically modified) biopolymers. For example, it has been shown that the use of PLA in addition to another biodegradable aliphatic polyester can improve the strength and stability of the packaging unit, thereby providing a more robust packaging unit and / or requiring less raw materials.

[0054] According to a preferred embodiment of the present application, the biodegradable aliphatic polyester comprises an amount of PHBH. Experiments have shown that the temperature properties are improved, increasing the manufacturing possibilities by providing acceptable properties up to 200°C and even up to 220°C.

[0055] According to an alternative preferred embodiment of the present application, the biodegradable aliphatic polyester comprises an amount of polybutylene succinate (PBS). PBS is one of the biodegradable aliphatic polyesters. PBS can also be referred to as polytetramethylene succinate. PBS naturally decomposes into water, CO2 and biomass. The use of PBS as a compostable material contributes to providing a sustainable product.

[0056] The use of PBS is possible in food contact applications comprising a food packaging unit made from a molded pulp. An advantage of the use of PBS is that the decomposition rate of PBS is much higher than other agents or ingredients such as PLA (e.g. including variants thereof such as PLLA, PDLA and PLDLLA).

[0057] Thus, the use of PBS in a food packaging unit made from molded pulp significantly increases the sustainability of the packaging unit. This increases the likelihood of recycling and makes the packaging unit biodegradable or compostable. For example, the use of PBS in the lid seal can avoid the need for non-compostable PE as an inner liner.

[0058] In another preferred embodiment of the present invention, the laminated multi-layer piece comprises a colorant.

[0059] By providing a colorant, the visual appearance of the packaging unit of the present invention can be improved. Furthermore, this can be used to provide additional information to the consumer. For example, Indian meals can be provided with a red packaging unit, and Italian food can be provided with a green packaging unit. It will be appreciated that these examples can be extended to other exchange of information with the consumer.

[0060] Preferably, the colorant is biodegradable, and more preferably compostable. This keeps the entire packaging unit biodegradable, and even compostable.

[0061] Optionally, additionally or as an alternative, the colorant is added to the molded pulp or fluff pulp, preferably a soluble dye. These agents can be cationic or anionic, also known in another classification as basic dyes, direct dyes or acid dyes. In the presently preferred embodiment, cationic colorants are used. Optionally, the molded pulp or fluff pulp can be colored using additives, dyes (basic dyes, direct dyes, anionic and / or cationically charged dyes), pigments or other components that provide color to the packaging unit. This enables the packaging unit to be provided with a color that is representative of its (intended) content.

[0062] In another preferred embodiment of the present invention, the laminated multi-layer piece comprises a print. By providing the laminated multi-layer piece with a print, the possibility of providing additional information or extended prints to the consumer is provided.

[0063] In the presently preferred embodiment, the print is provided in mirror image on the pulp facing side of the laminated multi-layer piece, such that the print can be seen from the (other) food side of the laminated multi-layer piece. This reduces the risk of the printed ink coming into contact with the food.

[0064] The food packaging unit according to the present application is biodegradable as a whole. More preferably, the unit is biodegradable at a temperature in the range of 5°C to 60°C, preferably in the range of 5°C - 40°C, more preferably in the range of 10°C - 30°C, even more preferably in the range of 15°C - 25°C and most preferably at a temperature of about 20°C. This renders the decomposition of the packaging unit easier. Furthermore, this enables a so-called environmental decomposition or home decomposition of the packaging unit according to the present application. For example, the packaging unit according to the present application can be industrially and / or home compostable according to EN 13432.

[0065] In one embodiment of the present application, the test with the packaging unit shows home compostability, wherein the packaging unit is decomposed according to acceptable practical standards within 24 weeks.

[0066] Optionally, the biodegradable aliphatic polyester (such as PBS) can be manufactured from fossil resources. More preferably, the biodegradable aliphatic polyester (such as PBS) is bio-based and made from, for example, plant resources. This bio-based biodegradable aliphatic polyester (such as PBS) further improves the sustainability of the food packaging unit.

[0067] In another embodiment of the present application, the packaging unit further comprises an amount of natural fibers and / or alternative fibers.

[0068] The provision of an amount of natural fibers and / or alternative fibers provides the packaging unit with a natural feel and / or improves the overall strength and stability of the packaging unit. Such natural fibers / alternative fibers can include fibers from different sources, in particular biomass fibers from plant sources. Such biomass from plant sources can relate to grasses, including grasses, sugar cane, bamboo and cereals including barley and rice. Other examples of biomass from plant sources are solanaceous plants, including tomato plants of which the leaves and / or stems can be used, for example plants from the family of Arecaeae, including palm oil plants of which the leaves can be used, for example plants from the Order Maphighiales, including flax, plants from the family Rosaceae, including ramie, plants from the family Malvaceae, including cotton, kenaf and jute. Alternatively, or in addition, the biomass from plant sources includes so-called herbal plants, which, in addition to grasses and some of the above-mentioned plants, also include jute, banana (including banana), amaranth plants and the like. In addition or as an alternative, biomass material derived from peat and / or moss can be applied.

[0069] Preferably, the plant-derived (lignocellulosic) biomass comprises biomass derived from plants of the family Poaceae (also known as the grass family). This family includes grasses, including grass and barley, corn, rice, wheat, oat, rye, reed, bamboo, sugar cane (where residues from sugar processing can be used, also known as bagasse), milo (sorghum), rapeseed, other cereals, etc. In particular, the use of so-called natural grasses provides good results in the manufacture of packaging units such as egg packages. For example, such natural grasses can be derived from the natural landscape. Plants of this family have shown good manufacturing possibilities and provide a sustainable product for the consumer.

[0070] Preferably, in an embodiment of the application, the packaging unit comprises an amount of microfibrillated cellulose (MFC), sometimes also referred to as nanofibrillated cellulose or cellulose nanofiber. The MFC is preferably derived from plant-derived cellulose raw material. The use of MFC enhances the fiber-to-fiber bonding strength and further improves the strengthening effect. Although MFC is preferably used in combination with one or more of the biodegradable aliphatic polyesters, MFC can also be used as a replacement for these components.

[0071] In an embodiment of the application, the biopolymer and / or the MFC provides a biofilm on or at the surface (part of the surface) of the packaging unit. Experiments have shown that good barrier properties can be obtained. Alternatively, or in addition thereto, a paper-like appearance and / or a paper-like surface layer can be provided. For example, a paper layer can be sealed to a thin layer of the (bio)film, or a thin layer of the biofilm or biopolymer can be coated or laminated to a paper layer. For example, a biopolymer layer can be sealed to the surface of a tray or container for food. Such a paper-like appearance and / or paper-like surface layer contributes to the appreciation of the packaging unit according to this embodiment of the application by the consumer. Tests have shown good wet strength and barrier properties. The barrier properties can include oxygen and / or grease barrier. It is generally assumed that the oxygen barrier properties are achieved by the ability of the MFC to form a dense network involving hydrogen bonds.

[0072] Optionally, some hydrophobic elements are added to the MFC layer to further improve the water barrier properties. This can involve modification of the hydroxyl groups, for example chemical modification on the surface of the microfibrils and / or modification by absorption of polymers.

[0073] Another advantage of the use of MFC is that the printability, including the possibility of digital printing, is improved. In addition, or as an alternative, MFC can reduce the costs by reducing the weight or grams via an increase in the amount of filler. This can also enhance the optical properties.

[0074] It should be understood that the combination of MFC and / or biodegradable aliphatic polyester can further improve the mentioned effects and advantages. Furthermore, the combination with conventional polymer films, for example by coating the MFC and / or biodegradable aliphatic polyester thereon, can provide a product with the advantages of both types of materials.

[0075] The present invention also relates to a method of manufacturing a food packaging unit from a moulding pulp, the method comprising the steps of: - preparing an amount of a moulding pulp or fluff pulp; - providing a laminated multi-layer piece, the laminated multi-layer piece comprising: - an inner cover layer comprising an amount of biodegradable aliphatic polyester; - a first intermediate layer of biodegradable material for connecting and / or sealing adjacent layers; - a functional layer comprising an ethylene vinyl alcohol polymer; - a second intermediate layer of biodegradable material for connecting and / or sealing adjacent layers; and - an outer cover layer comprising an amount of biodegradable aliphatic polyester, - manufacturing the food packaging unit from the laminated multi-layer piece to provide a food packaging unit as a compostable food packaging unit.

[0076] This method provides the same effects and advantages as described in relation to the food packaging unit. According to the present invention, the laminated multi-layer piece can be provided before or after the release of the food packaging unit from the mould. In a presently preferred embodiment, the laminated multi-layer piece is co-extruded with the moulded pulp and then deep drawn into the desired shape of the packaging unit. In another presently preferred embodiment, the layer is provided in an in-mould operation, preferably in combination with an in-mould drying operation.

[0077] In another preferred embodiment, the method comprises the additional step of subjecting the packaging unit to a heating step, which heats the packaging unit to a temperature of about the melting temperature of the biodegradable aliphatic polyester, to cross-link / interact with the laminated multi-layer piece, thereby increasing the strength and improving the barrier properties. Preferably, the heating step heats the temperature of the packaging unit to a heating temperature in the range of 145-195 °C, preferably in the range of 165-190 °C, and most preferably to a temperature of about 180 °C.

[0078] In another preferred embodiment of the invention, a step of refining at least a part of the fibers of the molding pulp or batt pulp is made. It turns out that a higher degree of refining results in more and / or stronger bonds between the fibers. This increases the strength of the packaging unit and / or reduces its weight. Preferably, the refining of the molding pulp or batt pulp is made together with the biodegradable aliphatic polyester. The refining step improves the mixing of the materials and fibrillates the fibers. Refining the fibers can reduce the fiber length, fibrillate the fibers, thereby providing a more specific surface of fiber branches, which improves the bonding and hydrogen bridge formation, resulting in a stronger, stiffer product. In fact, this increases the number and strength of the connections between the molding pulp or batt pulp and the biodegradable aliphatic polyester, resulting in an improved overall strength and stability of the packaging unit. This is even further improved when the refining step is combined with a heat treatment step to activate the biodegradable aliphatic polyester.

[0079] In a preferred embodiment of the invention, the packaging unit can be negatively charged, for example in or after the refining step. In order to enhance the adhesion of the laminated multilayer piece and / or the top sealing film, an ionization step can be made to remove or at least reduce the negative charge.

[0080] By adding an amount of biodegradable aliphatic polyester to the molding pulp or batt pulp, the packaging unit can be made from a blend comprising fibers and biodegradable aliphatic polyester, and / or a separate layer comprising biodegradable aliphatic polyester can be realized. Such separate or additional layer can improve the fusing or melting process.

[0081] The method according to the invention provides a more sustainable food packaging unit than conventional packaging units that are molded for food products. Optionally, other biological materials can be used in combination with the main biodegradable aliphatic polyester, for example starch and other polyesters, such as PBS, PLA or similar biodegradable components. Such combinations or alternatives can provide similar effects and advantages as described with respect to the packaging unit.

[0082] Preferably, in the molding step of the food packaging unit, the biodegradable aliphatic polyester is connected to the cellulose fibers of the molding pulp. This provides a food packaging unit with sufficient strength. In the presently preferred embodiment, these connections are realized by activating the biodegradable aliphatic polyester. This can involve subjecting the packaging unit to approximately the melting temperature of the biodegradable aliphatic polyester, for example 145-175 °C. More specifically, the biopolymer melts and crosslinks / interacts with the laminated multilayer piece to increase the strength and change properties such as barrier properties.

[0083] In some presently preferred embodiments, the method further comprises the step of providing a top sealing film, preferably a top sealing film that is biodegradable and / or compostable.

[0084] In one presently preferred embodiment, the method further comprises the step of performing a (dry) sterilization and pasteurization on the (filled) packaging unit. In particular, in combination with the (O2) barrier properties of the laminated multi-layer piece (and the top sealing film), the shelf life of the food product is significantly increased. Moreover, the O2 barrier prevents or at least reduces oxidation processes in the food, thereby contributing to the preservation of the taste of the food.

[0085] In the life cycle of the packaging unit, in the context of the present invention, the manufacturing process of the food packaging unit preferably further comprises the step of biodegrading the packaging unit. Hence, in relation to the present invention, preferably, the biodegradation of the packaging unit is also considered to be part of the entire manufacturing process. From a sustainability point of view, biodegradation is an important component of the life cycle.

[0086] Preferably, the biodegradation comprises the decomposition of the food packaging unit.

[0087] More preferably, the decomposition is performed at a temperature in the range of 5-40 °C, preferably in the range of 10-30 °C, more preferably in the range of 15-25 °C, most preferably at about 20 °C, thereby relating to ambient decomposition.

[0088] In presently preferred embodiments, the biopolymer applied originates from so-called non-gmo (non-genetically modified) biopolymers.

[0089] In some preferred embodiments, the method further comprises the step of refining the fibers used for molding the pulp or fluff pulp and / or adding an amount of natural fibers. This provides the same or similar effects and advantages as described in relation to the packaging unit. BRIEF DESCRIPTION OF DRAWINGS

[0090] Further advantages, features and details of the present invention are elucidated based on preferred embodiments of the present invention, with reference to the accompanying drawings, wherein: - Figure 1A and Figure 1B a packaging unit for receiving a food product according to the present invention is shown; - Figure 1C and Figure 1D an alternative packaging unit according to the present invention is shown; - Figure 1E a detail of the laminated multi-layer piece is shown; - Figure 2 a plate as a food receiving product according to the present invention is shown.

[0091] -Figure 3A and Figure 3B A packaging unit according to the invention is shown, comprising PBS and / or another biodegradable aliphatic polyester; - Figure 4 An example of an alternative food packaging product according to the present invention is shown; - Figure 5 shows a further packaging unit for a bottle divider according to the invention; and - Figure 6A and 6B shows a further packaging unit according to the invention; - Figure 7A and 7B shows a packaging unit for eggs according to the invention; and - Figure 8 Experimental results of a conventional packaging unit and a packaging unit according to the present invention are shown.

[0092] Packaging unit 2 ( Figure 1A ) relates to a food receiving container having a bottom portion 4 and a side wall 6 defining an opening 8. A laminated multilayer element 10 comprising a compostable vinyl alcohol polymer is provided on the inside of the container 2. In the illustrated embodiment, the laminate 10 includes printed indicia 12. Preferably, in the illustrated embodiment, the printed indicia is provided on the rear side of the laminated multilayer element 10.

[0093] In the illustrated embodiment, the container 2 is provided with a peelable top sealing film 13a ( Figure 1A ). Edge 13b is shown peeled away from edge 13c of container 2. In this embodiment, top sealing film 13a is shown as a transparent film. It should be understood that film 13a can also be configured as opaque, or alternatively, as translucent and / or partially transparent. Alternatively, container 2 can also be configured without top sealing film 13a.

[0094] In the illustrated embodiment, the laminated multilayer member 10 ( Figure 1B ) includes a food-facing side 14 and a packaging side 16. In the illustrated embodiment, portions 18 can be removed or cut from the sheet or layer 10 according to specifications to allow the laminated multilayer member 10 to be processed to the desired size and to enable the layer 10 to be positioned inside the container 2. This allows the laminated multilayer member 10 to be properly positioned relative to the corners 20. In the illustrated embodiment, the printed indicia 12 is provided in a mirrored manner on the packaging side 16 of the laminated multilayer member 10 so that the displayed printed indicia 12 is visible to the user or consumer.

[0095] Packaging unit 22 ( Figure 1CAnother embodiment of a food-receiving container is provided having a bottom portion 24 and a sidewall 26 that bounds an opening 28. The packaging unit 22 has a length L, a width W and a height H. On the inside of the container 22 a laminated multi-layer piece 30 is provided, optionally comprising printed indicia. In the illustrated embodiment the laminated multi-layer piece 30 is provided on the inside of the packaging unit 22 and extends from the bottom portion 24 all the way to a profile or edge 32. The profile or edge 32 is at a small distance from the upper side of the edge 34. This distance is preferably in the range of 1 mm to 12 mm. The edge 34 Figure 1D is provided with a width W1 that bounds a contact surface 36 for connecting to the schematically illustrated liner or seal 33. In the illustrated embodiment this liner or seal 33 is connected directly to the molded pulp, optionally with an adhesive, instead of to the laminated multi-layer piece 30. Such an adhesive preferably comprises an amount of biodegradable polyester, for example PLA. In the illustrated embodiment the width W1 is in the range of 1 mm to 15 mm, preferably in the range of 2 mm to 5 mm.

[0096] The packaging unit 22 Figure 1C comprises a first denesting element 38 and a second denesting element 40. In the illustrated embodiment the denesting elements 38, 40 enable a stack of packaging units 22 to be denested. The denesting elements 38, 40 are designed asymmetrically. It will be understood that alternative denesting elements can also be envisaged according to the invention, either as an alternative or in combination. These alternative denesting elements can be designed asymmetrically or symmetrically. Asymmetric denesting elements enable the packaging units 22 to be denested in one direction, but not in the other direction or at least make denesting more difficult. The denesting elements 38, 40 have the additional advantage that they do not significantly alter the dimensions of the contact surface 36 and / or the internal volume of the packaging unit 22. In the illustrated embodiment the denesting elements 38, 40 are provided at or near the edge 34. This prevents the provision of markers, edges, protrusions, notches, etc. on or near the bottom portion 24. Such irregularities on or near the bottom portion 24 can hamper the cleaning or emptying of the packaging unit 22. In the illustrated embodiment an optional top seal film 42 is provided.

[0097] The laminated multi-layer piece 10 Figure 1E comprises a first cover layer 10a, a first intermediate layer 10b, a central functional layer 10c, a second intermediate layer 10d and a second cover layer 10e. It will be understood that other layers can be added to the multi-layer piece 10. It will be understood that the laminated multi-layer piece 10 can be applied to the container 2, but also to the packaging unit 22, more specifically to the food contact surface of the bottom portion 24 and its sidewall 26.

[0098] In another embodiment, the plate 50 is provided with a laminated multi-layer piece 52 on the food-receiving side. In the illustrated embodiment, the underside or backside 54 of the plate 50 is not provided with such a laminated multi-layer piece. Optionally, the plate 50 is provided with a top sealing film 56, for example in case the plate 50 accommodates a salad or a soup. It will be appreciated that other food products can also be accommodated by the plate 50. The multi-layer piece 52 is preferably similar to the already illustrated multi-layer piece 10. Figure 2

[0099] The packaging unit 102 carries or accommodates eggs and comprises a cover portion 104 and a bottom portion 106. In the illustrated embodiment, the packaging unit 102 comprises a laminated multi-layer piece 101. The multi-layer piece 101 is preferably similar to the already illustrated multi-layer piece 10. The bottom portion 106 is provided with a back surface 108, side surfaces 110 and a front surface 112 as well as a bottom surface 114. The cover portion 104 is provided with a back surface 116, side surfaces 118, a front surface 120 and a top surface 122. In the illustrated embodiment, a transition 124 is provided between the top surface 122 and the back surface 116 and between the top surface 122 and the front surface 120. Figure 3A 3B In the illustrated embodiment, the top surface 122 of the cover portion 104 is provided with a recess 126 comprising a plurality of openings 128. The openings 128 are delimited by two adjacent arched edges 130, 132, which have a larger thickness than the average thickness of the cover portion 104.

[0100] The side surfaces 118 of the cover portion 104 are provided with ejection notches or ejection elements 134. In the illustrated embodiment, the bottom portion 106 is provided with similar elements 136, which are mirrored with the ejection elements 134. A hinge 138 connects the back surface 116 of the cover portion 104 with the back surface 108 of the bottom portion 106. A lock 140 comprises a nose-like locking element 142, which is connected to a flap 144 of the bottom portion 106. The cover portion 104 is provided with an opening 146, which captures the locking element 142, thereby delimiting the lock 140.

[0101] In the illustrated embodiment, the bottom portion 106 is provided with a plurality of product-receiving compartments 148, a cone 150 and a partition wall 152. The cone 150 extends in an upward direction from the bottom of the bottom portion 106. The cover portion 104 comprises a cone support 154. The inner surface 158 of the packaging unit 102 comprises PBS and / or PLA material, optionally as a film layer, or alternatively blended and / or integral with the fibers of the molded pulp.

[0102] In the illustrated embodiment, the bottom portion 106 is provided with a plurality of product-receiving compartments 148, a cone 150 and a partition wall 152. The cone 150 extends in an upward direction from the bottom of the bottom portion 106. The cover portion 104 comprises a cone support 154. The inner surface 158 of the packaging unit 102 comprises PBS and / or PLA material, optionally as a film layer, or alternatively blended and / or integral with the fibers of the molded pulp. ​​

[0103] In the illustrated embodiment, the packaging unit 102 includes twelve product receiving compartments 148 arranged in two rows of six compartments 148. The individual compartments 148 are separated from one another by walls 152 and cones 150. It will be appreciated that other configurations are contemplated in accordance with the present invention.

[0104] The packaging unit 102 may also be configured to receive other products, such as tomatoes, kiwis.

[0105] It will be appreciated that other types of food packaging units are also contemplated according to the present invention.

[0106] Packaging unit 202 ( Figure 4 ) comprises a laminated multilayer element 201 disposed on a base portion 204 and a cover portion 206. Multilayer element 201 is preferably similar to multilayer element 10 already illustrated. Unit 202 is provided with a biodegradable aliphatic polyester, such as PBS and / or PLA, and is capable of containing a quantity of ice cream. Cover portion 206 comprises a top seal 208 of a layer or film 210 of a biodegradable aliphatic polyester, with an optional (paper) label. Fiber 212 may optionally be included in cover portion 206. This increases the possibility of imparting a natural paper feel and / or appearance to the unit. This can also be applied to other types of packaging units. For example, in ready meals or fast food, it allows the conventional sleeve to be omitted from the packaging unit. This results in a more cost-effective packaging unit with a possible weight reduction.

[0107] Packaging unit 202 has numerous applications, including but not limited to airline meals. These meals are delivered to aircraft after (dry) sterilization and pasteurization. Combined with the (O₂) barrier properties of the laminated multilayer element (and the top sealing film), the shelf life of the food product is significantly improved. Furthermore, the O₂ barrier prevents or at least reduces oxidation in the food, thereby helping to preserve its flavor.

[0108] As another example, the bottle divider 302 ( Figure 5 ) is illustrated as having a laminated multilayer element 301. Multilayer element 301 is preferably similar to multilayer element 10 already illustrated. In addition, bottle divider 302 may include an additional layer of PBS film (and / or a suitable alternative biodegradable aliphatic polyester), and / or may include an amount of PBS blended into the molding pulp.

[0109] Another example according to the present invention is a cover 402 provided with a laminated multilayer member 401, such as a cover for an ice cup ( Figure 6A Another example of a packaging unit according to the present invention is a sip cap 502 provided with a laminated multilayer piece 501 ( Figure 6B). The cover 402 and the sip-lid 502 comprise an additional film layer of biodegradable aliphatic polyester and / or can comprise an amount of biodegradable aliphatic polyester that is blended into the molded pulp. This results in the cover 402 and the sip-lid 502 being water resistant or liquid repellent and / or improves the heating step to melt or fuse the laminated multi-layer piece 401, 501 on or to the cover 402 and / or the sip-lid 502. Another advantage of using biodegradable aliphatic polyester is to reduce or prevent liquid from entering or migrating into the sip-lid material during use. Another advantage is dimensional constancy or dimensional stability. In this particular case, this prevents the sip-lid 502 from coming loose from a cup or mug for hot beverages (e.g. coffee, tea or soup) or cold beverages (e.g. carbonated drinks) and prevents the cover 402 from coming loose from e.g. an ice-cup. It will be appreciated that this lid 502 can also be applied to other food containers. For example, the lid 502 can be applied to a container for e.g. a milk shake. Further details and examples of the lid 502 are disclosed in WO 2010 / 064899, including embodiments with specific flanges and notches.

[0110] In addition to the laminated multi-layer piece 501, the sip-lid 502 is preferably coated with a biodegradable aliphatic polyester liner, such as a PBS liner, to improve the meltability. As mentioned, the sip-lid 502 can be used for cups and milk shakes. In addition, the sip-lid can be applied to so-called ready-meal trays (e.g. for pizza, wraps, fish, meat, lobster, pasta...), and e.g. act as a (digital) printable seal and barrier seal.

[0111] It will be appreciated that other designs for the packaging unit can be envisaged in accordance with the present application. For example, the container 602, 702 (Fig. 6) Figure 7A and 7B Fig. 6 illustrates different designs of an egg carton that is capable of containing eggs P and comprises a laminated multi-layer piece 601, 701. The multi-layer piece 601, 701 is preferably similar to the already illustrated multi-layer piece 10.

[0112] Other examples of food packaging products can relate to cup holders, cups, plates and other tableware, etc.

[0113] When manufacturing the food packaging unit 2, 50, 102, 202, 302, 402, 502, 602, a moulded pulp is prepared. Optionally, an amount of biodegradable aliphatic polyester, such as PBS and / or PHBH, is blended or mixed into the moulded pulp, and / or an amount of biodegradable aliphatic polyester, such as PBS and / or PHBH, is included in a separate layer, which is provided in or on the unit 2, 50, 102, 202, 302, 402, 502, 602. This separate layer can improve the contact with the laminated multi-layer 10, 52, 101, 201, 301, 401, 501, 601, which optionally comprises an ethylene vinyl alcohol polymer, such as HAVOH and / or BVOH. Preferably, the laminated multi-layer is co-extruded with the moulded pulp and is deep drawn. Further, or as an alternative, a raw unit is moulded. Optionally, the raw unit is dried in the mould using an in-mould drying process. In such alternative embodiments, the laminated multi-layer 10, 52, 101, 201, 301, 401, 501, 601 is provided in the mould and a heating step is performed. Optionally, an additional layer of biodegradable aliphatic polyester is provided to improve the contact between the packaging unit and the laminated multi-layer. Finally, the product is released from the mould.

[0114] Several post-drawing or post-moulding operations related to the unit 2, 50, 102, 202, 302, 402, 502, 602 can optionally be performed, including but not limited to: labelling, including in-mould labelling; marking, including printing and digital printing; testing. In several preferred embodiments, the compostable laminated multi-layer 10, 52, 101, 201, 301, 401, 501, 601 is at least arranged on the food contact area of the product containing part of the packaging unit. In preferred embodiments, the film is capable of being used as a so-called ovenable film in a microwave or oven. Preferably, the layer 10, 52, 101, 201, 301, 401, 501, 601 is capable of withstanding temperatures up to 170°C, 190°C or even higher. The biodegradable aliphatic polyester preferably comprises an amount of PBS and / or MFC and / or biodegradable aliphatic polyester, which can comprise an amount of one or more of PHB, PHA, PCL, PLA, PGA, PHBH and PHBV. In particular, the combination of the compostable packaging unit involving extrusion and / or in-mould drying further improves sustainability compared to conventional packaging units. The (digital) printable properties enable printing of packaging and / or food properties / information. This can for example avoid the use of a separate sheath. Further, it enables applying printed markings on the packaging unit, such as fish and chips (newspaper) printed markings.

[0115] One or more of the illustrated food packaging units provided with the laminated multi-layered article 10, 52, 101, 201, 301, 401, 501, 601 have been experimented. These experiments involved the "in-use" properties of the food packaging units in comparison with conventional packaging units, as well as the compostable properties. An amount of biodegradable aliphatic polyester was added to the molding slurry and a refining step was performed. The measurements were performed at a temperature of about 23°C and a relative humidity of about 50%. The measurements involved compression tests. This showed a significant increase in the compression values. For example, a packaging unit with 7.5% PLA and a refining step showed compression values of 450N-500N, whereas for a similar conventional product under the same conditions, the value was about 180N. Even under sub-optimal conditions of a relative humidity of about 90%, the compression values of the packaging units according to the present application were about 250N-270N, thus still superior to conventional products under their optimal conditions.

[0116] In further tests, the multi-layered article was applied to a food packaging unit and exposed for 24 hours at 23°C and a relative humidity of about 50%. No oxygen permeation was detected.

[0117] Further tests were also performed to show the dual ovenable (oven and microwave) performance of the packaging units according to the present application. In the experiments, the laminated product was heated to a temperature of about 190°C for about 30 minutes. The results showed that the film layers remained intact and did not melt. No leakage was detected. In addition, the strength and stability of the packaging units were not significantly affected. As a further effect, the packaging units were more stable against distortion when removing the packaging units from the oven (distortion is typically encountered with conventional packaging units). In addition, the packaging units of the present application showed a limited temperature increase of about 50°C-70°C, whereas conventional units reached a temperature of about 90°C-100°C under similar conditions. Other experiments with (food) trays showed even higher heat resistance when the trays were heated to a temperature of 180°C-200°C, and in addition showed (improved) resistance / rejection to oil, acid and moisture.

[0118] Further tests were performed to show the performance of the packaging unit according to the application by heating the packaging unit in an oven and / or microwave. In the experiment, a laminated product comprising laminated layers with a total thickness of about 40 pm was heated to a temperature of about 180 °C for about 35 minutes. The results showed that the film layer remained intact and did not melt. No leakage was detected. In addition, the strength and stability of the packaging unit were not significantly affected. As a further effect, the packaging unit was more stable against distortion when removing the packaging unit from the oven (distortion is often encountered with conventional packaging units). The film layer was tested for leakage by using food simulants such as 95% ethanol, modified polyphenylene oxide (MPPO), 2,2,4-trimethylpentane, etc. This test thus showed the safe use of the laminated product as a packaging, for example a food packaging.

[0119] Additional tests compared the temperature on the outside of the product packaging after cooking ("hands not hot") of different types of meals by heating in a microwave and an oven between a conventional packaging unit of CPET (crystalline polyethylene terephthalate) and a packaging unit of about 100% biodegradable made of molded fiber. The cooking of the ready-to-eat meals is explained as follows: - Microwave: 5 minutes at 700 watts; - Oven: 30 minutes at 180 °C (air heating).

[0120] To make the measurements, an IR (infrared) thermometer was used to observe the temperature on the outside of different parts of each tray / packaging unit.

[0121] The temperature of the food tray was measured periodically, directly after removal from the oven / microwave. The temperature results at the upper part of the tray are shown in Figure 8 These temperature results represent the entire packaging unit.

[0122] The results clearly show a considerable temperature difference of 10-15 °C, which indicates that the packaging unit according to the application is cooler when touched by the user. The food temperature in both packaging units was similar over the entire period. During the experiment, it was observed that the CPET tray became "wobbly" / unstable after heating. In addition, the biodegradable packaging unit was about 10% lighter than the CPET tray, while it was superior to this CPET tray.

[0123] In a further experiment, other properties were also examined. The results showed that the wipeability of the packaging unit could be improved. Further improvements could be shown by adding other additives.

[0124] Furthermore, shelf life tests were performed. In these tests, the packaging unit according to the application with the laminated multi-layer piece and the top-sealing film was compared with a conventional packaging unit for fresh meals. The tests showed a significant increase in shelf life from 8 days to 12 days. The present application is by no means limited to the preferred embodiments described above. The rights sought to be protected are defined by the claims appended hereto, and many modifications can be envisaged within the scope of the claims.

Claims

1. A food packaging unit made of fluff pulp, said packaging unit comprising a food receiving and / or carrying compartment, said food receiving and / or carrying compartment comprising a biodegradable laminated multilayer piece, said multilayer piece comprising: - an inner cover layer comprising an amount of biodegradable aliphatic polyester; - a first intermediate layer of biodegradable material, which serves to connect and / or seal adjacent layers; - a functional layer comprising a vinyl alcohol polymer; - a second intermediate layer of biodegradable material, which serves to connect and / or seal adjacent layers; and - an outer cover layer comprising an amount of a biodegradable aliphatic polyester, and wherein the food packaging unit is a compostable food packaging unit, The vinyl alcohol polymer includes highly amorphous vinyl alcohol polymer HAVOH and / or butanediol vinyl alcohol copolymer BVOH. 2 . The food packaging unit according to claim 1 , wherein the laminated multilayer is a coextrusion laminated multilayer.

3. The food packaging unit according to claim 1 or 2, wherein the laminated multilayer piece and the compartment are melted or fused together.

4. The food packaging unit of claim 3, wherein the packaging unit comprises a layer of biodegradable aliphatic polyester on the food contact surface to improve melting or fusing of the laminated multilayer thereon.

5. The food packaging unit according to any one of the preceding claims, wherein the laminated multilayer is melted in a matrix of moulding slip or fluff slip.

6. A food packaging unit according to any one of the preceding claims, further comprising a biodegradable top sealing film for covering the food receiving or carrying compartment.

7. The food packaging unit of claim 6, wherein the packaging unit comprises a peripheral edge comprising a connection surface for the top sealing film, the connection surface being substantially free of the laminated multilayer piece.

8. The food packaging unit of claim 6 or 7, wherein the top sealing film comprises a biodegradable aliphatic polyester.

9. The food packaging unit according to any one of the preceding claims, wherein the thickness of each layer is in the range of 5-50 μm, preferably in the range of 5-30 μm, and wherein the total thickness of the laminated multilayer is in the range of 20-150 μm.

10. The food packaging unit according to any of the preceding claims, wherein the amount of biodegradable aliphatic polyester in the food packaging unit is in the range of 0.5-20% by weight, more preferably in the range of 1-15% by weight.

11. The food packaging unit according to claim 10, wherein the amount of biodegradable aliphatic polyester in the food packaging unit is in the range of 2-10% by weight, preferably in the range of 5-9% by weight, and most preferably in the range of 6.5-8% by weight.

12. The food packaging unit of any one of the preceding claims, wherein the biodegradable aliphatic polyester comprises an amount of one or more of PBS, PHB, PHA, PCL, PLA, PGA, PHBH, and PHBV.

13. The food packaging unit of claim 12, wherein the biodegradable aliphatic polyester comprises an amount of PHBH.

14. The food packaging unit according to any one of the preceding claims, wherein the laminated multilayer comprises a colorant, which is biodegradable and more preferably compostable.

15. The food packaging unit according to any one of the preceding claims, wherein the unit is biodegradable at a temperature in the range of 5°C to 60°C, preferably in the range of 5°C to 40°C, more preferably in the range of 10°C to 30°C, even more preferably in the range of 15°C to 25°C, and most preferably at a temperature of about 20°C.

16. The food packaging unit according to any one of the preceding claims, wherein the biodegradable aliphatic polyester is bio-based.

17. The food packaging unit according to any one of the preceding claims, further comprising an amount of natural and / or alternative fibers.

18. A method of manufacturing a food packaging unit according to any one of the preceding claims from fluff slurry, the method comprising the steps of: - Prepare a certain amount of molding slurry or fluff slurry; - providing a laminated multilayer article, said laminated multilayer article comprising: - an inner cover layer comprising an amount of biodegradable aliphatic polyester; - a first intermediate layer of biodegradable material, which serves to connect and / or seal adjacent layers; - a functional layer comprising a vinyl alcohol polymer; - a second intermediate layer of biodegradable material, which serves to connect and / or seal adjacent layers; and - an outer cover layer comprising an amount of biodegradable aliphatic polyester, - manufacturing the food packaging unit from the laminated multilayer piece to provide a food packaging unit that is a compostable food packaging unit, The vinyl alcohol polymer includes highly amorphous vinyl alcohol polymer HAVOH and / or butanediol vinyl alcohol copolymer BVOH.

19. The method of claim 18, wherein providing the laminated multilayer member comprises the steps of: The layers are coextruded.

20. The method of claim 18 or 19, wherein the laminated multilayer piece and the compartments are melted or fused together.

21. The method according to claim 18, 19 or 20, further comprising the steps of: Supplied with biodegradable top sealing film.

22. The method according to any one of claims 18 to 21, further comprising the steps of: The packaging units are (dry) sterilized and pasteurized.

23. The method according to any one of claims 18 to 22, further comprising the steps of: The packaging unit biodegrades.

24. The method of claim 23, wherein biodegrading comprises decomposing the food packaging unit.

25. The method according to claim 24, wherein the decomposition is carried out at a temperature in the range of 5°C to 40°C, preferably in the range of 10°C to 30°C, more preferably in the range of 15°C to 25°C, and most preferably at a temperature of about 20°C.

26. The method according to any one of claims 18 to 25, further comprising the steps of: The fibers used for the molding pulp or fluff pulp are refined.

27. The method according to any one of claims 18 to 26, further comprising the steps of: Add a certain amount of natural fiber.

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