NL2022111B1

NL2022111B1 - Method for manufacturing a 3-dimensional shaped product from a fluff pulp material and a barrier material, and such product

Info

Publication number: NL2022111B1
Application number: NL2022111A
Authority: NL
Inventors: John Kuiper Harald
Original assignee: Huhtamaki Molded Fiber Tech Bv
Priority date: 2018-11-30
Filing date: 2018-11-30
Publication date: 2020-06-26

Abstract

The present invention relates to a method for manufacturing a 3-dimensional shaped product from a fluff pulp material and such product. The method according to the invention comprises the steps of: — providing a fluff pulp material; — providing an air-laid flow of fluff pulp material to a 3-dimensional shaped mould; — forming the product in the mould; and — releasing the layered 3-dimensional shaped product from the mould, Wherein a barrier layer is provided that comprises a biodegradable polymer layer and/or a cellulose-based layer.

Description

Method for manufacturing a 3-dimensional shaped product from a fluff pulp material and a barrier material, and such product The present invention relates to a method for manufacturing a 3-dimensional shaped product from a fluff pulp material. Such product may relate to packaging units for fruits and eggs, sip lids, covers, and inlay trays, for example.

Products such as packaging units having a 3-dimensional shape that are made from a moulded pulp material are known. Such moulded pulp often originates from recycled paper material and/or virgin fibres. These packaging units are shaped to store, transport and/or display a range of product, including food products such as eggs, tomatoes, kiwi’s.

One of the problems with such products is the amount of energy that is used for the manufacturing process that typically involves a significant drying step for the moulded product. Further problems are associated with barrier properties.

The present invention has for its object to obviate or at least reduce the above stated problem in conventional products that are manufactured from a moulded pulp material and to provide a 3-dimensional shaped product that is more sustainable having a lower carbon footprint and reducing the amount of energy that is required in the manufacturing process.

For this purpose, the present invention provides a method for manufacturing a 3- dimensional shaped product from a fluff pulp material, the method comprising the steps of: — providing a fluff pulp material; — providing an air-laid flow of fluff pulp material to a 3-dimensional shaped mould; — providing a barrier layer; — forming the product in the mould; and — releasing the layered 3-dimensional shaped product from the mould, wherein a barrier layer is provided that comprises a biodegradable polymer layer and/or a cellulose-based layer.

The method provides a 3-dimensional shaped product having a length, a width and a height according to certain specifications or requirements. Mostly, these specifications or requirements will be defined in accordance with the products that are carried in or by the product, for example.

In case a product that is manufactured according to the method of the present invention relates to packaging units for fruits and eggs, sip lids, covers, and inlay trays, the specifications or requirements are defined by the number and/or size and/or shape of the packed or carried 3- dimensional products. Preferably, the shaped product has a shape that relates to the products it is designed for. It will be understood that other shapes could also be envisaged in accordance to the invention.

The (raw) fluff pulp material preferably comprises long fibre softwoods. This material is often applied in personal care products. It will be understood that the fluff pulp material that is used in the manufacturing process according to the present invention may also comprise other components. The raw fluff pulp material is pre-treated to provide the fluff pulp material for the air- laid flow. Such pre-treatment may involve producing a more or less uniform sheet material that optionally comprises some additives. To provide the fluff pulp material to the mould a binder may be used. for example as a spray or foam. This reduces the amount of water that is used in the manufacturing process for a conventional moulded fiber (packaging) product. In fact, in conventional moulded pulp products water is used as a carrier. Obviating the need for water as a IO carrier significantly reduces the amount of water that is required in the manufacturing process. This results in a significant reduction of the energy that is required for drying the resulting products. Also, this significantly reduces the carbon footprint of the end-products that are manufactured according to the method of the present invention.

As a further advantage, the air-laid process enables a relatively high manufacturing rate due to the reduced requirements for a drying operation as compared to conventionally manufactured moulded pulp products. This further improves the overall efficiency of the manufacturing process.

By providing the fluff pulp material to a mould a 3-dimensional shaped product can be manufactured. Forming the product involves pressing the pulp material in the mould or moulds to shape the product. Forming may include additional heat treatments to activate and cure one or more of the additives that may be provided to the fluff pulp. This provides the end-product with sufficient strength and stability for its purposes. The type and amount of additives is preferably designed in accordance to the specific requirements of the manufactured product. The heat treatments are preferably performed in the mould, providing in-mould heat treatment of the manufactured product(s). Optionally, or in addition thereto, heat treatments are performed after releasing the product from the mould.

After releasing the product from the mould further treatments may be performed, including coating, labelling, and further processing steps. The air-laid processing step according to the manufacturing method of the invention preferably also includes so-called spun-laid processing.

Providing a barrier layer enhances the properties of the end-product. For example, the barrier layer may improve barrier properties for oxygen. This helps improving the shelf or storage life of products that are contained in the product.

In case a separate layer is provided this results in a sandwich structure of the end-product. In such structure the barrier layer is preferably provided on the food contact surface of the 3- dimensional shaped product, for example a food packaging unit.

Providing a barrier layer that comprises a biodegradable polymer and/or cellulose-based layer provides the product with appropriate barrier properties. The barrier layer is optionally provided to the [luff pulp material before moulding and/or after moulding. The barrier layer can be provided as a film layer, for example a biofilm layer, and/or a separate layer, for example a cellulose-based layer, or can be provided by other suitable methods such as spray coating.

In a presently preferred embodiment of the invention the biodegradable polymer comprises an aliphatic polyester, most preferably one or more of PBS, PHB, PHBH, PHA, PCL. PLA, PGA, and PHBV.

Experiments showed that such biofilm layer provides the product with appropriate barrier properties. For example, adding an amount of PLA and/or PBS and/or another biodegradable polymer in the range of 0-50 wt% of the final product, preferably 0.5-30 wt%, more preferably 2- 25 wt%, even more preferably in the range of 2-20 wt%, and most preferably in the range of 3-18 wt®%, improves the barrier properties. Preferably, a heat treatment is performed to activate and cure the biodegradable polymer(s) to achieve the desired effect. More preferably, the heat treatment is performed after the product has taken its desired shape by bringing the product with the biodegradable polymer layer to a temperature in the range of 145-175 °C to enable the biodegradable polymer fibres to distribute around the cellulosic fibres of the fluff pulp material. It will be understood that the actual process temperatures may depend on the composition of the pulp and biofilm material, for example.

A further advantage of adding an amount of biodegradable aliphatic polyester is that the packaging unit can also be decomposed using microorganisms in soil, for example. This enables decomposing the food packaging unit, comprising a biodegradable aliphatic polyester, as a whole. In such preferred embodiment, the food packaging unit can be decomposed at home, thereby rendering the food packaging unit home-compostable, Such home-compostable packaging unit further improves the overall sustainability of the packaging unit of the invention. This enables replacing the use of less sustainable materials, such as CPET, PP, PE, PS, aluminium in food packaging units.

The biodegradable aliphatic polyester can be mixed in the original moulded pulp material such that it is distributed over substantially the entire food packaging unit and/or can be provided as a separate layer on the side of the food packaging unit that may come into contact with a food product, for example.

Another advantage when using a biodegradable aliphatic polyester is the shape stability or dimensional stability that is achieved for the resulting 3-dimensional shaped product.

As a further advantage of the use of a biodegradable aliphatic polyester, the so-called heat seal ability of the 3-dimensional shaped product, such as a food packaging unit, is improved. This obviates or at least reduces the problem that the top seal/lidding film is not easy removablefrom the container/tray. This typically occurs when heating the packaging unit, for example in an oven and/or magnetron. Parts of the film may even end up in de food product. It was shown that by using a product in an embodiment of the invention the so-called peelability of the film is significantly improved such that the film can be removed easily. This provides a packaging unit that is user friendly, and reduces the risk of parts of the film ending up in the food product. It was further shown that the improved peelability was achieved under both heated (hot peel) and unheated (cold peel) conditions. Experiments showed that the packaging unit with such film remained its barrier functionality, while improving the peelability.

In addition to, or as an alternative for, the biodegradable polymer (film) layer, a cellulose-based layer can be provided. Preferably, the cellulose-based laminate layer comprises cellulose fibres that may originate from virgin {wood) fibers and/or recycled fibers and/or other suitable cellulose sources. Preferably, the cellulose fibres are hammered to improve their properties. Optionally, the laminate layer is prepared by exposing paper pulp to sulphuric acid and/or ZnCl, to provide a layer with high density, stability and heat resistance. Optionally, the layer can be siliconized to further improve its properties.

A further advantage of the present invention is the improvement of barrier properties. Barrier properties may include oxygen and/or grease barriers. Also, the penetration of oil originating from the food product, such as pasta or French fries, into the food packaging unit can be reduced. Furthermore, in the production of {Chinet) disposable tableware the fluorine chemistry can be reduced or even omitted from the manufacturing process. This provides a more sustanainable packaging unit for food products that still has an effective grease resistance and wipe ability. Also, water barrier properties can be improved to reduce the penetration of water into the packaging unit and thereby reducing ridging problems, for example.

It was shown that by applying a biodegradable polymer layer and/or a celhlose-based laminate layer the overall barrier properties of the 3-dimensional shaped product, such as a food packaging unit, were improved. This also relates to the so-called wipe ability of the packaging unit. Wipe ability relates to the possibility to remove stains from the surface and reducing or even preventing penetration into the material. These properties also relate to grease resistance such that the chemical properties of the packaging unit can be remained during its use.

Optionally, the barrier layer and/or mixture of pulp material with an amount of biodegradable polymer provides on both the inside (food contact) surface and on the outside surface of the packaging unit an effective wipe ability. In addition, this may improve the visual appearance of the packaging unit.

As a further advantage, providing a biodegradable polymer layer and/or cellulose-based laminate layer renders it possible to provide the 3-dimensional shaped product with a paper look and paper feel. This improves consumer perceptance of the packing unit.

As an even further advantage, the 3-dimensional shaped product with the biodegradable polymer layer and/or cellulose-based laminate layer maintains the biodegradability and/or compostable properties of the packing unit as it obviates the need for the use of fluorochemicals.

An even further advantage when applying a biodegradable polymer layer and/or a 5 cellular-based laminate layer is the insulating effect that is provided to the 3-dimensional shaped product. This is especially relevant in case of instant meals that are heated in a magnetron or oven, for example conventional packaging units heat up to a temperature of 90-100°C with the similar packaging unit that is provided with a biodegradable polymer layer and/or cellulose-based laminate layer heating up to 50-70°C. This improves the safety of using such meals. Experiments showed that it was possible to achieve a temperature resistance of the packing units up to 220°C. This improves the so-called “cool-to-touch” characteristic of the packaging unit. This is beneficial when heating the unit in an oven or microwave, for example. This prevents a consumer from being injured when removing a packaging unit from the oven with bare hands. More specifically, “cool- to-touch” relates to an outside packaging temperature in the range of 10-30 °C after heating the product in an oven, for example. This is a lower temperature as compared to conventional CPET packaging units, for example. Therefore, the packaging unit according to the invention is safer in use.

In one of the presently preferred embodiments of the invention the barrier layer comprises a first outer layer on a first side of the biodegradable polymer layer and/or cellulose- based layer, and a second outer layer on a second side of the biodegradable polymer layer opposite to the first side, wherein the first and second outer layers comprise one or more biodegradable polymers.

Providing a multiple layer structure as barrier layer provides an effective and efficient barrier. In particular, it enables designing the barrier layer in relation to the specific requirements that may depend on food characteristics and conditions, for example.

As a further effect, the middle or central biodegradable polymer layer and/or cellulose- based layer is shielded or protected by the outer layers. This enable providing a middle or central layer that provides an excellent gas barrier, however is relatively moisture sensitive. An example of such polymer is a vinyl alcohol polymer, such as HAVOH. This middle or central layer has a typical preferred thickness in the range of 5-10 micron.

In a presently preferred embodiment of the invention the barrier layer comprises an amount of vinyl alcohol polymer, wherein this vinyl alcohol polymer preferably comprises a highly amorphous vinyl alcohol polymer, such as HAVOH. Such polymer or polymer mixture also provides an effective barrier, especially a gas barrier, and more specifically an oxygen barrier.

Such barrier can effectively be used to improve the shelf-life of the food product(s) in the packaging unit, This reduces food waste.

In a preferred embodiment of the invention the first and second outer layer are connected or attached to the biodegradable polymer layer with a respective first and second adherence layer of a biodegradable material.

Providing an adherence layer improves the connection between the outer layer(s) and the (central) biodegradable polymer layer and/or cellulose-based layer. This multiple layer structure provides a strong and effective barrier layer. The adherence layer preferably comprises PLA, PBS, or a mixture thereof. The outer layers preferably comprise a biopolyester such as PLA, PHBH and more preferably a mixture of biodegradable polymers. The (central) biodegradable polymer layer preferably comprises a vinyl alcohol polymer, such as HAVOH, and/or a biopolyester such as PLA and/or a mixture of such biopolyesters.

According to one of the presently preferred embodiments of the invention the (food) packaging unit comprises a multiple layered barrier layer. This renders it possible to co-extrude the barrier layer and connect or attach it to the basic fluff pulp material of the packaging unit. The co- extruded material can be moulded or deep drawn in a next step. This provides efficient and effective manufacturing processes for the packaging unit of the present invention. The efficiency can even be improved further by recycling the remainders after punching the material into the manufacturing process. Alternatively, the barrier layer is provided to the fluff pulp material after shaping the fluff pulp material.

In a preferred embodiment of the invention a cellulose-based laminate layer is melted or fused with the biodegradable aliphatic polyester.

By providing a heat step the cellulose fibres are melted or fused to the biodegradable aliphatic polyester fibres. This improves the adherence/connection of the cellulose-based laminate layer to the packaging unit. This heating step can be performed in a press that pushes the laminate layer into the correct shape onto the food contact surface. Alternatively, in one of the presently preferred embodiments of the invention, the laminate layer is provided inside the mould wherein the package unit is manufactured from the moulded pulp material. The cellulose-based laminate layer is provided in the mould onto the packaging unit. The food packaging unit with the laminate layer can be dried in the mould involving a so-called in-mould drying operation or can alternatively be dried in an additional separate drying step after releasing the product from the mould.

The laminate layer can be provided applying pre-stress to the laminate layer. In another embodiment, to reduce the risk of providing a laminate layer with reduced thickness in the corners of the packaging unit, the laminate layer is designed and shaped according to the desired dimensions and thereafter provided to the packaging unit. This may involve cutting the design of the laminate layer and folding the laminate layer onto the food surface contact. Thereafter, in oneof the presently preferred embodiments, the heating step is performed to melt or fuse the materials together.

In a presently preferred embodiment of the invention the barrier layer is provided to the 3-dimensional shaped mould. This renders it possible to manufacture the product from a fluff pulp material and a barrier material in one mould. This improves efficiency of the manufacturing process. Furthermore, providing the fluff pulp material and barrier material in the same mould and performing a heat and/or pressing/pressure treatment improves adherence of the materials. This provides additional strength and stability to the end-product.

In one of the presently preferred embodiments the barrier layer is provided as an intermediate layer between two layers of fluff pulp material. In this embodiment the barrier layer is sort of encapsulated by the layers of fluff pulp material. Optionally, further layers are provided to further enhance the properties and characteristics of the end-product.

In an alternative embodiment of the invention the barrier layer is provided on one side of the product. This reduces the overall wall thickness of the end-product as compared to an embodiment with encapsulated barrier layer.

In the different embodiments of the invention, the barrier layer optionally comprises polyvinyl alcohol (PVOH) and/or ethylene vinyl alcohol (EVOH). PVOH and/or EVOH have relevant barrier properties for oxygen. These barrier materials can advantageously be applied in packaging units of food products, including meat products. However, presently the use as an alternative component, such as HAVOH, is preferred.

As a further advantage the products resulting from the manufacturing process of the invention are preferably bio-degradable. In a most preferred embodiment the resulting product is capable of being subject to ambient or at home decomposing. This further improves the sustainability of the resulting product and the manufacturing process.

Preferably, the (raw) fluff pulp material comprises defibrizing the raw material. This defibrizing is preferably performed in a hammer-mill, preferably after a shredding process. This enables achieving the desired material characteristics for the end-product, for example relating to strength and stability of this product.

In a presently preferred embodiment of the invention the method further comprises the step of compacting the fluff pulp material before providing it to the mould.

By compacting the fluff pulp the quality of the resulting end-product can be significantly improved. For example, this may increase the strength of the end-product and enable it carrying a fruit, egg, electronic device, for example.

In a presently preferred embodiment of the invention wherein the step of providing an air-laid flow of moulded pulp material comprises providing a blanket-shaped flow to the mould.

By providing a blanket-shaped flow to the mould an effective manufacturing process can be achieved. Preferably, a compacting step is performed to provide a blanket having a certain length and width, and also a more or less homogeneous thickness. This improves the homogeneity of the end-product. In a presently preferred embodiment the thickness of the blanket is in the range of 0.5 to 3.0 cm. It was shown that providing the fluff pulp material in a blanket shape to the mould with the blanket having a thickness in the mentioned range provides the end-product with an improved homogeneity. This improves the overall quality of the end-product.

Preferably, in the manufacturing process, the mould is heated to enable performing a further heat treatment. This is specifically relevant when making use of additives to improve the IO overall performance of the end-product. For example an amount of AKD or ASA sizing agent can be provided to improve the water repellence.

Furthermore, forming the product in the mould preferably comprises the step of punching the product out of the blanket-shaped flow and providing it to the mould. In this context, punching may involve cutting, pressing or any other forging step. This enables providing the desired amount of material to the mould, thereby reducing the variation in the end-products, for example.

In a presently preferred embodiment of the invention the method further comprises the step of feeding the remaining material to the providing step of the fluff pulp material. Effectively, this enables a return possibility to re-introduce the remaining material of the blanket-shaped flow into the material flow of the manufacturing process. This significantly reduces the amount of waste material from the manafacturing process. Furthermore, this provides the manufacturing process with fluff material that has already undergone some processing steps. This further improves the efficiency of the manufacturing process and further reduces the overall carbon footprint, for example.

In one of the presently preferred embodiments of the invention the method further comprises the step of mixing the fluff pulp material with pulp material originating from recycled paper material.

Combining the fluff pulp material with a recycled stream of recycled paper enables a cost effective manufacturing process by reducing the amount of virgin fibres in the manufacturing process. This further improves the sustainability of the overall manufacturing process. The amount of recycled fibres in the end-product may be in the range of 0-100 wt%, preferably lies in the range of 10-90 wt%, more preferably lies in the range of 25-75 wt%, and lies most preferably in the range of 30-65 wt%.

In one of the presently preferred embodiments of the invention the method further comprises the step of providing one or more additives to the fluff pulp material and/or the barrier material.

By providing one or more additives to the fluff pulp material and/or the barrier material the product characteristics of the end-product can be brought into conformity to the desired product characteristics.

Optionally, additives may relate to a binder to bind the fluff pulp and/or the barrier material. In addition or alternatively, the additives comprise one or more biodegradable polymers. Such polymer may enhance the product characteristics, for example strength, stability, robustness, oil and/or water resistance. The preferably applied biodegradable polymer preferably comprises a biodegradable aliphatic polyester, preferably one or more of PBS, PHB, PHBH, PHA, PCL, PLA, PGA, and PHBV. For example, adding an amount of PLA and/or PBS and/or another biodegradable polymer in the range of 0-25 wi%, preferably 0.5-20 wt%, more preferably 0.75-10 wt%, even more preferably in the range of 1-8wt%, and most preferably in the range of 2-5 wt%, to the pulp material improves the strength of the end-product. Preferably, a heat treatment is performed to activate and cure the additives to achieve the desired effect. More preferably, the heat treatment is performed after the fluff material is brought into the mould and into its desired shape.

For example, the fluff material is brought into the mould at a temperature of about 100 °C. After the product has taken its desired shape a heat treatment can be performed by bringing the product to a temperature in the range of 145-175 °C to enable the PLA fibres to distribute around the cellulosic fibres of the fluff pulp material. It will be understood that the actual process temperatures may depend on the composition of the pulp material, for example.

The biodegradable polymer is in some of the preferred embodiments of the invention mixed in the original pulp material such that it is distributed over substantially the entire product and/or can be provided as a separate layer on a surface of the product that may come into contact with a food product, for example.

A further advantage of the present invention is the improvement of barrier properties by using an additive. Barrier properties may include oxygen and/or grease barriers. Also, the penetration of oil originating from the food product, such as pasta or French fries, into the end- product can be reduced. Furthermore, in the production of (Chinet) disposable tableware the fluorine chemistry can be reduced or even omitted from the manufacturing process, for example. Also, water barrier properties can be improved to reduce the penetration of water into the packaging unit and thereby reducing ridging problems, for example.

In the context of this invention biodegradable preferably comprises decomposing and/or is performed at a temperature in the range of 5 to 60 °C, preferably in the range of 5 to 40 °C, more preferably in the range of 10 to 30 °C, even more preferably in the range of 15 to 25 °C, and most preferably at a temperature of about 20 °C.

For example, PBS decomposes naturally into water, CO; and biomass, thereby providing a biodegradable alternative material to plastics, for example. The use of PBS as a compostable material contributes to providing a sustainable product.

The use of a biodegradable polymer like PBS is possible in food-contact applications including food packaging units from a pulp material. As mentioned PBS has good biodegradable properties and PBS can be decomposed to H:O and CO». This improves recycling properties of the product that are made from fluff pulp material and comprise PBS and/or similar additive.

A further advantage of adding an amount of PBS and/or similar additive is that the end- product can also be decomposed using microorganisms in soil, for example. This enables decomposing the product comprising PBS and/or a similar additive as a whole. In such preferred embodiment, the food packaging unit can be decomposed at home. For example, the decomposition rate of PBS is much higher as compared to other agents or components such as PLA (including variations thereof such as PLLA, PDLA and PLDLL A, for example). Preferably, the use of biodegradable aliphatic polyester is combined with the use of further additives or substances that aim at improving or achieving specific properties of the packaging unit.

In further presently preferred embodiments the biodegradable polymers that are applied originate from so-called non-gmo (non-genetically modified organisms) biopolymers. The further increases the biological origin of the packaging product.

In a further embodiment of the invention the end-product comprises an amount of micro fibrillated cellulose (MFC) sometimes also referred to as nanofibrillar cellulose or cellulose nanofibers. MFC preferably originates from cellulose raw material of plant origin. The use of MFC enhances the fiber-fiber bond strength and further improves the reinforcement effect. Although MFC is preferably applied in combination with PBS and/or one or more of the biodegradable aliphatic polyesters, it is also possible to use MFC as an alternative to these components.

In an embodiment of the invention the bio-polymers and/or MFC provide a biotilm on or at (a part of) the surface of the product. Experiments indicate that good barrier properties can be achieved. Alternatively, or in addition thereto, a paper look and/or paper feel surface layer can be provided. This contributes to the consumer’s appreciation of the product according to such embodiment of the invention. Tests have shown a good wet strength and barrier properties. Barrier properties may include oxygen and/or grease barriers. It is believed that the oxygen barrier properties are achieved by the ability of MFC to form a dense network involving hydrogen bonds.

Optionally, some hydrophobic elements are added to an MFC layer to further improve the water barrier properties. This may involve modification of the hydroxy! groups, for example on the surface of the micro fibrils chemically and/or by absorption of polymers, for example.

A further advantage of the use of MFC is the improved printability, including digital printing possibilities. In addition or as an alternative, MFC may reduce cost by reducing the weight or grammage by increasing the amount of fillers. This may also enhance the optical properties.

It will be understood that combinations of MFC and/or PBS and/or biodegradable aliphatic polyesters may further improve the mentioned effects and advantages. Also, combinations with conventional polymer films, for example by coating MFC, PBS and/or a biodegradable aliphatic polyester thereon, may provide a product with the advantages of both types of material.

In a further preferred embodiment of the invention the method further comprises the step of providing a finishing layer to the moulded product.

Such finishing layer may involve coating and/or printing, optionally including in-mould labelling and/or coating. This further improves the efficiency of the overall manufacturing process.

In a further preferred embodiment of the invention the fluff pulp material and/or barrier material is wetted when being provided to the mould and/or when being already provided in the mould.

Wetting the (luff pulp and/or barrier material during the manufacturing has the surprising effect that more and/or stronger hydrogen bonds are formed. This coniributes to the strength and stability of the end-product.

The invention further relates to 3-dimensional shaped product from a fluff pulp material, wherein the product comprising an amount of fluff pulp material and a barrier layer that comprises a biodegradable polymer layer and/or cellulose-based layer.

Such product provides the same effects and advantages as described in relation to the 3- dimensional shaped product, such as a food packaging unit. Such a 3-dimensional shaped product from a fluff pulp material may relate to packaging units for fruits and eggs, sip lids, covers, and inlay trays, for example. Preferably, the 3-dimensional product is shaped in accordance with its intended use. For example, in case of a food packaging unit, it may comprise a compartment capable of receiving or carrying a food product. For example, a food receiving compartment may relate to a compartment capable of holding a food product, such as eggs, tomatoes, kiwis, or a container for holding a beverage.

Providing the product with a barrier layer in an embodiment described earlier in relation to the method of the invention achieves or at least improves the barrier properties as discussed earlier.

As mentioned in relation to a method in an embodiment of the invention properties of the packaging unit can be further improved by providing a barrier layer, optionally encapsulated between other layers to further enhance the barrier properties.

As a further effect the product of the invention may comprise one or more additives or agents, such as a biodegradable polymer. This enables a specific design of the productcharacteristics and properties according to customer’s specifications or needs taking into account the specific product. Preferably, the one or more further agents comprise a biodegradable aliphatic polyester.

Further advantages, features and details of the invention are elucidated on the basis of preferred embodiments thereof, wherein reference is made to the accompanying drawings, in which: - Figure IA and 1B shows a packaging unit according to the invention; ~ Figure 1C, 1D and 1E show details of a wall of a product according to the invention in different embodiments with different layers; ~ Figure 1F shows an inlay tray according to the invention; — Figure 2A and 2B shows an alternative packaging unit according to the invention; ~ Figure 3 shows an example of a further alternative food packaging product according to the present invention; — Figure 4A and 4B shows an example of a further alternative food packaging product according to the present invention; ~ Figure 5A and 5B shows further packaging units for eggs according to the present invention; and — Figure 6 shows a summary of a schematic overview of the manufacturing method of the invention.

3-Dimensionally shaped packaging unit 1022 (figure 1A) shows an embodiment of a food receiving container having bottom part 1024 and side walls 1026 defining opening 1028. Packaging unit 1022 has length L, width W and height H. On the inside of container 1022 there is provided laminate layer 1030, optionally comprising a print. In the illustrated embodiment laminate layer 1030 is provided on the inside of packaging unit 1022 and extends from bottom part 1024 up to contour or edge 1032. Contour or edge 1032 is provided a small distance from the upper side of edge 1034. This distance is preferably in the range of 1 to 12 mm. Edge 1034 (figure 1B) is provided with width WI that defines contact surface 1036 for connecting to a liner or seal. In the illustrated embodiment this liner or seal is connected directly to the moulded pulp material, optionally with an adhesive, in stead of being connected to laminate layer 1030. Width W1 is in the illustrated embodiment in the range of 1 to 15 mm, preferably in the range of 2 to 5 mm.

Packaging unit 1022 (figure 1A) comprises first denesting elements 1038 and second denesting elements 1040. In the illustrated embodiment denesting elements 1038, 100 enable denesting of a stack of packaging units 1022. Denesting elements 1038, 1040 are designed asymmetrically. It will be understood that alternative denesting elements can also be envisaged in accordance with the present invention as alternatives or in combination. These alternative denesting elements can be designed asymmetrically or symmetrically. Asymmetrical denestingelements enable denesting with packaging units 1022 in one orientation and disable or at least render denesting more difficult in another orientation. Denesting elements 1038, 1040 have as an additional advantage that these elements do not significantly change the size of contact surface 1036 and/or the internal volume of packaging unit 1022. In the illustrated embodiment, denesting elements 1038, 1040 are provided at or adjacent edge 1034. This prevents the provision of marks, edges, protrusions, nocks and the like on or close to bottom part 1024. Such irregularities on or close to bottom part 1024 hinders cleaning or emptying packaging unit 1022.

Bottom 1024 and wall 1026 may comprise different layers.

In one embodiment there is provided first layer 1042 (figure 1C) from a fluff pulp material and a second layer 1044 from a barrier material, such as a biodegradable polymer and/or cellulose-based layer, optionally comprising an amount of another additive, such as PVOH or HAVOH. Optionally, both layers 1042, 1044 comprise an amount of PLA and/or another suitable material.

In another embodiment there are provided first and second layers 1046 a, b (figure 1D) from a fluff pulp material and an intermediate layer 1048 from a barrier material, such as a biodegradable polymer and/or cellulose, optionally comprising an amount of another additive such as HAVOH (highly amorphous vinyl alcohol polymer that is biodegradable and compostable). Optionally, one or more of the layers 1046 a,b comprise an amount of PLA and/or another suitable material.

Barrier layer 1044, 1048 (Figure 1E) may comprise first outer layer 1050, first adherence layer 1052, (central) polymer layer 1054, second adherence layer 1056 and second outer layer

1058. In this embodiment, the adherence layers 1052, 1056 comprise a mixture of PLA and PBS, outer layers 1050, 1058 comprise a biopolyester such as PHBH and optionally a mixture of biodegradable polymers, and the (central) biodegradable polymer layer preferably comprises a biodegradable vinyl alcohol polymer, such as HAVOH. It will be understood that other combinations and mixtures can also be envisaged in accordance with the present invention.

Further examples of products will be illustrated and/or described. It will be understood that these examples may all include a number of layers in the wall and/or bottom and/or cover parts.

Product 1 (Figure 1E) relates to an inlay tray for a mobile phone. Product 1 comprises outer edge 3 and recess 5 that is adapted to the size of the specific type of mobile phone. Product 1 is manufactured from a fluff pulp material and preferably comprises a biodegradable polymer.

Product 2 relates to a packaging unit (figure 2A and 2B) that in use carries or holds eggs and comprises cover part 4 and bottom part 6. Bottom part 6 is provided with back surface 8, sides 10 and front surface 12, and bottom surface 14. Cover part 4 is provided with back surface 16, sidesurfaces 18, front surface 20 and top surface 22. In the illustrated embodiment transition 24 is provided between top surface 22 and back and front surfaces 16, 20. In the illustrated embodiment, top surface 22 of cover part 4 is provided with groove 26 comprising a number of openings 28. Openings 28 are defined by two adjacent arch-shaped edges 30, 32 having a larger thickness as compared to the average thickness of cover part 4. Side surfaces 18 of cover part 4 are provided with denest nocks or denest elements 34. In the illustrated embodiment, bottom part 6 is provided with similar elements 36 mirroring denest elements 34. Hinge 38 connects back surface 16 of cover part 4 with back surface 8 of bottom part 6. Lock 40 comprises nose-shaped lock element 42 that is connected to flap 44 of bottom part 6. Cover part 4 is provided with openings 46 that capture lock elements 42 therewith defining lock 40.

In the illustrated embodiment, bottom part 6 is provided with a number of product receiving compartments 48, cones 50 and separating walls 52. Cone 50 extends from the bottom of bottom part 6 in an upward direction. Cover part 4 comprises cone support 54. Inner surface 58 of packaging unit 2 comprises PBS material, optionally as film layer or alternatively blended and/or integrated with the fibres of the moulded pulp material.

In the illustrated embodiment, packaging unit 2 comprises twelve product receiving compartments 48 that are provided in two rows of six compartments 48. Individual compartments 48 are separated from each other by walls 52 and cones 50. 1t will be understood that other configurations can also be envisage in accordance to the invention.

Packaging unit 2 may also be configured to receive other products, such as tomatoes, kiwis. The improved barrier properties may improve shelf life of these products.

It will be understood that other types of food packaging units can also be envisaged in accordance with the present invention. As a further example, bottle divider 101 (Figure 3) is illustrated. Also, bottle divider 102 may comprise a film layer of PBS and/or may comprise an amount of PBS that is blended into the moulded pulp. It will be understood that other barrier layers can also be applied in accordance with the present invention to bottle divider 102.

A further example in accordance with the present invention is cover 202 (Figure 4A), for example for an ice cup. Another example of a packaging unit according to the invention is sip lid 302 (Figure 4B). Cover 202 and sip lid 302 comprise a film layer of PBS and/or other suitable biodegradable polymer and/or may comprise an amount of PBS and/or other suitable biodegradable polymer that is blended into the moulded pulp. This renders cover 202 and sip lid 302 water or liquid repellent. One of the further advantages of the use of PBS and/or other suitable biodegradable polymer is the reduction or prevention of the liquid entering or migrating into the sip lid material during use. Another advantage is the constancy of size or dimensional stability. In this specific case this prevents sip lid 302 loosening from a cup or beaker for hot beverages such as coffee, tea or soup, or cold beverages such as carbonated drinks, and cup 202 from loosening froman ice cup, for example. It will be understood that such lids 302 can also be applied to other food containers. For example, lids 302 can be applied to containers for milkshakes, for example. Further details and examples of lids 302 are disclosed in WO 2010/064899, including embodiments with specific flanges and notches.

Sip lid 302 is preferably coated with a PBS and/or other suitable biodegradable polymer liner. As mentioned, sip lids 302 can be used for cups and milkshakes. Also, sip lids can be applied to so-called ready meal trays (for example for pizza, wraps, fish, meat, lobster, pasta, ...) and act as a (digital) printable and barrier seal, for example. The improved barrier properties may improve shelf life of these products.

It will be understood that other designs for packaging units in accordance with the invention can be envisaged. For example, containers 402, 502 {Figure 5A and 5B) illustrate different designs for egg cartons capable of holding eggs P. The improved barrier properties may improve shelf life of these products.

Other examples of food packaging products may relate to cup carriers, cups, plates and other table ware etc.

When manufacturing 602 a 3-dimensional shaped product 1, 2, 102, 202, 302, 402, 502, 1022 (Figure 6) a fluff pulp material is prepared in preparation step 604. Optionally, an amount of PBS and/or PLA and/or another suitable biodegradable polymer is blended or mixed into the pulp material in mixing step 606. Further treatments involve defibrization and/or shredding 608, compacting 610, providing the pulp to the mould 612. Optionally, this also comprises providing barrier material to the mould, preferably as a separate (film) layer, optionally comprising multiple layers. Optionally the manufacturing may also involve punching, moulding 614, optionally performing heat treatment 616, and releasing the product 618 to provide 3-dimensional shaped product 1, 2, 102, 202, 302, 402, 502, 1022. Optionally, a barrier layer is provided after an intermediate product is released from the mould. This may involve laminating a cellulose-based layer and/or spray coating a biofilm. Optionally, the barrier layer is co-extruded and deep-drawn with the (luff pulp material in the desired shape. In the illustrated embodiment a recycle step is shown. In one of the presently preferred embodiments of the invention, the pulp that is provided to the mould in step 612 has a dry matter content above 10 wt%. The length of the cellulose fibers is preferably chosen in relation to the intended use of the 3-dimensional product. Process conditions in the manufacturing are preferably chosen in relation to pulp composition, preferably taken the type and amount of additives into account.

It will be understood that this schematic overview of a manufacturing method of the invention is exemplary and different steps can be included, such as adding further agents and/or additives, providing a biodegradable polymer as a separate layer. Such separate layer may come into contact with a food product. Optionally, also several post-moulding operations may optionallybe performed in relation to unit 1, 2, 102, 202, 302, 402, 502, 1022 optionally including, but not limited to, labelling including in-mould labelling, marking including printing and digital printing, testing. In several of the preferred embodiments, the compostable biofilm is at least arranged on the food contact area of the product containing part of the packaging unit. In preferred embodiments this film is capable of being used in a microwave or oven as a so-called ovenable film. Preferably, the biofilm is capable of withstanding temperatures up to 170 °C, 190 °C, or even higher. This biofilm preferably comprises an amount of PBS and/or MFC and/or other suitable biodegradable aliphatic polyester that may comprise an amount of one or more of PBS, PHB, PHBH, PHA, PCL, PLA, PGA, and PHBV. Especially a combination of a compostable packaging IO unit involving in-mould drying further improves the sustainability as compared to conventional packaging units. The (digital) printable properties enable printing of packaging and/or food characteristics/information. This may obviate the use of separate sleeves, for example. In addition, it enables the application of prints, for example a fish&chips (newspaper) print on the packaging unit.

The present invention is by no means limited to the above described preferred embodiments thereof. The rights sought are defined by the following claims, within the scope of which many modifications can be envisaged.

Clauses

1. Method for manufacturing a 3-dimensional shaped product from a fluff pulp material, the method comprising: — providing a fluff pulp material; — providing an air-laid flow of fluff pulp material to a 3-dimensional shaped mould; — forming the product in the mould; and — releasing the layered 3-dimensional shaped product from the mould, wherein a barrier layer is provided that comprises a biodegradable polymer layer and/or a cellulose-based layer.

2. Method according to clause 1, wherein the biodegradable polymer comprising an aliphatic polyester.

3. Method according to clause 2, wherein the aliphatic polyester comprising one or more of PBS, PHB, PHBH. PHA, PCL, PLA, PGA, and PHBV.

4. Method according to clause 1, 2 or 3, wherein the biodegradable polymer layer comprises a biodegradable and compostable vinyl alcohol polymer, preferably a highly amorphous vinyl alcohol polymer.

5. Method according to one of the foregoing clauses, wherein the barrier layer comprises a first outer layer on a first side of the biodegradable polymer layer, and a second outer layer on a second side of the biodegradable polymer layer opposite to the first side, wherein the first and second outer layers comprise one or more biodegradable polymers.

6. Method according to clause 5, wherein the first and second outer layer are connected or attached to the biodegradable polymer layer with a respective first and second adherence layer of a biodegradable material.

7. Method according to one of the foregoing clauses, wherein providing the cellulose- based layer comprises the step of providing a cellulose-based laminate layer.

8. Method according to clause 7, further comprising the step of melting and/or fusing the cellulose-based laminate layer with the biodegradable aliphatic polyester.

9. Method according to any of the foregoing clauses, wherein the barrier layer is provided to the 3-dimensional shaped mould.

10. Method according to any of the foregoing clauses, wherein the barrier layer is provided as an intermediate layer between two layers of fluff pulp material.

11. Method according to any of the foregoing clauses, wherein the barrier layer is provided on one side of the product.

12. Method according to any of the foregoing clauses, wherein the barrier layer comprises polyvinyl alcohol and/or ethylene vinyl! alcohol.

13. Method according to any of the foregoing clauses, wherein providing the fluff pulp material comprises defibrizing raw material.

14. Method according to any of the foregoing clauses, further comprising the step of compacting the fluff pulp material before providing it to the mould.

15. Method according to any of the foregoing clauses, wherein the step of providing an air-laid flow of fluff pulp material comprises providing a blanket-shaped flow to the mould, and wherein forming the product in the mould comprises the step of punching the product out of the blanket-shaped flow and providing it to the mould.

16. Method according to clause 15, further comprising the step of feeding the remaining material to the providing step of the fluff pulp material.

17. Method according to any of the foregoing clauses, further comprising the step of mixing the fluff pulp material with pulp material originating from recycled paper material.

18. Method according to any of the foregoing clauses, further comprising the step of providing one or more additives to the fluff pulp material and/or the barrier layer, wherein the one or more additives comprises a biodegradable polymer.

19. Method according to clause 18, wherein the biodegradable polymer comprises a biodegradable aliphatic polyester, preferably one or more of PBS, PHB, PHBH, PHA, PCL, PLA, PGA and PHBV.

20. Method according to any of the foregoing clauses, further comprising the step of providing a finishing layer to the moulded product.

21. Method according to any of the foregoing clauses, further comprising the step of wetting the fluff pulp material and/or barrier material when being provided to the mould and/or when being already provided in the mould.

22. 3-dimensional shaped product from a fluff pulp material, the product comprising a layer from an amount of fluff pulp material and a barrier layer that comprises a biodegradable polymer layer and/or cellulose based layer.

23. Product according to clause 22, wherein the material of the fluff pulp material and/or the barrier layer further comprises a biodegradable aliphatic polyester, preferably one or more of PBS, PHB, PHBH, PHA, PCL, PLA, PGA and PHBV.

24. Product according to clause 22 or 23, wherein the product is one or more of the following: packaging units for fruits and eggs, sip lids, covers, and inlay trays.

Claims

Conclusions

Method for manufacturing a 3-dimensionally shaped product from a fluff pulp material, the method comprising: - providing a fluff pulp material; - providing an air-laid flow of fluff pulp material to a 3-dimensional mold; - forming the product in the mold; and - removing the 3-dimensionally shaped product from the mold, in which a barrier layer is provided comprising a biodegradable polymer layer and / or a cellulose-based layer.

The method of claim 1, wherein the biodegradable polymer comprises an aliphatic polyester.

The method of claim 2, wherein the biodegradable aliphatic polyester is one or more of PBS, PHB, PHBH, PHA, PCL. PLA, PGA. and includes PHBV.

The method of claim 1, 2 or 3, wherein the biodegradable polymer layer comprises a biodegradable and compostable vinyl alcohol polymer, preferably a high amorphous vinyl alcohol polymer.

A method according to any preceding claim, wherein the barrier layer comprises a first outer layer on a first side of the biodegradable polymer layer, and a second outer layer on a second opposite side of the biodegradable polymer layer, wherein the first and second outer layers comprise one or more biodegradable polymers.

The method of claim 5, wherein the first and second outer layers are bonded to, or adhered to, the biodegradable polymer layer with a respective first and second adhesive layer of a biodegradable material.

A method according to any preceding claim, wherein providing the cellulose-based layer comprises the step of providing a cellulose-based laminating layer.

The method of claim 7, further comprising the step of melting and / or joining the cellulose-based laminating layer with the biodegradable aliphatic polyester.

A method according to any preceding claim, wherein the barrier layer is provided to the 3-dimensionally molded mold.

A method according to any preceding claim, wherein the barrier layer is provided as an intermediate layer between two layers of fluff pulp material.

A method according to any preceding claim, wherein the barrier layer is provided on one side of the product.

The method according to any of the preceding claims, wherein the barrier layer comprises polyvinyl alcohol and / or ethylene-vinyl alcohol.

A method according to any of the preceding claims, wherein providing the fluff pulp material comprises fiberizing the starting material.

The method of any of the preceding claims, further comprising the step of compressing the fluff pulp material prior to providing it to the mold.

A method according to any preceding claim, wherein the step of providing an air-laid flow of fluff pulp material comprises providing a blanket flow to the mold, and wherein forming the product in the mold is the step of punching the product from the blanket stream and providing it to the mold.

The method of claim 15, further comprising the step of supplying the residual material to the step of providing the fluff pulp material.

The method of any of the preceding claims, further comprising the step of mixing the fluff pulp material with pulp material from recycled paper material.

The method of any of the preceding claims, further comprising the step of providing one or more additives to the fluff pulp material, wherein the one or more additives comprise a biodegradable polymer,

The method of claim 18, wherein the biodegradable polymer comprises a biodegradable aliphatic polyester, preferably one or more of PBS, PHB, PHBH, PHA, PCL, PLA, PGA, and PHBV.

The method of any one of the preceding claims, further comprising the step of 10 providing a finish coat to the formed product.

A method according to any preceding claim, further comprising the step of wetting the fluff pulp material and / or barrier material when the material is provided to the mold and / or if the material is already present in the mold.

22. 3-dimensionally shaped product from a fluff pulp material, comprising an amount of fluff pulp material and a barrier layer comprising a biodegradable polymer layer and / or a cellulose-based layer.

The three-dimensionally shaped product of claim 22, wherein the material further comprises a biodegradable aliphatic polyester, preferably one or more of PBS, PHB, PHBH, PHA, PCL, PLA, PGA, and PHBV.

A three-dimensionally shaped product according to claim 22 or 23, wherein the product is one of: packaging units for fruit and eggs, drinking lid, lids, and inlays.