Enhanced molded fiber capsules for food and beverage preparation

Abstract

The invention relates to a packaging article (1) comprising a three-dimensional body (2) made of a rigid or semi-rigid moulded fibrous pulp, said body forming compartments for enclosing the product and being adapted to be closed by closing means, characterised in that said body (2) further comprises a reinforcing mesh (7) at least partially embedded in a block of fibrous pulp, said reinforcing mesh (7) being made of a rigid or semi-rigid moulded fibrous pulp. The web (7) comprises a fiber selected from the group consisting of natural plant fibers, animal fibers, biopolymer synthetic fibers or a combination thereof, the fiber being impregnated with a dried water-soluble biopolymer, a dried water-soluble compostable polymer, a dried starch-based solution or a combination thereof, or the fiber being impregnated with a solidified polypeptide.

Description

Technical Field

[0001] The present invention relates to a capsule for beverage preparation, which can be recycled in a paper recycling stream and includes an outer body made of compressed fiber pulp, the wall of which is reinforced to withstand high internal pressure. Background Art

[0002] Packaging articles, especially those for food and beverages, need to achieve various purposes. In addition to storing their contents, they also need to be mechanically resistant, due to the fact that during manufacturing, shaping, and / or filling, they may undergo processes that subject their constituent materials to high mechanical stresses. Then again, during transportation, storage, and / or during use, high mechanical stress conditions may also apply, which can compromise the integrity of the said packaging articles.

[0003] Capsules and pods for beverage preparation in beverage preparation machines are an example of such packaging articles that are especially subject to high mechanical stresses, especially during use. They are a convenient and clean method of consuming beverages. In the following description, the general term "capsule" will be used, and the general term "capsule" encompasses disposable packages for preparing beverages for human consumption by insertion into a beverage preparation machine, which is adapted to inject a fluid (in principle, hot water) into the package to mix with the ingredients contained therein. Examples of such beverage packages are not limited to rigid capsules, but also include rigid, semi-rigid, or flexible pods, powder packets, various types of cartridges, and even bag-like containers.

[0004] Typically, such capsules are made of plastics such as polyolefins or biodegradable plastics, which are usually injection-molded or thermoformed to obtain a cup-shaped body filled with ingredients, and then sealed with a diaphragm in an airtight and moisture-proof manner to close the capsule.

[0005] As mentioned above, in recent times, there has been an increasing awareness of the environmental impact of packaging plastics, and there is a need for new packaging solutions that are biodegradable or recyclable after use, and in particular, that enable used packaging to be composted or recycled in a recycling stream suitable for paper or cardboard ("paper recycling stream").

[0006] Therefore, recently, beverage preparations made of cellulose fiber pulp (or "pulp" or "fibers") have been developed, which are molded to form a rigid or semi-rigid capsule cup-shaped body that defines a compartment for containing beverage precursor ingredients such as roasted and ground coffee. The cup-shaped body is closed by attaching (e.g., by sealing) a wall such as a diaphragm or film thereto.

[0007] To ensure the freshness of the beverage precursor ingredients over the life of the capsule, especially during storage until use, it is necessary to incorporate oxygen and moisture barrier materials into the fiber slurry (and the closing diaphragm). The barrier material typically takes the form of a so-called "barrier liner", which is a multi-layer film adhered to the inner surface of the slurry body (i.e., the surface facing the ingredients). Adhering the liner to the slurry is accomplished by thermoforming both in a mold. Not all of the layers in the barrier liner itself confer barrier properties: some of them serve as adhesion promoters between other barrier layers and structural layers of the liner. Such an adhesion promoting layer is the so-called "tie layer".

[0008] During beverage preparation, the capsule is inserted into the brewing chamber of a beverage preparation machine. The machine includes a water injection device, such as a set of blades designed to pierce the thickness of the capsule body and inject water therein under pressure. The water is mixed with the ingredients that produce the beverage. A high internal water pressure is necessary to achieve proper extraction of flavor substances, proteins, and other components from the precursor ingredients contained in the capsule and allows for the dispensing of a high-quality product to the consumer. In the case of coffee, it is necessary for the water pressure inside the capsule to reach a pressure of several bars to effect proper extraction of coffee aromatic compounds and proteins, thereby producing a high-quality coffee crema on top of the coffee. The pressure inside a high-quality capsule for preparing high-quality coffee can reach up to 8 bar (pressure relative to the ambient atmospheric pressure outside the capsule), or even up to 15 bar.

[0009] As described above, beverage preparation using slurry-based capsules is a very promising way to reduce the environmental footprint of packaging. However, technical deficiencies have emerged during the use of capsules within beverage preparation machines.

[0010] By design, the brewing chamber (or "capsule holder") of a beverage preparation machine is slightly larger than the outer boundary of the capsule to allow for easy removal of the capsule from the chamber after use.

[0011] Furthermore, during the use (or "extraction") phase, the beverage capsule is exposed to high stresses due to the high temperature of the water injected into the beverage capsule (the extraction water is typically heated to a temperature between 80 °C and 95 °C), or due to the extraction principle to an internal pressure of the water injected into the beverage capsule of up to 14 bar or sometimes even 15 bar, or to mechanical constraints on the capsule wall (such as in the case of the so-called "Vertuoline" Nespresso system, where the capsule rotates at a very high speed during extraction, which generates between 400 N / cm 2 and 700 N / cm 2 in the range, typically about 500 N / cm 2centrifugal force). Depending on the type of beverage preparation machine and capsule, there may also be a combination of two or more of the above constraints on the material.

[0012] In prior art capsules made of thermoplastic polymers such as, for example, polypropylene (PP), the material is sufficiently elastic and flexible such that when the internal pressure in the capsule compartment increases, the material can expand to conform to the brewing chamber profile. Alternatively, in some cases where the capsule body is made of a metal such as aluminum, the metal is strong enough to withstand mechanical forces (shearing forces or internal pressure, which may be combined with the high temperature of the water).

[0013] However, it has been found that, unlike polypropylene or aluminum, the molded slurry wall structure is a very soft material and, for example, has very low elongation properties that simply cannot compensate for the gap between the capsule body and the capsule holder. As a result, the molded slurry capsule bursts when the internal pressure inside the capsule increases or generally when high mechanical forces are applied to the capsule because the capsule wall is not properly held and supported by the capsule holder or the brewing chamber during extraction. Thus, the molded slurry capsule body expands within the brewing chamber (or capsule holder), and the slurry material rapidly reaches a tensile state that exceeds its mechanical resistance limit.

[0014] Of course, bursting of the capsule is highly undesirable because of the poor quality of the beverage obtained therefrom, but also because of the mess and even safety challenges that such bursting may trigger.

[0015] Accordingly, a main object of the present invention is to provide a technical solution to the above challenges, the technical solution being a packaging article made of molded slurry, such as a beverage capsule, the packaging article having high mechanical resistance, and wherein the packaging article is preferably recyclable and / or industrially or domestically compostable. Summary of the Invention

[0016] The present invention achieves the above object with a packaging article comprising a three-dimensional body made of rigid or semi-rigid molded fiber slurry, said body forming a compartment for enclosing a product and being adapted to be closed by a closing device, characterized in that said body further comprises a reinforcing rigid mesh at least partially embedded in a mass of the fiber slurry, said mesh comprising fibers selected from the following list: natural plant fibers, animal fibers, biopolymer synthetic fibers or combinations thereof, said fibers being impregnated with a dry water-soluble biopolymer, a dry water-soluble compostable polymer, a dry starch-based solution or combinations thereof, or said fibers being impregnated with a cured polypeptide.

[0017] Furthermore, if any biopolymer is used in the context of the present invention, a preferred biopolymer suitable for the present invention is a home-compostable polymer. Home-compostability is defined at the regional or national level and is generally based on the international standard EN 13432. Materials or products that meet these standards can be identified by a conformity mark stating their home-compostability. Some examples of home-compostability certifications at the national level include, but are not limited to, the following. The certification body TüV AUSTRIA BELGIUM offers such a home-compostability certification scheme, and DIN CERTCO offers home-compostability certification according to the Australian standard AS 5810. Italy has the national standard UNI 11183:2006 for composting at ambient temperature. In November 2015, the French standard "NF T51-800 Plastics - Specifications for plastics suitable for home composting" was introduced. This standard is covered in the DIN CERTCO scheme.

[0018] In a preferred embodiment of the present invention, the packaged article further comprises a multi-layer film liner attached to the inner surface of the fibrous slurry body.

[0019] Advantageously, the liner may comprise, from the outside to the inside:

[0020] (i) The outermost polymer layer, which comprises a biodegradable polymer selected from the following list: polybutylene succinate (PBSA / bioPBS), polybutylene adipate terephthalate (PBAT), starch, cellulose derivatives, polylactic acid (PLA), polyhydroxyalkanoates (PHA) or a combination thereof. The outermost layer has a thickness between 10 μm and 100 μm, and the first layer has an elongation at break between 10% and 800%

[0021] and a melt flow rate (MFR) between 2 and 4 when measured at 150 °C under a pressure of 2.16 kg for 10 minutes, and the first layer has a melting point temperature below 80 °C,

[0022] (ii) A first bonding layer, which comprises a biodegradable modified or functionalized polyolefin, has a melting point temperature between 180 °C and 230 °C and a thickness between 1 μm and 12 μm,

[0023] (iii) A barrier layer, which comprises a polymer selected from the following list: butylene glycol vinyl alcohol copolymer (BVOH), polyvinyl alcohol (PVOH) or a combination thereof, and has a melting point temperature between 180 °C and 230 °C and a thickness between 1 μm and 15 μm,

[0024] (iv) A second bonding layer, the second bonding layer comprising a biodegradable modified or functionalized polyolefin, having a melting temperature between 180 °C and 230 °C and a thickness between 1 μm and 10 μm,

[0025] (v) An innermost polymer layer, the innermost polymer layer comprising a biodegradable polymer selected from the following list: polybutylene succinate (PBSA), polybutylene adipate terephthalate (PBAT), starch, cellulose derivatives, polylactic acid (PLA), polyhydroxyalkanoates (PHA), or combinations thereof, the first layer having a thickness between 10 μm and 100 μm, and the innermost layer having an elongation at break between 10% and 1000%, a melt flow rate (MFR) between 4 and 10 when measured at 190 °C under a pressure of 2.16 kg for 10 minutes, and the first layer having a melting temperature between 110 °C and 180 °C.

[0026] In an alternative embodiment, the liner comprises, from outside to inside:

[0027] (i) An outermost organic adhesive layer for attaching the liner to the molded fiber slurry, the adhesive layer comprising a biodegradable polymer selected from the following list: polybutylene succinate (PBSA / bioPBS), polybutylene adipate terephthalate (PBAT), starch, cellulose derivatives, polylactic acid (PLA), polyhydroxyalkanoates (PHA), or combinations thereof, the outermost layer having a thickness between 10 μm and 100 μm, and the first layer having an elongation at break between 10% and 800%, a melt flow rate (MFR) between 2 and 4 when measured at 150 °C under a pressure of 2.16 kg for 10 minutes, and the first layer having a melting temperature below 80 °C,

[0028] (ii) An organic intermediate barrier layer comprising a butylene glycol vinyl alcohol copolymer (BVOH) grafted with maleic anhydride and having a melting temperature between 180 °C and 230 °C and a thickness between 1 μm and 20 μm,

[0029] (iii) The innermost organic structure layer, which comprises a biodegradable polymer selected from the following list: polybutylene succinate (PBSA), polybutylene adipate terephthalate (PBAT), starch, cellulose derivatives, polylactic acid (PLA), polyhydroxyalkanoates (PHA), or combinations thereof, wherein the first layer has a thickness between 10 μm and 100 μm, and the innermost layer has an elongation at break between 10% and 1000%, a melt flow rate (MFR) between 4 and 10 when measured at 190 °C under a pressure of 2.16 kg for 10 minutes, and the first layer has a melting point temperature between 110 °C and 180 °C.

[0030] In one embodiment of the present invention, the packaging article may be a primary packaging selected from the following list: tray, pouch, gusseted wrapper, tube, bag, box, brick, container, closure, or combinations thereof; alternatively, the packaging article of the present invention may be a secondary packaging for enclosing the primary packaging.

[0031] In another embodiment of the present invention, the packaging article is a capsule for beverage preparation, the capsule comprising a cup-shaped body and at least one closing diaphragm attached to the body, the body and the at least one diaphragm defining a closed ingredient compartment, the capsule being adapted to be pierced by a water injection device of a beverage preparation machine for injecting water into the compartment under pressure to prepare a beverage therein.

[0032] In such a capsule embodiment, the cup-shaped body preferably comprises a periphery to which the closing diaphragm is attached.

[0033] Furthermore, the closing diaphragm may advantageously be made of an extruded coated paper, a fiber spun coated paper, or a polymer film comprising a compatible polymer material.

[0034] Generally, the packaging article according to the present invention may be manufactured by injection molding, compression molding, extrusion molding, or thermoforming.

[0035] Importantly, the net used in the packaged article according to the invention is preferably made of vegetable or animal fibers, which include seed hairs such as cotton, or stem (or bast) fibers such as flax and hemp, leaf fibers such as sisal, husk fibers such as coconut, or hardwood fibers derived from the following trees: ash (Genus Fraxinus), beech (Genus Fagus), linden (Genus Tilia), birch (Genus Betula), black cherry (Genus Prunus), black walnut / grey walnut (Genus Juglans), cottonwood (Genus Populus), elm (Genus Ulmus), American hackberry (Genus Celtis), hickory (Genus Carya), holly (Genus Ilex), locust (Genus Robinia; Genus Gleditsia), magnolia (Genus Magnolia), maple (Genus Acer), oak (Genus Quercus), poplar (Genus Populus), alder (Genus Alnus), paulownia (Genus Paulownia), sassafras (Genus Sassafras), sweetgum (Genus Liquidambar), sycamore (Genus Platanus), tupelo (Genus Nyssa), willow (Genus Salix), tulip tree (Genus Liriodendron), eucalyptus, fungi, silk, wool or a combination thereof.

[0036] The product packaged in the packaged article is advantageously an edible product for human or animal consumption, in particular roasted and ground coffee, water-soluble ingredients for the preparation of beverages, soup powders, infant nutritional products, cocoa-based or milk-based compositions, fruit juice precursors or a combination thereof.

[0037] The length of the fibers of the body block suitable for manufacturing the packaged article according to the invention preferably ranges from 0.1 mm to 50 mm.

[0038] The diameter of the fibers of the reinforcing net suitable for manufacturing the packaging article according to the present invention preferably ranges from 5 μm to 30 μm, and their length preferably ranges from 0.5 cm to 50 cm. The tensile strength of the fiber slurry fibers preferably ranges from 1200 MPa to 2000 MPa, preferably from 1500 MPa to 1800 MPa.

[0039] Equally importantly, the preferred water-soluble biopolymer is a water-soluble compostable polymer selected from the following list: starch or hydroxypropyl cellulose (HPLC) or a combination thereof.

[0040] Alternatively, the polypeptide suitable for use in the packaging article according to the present invention may be at least one of a fibrous polypeptide or a globular polypeptide selected from the following list: collagen, ovalbumin, serum albumin, lactoglobulin or a hydrolyzed form thereof.

[0041] The present invention further relates to a method for manufacturing the packaging article as described above, the method successively comprising the following steps:

[0042] (i) Pre-cutting a plain woven fiber matrix into a predetermined shape,

[0043] (ii) Immersing the plain net into a water-soluble biopolymer, a water-soluble compostable polymer, a starch-based solution or a combination thereof, or into a polypeptide solution,

[0044] (iii) Shaping the plain net into a three-dimensional net preform and drying the water-soluble biopolymer, the water-soluble compostable polymer and / or the starch-based solution, or curing the polypeptide solution into a Maillard reaction to obtain a rigid net

[0045] (iv) Placing the net preform on the male forming part of a slurry forming mold to at least partially cover the male forming part with the net, the male forming part being equipped with a suction channel,

[0046] (v) Placing the male forming part into a slurry tank filled with fiber slurry and sucking the slurry fibers onto the surface of the male forming part such that the net is at least partially embedded in the wet mass of fibers,

[0047] (vi) Closing the mold by moving the male forming part into a female forming cavity, compressing the wet slurry into a three-dimensional article, and heating the mold to dry the wet slurry article,

[0048] (vii) Opening the mold and discharging the packaging article from the mold.

[0049] The so-called "lining" refers to a single-layer or multi-layer film obtained by extrusion-blowing, or extrusion-laminating, or casting-extrusion.

[0050] The so-called "fiber" refers to a material based on cellulose and / or animal fiber; within the framework of this specification, "slurry" or "fiber slurry" is a term equivalent to "fiber" and corresponds to the previously given definition. If the fiber slurry is made of cellulose material, the fiber slurry has a minimum proportion of cellulose fibers of 80%, preferably at least 95%; the remaining part contains non-cellulose binders or additives (such as AKD). To allow recyclability during the paper flow recycling process, the maximum amount of animal fiber cannot exceed 20% by volume of the total fiber volume, that is, the minimum amount of cellulose fiber is 80% by volume. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Additional features and advantages of the present invention are described below in the description of the currently preferred embodiments given with reference to the accompanying drawings, and these features and advantages will be apparent from this description, wherein:

[0052] Figure 1 is a schematic perspective view of a partially cut beverage preparation capsule according to a first embodiment of the present invention;

[0053] Figure 2 is according to Figure 1 a schematic cross-sectional view of the capsule, which depicts the incorporation of a reinforcing mesh according to the present invention into the structure of the capsule body;

[0054] Figure 3 is similar to Figure 2 a view of the capsule showing a second embodiment of the present invention;

[0055] Figure 4A 、 Figure 4B 、 Figure 4C 、 Figure 4D 、 Figure 4E 、 Figure 4F 、 Figure 4G and Figure 4H are schematic views of different steps of manufacturing a reinforced molded slurry cup-shaped body with an impregnated mesh according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0056] High-quality packaging articles, especially packaging articles used in high-quality beverage preparation systems such as beverage capsules, need to meet high-quality standards.

[0057] In particular, capsules that burst and / or leak during extraction (i.e., during the beverage preparation process) are unacceptable. The proposed invention aims to ensure that general packaging articles, and for example beverage preparation capsules, do not suffer from the aforementioned problems (such as bursting, leaking). For this reason, the present invention proposes to reinforce the body of the packaging article to meet mechanical resistance requirements.

[0058] In the example of a capsule (or pod or sachet) for beverage preparation in a beverage preparation machine, the capsule must withstand the pressure applied to its walls during extraction. This reinforcement comes from a natural fiber web added and at least partially embedded in the capsule wall. Such a web is designed to absorb the induced expansion forces applied to the capsule during its use.

[0059] As Figure 1 shown, a first embodiment of the present invention relates to a packaging article for a beverage preparation capsule 1. The beverage capsule 1 includes a cup-shaped capsule body 2, the inner surface of which is covered with an oxygen and barrier lining 3. As depicted in the enlarged partial view on the left-hand side of Figure 1 , the lining 3 includes three constituent layers. The capsule body 2 also includes a peripheral edge 4 around an opening, which is closed by a closing diaphragm 5 sealed to the edge 4. The capsule body enclosed by the diaphragm 5 defines a compartment 6 for accommodating precursor ingredients for beverage preparation, such as roasted and ground coffee ingredients (not shown).

[0060] As shown in the enlarged partial view, on the Figure 1 right-hand side, the cup-shaped capsule body 2 is made of molded fiber pulp. The overlapping arrangement of cellulose fibers is shown in the enlarged partial view of Figure 1 .

[0061] According to the principles of the present invention and as Figure 2 shown, the capsule body includes a reinforcement web 7. The web 7 is connected to the rest of the capsule body material and at least partially embedded in this rest, in particular in the inner surface of the fiber pulp wall, as shown in the enlarged partial view on the right-hand side of Figure 1 . Embedding the web at least partially in the mass of the fiber pulp allows the pulp material to be held during the application of forces to this pulp material.

[0062] In Figure 3 a similar but alternative embodiment of the present invention is depicted, which is a capsule for beverage preparation with a different structural design.

[0063] The reinforcement web 7 for mechanically reinforcing the packaging article according to the present invention is as follows.

[0064] The reinforcement mesh 7 is at least partially embedded in the mass of the fibrous slurry and preferably comprises natural plant fibres intricately forming the mesh matrix. The mesh may also comprise synthetic polymer fibres provided they are selected from biopolymers. The formation of the mesh matrix from individual fibres is itself a well-known process and will not be further discussed in this specification. The mesh is impregnated with a water-soluble biopolymer, a water-soluble compostable polymer, a starch-based solution or a combination thereof and formed into a shaped article having the shape of the part of the packaging article that will ultimately be reinforced (if the whole packaging article is to be reinforced, the shaped article may be the shape of the packaging article as a whole). The shape is very simple (i.e., a flat fabric-like article) or may be formed into a more complex three-dimensional article.

[0065] Impregnation of the mesh allows the delivery of thermosetting to the mesh, which causes the mesh to retain its shape once formed, for example, by a thermoforming process.

[0066] Preferably, the fibres used are flax or hemp. However, they may also be derived from another plant or animal fibre variety, such as those listed in the list provided above.

[0067] The beverage preparation capsule 1 according to the above-described embodiment is preferably manufactured in the following steps in sequence.

[0068] As Figure 4A shown, in the exemplary embodiment described therein, first the flat woven fibre matrix 7 is pre-cut into a predetermined shape, and then the flat mesh 7 is infiltrated into the polypeptide solution 8 ( Figure 4B ).

[0069] Then the flat mesh is placed into a mould and formed into a three-dimensional mesh preform 7 having a cup shape and a periphery 4. As Figure 4C shown, by heating the mould, the polypeptide solution impregnated into the mesh as a wet solution is dried and cured by the Maillard reaction in order to obtain a rigid three-dimensional cup-shaped mesh 7 impregnated with the dried and cured polypeptide ( Figure 4D "fibre preform" in). The rigidity of the reinforcement mesh 7 is imparted by the curing treatment of the polypeptide, which hardens the entire polypeptide matrix impregnating the mesh, thereby rendering the mesh itself a non-flexible matrix that retains the shape imparted by the forming step into the mould.

[0070] Alternatively, if a water-soluble biopolymer, a water-soluble compostable polymer and / or a starch-based solution is used instead of the polypeptide, only the solution is dried; in these cases, the Maillard reaction is not required as for the polypeptide, however in these cases drying is sufficient to harden and settle the mesh impregnated with such a polymer.

[0071] Then, as Figure 4EAs depicted, the impregnated, rigid and shaped mesh preform 7 is placed onto the male forming part 9 of the slurry forming mold to at least partially cover the male forming part with the mesh, the male forming part being equipped with a suction channel (not shown). By sucking air via the suction channel, the mesh 7 is held in place on the forming part 9, thereby creating a vacuum between the outer surface of the male forming part 9 and the mesh 7.

[0072] Then, the male forming part 9 covered with the mesh 7 is placed into a slurry tank filled with fiber slurry 10, as Figure 4F shown, and the slurry fibers are sucked from the slurry onto the surface of the male forming part 9 by the vacuum created at the surface of the mesh 7 and the male forming part 8 (the mesh is sufficiently permeable to allow the suction effect created by the suction channels of the male forming part 9 at the surface of the mesh). As a result, fibers accumulate on the surface of the mesh 7 and enter the mesh matrix until the mesh matrix is at least partially embedded in the wet mass of the fiber slurry.

[0073] Then, as Figure 4H shown, the mold is closed by moving the male forming part 9 into the female forming cavity 11, thereby compressing the mesh that is at least partially embedded in the wet fibers; the closed mold is heated to dry the wet slurry material until a dry cup-shaped capsule body 2 ( Figure 4H ) is obtained.

[0074] Finally, when the mold is reopened, the fiber capsule body 2 is discharged from the mold (not shown in the figure).

[0075] The same manufacturing steps can be used for other types of packaging articles other than beverage preparation capsules. The shape will change, but the manufacturing principle remains.

[0076] Molding fiber slurries are already known in the art and will not be described in more detail in this specification.

[0077] The mesh is designed to reinforce the capsule body and absorb the swelling loads generated by the extraction process, i.e., the internal fluid pressure due to water injected into the closed capsule or the centrifugal force applied to the capsule body when the capsule rotates within a beverage preparation machine for preparing coffee.

[0078] For such applications, the diameter and tensile strength (and, where possible, also the flexural modulus) of the fibers used to produce the mesh are key selection criteria. In one example, woven linen fibers are selected as the preferred fibers, which have the following preferred physical properties:

[0079] Fiber diameter [μm] 12 to 16 Tensile strength [MPa] 1500 to 1800 Fiber length (mm) 0.7 to 25

[0080] Flax fibers, such as cotton, are cellulose polymers, but their structure is more crystalline, making them stronger, more brittle, and harder. Flax is one of the strongest plant fibers in nature and one of the first plant fibers to be extracted, spun, and woven into textiles.

[0081] In this exemplary embodiment of the present invention, after the above manufacturing steps and once a hard and dry cup-shaped capsule body is obtained, a barrier lining film 3 is added to the fibrous slurry cup-shaped capsule body in order to provide the capsule with barrier properties against moisture and / or oxygen.

[0082] After forming the isolation lining film 3 according to the above manufacturing steps, the isolation lining film is provided as a flat sheet of polymeric material and placed over the opening of the slurry cup body 2 and thermoformed therein by a conventional thermoforming process.

[0083] Once the attachment process of the isolation lining 3 to the inner surface of the slurry cup body 2 is terminated, if necessary, the periphery 4 can be trimmed in order to obtain the correct edge diameter (the trimming operation is only performed if the edge molded only in the above manufacturing steps is not regular enough and has the correct dimensions).

[0084] After these steps, an empty reinforced slurry capsule 1 with barrier properties is obtained, as Figure 1 shown, the reinforced slurry capsule includes an opening through which coffee powder is filled. Then, the filled capsule is closed by sealing a diaphragm 5 to the edge 4 of the capsule according to a conventional sealing process. Then a fully formed, filled, and closed capsule made of reinforced fiber slurry is obtained.

[0085] For the upper and lower heat sources respectively, typical temperatures for thermoforming the lining into the molded slurry capsule body are in the range between 390 °C and 230 °C, or between 410 °C and 220 °C. The plug must fit properly to the capsule profile to ensure uniform lining distribution and deformation.

[0086] The finally thermoformed capsule has a uniformly distributed lining that exhibits good adhesion to the molded slurry surface. Typical barrier values of the capsule and lining structure vary between 0.001 cc / package / day / atmosphere and 0.01 cc / package / day / atmosphere, preferably below 0.009 cc / package / day / atmosphere, more preferably below 0.0033 cc / package / day / atmosphere.

[0087] The features of the present invention described above with respect to the beverage capsule also apply to another type of embodiment of the present invention, where the packaged article is not a beverage capsule but a secondary package, such as a molded pulp carton for containing a beverage, or a sachet for containing a product such as a powdered food. Of course, in each individual case, known manufacturing techniques can be employed to assemble the barrier liner onto the molded pulp component of the capsule.

[0088] It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. These changes and modifications can be made without departing from the essence and scope of the present invention and without diminishing the attendant advantages. Accordingly, such changes and modifications are intended to be covered by the appended claims.

Claims

1. A packaged article (1), said packaged article comprising a three-dimensional body (2) made of a rigid or semi-rigid molded fiber pulp, said body forming a compartment for enclosing a product and being adapted to be closed by a closing device (5), It is characterized in that , said body (2) further comprising a reinforcing rigid mesh (7) at least partially embedded in a mass of fiber pulp, said mesh (7) comprising fibers selected from the following list: natural plant fibers, animal fibers, biopolymer synthetic fibers or combinations thereof, said fibers being impregnated with a dry water-soluble biopolymer, a dry water-soluble compostable polymer, a dry starch-based solution or combinations thereof, or said fibers being impregnated with a cured polypeptide.

2. The packaging article (1) according to the preceding claim 1, wherein the packaging article further comprises a multi-layer film lining (3) attached to the inner surface of the fibrous pulp body (2).

3. The packaging article (1) according to any one of the preceding claims 1 or 2, wherein the lining (3) comprises, from the outside to the inside: (i) an outermost polymer layer, the outermost polymer layer comprising a biodegradable polymer selected from the list: polybutylene succinate (PBSA / bioPBS), polybutylene adipate terephthalate (PBAT), starch, cellulose derivatives, polylactic acid (PLA), polyhydroxyalkanoates (PHA) or a combination thereof, the outermost layer having a thickness between 10 μm and 100 μm, and the first layer having an elongation at break between 10% and 800%, a melt flow rate (MFR) between 2 and 4 when measured at 150 °C under a pressure of 2.16 kg for 10 minutes, and the first layer having a melting point temperature below 80 °C, (ii) a first bonding layer, the first bonding layer comprising a biodegradable modified or functionalized polyolefin, having a melting point temperature between 180 °C and 230 °C and a thickness between 1 μm and 12 μm, (iii) a barrier layer, the barrier layer comprising a polymer selected from the list: butylene glycol vinyl alcohol copolymer (BVOH), polyvinyl alcohol (PVOH) or a combination thereof, and having a melting point temperature between 180 °C and 230 °C and a thickness between 1 μm and 15 μm, (iv) a second bonding layer, the second bonding layer comprising a biodegradable modified or functionalized polyolefin, having a melting point temperature between 180 °C and 230 °C and a thickness between 1 μm and 10 μm and a thickness between, (v) an innermost polymer layer, the innermost polymer layer comprising a biodegradable polymer selected from the list: polybutylene succinate (PBSA), polybutylene adipate terephthalate (PBAT), starch, cellulose derivatives, polylactic acid (PLA), polyhydroxyalkanoates (PHA) or a combination thereof, the first layer having a thickness between 10 μm and 100 μm, and the innermost layer having an elongation at break between 10% and 1000%, a melt flow rate (MFR) between 4 and 10 when measured at 190 °C under a pressure of 2.16 kg for 10 minutes, and the first layer having a melting point temperature between 110 °C and 180 °C.

4. The packaging article (1) according to any one of the preceding claims 1 or 2, wherein the lining (3) comprises, from the outside to the inside: (i) an outermost organic adhesive layer for attaching the lining to the molded fibrous pulp, the adhesive layer comprising a biodegradable polymer selected from the list: polybutylene succinate (PBSA / bioPBS), polybutylene adipate terephthalate (PBAT), starch, cellulose derivatives, polylactic acid (PLA), polyhydroxyalkanoates (PHA) or a combination thereof, the outermost layer having a thickness between a thickness between 10 μm and 100 μm, and the first layer has an elongation at break between 10% and 800% and a melt flow rate (MFR) between 2 and 4 when measured at 150 °C under a pressure of 2.16 kg for 10 minutes, and the first layer has a melting point temperature below 80 °C, (ii) an organic intermediate barrier layer, the organic intermediate barrier layer comprising a butylene glycol vinyl alcohol copolymer (BVOH) grafted with maleic anhydride and having a melting point temperature between 180 °C and 230 °C and a thickness between 1 μm and 20 μm, (iii) an innermost organic structural layer, the innermost organic structural layer comprising a biodegradable polymer selected from the following list: polybutylene succinate (PBSA), polybutylene adipate terephthalate (PBAT), starch, cellulose derivatives, polylactic acid (PLA), polyhydroxyalkanoates (PHA) or combinations thereof, the first layer having a thickness between 10 μm and 100 μm, and the innermost layer having an elongation at break between 10% and 1000% and a melt flow rate (MFR) between 4 and 10 when measured at 190 °C under a pressure of 2.16 kg for 10 minutes, and the first layer having a melting point temperature between 110 °C and 180 °C.

5. The packaging article (1) according to any one of the preceding claims 1 to 4, the packaging article being a primary packaging selected from the following list: tray, sachet, gusseted wrapper, tube, bag, box, brick, container, closure or combinations thereof, the article being a secondary packaging for enclosing the primary packaging.

6. The packaging article (1) according to any one of the preceding claims 1 to 4, the packaging article being a capsule (1) for beverage preparation, the capsule comprising a cup-shaped body (2) having a periphery (4) and at least one closing diaphragm (5) attached to the periphery (4) of the body (2), the body (2) and the at least one diaphragm (5) defining a closed ingredient compartment (6), the capsule being adapted to be pierced by a water injection device of a beverage preparation machine for injecting water into the compartment under pressure to prepare a beverage in the compartment.

7. The packaging article (1) according to any one of the preceding claims 6, wherein the closing diaphragm (5) is made of an extruded coated paper, a fiber spun coated paper or a polymer film comprising a compatible polymer material.

8. The packaging article (1) according to any one of the preceding claims, the packaging article being manufactured by injection molding, compression molding, extrusion molding or thermoforming.

9. The packaged article (1) according to any one of the preceding claims, wherein the net is made of vegetable or animal fibers, said vegetable or animal fibers including seed hairs such as cotton, or stem (or bast) fibers such as flax and hemp, leaf fibers such as sisal, husk fibers such as coconut, or hardwood fibers derived from the following trees: ash (Genus Fraxinus), beech (Genus Fagus), linden (Genus Tilia), birch (Genus Betula), black cherry (Genus Prunus), black walnut / grey walnut (Genus Juglans), cottonwood (Genus Populus), elm (Genus Ulmus), American hackberry (Genus Celtis), hickory (Genus Carya), holly (Genus Ilex), locust tree (Genus Robinia; Genus Gleditsia), magnolia (Genus Magnolia), maple (Genus Acer), oak (Genus Quercus), poplar (Genus Populus), alder (Genus Alnus), paulownia (Genus Paulownia), sassafras (Genus Sassafras), sweetgum (Genus Liquidambar), sycamore (Genus Platanus), tupelo (Genus Nyssa), willow (Genus Salix), tulip tree (Genus Liriodendron), eucalyptus, mushroom, silk, wool or a combination thereof.

10. The packaged article (1) according to any one of the preceding claims, wherein the product packaged in the packaged article is an edible product for human or animal consumption, in particular roasted and ground coffee, water-soluble ingredients for preparing beverages, soup powder, infant nutritional products, cocoa-based or milk-based compositions, fruit juice precursors or a combination thereof.

11. The packaged article (1) according to any one of the preceding claims, wherein the tensile strength of the fiber pulp fibers is in the range of 1200 MPa to 2000 MPa, preferably 1500 MPa to 1800 MPa.

12. The packaged article (1) according to any one of claims 1 to 11 preceding, wherein the water-soluble biopolymer is a water-soluble compostable polymer selected from the following list: starch or hydroxypropyl cellulose (HPLC) or a combination thereof.

13. The packaged article (1) according to any one of the preceding claims 1 to 11, wherein the polypeptide is at least one of a fibrous polypeptide or a globular polypeptide selected from the following list: collagen, ovalbumin, serum albumin, lactoglobulin or a hydrolyzed form thereof.

14. A method for manufacturing a packaged article according to any one of the preceding claims 1 to 13, the method sequentially comprising the following steps: (i) pre-cutting a plain woven fiber matrix into a pre-determined shape, (ii) immersing the plain web into a water-soluble biopolymer, a water-soluble compostable polymer, a starch-based solution or a combination thereof, or into a polypeptide solution, (iii) forming the plain web into a three-dimensional web preform and drying the water-soluble biopolymer, the water-soluble compostable polymer and / or the starch-based solution, or curing the polypeptide solution into a Maillard reaction to obtain a rigid web, (iv) placing the web preform on the male forming part of a slurry forming mold to at least partially cover the male forming part with the web, the male forming part being equipped with a suction channel, (v) placing the male forming part into a slurry tank filled with a fiber slurry of fiber pulp and sucking the pulp fiber onto the surface of the male forming part such that the web is at least partially embedded in the wet mass of the cellulose fiber pulp, (vi) closing the mold by moving the male forming part into a female forming cavity, compressing the wet pulp into a three-dimensional article, and heating the mold to dry the wet pulp article, (vii) opening the mold and discharging the cellulose fiber packaged article from the mold.

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