ES2939589T3 - Capsule and device for preparing beverages and method for manufacturing a capsule - Google Patents

Abstract

The invention relates to a capsule for use in a beverage preparation device. The invention relates below to a method for manufacturing a capsule according to the invention. The invention also relates to an assembly of such a capsule and a device for preparing beverages. The invention further relates to the use of such a capsule according to the invention in a device for preparing beverages. (Automatic translation with Google Translate, without legal value)

Description

DESCRIPTION

Capsule and device for preparing beverages and method for manufacturing a capsule

The invention relates to a capsule for use in a beverage preparation device. The invention also relates to a closure element for use in a capsule according to the invention. The invention relates below to a method for manufacturing a capsule according to the invention. The invention also relates to an assembly of such a capsule and a device for preparing beverages.

Various capsules for use in a beverage preparation device are known in the prior art. A known capsule, as described for example in EP0512468, comprises an essentially frustoconical casing composed of a peripheral wall, an end entry side connected to the peripheral wall and a hooking edge laterally connected to the peripheral wall for holding the capsule in a capsule holder of the beverage preparation device. The engaging edge is connected to a perforated sheet that also forms the outlet side of the capsule. The casing is filled with a substance to be extracted, such as ground coffee beans. This known capsule can be placed in a device for preparing a drink. For this, the capsule is placed in a capsule holder, in which the capsule is then clamped, thus causing the inlet side of the capsule to be pierced. After this, warm water at a fairly high pressure (6-20 bar) is fed into the capsule holder and thus into the capsule through the inlet side, where the water must come into contact with the substance, thus forming the final drink. The build-up of pressure in the capsule should cause the foil to deform in such a way that the foil is pierced by the capsule holder, with the result that the beverage formed can escape from the capsule. The casing of the capsule described in said patent is made of aluminium. Although aluminum has quite favorable barrier properties, which allows you to preserve coffee for a long period of time, the processing of aluminum is quite problematic. In addition, the capsule must be disposed of after use, usually through standard waste disposal, which leads to considerable environmental contamination.

The document WO03/002423 describes a sealed flexible cartridge, designed to be extracted under pressure, which contains a substance for the preparation of a drink, made up of a first and a second sheet of circular, oval or polygonal shape that leave a space between them. for the substance and are welded together at their periphery, the first sheet being made of a material chosen from filter paper, a non-woven and semi-rigid material and the second sheet being made of a material chosen from filter paper, a non-woven and a material composite, in which the first sheet is such that it allows water to pass through at atmospheric pressure or when drilling with a drilling medium and the second sheet is such that it allows water to pass through only if an overpressure between 0.1 and 3 bar is applied reached during the extraction of said cartridge.

An object of the invention is to provide a fairly reliable functioning capsule for preparing beverages which, particularly after use, leads to reduced environmental pollution.

To this end, the invention thus provides a capsule of the type mentioned at the beginning, comprising: an essentially closed casing that is at least partially filled with a substance to be extracted and/or dissolved, such as ground coffee, to prepare a beverage, wherein the shell is defined by at least one peripheral wall, a bottom wall connected to the peripheral wall, and a laterally projecting engaging lip connected to the peripheral wall at a distance from the bottom wall to allow the capsule to be clamped in a shell of a beverage preparation device; and at least one essentially closed closure element configured to allow the beverage to flow from the capsule, said closure element being connected to the laterally protruding engaging edge to seal the substance in the capsule, wherein at least a portion of the closure element The closure is comprised of a laminated sheet, wherein the sheet is configured to tear as a result of pressure buildup in the capsule when water is injected into the capsule, said sheet comprising: at least one weakened layer, said weakened layer being provided with at least one weakened area, and said weakened layer preferably faces the substance retained by the casing, at least one carrier layer that is made at least partly of paper, in particular filter paper, and at least one oxygen barrier layer, said barrier layer is essentially impermeable to oxygen, and said oxygen barrier layer is positioned between said weakened layer and said carrier layer. The applied laminated foil used to hermetically seal the substance in the capsule allows for the application of more environmentally friendly materials compared to aluminum, leading to less environmental pollution. The foil applied to close the casing is essentially composed of paper and plastics (polymers), and preferably compostable paper and compostable plastics as will become clear later. Furthermore, the composition of the laminated sheet is such that, during use, the sheet will tear in a controlled manner to allow the beverage to flow from the cartridge in a controlled manner. Preferably, no metal layer is applied to the foil. The oxygen barrier layer allows to preserve, without oxygen or with little oxygen, the substance contained in the capsule, generally ground coffee, tea leaves, instant soup or powdered milk (chocolate) to prepare coffee, soup, tea or (chocolate) ) milk respectively. The oxygen barrier layer is generally configured in a completely closed (non-perforated) manner. Therefore, preferably, the closed oxygen barrier layer is not weakened so that it is possible to keep the oxygen barrier as favorable and uniform as possible. It is preferred in this case that the oxygen barrier has an essentially uniform layer thickness. The at least one weakened layer is commonly configured to carry, hold in place, and support the generally thinner oxygen barrier layer. The weakened layer is provided with at least one weakened area (preformed, during production of the sheet), with the result that the weakened layer itself is weakened. This weakened zone can be formed in various ways, as will be explained in more detail below. the weakened area it serves to allow the sheet to be torn in a simple and preferably controlled manner, when the capsule is used in a beverage-making device. If a weakened area is not formed, a (multilayer) plastic sheet tends to stretch rather than tear, which can make opening the capsule on the outlet side considerably more difficult or even impossible. Due to the (site-selective) weakened area in at least one carrier layer, the tearing of the film becomes considerably easier and, in general, the tearing behavior of the film will be essentially congruent with the tearing behavior of a classical film. aluminum based. The carrier layer which is composed at least partially, or preferably completely, of paper, in particular filter paper, is commonly configured to carry other layers of sheets. Commonly, this carrier layer is the thickest layer of all the sheet layers to provide the sheet with sufficient strength. Filter paper is a paper that is sufficiently porous to allow a drink to flow through it while preventing - eventual - solid (medium-sized) particles of the substance from flowing through it. Therefore, in addition to providing the sheet with greater firmness, the filter paper also has a filtering function. In addition, the filter paper prevents the sheet itself from being (excessively) stretched during use (at typical operating temperatures between 20 and 120 degrees Celsius) and thus prevents the sheet itself from being forced, due to the water pressure, to discharge openings of the capsule holder of a beverage preparation device, which ensures the correct functioning of both the capsule and the capsule holder and, therefore, of the device. The filter paper used is also called a non-woven fabric. Instead of composing the carrier layer of paper (filter), it is conceivable that the carrier layer is at least partly composed of another material that does not soften and/or melt in a typical operating temperature range of between 70 and 120 degrees Celsius. . Examples of alternative materials for filter paper are cellophane, cellulose acetate, and biobased and/or compostable fibers composed of viscose, lignin, and/or soy.

The sheet can conceivably comprise a plurality of carrier layers. It is also conceivable that the plurality of support layers of the film can be made weak, which leads to a weakened carrier layer. This makes it possible for the sheet to remain tearable enough while providing each carrier layer with its own functionality. For example, it is conceivable that each carrier layer may directly or indirectly play a role in supporting the oxygen barrier layer, with, for example, at least one first carrier layer functioning primarily as a carrier, while at least one other carrier layer functions More like a moisture barrier. It is preferred that at least two of the weakened foil layers are adjacent to each other. More preferably, the weakened areas of adjacent layers should be aligned with each other. This can be accomplished quite easily by applying a heated stamp or a laser that simultaneously processes the aforementioned carrier layers. The application of a stamp results in a reduced local (site-selective) layer thickness and thus a weakened area of the foil layer.

Commonly, the at least one carrier layer that is made at least partially of filter paper forms an outer layer of the sheet that faces away from the protruding engaging edge. Since this layer of filter paper is commonly used as the outer layer, this layer of filter paper will commonly interact with the cartridge holder of the device, during use of the cartridge. The oxygen barrier layer normally consists at least essentially of a polymer, preferably a compostable polymer, optionally enriched with one or more additives. The weakened layer is commonly (also) composed at least essentially of a polymer, preferably a compostable polymer, optionally enriched by one or more additives.

The laminated sheet is preferably a composite sheet (also called a composition sheet or abbreviated as composite). A composite sheet, in this case, is a sheet made of three or more individual material layers with significantly different physical or chemical properties that, when combined, produce a laminate with different characteristics than the individual layers. In the laminated sheet, the applied layers are connected to each other and are mutually indivisible. Thus, the laminated sheet as such forms a single piece of material and thus a single capsule component. Laminated sheet is commonly flexible.

In a preferred embodiment, the at least one weakened (carrier) layer is provided with perforations. The together perforations defined the weakened area (or weakened section or weakened zone) of the weakened layer. The openings made in at least one carrier layer are preferably made up of microperforations. The maximum dimension of each (micro)perforation is preferably between 1 and 10 millimeters, more preferably between 2 and 8 millimeters, and in particular between 3 and 6 millimeters. Said maximum dimension can be defined by the length, width and/or diameter of each applied (micro)perforation. In this case, it may be preferred that at least several of these openings (perforations) completely penetrate at least one carrier layer. Therefore, in this latter embodiment, at least several of the perforations form through holes connecting opposite sides of the weakened layer. Consequently, in case this perforated weakened layer is applied as a layer facing the substance retained by the shell, an adjacent foil layer will also partially face the substance retained by the capsule shell due to the through holes of the weakened perforated layer. This adjacent foil layer can be formed by the oxygen barrier layer or by another layer, such as an intermediate primer layer. However, to avoid perforation of the oxygen barrier layer, it is normally preferred that the openings do not form through holes in the weakened layer. In this case, the openings are made in a surface of the weakened layer that faces away from the oxygen barrier layer. In this case, the openings only extend to a limited depth in the weakened layer. This limited depth typically corresponds to 50-90% of the total thickness of the weakened layer. For example, in the event that the thickness of the weakened layer is 27 microns, then the openings made in a surface of the weakened layer that faces away from the oxygen barrier could have a depth of 20 microns. Therefore, in this case, the openings (of a single side) are placed at some distance from the oxygen barrier layer, which prevents unintentional damage (perforation) of the oxygen barrier layer during the production process.

The (micro)perforation can be formed quite easily by applying a laser that burns the perforation into at least one weakened layer, commonly polymer. In this case, the intensity and wavelength of the laser can be adjusted in such a way that only the weakened layer of the overlying foil layer is pierced, and that the underlying oxygen barrier layer (and other layers, if applicable) are not damaged by the laser and therefore remain intact. It is preferred in this case that the perforations are made in a pattern in at least one weakened layer. Preferably, this pattern extends over the entire surface that is bounded by the inner periphery of the engaging side edge and thus over the entire outlet side of the capsule. Experiments have shown that controlled tearing of the sheet can be best achieved if at least one perforation, and preferably each perforation, is formed by a plurality of interconnected line segments, wherein adjacent line segments are angled to each other. Said angle is therefore between, but not including, 0 and 180 degrees, and results in a weakened point where the line segments interconnect, which significantly facilitates controlled tearing of the sheet. The outer end of at least one line segment can be connected to another line segment, resulting in a perforation that would be in the shape of, for example, one of the following characters: W, E, T, Y, F , H, K, L, Z, V, N, M. It is also conceivable that at least two line segments would intersect, resulting in a perforation that would be in the form of, for example, one of the following characters: , X, £ , * , #■ It is preferred that at least two adjacent line segments mutually enclose an acute angle (angle between 0 and 90 degrees), which further improves the controlled tearing behavior of the sheet. Although typically less advantageous, simple single line segments (not interconnected with other line segments) can also be used to define boreholes. A pattern composed of a plurality of dashed lines (dashed lines or line segments) can be applied. In this pattern, preferably the dashed lines are oriented essentially parallel to one another. The perforations configured in succession forming a continuous line segment are preferably elongated, and it is particularly preferred that they are essentially rectangular. Such a design facilitates tearing of the film, wherein the film is torn at the locations of the lines, the lines determining the de facto location of the tear seams. Instead of line segments, the perforations can also be formed by points, where a pattern of points can be formed to act as a weakened area. Alternative tear patterns can be achieved, for example, by forming square and/or round shaped perforations. The thickness of the weakened layer is normally between 10 and 50 microns, preferably between 10 and 30 microns.

In an alternative embodiment variant, the at least one weakened layer is designed to be weakened by prior damage to at least one carrier layer, preferably a front side thereof, so that tearing of the carrier layer is also facilitated. Damage to the carrier layer can be done, for example, by tearing the carrier layer and/or by etching the carrier layer.

As already indicated above, the weakened layer preferably faces the substance contained in the casing. This weakened layer is then the first layer exposed to the build up of water pressure in the capsule. Due to the applied weakening, this (innermost) layer is also the first layer that can be torn by pressure buildup in the capsule during injection of water into the capsule (usually through the bottom wall of the shell), with the result that the beverage can travel through this innermost layer. Since the layers of the sheet are preferably integrally connected to each other, thus forming a composite material, tearing of the innermost layer will rather quickly lead to tearing of the other layers in the same tear pattern. Therefore, it is important to define the positioning, sizing and design of the perforations (or alternate weakenings as noted above) applied to selectively weaken the position of the weakened layer as best as possible to achieve controlled tearing of the sheet during use, and therefore a controlled outflow of beverage from the capsule. The film layers can be integrally connected to one another by welding/casting the various film layers and/or by gluing the film layers together.

Under the effect of pressure buildup in the capsule, the closure element, often simply formed by the laminated sheet, deforms and eventually undergoes a controlled tear during the interaction of the deformed sheet with a perforation structure of a device for prepare drinks such as a coffee machine. At higher temperatures between 90 and 100 °C, which are generally applied in the extraction and/or dissolution of the substance, it is specifically the oxygen barrier layer that tends to tear and form around and/or on the perforation structure of the coffee machine instead of tearing and/or puncturing. By connecting the oxygen barrier layer to the at least one weakened carrier layer, controlled rupture of the oxygen barrier layer can be forced to occur, which facilitates the beverage preparation process.

The oxygen barrier layer is preferably made, at least partially, from a material selected from the group consisting of polyvinyl alcohol (PVOH), polyvinylpyrrolidone (PVP), poly(vinyl acetate) (PVAc), compostable ethylene vinyl alcohol (EVOH ), a highly amorphous vinyl alcohol polymer (HAVOH), and nanofibrillated cellulose, derivatives and copolymers of (hemi)cellulose, and polyglycolic acid (PGA). PGA provides an even better oxygen barrier than Ethylvinyl Alcohol (EVOH) commonly used for barrier films. PVOH and HAVOH are generally the most preferred of these substances, since PVOH can be applied quite easily as an oxygen impervious sealed sheet and has favorable adhesion properties. the layer of The oxygen barrier is preferably composed of a hybrid coating of an organic phase, for example by application of at least one of the aforementioned components, and an inorganic fraction that acts as a precursor. More preferably, the inorganic fraction is composed of silicon alkoxide (Si(OR)4), where R denotes an organic glue derived from one of the aforementioned organic molecules. Such hybrid coatings generally show particularly favorable composting properties and also possess good oxygen impermeability. As a less environmentally friendly alternative, the oxygen barrier layer can also be made of, for example, poly(vinylidene chloride) (PVdC), ethenovinyl alcohol (EVOH) or a metal oxide such as SiO ² or AhO3.

The "oxygen permeability" can e.g. eg, expressed by calculating the amount (cc/m2/day) of oxygen permeated through a 20 micrometer thick oxygen barrier layer. This value (cc-20 pm/m2/day) is known as an indication of oxygen permeability. According to this calculation method, HAVOH has an oxygen permeability of 0.0023 cc-20 pm/m2/day, PVOH of 0.0050 cc-20 pm/m2/day, in EVOH of 0.42 cc-20 pm/ m2/day. Therefore, based on these oxygen barrier properties, HAVOH and PVOH are commonly more preferred than EVOH. Also, HAVOH and PVOH are better compostable than (unmodified) EVOH, which makes the use of HAVOH and PVOH more attractive. However, EVOH is more stable in wet conditions than PVOH and HAVOH, where PVOH is more stable in wet conditions than HAVOH, as a result of which PVOH is preferably used as the main component of the barrier layer. to oxygen.

Preferably, the oxygen barrier layer is also essentially impermeable to water vapor. For example, when the capsule is provided with ground coffee, it is undesirable for water to come into contact with the coffee before using the capsule to prepare the coffee. If the water vapor reaches the ground coffee before brewing, the ground coffee will absorb the water vapor and the machine will turn off. This adversely affects the quality of the coffee. This can also cause the withdrawal or infusion process to be disturbed at a later time. However, the oxygen barrier layer, including, for example, a PVOH-based oxygen barrier layer, is often sensitive to moisture, with the result that the moisture sensitive oxygen barrier will generally disintegrate with quite quickly and easily when coming into contact with moisture (water). For this reason, it is particularly preferable if the oxygen barrier layer is surrounded (sealed) on at least one side, and preferably on two sides, by at least one layer of shielding material that completely shields the oxygen barrier from the atmosphere. (containing moisture) surrounding the capsule. By surrounding atmosphere is meant the ambient air surrounding the capsule. In this case, the surrounding material layer is made from a material that is relatively insensitive to moisture and is relatively stable in a humid environment and therefore will not easily disintegrate or degrade upon contact with moisture. . Preferably, this layer of material that shields and therefore protects the oxygen barrier should be completely or at least highly impermeable to moisture, said layer of shielding material functioning as a kind of barrier layer against moisture, with the result that moisture cannot or at least cannot rapidly come into contact with the underlying moisture sensitive oxygen barrier layer. This leaves the oxygen barrier layer intact and makes the capsule and its contents more durable. In this case, complete shielding by the oxygen barrier layer from the outside world (the immediate environment) is preferred. At least one layer of shielding material, which can also function as a weakened or non-weakened carrier layer, is placed on at least one outer side of the foil to function as a partition between the moisture-sensitive oxygen barrier layer and the immediate surroundings of the sheet. A suitable material for such a shielding (carrier) layer is cellulose and/or polyhydroxyalkanoates (PHAs). Cellulose is generally (semi) transparent. Therefore, it is conceivable to apply an image that is visible to the user or a visible pattern, motif, design, text and/or information between the oxygen barrier layer and the transparent or semi-transparent shielding layer, for example by applying of ink, in particular by means of a printing process. In this way, the capsule can be effectively personalized and/or characterized, thus making it informative, recognizable and/or attractive in nature. Preferably, the screening layer is located between the oxygen barrier layer and the filter paper layer. Here, more preferably, the screening layer is glued to both the oxygen barrier layer and the filter paper layer. The thickness of the shielding layer is typically between 10 and 50 microns, preferably between 10 and 30 microns.

In a preferred embodiment, the filter paper used to compose the carrier layer has a paper density between 10 and 30 g/m2. A paper density within this range provides the carrier layer with sufficient firmness, also during use, while preventing the filter paper-based layer from becoming too heavy, which can make it difficult to tear the film and prevent it from becoming too heavy. outflow of the beverage from the capsule. For exactly the same reason, the thickness of the filter paper used to compose the carrier layer has a thickness between 30 and 100 microns, preferably between 50 and 100 microns. In order to ensure a proper filtering function of the carrier layer based on the filter layer, the filter paper used to compose the carrier layer preferably has a porosity greater than 600 l/m2 s, preferably greater than 800 l/m2 s. This porosity will normally be sufficient to allow flow through the beverage and to prevent flow through (medium sized) particles of solid substance, while avoiding too high a resistance to flow.

Preferably, the filter paper used to compose the carrier layer comprises a mixture of natural fibers and synthetic fibers, where the synthetic fibers are preferably composed of a compostable material, such as polylactic acid (PLA). In order to impart the desired properties to a nonwoven paper or fabric, it is often desired change its composition. To this end, the (filter) paper used to compose the carrier layer comprises at least one crosslinking or functionalizing agent, preferably selected from the group consisting of: polysaccharides, carboxylic acids, halogenated heteroaromatic compounds and salts thereof. It has been found that a crosslinking or functionalizing agent as described herein can impart specific desired properties to a paper or nonwoven fabric, such as high tensile strength in both the dry and wet states, even under demanding conditions, for example , extreme values of pH. The porosity, stickiness, wettability or hydrophilicity/hydrophobicity of the (filter) paper or non-woven fabric can be easily controlled to obtain the desired properties by appropriately selecting a specific crosslinking or functionalizing agent as described herein, as well as as its amount or by combining it with other additives, such as polysaccharide additives, eg carboxymethyl cellulose (CMC). The term "crosslinking or functionalizing agent" indicates a compound that is capable of binding to fibers, preferably through covalent bonds, and is capable of forming crosslinks and/or functionalizing fibers. The terms "crosslinking" as used herein not only encompasses the bonding of two fibers or one fiber and an additional additive, such as a polysaccharide additive, but also encompasses crosslinking within a fiber. The term "crosslinking" as used in this particular specification encompasses bonds (eg, two-fiber bonding, one-fiber bonding and additional additive, and/or intra-fiber crosslinking) within (within ) of the paper or non-woven fabric, and in particular not only on the surface of the paper or non-woven fabric.

The term "functionalization" as used herein means providing the paper or nonwoven fabric with a certain functionality or functionalities, such as hydrophilic properties, hydrophobic properties, wettability, adhesion, stability, tensile strength, strength, and Similar.

As already mentioned above, suitable fibers are natural fibers or cellulosic fibers. Preferred examples include cellulose, viscose, lyocell, manila, jute, cotton, hemp, sisal, rayon, abaca and other fibers, and also include softwood pulp and hardwood pulp fibers. Other suitable fibers are synthetic fibers or heat sealable fibers. Other examples include polyethylene (PE), polypropylene (PP), polyester fibers, such as polyethylene terephthalate (PET), where a preferred example includes compostable synthetic fibers, for example composed of poly(lactic acid) (PLA). Other preferred examples include bicomponent fibers, preferably bicomponent fibers of the sheath-core type. Bicomponent fibers are composed of two different types of polymers that have different physical and/or chemical characteristics, in particular different melting characteristics. A sheath-core type bicomponent fiber typically has a core having a higher melting point component and a sheath having a lower melting point component. Examples of bicomponent fibers suitable for use in the present invention include PET/PET fibers, PE/PP fibers, PET/P ^e fibers, and PLA/ ^p L ^a fibers.

As already indicated, it is also possible to use mixtures of the above fibers, such as mixtures of two or more natural fibers, mixtures of two or more synthetic fibers or heat-sealable fibers, mixtures of natural fibers and synthetic fibers or heat-sealable fibers, and any combination. from the same. The length and coarseness (weight per unit length) of the fibers are not particularly limited. The coarseness of a fiber is defined as the weight per unit length of the fiber. Typically, the natural fibers or cellulosic fibers have a length of 1 to 15 mm, preferably 3 to 10 mm. Typically, natural fibers or cellulosic fibers have a coarseness of 30 to 300 mg/km, preferably 70 to 150 mg/km. Typically, the synthetic fibers or heat sealable fibers have a length of 1 to 15 mm, preferably 2 to 12 mm. Heat sealable fibers suitable for use in the present invention typically have a coarseness of 0.1 to 5 decitex, preferably 0.3 to 3 decitex.

Tex is a unit of measurement for the linear mass density of fibers, yarns, and threads and is defined as the mass in grams per 1000 meters. The unit code is "tex", where the most commonly used unit is actually the decitex (abbreviated dtex), which is the mass in grams per 10,000 meters.

Preferably, the sheet should be essentially fully compostable. Since the capsule is made from a plurality of (biologically) compostable materials, the capsule should be disposed of after use, preferably with VFG waste (vegetable, fruit and garden waste), after which the capsule biodegrades. at the molecular level by microorganisms, where appropriate after application of activation heat and moisture (water). In this case, it is also preferred to make the components of the capsule from biomaterials ("bio-based materials"), which are materials that originate from living or formerly living organisms, as this further increases the durability of the capsule. and further reduces environmental pollution. In this process, the organic molecules, of which the capsule is essentially composed, are converted into smaller organic molecules and eventually into water, carbon dioxide and biomass (humus) and possible mineral components such as salts. In industrial composting facilities, the entire composting process usually takes several weeks. This type of composting process is also known as biodegradation. Manufacturing all capsule components from fully compostable materials provides a considerable benefit with respect to environmental contamination. This provides a solution in ongoing efforts to keep waste discharge at a manageable level and responsibly treat residual waste. In addition to the reduction in environmental contamination that accompanies the use of the capsule according to the invention, the essentially closed capsule is extremely suitable for allowing the substance, generally coffee, to be preserved for long periods of time using an oxygen barrier, preferably both both on the housing and on the closure element. For this reason, a separate container is not required to maintain the quality of the substance, specifically the coffee.

In a preferred embodiment, the sheet comprises at least one carrier layer consisting of a non-woven fabric and/or a woven fabric. The layer consisting of a non-woven fabric ( non-woven ) and/or a woven fabric ( woven) is made, for example, from polylactic acid (PLA) and/or cellulose. Polylactic acid and cellulose are compostable materials, so the capsule can be disposed of after use and biodegrade. Furthermore, both materials are relatively impervious to moisture. The layer composed of a nonwoven fabric (nonwoven) and/or a woven fabric ( woven) preferably faces the substance enclosed in the capsule. The layer serves to stiffen the foil as such, which has an open structure by nature and is therefore already configured in a weakened state and can tear quite easily. The non-woven and/or woven layer can also serve as a filter so that the ground coffee particles in the capsule cannot escape from the capsule, while the fluid (water) can penetrate. The layer consisting of a non-woven fabric (nonwoven) and/or a woven fabric (woven) can be glued to the oxygen barrier layer, for example by applying an essentially fully compostable glue, preferably made from acid polylactic acid (PLA). PLA is a compostable material, so the capsule can be thrown away after use and biodegrade. The glue layer preferably has a thickness of about 2 microns.

The capsule engaging edge is generally connected, commonly integrally connected, to an end of the peripheral wall facing away from the lower (bottom) wall. In this way, an asymmetrical capsule is obtained in the case that the symmetrical surface of the capsule is secured by the peripheral edge (flange). In general, the peripheral wall must have an essentially frustoconical design so that the capsule can be applied in known devices for preparing beverages. The bottom wall of the casing is commonly integrally connected to the peripheral wall. The bottom wall is preferably pierceable to allow water to be injected into the capsule through the bottom wall. The shell is preferably essentially rigid (holds its shape). With regard to design, the capsule should preferably be congruent with the capsule described in the aforementioned patent EP0512468.

Preferably, the shell is composed of a laminate of a plurality of layers of material. In this case, each layer of material should preferably be essentially compostable. By applying a laminate of layers of material, it is possible to efficiently endow the carcass with the desired properties. For example, at least one layer of material can form a barrier layer against oxygen and/or water (vapor). One can use e.g. e.g., a variety of synthetic or natural polymers such as nitrocellulose, polysaccharides such as hydroxyethylcellulose, poly(vinyl alcohol)(PVOH) or ethylene vinyl alcohol (EVOH), polylactic acid (PLA), poly(vinylidene chloride) (PVDC) , chitosan, carboxymethylcellulose, polyacrylate, polyglycolide, poly(butylene succinate) (PBS), acrylonitrile-butadiene-styrene (ABS), polyolefins, polyester, copolyesters, polyamide, PLA/caprolactone copolymers, polyhydroxyalkanoates, biodegradable polyethylene (PE), polypropylene (PP), polybutene (PB) and copolymers and mixtures thereof, optionally mixed with starch. An oxygen barrier layer comprising a plurality of synthetic or natural polymers may further include a crosslinker such as silane, glyoxal, melamine resin, and the like. This oxygen barrier layer is preferably made of compostable material, so natural polymers such as starch and chitosan and synthetic polymers such as PVOH, EVOH and PLA are preferred. In one embodiment, the material layer also comprises a wax and/or a filler, such as clay, which further strengthens the barrier function. Where applicable, the polymer is dispersed or dissolved in an aqueous or other solvent-based medium, said medium containing inorganic particles. Such inorganic particles are preferably composed of layered or plate-shaped inorganic particles containing natural or synthetic clay minerals such as mica, kaolinite, vermiculite, haloysite, montmorillonite and the like. Where applicable, metallized foil can also be used as an oxygen barrier and/or a water (vapor) barrier on the housing. For this purpose, an aluminum coating is preferably applied to a preform material layer of the laminate. The use of several oxygen barriers is also conceivable, which can optionally be applied one above the other. For example, it is conceivable to coat a PVOH layer with an aluminum coating. In this way, a multiple oxygen barrier is produced. An additional material layer of the laminate can optionally function as a shield coating and/or a colored layer to impart a desired color to the capsule shell. An example of such a layer is composed of a compostable polymer selected from the group consisting of compostable polyesters, PLA, polyhydroxyalkanoates, polycaprolactones, polybutylene adipate succinate, polybutylene adipate coterephthalate, PLA/caprolactone copolymers, biodegradable polyethylene, and nitrocellulose.

All of the aforementioned material layers preferably consist of a compostable material. The oxygen-impermeable barrier layer is generally sensitive to water, with the result that the barrier layer should preferably be shielded from water (vapour) by a layer of surrounding material surrounding or enclosing the barrier layer, so that the al least one surrounding material at least partially, and preferably completely, protects the barrier layer from the atmosphere surrounding the capsule. More preferably, the layer of surrounding material completely encloses the oxygen barrier layer. More details and embodiments of the capsule are described in the international patent application PCT/IB2014/002648, the entire content of which is incorporated herein by reference.

The material layers of the laminate are preferably welded or glued together by applying an essentially fully compostable glue. An example of a compostable glue that can be used in both the shell and the closure element refers to a glue containing from 1 to 70% w/w of a compostable polymer selected from the group consisting of an aliphatic or partially aromatic polyester and a urethane thermoplastic aliphatic polyester. Another example of compostable glue is made up of acrylic polymers. biodegradables, biodegradable polyesters, PLA, polyhydroxyalkanoates, polycaprolactones, polybutylene adipate succinate, polybutylene adipate co-terephthalate, PLA/caprolactone copolymers, starch, hydrocarbon resins and, of course, pine resin. Preferably, the compostable glue contains a biodegradable acrylic polymer or a polycaprolactone-based hot melt adhesive.

If applicable, the compostable glue also comprises a tackifying agent such as a resin. Such a tackifying agent preferably contains a plant resin such as a phenol rosin resin, a terpene polymer such as a terpenephenol resin and aromatic modified terpene resin, a styrene resin, coumarone/indene resin, a alkylphenol, a xylene resin, a C5 type petroleum resin, a C9 type petroleum resin and an alicyclic hydrogenated resin. Preferably, the tackifying agent comprises a plant resin such as a rosin and/or a terpene polymer, in view of the fact that said tackifying agents exhibit favorable adhesive strength in combination with the compostable polymer present in the compostable glue. .

In a preferred embodiment, a layer of the sheet that is connected to the leading edge and a portion of the leading edge to which said layer of the sheet is connected are essentially composed of the same materials. By using (essentially) the same (polymeric) materials in the contact part between the edge and the foil, a durable weld can be easily and perfectly realized. Preferably, an annular weld bead is formed by the foil and the protruding edge being welded together. An annular weld bead ensures a proper and complete connection between the sheet and the trim, where the risk of leakage of water and/or substance through a space enclosed by the sheet and the trim can be avoided.

Furthermore, an annular weld bead commonly extends through all the foil layers, where all the foil layers are pressed together at the circumferential edge of the foil layers to form the weld bead. In the weld bead, the foil layers are deformed, the deformed annular portion of the foil acting as a moisture labyrinth, which prevents or prevents atmospheric moisture from migrating into the foil layers. The moisture barrier created in this way is particularly advantageous in case one or more moisture sensitive film layers are applied, for example a PVOH-based layer (acting as an oxygen barrier layer), in where the functionality of the individual foil layer and thus the foil as such can be ensured in a relatively efficient and long-lasting manner.

The capsule as such is preferably made essentially solely of compostable biobased material, such as biodegradable biopolymers, (recycled) paper and/or cardboard, and biodegradable synthetic polymers. Biodegradable polymers preferably include biodegradable polyesters, PLA, polyhydroxyalkanoates, polycaprolactones, polybutylene adipate succinate, polybutylene adipate co-terephthalate, PLA/caprolactone copolymers, biodegradable polyethylene and nitrocellulose. PLA can comprise both the L-enantiomer (PLLA homopolymer) and the D-enantiomer (PDLA homopolymer).

In a particularly preferred embodiment, the capsule is made from a bio-based polymer (biopolymer). This relates to materials that are made from biologically renewable (recyclable) raw materials. Therefore, this refers to the origin of the materials. Examples of this are bioplastics, a term used to refer to plastics made from natural products, such as starch obtained from potatoes or corn, and also from cellulose. These are in fact artificial biopolymers. Biopolymers can be selected from carbohydrates, polysaccharides (for example cellulose, starch, glycogen, hemicellulose, chitin, fructans, inulin, lignin and/or pectin substances), rubbers, proteins, possibly cereals, vegetable and/or animal proteins (such as gluten, whey proteins and/or gelatin), colloids (as hydrocolloid, for example natural hydrocolloid as rubbers), other polyorganic acids (such as PLA, polyglycolide and polyhydroxyalkanoate (PHA)), and mixtures and/or modified derivatives thereof .

Bio-based materials can be renewed (recycled) after use, but they can also be composted. As mentioned above, composting relates to the microbiological decomposition of the materials from which the capsule is made in a relatively short period of time into at least water, carbon and biomass (humus) and possibly methane. Materials are preferably used, in particular polymers, which under strict conditions (temperature, humidity, time, etc.) are converted into water, carbon dioxide, biomass and methane within a maximum period of 6 months. These polymers meet the requirements of EN13432, an international standard for compostable polymers. This standard defines both the test program and the evaluation criteria that compostable packaging must meet, as well as the speed and degree to which a biodegradable polymer must degrade under commercial composting conditions. Whether or not a polymer product is compostable depends, among other factors, on the geometry of the product and possible additives, such as talc, compostable plasticizers, including glycerin, and/or compostable fillers, including starch.

Where applicable, the capsule is partially composed of cellulose, such as regenerated cellulose, cellophane, and/or cellulose diacetate. In cases where the casing and/or closure element are made at least partly from cellulose, the type of cellulose used should be able to withstand relatively high temperatures up to the boiling point of water. For this reason, the capsule is preferably manufactured from a composition comprising at least 20 to 90% by weight of cellulose ester, where the percentage by weight is calculated with respect to the weight of the total composition, at least 15 to 50% by weight (w/w) of a plasticizer, where the percentage by weight is calculated with respect to the weight of cellulose ester present in the composition and at least 5 to 70% by weight of an organic filler, wherein the percentage by weight is calculated with respect to the weight of the total composition.

Plasticizers are preferably selected from the group comprising glycerin, triacetin, triethylene glycol, triphenylphosphate, polyethylene glycol, propylene glycol, ethyl lactate, methyl lactate, glycerol triacetate, acetyl tributyl citrate, triethyl citrate, diethyl citrate, glycerol acetate, phthalate, sorbitol, maltitol, xylitol, erythritol, fatty acid esters and mixtures thereof. Preferably the filler comprises silicate such as talc.

Preferably, the capsule, ie the shell and/or the closure element, is made at least partly from polylactic acid or a derivative thereof. Polylactic acid can optionally be mixed with a starch to improve the decomposition rate of the material. Where applicable, the polylactic acid composite layer comprises from about 2% (w/w) to about 20% (w/w) starch. In a variant embodiment, the polylactic acid also comprises a transition metal stearate such as a stearate salt of aluminium, antimony, barium, bismuth, cadmium, cerium, chromium, cobalt, copper, gallium, iron, lanthanum, lead, lithium, magnesium, mercury, molybdenum, nickel, potassium, rare earth metals, silver, sodium, strontium, tin, tungsten, vanadium, yttrium, zinc, and zirconium. When applicable, the polylactic acid composite layer comprises about 0.5% (w/w) to about 5% (w/w) of a metal stearate. In cases where the housing and/or closure element are made at least partly of polylactic acid (PLA), the polylactic acid should be able to withstand relatively high temperatures up to the boiling point of water. However, a pure polylactic acid is generally not suitable for use due to the relatively low glass transition temperature (Tg) of 50 °C. Furthermore, polylactic acids, in particular PDLA and PLLA homopolymers, show a relatively low crystallization rate, which is generally too slow to allow sufficient crystallization during the production of the relevant components.

For this reason, it is advantageous if the material used is a liquid polylactic acid composition comprising at least 94% (w/w) acid components. It has been found that such a liquid polylactic acid composition does not crystallize above a temperature of 10°C. Therefore, said liquid polylactic acid composition can be used to form a layer of polylactic acid material that can withstand relatively high temperatures up to the boiling point of water. Preferably, the composition comprises a total concentration of acid components of at least 95% (w/w), and more preferably, the concentration of acid components is at least 96% (w/w), 97% (w/w), p), 98% (p/p), or 99% (p/p). Particularly favorable properties are obtained if the liquid polylactic acid composition contains a total concentration of acid components of 100% (w/w). It has also been found to be advantageous if the material used has a composition comprising: a compostable PLLA resin with a limited fraction (<5 mol%) of PDLA, enriched with at least one nucleating agent. Preferably, the nucleating agent comprises a combination of (i) preferably between 0 and 25% w/w of an inorganic nucleating agent, preferably talc, and (ii) preferably between 0 and 30% by weight of an inorganic filler. , preferably with a lamellar, preferably a clay mineral, in particular an aluminum mineral such as kaolin. The housing and the closing element can be made of essentially the same material composition. In this case, the common main component preferably consists of PLA and/or cellulose. If appropriate, the PLA can be selectively enriched in plates with one of a plurality of additives, to allow, for example, regulation of thermal resistance and/or elastic modulus. An additional advantage of making the housing and closure element from the same polymer is that both components can be fused together, so no glue is required.

Preferably, the capsule comprises a substantially compostable annular sealing element which is preferably attached, more preferably welded, to the protruding engaging edge and configured to substantially seal a gap between the capsule and in a capsule holder a beverage preparation device while the capsule is being filled. attached to the device. The sealing element is preferably made of a compostable material. This compostable sealing element is preferably made of polyester, more preferably of a polylactic (amorphous) acid (PLA). This amorphous structure can be obtained, for example, by injection molding the PLA at relatively low temperatures between 20 and 40 °C, preferably between 25 and 30 °C. At this low processing temperature, PLA does not have a chance to crystallize, resulting in an amorphous state. However, if the temperature is increased (above 55-60 °C), for example during regular use of the capsule, the amorphous state of the PLA will partly crystallize, resulting in a semi-crystalline state. This process is also known as "cold crystallization". At this elevated temperature of PLA crystallizing, the PLA becomes rubbery, molecular tension lowering and relaxation occurring. After pod cooling, after use, the semi-crystalline state of the PLA in the sealing element, which becomes hard and rigid at lower temperatures, will continue, significantly facilitating subsequent ejection of the pod from a pod holder. Preferably, the sealing element also contains at least one additive, in particular (inorganic) reinforcing fibers and/or talc, to improve the strength of the sealing element. It is also advantageous if the sealing element (annular) is made at least partially of a compostable thermoplastic copolyester (TPC) based elastomer to provide more flexibility to the sealing element, which can benefit the sealing ability of the sealing element. Typically, the sealing element comprises between 80 and 90% by weight of PLA. Preferably, the sealing element comprises between 10 and 20% by weight of TPC. A suitable TPC is a polymer having the molecular formula -(A)m-(B)n-, where m>1, n>1, and "A" is formed by rigid segments of polybutene terephthalate (PBT) , and "B" is made up of longer chains of soft, amorphous polyether/polyester, such as poly(tetramethylene ether glycol terephthalate). By adjusting the ratio of the "A" segments and the "B" segments, it is possible to change the TCP properties. If the sealing element comprises talc, it is also preferably 1 to 5% by weight. The addition of talc also contributes to the flexibility of the sealing element.

Preferably, the sealing element is at least partly fused to the engaging edge. This is normally achieved by welding, preferably by ultrasonic welding. Due to the fact that the contact surfaces of the engaging edge and the sealing element are usually made of substantially the same material, in particular PLA, a relatively strong connection can be produced by fusion. This makes it possible to manufacture the capsule from components that are successively joined together to form the final capsule, which usually benefits the manufacturing process and, in particular, the design and functionality of the components. Preferably, the weld seam (or fusion seam) runs completely around the (peripheral wall of the) housing, so that leakage between the latching edge and the sealing element can be avoided. It is advantageous if an outer edge of the sealing element connects to the engaging edge, whereas an inner edge of the sealing element does not connect to the engaging edge. This improves the flexibility of the sealing element (annular). In this case, it is conceivable that the width of the outer edge of the sealing element is substantially equal to the width of the inner edge of the sealing element. A part of the sealing element, including, for example (but not limited to), the inner edge of the sealing element, is preferably located at a distance from the engaging edge. As a result, gaps or air chambers are formed between the engaging edge and the sealing element, which also benefits the flexibility of the sealing element. In a preferred embodiment, the annular sealing element has a width that substantially corresponds to the width of the engaging edge. The sealing element can be made at least partly of a resilient (elastic) material. The sealing element can (also) be made at least partly of a plastically deformable material. More details and embodiments of the sealing element, in particular the sealing ring, are described in the international patent application PCT/IB2014/002648, the entire content of which is incorporated herein by reference.

The invention also relates to a laminated sheet for use in a capsule according to the invention, comprising: at least one weakened layer, weakened layer provided with at least one weakened area, at least one carrier layer that is at least partly made of paper (filter) and/or other material, preferably porous, that does not soften and/or melt at a temperature between 70 and 120 degrees Celsius, and at least one oxygen barrier layer, which barrier layer is essentially impermeable to oxygen. oxygen, and said oxygen barrier layer is positioned between said weakened layer and said carrier layer. Other embodiments and advantages of the foil have already been exhaustively described above.

The invention also refers to a method for manufacturing a capsule for preparing beverages, particularly a capsule according to the invention, comprising the steps: A) manufacturing a capsule shell, preferably from at least one compostable material, wherein the casing is essentially closed, and wherein the casing is defined by at least one peripheral wall, a bottom wall connected to the peripheral wall, and a laterally projecting engaging lip connected to the peripheral wall at a distance from the bottom wall to allow that the capsule is held in a capsule holder of a beverage preparation device; B) manufacture of a laminated sheet, sheet comprising at least one weakened layer, weakened layer provided with at least one weakened area, and weakened layer that preferably faces the substance retained by the casing, at least one carrier layer that is made by least partly of (filter) paper and/or other material that does not soften or melt in a typical operating temperature range between 70 and 120 degrees Celsius, and at least one oxygen barrier layer, barrier layer that it is essentially impermeable to oxygen, and said oxygen barrier layer is located between said weakened layer and said carrier layer, C) at least partially filling the casing with a substance to be extracted and/or dissolved, such as ground coffee, to prepare a drink; and D) connecting the sheet to the shell in such a way that the substance is enclosed in the capsule in an essentially airtight manner. Preferably, the shell is manufactured during step A) by co-injecting various essentially compostable liquefied materials into a mold, after which the shell is cooled to a temperature below the lowest melting temperature of the materials. More preferably, the shell is manufactured during step A) by co-injecting into a mold (i) at least one liquefied compostable material to form at least one oxygen barrier layer, and (ii) at least one liquefied compostable material to form the at least one layer of material surrounding the oxygen barrier layer, after which the shell is cooled to a temperature below the lowest melting temperature of the materials.

Here, during the manufacture of the shell by means of co-injection in step A), the oxygen barrier layer is preferably completely surrounded by at least one layer of surrounding material. In general, the injection of various materials into the mold is carried out successively, so that an already injected layer of material can be cooled to retain its shape before injecting one or a plurality of successive layers of material into the mold. Instead of co-injection, the shell can also be made by thermoforming, usually from a co-extruded laminate.

The manufacture of the sheet during stage B) is preferably carried out in partial stages. In a first partial step, the individual polymer film layers, including at least one carrier layer and at least one oxygen barrier layer, are first bonded to one another, for example by melting and/or gluing. In a subsequent partial step, at least one carrier layer is weakened, preferably by laser perforation of at least one carrier layer. In this case, the laser should preferably not damage the oxygen barrier layer. The initial perforation of at least one carrier layer and the subsequent gluing of the carrier layer to an additional foil layer should cause the created openings (perforations) to be filled with still-liquid glue, which it would counteract the formation of the desired weakened area of the carrier layer. Therefore, it is preferred to complete the fabrication of the laminate before performing layered and site selective perforations in the laminate.

Preferably, the method according to the invention also comprises step E) consisting in providing and connecting an annular sealing element to the engaging edge. As already stated above, the presence of a sealing element increases the sealing effect between the shell and a shell during clamping.

The manufacture of the sheet according to step B) is commonly carried out by connecting together at least one carrier layer, at least one oxygen barrier layer and at least one layer to be weakened (step B1), after which said at least one layer to be weakened is provided with at least one weakened area (step B2). Step B2) is commonly carried out by creating perforations in the layer to be weakened, preferably by means of a laser. During step B1), preferably, the oxygen barrier layer is coated onto the layer to be weakened, for example using a physical vapor deposition (VPD) technique (secondary step B1i), after which the carrier layer (at least partly made of paper) is glued to the oxygen barrier layer (secondary step B1 ii). During the secondary step B1ii, a (based) cellulose interlayer is also preferably applied, which is more preferably glued between the oxygen barrier layer and the carrier layer. This layer (based on cellulose) protects the oxygen barrier layer from damage and moisture. In a more preferred embodiment, step B1 comprises the substeps of:

B1a) B1a) apply a primer layer on a layer to be weakened,

B1b) B1b) applying an oxygen barrier layer over the primer layer, preferably by coating, for example by using a physical vapor deposition (VPD) technique,

B1c) B1c) applying a first adhesive layer on one side of the oxygen barrier layer that faces away from the primer, said first adhesive layer is preferably composed of a two-component adhesive,

B1d) B1d) applying a layer comprising cellulose on a side of the first adhesive layer facing away from the oxygen barrier layer,

B1e) B1e) applying a second adhesive layer on an outward-facing cellulose-comprising layer side of the first adhesive layer, which second adhesive layer is preferably composed of a single-component adhesive, and

B1f) B1f) applying a carrier layer, at least partly composed of (filter) paper on a side of the second adhesive layer facing away from the cellulose-based layer.

The first adhesive layer consisting of a two (or more) component adhesive does not require air to cure, which is particularly advantageous in case a moisture-sensitive oxygen barrier layer is applied in substep B1 b). The application of the oxygen barrier layer can take place under dry conditions and even under vacuum conditions, avoiding degradation of the moisture sensitive oxygen barrier during the production process. The second adhesive layer is preferably a one-component adhesive due to its lower viscosity compared to two-component adhesives, which prevents the final layer, the carrier layer made at least partly of (filter) paper, from absorbing a considerable amount of adhesive, which would hinder sheet breakage and beverage outflow during use of the sheet in a capsule.

The invention also relates to an assembly of a capsule according to the invention and a device for preparing beverages, which device comprises a capsule holder for holding the capsule. In this case, the headshell should generally comprise a plurality of headshell parts that are movable relative to each other between an open position in which the capsule can be placed in the headshell and a closed position in which the engaging edge and the sealing element of the capsule are supported by the support parts in an essentially fluid impervious manner.

The invention further relates to the use of a capsule according to the invention in a device for preparing beverages.

The invention also relates to the use of a capsule according to the invention in a device for preparing beverages.

The invention will be explained by means of the non-limiting operating examples represented in the following figures. Specifically:

figure 1 shows a schematic representation of a capsule according to the present invention,

figure 2 shows a perspective view of a capsule according to the invention,

figure 3 shows a cross section of the capsule according to figure 2,

figure 4 shows a detailed cross section of the capsule according to figures 1 and 2,

Figure 5 shows a detailed cross section of the film used in the capsule according to Figures 2-4,

figure 6 shows a view of a perforation pattern made in the film according to figure 5,

figure 7 shows a schematic representation of a method for manufacturing a capsule according to the invention,

Figure 8 schematically shows the perforation of a film according to the present invention on a perforation plate of a coffee machine;

Figures 9a-9d schematically show different forms of weakened zones according to the invention; and

Figure 10 schematically shows the connection of the film and a capsule according to the present invention.

Figure 1 shows a schematic view of a capsule 1 provided with a closure foil, also known as a closure film 2. The film 2 consists of a laminate of several layers 3, 4, 5. The first layer is an inner layer locally weakened 3, for example made of at least compostable polylactic acid (PLA) or polypropylene (PP), in which perforations 6 are applied that selectively weaken the position of the layer 3, which facilitates the tearing of the film 2 during the capsule use. The first layer 3 could comprise compostable PLA, which could form a racemic mixture. The racemic mixture provides improved thermal stability due to its (semi-)amorphous structure. The racemic mixture also improves the compostability of the first layer 3, as the PLA is arranged in a (semi-)amorphous structure as opposed to a more crystalline structure in which single enantiomer PLA would be arranged.

The first layer 3 can further comprise a filler material, such as talc. The first layer 3 can also comprise polyethylene glycol (PEG) or polybutylene terephthalate (PBT). These materials add to the viscosity of the first layer 3, which viscosity is a desired property when the first layer 3 is to be injection molded.

The first layer 3 preferably has a melting temperature of greater than 130 degrees Celsius and has a preferred thickness of less than 25 microns.

The second layer 4 is an oxygen barrier layer 4, which can be made, for example, of PVOH. The second layer 4 can be attached to the first layer 3 by means of an adhesive (not shown), but it can also be coated onto the first layer 3. The oxygen barrier layer 4 prevents oxygen from penetrating the film 2 of so that the ingredients in capsule 1 remain fresh during storage.

The third layer 5 is a paper layer 5, for example made of filter paper 5. The paper 5 preferably has a density of less than 25 grams per square meter, in particular a density between 10 and 25 grams per square meter. The paper 5 is porous, so that when the capsule 2 is used to produce coffee, the resulting liquid can flow from the capsule 2, through the filter paper 5.

The paper 5 adds structural integrity to the film 2. The paper 5 is attached, for example, to the second layer 4 by means of an adhesive (not shown). The first 3 and second 4 layers of the film 2 tend to soften when exposed to hot water temperatures typically used to prepare coffee. The first 3 and second 4 layers therefore tend to fold around a perforated plate of a coffee machine (not shown), rather than being perforated by the plate. The paper 5 prevents the first 3 and second 4 layers from doing so, since the paper layer 5 is not sensitive to temperature and maintains its structural and porous characteristics when subjected to hot water temperatures. The paper layer 5 is bio-based and may comprise cellulose fibers.

The weakened areas formed by the perforations 6 of the first layer 3 are provided, for example, by means of a laser. A laser can remove material very locally and therefore can provide weakened areas 6 very locally. The laser is used to provide the weakened areas 6 in the first layer 3 of the film 2, which means that the laser must be adjusted such that when a laser beam is applied to the film 2, only the first layer 3 is seen affected by lightning, and that the second layer 4 remains intact. Perforations 6 can form through holes made in first layer 3 connecting opposite sides of said first layer 3 and/or can selectively reduce the thickness of first layer 3 (without forming through holes).

Figure 2 shows a perspective view of a capsule 11 according to the invention. Figure 3 shows a cross section of the capsule 11 according to Figure 2. The initially essentially closed capsule 11 comprises a shell 12, having an essentially closed bottom wall 12a, a frustoconical peripheral wall 12b adjacent to the bottom wall 12a, and a laterally projecting engaging edge 12c (or flange) adjacent frustoconical peripheral wall 12b. This shell 12 is filled with coffee (not shown) and forms the base of the capsule 11. The shell 12 is manufactured using co-injection technology, with the result that the shell 12 consists of a two-layer (integrated) laminate. of PLA composite material between which a layer of material made from PVOH is configured. This composition is fully compostable. Preferably, the PLA layers are in an amorphous state. The PLA layers completely enclose the PVOH layer. The PLA layers specifically work as a moisture barrier, while the PVOH layer works as an oxygen barrier. A (lower) side of the engaging edge 12c facing away from the end side 12a is connected to an essentially compostable film 13 to enclose the coffee in the casing 12 in an essentially hermetic manner. One upper side of Latching edge 12a connects to a surface mounted sealing ring 14 (see Figure 4). The sealing ring 14 determines the maximum diameter of the capsule 11, since the latter projects with respect to the peripheral edge of the hooking edge 12c. The sealing ring 14 consists of one or more additives, such as talc, including amorphous PLA, and is therefore essentially fully compostable. As shown in figure 4, the sealing ring 14 is fused by means of two concentric weld beads 15a, 15b to the engaging edge 12c. An innermost peripheral edge 14a of the sealing ring 14 does not connect to the casing 12 and extends in an upward direction. An outermost peripheral edge 14b of the sealing ring 14 is also free and not connected to the engaging edge 12c. These free ends 14a, 14b facilitate the positioning of the sealing ring 14 during the clamping of the capsule 11 in a capsule holder, which is beneficial for the sealing capacity of the sealing ring 14.

Between the free ends 14a, 14b, the sealing ring 14 is provided with a water-repellent raised circular edge 14c which further enhances the sealing effect.

The film 13 closes the casing 12 in an essentially airtight manner and consists of an essentially fully compostable multi-layer composite, successively consisting, as shown in FIG. 5, of a locally weakened inner layer 13a made of PLA possibly provided with a primer layer, an oxygen barrier layer 13b made of PVOH, a first glue layer (two-component) 13c, a cellulose layer 13d, a second glue layer (one-component) 13e and an outer layer 13f paper (filter). The innermost layer, the locally weakened layer 13a, is processed by means of an infrared laser, causing a pattern to be made (only) on this layer 13a, with the result that the film 13 will tear more easily during use. The perforations 17, shown schematically, are preferably arranged in 11 rows, as also shown in Figure 6, where each perforation is more particularly shown to have a cross-shaped pattern defined by intersecting line segments 17', 17". The outermost film layers, particularly the oxygen barrier layer 13b, the cellulose layer 13d and the paper layer 13f are not weakly shaped and remain completely intact during laser processing.

The use of the capsule for preparing coffee can be described as follows. The capsule 1 is clamped in an open headshell (not shown), after which the headshell is closed. During closure of the shell holder, the engaging edge 12c and the sealing ring 14 attached thereto are clamped. During this clamping, the end side 12a must be pierced with piercing elements of the shell holder, and the sealing ring 14 made of amorphous PLA must be formed partly around a clamping edge of the shell holder, thus creating a seal. After this, hot water with a temperature of approximately 95 °C is introduced into the capsule holder and through the end 12a into the capsule 11. This increase in pressure causes the film 13 to deform and, as a result of the areas weakened layers (perforations) made in the layer facing the coffee 13a of the film 13, suffer a controlled tear when interacting with a perforation plate that forms part of the capsule holder. By means of this perforation plate, the coffee can be made to flow out of the capsule 11 and into the cup. During this extraction process, the sealing ring 14 will partially crystallize as a result of "cold crystallization" in semi-crystalline form. Furthermore, above the glass transition temperature (Tg) of PLA of about 55-60°C, the ring 14 will become somewhat rubbery, which enhances the sealing effect. After the extraction process, the temperature of the sealing ring 14 will drop rather quickly below the aforementioned glass transition temperature, with the result that a relatively rigid, semi-crystalline sealing ring 14 is obtained. Due to the increased rigidity compared to its initial amorphous state, the sealing ring 14 and thus the capsule 11 can be removed quite easily from the headshell.

Figure 7 shows a schematic representation of a method for manufacturing a capsule 20 according to the invention. In manufacturing the capsule 20, a laminated plastic film 21 is produced. The film 21 comprises a plurality of plastic-containing layers 21a-21f, which are described separately below.

An inner layer 21a, as shown in Figure 7, is made up of a compostable material such as PLA (polylactic acid) or compostable polypropylene (PP). The inner layer 21a could comprise compostable PLA, which can be made from a racemic mixture of left and right PLA enantiomers. The racemic mixture provides improved thermal stability. The racemic mixture also improves the compostability of the first layer 21a, as the PLA is arranged in a semi-amorphous structure as opposed to a more crystalline structure in which single enantiomer PLA would be arranged.

A back layer 21b refers to an oxygen barrier layer. This layer is relatively thin and is preferably applied to the first layer 21a during the manufacturing process of the film 21, preferably by vapor deposition. Due to the low thickness, preferably between 1 and 5 microns, and more preferably around 2 microns, of the oxygen barrier layer 21b, one can also speak of a coating. The oxygen barrier layer 21b is preferably composed at least partially of a compostable material selected from the group consisting of poly(vinyl alcohol) (PVOH), polyvinylpyrrolidone (PVP) and poly(vinyl acetate) (PVAc). PVOH is generally the most preferred of these substances, since PVOH can be applied quite easily as a dense oxygen impermeable film and has favorable adhesive properties. The oxygen barrier layer preferably consists of a hybrid coating of an organic phase, for example formed by the application of at least one of the aforementioned components, and an inorganic fraction acting as a precursor. More preferably, the inorganic fraction is composed of silicon alkoxide (Si(OR)4), where R denotes an organic glue derived from one of the aforementioned organic molecules. Such hybrid coatings they generally show particularly favorable compostability and also show satisfactory oxygen impermeability. As a less environmentally friendly alternative, the oxygen barrier layer can be made, for example, of poly(vinylidene chloride) (PVdC), ethenovinyl alcohol (EVOH) or a metal oxide such as SiO2 or Al2O3.

A third layer 21c is made up of a glue layer and is preferably made up of a compostable glue layer. This glue layer is preferably formed by a two-component adhesive (2k). An important component of this glue layer (adhesive layer) can be soy flour, which is used, for example, in combination with phenolic resin, or mixed with casein-based or sodium silicate-based adhesives.

The fourth layer 21d refers to a layer of cellulose and/or PLA. The fourth layer 21e shields the oxygen barrier layer 21b, which makes it possible to prevent damage to the oxygen barrier layer 21b. In addition, this shielding leads to a better preservation of the oxygen barrier layer 21b, since various oxygen barrier layers 21b are sensitive to moisture and disintegrate in a humid environment. By applying a moisture barrier layer, such as cellulose or PLA, it is possible to keep the oxygen barrier layer 21d intact for a longer period of time, with the result that the substance can be kept longer in the capsule. .

The fifth layer 21e is compost from a tail layer. In this case, a compostable adhesive is preferably used. This glue layer is preferably formed by a single-component component (1k). A suitable compostable adhesive is, for example, a pressure sensitive adhesive ("PSA") containing poly(D,L-lactide-co-glycolide-co-ccaprolactone).

Alternatively, a terpolymer blend comprising poly(D,L-lactide-co-glycolide-co-ccaprolactone) may be used together with another poly(D,L-lactide-co-glycolide-co-c-caprolactone) or together with a poly(D,L-lactide-coglycolide-co-mPEG). Of course, conceivable alternative adhesives can also be used.

The outer layer 21f is a paper layer 21f, for example made of filter paper. The paper preferably has a density of less than 25 grams per square meter, in particular a density between 10 and 25 grams per square meter. The paper is porous, so when the capsule is used to make coffee, the resulting liquid can flow from the capsule through the filter paper.

The paper adds structural integrity to the film. The other layer tends to soften when exposed to hot water temperatures typically used to prepare coffee and tends to fold around a perforated coffee machine plate (not shown), rather than being perforated by the plate. The paper prevents the other layers from doing so, as the paper layer is not temperature sensitive and maintains its structural and porous characteristics when subjected to hot water temperatures. The paper layer is bio-based and may comprise cellulose fibers.

After the laminated film 21 is manufactured, the film 21 is processed using an infrared laser 22 in such a way that the inner layer 21a is punctured and thus intentionally damaged and weakened. The underlying layers 21b-21f are not exposed to the laser and therefore remain intact, with the result that the film 21 is initially substantially oxygen/gas impermeable. The laser 22 performs the perforations in the top layer 21a in patterns 23, each pattern 23 being made up of a plurality of line segments. In this case, the dimensioning of each perforation is particularly small, and they have a typical length and width of the order of micrometers. Once the perforations have been made in the film 21, the film 21 is cut with a cutting element 25, such as another laser, a punch or a knife, in such a way that circular (shaped) film parts are formed. disc) that will function as a closure element 25 for a capsule.

After manufacturing the closure element formed by the processed film 21, the closure element must be applied to a casing 27 filled with ground coffee 26 (and/or some other beverage component). In this case, the casing 27 is cup-shaped and is essentially shape-retaining.

The housing 27 comprises a closed inlet side 28 (end side), a tapering side wall 29 and a laterally projecting flange 30 which functions as a latching edge. A sealing ring 31 is applied to the side of the flange 30 facing the side wall 29. The ring 31 is preferably inseparably connected to the flange 30. A more detailed description of the housing 27 and the ring 30 applied thereto is described in the applicant's international patent application number PCT/IB2014/002648, not pre-published, the content of which is incorporated herein by reference as an integral part of the content of this patent. The film 21 is glued and/or welded to the flange 30, with the result that the coffee is packed in the capsule in an airtight manner. Film 21 is oriented such that the top perforated layer faces coffee 26. Film 21 functions as the outlet side of capsule 27.

Figure 8 schematically shows a film 42 according to the invention, which could have the same composition and/or could be identical to the film 21 shown in the previous figures, which is perforated on a perforation plate 48 of a coffee machine. The film 42 comprises a paper layer 45 and a locally weakened inner layer 43. The film 42 typically also provides an oxygen barrier layer (not shown), coated onto the inner layer 43. This layer behaves similarly to the inner layer 43. Optionally, a cellulose layer (not shown) is applied. between the oxygen barrier layer and the paper layer 45.

The locally weakened inner layer 43 is provided with weakened areas 47, which are arranged to tear when subjected to pressure. When torn, the weakened areas 47 allow fluid to pass from the interior of the capsule (A) to the perforation plate 18 and through the holes 49 of the plate 48 to a beverage dispensing location (not shown). The paper layer 45 prevents the inner layer 43 from folding over the holes 49 which would make it impossible for the coffee to escape, since the paper layer 45 provides structural integrity and strength by leaving an open space between the film 42 and the perforation plate. 48 for the liquid to pass through.

Figures 9a, 9b, 9c and 9d schematically show weakened areas formed by (laser) perforations 57 of a first layer 53. The weakened areas 57 are formed by at least two interconnected line segments 57', 57", mutually enclosing a acute angle ( a) between 0 and 90 degrees.The number of weakened areas 57 is typically about twice the number of piercing elements in a coffee machine perforated plate.In diameter, the number of weakened areas 57 is typically between 8 and 16. The sharp angles between the line segments 57', 57" and thus the sharp transition between a first 57' and a second 57" line segment provide a location where the first layer 53 will typically tear. first when under pressure.

Figure 9a schematically shows weakened areas 57 in the form of intersecting lines 57 or crosses 57. The crosses 57 comprise four connected line segments 57', 57", where two of those segments 57', 57" mutually enclose an acute angle (a) about 90 degrees. Figure 3a shows approximately 14 weakened areas 57 in the diameter direction, where the weakened areas 57 are distributed substantially equally over the first layer 53.

Figure 9b schematically shows weakened areas 57 in different shapes compared to Figure 9a. The weakened areas 57 are V- and X-shaped. The X-shape basically comprises two mirror V-shapes.

Figure 9c schematically shows weakened areas 57 in different shapes compared to Figures 9a and 9b. The weakened areas 57 are in the form of Y, Z and asterisk.

Figure 9d schematically shows weakened areas 57 in different shapes compared to Figures 9a, 9b and 9c. The weakened areas 57 are L-shaped, step-shaped and lightning-shaped.

Figure 10 schematically shows the attachment of a film 62 to a capsule 61. The film 62 is attached to the flanged rim 68 of the capsule 61. The first layer 63 of the film 62 is welded to the rim 68. The second layer 64 is applied to the first layer 63 by vapor deposition and the third layer 65 is bonded to the second layer 64. The film 62, comprising the three different layers, is typically first laminated and then welded to the flange 68. The weld typically involves pressing a hot solder element onto the film 62 and capsule 61, and leaves an annular impression 69, where the film 62 is pressed or printed onto the rim 68. The impression 69 typically forms a labyrinth 69 which improves properties. of water resistance of the film 62, and in particular of one or more moisture sensitive layers of said film 62.

To enable the first layer 63 and the flanged rim 68 to be welded together, they preferably comprise the same material. The first layer 63 and the flanged rim 68, for example, comprise PLA of PP.

The same materials allow a solid and clean weld and therefore a solid connection of the film 62 and the capsule 61.

Claims (15)

1. Capsule (1, 11, 20, 61) for preparing drinks, comprising: - an essentially closed casing (12, 27) that is filled at least partially with a substance (26) to be extracted and/or dissolved, such as ground coffee, to prepare a beverage, wherein the casing (12, 27) is defined by least by a peripheral wall (12b, 29), a lower wall (12a, 28) connected to the peripheral wall, and a laterally projecting hooking edge (12c, 30, 68) connected to the peripheral wall at a distance from the lower wall to allow the capsule (1, 11, 20, 61) to be held in a capsule holder of a device for preparing beverages; and - at least one essentially closed closure element configured to allow the beverage to flow from the capsule (1, 11, 20, 61), said closure element is connected to the laterally protruding engaging edge to seal the substance in the capsule, wherein at least a part of the closure element is composed of a laminated sheet (2, 13, 21, 42, 62), wherein the sheet is configured to tear as a result of pressure buildup in the capsule when water is injected in the capsule (1, 11, 20, 61), said sheet comprising: • at least one weakened layer (3, 13a, 21a, 43, 63), said weakened layer is provided with at least one weakened area, and said weakened layer preferably faces the substance retained by the shell, • at least one carrier layer (5, 13b, 13d, 21f, 45, 65) that is at least partly made of paper and/or other material that does not soften and/or melt at a temperature between 70 and 120 degrees Celsius , and characterized by comprising • at least one oxygen barrier layer (4, 13b, 21b, 64), said essentially oxygen-impermeable barrier layer (4, 13b, 21b, 64) and oxygen barrier layer (4, 13b, 21b, 64 ) is located between said weakened layer and said carrier layer. Capsule (1, 11, 20, 61) according to claim 1, wherein the oxygen barrier layer (4, 13b, 21b, 64) is closed and the oxygen barrier layer (4, 13b, 21b, 64) is not weakened. Capsule (1, 11, 20, 61) according to one of the preceding claims, wherein the film layers are coupled to form a composite material. Capsule (1, 11, 20, 61) according to one of the preceding claims, wherein at least one carrier layer (5, 13b, 13d, 21f, 45, 65) that is made at least partly of paper forms a layer outside of the blade facing away from the protruding engaging edge. Cap (1, 11, 20, 61) according to one of the preceding claims, wherein the weakened region of at least one weakened layer (3, 13a, 21a, 43, 63) is provided with perforations (6, 17, 57), wherein the perforations (6, 17, 57) are preferably arranged in a pattern in the at least one weakened layer. Capsule (1, 11, 20, 61) according to claim 5, wherein at least one perforation is formed by a plurality of interconnected line segments (17', 17", 57', 57"), wherein the Adjacent line segments mutually enclose an angle, preferably an acute angle, and wherein at least several of the perforations (6, 17, 57) preferably form through holes connecting opposite sides of the weakened layer (3, 13a, 21a, 43, 63). Capsule (1, 11, 20, 61) according to claim 6, wherein the perforated weakened layer (3, 13a, 21a, 43, 63) faces the substance retained by the shell, and wherein the barrier layer oxygen barrier coats the weakened layer, and where preferably a primer layer is located between the weakened layer (3, 13a, 21a, 43, 63) and the oxygen barrier layer (4, 13b, 21b, 64). Cap (1, 11, 20, 61) according to one of the preceding claims, wherein the foil comprises at least one shielding layer (21e) facing to one side of the oxygen barrier layer (4, 13b, 21b, 64) facing away from the capsule shell, where the screening layer forms a moisture barrier layer, and where the screening layer is preferably located between the oxygen barrier layer ( 4, 13b, 21b, 64) and the carrier layer (5, 13b, 13d, 21f, 45, 65). Capsule (1, 11, 20, 61) according to one of the preceding claims, wherein the paper used to compose the carrier layer (5, 13b, 13d, 21f, 45, 65) has a paper density between 10 and 30g/m2. Capsule (1, 11, 20, 61) according to one of the preceding claims, wherein the paper used to compose the carrier layer (5, 13b, 13d, 21f, 45, 65) has a thickness between 30 and 100 micrometers , preferably between 50 and 100 microns. Capsule (1, 11, 20, 61) according to one of the preceding claims, wherein the film is essentially fully compostable. A laminated sheet for use in a capsule (1, 11, 20, 61) according to one of the preceding claims, comprising: • at least one weakened layer (3, 13a, 21a, 43, 63), said weakened layer is provided with at least one weakened area, • at least one carrier layer (5, 13b, 13d, 21f, 45, 65) which is made at least partly of paper, in particular filter paper and/or of another material that does not soften and/or melt at a temperature between 70 and 120 degrees Celsius, and • at least one oxygen barrier layer (4, 13b, 21b, 64), said barrier layer is essentially impermeable to oxygen, and said oxygen barrier layer is positioned between said weakened layer and said carrier layer. 13. Method for manufacturing a capsule (1, 11, 20, 61) for preparing beverages according to one of claims 1-11, comprising the steps: A) manufacturing a shell (12, 27) of the capsule, preferably from at least one compostable material, wherein the shell is essentially closed, and wherein the shell is defined by at least one peripheral wall (12b, 29), a bottom wall (12a, 28) connected to the peripheral wall, and a laterally projecting engaging lip (12c, 30, 68) connected to the peripheral wall at a distance from the bottom wall to allow the capsule to be held in a capsule holder for a beverage preparation device; B) manufacture of a laminated sheet (2, 13, 21, 42, 62), said sheet comprises at least one weakened layer (3, 13a, 21a, 43, 63), said weakened layer is provided with at least one weakened area and said weakened layer preferably faces the substance retained by the casing, at least one carrier layer being made at least partly of paper, in particular filter paper and/or other material that does not soften and/or melt at a temperature between 70 and 120 degrees Celsius, and at least one oxygen barrier layer (4, 13b, 21b, 64), said barrier layer is essentially impermeable to oxygen, and said oxygen barrier layer is located between said layer weakened and said carrier layer, C) at least partial filling of the casing (12, 27) with a substance (26) to be extracted and/or dissolved, such as ground coffee, to prepare a beverage; and D) connection of the foil to the casing in such a way that the substance is enclosed in the capsule in an essentially airtight manner. Assembly of a capsule (1, 11, 20, 61) according to one of claims 1 to 11 and a device for preparing beverages, said device comprising a capsule holder for holding the capsule. Use of a capsule (1, 11, 20, 61) according to one of claims 1 to 11 in a beverage preparation device.