WO2025177154A1 - Compostable capsule comprising a high-pressure, multi-layer cover - Google Patents

Abstract

A compostable capsule (1) for preparing beverages according to the present invention comprises a compostable, single-material plastic, cup-shaped body (2), closed at the top by a cover 6) comprising a multi layer (63) with a lower layer (631) made of plastic, welded to the edge (4) of the cup-shaped body. Advantageously, the material of the lower layer (631) is the same material as the cup-shaped body (2). This solution makes it possible to obtain, during the step of welding between the cup-shaped body and the cover, a physical/chemical bond between the two elements which is able to withstand high pressure without the risk of delamination. Advantageously, moreover, because the capsule is entirely compostable, it may be disposed of in the compostables bin, even at home.

Description

DESCRIPTION

"COMPOSTABLE CAPSULE COMPRISING A HIGH-PRESSURE, MULTILAYER COVER"

[0001]The subject matter of the present invention is a compostable capsule for preparing beverages, provided with a compostable, single-material plastic cup-shaped body, closed at the top by a cover made of the same compostable plastic as the cup-shaped body.

[0002]In the sector, capsules are known for the packaging of concentrated products (in the form of soluble or insoluble powders) in predetermined, single-use doses, for the on-demand preparation of beverages (such as coffee, cappuccino, milk and chocolate) by means of the introduction, into said capsule, of a pressurized fluid, such as hot water. The flow of hot water, delivered by an extraction machine, passes through the food powder contained inside the capsule, which results in the on- demand preparation of the beverage.

[0003]Different types of automatic or semi-automatic beverage preparation machines are known in the industry. One type of extraction involves perforating the capsule at the bottom of the cup-shaped body to allow the injection of hot water under pressure, and tearing the cover against perforating means of the extraction machine to allow the beverage to escape. In this type of capsule, the cover must be breakable, to correctly tear itself against the perforation means of the extraction machine, and provided with an internal filter, to prevent the leakage of residual coffee powder. Some examples of this type of capsule are now mentioned, wherein the cover has a filtering inner layer. US 2020/216256 Al shows a multilayer cover formed, from the outside toward the inside, of plant-based, adhesive parchment and non-woven fabric. US 2021/347547 Al describes a multi-layer cover formed, from the outside toward the inside, of a compostable polymer and a non-woven fabric. US 2020/140187 Al also describes a compostable cover in which the inner layer is made of non-woven fabric. In all these documents, therefore, the inner layer of nonwoven fabric is permeable in order to perform a filtering function, i.e., to prevent the passage of powder through the cover in the moment in which the coffee flows into the cup. As is known, the non-woven fabric (acronym NWF) is a material similar to fabric but, unlike said fabric, the fibers have a random pattern, without any ordered structure being recognizable. And just like a traditional fabric, NWF is porous, i.e., it allows the passage of air and liquids, and is therefore used as a filtering element in prior art covers. It should be noted that, precisely because NWF creates an "open" layer, in capsule covers it is necessarily associated with a "closed" layer which provides the liquid and gas seal essential for the correct preservation of the coffee powder contained in the cup.

[0004]Very different, on the other hand, is the type of capsule that is the subject matter of the present invention, suitable for use in a machine that envisages perforating the capsule on one side only to allow for the injection of pressurized hot water into the cup-shaped body. The capsule that is the subject matter of the present invention is in fact of the complex type, comprising a cup-shaped body equipped with a duct with an outlet opening for the beverage on one side and a closing cover fixed to the cup-shaped body on the opposite side, as well as the inner opening means thereof. These opening means are activated by increasing the pressure within the cup-shaped body in order to allow for the opening, by detachment or tearing, of an inner sealing disc, thus allowing the beverage to escape from the outlet duct at the bottom of the cup-shaped body.

[0005]Typically, to make and dispense the beverage, the flow of hot water is injected inside the capsule with a pressure that may reach 15 atmospheres for a time ranging from 15 to 90 seconds. It is therefore important for the manufacture of the capsule, and in particular of the cover, to select a material that provides the features necessary to resist mechanical stresses, in particular pressure, and thermal stresses to which the capsule is subjected during use.

[0006]The capsules that are currently commercially available are closed at the top by a thin cover, generally a laminate that may be perforated by the injection machine and usually comprises various layers, including a barrier layer, as well as lacquers and adhesives. The choice of a thin and easily broken lid ensures optimal perforation by the injection needle of the machine.

[0007]The main problem with prior art solutions lies in the delamination of the layers that make up the cover, especially in the case of covers made of biodegradable plastic or other biodegradable polymers. This occurs more frequently in capsules for preparing beverages from insoluble food powder, which require a higher working pressure than capsules with soluble food powder. It is indeed the high pressure that leads to the delamination of the lid, i.e., to the separation of the different layers that compose it, especially in proximity to the welding edge of the cup-shaped body, where high tension peaks are recorded. As a result of this process, there is a "fraying" of the various layers that leads to the lid tearing or detaching from the cup body resulting in leakage of liquid from the upper part of the capsule. Thus, non-compliant capsule brewing occurs because liquid spills from the upper part still end up inside the coffee cup, negatively affecting the quality of the extraction. [0008]In addition to the purely functional aspects mentioned above, keeping in view the increasing attention paid to environmental protection, the disposal of capsules after use assumes particular importance. In particular, more and more attention is paid to compostable materials, and the need is particularly felt to have capsules that may be thrown directly into the compostables bin, even at home.

[0009]The object of the present invention is to produce a capsule for the preparation of beverages that solves the problems of the prior art while taking into account the needs of the industry.

[0010]In particular, the object of the present invention is to make a compostable capsule for preparing beverages provided with a cover capable of withstanding high pressure without the risk of delamination.

[0011]This object is achieved by a compostable capsule for the preparation of beverages provided with a cup-shaped body of the compostable, single-material plastic type and closed at the top by a cover, the lower layer of which, welded to the cup, is made of the same compostable plastic as the cup-shaped body.

[0012]The features and advantages of a capsule for the preparation of beverages according to the present invention will become apparent from the following description, given by way of non-limiting example and according to the accompanying figures, wherein:

- Fig. 1 shows a capsule that is the object of the present invention;

- Fig. 2 shows the capsule of Fig. 1 being used, i.e., being perforated by the injection needle of the extraction machine;

- Fig. 3 shows an enlargement of a portion of the cover for closing the cup-shaped body of the capsule of Fig. 1. [0013]With reference to the accompanying figures, the reference numeral 1 shows a capsule for preparing beverages, in which the beverage (such as coffee, cappuccino, milk, chocolate) is obtained starting from a powdered or granular food substance, of the soluble or insoluble type.

[0014]The capsule 1 comprises a cup-shaped body 2, hereinafter simply a cup 2, adapted to define an inner volume V in which at least one food substance S is contained.

[0015]The cup 2 is a cup-like structure, produced in a single body of compostable plastic, having a slightly frustoconical shape and defined by a side wall 21 and a bottom wall 3.

[0016]The cup 2 is provided, on one side, with a bottom 3, and, on the opposite side, with an inlet opening 40 defined by an externally protruding edge .

[0017]The cup 2 is made, preferably by injection molding, of compostable, single-layer plastic. The cup 2 is therefore of the single-material type, wherein the term "single-material" refers to an object composed of a single material, a single substance.

[0018]For example, the cup 2 is made of PLA (polylactic acid) or the compounds thereof, or of PHA (polyhydroxyalkanoates) or the compounds thereof. The term "compound" refers to the material obtained by mixing the base plastic material with additives, for example light and heat stabilizers, flame retardants, antioxidants, fillers, pigments and dyes, lubricants and anti-lubricants, plasticizers, etc.

[0019]The capsule 1 comprises a cover 6 that is welded, by thermowelding or by ultrasound, to the edge 4 to seal the cup 2 on top.

[0020]The outer casing of the capsule 1 is therefore obtained by joining together the cup 2 and the cover 6, as in Fig. 2. [0021]The cover 6 is a flexible film obtained by blow extrusion or by extrusion followed by lamination.

[0022]Advantageously, the cover 6 is a film provided with a multi-layer 63, designed to be welded to the cup 2. The multi-layer 63 comprises a lower layer 631 intended to be fixed to the cup-shaped body 2. The lower layer 631 of the multi-layer 63 is made of the same material used to make the cup-shaped body 2. In particular, the lower layer 631 is made of plastic, and such plastic is the same compostable, single-material plastic used to make the cup 2.

[0023]It should be noted that the wording "same material" means that the material of the lower layer 631 is identical to the material of the cup 2. In other words, the material of the lower layer 631 is not only the same plastic (e.g., PLA), but is exactly the same material: that is, a polymer including fillers and chemical agents intended to stabilize, color, and impart mechanical properties. In still other words, the material of the lower layer 631 is completely identical to the material of the cup-shaped body 2.

[0024]As is clearly seen also from the figures, the plastic lower layer 631 is a closed layer, i.e., solid, continuous and seamless, in other words impermeable. The plastic lower layer 631 is not a porous layer, that is to say open to the passage of liquids and gases.

Advantageously, therefore, precisely because the plastic lower layer 631 is a closed layer, no further closed layers are required which provide the capsule with the liquid and gas seal essential for the correct storage of the coffee powder.

[0025]Such a solution ensures that, even at high levels of pressure inside the capsule 1, the cover 6 does not delaminate and therefore does not tear, detaching itself from the edge 4 of the cup 2 on which it is welded. By contrast, in prior art solutions, the cover is made of materials that are thermally compatible with the constituent material of the cup, but not of the same constituent material as the cup. The fact of selecting a material that is thermally compatible with the constituent material of the cup allows good welding between the cover and the cup to be obtained, but does not allow for the continuity of the material of the joined parts to be obtained. This is why, in prior art solutions, there are risks of delamination due to high pressures, i.e., greater than 10 bar or even close to 15 bar in the cases of beverages obtained from insoluble powder. In contrast, as provided in accordance with the present invention, the fact of selecting the same constituent material as the cup 2 for the lower layer 631 intended to be welded to the cup 2 allows for the continuity of the material of the joined parts to be obtained, i.e., a weld that allows for the physical/chemical bonding of the two elements, and therefore a permanent connection.

[0026]Preferably, both the cup 2 and the cover 6 have barrier properties.

[0027]Preferably, the cover 6 is provided with an inner layer 632 that forms a gas and vapor barrier. This inner barrier layer 632 is obtained by metallization of the lower layer 631 or is a film having barrier properties that is fixed to the lower layer 631.

[0028]Preferably, the inner barrier layer 632 is compostable .

[0029]Preferably, the inner barrier layer 632 is made of PVOH (polyvinyl alcohol).

[0030]Preferably, the multi-layer 63 comprises, as in Fig. 3:

- a lower layer 631 intended to be fixed to the cupshaped body 2, made of the same compostable plastic used to make the cup-shaped body 2;

- an inner barrier layer 632;

- an upper layer 633 made of plastic, preferably but not necessarily with the same compostable plastic used to make the cup-shaped body 2. [0031]Advantageously, moreover, because the cup 2 and the cover 6 are made of compostable plastic, it is possible to throw the spent capsule directly into the compostables bin, even at home.

[0032]Preferably, the cover 6 has a thickness of between 80 microns and 240 microns, preferably between 110 microns and 160 microns.

[0033]The cover 6 is of constant thickness, i.e., it is devoid of portions or zones having a reduced cross section, such as grooves or thinned areas.

[0034]The cover 6 has a lower surface 622 facing the interior of the capsule 1 once the cover 6 has been assembled on the cup 2, and an opposite external surface 623 at which the perforation by the injection needle I of the extraction machine occurs.

[0035]The patent holder has noted that, during the welding step of the cover 6 to the edge 4 of the cup 2, precisely because of the use of compostable plastic, situations sometimes occurred of the cover adhering to the welding head. To overcome this drawback, it is suggested to apply release lacquers to the welding head before welding the cover 6 onto the edge of the cup 2.

[0036]Alternatively, to promote the detachment of the cover 6 from the welding head, the cover 6 preferably comprises a paper outer layer. In this embodiment example, shown in Fig. 3, the cover 6 consists of:

- said multi-layer 63;

- a paper outer layer 62, which forms the outer surface 623 at which the perforation by the injection needle I of the extraction machine occurs.

[0037]Preferably, the cover 6 consists only of the multilayer 63 and the outer paper layer 62.

[0038]In one embodiment, the outer layer 62 is fixed to the multi-layer 63 by welding obtained in the moment in which the cover 6 is fixed to the edge 4 of the cupshaped body 2. In this example, therefore, the multilayer 63 and the outer layer 62 are supplied separately to the welding machine, overlapping each other, and then fixed to each other only at the edge 4 at the moment the cover 6 is welded to the cup-shaped body 2.

[0039]In a different embodiment example, the outer layer 62 is already fixed to the multi-layer 63. In this example, therefore, the multi-layer 63 and the outer layer 62 form a single body supplied to the welding machine which is fixed to the edge 4 of the cup-shaped body 2.

[0040]Preferably, in both of the aforementioned embodiment examples, the outer layer 62 is partially incorporated into the upper state 633 of the multi-layer 63 so as to ensure optimal adhesion between the two outer and inner layers without the need for adhesives or the need to interpose further bonding layers. It should be noted that the outer layer 62 is only partially incorporated into the upper layer 633 such that the outer surface 623 is paper to avoid the adhesion of the cover to the welding head.

[0041]The cover 6 further comprises a fixing perimeter 61 for fixing the cover to the cup 2, at the edge 4.

[0042]In one preferred embodiment example, the capsule 1 comprises a sealing disc 5, arranged inside the cup 2, making the lower closure of the capsule 1.

[0043]In effect, between the cover 6 and the disc 5 the inner volume V is defined wherein the food substance S is contained. The inner volume V is enclosed at the top by the cover 6, laterally by the walls of the cup 2 and at the bottom by the disc 5. Therefore, the lower layer 631, together with the cup 2 and the disc 5, is a closed system, i.e., a closed capsule.

[0044]At the bottom 3, the cup 2 is provided with an outlet opening 31 that is suitable for allowing the infused beverage to be dispensed. The opening 31 is the end opening of a duct referred to as a nozzle 33.

[0045]In a preferred embodiment, the cup 2 comprises therein a base provided with a plurality of vertically protruding ridges on which surface the sealing disc 5, which creates the closure of the capsule 1, is fixed by gluing or welding.

[0046]The base also comprises for example a perimeter edge 360 to which the sealing disc 5 is attached by gluing or welding.

[0047]In an embodiment example, the disc 5 is fixed to the base in an at least partially releasable manner so as to detach therefrom at least partially as a result of the increased pressure within the volume V wherein the food substance S is contained.

[0048]In a further embodiment example, the disc 5 is permanently fixed at the base and is preferably provided with weakened points (e.g., pre-cuts) so as to tear at least partially in response to the increase in pressure within the volume V in which the food substance S is contained.

[0049]In yet another embodiment example, the disc 5 is permanently fixed to the base, and the base is provided with tips suitable for at least partially perforating the disc due to the increase in pressure within the volume V in which the food substance S is contained.

[0050]In use, the capsule 1 is inserted into a special seat provided in the extraction machine, which perforates the cover 6 and introduces a pressurized fluid (usually hot water) into the inner volume V in which the food substance S is contained. The pressure exerted by the fluid inside the capsule 1 rises until it reaches a certain threshold level, or opening pressure, which pushes on the disc 5 to tear it in the case of the disc with weakened points, to detach it from the peripheral edge 360 on which it is fixed in the case of the peelable disc, or to perforate it against the tips of the base where present.

[0051]In a preferred example embodiment, the capsule 1 is a capsule for preparing beverages starting from an insoluble food substance, preferably insoluble coffee. In such an embodiment example, the capsule 1 further comprises:

[0052]- below the cover 6 and above the food substance S, fixed internally to the cup 2, a containment wall 51, said to be microperforated, compostable, provided with holes suitable for allowing the passage of the liquid under pressure and to retain the substance S;

[0053]- below the food substance S and above the sealing disc 5, fixed internally to the cup 2, a filtering wall 52, which is compostable, is provided with holes suitable for allowing the passage of the beverage and retains the food substance S.

[0054]Innovatively, a capsule according to the present invention is provided with a cover which, being a multi- layer with a lower layer made of the same compostable plastic used to make the cup, is able to withstand high pressure without the risk of delamination.

[0055]Advantageously, the capsule for preparing beverages according to the present invention is entirely compostable. With respect to known capsules composed of different plastics materials or paper or aluminum bonded materials that are very difficult to separate from each other at the time of collecting waste, the capsule that is the subject matter of the present invention is easily recyclable both for the final consumer and for those industries that decide to invest in green solutions.

[0056]Advantageously, the capsule for preparing beverages according to the present invention is entirely compostable. With respect to known capsules, this capsule may be disposed of in the compostables bin, even at home. [0057]Advantageously, compared to prior art covers having an inner layer made of nonwoven fabric, the cover that is the object of the present invention comprises a lower layer made of plastic which, being itself a closed layer, does not require additional closed layers in order to provide the capsule with the liquid and gas seal that is essential for the correct storage of the coffee powder.

[0058]It is understood that a person skilled in the art could make modifications to the capsule for the preparation of beverages described above, all of which are contained within the scope of protection as defined by the following claims.

Claims

Claims

1. A compostable capsule (1) for preparing beverages, comprising :

- a single-material, cup-shaped body (2) defined by a side wall (21) and, on one side, by a bottom wall (3), provided with a nozzle (33) ending in an outlet opening (31), and on the opposite side, by an inlet opening (40) defined by an edge (4); said cup-shaped body (2) defining an inner volume (V) in which at least one food substance (S) is contained; wherein the material of the cup-shaped body (2) is compostable plastic;

- a cover (6) in the form of film and comprising a multilayer (63) with a lower layer (631) welded to the edge (4) of the cup-shaped body (2) to close the inlet opening (40); wherein the material of the bottom layer (63) is compostable plastic; characterized in that the material of the lower layer (631) is the same material as that of the cup-shaped body (2).

2. Capsule (1) according to claim 1, wherein said compostable plastic is polylactic acid (PLA) or compounds thereof, or polyhydroxyalkanoate (PHA) or compounds thereof.

3. Capsule (1) according to claim 1 or 2, wherein said multi-layer (63) also comprises a barrier inner layer (632).

4. Capsule (1) according to claim 3, wherein said inner layer (632) is made of polyvinyl alcohol (PVOH).

5. Capsule (1) according to any one of the preceding claims, wherein said multi-layer (63) comprises:

- the lower layer (631);

- a barrier inner layer (632);

- an upper layer (632) made of plastic.

6. Capsule (1) according to any one of the preceding claims, wherein said cover (6) also comprises an outer layer (62), fixed to the multi-layer (63) on the opposite side with respect to the lower layer (631), said outer layer (62) being made of paper.

7. Capsule (1) according to claim 6, wherein said outer layer (62) is partially incorporated into the multi-layer (63).

8. Capsule (1) according to any one of the preceding claims, wherein said cover (6) has a thickness between 80 microns and 240 microns, preferably between 110 microns and 160 microns.

9. Capsule (1) according to any one of the preceding claims, wherein the cover (6) has a constant thickness, i.e., without portions with a reduced section.

10. Capsule (1) according to any one of the preceding claims, wherein said made of plastic lower layer (631) is impermeable, i.e., non-porous.

11. Capsule (1) according to any one of the preceding claims, comprising a compostable sealing disc (5), fixed at least to a peripheral edge (360) of an inner base of the cup-shaped body (2).

12. Capsule (1) according to claim 11, comprising:

- an insoluble food substance (S);

- below the cover (6) and above the food substance (S), a compostable containment wall (51), provided with through holes;

- below the substance (S) and above the sealing disc (5), a compostable filtering wall (52).