Compostable capsule with high-pressure cover

Abstract

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

Description

DESCRIPTION"COMPOSTABLE CAPSULE WITH HIGH-PRESSURE COVER"

[0001] The subject matter of the present invention is a compostable capsule for preparing beverages , provided with a compostable, monomaterial 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 product s ( 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 theperforation 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 multilayer cover formed, from the outside toward the inside, of a compostable polymer and a nonwoven fabric . US 2020 / 140187 Al also describes a compostable cover wherein the inner layer is made of nonwoven fabric . In all of these documents , therefore, the inner layer of nonwoven fabric is permeable such as to perform a filtering function, i . e . , to prevent the passage of powder through the cover in the moment wherein the coffee flows into the cup . As is known, non-woven fabric (acronym NWF ) is a material that is similar to fabric but , unlike said fabric, the fibers have a random pattern, without any ordered structure being recognizable . And as with 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 that isessential for the correct preservation of the coffee powder contained within 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, andthermal 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 upperpart 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 discarded directly in a compostables bin, also 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 obj ect 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 thepreparation 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 f rustoconical 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 "monomaterial" 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 antilubricants , 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 with a layer63, intended to be welded to the cup 2, made of the same material used to make the cup-shaped body 2. In particular, the cover 6 comprises a plastic layer 63, and such plastic is the same plastic compostable monomaterial that is used to make the cup 2. The layer 63 is the only plastic layer of the cover 6.

[0023] It should be noted that the wording "same material" means that the material of the lower layer 63 is identical to the material of the cup 2. In other words, the material of the layer 63 is not only the same plastic (e.g., PLA) , but is exactly the same material: i.e., a polymer including fillers and chemical agents intended to stabilize, color, and impart mechanical properties. In further other words, the material of the lower layer 63 is completely identical to the material of the cup-shaped body 2.

[0024] As is clearly also seen from the figures, the plastic layer 63 is a closed layer, i.e., solid, continuous and seamless, in other words impermeable. The plastic layer 63 is not a porous layer, i.e., open to the passage of liquids and gases. Advantageously, therefore, precisely because the plastic layer 63 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] The layer 63 of the cover 6 is intended to be fixedto the cup-shaped body 2 . 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 for the layer 63 that is intended to be welded to the cup 2 , the same constituent material as the cup 2 , makes it possible to obtain continuity of the material of the j oined parts , i . e . , a weld that allows for the physical / chemical union of the two elements , and therefore a permanent connection .

[0026] Advantageously, the fact that the layer 63 is the only plastic layer of the cover 6, which therefore resultsin being a plastic monomaterial cover, also ensures that , even at high levels of pressure within the capsule 1 , the cover 6 does not delaminate .

[0027] Preferably, both the cup 2 and the cover 6 have barrier properties , obtained for example by the addition of additives to the base material used to make them . The plastic layer 63 is therefore a barrier layer, and therefore, advantageously, no further barrier layers are required in the cover 6 .

[0028] Advantageously, moreover, because the cup 2 and the cover 6 are made of the same compostable plastic, it is possible to discard the spent capsule directly into a compostables bin, also at home .

[0029] Preferably, the cover 6 has a thickness of between 50 microns and 200 microns , preferably between 80 microns and 120 microns , still more preferably of about 100 microns .

[0030] 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 .

[0031] The lid 6 has a lower surface 622 facing the interior of the capsule 1 once the lid 6 has been assembled on the cup 2 , and an opposite upper surface 623 at which the perforation by the injection needle I of the extraction machine occurs .

[0032] The patent holder has noted that , during the weldingstep 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 . In such exemplary embodiment , the cover 6 consists only of said plastic layer 63 , which forms both the lower surface 622 intended to be welded to the edge 4 of the cup 2 and the upper surface 623 , and is made of the same compostable plastic material, which is monolayer, i . e . , a monomaterial, that is used to make the cup 2 .

[0033] Alternatively, in order to promote the detachment of the cover 6 from the welding head, the cover 6 preferably comprises a paper outer layer . In this exemplary embodiment , shown in Fig . 3 , the cover 6 consists of :- said inner plastic layer 63 , which forms the lower surface 622 and which is intended to be welded to the edge 4 of the cup 2 , and is made of the same compostable plastic material, monolayer, i . e . , a monomaterial, that is used to make the cup 2 ;- a paper outer layer 62 , which forms the upper surface 623 at which the perforation on the part of the inj ection needle I of the extraction machine occurs .

[0034] In such an example, shown in the figures , the cover6 consists only of the inner plastic layer 63 (the same as that of the cup-shaped body 2 ) and of the paper outer layer 62 .

[0035] In one embodiment , the outer layer 62 is fixed to the multilayer 63 by welding, obtained at the moment wherein the cover 6 is fixed to the edge 4 of the cup-shaped body 2 . In such example therefore, the multilayer 63 and the outer layer 62 are supplied separately to the welding machine, overlapping therebetween, and then fixed to therebetween only at the edge 4 at the moment the cover 6 is welded to the cup-shaped body 2 .

[0036] In a different exemplary embodiment , the outer layer 62 is already fixed to the multilayer 63 . In this example, therefore, the inner layer 63 and the outer layer 62 form a single body that is supplied to the welding machine which is fixed to the edge 4 of the cup-shaped body 2 .

[0037] Preferably, in both of the aforementioned exemplary embodiments , the outer layer 62 is partially incorporated into the inner layer 63 in such a way 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 inner layer 63 , in such a way that the upper surface 623 may be paper in order to avoid adhesion of the cover to the welding head .

[0038] The cover 6 further comprises a fixing perimeter 61 for fixing the cover to the cup 2 , at the edge 4 .

[0039] 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 .

[0040] 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 . The plastic layer 63 , together with the cup 2 and the disc 5 , therefore implement a closed system, i . e . , a closed capsule .

[0041] 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 .

[0042] 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 .

[0043] The base also comprises for example a perimeter edge 360 to which the sealing disc 5 is attached by gluing or welding .

[0044] In an embodiment example, the disc 5 is fixed to thebase 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 .

[0045] In a further embodiment example, the disc 5 is permanently fixed at the base and is preferably provided with weakened point s (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 .

[0046] 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 .

[0047] 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 itagainst the tips of the base where present .

[0048] 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 :- 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 ;- 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 .

[0049] Innovatively, a capsule according to the present invention is provided with a cover which, in being a flexible film having only one plastic layer which is made of the same compostable plastic used to make the cup, is able to withstand high pressure without the risk of delamination .

[0050] Advantageously, the capsule for preparing beverages according to the present invention consists entirely of a monomaterial . With respect to known capsules composed ofdifferent 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 .

[0051] 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 container, even at home .

[0052] 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 layer made of plastic which, being, of 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 .

[0053] 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

CLAIMS1. A compostable capsule (1) for preparing beverages, comprising :- a monomaterial cup-shaped body (2) defined by a side wall (21) and, on one side, by a bottom wall (3) , provided with a conduit (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) wherein 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 provided with a layer (63) with a lower surface (622) welded to the edge (4) of the cup-shaped body (2) to close the inlet opening (40) ; wherein the material of the layer (63) is compostable plastic and said layer (63) is the only layer of the cover (6) made of plastic; characterized in that the material of the layer (63) is the same material used for 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 claims 1 or 2, wherein said compostable plastic has barrier properties .

4. Capsule (1) according to any one of the preceding claims, wherein said cover (6) has a thickness of between 50 microns and 200 microns, preferably of between 80 microns and 120 microns, even more preferably of about 100 microns .

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

6. Capsule (1) according to any one of the preceding claims, wherein said cover (6) consists of:- said inner layer (63) ;- an outer layer (62) , which forms an upper surface (623) opposite to the lower surface (622) , said outer layer (62) being made of paper.

7. Capsule (1) according to claim 6, wherein said outer layer (62) is directly fixed to the inner layer (63) without the interposition of adhesives or other layers.

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

9. Capsule (1) according to any one of the claims from 6 to 8, wherein said outer layer (62) is only partially incorporated into the inner layer (63) .

10. Capsule (1) according to any one of the claims from 1 to 5, wherein said cover (6) only consists of the layer(63) made of plastic, wherein said plastic is the same compostable plastic used for the cup-shaped body (2) .

11. Capsule (1) according to any one of the preceding claims, wherein said plastic layer (63) is impermeable, i.e., not porous.

12. Capsule (1) according to any one of the preceding claims, wherein said plastic layer (63) is a barrier layer.

13. 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) .

14. Capsule (1) according to claim 13, 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) .

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