CAPSULE AND DEVICE FOR PREPARING BEVERAGES AND METHOD FOR PRODUCING THE CAPSULE

Abstract

The invention relates to a capsule for use in a device for preparing beverages. The invention furthermore relates to a method for producing a capsule according to the invention. The invention also relates to an assembly of such a capsule and to a device for preparing beverages.

Claims

1. Capsule for preparing beverages, comprising: a closed housing which is at least partly filled with a substance to be extracted and/or to be dissolved, such as ground coffee, for preparing a beverage, in which the housing is closed, in which the housing is at least defined by a peripheral wall, an end side connected to the peripheral wall, and a laterally projecting engagement edge which is connected to the peripheral wall at a distance from the end side for enabling the capsule to be clamped in a capsule holder of a device for preparing beverages; and at least one closed closing element which is connected to the laterally projecting engagement edge for enclosing the substance in the capsule in a preserving manner, in which the capsule is completely compostable, and in which the housing comprises at least one barrier layer, which barrier layer is impermeable to oxygen, and in which the housing comprises at least one material layer surrounding the barrier layer, in which the at least one surrounding material completely protects the barrier layer from the atmosphere surrounding the capsule.

2. Capsule according to claim 1, in which the engagement edge is connected to an end of the peripheral wall which is facing away from the end side.

3. Capsule according to claim 1, in which the peripheral wall has a substantially frustoconical design.

4. Capsule according to claim 1, in which the housing is substantially rigid.

5. Capsule according to claim 1, in which the oxygen barrier layer and the at least one material layer surrounding the oxygen barrier layer are laminated to one another.

6. Capsule according to claim 1, in which the at least one material layer surrounding the oxygen barrier layer forms a moisture barrier.

7. Capsule according to claim 6, in which the barrier layer is preferably completely enclosed by at least two surrounding material layers.

8. Capsule according to claim 6, in which the laminate comprises at least one oxygen-impermeable barrier layer which is enclosed by at least material layers, at least one material layer of which is substantially water-impermeable.

9. Capsule according to claim 5, in which the laminate is manufactured by means of co-injection.

10. Capsule according to claim 5, in which the material layers are glued to one another by using a substantially completely compostable adhesive.

11. Capsule according to claim 1, in which the housing is at least partly made from at least one compostable polyester, in particular a polylactic acid (PLA), preferably an amorphous polylactic acid (PLA).

12. Capsule according to claim 11, in which the at least one material layer surrounding the oxygen barrier is substantially made from an amorphous polylactic acid (PLA).

13. Capsule according to claim 11, in which the at least one material layer surrounding the oxygen barrier comprises at least 85% by weight of compostable polyester, in particular of a polylactic acid (PLA).

14. Capsule according to claim 11, in which the amorphous polylactic acid is enriched with at least one additive.

15. Capsule according to claim 13, in which the amorphous polylactic acid is provided with reinforcing fibres, in particular silica fibres.

16. Capsule according to claim 13, in which the amorphous polylactic acid is enriched with talc.

17. Capsule according to claim 11, in which the polylactic acid is made from sugarcane and/or sugar beet.

18. Capsule according to claim 11, in which the polylactic acid is composed of a racemic mixture of lactic acid.

19. Capsule according to claim 1, in which the oxygen barrier layer is at least partly made of a material which is substantially impermeable to oxygen selected from the group consisting of: polyvinyl alcohol (PVOH), polypropylene carbonate (PPC), compostable ethylene vinyl alcohol (EVOH), polybutene terephthalate (PBT), thermoplastic copolyester (TPC), a TPC-based elastomer (TPE), starch, a starch derivative or a combination of the aforementioned materials.

20. Capsule according to claim 19, in which the oxygen barrier layer comprises at least 70% by weight of a material which is substantially impermeable to oxygen.

21. Capsule according to claim 1, in which the oxygen barrier layer is at least partly made from an aliphatic polyol, in particular from glycerol.

22. Capsule according to claim 21, in which the oxygen barrier layer comprises at most 20% by weight of aliphatic polyol, in particular glycerol.

23. Capsule according to claim 1, in which the oxygen barrier layer is enriched with talc.

24. Capsule according to claim 1, in which the oxygen barrier layer forms between 0 and 15% by weight of the housing and/or the at least one material layer surrounding the barrier layer forms between 85 and 100% by weight of the housing.

25. Capsule according to claim 1, in which the wall thickness of the housing is between 0.3 and 0.6 millimetres.

26. Capsule according to claim 1, in which the wall thickness of the peripheral wall of the housing is greater than the wall thickness of the engagement edge of the housing.

27. Capsule according to claim 1, in which the wall thickness of the peripheral wall of the housing is greater than the wall thickness of the end side of the housing.

28. Capsule according to claim 25, in which the total wall thickness of the peripheral wall is between 0.4 and 0.6 millimetre, and the wall thickness of the engagement edge and/or the end side is between 0.3 and 0.4 millimetres.

29. Capsule according to claim 1, in which the layer thickness of the oxygen barrier layer is smaller than the layer thickness of at least one material layer surrounding the oxygen barrier layer.

30. Capsule according to claim 1, in which the capsule comprises a substantially compostable substantially annular sealing element which is preferably attached to the engagement edge and configured to substantially seal a space between the capsule and a device for preparing beverages while the capsule is clamped in the device.

31. Capsule according to claim 30, in which the sealing element is at least partly made from at least one compostable polyester, in particular a polylactic acid (PLA).

32. Capsule according to claim 31, in which the sealing element is at least partly made from an amorphous polylactic acid (PLA).

33. Capsule according to claim 31, in which the sealing element is at least partly made from a composite material which comprises (i) at least one compostable polyester, in particular a polylactic acid (PLA), preferably an amorphous polylactic acid (PLA), and (ii) at least one elastomer based on thermoplastic copolyester (TPC).

34. Capsule according to claim 33, in which the composite material comprises talc.

35. Capsule according to claim 30, in which at least a part of the sealing element is fused with the engagement edge.

36. Capsule according to claim 35, in which only an outer edge of the sealing element is fused with the engagement edge, and in which an inner edge is not directly connected to the sealing element.

37. Capsule according to claim 36, in which the width of the outer edge of the sealing element is substantially equal to the width of the inner edge of the sealing element.

38. Capsule according to claim 35, in which a part of the sealing element is situated at a distance from the engagement edge.

39. Capsule according to claim 30, in which the width of the sealing element substantially corresponds to the width of the engagement edge.

40. Capsule according to claim 30, in which the sealing element increases the effective diameter of the capsule.

41. Capsule according to claim 1, in which the capsule is at least partly made from at least one biobased material.

42. Capsule according to claim 1, in which the closing element is formed by a substantially completely compostable film/foil.

43. Capsule according to claim 1, in which the closing element is glued to the housing by using a substantially completely compostable adhesive.

44. Capsule according to claim 43, in which the adhesive comprises 1 to 70% by weight of compostable polymer, selected from the group consisting of: an aliphatic or partly aromatic polyester, and a thermoplastic aliphatic polyester urethane.

45. Capsule according to claim 1, in which the capsule housing is at least partly made from cellulose.

46. Housing for use in a capsule according to claim 1.

47. Annular sealing element for use in a capsule according to claim 30.

48. Method for producing a capsule for preparing beverages, in particular a capsule according to claim 1, comprising the following steps: A) manufacturing a housing of the capsule from at least one compostable material, in which the housing is substantially closed, in which the housing is at least defined by a peripheral wall, an end side connected to the peripheral wall and a laterally projecting engagement edge which is connected to the peripheral wall at a distance from the end side for clamping the capsule in a capsule holder of a device for preparing beverages; B) manufacturing a closing element from at least one compostable material, C) at least partly filling the housing with a substance to be extracted and/or dissolved, such as ground coffee, for preparing a beverage; and D) attaching the closing element to the housing in such a way that the substance is enclosed in the capsule in a substantially airtight manner, in which the housing comprises at least one barrier layer, which barrier layer is substantially impermeable to oxygen, and in which the housing comprises at least one material layer surrounding the barrier layer, in which the at least one surrounding material completely protects the barrier layer from the atmosphere surrounding the capsule.

49. Method according to claim 48, in which the housing is manufactured in step A) by means of co-injecting in a mould at least one liquefied compostable material in order to form the at least one oxygen barrier layer, and at least one liquefied compostable material in order to form the at least one material layer surrounding the barrier layer, following which the housing is cooled to a temperature below the lowest melting temperature of the materials.

50. Method according to claim 49, in which, during manufacture of the housing by means of co-injection in step A), the oxygen barrier layer is completely enclosed by at least one surrounding material layer.

51. Assembly of a capsule according to claim 1, and a device for preparing beverages, which device comprises a capsule holder for receiving the capsule.

52. Assembly according to claim 51, in which the capsule holder comprises several holder parts which are displaceable with respect to one another between an open position, in which the capsule can be placed in the capsule holder, and a closed position, in which the engagement edge and the sealing element of the capsule are clamped substantially in a liquid-tight manner by the holder parts.

53. Assembly according to claim 52, in which the housing and the sealing element are perforated in the closed position of the capsule holder.

54. Use of a capsule according to claim 1 in a device for preparing beverages.

Description

[0042] The invention will be explained by means of the non-limiting illustrative embodiments shown in the figures below, in which.

[0043] FIG. 1 shows a cross section of a capsule according to a first embodiment of the present invention;

[0044] FIG. 2 shows a cross section of a capsule according to FIG. 1, provided with a protective layer;

[0045] FIG. 3 shows a cross section of a capsule according to a second embodiment of the present invention;

[0046] FIG. 4 shows a cross section of a capsule according to FIG. 3, provided with a protective layer;

[0047] FIG. 5 shows a cross section of a housing according to a first embodiment of the present invention;

[0048] FIG. 6 shows a cross section of a capsule according to FIG. 5, provided with a protective layer;

[0049] FIG. 7 shows a cross section of a housing according to a second embodiment of the present invention;

[0050] FIG. 8 shows a cross section of a capsule according to FIG. 7, provided with a protective layer;

[0051] FIG. 9 diagrammatically shows a cross section of a capsule according to a first embodiment of the present invention, provided with a surface-mounted non-attached sealing ring;

[0052] FIG. 10 diagrammatically shows a detail of the sealing ring in a non-attached position;

[0053] FIG. 11 diagrammatically shows a cross section of a capsule according to a first embodiment of the present invention, provided with a surface-mounted attached sealing ring; and

[0054] FIG. 12 diagrammatically shows a detail of the sealing ring in an attached position.

[0055] FIG. 1 shows a cross section of a capsule (1) according to a first embodiment of the present invention. The initially substantially closed capsule (1) comprises a housing (2) with a frustoconical peripheral wall (3) and a laterally projecting engagement edge or flange (4) which adjoins the frustoconical peripheral wall (3). This housing (2) is, for example, filled with coffee (not shown) and forms the basis of the capsule (1).

[0056] The housing (2) is manufactured, for example, by means of a co-injection technique, as a result of which the housing (2) is composed of an (integrated) laminate of two material layers (5, 6) made of PLA, between which a material layer (7) made of PVOH is arranged. This construction is completely compostable. Preferably, the PLA layers (5,6) are in the amorphous state. In this case, the PLA layers (5,6) enclose the PVOH layer (7) completely. The PLA layers (5, 6) act mainly as a moisture barrier, whereas the PVOH layer (7) acts as an oxygen barrier.

[0057] A(n) (under)side of the engagement edge (4) is attached to a substantially compostable film/foil (8) in order to enclose the coffee in a substantially medium-tight manner in the housing (2). The film/foil (8) is preferably also impermeable to water and oxygen. To this end, the film/foil (8) may be composed of several layers of film/foil.

[0058] FIG. 2 diagrammatically shows the cross section of a capsule (1) according to FIG. 1. In addition, the capsule (1) is provided with a protective layer (9) of cellulose which is provided on the outer PLA layer (5). This protective layer (9) forms an additional oxygen barrier and moisture barrier to protect the coffee in the capsule (1).

[0059] FIG. 3 shows a cross section of a capsule (11) according to a second embodiment of the present invention. The initially substantially closed capsule (11) comprises a housing (12) with a frustoconical peripheral wall (13) and a laterally projecting engagement edge or flange (14) which adjoins the frustoconical peripheral wall (13). This housing (12) is, for example, filled with coffee (not shown) and forms the basis of the capsule (11) and is composed of a layered structure having a PLA layer (15) on the outer side and a material layer (17) made of PVOH on the inner side. This compound is completely compostable. Preferably, the PLA layer (15) is in the amorphous state.

[0060] A(n) (under)side of the engagement edge (14) is attached to a substantially compostable film/foil (18) in order to enclose the coffee in a substantially medium-tight manner in the housing (12). The film/foil (18) is preferably also impermeable to water and oxygen. To this end, the film/foil (18) may be composed of several layers of film/foil.

[0061] In this case, the PLA layer (15) and the film/foil (18) together enclose the PVOH layer (17) completely. The PLA layer (15) and the film/foil (18) act mainly as a moisture barrier, whereas the PVOH layer (17) acts as an oxygen barrier.

[0062] FIG. 4 diagrammatically shows the cross section of a capsule (11) according to FIG. 3. In addition, the capsule (11) is provided with a protective layer (19) of cellulose which is provided on the outer PLA layer (15). This protective layer (19) forms an additional oxygen barrier and moisture barrier to protect the coffee in the capsule (11).

[0063] FIG. 5 diagrammatically shows a cross section of a housing (22) according to a first embodiment of the present invention. The housing (22) is provided with a frustoconical peripheral wall (23) and a laterally projecting engagement edge or flange (24) which adjoins the frustoconical peripheral wall (23).

[0064] The housing (22) is, for example, made by means of a co-injection technique, as a result of which the housing (22) is composed of a(n) (integrated) laminate of two material layers (25, 26) made of PLA, between which a material layer (27) made of PVOH is arranged. This construction is completely compostable. Preferably, the PLA layers (25, 26) are in the amorphous state. In this case, the PLA layers (25,26) enclose the PVOH layer (27) completely. The PLA-layers (25, 26) act mainly as a moisture barrier, whereas the PVOH layer (27) acts as an oxygen barrier.

[0065] FIG. 6 diagrammatically shows the cross section of a housing (22) according to FIG. 5. In addition, the housing (22) is provided with a protective layer (29) of cellulose which is provided on the outer PLA layer (25). This protective layer (29) forms an additional oxygen barrier and moisture barrier to protect the coffee in the housing (22).

[0066] FIG. 7 shows a cross section of a housing (32) according to a second embodiment of the present invention. The housing (32) is provided with a frustoconical peripheral wall (33) and a laterally projecting engagement edge or flange (34) which adjoins the frustoconical peripheral wall (33). This housing (32) is composed of a layered structure having a PLA layer (35) on the outer side and a material layer (37) made of PVOH on the inner side. This construction is completely compostable. Preferably, the PLA layer (35) is in the amorphous state.

[0067] FIG. 8 diagrammatically shows the cross section of a housing (32) according to FIG. 7. In addition, the housing (32) is provided with a protective layer (39) of cellulose which is provided on the PLA layer (35). This protective layer (39) forms an additional oxygen barrier and moisture barrier to protect the coffee in the housing (32).

[0068] FIG. 9 diagrammatically shows a cross section of a capsule (41) according to the first embodiment of the present invention. The capsule (41) comprises a housing (42) with a frustoconical peripheral wall (43) and a laterally projecting engagement edge or flange (44) which adjoins the frustoconical peripheral wall (43). This housing (42) is, for example, filled with coffee (not shown) and forms the basis of the capsule (41). On the top side of the engagement edge (44), the housing (42) is attached to a surface-mounted sealing ring (50). The sealing ring (50) is made of amorphous PLA provided with one or more additives, such as talc, and is thus substantially completely compostable. The sealing ring (50) is not yet attached to the engagement edge (44).

[0069] FIG. 10 diagrammatically shows a detail of the sealing ring (50) and the engagement edge (44) in the non-attached position. On the underside of the ring (50), weld seams (51, 52) are present which can be welded together with the engagement edge (44). The outer peripheral edge (53) of the ring (50) is situated on the engagement edge (44) and can also be welded together with the engagement edge (44). The sealing ring (50) is also provided with an upright circular water-retaining edge (54) which further improves the sealing effect. An inner peripheral edge (55) of the sealing ring (50) is not connected to the housing (42) and extends upwards. This facilitates folding of the sealing ring (50) when the capsule (41) is being clamped into a capsule holder, thus benefitting the sealing capacity of the sealing ring (50).

[0070] FIG. 11 diagrammatically shows a cross section of a capsule (41) according to the first embodiment of the present invention and according to FIG. 9, in which the sealing ring (50) is welded to the engagement edge (44).

[0071] FIG. 12 diagrammatically shows a detail of the sealing ring (50) and the engagement edge (44) in the attached position. The sealing ring (50) is fused to the engagement edge (44) by means of a weld seam (52). The outer peripheral edge (53) of the ring (50) is also welded to the engagement edge (44). At least two air chambers (56, 57) are situated between the sealing ring (50) and the engagement edge (44) of the capsule (41), one between the free end (55) and the engagement wall (44) and one between the two weld seams (51, 52). At the location of the air chambers (56, 57), the sealing ring (50) is more resilient and there is space for the sealing ring (50) to move in the direction of the flange (44). In this way, the sealing ring (50) can adapt better to the shape of a capsule holder (not shown) of a coffee machine.

[0072] The use of the capsule for preparing coffee can be described as follows. The capsule (41) is positioned clamped in an open capsule holder (not shown), after which the capsule holder is closed. During closing of the capsule holder, the engagement edge (44) and the sealing ring (50) attached thereto are clamped. In the course of clamping, the end side will be perforated by perforation elements of the capsule holder and the sealing ring (50) made from amorphous PLA will partly shape around a clamping edge of the capsule holder, thus creating a seal. Thereafter, hot water at a temperature of approximately 95 C. is passed into the capsule holder and into the capsule (41) via the end side. As a result of this increase in pressure, the film/foil (not shown) will bulge and will be perforated by a perforation plate which forms part of the capsule holder, as a result of which coffee can be passed out of the capsule (41) and can be collected in the cup.

[0073] During this extraction process, the sealing ring (50) will partly crystallize to a semicrystalline state due to a cold crystallization. In addition, the ring (50) will become slightly rubbery above the glass transition temperature (Tg) of PLA of approximately 55-60 C., which benefits the sealing effect. After the extraction process, the temperature of the sealing ring (50) will drop below the abovementioned glass transition temperature relatively quickly, as a result of which a relatively stiff, semicrystalline sealing ring (50) is obtained. Due to the increased stiffness compared to the initial amorphous state, the sealing ring (50), and thus the capsule (41), can be removed relatively easily from the capsule holder.

[0074] It will be clear that the invention is not limited to the illustrative embodiments illustrated and described herein, but that countless variants are possible without departing from the scope of the attached claims which will be obvious to the person skilled in the art.