AU2023207781A1

AU2023207781A1 - Portion capsule

Info

Publication number: AU2023207781A1
Application number: AU2023207781A
Authority: AU
Inventors: Ralf MÜLLER
Original assignee: Tchibo GmbH
Current assignee: Tchibo GmbH
Priority date: 2022-01-11
Filing date: 2023-01-10
Publication date: 2024-08-01
Also published as: CN118742495A; WO2023135137A1; EP4209431A1

Abstract

A portion capsule (1) filled with an extraction material for the production of a brewed product has, in a manner known per se, a main body made of plastic and a lid (3) fastened thereto. The main body forms a bottom region, a peripheral side wall and, adjoining the peripheral side wall towards a lid side, a peripheral main body collar. The lid has a lid collar whose inner side is welded to the main body collar in such a way that the main body collar and the lid collar jointly form a collar (4) of the capsule. The main body and lid together form a capsule which encloses the extraction material. The capsule has a substantially rectangular, in particular square, outline by virtue of the main body having, at least in the region of the collar, a substantially rectangular, in particular square, outline. The collar has, on the lid side, a plurality of ribs (50) which extend so as to be non-parallel to, that is to say at an angle to, the side wall.

Description

PORTION CAPSULE

The invention relates to the preparation of drinks or the like from an extraction material, for example ground coffee, which is contained in a capsule. In particular, it relates to a portion capsule.

Extraction apparatus for preparing drinks from an extraction material which is present in a portion package are known for example as coffee machines, espresso machines or also tea machines. In many corresponding systems, the portion packages are designed as capsules, in which the extraction material is closed off, for example in an airtight manner. For the extraction, the capsule is pierced at two sides which are opposite one another. A brewing fluid - generally hot water - is introduced at the first side. The brewed product is led out of the capsule at the second side. Herein, quite a considerable pressure must prevail in the inside of the capsule, depending on the drink to be prepared and the system.

Coffee portion capsules which approximately have a cube shape and are manufactured of plastic are known from WO 2010/118543 and WO 2015/096989 and in contrast to the known beaker-like capsules have no collar which is circumferential at the plane of the one (upper-side) cover surface. Such a circumferential collar with capsule systems according to the state of the art is necessary amongst other things for closing the capsule by a foil which serves as a lid. In contrast to this, an arched lid is used according to WO 2010/118543 and WO 2015/096989. The capsule which is manufactured according to the teaching of WO 2010/118543 accordingly has a welding brow which forms a collar and is circumferential between the planes defined by the cover surface and whose extension / lateral protrusion however is significantly reduced compared to collars of known capsules. An energy director is necessary for the welding, said energy director being formed by a circumferential rib and being able to be present on the beaker (according to WO 2010/118543) or on the lid (according to WO 2015/096989). Concerning the solution according to WO 2015/096989, the rib is formed by way of a circumferential groove (flute) being shaped on the lid from the upper side (thus from the side which is opposite to the side with the energy director), for example by way of the thermoforming method. Thus a groove which is running circumferentially in the circumferential direction is formed on the capsule according to WO 2015/096989, for the purpose of forming the energy director.

In particular, aluminium and plastics, for example polypropylene have become known as capsule materials. So-called bio-plastics have also already been discussed as capsule materials. On the one hand plastics which are manufactured from a renewable raw material (so-called bio based plastics) are denoted as such. On the other hand, bio-plastics are plastics which are biologically degradable (so-called biodegradable plastics). The plastics which have been suggested for the manufacture of portion capsules are biodegradable and partly comprise a share of bio-based plastics.

In the present text, "biodegradable" means biologically degradable according to the standard EN13432 (dated: end of 2020), and "bio-based" means "of renewable raw materials, not based on fossils".

The available bio-plastics, in particular biologically degradable plastics have the characteristic of softening already at relatively low temperatures and thus having a certain flowability already at low temperatures (low glass transition temperature), but of having to be heated to quite a high extent until they become completely flowable (i.e. the melting temperature, inasmuch as is defined, is not particularly low). This results in particular challenges on welding, since a transition into a very flowable state (defined via the melting temperature inasmuch as this is concerned) is a precondition for a reliable welding, which is why the time interval during which material is basically flowable is larger than with conventional plastics.

Plastic capsules of the type which are described in WO 2010/118543 and in WO 2015/096989 have proven their worth. However, their manufacture entails a certain effort. Furthermore, due to the sharp-edged ultrasound tool which is to be used and which is described in WO 2015/096989, it is quite a challenge to adequately protect the diffusion barrier layer which is present in plastic capsules, in the region of the welding.

It is therefore an object of the present invention to further improve the characteristics of capsules of this type, in particular with regard to the manufacturability and in particular with regard to the ability to use different materials, amongst these bio-plastics.

This object is achieved by the invention as is defined in the patent claims.

A portion capsule which is filled with extraction material for the manufacture of a brewed product, in a manner known per se comprises a main body of plastic as well as a lid which is fastened to this. The main body forms a base region, circumferential side wall and a circumferential main body collar which connects to the circumferential side wall towards a lid side. The lid comprises a lid collar whose inner side is welded to the main body collar, so that the main body collar and the lid together form a collar of the capsule. The main body and the lid together form a capsule which encloses the extraction material. The capsule has an essentially rectangular, in particular square horizontal section by way of the main body at least in the region of the collar having an essentially rectangular, in particular square horizontal section. The collar comprises a plurality of ribs which do not run parallel, thus at an angle with respect to the side wall, and which run at the lid side

The ribs have the following function: with torsional welding - torsional welding is a method which is known per se and which is not described in more detail here - they serve for the engaging of a tool, so that rotation oscillations of the lid relative to the main body are made possible. This is independent of whether the ribs are produced by this tool or are produced in a separate step.

After the welding procedure, the ribs can contribute to the stability of the connection between the main body and the lid by way of them structuring the welding. By way of this, they act in a stabilising manner in particular with regard to shear forces between the main body and the lid.

It has been found that the combination of such ribs with torsional welding firstly produces a good welding strength with many plastic materials, and specifically with a low material deformation. What is particularly advantageous is the fact that on account of this, different materials are available for the capsule, amongst these in particular also bioplastics.

Secondly, any present barrier layer remains intact. The barrier layer in plastic capsules is a layer which is integrated in the wall and which increases the oxygen sealedness of the capsule in comparison to a construction only of the plastic (for example polypropylene or bioplastics), by which means of example an oxygen-tight repackaging of the capsule can be done away with. One example of a barrier layer material is EVOH (ethylene vinyl alcohol copolymer). Such a barrier layer can be integrated for example in the inside of the capsule material in a sandwich like manner between plastic layers. A conventional plastic welding method with an energy director can locally destroy the barrier layer at the location of the energy director. This disadvantage is avoided by way of the ribs and the torsional welding which is rendered possible by way of these, wherein the mentioned stabilising effect remains despite this, in particular with regard to shear forces.

Thirdly, further advantages with regard to manufacturing technology also arise, amongst these shorter welding times.

A recognition on which the invention is based is the fact that the mentioned advantages of the ribs in the collar which partly relate to the torsional welding, indeed also result with non round, but indeed rectangular cross sections, although torsional welding actually entails rotation movements (rotation oscillations).

The number of ribs can be selected according to requirements, wherein generally a greater number is present, for example in total at least 20 or at least 30, or at least 40 or also 60 and more. A maximal number can -justified by the dimensions of the capsule - lie for example at 150 or 120 or 100. The width of the ribs and their distances can be of a similar size to the extent that they form a rib-groove pattern. For example, the average distance between adjacent ribs can be smaller or equal to fivefold, fourfold or threefold their average width, so that the width of the groove between the ribs is not more than fourfold, threefold or double the size of the rib itself The relative dimensions of the ribs and the grooves which lie therebetween does not need to be constant along the periphery of the capsule, but can also markedly vary, for example in the region of the (rounded) corners of the collar with ribs which are significantly wider than the grooves therebetween, and in the middle between the corners with ribs which are roughly equally wide as the grooves or also significantly less wide.

As mentioned, the ribs run at an angle with respect to the side wall and to the course of the collar, for example in a roughly perpendicular manner. The ribs can run for example in a roughly radial manner.

"Radial" and "axial" in this text always relate to the axis of the capsule which runs centrally through the capsule and perpendicularly to the plane which is defined by the collar (and generally also to the plane of the capsule base and a lid plane). This axis is also related to the function of the capsule: on brewing, the liquid flows axially, i.e. from the capsule base towards the capsule lid (or vice versa).

In particular, the ribs can run from the inside to the very outside on the collar, up to a radially outer edge.

The ribs are present on the collar at the lid side, thus are formed in the lid-collar. However, they can also have the effect that the welding - thus the transition between the lid collar and the main body collar, inasmuch as still defined - itself has a certain rib-groove pattern (wave pattern), so that also a certain toothing results additionally to the material fit, which contributes to the mentioned additional stabilisation.

As is known per se from WO 2010/118543 and WO 2015/096989, it is possible for the lid not to be flat, but arched outwards (with respect to the inside of the capsule), thus axially outwards, i.e. an axial end-side lid face is offset axially outwards with respect to the plane which is defined by the collar. According to this embodiment, the lid therefore differs from a flat, for example foil-like or plate-like lid element. It is a three-dimensionally shaped body. In particular, the lid can be manufactured by thermoforming or alternatively by way of injection moulding, which can also apply to the main body.

In such embodiments, the shape of the lid from the outside to the inside can comprise the lid collar, an arcuate transition region and a central flat region which forms the actual upper-side cover surface. The transition region can be for example arcuate in an S-shaped manner or runs in a constant arcuate manner from an outer portion which is at an angle with respect to the plane of the collar towards the central flat region. Herein, the dimensioning is selected for example such that the central flat region optically dominates, for example by way of it be equally large or only insignificantly smaller (for example maximal 10%) than the base surface. In particular, one can envisage this flat region assuming more than 60% of the diameter and accordingly at least 40% of the surface.

The lid-collar generally forms a circumferential face which faces the lid side - with the ribs, if these are present at the lid side - said surface extending from an outer edge of the collar to a beginning of the arching. In embodiments, one can envisage the beginning of the arching being offset inwards compared to the portion of the main body side wall, onto which the collar connects. Such an offset can be for example at least 0.2 mm.

In embodiments, the main body and/or lid can be present for example as a multi-layer system with bio-plastic (for example Ecovio)/PVOH/bio-plastic, wherein PVOH forms the diffusion barrier layer. A so-called tie-layer , i.e. an adhesive layer can be arranged between the PVOH layer and the bio-plastic, in particular for deep-drawable layer systems, so that the construction can then be bio-plastic/tie/PVOH/tie/bio-plastic. Biodegradable tie-layers are now known and are obtainable on the market, for example as natural waxes.

As an alternative to the design of bio-plastic, the main body and the lid can also be designed from a different plastic - for example with a diffusion barrier layer - for example of polypropylene.

The plastic material of the lid and that of the main body can be identical. However, it is also possible for the lid to consist of a plastic of another composition which however can be welded to the main body plastic.

A wall thickness in the region of the main body in particular is between 0.2 mm and 0.4 mm, for example between 0.25 mm and 0.35 mm. The same can also apply to the wall thickness of the lid. In an embodiment, the wall thickness of the lid corresponds roughly to the wall thickness of the main body.

A particular optional feature can be for the main body to form a thickening in the region of the transition between the circumferential side wall and the main body collar, said thickening forming a radially inwardly projecting bead. This serves for the stiffening in the region of the collar.

The capsule - and this applies to all embodiments, also of the first aspect - in particular can be designed such that the main body and the lid together completely encompass the extraction material without an opening which is covered for example by a foil or the like. In particular, it can be hermetically sealed and oxygen-tight, for example by way of it having a suitable diffusion barrier.

Embodiment examples of the invention are hereinafter described by way of drawings. In the drawings, the same reference numerals denote the same or analogous elements. The drawings are not true to scale and show elements which partly correspond to one another in sizes which vary from figure to figure. There are shown: - Fig. 1 a capsule; - Fig. 2 a main body for the manufacture of a capsule according to Fig. 1; - Fig. 3 a lid according to the state of the art, drawn in a sectioned manner; - Fig. 4 a view of a capsule according to the invention; and - Fig. 5 a section through the capsule, said section only being represented in the region of the welding and only partially.

The capsule according to Figure 1 essentially has the shape of a cube with rounded edges. However, the extension slightly increases towards the upper-lying side, so that seen in a strictly mathematical sense has the shape of a truncated pyramid. The inclination angle of the surfaces which are lateral in the figure, with respect to a perpendicular to the base surface 5 what is meant of course is that plane perpendicular to the base surface which runs through the edge between the base surface and the respective lateral surface - is very small, it is preferably 2 at the most, for example only approx. 10. Furthermore, the height of the capsule above the base surface approximately corresponds to the length of the base surface edges.

The capsule comprises a main body (or beaker) 2 and a lid 3 which is fastened thereto along a circumferential collar 4. The main body 2 forms a capsule base 5 and a circumferential side wall 6 which at its end which is at the outside with regard to axial directions (axis 10) and is at the top in Fig. 1 is terminated by the collar 4. The lid is arched to the outside by way of the lid face 9 which is essentially parallel to the capsule base 5 being set outwards in comparison to the circumferential collar 4, thus to the top in Fig. 1.

Figure 2 shows the main body 2 (beaker) before the filling and before the closure. The main body collar 41 has an extension which can be larger than that of the collar 4 of the finished capsule.

Figure 3 shows a lid 3 which - as also the main body 2- is manufactured for example by way of thermoforming or for instance also by way of injection moulding. The lid has an essentially planar central region 31, a transition region 32 which forms an arching, as well as a lid collar 42.

Capsules of the type which are drawn in Figure 1, the main body 2 of the type which is drawn in Figure 2 and the lid 3 of the type which is represented in Fig. 3 are already known from the state of the art, for example from WO 2015/096990.

On manufacture of the capsule, the main body 2 is firstly filled with extraction material, and the lid 3 is subsequently positioned. An ultrasonic welding takes place thereafter, and specifically a torsional welding as is known per se from the state of the art. Optionally, a separation of a protruding collar portion yet takes place subsequently to the welding, depending on the initial extension of the main body collar and the lid collar.

Figure 4 shows an example of a capsule 1 according to the invention. One can recognise that the capsule in the region of the collar 4 at the upper side - thus at the side of the lid collar comprises a plurality of ribs 50 with grooves 51 which are formed therebetween. The ribs 50 run radially with respect to the axis 10. Deviations from the radial direction are also conceivable - for example the ribs 50 could each run parallel to one another and perpendicular to the capsule side wall on each of the four sides. At all events, the alignment of the ribs is not parallel to the circumferential direction (not locally parallel to the side wall, i.e. at an angle with respect to the plane which is defined by the side wall locally at the location of the respective rib), and also not parallel to the course of the collar. In particular, the ribs can each run from the radially inner to the radially outer end of the collar.

The ribs, as are shown in Figure 4, can be arranged relatively close to one another, so that their width and their distances are of a similar magnitude and they form a rib-groove pattern. For example, one can envisage the distance of adjacent ribs (each measured from their centre) not being larger than fourfold or not larger than threefold their width. Arrangements with ribs which are distanced further to one another are however also conceivable.

Figure 5 shows a schematic cross section through the capsule in the region of the collar (the region which is shown dashed in Figure 1). The welding 70 between the main body 2 and the lid 3 is represented schematically by way of a hatching. In Figure 5, one can see that the diffusion barrier layer 70 is essentially intact up to the radially outer end (very left in Fig. 5).

Furthermore, the following optional features but ones which are advantageous for the stable connection between the main body and the lid are represented in Fig. 5:

- The beginning 12 of the arching of the lid is offset radially inwards (offset v) in comparison to the outer side of the circumferential side wall 6. Herein, the offset v is relevant in comparison to the thickness of the capsule wall; in particular it is at least 0.2 mm. The offset v is measured between the planes which in the region of the collar 4 are parallel to the outer surface of the main body and which go through the location of maximal concave curvature in the transition between the lid-side surface and the arching of the lid or the outer surface of the main body.

- The main body forms a thickening 21 in the region of the transition between the circumferential side wall 6 and the main body collar 41, said thickening forming a radially inwardly projecting bead.

- The material thickness of the main body is increased in the region of the main body collar in comparison to the circumferential side wall 6, i.e. the main body collar is thicker than the side wall. This also serves for the stiffening.

Claims

PATENT CLAIMS

1. A portion capsule (1) filled with an extraction material, for production of a brewed product, comprising - a main body (2) of plastic, with a base region (5), a circumferential side wall (6) and a circumferential main body collar (41) which connects to the circumferential side wall towards a lid side; and - a lid (3) of plastic, with a circumferential lid collar (42), wherein the lid is fastened to the main body by way of an inner side of the lid collar being welded to the main body collar, so that a common collar (4) forms, - wherein the main body and the lid enclose the extraction material; - wherein the main body (2) has an essentially rectangular cross section in the region of the collar (4); - wherein the collar (4) comprises a plurality of ribs (50) on an outer side, characterised in that - the ribs (50) run in the collar at the lid side.

2. The portion capsule according to claim 1, wherein the ribs (50) run at an angle with respect to the side wall.

3. The portion capsule according to claim 2, wherein the ribs (50) run radially with respect to an axis (10) which is perpendicular to a plane in which the collar (4) runs.

4. The portion capsule according to one of the preceding claims, wherein the ribs (50) run up to a radially outer end of the collar.

5. The portion capsule according to one of the preceding claims, wherein the lid (3) forms an arching, so that the lid contributes to a capsule volume and a lid face (9) is offset to the collar (4).

6. The portion capsule according to claim 5, wherein the collar comprises a circumferential face (8) which faces the lid side and which extends from an outer edge (7) of the collar (4) to a beginning (12) of the arching, wherein the beginning (12) of the arching is offset inwardly in comparison to a transition between the side wall (6) and the collar (4).

7. The portion capsule according to one of the preceding claims, wherein the lid (3) is manufactured by way of thermoforming.

8. The portion capsule according to one of the preceding claims, wherein the main body (2) is manufactured by way of thermoforming.

9. The portion capsule according to one of the preceding claims, wherein the lid (3) and the main body (2) are manufactured of an identical plastic.

10. The portion capsule according to one of the preceding claims, wherein the lid (3) and/or the main body (2) are manufactured of a biologically degradable plastic.

11. The portion capsule according to one of the preceding claims, wherein the lid (3) and the main body (2) comprise a diffusion barrier layer (70), for example of a PVOH.

12. The portion capsule according to one of the preceding claims, wherein the main body (2) in the region of a transition between the circumferential side wall (6) and the main body collar (41) forms a thickening (21) which forms a radially inwardly projecting bead.

13. The portion capsule according to one of the preceding claims, wherein the number of ribs (50) is at least 20.

14. The portion capsule according to one of the preceding claims, wherein a distance between two adjacent ribs (50) is not more than threefold the average width of the ribs (50).

PCT/EP 2023/050 461 - 14.03.2023

P4978 PCT

1/2 9 3 4 8 1

7 41 2 2

10 6 6

Fig. 1 5

31 3 Fig. 2 42

32 Fig. 3

3

50

1

51 4

6 Fig. 4 ERSATZBLATT (REGEL 26)