EP3348494A1 - Capsule for preparing a beverage - Google Patents

Abstract

Proposed is a capsule (1) for the preparation of a beverage. Said capsule (1) comprises a preferably rotationally symmetrical capsule body (2) with a side wall (3) and a bottom (4), in particular integrally formed therewith. In addition, the capsule (1) comprises a lid (16) covering the capsule body (2) to form a closed chamber (9) which contains at least one starting substance for the preparation of the beverage. The capsule body (2) has at least one, in particular slit-shaped, opening (11) or predetermined breaking line (5, 5 ') for passing a liquid through the capsule (1). The capsule body (2) is at least partially coated with a barrier layer (12) covering the opening (11) or the predetermined breaking line (5, 5 ') of a metal oxide.

Description

The present invention relates to a capsule for the preparation of a beverage according to the preamble of claim 1.

The prior art discloses a variety of different portion packages and systems for making beverages. In particular, capsules are often used for the production of different hot drinks, especially coffee or tea, in home use. Usually, such capsules, which are designed as disposable products, comprise a capsule body for holding the beverage ingredients and a lid covering the capsule body. The ingredients are mostly roasted and ground coffee beans, but sometimes also dried tea leaves. However, soluble products in general or concentrates are also suitable. In the actual preparation, pressurized water is passed through the capsule, resulting in extraction or dissolution of the material contained in the chamber.

That's how it describes WO 2013/092910 A1 a capsule for the production of beverage products. The capsule comprises a lidded capsule body for forming a closed chamber containing a substance for making a beverage. The capsule body has in the region of the bottom slots for the passage of a liquid through the capsule. These have the function of facilitating a penetration of the capsule base with a device provided for this purpose. Preferably, the capsule body is produced by means of a deep-drawing process.

By attaching slots on the capsule bottom results in the disadvantage that the capsule body is not fluid-tight per se. To take this into account, it is proposed that the slots with a to close substantially air-impermeable layer. This may be, for example, a soluble and food-grade polymer or else an aluminum foil which is also penetrated. However, the attachment of such a layer in or on the capsule body is expensive and expensive.

Furthermore, the production of a deep-drawn capsule body made of a plastic material is more expensive than a corresponding injection molding and allows less complex shapes. In order to carry out such a capsule body oxygen and / or aroma-impermeable, this must usually be made of a multilayer composite material of different plastics. This makes it difficult to recycle the capsule after use.

The EP 2 957 524 A1 describes a capsule for the preparation of a beverage whose capsule body has a bottom with a weakening pattern with at least one predetermined breaking line. The capsule body is designed such that it comes at a predetermined external pressure on the ground to a tearing of the capsule body along the predetermined breaking line. This makes it possible to open the capsule in a beverage preparation device intended for this purpose, without the need for penetrating agents.

However, the said capsule has the disadvantage that the capsule body in the region of the predetermined breaking line has only a very small wall thickness and is therefore not oxygen and / or aroma-tight. As a result, a starting substance contained in the capsule can not be stored therein for an extended period of time.

It is an object of the present invention to overcome the above-mentioned disadvantages of the prior art. Especially It is an object of the present invention to provide a capsule which can be used in many different ways and is structurally simple for closed, in particular oxygen and / or aroma-tight, intake of at least one starting substance for preparing a beverage. Nevertheless, the capsule should be able to be easily opened as part of a beverage production. In addition, the capsule should be inexpensive and can be produced in large quantities.

These objects are achieved by a capsule having the features in claim 1. The capsule for the preparation of a beverage comprises a preferably rotationally symmetrical capsule body having a side wall and a bottom in particular integrally formed therewith. Furthermore, the capsule comprises a capsule body covering the lid to form a closed chamber. The chamber contains at least one starting substance for the preparation of the beverage. The capsule body has at least one, in particular gap-shaped, opening or predetermined breaking line for passing a liquid through the capsule. The capsule body is at least partially coated with a barrier layer covering the opening or the predetermined breaking line from a metal oxide.

The term metal oxide in the present context not only oxides of metals understood, but also oxides of the semi-metal silicon.

This embodiment of the capsule allows a particularly reliable closed recording of at least one starting substance for the preparation of a beverage, although the capsule body has at least one opening or predetermined breaking line for passing a liquid through the capsule. As part of a beverage production, the capsule can thus be easily opened. The Capsule is inexpensive and can be produced in large quantities, since in particular an expensive attachment of an aluminum foil in the region of an opening or predetermined breaking line is eliminated.

The capsule body may be oxygen and / or aroma-tight. By an oxygen-tight embodiment, penetration of oxygen into the capsule during storage of a starting substance contained therein can be substantially avoided. Accordingly, aging of the starting substance, for example coffee grounds, can be avoided by oxidation. An oxygen-tight capsule is usually also aroma-tight. Accordingly, leakage of flavors contained in the starting substance during storage thereof within the capsule is substantially prevented.

Oxygen and / or aroma resistance is required to achieve a minimum shelf life of 12 months, preferably 18 months, especially for coffee. Accordingly, in the present context, an oxygen-tight and / or aroma-tight capsule is understood as meaning a capsule in which coffee powder can be stored at atmospheric temperature for at least 12 months, preferably at least 18 months, without the coffee powder changing which significantly compromises the quality of a coffee beverage produced therefrom.

The capsule body may have a surface-adjusted oxygen transmission rate (OTR) in the unit cm ³ per m ² per day per 0.21 bar of less than 20, preferably less than 10, preferably less than 5. The OTR indicates the amount of oxygen diffused per unit area and time through the capsule body.

The capsule body can be made of a plastic material, in particular of polypropylene or of a biodegradable plastic material. A capsule body of these materials is more environmentally friendly than, for example, one made of aluminum. Thus, a capsule body made of a plastic material can be supplied for thermal recycling. However, an actual recycling or possibly a biological degradation is possible. In particular, in this context, a barrier layer of a metal oxide has the advantage that it can be made comparatively thin, as will be explained in more detail below. This makes it possible to provide a capsule with a capsule body which is essentially made of a single plastic material (a so-called mono material). This has the advantage over multilayer capsule bodies that a capsule according to the invention can be recycled more easily in a more environmentally friendly manner or, if appropriate, degraded. Polypropylene has proven itself in beverage packages, especially for portion packaging of hot drinks. It can be perfectly processed by injection molding, coated with a metal oxide and sealed. In addition, it is easy to recycle.

The barrier layer may consist of a silicon oxide or of an aluminum oxide. These two materials show good barrier properties, especially with regard to the oxygen and / or aroma resistance. In addition, such barrier layers are largely insensitive to heat and moisture, which also sterilization and pasteurisationstaugliche capsules can be produced.

The barrier layer may have a thickness of 10 nm to 1 μm, preferably from 20 nm to 500 nm, preferably from 40 nm to 200 nm. Such low layer thicknesses have the advantage that for coating the capsule body only a small Amount of metal oxide must be used. This results in the advantage already explained above that a capsule coated with such a thin barrier layer can possibly be regarded as consisting of a monomaterial. Furthermore, such thin barrier layers are substantially transparent. This capsule body of any color can be coated without them being no longer visible. The production of transparent capsule body is possible.

If the capsule body has a slit-shaped opening, this may have a width of less than 150 nm, preferably less than 100 nm, preferably less than 50 nm. Such narrow gap-shaped openings can be covered particularly well with a barrier layer of a metal oxide. Such openings can be attached to the capsule body with a laser cutting method.

The capsule body may be made by an injection molding or a deep drawing process. In particular, an injection molding process has the advantage that capsule bodies of virtually any geometry can thus be produced inexpensively in large quantities. As a rule, injection-molded parts consist of a mono-material that can be easily and inexpensively recycled in an environmentally friendly way. Due to the barrier layer of a metal oxide, the capsule body consisting of a monomaterial nevertheless has a high oxygen and / or aroma resistance.

In particular, for the production of a capsule body with at least one predetermined breaking line, the use of an injection molding method is advantageous, since by means of injection molding particularly effective wall and / or floor areas can be produced with reduced thickness. Opposite capsule bodies with at least In addition, an opening in this context has proved to be favorable in that, in the production of capsule bodies with at least one predetermined breaking line, the two halves of the injection mold do not have to come into contact in order to produce an opening in the casting (capsule body). As a result, excessive wear of the injection mold can be avoided.

The barrier layer can be applied to the capsule body by a plasma coating process, preferably by a PEVCD process. For the PEVCD (Plasma Enhanced Chemical Vapor Deposition) method, HMDSO (hexamethyldisiloxane) or TEOS (tetraethoxysilane) is preferably used. Particularly preferred may be a plasma pretreatment with HMDSO and / or TEOS and oxygen (O ₂ ). As a result, capsule bodies can be coated with comparatively complex geometry. In addition, this method can be applied to a very thin barrier layer described above.

The barrier layer may be attached to the inside, outside or both sides of the capsule body. This provides great flexibility in the design of the capsule body. In particular, when the barrier layer is attached to the inside of the capsule body, it is possible to prevent substances contained in the at least one starting substance for the preparation of a beverage from diffusing into the material of the capsule body.

The capsule body can additionally, on the inside, on the outside or on both sides, have an overcoat layer. This overcoat layer may in particular have a thickness of 500 nm to 50 μm, preferably from 1 μm to 25 μm, preferably from 2 μm to 10 μm. The said overcoat layer can make the optical appearance of the capsule more appealing. However, she can also serve to protect the barrier layer against abrasion and / or corrosion.

The gap-shaped opening or the predetermined breaking line can be formed after its rupture as a bottleneck for foaming a liquid derived from the capsule body. This is particularly advantageous in the production of cafe cream or espresso to achieve the characteristic crema, but also for the production of milk foam.

Further advantages and individual features of the present invention will become apparent from the following description of several embodiments and from the drawings.

Figur 1:

Perspektivische Darstellung eines Kapselkörpers einer erfindungsgemässen Kapsel mit Sollbruchlinien;

Figur 2:

Schnittansicht eines Kapselkörpers gemäss Figur 1;

Figur 3:

Vereinfachte Vergrösserung des Teilbereichs A aus Figur 2;

Figur 4:

Perspektivische Darstellung einer erfindungsgemässen Kapsel mit einem Kapselkörper gemäss den Figuren 1 bis 3;

Figur 5:

Seitenansicht eines Kapselkörpers eines alternativen Ausführungsbeispiels einer erfindungsgemässen Kapsel mit spaltförmigen Öffnungen;

Figur 6:

Draufsicht auf einen Kapselkörper gemäss Figur 5;

Figur 7:

Vereinfachte Vergrösserung des Teilbereichs B aus Figur 5;

Figur 8:

Schnittansicht eines Kapselkörpers eines weiteren einer erfindungsgemässen Kapsel;

Figur 9:

Vereinfachte Vergrösserung des Teilbereichs C aus Figur 8.

They show schematically:

FIG. 1:

Perspective view of a capsule body of a capsule according to the invention with predetermined breaking lines;

FIG. 2:

Sectional view of a capsule body according to FIG. 1 ;

FIG. 3:

Simplified enlargement of the portion A of Figure 2;

FIG. 4:

Perspective view of a capsule according to the invention with a capsule body according to FIGS FIGS. 1 to 3 ;

FIG. 5:

Side view of a capsule body of an alternative embodiment of a capsule according to the invention with slit-shaped openings;

FIG. 6:

Top view of a capsule body according to FIG. 5 ;

FIG. 7:

Simplified enlargement of the portion B of Figure 5;

FIG. 8:

Section view of a capsule body of another of a capsule according to the invention;

FIG. 9:

Simplified enlargement of the subregion C from FIG. 8.

FIG. 1 shows a capsule body 2 of a first embodiment of a capsule according to the invention 1. The capsule body 2 is rotationally symmetrical with respect to its longitudinal central axis L and comprises a side wall 3 and an integrally connected with this bottom 4. In the region of the bottom 4, the capsule body 2 predetermined breaking lines 5, 5 ' on. The capsule body 2 is produced in one piece by an injection molding process and consists of a plastic suitable for injection molding, for example polypropylene or polyethylene. The capsule body 2 is coated on the inside with a barrier layer 12 of silicon oxide, which is applied by a plasma coating process (see. Fig. 3 ). The predetermined breaking lines 5, 5 'in the region of the bottom 4 are arranged in a cross-shaped pattern. In addition to the predetermined breaking lines 5, 5 ', the bottom 4 also has the weakening lines 6, 7 and 8.

How out FIG. 2 shows, the capsule body 2 forms a chamber 9 for receiving at least one starting substance for the preparation of a beverage. These may be, for example, roast and ground coffee beans, dried tea leaves, dried milk or chocolate powder. However, other starting substances for the preparation of drinks would also be conceivable, for example concentrates for lemonades. Within the Chamber 9 4 support elements 10 are arranged on the side wall 3 and in the transition region to the bottom. These each support a section of the base 4 located between two parallel predetermined breaking lines 5, 5 '. In the partial enlargement A according to FIG FIG. 3 the design of the predetermined breaking lines 5, 5 'can be seen better. In addition, the barrier layer 12 is indicated on the inside of the capsule body by a thick black line. The thickness of the line does not reflect the thickness of the barrier layer 12 to scale. The barrier layer 12 ensures that the capsule body is also oxygen-tight and / or aroma-tight in areas with reduced wall thickness.

In FIG. 4 the capsule 1 is shown after it has been opened by pressing the bottom 4. It can be seen that the regions of the bottom 4 lying between two predetermined breaking lines 5, 5 'were supported by the supporting elements 10, while the arched bottom 4 was pressed in.

The FIGS. 5 to 7 show a capsule body 2 for an alternative embodiment of a capsule according to the invention 1. The said capsule body 2 is made by a deep-drawing process and consists of a side wall 3 and an integrally formed with this bottom 4. The capsule body 2 is on the inside with a barrier layer 12 of silicon oxide coated, which is applied by a plasma coating method. In the area of the bottom 4, the slots 11 are attached. As from the partial enlargement B according to FIG. 7 The thickness of the line does not reflect the thickness of the barrier layer 12 to scale. Also the width of the in FIG. 7 Slit shown is not true to scale. The capsule body is so oxygen and / or aroma-tight, but can still easily in a designated beverage production device penetrate. Since the tightness of the capsule body 2 is achieved by the barrier layer 12, this can be made of a monomaterial by deep drawing. Since the thickness of the barrier layer 12 is comparatively small compared to the wall thickness of the capsule body, the capsule body can be easily recycled, in fact as a monomaterial.

How out FIG. 8 As can be seen, a further embodiment of a capsule 1 according to the invention comprises a capsule body 2 which is closed by a lid (not shown). On the opposite side of the lid of the capsule 1, a discharge nozzle 13 is arranged. The capsule body 2 has a chamber 9, in which a starting substance for the preparation of a beverage can be stored. Between the chamber 9 and the outlet pipe 13, a filter element 14 is arranged, which prevents leakage of undissolved substance particles from the capsule 1. Subsequent to the filter element 14 is followed by a collecting space 15, which collects the prepared beverage in an area above the outlet 13.

As in particular from the partial enlargement C according to FIG. 9 closer, it is found in the outlet 13 a predetermined breaking line 5 is arranged. On the inside of the capsule body 2, a barrier layer 12 is applied, which covers the predetermined breaking line 5. The thickness of the line does not reflect the thickness of the barrier layer 12 to scale. The barrier layer 12 ensures that the capsule body is also oxygen-tight and / or aroma-tight in areas with reduced wall thickness. The gap-shaped opening, which forms after tearing open the predetermined breaking line, is designed as a constriction for foaming a fluid derived from the capsule body. The capsule shown can thus be used to make Cafe Creme or Espresso with the characteristic crema.

Claims (12)

Capsule (1) for preparing a beverage, comprising a preferably rotationally symmetrical capsule body (2) with a side wall (3) and with a bottom (4), in particular integrally formed therewith, and with a lid (16) covering the capsule body (2) for forming a closed chamber (9) containing at least one starting substance for preparing the beverage, wherein the capsule body (2) at least one, in particular slit-shaped, opening (11) or predetermined breaking line (5, 5 ') for passing a liquid through the capsule (1), characterized in that the capsule body (2) at least partially with a the opening (11) or the predetermined breaking line (5, 5 ') covering the barrier layer (12) is coated from a metal oxide. Capsule (1) according to claim 1, wherein the capsule body (2) is oxygen and / or aroma-tight. Capsule (1) according to one of claims 1 or 2, wherein the capsule body has a surface-adjusted oxygen transmission rate (OTR) in the unit cm ³ per m ² per day per 0.21 bar of less than 20, preferably less than 10, preferably less than 5, has. Capsule (1) according to one of claims 1 to 3, wherein the capsule body (2) consists of a plastic material, in particular of polypropylene. Capsule (1) according to one of claims 1 to 4, wherein the barrier layer (12) consists of silicon oxide or aluminum oxide. Capsule (1) according to one of claims 1 to 5, wherein the barrier layer (12) has a thickness of 10 nm to 1 μm, preferably from 20 nm to 500 nm, preferably from 40 nm to 200 nm. Capsule (1) according to one of claims 1 to 6, wherein the capsule body (2) has a slit-shaped opening (11) with a width of less than 150 nm, preferably less than 100 nm, preferably less than 50 nm. Capsule (1) according to one of claims 1 to 7, wherein the capsule body (2) is produced by an injection-molding or deep-drawing process. Capsule (1) according to one of claims 1 to 8, wherein the barrier layer (12) by a Plasmabeschichtngsverfahren, preferably by a PEVCD method, on the capsule body (2) is applied. Capsule (1) according to one of claims 1 to 9, wherein the barrier layer (12) on the inside, outside or on both sides of the capsule body (2) is applied. Capsule (1) according to one of claims 1 to 10, wherein the capsule body in addition, inside, outside or both sides, a topcoat layer, wherein the overcoat layer in particular has a thickness of 500 nm to 50 .mu.m, preferably from 1 .mu.m to 25 .mu.m, preferably from 2 microns to 10 microns, has. Capsule (1) according to one of claims 1 to 11, wherein the gap-shaped opening (11) or the predetermined breaking line (5, 5 ') according to the cracks as a bottleneck for foaming a derived from the capsule body liquid is formed.

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