Single-serve pack element and single-serve pack

Abstract

A single-serve-pack element (1a; 1b) for forming a wall of the single-serve pack (1) for accommodating an extractable product has at least a first layer made of a first plastics material, and it is substantially free of aluminium particles. The single-serve-pack element (1a; 1b) can also be substantially free of carbon black particles. A single-serve pack (1) has such a single-serve-pack element. It is possible to achieve improved sortability for such single-serve packs (1) and / or single-serve-pack elements (1a; 1b).

Description

[0001] PORTION PACK ELEMENT AND PORTION PACK

[0002] The invention relates to the preparation of beverages or the like from an extraction product, such as ground coffee, contained in a portion pack, for example a portion capsule. It relates to a portion pack for containing the extraction product and its parts, which can in particular be a portion pack cup and a portion pack lid.

[0003] Extraction devices for preparing beverages from a product contained in a portion-sized container are known, for example, as coffee, espresso, or tea machines. In many such systems, the portion-sized containers are designed as capsules (portion capsules) in which the product is sealed, for example, hermetically. For extraction, the capsule is pierced on two opposite sides. A brewing liquid—generally hot water—is introduced into the first side. The brewed product is expelled from the capsule on the second side.

[0004] Among single-serve capsules, capsules are known whose capsule walls consist essentially of plastic. There is a need to recycle such capsules as completely as possible. DE 10 2014109 555 discloses single-serve coffee capsules with a capsule wall made of a plastic material that is free of soot particles, with the capsule wall comprising a white layer. Soot particles are often used to darken capsules, but they lead to the corresponding capsules not being correctly classified in waste sorting facilities. DE 10 2014109 555 teaches that such incorrect classification can be prevented by omitting soot particles and instead providing a white layer in the capsule wall.

[0005] However, it appears that the sortability of the capsules in waste sorting plants still appears to be in need of improvement, even when the capsule wall is truly free of soot particles and the capsule also has a white layer, especially on the inside. Rather, reliable detection in such waste sorting plants also appears to depend on other factors.

[0006] It is an object of the present invention to provide a capsule wall and a capsule with such a capsule wall, which overcomes disadvantages of the prior art and which in particular ensures, enables or facilitates improved reliability in the waste sorting process.

[0007] This problem is solved by the invention as defined in the patent claims.

[0008] According to one aspect of the invention, a portion pack element is provided which serves to form a portion pack wall—that is, a portion pack cup or a portion pack lid. The portion pack element has at least a first layer made of a first plastic material and is characterized by being substantially free of aluminum particles.

[0009] "Substantially free from aluminum particles" means that the proportion (weight percent) of aluminum is not more than 0.08%, i.e., the aluminum content is between 0 and 0.08%. In particular, the proportion (weight percent) of aluminum pigments may be not more than 0.08%, in particular, the mass fraction of aluminum not present in aluminum pigments does not exceed 0.01%. Dyes for coloring portion capsules often contain aluminum pigments, which

[0010] make classification in waste sorting plants more difficult, as explained below.

[0011] The portion pack element may also be completely free of aluminum particles, although possible minimal contamination cannot be ruled out; such contamination, for example, has a weight percentage of no more than 0.01%.

[0012] According to a further aspect of the invention, a portion pack element is provided which serves to form a portion pack wall—that is, a portion pack cup or a portion pack lid. The portion pack element has at least one first layer made of a first plastic material and is characterized by having a weight fraction of aluminum pigments of at most 0.08%; in particular, of at most 0.05%.

[0013] According to a further aspect of the invention, a portion pack element is provided which serves to form a portion pack wall—that is, a portion pack cup or a portion pack lid. The portion pack element has at least one first layer made of a first plastic material and is characterized by having an aluminum content by weight of at most 0.08%; in particular, at most 0.05%.

[0014] A further aspect of the invention relates to the use of a portion pack element which has at least a first layer made of a first plastic material, serves to form a wall of a portion pack for receiving an extraction material, and has a weight fraction of aluminum of at most 0.08%, in particular of at most 0.05%, and / or a weight fraction of aluminum pigments of at most 0.08%, in particular of at most 0.05%, to enable an improvement in reliability in a waste sorting process. In particular, the portion capsule element can comprise aluminum pigments. A further aspect of the invention relates to the use of a portion pack element which has at least a first layer made of a first plastic material, serves to form a wall of a portion pack for receiving an extraction material, and has a weight fraction of aluminum of at most 0.08%, in particular of at most 0.05% and / or a weight fraction of aluminum pigments of at most 0.08%, in particular of at most 0.05%, to enable improved reliability in a waste sorting process. In particular, the portion capsule element can comprise aluminum pigments.

[0015] A further aspect of the invention relates to the use of a portion capsule element comprising at least a first layer made of a first plastic material, serving to form a wall of a portion capsule for receiving an extraction material, and having a weight fraction of aluminum of at most 0.08%, in particular of at most 0.05%, and / or a weight fraction of aluminum pigments of at most 0.08%, in particular of at most 0.05%, to facilitate classification of the portion capsule element in waste sorting plants in which infrared spectroscopy, for example near-infrared spectroscopy, is used to identify various materials, in particular various polymer materials. In particular, the portion capsule element can comprise aluminum pigments.

[0016] A further aspect of the invention relates to the use of a portion capsule element comprising at least a first layer made of a first plastic material, serving to form a wall of a portion capsule for receiving an extraction material, and having a weight fraction of aluminum of at most 0.08%, in particular of at most 0.05%, and / or a weight fraction of aluminum pigments of at most 0.08%, in particular of at most 0.05%, to facilitate classification of the portion capsule element in waste sorting plants in which infrared spectroscopy, for example near-infrared spectroscopy, is used to identify various materials, in particular various polymer materials. In particular, the portion capsule element can comprise aluminum pigments.

[0017] A further aspect of the invention relates to the use of a portion pack element which has at least a first layer made of a first plastic material, serves to form a wall of a portion pack for receiving an extraction material and has a weight fraction of aluminum of at most 0.08%, in particular of at most 0.05% and / or a weight fraction of aluminum pigments of at most 0.08%, in particular of at most 0.05%, to facilitate the achievement of increased reliability of a classification of the portion pack element in a waste sorting process; in particular wherein infrared spectroscopy, for example near-infrared spectroscopy, is used in the waste sorting process to identify different materials, in particular different polymer materials.In particular, the portion pack element may comprise aluminum pigments; and / or the portion pack element has a weight fraction of aluminum pigments of at most 0.08%, in particular of at most 0.05%.

[0018] A further aspect of the invention relates to the use of portion packs for containing an extraction material, wherein the portion packs have at least one portion pack element for forming a wall of a portion pack, which portion pack element has at least one first layer made of a first plastic material and has a weight fraction of aluminum of at most 0.08%, in particular of at most 0.05% and / or has a weight fraction of aluminum pigments of at most 0.08%, in particular of at most 0.05%, to facilitate achieving increased reliability of a classification of the at least one portion pack element in a waste sorting process; in particular wherein infrared spectroscopy, for example near-infrared spectroscopy, is used in the waste sorting process to identify different materials, in particular different polymer materials.

[0019] A further aspect of the invention relates to the use of portion packs for containing an extraction material, wherein the portion packs have at least one portion pack element for forming a wall of a portion pack, which portion pack element has at least one first layer made of a first plastic material and has a weight fraction of aluminum of at most 0.08%, in particular of at most 0.05% and / or has a weight fraction of aluminum pigments of at most 0.08%, in particular of at most 0.05%, to reduce the probability of misclassification of the portion pack element in a waste sorting process; in particular wherein infrared spectroscopy, for example near-infrared spectroscopy, is used in the waste sorting process to identify different materials, in particular different polymer materials.

[0020] The aspects of the invention can be combined with each other.

[0021] Firstly, the invention is based on the new discovery that, in addition to soot particles, aluminum particles, and especially aluminum pigments, can cause inadequate classification in waste sorting plants. The infrared radiation used in waste sorting plants is scattered by aluminum pigments, and this scattering can lead to misclassifications, either by assigning an incorrect material or by failing to assign a material. Misclassifications due to soot particles, on the other hand, arise from the absorption of the infrared radiation used by the soot particles.

[0022] It is a further finding of the invention that the improved classification in waste sorting plants is at least largely independent of the color choice for the capsule element, i.e., a white layer, or in particular an internal white layer, is not necessary to achieve the improved classification. Studies have shown that, with otherwise aluminum-free capsule cups and capsule lids, a fairly reliable classification is achieved by near-infrared spectroscopy up to approximately 0.4 percent by weight of aluminum pigments in the colorants of the capsule cup or capsule lid, with the weight proportion of the colorants in the capsule cup or capsule lid ("dosage") being between 4% and 22%, in particular between 6% and 18%; for example, for lids, between 6% and 18%, and for cups, between 11% and 17%.

[0023] The portion pack can be a portion capsule.

[0024] In embodiments, the portion pack element has the wall, i.e. a portion pack wall.

[0025] In embodiments, the portion pack element is a portion pack cup.

[0026] In other embodiments, the portion pack element is a portion pack lid. The portion pack lid can, in particular, be dimensionally stable and is therefore not a film, such as some portion packs use to close the portion pack cup.

[0027] In some embodiments, the portion pack element is essentially free of soot particles. This prevents misclassifications particularly well and enables particularly reliable classification.

[0028] "Substantially free of soot particles" means that the proportion (mass percent) of soot particles is 0.08% or less, i.e., the soot particle content is between 0 and 0.08%. Even soot particle contents as low as approximately 0.01% by weight can make detection difficult. The portion pack element can also be completely free of soot particles—although possible minimal contamination cannot be ruled out in each case; such contamination, for example, has a mass fraction of no more than 0.002%. In embodiments, the first layer is essentially free of aluminum particles.

[0029] In embodiments, the first layer forms an outer layer of the portion pack element. The first layer can thus form an outer layer and / or an inner layer of the portion pack. In particular, the first layer can form an outer layer of the portion pack. Therefore, if the first layer comprises aluminum or, in particular, aluminum pigments, their weight fraction must be correspondingly low if it is to be substantially free of aluminum particles.

[0030] In embodiments, the portion pack element comprises aluminum pigments, particularly in the first layer. In particular, the aluminum pigments in the first layer can constitute a weight fraction of the portion pack element of at most 0.08%, particularly at most 0.05%.

[0031] In embodiments, the first plastic material comprises polypropylene. Due to its mechanical and thermal properties, polypropylene is ideal for the production of coffee capsule components (such as capsule cups and capsule lids). Polypropylene can generally be easily identified in waste sorting facilities using infrared spectroscopy.

[0032] In particular, the first plastic material can consist of at least 60 percent by weight, especially at least 70 percent by weight, polypropylene. It can in particular consist of at least 80 percent by weight or even at least 90 percent by weight, polypropylene.

[0033] For example, the portion pack element can consist of between 60 and 80 percent polypropylene by weight. The same can also apply to the portion pack. The portion pack element can also have one or more additional layers in addition to the first layer, for example, at least one layer of biodegradable material.

[0034] In embodiments, the portion pack element comprises a second layer made of a second plastic material, in particular wherein the second plastic material is a biodegradable material. In particular, the second layer can be adjacent to the first layer or connected to the first layer via a further, intermediate layer.

[0035] The second plastic material can in particular contain a polyvinyl alcohol copolymer, in particular a polyvinyl alcohol (PVOH), an ethylene-vinyl alcohol copolymer (EVOH), or a butenediol-vinyl alcohol copolymer (BVOH). These plastic materials can form an oxygen barrier, which is of great importance for the quality and storage life of sensitive extraction materials such as coffee powder. Furthermore, these plastic materials are water-soluble, which contributes to their environmental friendliness. The second plastic material can, for example, contain at least 50% by weight, in particular at least 70% by weight, of a polyvinyl alcohol copolymer, for example one of the aforementioned (PVOH, EVOH, BVOH) or a mixture of at least two thereof. In other embodiments, the second plastic material contains between 1 and 5% by weight of such a polyvinyl alcohol copolymer.

[0036] In embodiments, the portion pack element contains between 1 and 5 percent by weight of such a polyvinyl alcohol copolymer. The same can also apply to the portion pack. Embodiments of the invention are described below with reference to drawings. In the drawings, like reference numerals designate like or analogous elements. They show:

[0037] Fig. 1 shows a portion pack designed as a capsule in a side view;

[0038] Fig. 2 a portion pack cup of the capsule according to Fig. 1, in perspective view;

[0039] Fig. 3 a portion pack lid of the capsule according to Fig. 1, in perspective view;

[0040] Figs. 4a to 6b classification images;

[0041] Fig. 7 shows the gray levels used for classification result coding.

[0042] Parts not essential to understanding the invention are partly omitted. The described embodiments are exemplary of the subject matter of the invention or serve to explain it and are not limiting.

[0043] The portion pack designed as a capsule 1 according to Figure 1 essentially has the shape of a cube with rounded edges. However, its dimensions increase slightly toward the top, so that, strictly mathematically speaking, the capsule has a truncated pyramid shape. The angle of inclination of the lateral surfaces in the figure relative to the perpendicular (dashed line in Figure 1) to the base is very small, preferably no more than 2°, for example, only approximately 1°. Furthermore, the height of the capsule above the base approximately corresponds to the length of the base edges.

[0044] The capsule 1 comprises a portion pack cup (or capsule cup) 1b and a portion pack lid (or capsule lid) 1a attached thereto along a circumferential collar. The capsule cup forms a capsule base and a circumferential side wall, which is closed off by the collar at its outer end (upper end in the figure) in relation to axial directions (parallel to the axis shown as a dashed line in Fig. 1). The capsule lid 1a is curved outwards in that the lid surface, which is essentially parallel to the capsule base, is offset outwards (and axially 'vertically') compared to the circumferential collar, i.e., upwards in Fig. 1.

[0045] The capsule 1 is filled with an extraction material, for example coffee powder (not shown in Fig. 1).

[0046] Figure 2 shows the capsule cup 1b before filling and before closing. The capsule cup collar has an extension that may be larger than that of the collar of the finished capsule.

[0047] Figure 3 shows a capsule lid 1a, which—like the capsule cup 1b—is manufactured, for example, by injection molding. The capsule lid 1a has a lid surface in a central region, a transition region forming a curvature, and a lid collar.

[0048] Capsules 1 of the type shown in Figure 1, capsule cups 1b of the type shown in Figure 2 and capsule lids 1a of the type shown in Figure 3 are already known from the prior art, for example from WO 2015 / 096990.

[0049] However, the portion packaging and portion packaging elements or portion packs (in particular capsules) and portion packaging elements (in particular capsule elements) described here are essentially free of aluminum particles.

[0050] During capsule production, a capsule element (capsule cup 1b) is first filled with the extraction material, and then another capsule element (capsule lid 1a) is positioned. Ultrasonic welding then takes place to seal the capsule airtight. Depending on the initial expansion of the capsule cup collar and the capsule lid collar, an optional trimming of the excess collar section may be performed after welding.

[0051] Because capsule elements are essentially free of aluminum particles, infrared light shone onto them is less scattered. This facilitates classification of the capsule elements in waste sorting facilities, where infrared spectroscopy, such as near-infrared spectroscopy, is used to identify different materials, particularly different polymer materials. For example, the capsule elements may have a polypropylene layer that can be identified in this way.

[0052] To be essentially free of aluminum particles, the capsule elements are either completely free of aluminum particles (except for unavoidable minor aluminum-containing contamination). Or they contain aluminum pigments, particularly in the polypropylene layer, but only in very small quantities. For example, the aluminum pigments each make up only 0.08% by weight of a capsule element.

[0053] Furthermore, the capsule elements are free of soot particles, which absorb infrared light and thus lead to misclassifications.

[0054] The effect that the classification based on infrared spectroscopy depends strongly on the content of aluminum particles was verified in experiments.

[0055] Figures 4a to 6b show corresponding experimentally obtained classification images. The pattern fills used to encode the classification results are shown in Figure 7: The two hatchings correspond to a correct classification (polypropylene was identified), the dot fills are misclassifications to other plastics (PET or PA-6), and for black areas, the near-IR spectroscopy measurement results could not be assigned to a specific plastic. In each experiment, a collection of portion pack elements in a waste sorting facility was examined using near-infrared spectroscopy; capsule cups in Figures 4a to 5b, capsule cups in Figures 6a and 6b.

[0056] The portion pack elements contained a dye in a polypropylene layer. The polypropylene layer formed an outer layer of the respective portion pack element.

[0057] The portion pack elements were free of soot particles.

[0058] In Fig. 4a, the dye contained a weight fraction of 0.3% of aluminum pigments, in Fig. 4b, with otherwise identical properties, a weight fraction of 0.65% of aluminum pigments.

[0059] In Fig. 5a, the dye contained a weight fraction of 0.27% of aluminum pigments, in Fig. 5b, with otherwise identical properties, a weight fraction of 0.83% of aluminum pigments.

[0060] In Fig. 6a, the dye contained 0% by weight of aluminum pigments, while in Fig. 6b, with otherwise identical properties, it contained 2.1% by weight of aluminum pigments.

[0061] The weight proportion of the dye in the respective portion pack element was approximately 14% (dosage in the case of the capsule cups) or between 12% and 14% (dosage in the case of the capsule lids).

[0062] As Figs. 4a to 6b clearly show, with the lower weight fraction of aluminum pigments (Figs. 4a, 5a, 6a) there is a large proportion of correct classifications (hatched), while with the higher weight fraction of aluminum pigments (Figs. 4b, 5b, 6b) there is a large proportion of misclassifications (dotted or black), namely either by assignment to another plastic (dotted) or because no plastic could be assigned (black).

[0063] From the experiments it can be concluded that it is advantageous to have a

[0064] The weight proportion of aluminium pigments in the dye should not exceed approximately 0.4% in order to achieve sufficiently good classifiability in a waste sorting plant.

[0065] From classification images such as those shown in Figs. 4a to 6b, a so-called valve mirror can be created, on the basis of which valves in the waste sorting plant can be controlled in such a way that material located where the classification result is polypropylene can be separated out by means of an air blast.

Claims

PATENT CLAIMS 1. Portion packaging element for forming a wall of a portion packaging for receiving an extraction material, comprising at least a first layer made of a first plastic material, wherein the portion packaging element is substantially free of aluminum particles.

2. Portion packaging element according to claim 1, which has a weight fraction of aluminum of at most 0.08%, in particular of at most 0.05%.

3. Portion packing element according to claim 1 or claim 2, which has a weight fraction of aluminum pigments of at most 0.08%, in particular of at most 0.05%.

4. Portion packing element according to one of claims 1 to 3, which is substantially free of soot particles.

5. Portion pack element according to one of claims 1 to 4, wherein the first layer forms an outer layer of the portion pack element.

6. Portion packing element according to one of claims 1 to 5, wherein the first plastic material comprises polypropylene, in particular wherein the first Plastic material consists of at least 60 percent by weight, in particular at least 80 percent by weight, of polypropylene.

7. Portion pack element according to one of claims 1 to 6, comprising a second layer consisting of a second plastic material, wherein the second plastic material contains a polyvinyl alcohol copolymer, in particular at least 50% by weight.

8. Portion pack comprising a portion pack element according to one of claims 1 to 7, wherein the portion pack element is a capsule cup or a Capsule lid is.

9. Portion pack according to claim 8, containing an extraction material, in particular coffee powder, which is packaged airtight in the portion pack.

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