DETERGENT CAPSULE AND METHOD FOR ITS MANUFACTURE

Description

[0001] The invention relates to a detergent capsule with an outer shell based on a water-soluble plastic film, which encloses at least one inner receiving space in which detergent or detergent components or laundry care products are contained.

[0002] For the purposes of this invention, the term "detergent" encompasses any washing and cleaning agent compositions suitable for use in a washing machine and / or a dishwasher. Laundry care products are also included in the definition of detergents. Laundry care products include, for example, fabric softeners or fragrance formulations, which may be free or nearly free of washing-active substances such as surfactants, but which fragrance or condition the laundry.

[0003] Detergents in solid, powdered, and / or liquid form for use in washing machines and dishwashers are now widely available in pre-measured portions, which, according to the invention, are referred to as detergent capsules. These detergent capsules are made particularly user-friendly by a water-soluble outer shell made of plastic film, which allows a single dose of detergent to be added directly to the machine. The water-soluble outer shell dissolves in the wash water, releasing the detergent. This avoids direct contact with the detergent, which is considered a significant advantage. Such detergent capsules are described, for example, in DE 10 2014 014 767 A1.

[0004] In addition to single-chamber systems, in which a single dose of detergent is enclosed in a single receiving chamber formed by the outer shell, multi-chamber systems are also known, for example, from DE 10 2015 204 170 A1 and WO 02 / 085736 A1, in which the outer shell has several separate receiving chambers, each filled with a portion of the detergent dose. It is possible for all receiving chambers of the detergent capsule designed as a multi-chamber system to be filled with the same detergent composition, but it is also possible for different components of the detergent to be enclosed in different receiving chambers.

[0005] WO 2014 / 202412 A1 discloses a water-soluble multi-chamber capsule thermoformed from two layers of a water-soluble film, the capsule comprising at least two chambers with a different part of a detergent composition in each chamber.

[0006] Laundry detergent capsules of the type described above represent a growing market. To achieve a desired level of effectiveness, the amount of detergent or its individual components contained in a single capsule can vary, for example, 25 g for premium products, 22 g for mid-range products, and 20 g for particularly inexpensive products. However, even the lower dosages can be sufficient, depending on market demands, washing conditions, and consumer expectations. A lower detergent dosage within a single capsule is therefore desirable from both an economic and an environmental perspective.

[0007] On the other hand, a minimum size for such detergent capsules is required for reasons of ease of handling and product safety. For example, detergent capsules that are too small can be difficult for elderly people or people with limited motor skills to handle. Furthermore, excessively small detergent capsules pose the risk of being swallowed accidentally, for example by children, or becoming lodged in the throat. Safety experts therefore demand a minimum size and volume for detergent capsules to effectively counter this risk.In addition, there is the problem that the surface of the usually water-soluble outer shell becomes sticky upon contact with liquids, which poses a further health risk if ingested orally and further reinforces the requirement for a minimum size and volume of the detergent capsules in order to counter the aforementioned dangers in the event of improper use.

[0008] If, taking into account the required minimum size and minimum volume, the economically desirable lower detergent dosage is to be maintained within a single detergent capsule, essentially two options are currently available.

[0009] On the one hand, a standard detergent capsule that meets the required minimum size and volume can be filled with a smaller dose of detergent or detergent components. However, due to the capsule's disproportionately large volume and size, this results in a correspondingly large air bubble in the remaining free space. Even if the weight declaration on the packaging and the actual fill quantity are correctly stated, such large air bubbles in the detergent capsule create a negative impression for the consumer, as they suggest an insufficient fill level.

[0010] On the other hand, the overall dimensions of the detergent capsule can be altered, resulting in a larger surface area with a relatively flat capsule. While such flat, large-surface detergent capsules prevent the risk of accidental ingestion, they are not as readily accepted by consumers.

[0011] The object of the invention is to propose a detergent capsule of the type mentioned above and a method for its production, which, even with reduced dosage of the detergent or detergent components taken up in the receiving space, has a spatial extent similar to that of the detergent capsules established on the market to date, while preventing excessive formation of air bubbles in the receiving space, and which should be capable of being produced using existing equipment with minimal effort.

[0012] To solve the problem posed, the invention proposes the design of a detergent capsule according to the features of claim 1.

[0013] Advantageous embodiments and further developments of the invention are the subject of the dependent claims.

[0014] The solution according to the invention provides that at least one receiving chamber of the detergent capsule has at least one partially incorporated sealing seam that partially, but not completely, divides the receiving chamber. This internal sealing seam is designed such that it is either non-contacting with a circumferential rim that defines the receiving chamber and preferably has a substantially constant width, or that contact with this circumferential rim does not create a closed volume in the form of an additional chamber. A single contact between the incorporated sealing seam and this circumferential rim is therefore possible. In this case, the internal sealing seam would extend from the circumferential rim into the interior of the receiving chamber.

[0015] It was surprisingly discovered that by simply manipulating the usual capsule shape and the corresponding mold cavities, detergent capsules can be produced that have a significantly reduced filling volume, but still have sufficient size and overall volume to meet the requirements for ease of handling and product safety.

[0016] Furthermore, the detergent capsules designed according to the invention have a shape that is perceived by the consumer as appealing and modern, resulting in a correspondingly good market acceptance.

[0017] If the detergent capsule according to the invention has only a single inner receiving space, which is also referred to as a mono-pouch, this receiving space is provided according to the invention with at least one sealing seam introduced in a partial area.

[0018] Alternatively, if the detergent capsule according to the invention has several, for example two to four, such discrete, i.e. separate, receiving spaces, one, several or all receiving spaces can each be provided with at least one sealing seam according to the invention.

[0019] A preferred embodiment of a detergent capsule according to the invention comprises only a receiving chamber with a sealing seam partially incorporated.

[0020] The sealing seam introduced according to the invention only partially subdivides the receiving space, i.e., not completely, which would result in a subdivision into further receiving spaces, but only to the extent that the volume of the originally existing receiving space is restricted, but all areas of the receiving space still communicate with each other and jointly serve to receive the intended detergent or detergent component.

[0021] According to one aspect of the invention, the sealing seam can project from the circumference of the outer casing into the receiving space and is thus partially surrounded by the receiving space, which surrounds the sealing seam in a C, S, Z, or U shape. The detergent or detergent component filled into the receiving space is arranged accordingly.

[0022] According to an alternative proposal of the invention, the sealing seam is completely surrounded by the receiving space, which then extends in a ring-shaped manner around the preferably centrally placed sealing seam when viewed from above, and the detergent or detergent component filled into the receiving space is also arranged accordingly.

[0023] The essential point is that the sealing seam reduces the originally existing volume of the receiving space of the detergent capsule according to the invention, which is in itself too large for the dosed detergent or detergent component, in the area of ​​the sealing seam to such an extent that an air bubble in the receiving space is minimized or ideally completely eliminated.

[0024] According to a further aspect of the invention, the outer shell of the detergent capsule according to the invention can be formed from two layers of film joined together at the edges and in the area of ​​the at least one sealing seam. The connection can be achieved, for example, by compression and / or welding.

[0025] As mentioned at the outset, the plastic film used to form the outer shell is preferably water-soluble, for example, by being based on polyvinyl alcohol (PVA). The films used generally consist of polyvinyl alcohol copolymers with appropriate additives such as plasticizers, surfactants, bittering agents, or salts.

[0026] Such a plastic film can be manufactured, for example, using solvent casting or blown extrusion processes. The plastic film can also be single-layered or multi-layered, for example, two-layered. Optionally, the film can be printed or decorated on the inside or outside, for example with consumer information and pictograms. The printing can be multi-colored, and water-soluble or water-insoluble inks can be used.

[0027] The design and dimensions of the at least one sealing seam of the detergent capsule provided according to the invention are not subject to any general restrictions and can be determined by a person skilled in the art according to the objectives to be met. However, for the purposes of the invention, it is considered advantageous if the sealing seam has a width of approximately 0.5–5 mm, preferably 1–5 mm, more preferably 0.5–3 mm, or even more than 5 mm or more than 1 cm. The sealing seam can be straight, for example, in the form of a dividing strip, or it can be of any freeform shape. For example, the sealing seam can be U-shaped, V-shaped, triangular, or circular. For example, this freeform shape can have dimensions of up to 25 x 25 mm, or in the case of a circular shape, a diameter of up to 25 mm, or preferably dimensions of up to 10 x 10 mm, or in the case of a circular shape, up to 10 mm. Larger or elongated sealing seams are also conceivable.In any case, the sealing seam does not enclose a cavity filled with detergent, but is only surrounded by one.

[0028] The following table illustrates an advantage of the present invention. A prior art detergent capsule W1 has a base area (length L × width B) of 2.3 cm × 3.1 cm and a height H of 2.0 cm, measured without the laterally projecting sealed rim. Due to its small width of 3.1 cm and length of 2.3 cm, both its handling is reduced and the risk of ingestion is increased. Another prior art detergent capsule W2 solves this problem by increasing its length and width. However, this requires significantly more detergent or air to be filled, which disadvantageously increases manufacturing costs and storage volume. The prior art detergent capsule W3 also has an increased length and width, but also a small internal volume, thus avoiding all the aforementioned disadvantages. W1 (SdT) W2 (SdT) W3 (according to the invention) Internal dimensions L x W x H 2.3 cm x 3.1 cm x 2.0 cm 2.8 cm x 3.7 cm x 2.0 cm 2.8 cm x 3.7 cm x 1.3 cm Fillable volume 6,5 ml 10 ml 6,5 ml

[0029] A method for manufacturing a detergent capsule according to the invention involves, in a first step, placing a layer of plastic film onto a cavity that has a rim and an internal protrusion for forming the seal. In a further step, the plastic film is deep-drawn or vacuum-formed into the at least one cavity—preferably with heating and optionally assisted by compressed air—so that the film has an internal protrusion. The protrusion preferably has the same height as the rim, measured from the bottom of the cavity. Subsequently, detergent or detergent components are filled into the cavity lined with the plastic film up to a maximum height of the protrusion, so that the top of the protrusion, which is preferably flat, is free of detergent or detergent components.The cavity is then sealed by placing another sheet of film on top, and this additional film is welded to the plastic film along its edges and on the raised section. The sealing seam is formed by welding the plastic film and the additional film on the raised section together.

[0030] Another method for manufacturing the detergent capsule according to the invention, for ease of implementation on existing equipment, involves, in a first step, placing a layer of plastic film into at least one cavity, which has no internal protrusion for forming the sealing seam. In a further step, the plastic film is deep-drawn or vacuum-formed into the at least one cavity – preferably with heating and optionally assisted by compressed air – so that the film assumes the contour of the cavity. Subsequently, detergent or detergent components are filled into the cavity lined with the plastic film. The cavity is then closed by placing another film on top, and the edge of this additional film is welded to the plastic film.Before or after this welding process, the detergent or detergent components are displaced between the two films by pressing them together, and the seal is formed in this area by welding. Particularly when the displacement of the detergent or detergent component in the receiving space during the creation of the seal displaces air volumes, it is advantageous to perform the pressing to form the seal before welding the edge, so that the displaced air can escape through the still unsealed edge areas.

[0031] The bonding of the layers of the plastic film to form the edge areas and / or the sealing seam of the detergent capsule according to the invention can be achieved, for example, by the action of water and pressure, or by the action of water, pressure and heating below a temperature of approximately 95 °C, or by the exclusive action of temperatures above 90 °C. The resulting flange-like edge areas can be removed, for example, by subsequent laser cutting, die-cutting, or slicing.

[0032] Further embodiments and details of the invention are explained below with reference to the drawing illustrating an exemplary embodiment. The drawing shows: Figure 1 a view of a detergent capsule according to the invention; Figure 2 the detergent capsule according to Figure 1 in perspective.

[0033] The figures show a globally designated detergent capsule with reference symbol 1, which has an outer shell 10 based on a water-soluble plastic film, for example made of polyvinyl alcohol.

[0034] The outer shell 10 encloses an inner receiving space 11, which is closed on all sides and in which a liquid or gel-like detergent is contained in a dosage sufficient for a single washing process, for example 20 g.

[0035] When such a detergent capsule 1 is placed in a washing machine together with the laundry to be washed, the outer shell 10 made of water-soluble plastic film dissolves upon contact with the wash water and releases the detergent held in the receiving chamber 11 in the desired dosage.

[0036] To give the detergent capsule 1 a size suitable for easy handling and good consumer acceptance, while simultaneously counteracting the risk of unintentional oral ingestion or even swallowing, the dimensions of the detergent capsule 1 are initially chosen to be too large in relation to the dosage of detergent filled into the receiving chamber 11. However, the volume of the inner receiving chamber 11 is reduced by a sealing seam 12, which is partially incorporated into the receiving chamber 11 and completely surrounded by the receiving chamber 11 and the detergent contained therein, to such an extent that no air bubble is present in the receiving chamber 11 besides the detergent.

[0037] The outer shell 10 is formed by joining a lower and an upper layer of the plastic film together at their edges, enclosing the metered detergent, for example by thermal welding at temperatures above 95 °C. This creates a flange-like circumferential edge area 100, which can optionally be removed by punching or laser cutting.

[0038] Similarly, the two layers of the plastic film in the area of ​​the inserted sealing seam 12 are brought directly onto the system and connected to each other, for example thermally welded, so that the detergent filled in the receiving chamber 11 is displaced in the area of ​​the sealing seam 12.

[0039] Instead of purely thermal welding, the two layers of the plastic film can also be joined together by the action of water, pressure and temperatures below 95 °C or by the action of water and pressure.

[0040] It is understood that the size, dimensions, and design of the sealing seam 12 can be freely chosen by a person skilled in the art based on the circumstances, provided that the inclusion of the sealing seam 12 does not divide the receiving space 11 into two completely separate compartments. For this to be the case, at least one free end of the sealing seam 12 must be partially surrounded by the receiving space 11 or, as in the illustrated embodiment, completely surrounded by the receiving space 11.

[0041] Depending on the manufacturing process, the conversion of existing plants for the production of detergent capsules may only require the installation of at least one raised section in the mold cavities to form the sealing seam 12.

[0042] The detergent capsule 1 described above can therefore, for example, hold a dosage of 20 g of detergent in the receiving chamber 11, but in terms of external dimensions correspond to a detergent capsule 1 for holding 24 g of detergent, whereby the introduction of the sealing seam 12 largely avoids an otherwise unavoidable air bubble in the receiving chamber 11. Reference symbol list:

[0043] 1 Detergent capsule 10 Outer shell 11 Receptacle 12 Seal seam 100 Flange-like edge area

Claims

1. Detergent capsule (1) comprising an outer casing (10) based on a water-soluble plastics film, which encloses at least one inner receiving space (11) in which detergent or detergent components are received, characterized in that at least one receiving space (11) comprises at least one sealing seam (12) formed in regions, which partially but not completely divides the receiving space (11), the sealing seam (12) projecting into the receiving space (11) starting from the periphery of the outer casing (10) and being partially surrounded by the receiving space (11).

2. Detergent capsule (1) according to claim 1, characterized in that the outer casing (10) is formed by two film layers which are connected to one another at the edges and in the region of the at least one sealing seam (12).

3. Detergent capsule (1) according to one of claims 1 to 2, characterized in that the plastics film is based on polyvinyl alcohol or polyvinyl alcohol copolymers.

4. Detergent capsule (1) according to one of claims 1 to 3, characterized in that the plastics film is single-layered or multi-layered.

5. Detergent capsule (1) according to one of claims 1 to 4, characterized in that it comprises one to four discrete receiving spaces.

6. Detergent capsule (1) according to one of claims 1 to 5, characterized in that the sealing seam (12) has a width of 0.5 to 5 mm.

7. Method for producing a detergent capsule (1) according to one of claims 1 to 6, comprising the steps whereby i. a layer of a water-soluble plastics film is guided onto a cavity which comprises an edge and an inner elevation to form the sealing seam, ii. the plastics film is deep-drawn into the at least one cavity, iii. detergent or detergent components are filled into the cavity lined with the plastics film, up to the maximum height of the elevation iv. the cavity is closed by applying another film, v. the further film is fused to the plastics film at the edges and on the elevation.

8. Method for producing a detergent capsule (1) according to one of claims 1 to 6, comprising the steps whereby i. a layer of a water-soluble plastics film is guided onto a cavity which comprises an edge ii. the plastics film is deep-drawn into the at least one cavity, iii. detergent or detergent components are filled into the cavity lined with the plastics film iv. the cavity is closed by applying another film, v. the further film is fused to the plastics film at the edges, vi. before or after fusing the further film to the plastics film, the sealing seam is formed and fused by displacing detergent.

9. Method according to claim 7 or claim 8, characterized in that the plastics film and the further film are fused together under the influence of water and pressure or under the influence of water, pressure and heating below 95 °C or under the influence of temperatures above 95 °C.