WO2020193624A1

WO2020193624A1 - Barrier cartridge having a piston

Info

Publication number: WO2020193624A1
Application number: PCT/EP2020/058349
Authority: WO
Inventors: Johannes VON STAUFFENBERG
Original assignee: Ritter Gmbh
Priority date: 2019-03-27
Filing date: 2020-03-25
Publication date: 2020-10-01

Abstract

The head side of a cartridge has a side wall (12) and an end wall (13). The walls (12, 13) are provided with a first barrier layer (3) or a second barrier layer (4). The second barrier layer (4) is arranged on the inner side of the end wall (13), not on the inner side of the side wall (12). For this purpose, the side wall (12) with the first barrier layer (3) can extend beyond the top side of the end wall (13). Thereby, an additional protection against diffusion from the side of the side wall (12) in the transition area between side wall (12) and end wall (13).

Description

TITLE

Barrier cartridge having a piston

TECHNICAL FIELD

The present application concerns a cartridge having barrier function, comprising a base body with a side wall and an upper end wall, wherein the base body is manufactured as a single piece injection-moulded part, and wherein, a first barrier layer is arranged on the outer side of the side wall and a second barrier layer is arranged on the inner side of the upper end wall. In addition, the application relates to a piston having barrier function, and a system comprising a cartridge with a side wall and a piston inserted into the cartridge.

PRIOR ART

Containers, such as cartridges, are generally made of plastic or aluminium. A piston is inserted into the cartridge after filling the cartridge with filling material. By pushing the piston forwards, the material is dispensed from the inner space of the cartridge via an opening facing away from the piston.

There is a plurality of filling materials that are sensitive to their ambient atmosphere, in particular, to moisture, hydrogen and/or oxygen. This means that plastic cartridges and plastic pistons, since they are not impermeable, are principally unsuitable for storing these materials. Aluminium cartridges, on the other hand, are very material-intensive; the manufacturing process is energy-intensive, therefore being expensive to manufacture overall. In addition, aluminium cartridges are prone to damage, and if dented, the entire cartridge may be unusable. Handling is therefore difficult; the packaging effort is higher. In addition, setting the pistons after the filling process is more expensive than with plastic cartridges, since the setting speed must be higher.

Furthermore, there are cartridges made of a carrier material (plastic, cardboard, etc.) on which an impermeable barrier layer is applied and deposited, respectively. The barrier layer can be applied as a coating in different methods, such as CVD/PVD, as glued foil, as lamination, etc. The problem, however, is that, in transition areas, and at edges of the cartridge and/or in the transition area between piston and cartridge, non-sealed areas can be present through which gas, such as water vapour, can diffuse. A gap can also arise between piston and cartridge, particularly due to thermal expansion effects.

OBJECT OF THE INVENTION

The object of the invention is to provide a cartridge, a piston or a cartridge-piston system, which ensure an improved sealing of the interior space of the cartridge against the diffusion of gases, in particular, of water vapour.

TECHNICAL SOLUTION

The object is achieved by providing a cartridge, a piston and a cartridge-piston system according to claims 1, 9, 15, 18, 22 and 23 respectively. Preferred embodiments and features are described in the dependent claims.

According to the invention, a cartridge having barrier function is provided, comprising a base body with a side wall and an upper end wall, wherein the base body is manufactured as a single-piece injection-moulded part, and wherein a first barrier layer is arranged on the outer side and/or on the inner side of the side wall, a second barrier layer is arranged on the inner side of the upper end wall, characterized in that in the transition area between the barrier layers between the end wall and the side wall a passage area having a first width is arranged in the base body between the barrier layers, the end wall has at least a greater thickness in the transition area adjacent the side wall in such a way that a diffusion path is arranged between the outer side of the end wall and the interior space of the cartridge for fluid diffusing through the passage area, which corresponds to at least a minimum diffusion path. The area of the side wall with greater thickness is arranged in particular so that the minimum diffusion path between the outer side of the end wall and the passage area is exceeded.

The provision of the base body as a single-piece injection-moulded part brings advantages in terms of stability, reduces the assembly effort, allows for an optimization of wall thicknesses, thereby reducing the total weight of the cartridge. Due to the stability (there are no breaking points at connecting lines), higher filling pressures and higher discharge pressures can be applied. In particular, the cartridge has an opening formed in the end wall for discharging filling material. In the area of this opening, the wall thickness of the end wall is preferably reduced again. This allows the plastic material from which the cartridge is preferably made to be used as sparingly as possible. In particular, the cartridge is manufactured as a single part/single piece by an injection-moulding method.

The area of greater thickness in the end wall is referred to in the following as a thickening.

The thickening (viewed from the outer side to inward in a longitudinal sectional view of the cartridge) has an extension of the side wall extending beyond the end wall, as well as a transition area and an end wall area that has smaller wall thickness than the thickening has. At the boundary between the transition area and the extension of the side wall, the transition area is just as thick as the extension of the side wall. Inwardly (towards the dispensing opening), the wall thickness in the transition area may be reduced, however, depending on the distance from the side wall, it is reduced only to the extent that at each point the minimal diffusion path between the outer side of the end wall and the passage area or the inner side of the cartridge is still exceeded. The minimum diffusion path can essentially correspond to the wall thickness of the extension of the side wall.

Preferably, the diffusion path is arranged between the outer side of the end wall and the passage area. The passage area ends in the interior space of the cartridge.

The thickness in the area of thickening, for example, can be more than 2 mm, in particular 3-5 mm, and extend from the edge of the shoulder of the cartridge radially 3-4 mm inwards towards the dispensing opening. For example, the thickness in the area near the dispensing opening can be half the thickness of the thickening near the edge of the shoulder.

In particular, the ratio of the wall thickness in the area of thickening (near the edge) to the wall thickness in the radially inside area of the end wall may be 1.1 - 3, in particular 1.5 - 2.5, more preferably 1.8 - 2.2.

Between the thickening and the radially inside area, a step lying on the outer side of the end wall can be provided, however, the transition can also be continuous, i.e. continuously (e.g. at an angle opposite the horizontal of 10°-45°) and/or flatten steadily and/or in smaller steps, e.g. over a range of 1-2 mm.

The area of the end wall is s x R² in total, wherein R is the (averaged) radius of the end face, including the surface of the opening of the cartridge in the end wall or the area taken by the application nozzle. If the thickening has a radial extension of V and runs around the circumference of the end face, the ratio of the complete area and the area of the thickening is p x R² / (p x R² - p x (R-V)²). In preferred embodiments, the ratio of the surfaces is 1-4, in particular 1.5-3.5, more preferably 2-3. A transition area between the thickening and flattened wall thickness near the centre of the end wall is defined to be part of the flattened part of the end face.

The passage area of the width b has, in particular, a circular or annular, elliptical, rectangular or square cross-section. If this patent application refers to radii, an average radius is meant, provided that the shape of the end wall differs from a circle. The width b may correspond to the thickness of the side wall. The side wall may have a thickness of 0.5-3 mm, in particular of 1-2 mm, more preferably 1.25-1.75 mm. The ratio between the thicknesses of the side wall and the extension (width V) of the thickening can be between 0.1 and 1, in particular between 0.2 and 0.6, more preferably, between 0.3 and 0.5. The ratio between the wall thickness of the side wall and the wall thickness in the area of the thickening may be, in particular, 0.1-0.6, more preferably 0.2-0.5, more preferably 0.25-0.45. The wall thickness of the end wall in the area of thickening may be, for example, 1-10 mm, preferably 1.5-6 mm, in particular 2-5.5 mm, more preferably 3-5 mm.

The ratios and size specifications referred to in this application shall be claimed in all conceivable combinations.

The second barrier layer can be formed as an inlay attached to the inner side of the end wall. The inlay can be or comprise an aluminium foil. It may e.g. be a foil having an aluminium coating.

The second barrier layer may be attached to the inner side of the end wall via at least two attachment seams/seals.

The first attachment seam can extend essentially around the circumferential area of the second barrier layer. This attachment seam can be, for example, 2-5 mm wide. The thickening, which is arranged adjacent to the attachment seam, has a radial extension towards the inside, which is at least as wide as the attachment seam.

In particular, the cartridge may have an outflow channel for discharging filling material. The outflow channel is connected with the interior space of the cartridge through an opening. The second attachment seam can essentially extend at the inner side of the end wall around the edge of the opening. This attachment seam can have a width of approx. 1-2 mm.

The second barrier layer may be formed as an aluminium foil laminated with a weldable layer.

The passage area can be a gap between the first barrier layer and the second barrier layer. The gap can extend within the side wall.

According to the invention, a cartridge with a barrier function is provided, comprising a base body (which consists, for example, of a thermoplastic material) having a side wall and an (upper) end wall, wherein a first barrier layer is arranged on the outer side and/or on the inner side of the side wall and a second barrier layer is arranged on the inner side of the upper end wall, and the first barrier layer and the second barrier layer are arranged in the transition area between the side wall and the end wall in such a way that a width of a gap between the first barrier layer and the second barrier layer is reduced, and/or a gap is formed which forms a diffusion path between the first barrier layer and the second barrier layer.

In particular, the first barrier layer and the second barrier layer overlap in the transition area between the side wall and the end wall at least partially and the gap lies in the overlap area between the barrier layers. The overlap refers to a projection of the second barrier layer on the first barrier layer. The barrier layers overlap without coming into contact with each other. The diffusion path extends between the overlapping sections of the two barrier layers.

In the transition area between the side wall and the upper end wall, an angle filled with wall material can be formed, the inner side of which is at least partially covered with the second barrier layer.

The first barrier layer or coating can be provided as a label that is applied at least in sections to the outer side and/or the inner side of the base body (in particular, being glued). The barrier layer or coating may be glued on or thermoplastically applied, e.g. by means of an in-mould labelling method (IML), to the outer side and/or the inner side of the base body.

The first barrier layer and the second barrier layer can be arranged on the base body of the cartridge, forming an overlapping area. In particular, an overlapping arrangement of the barrier layers can be carried out when using an in-mould method for applying at least one of the barrier layers. Preferably, the cartridge may be usable for predetermined temperature profiles, for example, from -25°C to +100°C.

When fixing the label to the wall of the cartridge, two ends of the label overlap. To this end, the following methods have proved suitable for the variant of affixing a label:

- The label is coated with a varnish instead of a laminate.

- The paint/printing is omitted from the overlap of the label to ensure optimum adhesion.

- The adhesive label can be enlarged to the extent that the overlap is greater and there is no diffusion at the adhesive site.

- In the overlapping area, the label is not printed or coated.

- The overlap area of the label should be greater than 5 mm in order to delay the diffusion of humidity.

- The piston is sealed in the cartridge using wax, in addition to the mechanical sealing on the cartridge inner wall by means of a sealing lip.

- The coefficient of thermal expansion of plastic is taken into account in the design of the barrier function.

The second coating can preferably be formed as an inlay, which is connected in particular by means of heat sealing or bonding or by an in-mould labelling method (IML) to the wall of the base body.

On its end face, the cartridge can have, depending on the application, an outlet nozzle (with or without thread) or a moulded nozzle.

In another embodiment of the invention the first and/or second barrier layer can be attached to the base body, for example, by flanging, e.g. outer side or inside at the outlet. The first and/or second barrier layer can be laminated with a weldable layer.

A piston according to the invention having barrier function, in particular, for use in a cartridge as described above, is provided, wherein the barrier function is implemented by means of a barrier layer arranged on the top side and at least over an area of the side wall of the piston. Thereby, the barrier layer is arranged on the outer side of the piston and/or at its front. The piston can, for example, be provided with a barrier foil, which is attached to the piston, for example, by gluing, welding, sealing, by coating or as an inlay.

The barrier layer of the piston can be arranged on a hood or formed as a hood, which is arranged on the top side and at least on an area of the side wall of the piston.

The barrier layer can be clipped onto the piston or overlaid over the piston. In between, for example, oil can be introduced to improve adhesion.

The piston has a sealing lip aligned with the interior space of the cartridge. The sealing lip extends diagonally forwards in the insertion direction of the piston. The barrier layer is imposed on the piston and/or the sealing lip or covers it.

A system according to the invention comprises a cartridge, in particular, as described above, having at least a side wall and a piston inserted in the cartridge, in particular, as described above, wherein a third barrier layer, in particular a wax layer, is arranged in the interior space of the cartridge in the area of the contact surface between the inner side of the side wall and the outer side of the piston.

With the help of the invention, the permeation and diffusion of gases and vapours is to be reduced to an acceptable level. The level depends on the sensitivity of the filling materials for permeated gases and on the specified minimum shelf-life. The permeation/ diffusion depends essentially on the gas, its pressure or density, the cartridge material and the wall thickness of the cartridge. In order to reduce permeation and diffusion, the selected cartridge material should have as low a free volume as possible (free space between the molecular chains). For example, it is less the higher the crystallinity of a thermoplastic is, and it is less the higher the degree of crosslinking of a thermoset or elastomer is.

The barrier layer can be a layer or layer structure comprising a metal, in particular aluminium, and or glass.

Another system of the invention comprises a cartridge as described above, and a piston as described above.

The impermeable layer of the first and/or the second barrier layer has a thickness of at least 5 pm, and less than or equal to 70 pm, in particular less than or equal to 35 pm, more preferably less than or equal to 15 pm, in particular less than or equal to 9 pm, and can be, in particular, a non-adhesive aluminium layer and/or a glass layer. If the impermeable layer may be provided in the form of a label, the impermeable layer can be embedded in a layer system as follows:

1. As a carrier: Siliconized carrier paper, e.g. between 2 to 10 pm/m² of silicone, in particular 7 pm/m² of silicone, glazed paper. An adhesive layer is attached to the carrier paper. The carrier paper is removed before sticking the barrier layer onto the cartridge. The support layer is not part of the barrier layer.

2. Glue, e.g. acrylic-dispersion glue.

3. The mentioned impermeable layer.

4. Optionally, a surface printed in white.

5. Optional flexographic printing.

6. Preferably, a layer of adhesive varnish (bonding composite with laminate).

7. Preferably, a transparent laminate layer of a thickness between 5 pm and 25 pm, in particular, 12 pm; or varnish.

A method for manufacturing a cartridge according to the invention as described above includes the following steps:

(a) manufacturing the base body in an injection-moulding method as a single-piece component. b) Attach a coating to the outer side of the side wall, for example by sticking a label with a barrier layer. c) attaching an inner barrier layer, for example, an inlay on the end wall, particularly on the inside of the end wall.

Step c) can be done, for example, by sealing along one or a plurality of attachment seams. The sealing seam can be arranged on the inner side of the side wall and/or on the end wall. It can be arranged as described above on the end wall along a circumference of the face wall-side barrier layer. A second attachment seam can be formed around the dispensing opening. In this type of fastening, a simple aluminium foil can be used as an inlay, which is fixed on an ideal flat and smooth fastening surface. The two sealing seams do not result in a dead volume. The formation of cavities between the second barrier layer and the end wall, in which water or oxygen can accumulate, is prevented.

The second barrier layer can be arranged in a further embodiment on the outer side of the end wall.

By manufacturing the base body in an injection-moulding method, the cartridge is straighter, or the surfaces are smoother than, for example, in an extrusion method. This fact supports the application of the barrier layers. The base body consists of a suitable plastic with a density between 0.9 and 2.0 g cm^-3, in particular between 1.1 and 1.8 g cm^-3.

In an alternative embodiment the second barrier layer can be arranged or attached to the cartridge by over-moulding the second barrier layer with the cartridge body (in-moulding method). The first and/or the second barrier layer can be, for example, impermeable foils that are over-moulded with plastic from the outer side or from the inside.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features and advantages of the invention result from the following description of preferred exemplary embodiments based on the figures. The figures show:

Figure 1 is a sectional representation of a first embodiment of the cartridge according to the invention;

Figure 2 a detail from Figure 1 :

Figure 3 a detail of an alternative second embodiment of the invention.

Figure 4 is a detail of a third embodiment of the invention;

Figure 5 is a detail of a fourth embodiment of the invention;

Figure 6 a sectional representation of a fifth embodiment of the cartridge according to the invention;

Figure 7 an embodiment of a label for a cartridge according to the invention, and Figure 8a, 8b further embodiments of a label for a cartridge according to the invention. DESCRIPTION OF PREFERRED EXEMPLARY EMBODIMENTS OF THE INVENTION

Figure 1 shows a first embodiment of a cartridge 1 according to the invention with a piston 2 according to the invention, which is inserted into the cartridge. The cartridge consists of a base body 10 made of plastic, e.g. polyamide, polyethylene or polypropylene, PET, with an interior space 11.

A first (impermeable) barrier layer 3 is arranged on the outer side of the base body 10. The first barrier layer 3 may include, for example, a barrier lacquer and/or a glass layer (SiO_x). In particular, the barrier layer 3 can be impermeable to water vapour, oxygen and/or hydrogen. Preferably, the barrier layer 3 comprises a layer of aluminium and/or a glass layer (SiO_x). The aluminium layer/glass layer can be laminated or applied by CVD/PVD or other suitable coating methods. Alternatively, the layer can be attached as a foil to the base body 10. In particular, the layer 3 can be provided as a label, which is glued, for example, over the outer side 120 of the side wall 12 of the base body 10. In another particular embodiment, the barrier layer 3 can be glued on or thermoplastically applied, e.g. by an in-mould labelling (IML) method.

The base body 10 is manufactured in one piece in an injection-moulding method. It has a nozzle 7 with muzzle 70 and an opening 700, via which the interior space 11 of the cartridge is connected to the muzzle 70.

The base body 10 also has a rear opening 71, over which the cartridge is filled and into which a piston 2 is then inserted.

In order to protect the top side of the cartridge 1 from the permeation/ infusion of gases, a second (impermeable) barrier layer 4 can be arranged on the inner side of the upper wall 13. This can be arbitrarily formed in principle, for example, as explained above. In particular, the barrier layer 4 can be formed as a foil or inlay, which is attached to the inner side 130 of the upper wall 13, in particular, by heat sealing.

A connecting line between the second barrier layer and the inner side of the wall of the base body can be arranged on one or a plurality of the following sections of the wall: (i) on the outer perimeter of the inner side of the end wall. This type of fastening is also possible when there is an outwardly curved end wall. The barrier layer (e.g. aluminium foil) lies flat within the connecting line or connecting seam (ii) Like (i), however, the barrier layer extends over a section of the side wall and is connected to it. (iii) Attachment around the circumference of the opening 700, e.g. in combination with (i) or (ii). This solution avoids the presence of a dead volume or cavity between the end wall 13 and the barrier layer 4. In particular, a good connection is possible if the inner side of the end wall is flat.

According to the invention, the first barrier layer 3 and the second barrier layer 4 are arranged in such a way that a gap S (see Figures 2, 3) which is located between the layers is reduced or minimized. In particular, the gap width is reduced or the diffusion path in the plastic filling the gap S is extended. The barrier layers 3 and 4 are therefore arranged so that they overlap in the area of the gap S or at least projections of the barrier layers on the side wall overlap.

In Figures 2 and 3, two exemplary embodiments for possible arrangements of barrier layers 3 and 4 in the transition area between side wall 12 and upper wall 13 are shown.

In the case of Figure 2, the second barrier layer 4 is arranged so that it covers not only the inner side 130 of the upper wall, but also a section 1210 of the inner side 121 of the side wall 12. A length L of the gap S between the first barrier layer 3 and the second barrier layer 4 is formed by the overlap or enlarged (in relation to an arrangement of the barrier layers 3 and 4 without an overlap). This significantly extends the permeation/ diffusion path for gases through the slit S so that a penetration of gases into the interior space 11 is significantly reduced.

In the case of Figure 3, the second barrier layer 4 is arranged in such a way that it also covers a section 1220 of an angle 122 provided besides the inner side 130 of the upper wall, which angle 122 is arranged as material filling between the upper wall 13 and the side wall 12. The width of the gap S is thus reduced from a first value B to a second value b.

Figure 4 shows another exemplary embodiment. Here the second barrier layer was dispensed with. Instead, a greater permeation/ diffusion path L is provided by an enlarged wall thickness D of the end wall 13. The diffusion path L corresponds to the wall thickness D. The wall thickness d of the side surface 12, on the other hand, unchangedly remains smaller, and the outer wall supports the first barrier layer 3. The wall thickness D of the end wall 13 is dimensioned in such a way that the probability of diffusion of gases into the interior space of the cartridge via the end wall 13 is sufficiently low.

Figure 5 shows another exemplary embodiment. This largely corresponds to the exemplary embodiment of Figure 2. However, the second barrier layer 4 is arranged only on the inner side of the end wall 13, not on the inner side of the side wall 12. In order to prevent diffusion, the side wall 12 with the first barrier layer 3 can extend beyond the top side of the end wall 13. Thereby, additional protection is provided against diffusion from the outer side of the side wall 12 in the transition area between side wall 12 and end wall 13.

The latter embodiment, however, can also be implemented without protruding the side wall 12 with the first barrier layer 3 over the top side of the end wall 13.

A further embodiment of the invention is shown in Figure 6. The same components are marked with the same reference numbers and letters as in the previous description.

Unlike in Figure 5, the end wall 13 or the transition between the side wall 12 and the end wall 13 has a thickening, which has a maximum value D in the longitudinal direction (i.e. in the direction of the side wall). The thickening is dimensioned in such a way and extends at least as far inwards towards the central longitudinal axis of the cartridge in such a way that, between the passage S of the width b and the outer side of the end wall or thickening, a minimum diffusion path L is continuously remained or exceeded. Towards the centre of the end wall, the thickening is reduced or is no longer present in the interior area of the end wall. This reduces material consumption for manufacturing the cartridge, while at the same time not exceeding a maximum value for permeation by gases.

The protruding edge at the outer circumference of the end face 13 can have any geometry that ensures a minimum diffusion path L, while the regular wall thickness of the side and the end wall fall below this diffusion path, but are protected by barrier layers 3, 4 from the passage of gases and vapours.

The second barrier layer 4 can be connected via two sealing seams U1 and U2 to the inner side of the end wall 13. Its outer seam U1 extends along the outer circumference of the second barrier layer 4 (e.g. an aluminium foil). The inner seam U2 extends around the opening 700 of the muzzle 70. The barrier layer 4 can either span the opening 700 or the opening 700 can be accessible by a corresponding opening in the barrier layer 4 from the inside.

If in a particular embodiment the barrier layer 4 extends over the opening 700, the barrier layer 4 can be opened by actuating a closure or by mounting of an additional component such as a mixer nozzle on the nozzle 7.

The top side 20 and an area of the side walls 21 of the piston 2 is covered by a hood 5 with a barrier layer, e.g. an aluminium layer. The hood 5 is put over the piston 2. Since the hood allows a certain level of movement play, the seal in the gap G between the cartridge inner wall and the outer side of the piston 21 can be improved. In particular, technically high- quality pistons, e.g. with an external elastic sealing lip, can be used. The sealing lip follows the cartridge inner wall during heat elongation of the cartridge 1, and the hood follows the elastic sealing lip, which improves contact with the cartridge inner wall. The barrier layer 5 can be clipped on the piston 2. As an additional seal for sealing the gap G, a layer arranged in this area 6 of material with high thermal expansion can be used, e.g. wax.

In an embodiment of the invention, the first barrier layer 3 can be formed as a label and/or be attached to the side wall 12 of the single-piece cartridge body of the cartridge by in-mould labelling (IML). Figure 7 shows a label 3 that can be used for this purpose. In an IML method, for example, a printed aluminium foil is inserted into the mould, then the cartridge 1 is injection-moulded as a single piece. The barrier layer adheres to the cartridge body by means of the injection process.

The label 3 can be provided as a layer system with at least one layer with barrier properties (e.g. metal layer such as aluminium), but also with other layers without barrier properties, e.g. PE, PP and/or adhesive layers. A preferred structure of the label 3 is a layer with a barrier function, which is provided on both sides with a plastic layer.

If one or a plurality of punches or breakthroughs are formed into the lower foil of the label in the overlap area of the ends of the label, the plastic penetrates into these punches and breakthroughs, respectively, and thus (directly) connects to the outer foil section. This improves the permeation density/ diffusion density of the overlap area.

In-mould labelling is particularly advantageous for the application of the external label 3, since production steps of the usual labelling (e.g. by gluing) can be economized. The label 3 is already applied during the injection-moulding method at the same time the cartridge is manufactured. In addition, the formation of wrinkles and blisters is reduced.

However, when using IML method, precautions must be made that the barrier layer 3 fully covers the side wall 12. For this purpose, either the label 3 can be arranged on impact (i.e. the two ends face-to-face) on the side wall 12. However, very high requirements for the accuracy of the arrangement must be met in order to prevent permeation and diffusion due to an uncovered gap. Another option is to later cover the gap with a barrier layer strip, e.g. by glueing. Alternatively, the label 3 attached to the side wall 12 has an overlap area 30 (cf. Fig. 7 with overlap areas 30 above and below), in which each end section 30 (top section) of the one end arranged above the end section 30 (bottom section) of the other end is respectively arranged. Reference number 300 designates the recess/punching in an end area 30 (bottom section). In the area 301, which is superposed with area 300 when the label is attached to the wall of the cartridge, the label 3 directly adheres to the cartridge.

It can be problematic that the label 3, which, for example comprises a PP (PE) layer above an aluminium barrier layer and above another PP (PE) layer, does not adhere sufficiently well in the overlap area 30 without additional measures. This is because the barrier layer transports too much heat to the outer side of the tool so that a melting temperature sufficient for an IML method is not reached. In addition, the cartridge 1 shrinks more than the barrier layer 3 (or the layer having barrier function) after being manufactured so that wrinkles and areas of insufficient adhesion form in the overlap area.

This is solved by implementing at least one of the following measures in the overlap area in at least one of the end sections of the label:

1. A material recess e.g. in the form of a punching 300 in the overlap area 30 can be formed, see Fig. 8a.

2. A plurality of openings 300 can be formed along the overlap area 30 in the form of a plurality of incisions 300 or cuts, for example, in the shape of lines or crosses arranged next to one another along the length of the overlap area (not shown) or other geometrical shapes, such as one or more wave-like cuts extending along the overlap area (not shown). These incisions can be manufactured in the label 3 before the in mould process as cuts, crevices, breakthroughs, punctures, holes, punches, etc., see Fig. 8b.

The shape of the cuts or recesses can be arbitrary, for example, in the form of side-by-side holes, crosses, incisions transverse to the length of the overlap area, punctures, etc. The means must be suitable for serving the purpose of compensating for different heat dissipation or different shrinkage behaviour of the barrier layer 3 or the layer with a barrier function within the barrier layer 3, respectively. Another potential geometry for incisions would be a wave like material recess that extends along the edge or along the overlap area of the label. It would also be conceivable to subsequently applying glueing or welding the overlap area 30 of a label 3 which had been attached to a cartridge by IML method. It could, e.g. be used heat sealing, ultrasound sealing, etc.

The overlap area 30 in the IML method can in particular have a width of at least 0.5 mm, in particular of at least 1 mm.

Alternatively, the barrier layer can be provided in the form of a label which, after

manufacturing the cartridge using the injection-moulding method, is glued onto the cartridge. In this case, the provision of an overlapping area is unproblematic. The formation of wrinkles in the label due to the shrinking behaviour of the cartridge body does not occur when the label is applied after the cartridge has cooled down.

The label may have a layer of adhesive on the underside, a printed aluminium layer on top, and a foil above it. An overlap area may still be required due to the barrier properties of the label. In addition, it could be useful to machine the label in the overlap area, e.g. by locally removing one of the layers so that the end part (overlapping end) of the label is glued directly to the aluminium layer of the other end of the label (other overlapping end) in the overlap area. If the bottom foil is provided with a recess, the upper foil sticks directly on the aluminium layer, thereby reducing diffusion.

REFERENCE LIST

1 cartridge

10 base body

11 interior space

12 side wall

120 outer side of the side wall

121 inner side the side wall 1210 section of the inner side

122 angle

1220 section of the angle

13 upper (end) wall

130 inner side of the upper wall

2 piston

20 top side

21 side wall

3 first barrier layer

30 overlap region

300 recess

301 area of adhesion

4 Second barrier layer

5 hood with a barrier layer

6 Wax layer

7 Nozzle

70 Opening channel

700 upper opening

71 lower opening

Claims

1. A cartridge (1) having barrier function, comprising a base body (10) with a side wall

(12) and an upper end wall (13), wherein the base bpasody (10) is manufactured as a single-piece injection-moulded part, and wherein a first barrier layer (3) is arranged on the outer side (120) and/ or on the inner side of the side wall (12), and a second barrier layer (4) is arranged on the inner side (130) of the upper end wall (13), characterized in that,

in the base body (10), between the barrier layers in the transition area between the end wall (13) and the side wall (12), a passage area (S) with a width (b) between the barrier layers (12, 133) is arranged,

wherein the end wall (13) has a greater thickness (D) than the side wall (12) at least in the transition area adjacent the side wall (12) in such a way that, between the outer side of the end wall (13) and the interior space of the cartridge, a diffusion path is arranged for fluids to pass through the passage area (S), the length of which corresponds to at least a predetermined minimum diffusion path length (L).

2. The cartridge (1) having barrier function according to claim 1, wherein the diffusion path is arranged between the outer side of the end wall (13) and the passage area (S).

3. The cartridge (1) having barrier function according to claim 1 or 2, wherein the second barrier layer (4) is formed as an inlay attached to the inner side of the end wall (13).

4 The cartridge (1) having barrier function according to claim 1, wherein the second barrier layer (4) is attached to the inner side of the end wall (13) by at least one attachment seam (Ul), in particular by at least two attachment seams (Ul, U2).

5. The cartridge (1) having barrier function according to claim 4, wherein the first

attachment seam (Ul) essentially extends around the circumferential area of the barrier layer (4).

6. The cartridge (1) having barrier function according to claim 4, wherein the end wall

(13) has an opening (700) connecting the interior space of the cartridge (1) and an outflow channel (70) for dispensing filling material, wherein the second attachment seam (U2) is arranged on the end wall (13) and essentially extends around the edge of the opening (700).

7. The cartridge (1) having barrier function according to claim 1, wherein the second barrier layer (4) is formed as an aluminium foil coated with a weldable layer.

8. The cartridge (1) having barrier function according to claim 1, wherein the passage area (S) is formed as a gap between the first barrier layer (3) and the second barrier layer (4) and extends within the side wall.

9. A cartridge (1) having barrier function, comprising a base body (10) with a side wall (12) and an upper end wall (13), wherein the base body (10) is manufactured as a single-piece injection-moulded part, wherein a first barrier layer (3) is arranged on the outer side (120) or the inner side of the side wall (12), and a second barrier layer (4) is arranged on the inner side (130) of the upper end wall (13), and in the transition area between the side wall (12) and the end wall (13) the first barrier layer (3) and the second barrier layer (4) are arranged in such a way that a width (b) of a gap (S) between the first barrier layer (3) and the second barrier layer (4) is reduced, and/or a gap (S) is formed with a diffusion path of a length (L) between the first barrier layer (3) and the second barrier layer (4).

10. The cartridge (1) having barrier function according to claim 1 or 9, wherein a portion of the first barrier layer (3) and a projection of the second barrier layer (4) at least partially overlap in the transition area between the side wall (12) and the end wall (13), and at least a portion of the gap (S) lies in the overlap area (1210) between the barrier layers (3, 4).

11. The cartridge (1) having barrier function according to claim 1 or 9, wherein in the

transition area between the side wall (12) and the upper end wall (13) an angle filled with wall material (122) is formed, the inner side (1220) of the angle being at least partially provided with the second barrier layer (4).

12. The cartridge (1) having barrier function according to claim 1 or 9, wherein the first barrier layer (3) is provided as a label and attached (in particular glued ) to the outer side and/or the inner side of the base body (10), and/or the first layer (3) is provided by sticking an impermeable layer or an impermeable layer structure on at least a wall of the cartridge (1), and/or the first barrier layer (3) is provided by applying an impermeable coating to at least a wall of the cartridge (1), all by means of a thermoplastic method, in particular, by means of an in-mould labelling (IML) method.

13. The cartridge (1) having barrier function according to claim 1 or 9, wherein the second barrier layer (4) is formed as an inlay, which is, in particular, connected to the wall of the base body (10) by means of a heat sealing or gluing or a thermoplastic method, in particular, by means of an in-mould labelling method (IML).

14. The cartridge (1) having barrier function according to claims 1 or 9, wherein the first barrier layer (3) is arranged in an overlapping manner on the base body (10) of the cartridge (1).

15. A cartridge (1) having barrier function, comprising a base body (10) with a side wall (12) and an upper end wall (13), wherein the base body (10) is manufactured as a single-piece injection-moulded part, and wherein a first barrier layer (3) is arranged on the outer side (120) or on the inner side of the side wall (12) and a second barrier layer (4) is arranged on the inner side (130) of the upper end wall (13), characterized in that

at least the first barrier layer (3) is formed as a label, which is arranged on the side wall (12) by means of an in-mould labelling (IML) method, wherein the label (3) comprises a layer system with at least one layer having barrier function.

16. The cartridge having barrier function according to claim 15, wherein the label (3) arranged on the base body (12) has an overlap area (30) in which one end section of the label (3) overlaps with the other end section of the label, wherein the label in at least one of the end sections has means to compensate for a different coefficient of thermal expansion between the base body (12) and the layer having barrier function.

17. The cartridge having barrier function according to claim 16, wherein the means for compensating for a different thermal expansion coefficient between the base body (12) and the layer having barrier function comprises at least one of a punching (300) and indents and cuts and openings formed in the barrier layer (3).

18. A piston (2) having barrier function, in particular for use in a cartridge according to one of the preceding claims 1, 9 or 15, wherein the barrier function is fulfilled by means of a barrier layer (5) arranged on the top side (20) and at least across an area of the side wall (21) of the piston (2).

19. The piston (2) according to claim 18, wherein the barrier layer (5) is arranged on a hood, which is arranged on the top side (20) and at least on an area of the side wall (21) of the piston (2).

20. The piston (2) according to claim 18, wherein the barrier layer (5) is clipped to the piston (2) or overlaid over the piston (2).

21. The piston (2) according to claim 18, wherein the piston has a sealing lip diagonally aligned towards the interior space of the cartridge.

22. A system comprising a cartridge (1), in particular according to one of claims 1, 9 or 15, comprising a side wall (12) and a piston (2) inserted in the cartridge (1), in particular a piston according to claim 18, wherein a seal (6), in particular a wax layer, is arranged in the interior space (11) of the cartridge (1) in the area of the contact surface between the inner side of the side wall (12) and the outer side of the piston (2).

23. A system comprising a cartridge (1) according to one of claims 1, 9 or 15, and a piston (2) according to claim 18.