AT519653B1 - Composite film with a mineral oil barrier - Google Patents

Abstract

The invention relates to a composite film (11) having at least one base layer (1), a laminating layer (2) and a barrier layer (3). The base layer (1) forms a first sealing surface (8) of the composite film and consists at least predominantly of a preferably oriented polyolefin. The laminating layer (2) connects the base layer (1) directly or optionally by means of further intermediate layers (4) to the barrier layer (3). The barrier layer (3) consists at least predominantly of a polyester or a polyamide. At least partially a sealing layer (5) of a sealing material is applied to the barrier layer (3), wherein the sealing layer (5) forms at least one second sealing surface (9) of the composite foil sealable with the first sealing surface (8) of the base layer (1).

Description

description

VERBUNDFOLIE WITH A MINERAL OIL BARRIER

The invention relates to a composite film having at least one base layer, a laminating layer and a barrier layer, wherein the base layer forms a first sealing surface of the composite film and at least predominantly consists of a preferably oriented polyolefin and wherein the laminating the base layer directly or optionally by means of further intermediate layers the barrier layer connects, a pouch packaging made of the composite film and a method for producing the pouch packaging.

Furthermore, the invention relates to a method for producing a composite film, wherein a base layer, which is at least predominantly made of a preferably oriented polyolefin, is connected by means of a laminating directly or optionally by means of further intermediate layers with a barrier layer.

Composite films for the manufacture of pouches for food, such as cereals, crisps or the like, generally have a layered structure which typically comprises two layers of oriented polypropylene. Such packaging materials, however, have an insufficient barrier property to some of the quality-damaging and / or harmful substances, in particular to mineral oil residues, such as may be contained in packaging paper made from waste paper. In order to improve the barrier properties to these materials, polypropylene barrier plastics ("High Barrier Polypropylene") have been developed. However, these are very expensive and significantly increase the overall cost of the packaging material.

An important feature of these composite films is their sealability, whereby it is necessary for the manufacture of many types of bags that the composite film in any combination, i. E. Both top to top, and bottom to bottom and bottom to top should be self-sealable.

EP 0613773 A1 discloses a multilayer composite film having the following layer structure: 40 μm biaxially stretched, white-opaque polypropylene film; 2 μm polyurethane adhesive; 15 μm coextrudate: polyamide 6 / ethylene vinyl alcohol copolymer / polyamide 6; 2 μm polyurethane adhesive; 75 pm sealing layer of ethylene vinyl acetate copolymer.

The subject invention has for its object to provide a thin, inexpensive and easy to produce composite film that combines good barrier properties with an advantageous sealability.

According to the invention, these and other objects are achieved by a composite film of the type mentioned, in which the barrier layer consists at least predominantly of a polyester or a polyamide, wherein at least partially a sealing layer of a sealing material is applied to the barrier layer and wherein the sealing layer at least a second sealing surface of the composite foil which can be sealed with the first sealing surface of the base layer is formed, wherein the free surface of the sealing layer can be sealed with respect to the free surface of the base layer with a sealed seam strength of at least 0.5 N / 15 mm. The use of the barrier layer of polyester or polyamide provided with the sealing layer creates a functional barrier against mineral oils in a cost-effective and simple manner. The composite film is therefore particularly suitable for use in food packaging.

The term "predominantly consisting of" means in connection with the subject description that in the corresponding layer no material is present in a greater proportion by weight, as the so-called substance. The term therefore also includes, in particular, layers which have the abovementioned substance in an absolutely predominant proportion (that is to say more than 50%), and also layers which consist essentially exclusively of said substance. "Substantially exclusive" means that at most only adjuvants, such as plasticizers, stabilizers and / or fillers, are included in the usual addition levels in the layer.

By the free surface of the sealing layer with respect to the free surface of the base layer with a sealed seam strength of at least 0.5 N / 15 mm is sealable, this seal seam strength allows the production of bag packaging, while safely sealed for transport and storage, but by the user nevertheless are openable. As is known to the person skilled in the art, the seal seam strength is usually determined in accordance with DIN 55529. The values given here are based on this standard.

Advantageously, the sealing layer can be applied only in sealing areas of the composite film on the barrier layer. This can reduce the material costs.

In an advantageous embodiment, the sealing layer may have a heat-sealing lacquer, preferably based on ethylene-vinyl acetate. Such sealing layers can be easily applied by means of simple and proven methods.

In a further advantageous embodiment may be applied to the barrier layer and / or on the base layer over the entire surface or part of a pressure layer. The print layer does not affect the sealability, since the sealant layer can either be applied to non-printed areas or applied in a subsequent step on the print layer, for example, inline in a downstream printing process.

Advantageously, the thickness of the base layer between 3 pm and 50 pm, preferably between 10 pm and 30 pm, and the thickness of the barrier layer may be between 6 pm and 50 pm, preferably between 8 pm and 25 pm. As a result, depending on the application requirements, very thin composite films, for example, even with thicknesses of less than 20 pm, produce, yet have a high strength, have barrier properties to mineral oils and are sealable on both sides.

In an advantageous embodiment, the laminating layer can be a solvent-containing, solvent-free or aqueous laminating adhesive, preferably with a layer thickness of 1 g / m2 to 6 g / m2, or an extrusion laminating adhesive, preferably with a layer thickness of 10 g / m2 to 30 g / m2. This makes it possible to achieve a thin and stable film composite. The laminating layer may advantageously have a polyurethane-based laminating adhesive.

A preferred embodiment of the invention may provide that the base layer and / or the barrier layer is a functionally treated surface, in particular a coating, preferably with alumina, silica, or with a barrier coating, preferably based on polyvinyl alcohol (PVOH), and / or a metallization, preferably with aluminum. The coating can serve the visual and / or light protection, offers a wide scope for the external design and allows the implementation of optical effects.

Advantageously, the barrier layer at least predominantly of polyethylene terephthalate (PET) exist. In contrast to the polypropylene commonly used in the art in this technical environment, PET offers excellent barrier properties to mineral oils (both MOSH and MOAH). Above all, due to the poor sealing properties of PET, however, this substance has hitherto scarcely been used for the purposes mentioned at the outset since it has hitherto not been possible to produce cost-effective composite films with the properties required for the other processing.

The invention further relates to a bag package made from a composite film described above. The packaging is inexpensive and particularly suitable for packaged goods that are receptive to mineral oils, such as potato chips, cereals, or similar products.

Furthermore, the invention relates to a method for producing such a bag packaging, which is formed from a composite film according to the invention described above and sealed to seal areas. The production can thus be done with the existing and proven machines.

The objectives of the invention are further achieved by the aforementioned method for producing a composite film, wherein the barrier layer consists at least predominantly of a polyester or a polyamide and wherein applied to the barrier layer at least partially an outer sealing layer of a sealable with the base layer sealing material becomes.

In an advantageous manner, it can be provided that the sealing layer is applied to the barrier layer only in sealing regions of the composite film. In addition to the economical use of the materials used, this allows an advantageous product design of the packaging.

Furthermore, for this purpose, in a preferred embodiment of the invention on the barrier layer and / or on the base layer over the entire surface or part of a print layer are applied.

In a further preferred embodiment, the sealing layer can be applied in a printing process, which allows the production of the composite film according to the invention using conventional printing machines.

Preferably, according to the invention further, the printing layer and the sealing layer can be applied in a same production line, whereby the manufacturing process can be optimized and the application of the sealing layer can be integrated into the printing process.

For the laminating layer, a solvent-containing, solvent-free or aqueous laminating adhesive having a layer thickness of 1 g / m 2 to 6 g / m 2 or an extrusion laminating adhesive having a layer thickness of 10 g / m 2 to 30 g / m 2 can advantageously be used , A laminating adhesive based on polyurethane may preferably be used for the laminating layer.

In order to enable a further advantageous embodiment, the base layer and / or the barrier layer with a functionally treated surface, in particular a coating, preferably with alumina, silica or with a barrier coating, preferably based on polyvinyl alcohol (PVOH), and / or a metallization, preferably with aluminum.

Furthermore, according to the invention, the barrier layer may advantageously be produced at least predominantly from polyethylene terephthalate (PET).

The composite film produced according to the invention and the packaging produced therewith are comparable in terms of manufacturing and material costs with known in the art solutions and also provide excellent barrier properties.

The subject invention will be explained in more detail with reference to Figures 1 to 4, which show by way of example, schematically and not limiting advantageous embodiments of the invention. FIG. 1 shows a schematic representation of the layer structure of the invention. FIG

2 shows a further schematic representation of the layer structure of an embodiment of the composite film according to the invention; FIG. 3 shows a schematic representation of a production process according to the invention; and [0032] FIG. 4 illustrates the production of pouches according to the invention.

Fig. 1 shows the layer structure of a composite film 11 according to the invention in a schematic sectional view, wherein the layer thicknesses are not to scale for the sake of illustration.

The composite film 11 has a base layer 1, which forms a (in the illustration of FIG. 1 at the bottom) first outer surface 8 of the composite film 11. The base layer 1 consists of a polyolefin, preferably of polypropylene, which offers advantageous properties as an inside of a bag packaging for food products due to its advantageous sealing capabilities, its strength and its food compatibility. The base layer 1 is preferably oriented, i. the film used as the base layer 1 is stretched in the machine direction and / or transversely before being laminated, whereby this layer simultaneously becomes thinner and stronger. With a base layer 1 of mono- or biaxially oriented polypropylene, for example, it is particularly advantageous to produce thin and strong composite films. The base layer may, for example, have a thickness of between 3 pm and 50 pm, a thickness of between 10 pm and 30 pm being a preferred embodiment.

On the base layer 1, a barrier layer 3 is laminated, wherein the laminating adhesive used forms a laminating layer 2. For example, a solvent-containing, solvent-free or aqueous laminating adhesive can be used as the laminating adhesive for conventional laminating methods, whereby a very thin layer thickness, for example between about 1 g / m 2 to about 6 g / m 2, can be achieved. For the laminating layer 2, in particular a laminating adhesive based on polyurethane can be used. Further examples of advantageously usable laminating adhesive systems are laminating adhesives based on polyacrylic acid esters and polymethacrylic acid esters.

On the other hand, the lamination can also be carried out as extrusion lamination, whereby proven extrusion Kaschierklebersysteme can be used. Extrusion lamination allows the production of laminating layers having a favorable layer thickness in the range of about 10 g / m 2 to about 30 g / m 2. Extrusion laminating adhesives which can be used are polyolefin-based extrusion laminating adhesives to which any known additives have been added.

The barrier layer 3 is preferably made of a polyester or a polyamide, polyethylene terephthalate is a particularly preferred material for the barrier layer 3. In order to provide a good barrier property, in particular to mineral oils, the barrier layer may for example have a thickness in the range from 6 pm to 50 pm. The required thickness depends on the remaining materials used and layer thicknesses in the composite film. A thickness between 8 μm and 25 μm generally already provides sufficiently good barrier properties and can therefore be regarded as a preferred thickness range.

On the barrier layer 3, a sealing layer 5 is applied, whose free surface forms a second outer surface 9 of the composite film. As the material for the sealing layer 5, it is possible, for example, to use a hot-sealing lacquer (for example based on ethylene-vinyl acetate) applied with at least one application layer, which is provided with a sealability relative to the first outer surface 8 of the base layer 1. The heat-sealing lacquer is chosen so that a seal seam strength of at least one outer surface 8 to the second outer surface 9 of at least 0.5 N / 15 mm (measured according to DIN55529) can be achieved. As a result, an advantageous bursting pressure can be achieved, with an overpressure of +0.2 bar (in addition to the atmospheric pressure) being sufficient for numerous applications as the lower limit for the bursting pressure.

The first outer surface 8 and the second outer surface 9 are thus matched with respect to their sealability. As a result, in addition to sealing from the first outer surface 8 to the second outer surface 9, both the first outer surface 8 of the composite foil 11 and the first outer surface 8 of the same or a corresponding composite foil 11 can be sealed, as well as the second outer surface 9 to the same or another identically formed second outer surface 9th

The sealing layer 5 may have a layer thickness of about 1 pm to about 8 pm, a balance of sealing properties, film thickness and material costs

Layer thickness of about 2 microns to about 6 microns appear advantageous.

The sealing layer 5 can be applied in any manner to the barrier layer 3, wherein application by means of a printing process is advantageous. The application in a printing process allows both full-surface and partial-area application of the sealing layer 5. If desired, the sealing layer 5 can be applied in several layers, for example by means of several successive printing operations.

In addition to the basic layer structure described above (which is regarded as a particularly advantageous embodiment due to its simple layer structure), the base layer 1 may optionally have further single- or multi-layer intermediate layers 4, for example, advantageous properties of intermediate layers consisting of certain materials with the advantages to combine the composite film according to the invention. The intermediate layer 4 may consist, for example, of paper, metal, in particular aluminum, or a plastic and, depending on the material and requirement, may be laminated onto the base layer 1, extruded or coextruded together with the base layer 1. The intermediate layer 4 may optionally be applied after stretching or orienting the base layer 1 thereto, or it may be stretched or oriented together with the base layer. It is also possible to combine stretching or orientation steps, which are carried out independently of one another on the base layer 1 and / or the intermediate layer 4, with stretching or orientation steps which, after lamination, are carried out on the composite of the base layer 1 and the intermediate layer 4 become.

The intermediate layer 4 can also form a functionally treated surface 10, as exemplified in FIG. 2 and described below. In this case, the intermediate layer may be formed, for example, as a coating, preferably with aluminum oxide or silicon oxide, and / or a metallization, preferably with aluminum.

The intermediate layer 4 may for example also be an "inner" printing layer or have such.

The barrier layer 3 may also have one or more intermediate layers 4 ', 4 ", the features described above for the intermediate layer (s) 4 of the base film 1 also being applied to the intermediate layers 4', 4" of the barrier layer 3 can.

The intermediate layer 4 "between barrier layer 3 and sealing layer 5 shown in FIG. 1 can be, for example, a full-area or partial pressure layer applied before the application of the sealing layer 5. However, it is also possible to provide a printing layer applied to the barrier layer 3 on the side of the laminating layer 2 (this would correspond to the intermediate layer 4 'illustrated in FIG. 1). Depending on the printing method, the material of the printing layer can be selected, for example, from gravure printing inks, flexographic printing inks and printing inks.

FIG. 2 shows a further example of an advantageous embodiment of the layer construction of the composite film 11 according to the invention. The structure of base layer 1, laminating layer 2 and barrier layer 3 corresponds to the structure described with reference to FIG. 1, wherein the composite film 11 of FIG 2 may also be provided with the same features (in particular intermediate layers 4, 4 ', 4' ') as described above in connection with FIG.

The base layer has a functionally treated surface 10 on the side facing the laminating layer 2. This functionally treated surface may be, for example, a coating with alumina or silica, or a metallization, preferably with aluminum.

In contrast to FIG. 1, the composite film 11 shown in FIG. 2 has a pressure layer 7 applied over part of the area, and also the sealing layer 5 is applied over part of the area only in a sealing region 6. The sealing layer 5 and the printing layer 7 are arranged overlapping, the sealing layer 5 covering the printing layer 7 in the overlapping area so that the composite film 11 forms the second outer surface 9 in the entire sealing area 6, so that this outer area 9 has the desired sealing properties in the entire sealing area 6 ,

Fig. 3 shows an exemplary and schematic representation of an apparatus for producing the composite film 11 according to the invention, wherein the apparatus is a method for producing the composite film 11 according to the invention in a single production line 13 is executed. The layer structure that results during the individual production stages in the production line 13 is shown by way of example and schematically below the device.

As a production line 13, a device is considered in connection with the subject disclosure, with an intermediate or end product is made from one or more starting materials substantially without interim storage steps. In connection with FIG. 3, this corresponds to the processing steps which lie between the film wound on a first roll 14 for the base layer 1 and the finished composite film 11 rolled up on a second roll 15.

The film for the base layer 1 is unrolled from the first roller 14 and fed to a laminating device 16, where it is laminated by means of the laminating layer 2 with the barrier layer 3. The laminating device 16, which is shown only schematically in FIG. 3, can be any type of laminating device 16.

In addition (not shown here) devices for orientation of the films may be provided, in particular, an orientation in the machine direction, an orientation transverse to the machine direction or a biaxial orientation can be achieved by appropriate stretching. The orientation can either be introduced individually into the individual precursor films (i.e., the film of the base layer 1 and / or the film of the barrier layer 3) before lamination, or the laminated film composite can be stretched and oriented after lamination.

The base layer 1 and the barrier layer 3 can each be supplied as a film precursor of the laminating device 16 (as shown), but it is also possible to apply the barrier layer 3 and the laminating layer 2 to the base layer 1 in a coextrusion process. Optionally, the base layer 1, the laminating layer 2 and the barrier layer 3 may be coextruded in a co-extruded manner, or this layer combination may be provided as a precursor on the first roll 14, in which case no separate laminating device 16 would be required in the production line 13 (ie Laminating and printing is done in two separate steps).

The laminating device 16 are a first printing unit 17 and a second printing unit 18 downstream. In the first printing unit 17, a printing layer 7 is applied to the free surface of the barrier layer 3. The printing layer 7 may be over the entire surface, or as shown schematically in FIG. 3, part of the area, leaving unprinted areas.

In the second printing unit 18, the sealing layer 5 is applied, it being possible to provide that with the printing unit 18, the sealing layer 5 is selectively applied only in certain sealing regions 6.

The two printing units 17, 18 can independently use any suitable printing techniques, with flexographic printing and / or intaglio printing in particular being preferred in industrial applications. Other printing units for additional colors and / or printing material and / or sealing layers may be provided as needed.

Alternatively to the order shown in Fig. 3, the individual layers can also be printed before laminating. For example, in a reverse printing process, first the barrier layer 3 or the base layer 1 can be printed, then the heat sealing lacquer is applied and then the lamination takes place.

After printing, the finished composite film 11 can be wound onto the second roll 15 for storage or transport. Alternatively, the composite foil can be further processed inline immediately.

FIG. 4 schematically shows the production of a bag package 12 using a composite film 11. The devices with which such pouches 12 can be made from tape sheets are known and therefore need not be described herein. 4 therefore serves merely to explain how the sealing regions 6 can be advantageously arranged on the composite film 11 according to the invention.

The lateral edges of the composite film supplied as a strip material are hammered towards the center, superimposed and sealed together at a longitudinal sealing seam 19, so that the composite film forms a tubular configuration. In order to form individual bags from the tubular configuration, transverse sealing seams 20 are introduced transversely to the longitudinal extent of the tube. The pouch packaging 12 created thereby may then be cut from the pouch tube either adjacent to and parallel to the transverse seal 20 to provide an open pouch which may be filled and sealed in a later step.

In other production processes, the bags are also filled at the same time as the preparation described. In this case, the longitudinal sealing seam 19 is continuously produced and the resulting tube is closed at regular intervals with a transverse sealing seam 20 (as bottom seam). Then the bag tube closed at the bottom is filled from the forming shoulder and closed with the next transverse seam 20 (as a top seam). The formed during sealing top seam is also the bottom seam of the subsequent bag. The "chain" of filled bag packages 12 can then be cut in the middle of the transverse sealing seams 20, as indicated by the dash-dot lines in FIG. 4.

In Fig. 4, the composite sheet 11 is arranged so that the second outer surface 9 forms the outside of the bag package 12 and the first outer surface 8 is disposed on the inside of the bag package 12. In order to be able to seal the outer edges of the composite film web with one another at the longitudinal sealing seam 19 in order to produce the pouch packaging 12, two sealing regions 6 ', 6 "are provided at these edges. The first sealing region 6 'is located on the first outer surface 8, which in any case is completely sealable. On the other hand, the second sealing area 6 "is provided on the second outer surface 9, and was applied to the film only in the required area as a sealing layer 5 applied over the entire area.

Since in the region of the transverse sealing seam 20 the two surfaces to be sealed correspond to the first outer surface 8, it is not necessary to apply a sealing layer 5 here. However, for example, for the production of more complex bag shapes, such as laterally folded bags or block bottom bags, it may be necessary to provide sealing areas in other areas of the composite film 11, as indicated in FIG. 4 by the third sealing area 6 "arranged transversely to the feed direction. REFERENCE NUMBERS:

Base layer 1

Laminating layer 2

Barrier layer 3

Interlayers 4

Sealing layer 5

Sealing areas 6

Print layer 7 first outer surface 8 second outer surface 9 functionally treated surface 10th

Composite film 11

Pouch packaging 12

Production line 13 first roll 14 second roll 15

Laminating device 16 first printing unit 17 second printing unit 18 longitudinal sealing seam 19

Cross seam 20

Claims (20)

claims Composite film (11) having at least one base layer (1), a laminating layer (2) and a barrier layer (3), the base layer (1) forming a first sealing surface (8) of the composite film and consisting at least predominantly of a preferably oriented polyolefin and wherein the laminating layer (2) connects the base layer (1) directly or optionally by means of further intermediate layers (4) to the barrier layer (3), characterized in that the barrier layer (3) consists at least predominantly of a polyester or a polyamide, wherein the barrier layer (3) is at least partially provided with a sealing layer (5) of a sealing material and wherein the sealing layer (5) forms at least one second sealing surface (9) of the composite foil sealable with the first sealing surface (8) of the base layer (1) free surface of the sealing layer (5) with respect to the free surface of the base layer (1) with a sealing seam strength of at least 0, 5 N / 15 mm is sealable. 2. Composite foil (11) according to claim 1, characterized in that the sealing layer (5) is applied to the barrier layer (3) only in sealing areas (6) of the composite foil. 3. The composite film (11) according to claim 1 or 2, characterized in that the sealing layer (5) has a heat-sealing lacquer, preferably based on ethylene-vinyl acetate. 4. The composite film (11) according to any one of claims 1 to 3, characterized in that on the barrier layer (3) and / or on the base layer (1) over the entire surface or part of a pressure layer (7) is applied. 5. The composite film (11) according to any one of claims 1 to 4, characterized in that the thickness of the base layer (1) between 3 pm and 50 pm, preferably between 10 pm and 30 pm and that the thickness of the barrier layer (3) between 6 pm and 50 pm, preferably between 8 pm and 25 pm. 6. The composite film (11) according to any one of claims 1 to 5, characterized in that the laminating layer (2) a solvent-containing, solvent-free or aqueous laminating adhesive, preferably with a layer thickness of 1 g / m2 to 6 g / m2, or an extrusion Laminating adhesive, preferably with a layer thickness of 10 g / m2 to 30 g / m2. 7. The composite film (11) according to any one of claims 1 to 6, characterized in that the laminating layer (2) has a laminating adhesive based on polyurethane. 8. The composite film (11) according to any one of claims 1 to 7, characterized in that the base layer (1) and / or the barrier layer (3) has a functionally treated surface (10), in particular a coating, preferably with alumina, silica or with a barrier coating, preferably based on polyvinyl alcohol (PVOH), and / or a metallization, preferably with aluminum. 9. The composite film (11) according to any one of claims 1 to 8, characterized in that the barrier layer (3) consists at least predominantly of polyethylene terephthalate (PET). 10. From a composite film (11) according to any one of claims 1 to 9 produced bag package (12). 11. A method for producing a composite film (11), wherein a base layer (1), which is at least predominantly made of a preferably oriented polyolefin, by means of a laminating layer (2) directly or optionally by means of further intermediate layers (4) with a barrier layer (3) is connected, characterized in that the barrier layer (3) consists at least predominantly of a polyester or a polyamide, wherein on the barrier layer (3) at least partially an outer sealing layer (5) is applied from a sealable with the base layer sealing material. 12. The method according to claim 11, characterized in that the sealing layer (5) is applied only in sealing areas (6) of the composite film on the barrier layer (3). 13. The method according to claim 11 or 12, characterized in that on the barrier layer (3) and / or on the base layer (1) over the entire surface or part of a pressure layer (7) is applied. 14. The method according to any one of claims 11 to 13, characterized in that the sealing layer (5) is applied in a printing process. 15. The method according to any one of claims 11 to 14, characterized in that the printing layer (7) and the sealing layer (5) in a separate production line (13) are applied. 16. The method according to any one of claims 11 to 15, characterized in that for the laminating layer (2) a solvent-containing, solvent-free or aqueous laminating adhesive having a layer thickness of 1 g / m2 to 6 g / m2 or an extrusion laminating adhesive with a layer thickness of 10 g / m2 to 30 g / m2 is used. 17. The method according to any one of claims 11 to 16, characterized in that for the laminating layer (2) a laminating adhesive based on polyurethane is used. 18. The method according to any one of claims 11 to 17, characterized in that the base layer (1) and / or the barrier layer (3) with a functionally treated surface (10), in particular a coating, preferably with alumina, silica or with a barrier coating , preferably based on polyvinyl alcohol (PVOH), and / or a metallization, preferably with aluminum. 19. The method according to any one of claims 11 to 18, characterized in that the barrier layer (3) is made at least predominantly of polyethylene terephthalate (PET). 20. A method for producing a bag package (12), characterized in that from a prepared according to one of claims 11 to 19 (11) composite film, the bag package (12) is formed and sealed to seal areas (6). For this 3 sheets of drawings