EP0807587B1 - A bag made of a flexible packing material - Google Patents

Description

The present invention relates to flexible film-coated bags Packaging material with a tear zone.

It is known to fill foods into bags, such as tubular bags, and the bag to close by sealing. The removal of the contents of the bag can, for example by tearing open the tubular bag. Depending on the type of packaging material the tear process is difficult. In particular flexible packaging materials stretchable or tough plastics are difficult to tear open and the contents remove. This is why a scribing aid is very often stamped on a sealed seam. In order to At most, the bag can be opened, but its contents can often not be opened remove cleanly or the bag has to be torn apart beyond the marking aid become what is often very difficult for the consumer. It's also beautiful have been proposed, for example, tubular bags with a tear strip Mistake. This tear strip can be pulled off over the circumference of the bag, the packaging material divides and the bag is thus opened. However, this is a very complex process because the tear strip in the layered building of the Packaging material must be installed.

A printed packaging film for packaging is known from US Pat. No. 5,316,209 of angular objects. The packaging film is with a overlapping seam is wrapped around the object and the printing controls the adhesion the overlapping seam on the packaging film. With a tear-open aid in the form a cut in the overlapping seam and the controlled adhesion should make it easy Opening the packaging can be achieved.

US Pat. No. 1,578,066 describes a packaging for butter, which is to be packaged Well encased in a cardboard box with perforations as predetermined breaking points is. Unperforated wax paper is wrapped around the box.

The object of the present invention is to provide a bag that can be used in any Location and advantageous in an edge area, contains attachable tear aid and the bag can be opened easily, the contents of the bag being released in this way is that the content can be removed without further manipulation of the opening.

According to the invention this is achieved in that the tear zone weakened in Form of a cut, a perforation or a notch in the packaging material and the area of weakening is covered with at least one film-forming mass is and after the packaging process a content is protected by the bag and for Removal of the contents of the bag a pulling or kinking movement of the layered film Mass breaks open and at the severing of the pouch releases the contents or the overlaid film-forming mass breaks open and the perforation or notch tears open and the bag releases the contents.

Flat bags, sealed edge bags, for example Space bag or tubular bag understood. Sealed edge bags and are preferred Tubular bag. As flexible packaging material, also called packaging materials, packaging materials, packaging foils etc., can use essentially all known flexible packaging materials become. The packaging materials should be machine-compatible, i.e. for the use be suitable on packaging machines. Packaging materials include such made of paper, optionally covered with barrier layers and / or with plastics or made of Cellular glass or packaging materials containing aluminum foils, such as with sealing layers and occasionally additional plastic layers provided with aluminum foils or packaging materials made of plastic foils or of plastic foils, which on one or both sides with Paper or metal foils are coated or packaging materials made of plastics, which is a barrier layer such as a plastic barrier layer, ceramic barrier layer or a contain metallic barrier layer.

Examples of plastics which can be used are polyolefins, such as polyethylenes or polypropylenes, Polyamides, polyvinyl chloride or polyester etc., each as a mono film or as a film composite or using different plastics in a composite as a multilayer Foil composites are used. There can be barrier layers between at least two layers such as. Ethyl vinyl alcohol barrier layers, or ceramic resp. vitreous or metallic barrier layers may be arranged. The plastic films or film composites can have a thickness of, for example, 10 to 100 μm, preferably 30 to 50 μm.

The packaging material can be coated on one or both sides, preferably on the side facing inwards in the bag produced therefrom, with a sealing layer, for example a sealing lacquer or a sealing film made of, for example, polyolefins, such as polyethylene. For example, for impermeable heat-sealed bags, a sealing layer containing 6 to 7 g / m ² sealing wax is sufficient.

The packaging material is advantageously used as continuous or roll goods.

On the packaging material, there will be an opening in the area of the tear zone provided for the bag Weakening attached. The weakening of the packaging material can be mechanical, for example by cutting knife, chemically e.g. by solvent, thermally, e.g. by laser beams, in the form of a cut, a perforation, a notch, etc. be made. The severing is preferred. The weakening can be straight forward or be curved and the weakening can be designed such that it Pouch made of flexible packaging material around the entire circumference or extends part of the circumference of the respective bag.

The area of weakening on the bag according to the invention is film-forming Mass covered. With the area of weakening, not only does the weakening itself become special also the adjacent parts of the packaging material, for example the area between 2 and 20 mm, preferably 5 and 10 mm, adjacent to the weakening, understood.

The bag according to the invention can only weaken with the film-forming area Mass be coated, but such a bag is advantageous completely with the film-forming Mass coated. The film-forming mass in particular represents the printing on the Bag.

In an advantageous embodiment, the film-forming mass is thicker in the region of the weakening than in the rest of the bag. The film-forming mass can be a Layer or a plurality, for example two, three, four, five, six etc. layers, about film-forming masses. The film-forming mass covers and closes the previously applied weakening and gives the packaging material in the area of Weakening again a tensile strength.

The film-forming mass, or the total amount when using a plurality of layers of film-forming masses lying one above the other, can advantageously be in the range of the weakening in amounts of 2 to 8 g / m ² , expediently 3 to 6 g / m ² and advantageously 3.5 to 5 g / m ² applied. Outside the weakening range, the film-forming mass can be applied, for example, in amounts of 1 to 7 g / m ² , expediently 1 to 5 g / m ² and advantageously 1 to 4 g / m ² .

To produce a film-forming mass, for example, paint colors can be made from volatile Constituents, such as solvents, and non-volatile constituents, such as film formers, resins, Plasticizers, auxiliaries, dyes, pigments, fillers etc. are used. Printing inks are preferred as film-forming compositions containing dyes or pigments, Solvents, fillers, other additives and binders. Are advantageous as binders Resins, varnishes, nitrocellulose, polyamides, vinyl resins, rosins, maleate resins, Shellac, etc. The paint colors are especially printing inks and can be by means of a Printing machine as printing on the weakened flexible packaging material be printed on. The printing represents not only the film-forming mass, but also at the same time also the decorative, and occasionally also informative, printing for the bags. The printing on the packaging material can be printed on the outside of a bag or on the inward-facing side or on both sides.

As a film-forming mass, substances can also be converted into a plastic form, as softened or melted and on the packaging material, on the outside of a bag or on the inward-facing side or on both sides, as a film.

The film-forming composition can be applied by an extrusion coating. to Extrusion coating is suitable, for example, polyolefins, such as polyethylenes or polypropylenes, or materials containing polyvinyl chloride.

Coatings by means of hot-melt compositions, also hot-melt coating compositions, are also used with film-forming compositions called includes. These are, for example, at normal temperature solid, viscoelastic or viscoplastic materials, preferably based on Resins, waxes, thermoplastics and elastomers, possibly with the addition of fillers, antioxidants, Lubricants and the like, which when heated after passing through a thermoplastic Transition into viscous or low-viscosity melts.

The film formation on the packaging material by means of the film-forming masses can also with chemically drying paints. The chemically dried paints contain cross-linked macromolecules by chemical reaction and thereby in particular can be obtained by polymerization.

The film-forming compositions can also be films, in particular low tensile strength or high Brittleness, be. The thicknesses of the foils can e.g. from 5 to 20 µm. Preferred foils can contain polyolefins, such as polyethylenes or polypropylenes, polyesters or polyamides. The films can on the packaging material, on the outside of a bag or on the inward facing side or on both sides, whereby the adhesion of the film or films to the packaging material by means of laminating adhesive and / or adhesion promoters, if necessary with the additional use of corona, flame, Plasma or ozone treatment can be done. For example, the film, in particular have sealing properties when used on the inside of the bag. The film then also represents a sealing layer. The film can also, as one further film-forming mass arranged over the printing varnish on the packaging material his.

If on the outside and the inside of the packaging material film-forming masses are attached, these can be the same or different.

The materials of the film-forming compositions are expedient and physiologically harmless approved for food packaging.

Further examples of arrangements of film-forming masses on the packaging material are sealing waxes, e.g. from polyolefins, such as polyethylenes, which are attached to the printing ink become. The film-forming composition is preferably on the outside of the bag Page. The film-forming mass can also be directed towards the inside of the bag Side attached. It can e.g. is the ink of a counterprint. Another film-forming mass can be formed on the printing ink of the reverse printing a sealing wax arranged. The packaging material can also be on the bag a layer of a film-forming mass, e.g. a printing varnish, and contain a sealing wax on the inside of the bag.

The present invention also relates to a method for producing a bag according to the present invention Invention. The method can advantageously be carried out in such a way that the flexible Packaging material a weakening is attached and then the weakening is covered by at least one film-forming mass.

The above-mentioned lacquers, printing inks, extrusion layers, Hot melt masses and etc. are used. Usually acts it is liquid resp. melted paint systems. The application of the film-forming masses can, for example, by centrifuging, spinning, flooding, pouring, rolling, spraying, Brushing, printing, extruding, etc. are carried out. Usually it acts flexible packaging materials are endless, which is why coating processes such as extrusion, spraying, rolling, printing or pouring in particular to offer.

In a particularly preferred method, the flexible packaging material is combined in one Provide the printing unit with the weaknesses and then the printing with Printing varnishes made as a film-forming mass. This process becomes flexible Packaging material in a printing press, for example in a high-pressure, gravure, Offset printing and in particular flexographic printing machine performed. Examples of printing machines are header printing units, multi-cylinder, single-cylinder, in-line, flexo and vario printing machines or combinations thereof, such as Flexographic and gravure printing machines. Appropriately in the area of the printing cylinder, before the start of printing, or in the case of multi-cylinder The weakening is advantageously achieved by machines in the area of the first impression cylinder a cutting unit attached to the flexible packaging material. Then it becomes flexible Provide the packaging material with the intended pressure, including the weakening is overprinted and the printing varnish closes the weakening. The printing varnish application e.g. guided such that the total thickness of the printing varnish in the area of weakening is larger than in the rest of the flexible packaging material. By means of the register regulation the printing processes can be carried out accurately and in addition to one The printed image can in particular be the weakening and the area around the weakening can be exactly hit by the printing varnish.

Present bags made of flexible packaging material can be used for food packaging powdery to firm consistency. A preferred use lies in the packaging of chocolate bars, starchy foods, fatty foods, or food preparations in the form of mixtures Chocolate with starch and / or fatty foods, all food preparations advantageous in the form of bars.

The packaging of chocolate bars and the like is preferred because in the opening process in in this case the chocolate bar as a repository for tearing the bag open serves.

If the bags are made of tube material, the bags each end a cross seam seal on or, if the bags are made of flat material, the bags have a longitudinal seam seal and a transverse seam seal at the end. The Seams can be sealed by cold sealing, heat sealing or by gluing.

The weakness is in the packaging of chocolate bars, for example advantageous in one of the two end regions of the bag, i.e. approx. 10-30 mm from the end of the bag, which is finished with a cross seal seam. Tubular bags with are particularly preferred a longitudinal seam seal and terminal transverse seam seals. If the bag runs along the When the weakening is torn open, the tear continues up to a maximum of the entire bag circumference around, but the longitudinal seam sealing prevents tearing. At the The longitudinal end and the longitudinal seam seal catches the kinked end of the bag. The contents of the bag can now be easily pushed out or directly from the packaging be consumed, the kinked piece of bag over the longitudinal seam with the remaining bag remains connected and no piece of bag to be disposed of or dropped to the floor forms.

FIGS. 1 to 6 explain the present invention in more detail by way of example.

Figure 1 shows schematically the production of a tubular bag.

Figure 2 shows schematically the view of a tubular bag.

Figures 3, 4 and 5 show another tubular bag from the front and back, as well as in the torn condition.

FIG. 6 shows a section through the packaging material in the area of a weakening.

According to Figure 1, the packaging material 10, which is already with the weaknesses and, for example, overpainting over the weakenings in the form of a multi-color print is provided, unrolled from a supply roll and fed to the packaging process. The arrow 11 indicates the product insert and the product insert is continuous the longitudinal seam seal 12 and the transverse seam seal 13, respectively a packing unit 14 is created. A cutting device 15 divides the material into tubular bags 16 with the transverse seams 17 and the longitudinal seam 19.

The tubular bag 16 is shown in FIG. The longitudinal seam 19 is located on the back and the tubular bag 16 is closed at both ends with transverse seams 17. by broken the weakening 18 is indicated, which is in the region of one end of the tubular bag 16 is located and is covered with, for example, a printing varnish.

Figures 3 and 4 show another tubular bag 16 with the transverse seams 17 on both Ends and the longitudinal seam 19. In Figure 4 is the weakening 18, which is below the print pattern generated by printing varnish is shown, dash-dotted lines. Will the Pack, for example by gripping the pack at the transverse seams 17 and by pulling apart stressed in tension, the pack separates along the weakening 18 the film material tears on and by pulling and, for example, folding at the same time further, generally along a tear line 20, which is shown in dotted lines in FIG. 3. The tear line 20 ends at the longitudinal seam 19, since there is a material accumulation or. material thickening was created by the folding and sealing. This is the tubular bag 16 along its circumference, except for the area of the longitudinal seam 19 and the contents can be easily removed, for example by pushing it out from the end. The two Parts of the tubular bag 16 hold together with the longitudinal seam 19 and can then be disposed of together.

Figure 5 shows the tubular bag 16 with the transverse seams 17 and the longitudinal seam 19 in torn Shape. The kinked bag part 27 is over the packaging material of the longitudinal seam 19 connected to the rest of the tubular bag 16. The tearing took place along the Weakening 18 and continued over the tear line 20 to the longitudinal seam 19. The content 26, e.g. a chocolate bar, the tubular bag 16 can now be easily removed or directly be consumed out of the pack.

FIG. 6 shows a section through the packaging material 10 in the area of the weakening 18. The weakening 18 was carried out, for example, on a plastic film 21 and the weakening 18 represents a severing of the plastic film Plastic film 21 is a multi-layer on the outside of the bag, in the Usually multi-colored, printing with the printing varnishes 23, 24 and 25 attached. When designing an additional layer of a was in the area of the weakening 18 of the printed image Printing varnish 24 applied, whereby the total thickness of the printing varnish layer compared the rest of the packaging material 10 increased and the weakening safely covered, closed and the packaging material 10 is again given a tensile strength. occasionally, can the packaging material 10 on the side facing inward on the bag Sealing layer 22, in particular a sealing wax, may be attached. The sealing wax 22 serves primarily for later sealing of the seams, but the printing varnish 23, 24, 25 in its Support effect.

Claims (12)

1. Bags made of a flexible packaging material coated with film-forming materials and comprising a tear zone, characterised in that the tear zone is a weakened part (18) in the form of a cut, perforation or notch in the packaging material (10), the region of the weakened part (18) is covered with at least one film-forming material (23, 24, 25), after the packaging process, the contents (26) are protected by the bag (16) and, in order to remove the contents (26) of the bag (16), the covering film-forming material (23, 24, 25) is broken by a pulling or folding movement and the bag (16) provides access to its contents (26) at the cut or the covering film-forming material (23, 24, 25) is broken and the perforation or notch torn and the bag (16) provides access to its contents.
2. Bag according to claim 1, characterised in that the film-forming material or materials (23, 24, 25) is/are thicker in the region of the weakened part (18) than in the remaining region of the bag (16).
3. Bag according to claim 1, characterised in that the film-forming material or materials (23, 24, 25) is/are applied in the region of the weakened part (18) in quantities of 2 to 8 g/m², expediently 3 to 6 g/m² and advantageously 3.5 to 5 g/m².
4. Bag according to claim 1, characterised in that the weakened part (18) in the form of a perforation or (...) extends over all or part of the circumference of the bag (16).
5. Bag according to claim 1, characterised in that the weakened part (18) is applied over the contents (26) of the bag in an edge region.
6. Bag according to claim 1, characterised in that the packaging material contains at least one film-forming material (23, 24, 25) in the form of printing by means of paints, preferably on the side of the bag (16) directed towards the outside.
7. Bag according to claim 1, characterised in that the packaging material contains at least one sealing layer (22), preferably a sealing layer (22) directed towards the inside of the bag.
8. Bag according to claim 1, characterised in that the bag (16) is provided at its ends with transverse seam seals (17) or that the bag (10) has a longitudinal seam seal (19) and end transverse seam seals (17).
9. Process for the production of a bag according to claim 1, characterised in that a weakened part (18) is applied to the flexible packaging material (10) and the weakened part (18) is covered by means of at least one film-forming material (23, 24, 25).
10. Process according to claim 9, characterised in that the weakened part (18) is applied to the flexible packaging material (10) in a printing machine and the weakened part (18) is covered in the printing machine by printing by means of at least one layer of print varnish (23, 24, 25).
11. Use of the bag according to claim 1 for packaging foodstuffs of a pulverulent to solid consistency.
12. Use of the bag according to claim 11 for packaging bars of chocolate, starch-containing foodstuffs, fat-containing foodstuffs or mixtures of chocolate and starch-containing and/or fat-containing foodstuffs.

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