MULTIPACK SHRINK FILM WITH INTEGRATED LABEL

Abstract

 The invention relates to a multipack shrink film (1) for a pack (10) of items (11), wherein the film (1) comprises at least substantially only one single plastic grade and a removable label (5) comprising a visual, machine-readable form. The label (5) is made of the same polymeric material as the film (1) and the label (5) is integrated into the film (1). The label (1) having an outer edge (6) formed by spaced-apart openings (7), which form a perforation which limits the label (5) in the film (1) and said openings (7) being spaced apart by a distance (12).

Description

[0001] The invention relates to a multipack shrink film for a pack of items, wherein the film comprises at least substantially only one single plastic grade and having a removable label comprising a visual, machine-readable form.

[0002] A multipack is a package that combines and/or contains multiple items or smaller packages. In this regard, multiple items may be grouped together to form a larger retail unit and provide a packaging handle for convenient transport of multiple items. A multipack for packaging a container may have a tamper-evident seal and reduces the environmental impact of secondary packaging.

[0003] Examples of products that are grouped into multipacks of containers may include beverage cans, water bottles or milk packaging units. In addition, snacks, toilet paper, cosmetics, batteries and other items are also grouped together as multipacks and tin cans.

[0004] Current, commercially available packaging, such as multipacks shrink films, made of plastic are often film laminates consisting of different layers that are assembled with regard to their application and function, such as polyolefins like polyethylene (PE) and/or polypropylene (PP), often also combined with other polymers to achieve the desired physical film properties.

[0005] Polyethylene has been used to produce food packaging films, food bags, stretch films, shrink films, bin liners and mailing bags. Conventional blown or cast polyethylene films are often used for flexible packaging as a single package or as a laminating film.

[0006] At the same time, the way in which plastic, and therefore packaging films, are currently produced and disposed of can be detrimental to the environment. The consequences range from CO₂ emissions to pollution of the oceans when disposed of improperly. To counteract this, the European Union wants to reduce the landfilling of plastic waste as part of its "Green Deal". By 2030, 55 % of plastic packaging waste is to be recycled.

[0007] To meet the challenges of recycling, the design of packaging must become increasingly sustainable. This can be done, for example, through the implementation and realization of more mono-material designs. The challenge here is to achieve the very different properties of a package, previously achieved by combining different layers of plastic with different material bases, with just one recyclable mono-material construction.

[0008] Multipack shrink film is a stretchable shrink film that can be applied precisely and without wrinkles to the materials to be packaged. The multipack shrink film offers enormous stability for the packaged bundle of different items, which is therefore easy to handle, both in logistics and in sales.

[0009] EP 1 343 700 B1 describes a combination of two or more packages placed side by side to form a unit, wherein the unit is shrink wrapped in two or more films on opposite film sides of the unit, wherein combination of two or more packages placed side by side to form a unit, wherein the unit is shrink wrapped in two or more films on opposite film sides of the unit.

[0010] US 7 328 550 B2 describes a method of packaging articles using pre-perforated heat shrink film comprising: creating a line of perforations in a sheet of heat shrink film; wrapping the sheet of heat shrink film around parallel groups of articles spaced from one another; enclosing the parallel groups of articles in the heat shrink film with the line of perforations between the parallel groups of articles, thereby forming a continuous film envelope having first and second open ends, the line of perforations being spaced from and intermediate the first and second open ends; conveying the enclosed parallel groups of articles in a conveying direction in an orientation such that the first and second open ends of the film envelope are substantially transverse to the conveying direction and the perforation line is parallel to the conveying direction; and applying thermal energy to the conveyed enclosed parallel groups of articles to weaken the continuous film envelope at the perforation line, the envelope then buckling at the perforation line and shrinking against the articles.

[0011] In EP 2 402 263 A2, a handle for carrying multipacks formed with a heat-shrinkable film tightly wrapped around ordered groups of full containers having upper parts projecting upwards and having upper reinforcing and flattening inserts to allow stacking of similar multipacks.

[0012] In France, it is a legal requirement that labels with a barcode can be removed from multipacks for the payment process at the checkout, allowing the multipack to remain in the shopping trolley. This is particularly advantageous for elderly and/or impaired shoppers.

[0013] Previously known labels of multipacks are usually made of polypropylene (PP), whereas the multipack shrink film is based on polyethylene. This is particularly disadvantageous in terms of recycling. In addition, several extra steps are necessary in the production of the multipacks in order to attach the label to the multipack using adhesive. The label is not loss-proof, so that the barcode of the label must also be printed on the multipack shrink film on the top.

[0014] The object of the present invention is to provide a multipack shrink film that overcomes the disadvantages of previous solutions. The multipack shrink film should be fully recyclable. In addition the film should meet all the requirements for the secure packing of items. The film should be produced ecologically with the low production costs and in an environmentally friendly manner.

[0015] According to the invention, this task is ensured by a multipack shrink film, a method and a use according to the subordinate main claims. Preferred variants can be found in the subclaims, the description and the drawings.

[0016] According to the invention, the label consists of the same polymeric material as the film, wherein the label is integrated into the film, wherein the label has an outer edge which is formed by mutually spaced openings, which form a perforation which limits the label in the film and wherein the openings are being spaced apart by a distance.

[0017] The label is advantageously made of the same polymeric material as the multipack shrink film, so that no problems arise with regard to the recycling of the packaging due to a non-uniform material base.

[0018] For this purpose, the single-grade polymeric material is based on polyethylene.

[0019] The label is advantageously integrated into the multipack shrink film, so that no additional work steps are required to apply the label. The label can also no longer be lost unintentionally. Furthermore, no adhesive is required to apply the label. This eliminates a number of steps in the production of previous multipack packaging solutions, which is particularly beneficial for the production process and the associated costs.

[0020] The label includes an imprint in the form of a visual, machine-readable form. For example, the imprint is designed as a barcode and contains information about the checkout process at a supermarket checkout.

[0021] In an alternative variant, the label includes an imprint for a special offer or a competition or a collectible picture.

[0022] The label has an outer edge that borders the label. This outer edge is formed by openings that are made in the multipack shrink film, for example by a laser perforation. This means that the label is still integrated into the multipack shrink film and can be removed from the multipack shrink film at the same time, for example for the checkout process at a supermarket checkout.

[0023] The openings thus form a material weakening that ensures easy removal of the label from the Multipack shrink film. Due to the defined spacing of the openings, the outer edge of the openings of the label is formed as a predetermined breaking point.

[0024] The openings are for example round and/or circular and/or rectangular and/or square and/or oval and/or trapezoidal and/or polygonal.

[0025] In a variant of the invention, the openings have a diameter or an equivalent diameter in a range of 0.1 - 0.5 mm, preferably in a range of 0.15 - 0.45 mm, in particular in a range of 0.2 - 0.4 mm. This means that the multipack shrink film is still very stable and does not shrink during the shrinking process, while at the same time sufficiently weakening the material to allow the label to be removed.

[0026] The equivalent diameter designates a substitute diameter in the case of a non-circular opening geometry.

[0027] The openings are spaced apart by a distance, specially the shortest distance, from the center of one opening to the center of the next opening, whereby the distance is in a range of 1.0 - 6.0 mm, preferably in a range of 1.5 - 5.5 mm, in particular in a range of 2.0 - 5.0 mm. Due to this, the multipack shrink film still has a high stability and does not show any cracks during the shrinking process. At the same time, material weakening is sufficiently ensured to allow easy removal of the label.

[0028] For example, the label is positioned on the top side in the middle of four items. Even after the label has been removed from the multipack shrink film, the items are still stably enclosed, in particular the closure openings of the items are stably enclosed, and can be transported safely.

[0029] At the same time, the removed label can also serve as a predetermined breaking point for opening the multipack shrink film, for example between the first two rows of items. This can be supported, for example, by making further openings between the first two rows of items.

[0030] In one variant of the invention, the openings have a distance to the printed barcode of more than 1.0 mm, preferably of more than 2 mm, in particular of more than 3 mm and/or of less than 10 mm, preferably of more than 8 mm, in particular of less than 6 mm. Due to this distance, the imprint remains advantageously machine-readable after removal of the label.

[0031] For example, the openings are arranged in a geometric figure around the machine readable form of the label imprint. The geometric figure may, by way of example, be formed as a rectangle or as a square or as a circle or as an oval or as a trapezoid or as superpositions formed therefrom.

[0032] For example, the openings are rimmed with molten polymer material.

[0033] In one embodiment of the invention, the openings have a border of fused polymeric material. The borders reinforce the openings so that they do not tear open in an uncontrolled manner. In this case, the borders are formed by the perforation process using a laser.

[0034] For example, the border of openings has an engagement opening for removing the label from the film. The engagement hole is larger than the other holes.

[0035] The outer edge has an engagement hole for removing the label from the film, the engagement hole having a long side with a range of 5 mm to 20 mm and having a short side with a range of 0.5 mm to 5 mm.

[0036] For example, the engagement opening is designed as an oval, so that a fingernail or a finger poked through the film can advantageously find a place. This makes it easy to separate the label from the multipack shrink film.

[0037] The Multipack shrink film not only has the advantageous design of the label, but is also a mono-material construction with convincing physical properties.

[0038] Shrinkage or the shrinking of plastics is understood to be a change in the dimensional stability of test specimens at temperatures T > TG (amorphous) or T > TS (semi-crystalline), which is caused by the resetting of molecular orientations and the relaxation of residual stresses. The orientations arise as a result of the processing (extrusion, injection moulding or deep drawing) and are therefore dependent on processing parameters. These parameters are the temperature of the mould and the melt, the injection and holding pressure, the flow path length and the cooling gradient of the backsheet film.

[0039] For example, the film has a shrinkage in MD according to DIN 55543-4 of more than 50 %, preferably of more than 60 %, in particular of more than 70 % and a shrinkage in MD of less than 95 %, preferably of less than 90 %, in particular less than 85 %.

[0040] In one embodiment of the invention, the shrinkage in CD according to DIN 55543-4 of more than 5 %, preferably of more than 10 %, in particular of more than 15 % and a shrinkage in MD of less than 40 %, preferably of less than 30 %, in particular less than 25 %. This makes it possible to shrink the film around the items to form a stable and transport-safe package.

[0041] Films and sheets with a thickness of up to 1 mm are tested using strip or shoulder specimens. According to ISO 527-3 and ASTM D 882, the usual specimen shape is the strip. This sample shape can be easily produced with a cutting press or a film cutter. Shoulder samples are often used in quality control. In this case, a direct-measuring extensometer is required with which the specimen strains can be recorded directly on the specimen. Typical test results such as the yield stress, the yield strain, the maximum stress and the nominal elongation at break are recorded.

[0042] The tensile properties are determined according to DIN EN ISO 527. In the tensile test, a test strip of Multipack shrink film is stretched at a constant speed specified in the test standard and the force F is recorded with the change in length ΔL of the measuring section L₀.

[0043] For example, the film has a tear strength in MD according to DIN EN ISO 527 of more than 300 mN, preferably more than 350 mN, in particular more than 400 mN.

[0044] In one embodiment of the invention, the tear strength in CD according to DIN EN ISO 527 of more than 2000 mN, preferably more than 2500 mN, in particular more than 3000 mN and less than 12000 mN, preferably less than than 10000 mN, in particular less than 8000 mN. Thus, the secure and stable design of the package made of the multipack shrink film can be ensured.

[0045] In one variant of the invention, the film has a secant modulus at 3 % elongation in MD according to DIN EN ISO 527 of more than 180 MPa, preferably of more than 200 MPa, in particular of more than 220 MPa.

[0046] For example, the film has a secant modulus at 3 % elongation in CD according to DIN EN ISO 527 of more than 190 MPa, preferably of more than 210 MPa, in particular of more than 230 MPa. In this way, the secure and stable design of the packaging can be ensured with the aid of the multipack shrink film.

[0047] For example, the film has an elongation at break in MD according to DIN EN ISO 527 of more than 200 %, preferably of more than 250 %, in particular of more than 300 % and in CD according to DIN EN ISO 527 of more than 300 %, preferably of more than 400 %, in particular of more than 500 %. Based on these physical characteristics, the multipack shrink film can be designed as a dimensionally stable package.

[0048] The Haze value is a measure of the haze or gloss of transparent films. The method for measuring the haze value is described in ASTM D 1003 and DIN EN ISO 2813. Preferably, the multipack shrink film has a gloss according to DIN EN ISO 2813 of less than 30 USI, preferably less than 25 USI, in particular less than 20 USI. As a result, the multipack shrink film has a particularly high-quality appearance.

[0049] In one variant of the invention, the multipack shrink film has a transparency of more than 65 USI, preferably of more than 75 USI, in particular of more than 85 USI according to DIN 53416, which makes the multipack shrink film particularly suitable for carrying out an imprint.

[0050] For example, the multipack shrink film has a gloss at 20 °C according to DIN EN ISO 2813 of more than 10 USI, preferably more than 20 USI, in particular more than 30 USI, which ensures a high-quality optical design of the packaging.

[0051] In order to realise the recyclability of the multipack shrink film and thus also the sorting in modern waste separation plants, such as for example the float-sink process, the density of the multipack shrink film is less than 0.99 g/cm³, preferably less than 0.97 g/cm³, in particular less than 0.94 g/cm³ and/or more than 0.80 g/cm³, preferably more than 0.90 g/cm³, in particular more than 0.92 g/cm³.

[0052] A particularly sustainable embodiment of the invention provides that the film comprises a proportion of recyclate of more than 40 % by weight, preferably more than 50 % by weight, in particular more than 60 % by weight. In this way, a sustainable and waste-avoiding product cycle can be realized.

[0053] For example, the film has a proportion of HDPE in a range from 2,5 % to 25 % by weight, preferably in a range from 7.5 % to 20 % by weight, in particular in a range from 10 % to 15 % by weight. The proportion of HDPE gives the multipack shrink film a favourable stiffness.

[0054] In one variant of the invention, the film has a proportion of LLDPE in a range from 10 % to 50 % by weight, preferably in a range from 15 % to 45 % by weight, more preferably in a range from 20 % to 40 % by weight.

[0055] In a variant of the invention, the film has a proportion of LDPE in a range from 10 % to 70 % by weight, preferably in a range from 20 % to 65 % by weight, in particular in a range from 30 % to 60 % by weight. The proportion of LLDPE gives the multipack shrink film a favourable toughness and shrinkage behaviour.

[0056] The multipack shrink film can, for example, be in the form of a monofilm.

[0057] In another variant of the invention, the multipack shrink film is designed as a multilayer film. In this case, the multipack shrink film can have three layers, five layers, seven layers or nine layers.

[0058] The thickness of the multipack shrink film was measured according to DIN 53370 and given as an average value. The multipack shrink film has a thickness in a range from 20 µm to 100 µm, preferably in a range from 25 µm to 90 µm, in particular in a range from 35 µm to 80 µm. This makes the multipack shrink film particularly material-saving and at the same time sufficiently stable.

[0059] According to the invention, the multipack shrink film is produced in a process in which a film is extruded in a monolayer or multilayer, then printed, for example in a flexographic printing process, and the openings are perforated into the multipack shrink film with the aid of a laser.

[0060] According to the invention, the film with an integrated label is used as a shrink film for a pack of items.

[0061] For example, a multipack shrink film with a label is used to avoid additional packaging waste that cannot be recycled by type.

[0062] The advantageous design of a multipack shrink film as a mono-material construction with an integrated label for removal for an economical as well as barrier-free payment process combines the recyclability of the pack with the elimination of additional work steps in the production of the multipack shrink film.

[0063] Further advantages and features of the invention can be seen from the description of an example of an embodiment on the basis of a drawing and from the drawing itself.

[0064] Thereby shows

Fig. 1 a top view of a multipack shrink film made up for a pack,

Fig. 2 is a top view of a packaged bundle of items with an integrated label.

[0065] Fig. 1 shows a top view of a prefabricated multipack shrink film 1. The multipack shrink film 1 has three prints 2, 3 and 4, whereby the prints 3 and 4 are arranged laterally and the print 2 is arranged on top of the packaging.

[0066] Next to the print 2, the integrated label 5 is arranged on the upper side of the pack. The label 5 consists of the same polymeric material as the multipack shrink film 1, in particular a mixture of polyethylenes and a recyclate of polyethylene. The label 5 has an outer edge 6 formed by spaced openings 7.

[0067] The openings 7 are arranged at a distance 12 from one another, the distance 12 in the embodiment shown being 3.5 mm. The openings 7 are circular and have a diameter of 2.5 mm. The openings 7 thus form a material weakening which ensures easy removal of the integrated label 5 from the multipack shrink film 1 by the engagement of, for example, a fingernail in the engagement opening 8.

[0068] The label 5 comprises a machine-readable barcode 9 which, after removal of the integrated label 5 from the multipack shrink film 1, can be handed to a supermarket checkout for an economic as well as barrier-free payment process.

[0069] Fig. 2 shows a top view of a pack 10 of items 11 with integrated label 5 packed with a multipack shrink film 1. The label 5 has an outer edge 6 formed by spaced-apart openings 7. The openings 7 form a weakening of the material. The integrated label 5 can be easily removed from the multipack shrink film 1 by inserting a fingernail, for example, into the opening 8, whereby the multipack shrink film 1 firmly and securely encloses the items 11 of the pack 10 for further transport as intended.

Claims

1. Multipack shrink film (1) for a pack (10) of items (11),

wherein the film (1) comprises at least substantially only one single plastic grade and a removable label (5) comprising a visual form (9),

characterized in that,

- the label (5) is made of the same polymeric material as the film (1),

- wherein the label (5) is integrated into the film (1),

- the label (5) having an outer edge (6) formed by spaced-apart openings (7), which form a perforation which limits the label (5) in the film (1),

- said openings (7) being spaced apart by a distance (12).

2. Multipack shrink film according to claim 1, characterized in that, the openings (7) have a diameter in a range of 0.1 mm to 0.5 mm.

3. Multipack shrink film according to claim 1 or 2, characterized in that, the openings (7) are spaced apart by a distance (12) from the center of one opening (7) to the center of the next opening (7) being in a range of 1.0 mm to 6.0 mm.

4. Multipack shrink film according to at least one of the proceeding claims, characterized in that, the label (5) is positioned on the upper side of the film (1) in between of items (11).

5. Multipack shrink film according to at least one of the proceeding claims, characterized in that, the openings (7) are arranged in a geometric figure around the machine readable form (9).

6. Multipack shrink film according to at least one of the proceeding claims, characterized in that, the outer edge (6) has an engagement hole (8) for removing the label (5) from the film (1), the engagement hole (8) having a long side with a range of 5 mm to 20 mm and having a short side with a range of 0.5 mm to 5 mm.

7. Multipack shrink film according to at least one of the proceeding claims, characterized in that, the openings (7) are rimmed with molten polymer material.

8. Multipack shrink film according to at least one of the proceeding claims, characterized in that, the film (1) has a content of LLDPE in a range from 10 % to 50 % by weight.

9. Multipack shrink film according to at least one of the proceeding claims, characterized in that, the film (1) has a content of LDPE in a range from 15 % to 70 % by weight.

10. Multipack shrink film according to at least one of the proceeding claims, characterized in that, the film (1) has a content of HDPE in a range from 2,5 % to 25 % by weight.

11. Multipack shrink film according to at least one of the proceeding claims, characterized in that, the film (1) has a shrinkage in MD according to DIN 55543-4 of more than 60 %, preferably of more than 70 %, in particular of more than 75 % and a shrinkage in MD of less than 95 %, preferably of less than 90 %, in particular less than 85 %.

12. Multipack shrink film according to at least one of the proceeding claims, characterized in that, the film (1) has a shrinkage in CD according to DIN 55543-4 of more than 5 %, preferably of more than 10 %, in particular of more than 15 %. and a shrinkage in CD of less than 40 %, preferably of less than 30 %, in particular less than 25 %.

13. Multipack shrink film according to at least one of the proceeding claims, characterized in that, the film (1) has a tear strength in MD according to DIN EN ISO 527 of more than 300 mN, preferably of more than 350 mN, in particular of more than 400 mN.

14. Multipack shrink film according to at least one of the proceeding claims, characterized in that, the film (1) has a tear strength in CD according to DIN EN ISO 527of more than 2000 mN, preferably of more than 2500 mN, in particular of more than 3000 mN and less than 12000 mN, preferably less than than 10000 mN, in particular less than 8000 mN.

15. Multipack shrink film according to at least one of the proceeding claims, characterized in that, the film (1) has an elongation at break in MD according to DIN EN ISO 527 of more than 200 %, preferably of more than 250 %, in particular of more than 300 %.

16. Multipack shrink film according to at least one of the proceeding claims, characterized in that, the film (1) has an elongation at break CD according to DIN EN ISO 527 of more than 300 %, preferably of more than 400 %, in particular of more than 500 %.

17. Multipack shrink film according to at least one of the proceeding claims, characterized in that, the removable label (5) comprising a visual, machine-readable form (9).

18. Method for producing a multipack shrink film (1)
characterized in that,
the openings (7) are perforated in the multipack shrink film (1) with the aid of a laser.

19. Use of a film (1) with an integrated label (5) as a shrink film for a pack (10) of items (11).

Drawing