Packaging material and method of providing packaging material

Abstract

The present invention relates to a packaging material and a method for providing a packaging material. A packaging material is provided, comprising a laminate having a core material layer (20) and having a plurality of defined areas (11a-g) for forming a face of a package (1) by means of crease lines. At least one defined area (11g) is provided with at least one pre-laminated hole (5) and at least one compression feature (30) of a non-crease line arranged adjacent to the pre-laminated hole (5). The at least one compression feature (30) comprises at least one straight line (30a-b, 30g-i), and the periphery of the pre-laminated hole (5) is circular.

Description

[0001] This application is a divisional application of the invention patent application with application number 201810126370.8, application date February 8, 2018, applicant is Tetra Laval Group and Finance Co., Ltd., and the invention name is "Packaging material and method for providing packaging material". Technical Field

[0002] The present invention relates to a packaging material, in particular to a packaging material having at least one pre-laminated hole. The present invention also relates to a method for providing such a packaging material, and a package formed from the packaging material. Background Art

[0003] It is generally known to use paperboard-based packaging materials to form product containers, such as containers for packaging and storing liquid foods.

[0004] In order to ensure the desired qualities of the final package, for example in terms of food safety and integrity, the packaging material may comprise different layers. For example, the packaging material may comprise a paper or paperboard core layer, wherein at least one polymer composition or layer is applied on one side of the paper or paperboard core layer to constitute the outer surface of the final package, and a polymer composition or layer is applied on the opposite side or inside. The polymer composition on the inside may in some cases be provided with a protective film (such as aluminum); the polymer composition therefore generally also comprises an outer layer in contact with the product to be contained in the final package. Typically, an additional polymer composition is applied to the protective film to avoid direct contact between the food contained in the package and the protective layer itself, thereby preventing the food from wetting the aluminum and other layers in the laminate.

[0005] The product container formed by the above packaging material can be provided with a pre-laminated hole, for example, to facilitate the use of a straw inserted into the package through the pre-laminated hole when in use. At the hole, the core layer is missing, so that only the outer polymer layer and the inner polymer layer, which may optionally include a protective film sandwiched therebetween, cover the hole.

[0006] In the process of manufacturing this packaging material, the core layer is processed by punching holes in it and then laminated in one or more steps. This process is often called "converting".

[0007] The forming and filling of individual product containers or packages is performed using a filling machine that typically includes a plurality of successive processing stations. For example, the filling machine may have a feed station for receiving a web of packaging material, a sterilizing station for sterilizing the web of packaging material, a tube forming station at which the web is continuously formed into a tube by sealing the side edges of the web of packaging material, a filling station for filling the tube with product, a sealing station for providing a transverse seal to the tube and for cutting the sealed package from the upstream tube, and a final folding station for forming the package into its final shape.

[0008] Another example of a filling machine uses pre-made blanks to form individual packages.

[0009] The pre-laminated holes are usually arranged in the upper part of the final package, in the area extending between one edge of the upper end and the upper transverse seal. Since the pre-laminated holes cause a local weakening of the packaging material, there is a risk that the upper part of the package will wrinkle undesirably in the vicinity of the pre-laminated holes. Any wrinkling that would occur during the sealing and / or final shaping of the package means that there are limited possibilities for adjusting or fine-tuning the operation of these filling machine stations during production, especially due to the very high production speeds of the filling machines. Summary of the invention

[0010] It is an object of the present invention to at least partially overcome one or more of the above limitations of the prior art. In particular, it is an object to reduce the formation of wrinkles around a pre-laminated hole in a packaging material during sealing and / or forming of the package.

[0011] One aspect of the invention is a packaging material comprising a laminate having a core material layer and having a plurality of defined areas for forming a face of a package by means of crease lines. At least one defined area is provided with at least one pre-laminated hole and at least one compression feature of a non-crease line arranged adjacent to the pre-laminated hole. The at least one compression feature comprises at least one straight line and the perimeter of the pre-laminated hole is circular.

[0012] The defined area may be used to form the upper end of the package.Preferably, the pre-laminated hole is used to form the straw hole of the package, whereby the straw hole is located in an area that is easily accessible to a customer.

[0013] The at least one compression feature may be arranged within 10 mm, for example within 0-6 mm, of the pre-laminated hole.Testing has shown that such a distance between the pre-laminated hole and the compression feature significantly reduces the formation of wrinkles in the final package.

[0014] The at least one compression feature is formed by embossing, debossing or compression.

[0015] Referring to the at least one straight line mentioned above, it may be two straight lines extending on opposite sides of the pre-laminated hole.

[0016] The at least one compression feature may include at least one line extending from a perimeter of the pre-laminated aperture and radially away from the pre-laminated aperture.

[0017] According to a second aspect, a package is provided, comprising the packaging material according to the first aspect, wherein the packaging material is closed by a seal to form a closed package.

[0018] According to a third aspect, there is provided a method for providing a packaging material, the method comprising: providing a core material layer having at least one hole, laminating the core material layer to form a laminated packaging material having a pre-laminated hole, providing the packaging material with a series of crease lines for defining folding lines used during package forming and sealing, and providing at least one compression feature of a non-crease line adjacent to the pre-laminated hole before or after the core material layer is provided with at least one hole. The at least one compression feature comprises at least one straight line, and the perimeter of the pre-laminated hole is circular.

[0019] Specifically, some aspects of the present invention can be described as follows:

[0020] 1. A packaging material comprising a laminate having a core material layer (20) and having a plurality of defined areas (11a-g) for forming a face of a package (1), wherein at least one defined area (11g) is provided with at least one pre-laminated hole (5) and at least one compression feature (30) arranged adjacent to the pre-laminated hole (5), wherein the at least one feature (30) comprises at least one line (30a-f, 30j) extending along at least a portion of the periphery of the pre-laminated hole (5).

[0021] 2. The packaging material according to clause 1, wherein the defined area (11g) is used to form an upper end (3) of the package (1).

[0022] 3. Packaging material according to clause 1 or 2, wherein the pre-laminated hole (5) is used to form a straw hole of the package (1).

[0023] 4. Packaging material according to any of the preceding clauses, wherein the at least one compression feature (30) is arranged within 10 mm, such as within 0-6 mm, of the pre-laminated hole (5).

[0024] 5. The packaging material according to any of the preceding clauses, wherein the at least one compressed feature (30) is formed by embossing, debossing or compression.

[0025] 6. Packaging material according to clause 5, wherein the at least one line (30a-b) is straight.

[0026] 7. Packaging material according to clause 6, comprising two straight lines (30a-b) extending on opposite sides of the pre-laminated hole (5).

[0027] 8. Packaging material according to clause 5, wherein said at least one line (30c-f, 30j) is curved.

[0028] 9. Packaging material according to clause 8, comprising two curved lines (30c-d) extending on opposite sides of the pre-laminated hole (5).

[0029] 10. Packaging material according to clause 8 or 9, wherein each curved line (30c-d, 30f) extends between 30° and 150° of the circumference of the pre-laminated hole (50).

[0030] 11. Packaging material according to clause 8 or 9, wherein the curved line (30e, 30j) forms a circular line extending along the entire periphery of the pre-laminated hole (50).

[0031] 12. A packaging material according to any one of clauses 1 to 5, wherein the at least one feature (30) comprises at least one line (30g-i) extending from the periphery of the pre-laminated hole (5) and radially away from the pre-laminated hole (5).

[0032] 13. A package (1) comprising a packaging material (10) according to any of the preceding clauses, wherein the packaging material (10) is closed by a seal (12, 14) to form a closed package (1).

[0033] 14. A method for providing a packaging material (10), comprising:

[0034] - providing a core material layer (20) having at least one hole,

[0035] - laminating said core material layers (20) to form a laminated packaging material (10) having pre-laminated holes (5), and

[0036] - before or after the core material layer (20) is provided with at least one hole, providing at least one compression feature (30) adjacent to the pre-laminated hole (5), wherein the at least one compression feature (30) comprises at least one line (30a-f, 30j) extending along at least a portion of the periphery of the pre-laminated hole (5).

[0037] Other objectives, features, aspects and advantages of the technical solution of the present invention will be shown according to the following detailed description and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Embodiments of the invention will now be described by way of example with reference to the accompanying schematic drawings.

[0039] Figure 1is an isometric view of the package;

[0040] Figure 2 is a cross-sectional view of the packaging material,

[0041] Figure 3 This is a top view of the upper end of the package.

[0042] Figure 4 is a top view of the upper end of a package according to one embodiment,

[0043] Figure 5a is a cross-sectional view of the upper end of a package according to an embodiment,

[0044] Figure 5b is a cross-sectional view of the upper end of a package according to one embodiment,

[0045] Figure 6a -f is a top view of the upper end of a package according to various embodiments, and

[0046] 7a-c are schematic diagrams of methods for providing packaging material according to various embodiments. DETAILED DESCRIPTION

[0047] Reference Figure 1 , showing an example of package 1. Package 1 represents a package called Tetra Commercially available liquid food packaging. Figure 1 As can be seen in the figure, the package 1 comprises a relatively flat upper end 3 provided with a straw hole 5. The straw hole 5 is formed by a pre-laminated hole of the packaging material 10 used to produce the package 1 as will be explained later.

[0048] The upper end 3 represents one of a plurality of defined areas 11a-f of the packaging material 10. Each defined area 11a-f will be used to form a face of a package 1 made from the packaging material 10. It should be understood that not all defined areas 11a-f are in the Figure 1 , and each region 11a - f may be delimited from adjacent regions 11a - f, for example, by crease lines.

[0049] The package 1 is formed from a web of packaging material 10 which is formed into a tube by sealing the longitudinal edges of the packaging material 10 to each other. The longitudinal seal 12 is formed at Figure 1 It can be seen extending along the upper end 3 in FIG, but it is obvious that the longitudinal seal 12 extends along the entire package 1. When the tube is filled with its intended contents, the package 1 is sealed and cut from the tube by providing a top and bottom transverse seal. Figure 1In the embodiment, only the top transverse seal 14 is shown. For final shaping, the two upper flaps 16a, 16b are folded and connected to the body 18 of the package 1. Although not shown, the final shape of the bottom end is achieved in a similar manner, although the flaps are folded inwards. The final shaping of the package 1 is preferably made by using crease lines.

[0050] exist Figure 2 , the packaging material 10 for producing the package 1 is shown in more detail. A cross section along Figure 1 The line AA in the figure is intercepted.

[0051] The packaging material 10 comprises a core material layer 20, an outer layer 22 and an inner layer 24, wherein the outer layer 22 and the inner layer 24 are applied to opposite sides of the core material layer 20 after at least one hole has been cut. Thus, the core material layer 20 is provided with holes before conversion, i.e. before performing one or more lamination processes to produce the final packaging material 10. Preferably the holes are punched, the holes may be formed in a sequential pattern on the core layer web or individually on individual blanks.

[0052] The outer layer 22 applied to one side of the core material layer 20 is suitable for providing the outer surface of the package 1 to be produced, which outer surface and the outer layer 22 face the surrounding environment of the package. The inner layer 24 is applied to the other side of the core material layer 20 and is suitable for providing the inner surface of the package 1 to be produced, which inner surface is in contact with the product contained in the package 1.

[0053] The core material layer 20 may be a sheet material for providing rigidity to the packaging material 10, and may preferably be made of a material such as paperboard or cardboard.

[0054] The outer layer 22 may comprise at least one layer of polymer material which is applied during a lamination process to the core material layer 20. Furthermore, one of the layers constituting the outer layer 22 may be a decorative layer constituting the outer surface of the package 1 to be formed.

[0055] A printed layer may be included on the core material layer 20 , adjacent to the outer layer 22 .

[0056] The inner layer 24 may include at least one layer of a polymer material. Figure 2 As shown, the first and inner layer 24a is arranged to face the product to be packaged by the package 1. A protective layer 24b may be present between the core material layer 20 and the inner layer 24a. The protective layer 24b may be a foil, such as a metal foil, preferably an aluminum foil. The protective layer 24b blocks oxygen and light to maintain the nutritional value and flavor of the food in the package 1 at ambient temperature.

[0057] In addition, a laminate layer 24c may be present between the protective layer 24b and the core material layer 20. The laminate layer 24c may be at least one polymer material layer.

[0058] According to one embodiment, the inner layer 24 of the packaging material 10 intended for the inside of the finished package 1 in contact with the product contained in the package 1 comprises, starting from the core material layer 20, a laminating layer 24c, a protective layer 24b and a sealing layer 24a. The laminating layer 24c enables the core material 20 to adhere to any applied protective layer 24b. The sealing layer 24a enables the package to be sealed.

[0059] The polymer layers 22, 24a, 24c of the packaging material 10 may be any suitable type of polymer material, preferably a plastic material such as polyethylene.

[0060] Now go to Figure 3 , the upper end 3 of the package 1 is shown in further detail. It should be noted that Figure 3 The upper end 3 of the packaging material 1 is intended to mean any part of the packaging material 10 provided with a pre-laminated hole 5, so that the following description also applies to Figure 1 Other types of packaging than the one shown in 1. Such packaging may include, for example, Tetra Parallelepiped packages such as Tetra Such gable top packaging, etc.

[0061] The pre-laminated hole 5 is typically arranged somewhere between one lateral end of the upper end 3 and a transverse seal 14 which may be centrally located across the upper end 3 .

[0062] exist Figure 3 During the sealing and / or forming process of the upper end 3 shown, as described above, wrinkles W may appear in the packaging material 10. Tests have shown that when wrinkles appear, they exist in a region A extending from the edge of the pre-laminated hole 5 toward the transverse seal 14. In particular, region A extends approximately ±60° from the dashed line X, which represents the shortest distance between the pre-laminated hole and the transverse seal 14, as shown in FIG. Figure 3 This means that substantially no wrinkles are observed outside of region A. It is further observed that the wrinkle problem becomes more significant as the diameter of the pre-laminated holes 5 increases.

[0063] exist Figure 4 The inventors have surprisingly found that by providing one or more features 30 adjacent to the pre-laminated holes 5, compressive forces in the packaging material 10 occurring during sealing and / or forming of the final package 1 will be absorbed to a greater extent, thereby preventing the formation of wrinkles in the packaging material 10.

[0064] like Figure 4As can be seen in the figure, this feature 30 can be obtained by providing two symmetry lines 30a, 30b in the packaging material on each side of the pre-laminated hole 5. Each line 30a, 30b is realized by modifying the core material layer 20, for example, by embossing, debossing and / or compressing, and each line 30a, 30b preferably extends at least along the entire diameter D1 of the pre-laminated hole 5 in the direction towards the transverse seal 14. However, in some embodiments, the length of each line 30a, 30b30b may be less than the diameter D1 of the pre-laminated hole 5.

[0065] In particular, the lines 30a, 30b do not intersect the transverse seal 14, but are spaced a distance from the transverse seal 14. Advantageously, the lines 30a, 30b are provided before laminating the packaging material 10, and by providing a distance between the end of each line 30a, 30b and the area of ​​the transverse seal 14, the packaging material 10 is smooth and uniform at the transverse seal 14, thereby improving the integrity of the seal 14.

[0066] The thickness D2 of each line 30a, 30b may be in the range of 0.5-2 mm, or slightly larger than this range. In addition, the shortest distance D3 between the pre-laminated hole 5 and the line 30a, 30b should preferably be greater than 1.5 mm, such as 3 mm. The diameter D1 of the pre-laminated hole may generally be in the range of 4-10 mm.

[0067] The method of providing feature 30 can be performed in different ways, such as Figure 5a and 5b As shown. Figure 5a As shown, the core material layer 20 may be processed so that its otherwise flat shape is changed into a relief pattern corresponding to the shape of the lines 30a, 30b. This may be achieved by embossing or debossing, depending on the final design of the package 1. For embossing, the outer protrusions (e.g. Figure 5a ), while the embossing provides a recessed pattern on the outside of the packaging material 10.

[0068] exist Figure 5b In the embodiment of the present invention, the features 30 are formed by compressing the core material layer 20, however a flat anvil is used to prevent the pattern from protruding on the outside.

[0069] In any of the above examples, the core material layer 20 will be compressed to some extent in the area of ​​the feature(s) 30. Figure 5b For example, the entire feature will be a compression pattern. Figure 5a The feature 30 will form a deflection from an initially flat shape on both sides of the core material layer, but compression of the core material layer will in fact exist because the shape of the outside will not correspond to the shape of the inside.

[0070] Typically, the packaging material 10 is provided with a series of crease lines for defining fold lines used during forming and sealing of the package 1. Advantageously, the features 30 may therefore be provided during the same crease process, thus eliminating the need for a separate processing step.

[0071] Other examples of features 30 that have been shown to reduce wrinkling problems in the area around the pre-laminated holes 5 are shown in Figure 6a -f. Each feature 30 discussed below will provide compression in the core material layer and may be formed as an indentation on the inside or outside (i.e., a pure compression feature), an indentation on the inside and a boss on the outside (i.e., an embossed feature), or a boss on the inside and an indentation on the outside (i.e., an embossed feature). The thickness of each feature 30 is substantially similar to the thickness D2, which is 0.5

[0072] In the range of 2mm or slightly higher.

[0073] from Figure 6a Initially, the packaging material 10 is provided with two features 30 near the pre-laminated hole 5. Each feature 30 is formed as a curve 30c, 30d that surrounds and traces a portion of the periphery of the pre-laminated hole. The curvature of each line 30c-d is preferably designed so that the distance between the line 30c-d and the periphery of the pre-laminated hole 5 is constant. Each line 30c-d can extend in the range of 30-150 °, and the lines 30c-d are preferably separated from each other at both ends.

[0074] Another example is shown in Figure 6b. Here only one feature 30 forms a circular line 30e around the pre-laminated hole 5. The radial distance between the feature 30e and the pre-laminated hole 5 is preferably chosen so that the circular line 30e does not intersect the transverse seal 14.

[0075] In Fig. 6c, the feature 30 is provided as a semicircular or curved line 30f arranged in the area between the pre-laminated hole 5 and the transverse seal 14. The line 30f may extend in the range of 30-150°, preferably symmetrically around the line X.

[0076] exist Figure 6d , in which the feature 30 is formed as a straight line 30g extending from the pre-laminated hole 5 towards the transverse seal 14. Preferably, the line 30g coincides with the vertical line X. As mentioned above, the line 30g should be spaced a small distance from the transverse seal 14.

[0077] Figure 6eAnother example is shown. Here the features 30 are arranged as two spaced apart lines 30h-i, which extend at an angle to each other. The lines 30h-i are arranged symmetrically with respect to the imaginary line X, and they may be arranged to cover an angular distance of approximately ±60° with respect to the imaginary line X. Figure 6d 30 g , lines 30 h - i are interrupted so that they do not intersect the transverse seal 14 .

[0078] exist Figure 6f In FIG. 6B , the feature 30 is formed as a circular line 30j around the pre-laminated hole 5. Compared with the feature 30e shown in FIG. 6b , the circular line 30j is arranged close to the pre-laminated hole. The circular line 30j is associated with many advantages. For example, by using a punching device, perfect centering of the line 30j can be ensured to form the feature 30. In addition, since the thickness of the core material layer 20 will be reduced, in particular in the case of forming the feature 30j by compression, the lamination of the packaging material on the punched hole will be easier.

[0079] Turning now to Figures 7a-c, a method 100 will be described, whereby the method 100 is performed to provide a packaging material 10 as described above. According to Figure 7a, the method 100 is performed by a first step 102, wherein the core material layer 20 is provided with at least one hole. In a subsequent step 104, the core material layer 20 is laminated to form a laminated packaging material 10 having a pre-laminated hole 5. The method 100 also includes a step 106, wherein at least one compression feature 30 is arranged adjacent to the pre-laminated hole 5.

[0080] As shown in Figure 7b, the compression features 30 may be provided prior to lamination of the core material layer 20.

[0081] In an even more preferred method 100 shown in FIG. 7 c , the step 106 of providing compression features is performed before the step 102 of providing at least one hole and the step 104 of laminating the layer 20 of core material.

[0082] From the above description, although several embodiments of the invention have been described and shown, the invention is not restricted thereto but may also be implemented in other ways within the scope of the subject matter defined in the appended claims.

Claims

1. A packaging material comprising a laminate having a core material layer (20) and having a plurality of delimited areas (11a-g) for forming a face of a package (1) by means of crease lines, wherein at least one delimited area (11g) is provided with at least one pre-laminated hole (5), characterised in that The at least one defined area (11g) is provided with at least one compressed feature (30) of a non-crease line arranged adjacent to the pre-laminated hole (5), wherein the at least one compressed feature (30) comprises at least one straight line and the perimeter of the pre-laminated hole (5) is circular.

2. The packaging material according to claim 1, wherein The defined area (11g) is used to form the upper end (3) of the package (1).

3. The packaging material according to claim 1 or 2, wherein the pre-laminated hole (5) is used to form a straw hole of the package (1).

4. The packaging material according to claim 1 or 2, wherein: The at least one compression feature (30) is arranged within 10 mm of the pre-laminated hole (5).

5. The packaging material according to claim 4, wherein The at least one compression feature (30) is arranged within 0-6 mm of the pre-laminated hole (5).

6. The packaging material according to claim 1 or 2, wherein: The at least one compressed feature (30) is formed by embossing, debossing or compression.

7. The packaging material according to the preceding claim 1 or 2, wherein said at least one straight line comprises two straight lines (30a-b) extending on opposite sides of said pre-laminated hole (5).

8. The packaging material according to claim 1 or 2, characterized in that: The at least one straight line extends from the periphery of the pre-laminated hole (5) and radially away from the pre-laminated hole (5).

9. A package (1) comprising a packaging material (10) according to any one of the preceding claims, wherein the packaging material (10) is closed by a seal (12, 14) to form a closed package (1).

10. A method for providing a packaging material (10), comprising: - providing a core material layer (20) having at least one hole, - laminating said core material layers (20) to form a laminated packaging material (10) having pre-laminated holes (5), - providing the packaging material with a series of crease lines for defining folding lines used during forming and sealing of the package, and - before or after the core material layer (20) is provided with at least one hole, at least one compression feature (30) of a non-crease line adjacent to the pre-laminated hole (5) is provided, wherein the at least one compression feature (30) comprises at least one straight line (30a-b, 30g-i) and the periphery of the pre-laminated hole (5) is circular.

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