EP4701947A1 - A blank and a package - Google Patents

Abstract

The disclosure relates to a package (2), and to a blank (1) configured to be folded into a package (2), the blank (1) comprising: a paperboard blank (100) and a plastic sheet (200) configured to form at least part of an inside surface of the package (2), wherein the paperboard blank (100) comprises: a bottom panel (110) and three or more side wall panels (120a-d) each having a respective height extension (H1) and a respective length extension (L1), wherein the plastic sheet (200) is attached to two adjacent corner-forming side wall panels (120a-d) at a respective upper attachment zone (150a-d) and forms a corner sheet portion (210a-d) extending between and interconnecting the two adjacent side wall panels (120a-d) as seen in a flat-laid state of the blank (1), and wherein the corner sheet portion (210a-d) is configured to be double folded on to itself and into an interior of the package (2) when the two side wall panels (120a-d) are folded relative to the bottom panel (110) to form the two side walls.

Description

A BLANK AND A PACKAGE

Field of invention

The invention relates to a blank configured to be folded into a package. The invention also relates to a package.

Technical Background

When designing a package from a blank, it is often desirous to take into account a number of different design criteria. The package should, e.g., be designed such that it makes efficient use of material, is easy to prepare for use, is space efficient during transport and storage, and provides a strong structure during use. Moreover, it is often desirable that the package should be formed in a manner that requires a limited number of folding operations, and/or folding operations which are easy to perform. When formed, the package should be capable of maintaining its structure when being filled with its intended content. In cases where the intended content of the package is to some extent in liquid form, another design criterion is often added, namely that the package should be leak-proof during normal use.

Furthermore, when designing a package, which is intended to be disposed of after use, it is preferred to use a material with low environmental impact, such as paperboard, and also use a minimum of such material. It is also desirable to consider the design of the package such that it is easy for the user to recycle the package correctly after use. It is a common problem that package materials cannot be recycled since they do not consist of a mono-material or that the process steps for the end user to correctly recycle the package are too troublesome, leading to the package being recycled incorrectly or not recycled at all.

In WO 07091004 there is disclosed a container which is formed by folding a blank. The resulting container is sealed against spillage of liquid contents. This sealing is accomplished by the blank being formed of a paper board blank being coated with a plastic material and by designing the corner portions of the blank with a plurality of triangular corner panels that are folded in an overlapping manner such that tight comers are formed. However, the use of a paperboard coated with a plastic material makes the foldable container difficult to recycle.

Another example of a liquid tight package is disclosed in EP 3936449. The package is formed of a paperboard blank having a bottom panel and four side wall panels. At the respective corner of the bottom panel, the paperboard blank is also provided a triangular corner panel. The side of the blank intended to be in contact with the food products is coated or laminated with a plastic layer or film. The paperboard blank and the plastic film laminated thereto is at the respective corner portion designed such that each corner element consists of 2 V-shaped segments where one of them consists of a cardboard layer and a laminated layer and the other consists only of a laminated layer. When the blank is folded into a package, the V-shaped paperboard corner portion is folded into the interior of the package such that the plastic film laminated thereto extends on one side of the V-shaped paper board corner portion and the other V-shaped segment of laminated layer ends up on the opposing side of the V-shaped corner portion such that the inwardly extending paperboard flap is covered on both sides by a plastic lamination layer. However, also this design with a paperboard blank and a thereto laminated plastic material is difficult to recycle.

Thus, there is still a need for a package adequately addressing at least some of the design criteria mentioned above.

Summary of invention

It is an object of the invention to provide a package addressing at least some of the design criteria that the package should make efficient use of material, be easy to prepare for use, be leak proof, be easy to recycle, and provide a strong structure during use.

This object has been achieved by a blank configured to be folded into a package, the blank comprising: a paperboard blank and a plastic sheet, the plastic sheet being configured to form at least part of an inside surface of the package, wherein the paperboard blank comprises: a bottom panel configured to form a bottom of the package, and three or more side wall panels configured to form side walls of the package, wherein the side wall panels each has a respective height extension and a respective length extension, wherein the length extension is orthogonal to said respective height extension and wherein the side wall panels are configured to be folded such that the height extension extends upwardly from the bottom, wherein two of said three or more side wall panels, which are configured to form two adjacent side walls and together define an upwardly extending side wall corner, are foldably connected to a respective one of two edges of the bottom panel forming a corner of said bottom panel, wherein the plastic sheet is attached to the two side wall panels at a respective attachment zone extending along an intended upper portion of the respective one of the two side wall panels, wherein the plastic sheet forms a corner sheet portion extending between and interconnecting the two adjacent side wall panels as seen in a flat-laid state of the blank, and wherein the corner sheet portion is configured to be double folded on to itself and into an interior of the package when the two side wall panels are folded relative to the bottom panel to form the two side walls.

It may be noted that the plastic sheet may be configured to form the complete inside surface of the package, i.e. , to completely cover all those parts of the paperboard blank that face inwardly. However, the plastic sheet may also be configured to only partially form part of the inside surface of the package. That is, a design where some parts of the paperboard blank that face inwardly are covered by the plastic sheet and some parts of the paperboard blank that face inwardly are not covered by the plastic sheet. The parts of the inside surface covered by the plastic sheet may e.g., be a corner. However, in the preferred embodiments, the plastic sheet forms the complete inside surface, at least the complete inside surface beneath a certain height of the package. Thus, in the preferred embodiment, the plastic sheet is a continuous plastic sheet which fully covers the bottom panel, and the side wall panels at least up to the respective attachment zone as well as forming said corner sheet portions. That is, in the preferred embodiment, the plastic sheet is configured to form a closed bottom portion of the package, where the closed bottom portion extends up to said attachment zones. Closed bottom refers in this case to a continuous plastic sheet providing the barrier properties of the plastic sheet to the bottom of the package at least up to said attachment zones.

It may be noted that upwardly does not necessarily refer to vertical. Even though it is preferred that the sides extend vertically upwardly, the side walls may be inclined such that they are inclined outwardly or inwardly relative to vertical. Preferably, the angle of inclination is less than +-15° relative to vertical.

It may in this context be noted that a corner of the bottom panel is basically a point formed by two side edges of the bottom panel meeting each other, whereas a side wall corner refers to a line extending upwardly. The line may be curved but is typically a straight line and it typically extends upwardly in a vertical direction or slightly inclined relative to vertical.

Further, it is to be understood that the plastic sheet may be continuously or intermittently attached along the respective attachment zone.

It may be noted that the intended upper portion refers to a portion which will be an upper portion when the respective side wall panel has been folded to form the respective side wall.

It may in this context be noted that the corner sheet portion which is configured to be double folded on to itself and into an interior of the package may further be folded towards and preferably also be attached to an inside surface of a portion of the plastic sheet covering a side wall panel. Thus, it may be said that the double-folded corner sheet portion may be tucked away alongside an inside surface of a sidewall. The attachment of said corner sheet portion may be desirous to prevent that the packed items get stuck to the corner sheet portion and tamper with the leak proof properties. However, it is to be understood that the corner sheet portion need not be attached to provide a leak proof package.

One advantage of the invention is that the blank is easily folded into a package, both manually and automatically, since the number of required folds is low and there are no troublesome alignment activities involved.

Another advantage is that the blank is formed from two materials that are easy to separate after use which allows for easy recycling. The two materials may be recycled in different fractions, such as paper recycling and plastic recycling, respectively. One or both of the materials may, but need not, from a recycling perspective be a mono-material, i.e. , a material formed solely of constituents accepted for a specific kind of recycling, which will give a greater recyclability. Thus, it is made possible to have a paper board blank solely formed of paper material and recycled as paper material and a plastic film solely formed of plastic material which is separated from the paper board blank and recycled as plastic material. However, it may be noted that the paper board blank may be coated with plastic material on the inside and/or the outside, but since the blank is provided with a plastic film configured to form an inside of the package, any such coating may be kept thin and thereby have only a marginal negative impact on the recyclability of the paper board blank. Thus, the design of the blank may increase the likelihood of the package actually being recycled by the end user as well as being recycled correctly, which contributes to a more sustainable package.

Preferably, the plastic sheet fully covers at least the corner and a bottom corner portion surrounding the corner of the bottom panel, as well as fully covers at least side wall panel portions along those edges of the two side wall panels that define said side wall corner, said side wall panel portions extending along the height extension from the bottom panel to respective attachment zone. As has been discussed above, the inventive concept may be used to provide a closed corner. In such a design, the closed corner is provided by the plastic sheet covering the side wall corner, the corner of the bottom panel and the bottom corner portion. In other words, the plastic sheet covers all openings present between the bottom panel and the side wall panels when they are folded relative to each other. However, as also discussed above, the inventive concept is preferably used to provide a fully closed bottom portion of the package, at least up to the attachment zones. In such an instance, the plastic sheet is a continuous sheet covering the bottom panel and the side wall panels at least to a height extension corresponding to the respective attachment zone and forming a respective corner sheet portion between all side wall panels being adjacent each other and being configured to form a respective side wall corner.

The corner sheet portion preferably extends at least substantially along a geometrical line from attachment zone to attachment zone on the respective side wall panel. Extends at least substantially along is intended to refer to that the corner sheet portion preferably has a size and shape such that its outer edge, the edge being farthest from the corner of the bottom panel, is at such a distance from the corner of the bottom panels that it is at least not substantially smaller than the distance between the corner and a geometrical straight line extending between the two attachment zones. Preferably, the distance between the corner and the free edge is at least 75% of the distance between the corner and the geometrical straight line. Thereby, the corner sheet portions may form a sufficient height at the side wall corners when the package is formed. In the preferred embodiment, the free edge extends basically along the geometrical line with the distance from the corner to the free edge being within 90% and 110% of the distance between the corner and the geometrical line.

The respective attachment zone preferably extends along at least 80%, more preferably along at least 90% of the length extension of the respective one of the two side wall panels. It may in this context be noted that if the plastic sheet is intermittently attached to the side wall panels along the attachment zone, the attachment zone as seen along the length extension, refers to the distance between the two most distant attachment points as seen along the length extension. Thus, the attachment zone extending along at least 80% and preferably along at least 90% of the length extension does not necessarily refer to the total extension of the actual attachments. The total extension of the actual attachments may be less than said at least 80% or preferably at least 90% as long as the distance between the two most distant attachment points defines an attachment zone as discussed above.

Moreover, it is preferred that the attachment zone extends along the length extension such that there is less than 2cm, preferably less than 1cm distance between the edge of the side wall panel and the outermost point of the attachment zone as seen along the length extension.

If the attachment zone is formed of intermittent attachment points, it is preferred that the actual attachments make up at least 40% of the extension of the attachment zone as seen along the length extension.

Preferably, the respective attachment zone has a height extension less than 15mm, preferably less than 10 mm, along the height extension of the respective one of the two side wall panels. As discussed above, the attachment zone extends along an intended upper portion of the respective one of the two side wall panels. Preferably, the intended upper portion corresponds to the upper most 30% of the side wall panels as seen in a state where the blank has been folded into a package.

Each side wall panel is preferably foldably connected to a respective edge of the bottom panel. It may be noted that since each side wall panel may be folded in relation to the bottom panel, each side wall may be considered to form one of the adjacent side walls together with each of the two side walls being located on a respective side of the first mentioned side wall, whereby all the side walls form adjacent side walls, and each define a respective upwardly extending side wall corner on the two sides thereof. Further, it may be noted that it is preferred that all side walls are configured to be interconnected with its respective adjacent side wall panel by a respective corner sheet portion of the plastic sheet, at least up to the respective attachment zone.

The plastic sheet may further be attached to the bottom panel of the blank, preferably at least in a vicinity of said corner of the bottom panel. In a vicinity may e.g., refer to a distance being less than 3cm, preferably less than 1 cm, from the corner of the bottom panel. It may be noted that the plastic sheet may be attached to the bottom panel at any position, e.g., along a central line of the bottom panel or along one or several respective edges of the bottom panel. By having the plastic sheet attached to the bottom panel may be desirous especially when the blank is to be folded manually since such attachment will help keeping the plastic sheet in the intended position during the folding operation.

The paperboard blank preferably comprises four side wall panels, and wherein the bottom panel is rectangular. Such a paperboard blank is easy to fold and the resulting package with a rectangular bottom shape is typically space efficient when several such package are transported and/or stored side by side.

At least two side walls are preferably each provided with two locking flaps being foldably connected along a respective one of two opposing sides of the respective side wall panel, wherein the respective locking flap extends between said respective side of said respective side wall and a free end of said respective locking flap. The respective locking flaps are configured to be folded in a direction towards an adjacent side wall and, by means of e.g., an adhesive, such as glue, tape with one or two adhesive sides, staples, or other kinds of connectors, be attached to an outer surface of said adjacent side wall. Alternatively, or as a complement thereto, the locking flaps may be attached to the adjacent side wall by mechanical interaction such as by inserting the respective locking flap or a tab thereof into a mechanical lock formed by a recess or slot present in the respective adjacent side wall panel. A mechanical lock may be advantageous to have when the blank is to be folded manually. The respective locking flaps are configured to hold the adjacent side wall panels in its intended wall forming position. It is to be understood that the locking flaps may be attached to an inner surface of the adjacent side wall, such that the locking flap is inserted between the inner surface of the adjacent side wall and the plastic sheet covering said adjacent side wall. However, it is an advantage of having the locking flap attached to the outer surface of the adjacent side wall since this makes the assembly of the package easier than having it attached on said inner surface. The locking flaps may have a length extension extending from a fold line of the respective side wall and the respective locking flap towards a free end of said respective locking flap. The length extension may be at least 10-15 mm, preferably 15- 20 mm, more preferably 20-50mm. The locking flaps may have a height extension being orthogonal to the length extension of the locking flap. The height extension of the locking flap may correspond to the respective height extension of the respective side wall panel. Irrespective of if the height extension of the locking flap corresponds to the respective height extension of the respective side wall panel, or not, the height extension of the locking flap is preferably at least 10-30 mm, more preferably 30-50 mm, and most preferably 50-60 mm.

At least two side wall panels may each comprise a respective top wall panel being foldably connected to the respective side wall panel along a side of the respective side wall panel being opposite the bottom panel. The top wall panel may be configured to be folded such that the top wall panel is substantially parallel to the bottom panel of the blank. The top wall panel and side wall panel preferably has an equal extension as seen along the direction of the fold line. In the other direction, the top wall panel may have a width extension extending between a free end of the top wall panel and a fold line of the top wall panel and the respective side wall panel. The width extension of the respective top wall panel may have an extension corresponding to 50%, preferably 30%, more preferably 10 % of the extension of the bottom panel in a direction parallel to the extension of the top wall panel. The top wall panels may have a width extension corresponding to the extension of the bottom panel such that the respective top wall panels of the at least two side wall panels abut each other end to end or such that they are folded on top of each other. By having one or both of the top wall panels corresponding to 100% of the extension of the bottom panel or by having two or more top wall panels having a combined width extension corresponding to 100% or more of the extension of the bottom panel, the top wall panel is configured to form a closed top wall of the package. For some intended usages of the package, it may be desirous to have a top wall panel that forms a closed top wall. For other intended usages it is desirous to have a top of the package being partly open. Such an open top may in turn be closed by a lid or covered by a wrapping, such as a plastic film wrapping.

Moreover, it may be noted that the top wall panel may be covered by the plastic sheet. In such an instance, the plastic sheet may be attached to the top wall panel at an attachment portion. The plastic sheet may completely or partially cover the extension of the top wall panel.

The aforementioned top wall panels may each comprise two locking flaps being foldably connected to a respective one of two opposing sides of the respective top wall panel, the two locking flaps being configured to be attached to two opposing side wall panels wherein each such opposing side wall panel is a neighbouring side wall panel to the respective side wall panel being provided with the top wall panel. The extension of the respective locking flaps of the top wall panels in a direction away from the top wall panel may be 10-20 mm, preferably 20-40 mm, and more preferably 40-60 mm. In the direction across the fold line between the top wall panel and the side wall panel, the locking flaps may have an extension equal to the extension of the top wall panel. However, it may be noted that, alternatively, the locking flaps may in this direction have an extension being different from the extension of the top wall panel, especially if the top wall panel has a large extension or small extension. In any case the extension of the respective locking flaps of the top wall panels may also in this direction be 10-20 mm, preferably 20-40 mm, and more preferably 40-60 mm. The respective locking flaps are configured to be folded in a direction towards an outer surface of the opposing side wall panels and be attached to said outer surface of the opposing side walls by means of e.g., glue, tape, or cardboard connectors. The respective locking flaps are configured to hold the side wall panels in its intended wall forming position.

The thickness of the plastic sheet is preferably 30-90 pm, and more preferably 60-90 pm. A plastic sheet of such a thickness is typically sufficiently flexible to be easily folded, but still strong enough to allow the plastic sheet to easily be peeled off from the paperboard blank. The paperboard blank may further comprise one or more corner blank portions formed in an area defined by two adjacent side wall panels, the respective corner blank portion being configured to be folded outwardly to an exterior of the package when the two side wall panels are folded relative to the bottom panel to form the two side walls. The area defined by two adjacent side wall panels refers to an area formed by a joint imaginary extension of two adjacent side wall panels meeting in a corner. The size of the corner blank portion may correspond to the size of the corner sheet portion. It is to be understood that the corner sheet portion may cover said corner blank portion at least up to the attachment zones. Further, it is to be understood that the corner sheet portion is not attached to the corner blank portion. This may also be referred to as that the corner sheet portion is separate from and freely movable relative to the corner blank portion. Any limitation in their relative moveability is solely due to the fact that both the corner blank portion and corner sheet portion may be connected respectively attached to the side wall panels. Moreover, after the corner blank portion is folded outwardly to an exterior of the package, the corner blank portion may be folded towards an outside surface of an adjacent side wall panel and attached to said adjacent side wall panel. The corner blank portion may be attached to any one of the adjacent side wall panels.

The above mentioned object is also achieved by a package formed of a blank comprising: a paperboard blank and a plastic sheet, wherein the paperboard blank comprises: a bottom panel forming a bottom of the package, and three or more side wall panels forming side walls of the package, wherein the side wall panels each has a respective height extension extending upwardly from the bottom, and a respective length extension, wherein the length extension is orthogonal to said respective height extension, wherein two of said three or more side wall panels which forms two adjacent side walls and which together define an upwardly extending side wall corner are foldably connected to a respective one of two edges of the bottom panel forming a corner of said bottom panel, wherein the plastic sheet forms at least part of an inside surface of the package and is attached to the two side wall panels at a respective attachment zone extending along an upper portion of the respective one of the two side wall panels, wherein the plastic sheet forms a corner sheet portion extending between and interconnecting the two adjacent side wall panels as seen in a flat-laid state of the blank, and wherein the corner sheet portion is double folded on to itself and into an interior of the package when the two side wall panels are folded relative to the bottom panel to form the two side walls.

It may be noted that the use of first, second, third, fourth, fifth, etc. are mainly to be seen as labels facilitating reading and that it does not necessarily mean that there need to be all the intervening numbers of items, such as portions or panels, present. It may e.g., be noted that it is contemplated to have a design where there is a first portion, a second portion, a third portion and a fifth portion, with the fourth portion being omitted. However, to facilitate reading, we have consistently used the numbering first, second, third, fourth, etc., as labels, and in a sense based on an embodiment including all conceivable portions.

It may also be noted that panel names such as top, floor and side wall are intended meant to be read as labels, not necessarily defining the orientation of the panel. As an example, the package does not need to be oriented such that the first top panel actually forms the top of the package. The package may be oriented such that the panel labelled first top panel actually forms a side wall or even forms a bottom of the package, does not have to be located over the floor panel, but could be positioned under, on the side of, or in any other way relative to it. However, in the preferred embodiment, the package will be oriented so that the floor panel faces downward, the top panels face upward, and the side wall panels faces outwards from an axis between top and floor. Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to "a/an/the [element, device, component, means, step, etc]" are to be interpreted openly as referring to at least one instance of said element, device, component, means, step, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated.

The invention may also in short be said to relate to a package, and to a blank configured to be folded into a package, the blank comprising: a paperboard blank and a plastic sheet configured to form at least part of an inside surface of the package, wherein the paperboard blank comprises: a bottom panel and three or more side wall panels each having a respective height extension (H1 ) and a respective length extension, wherein the plastic sheet is attached to two adjacent corner-forming side wall panels at a respective upper attachment zone and forms a corner sheet portion extending between and interconnecting the two adjacent side wall panels as seen in a flat-laid state of the blank, and wherein the corner sheet is configured to be double folded on to itself and into an interior of the package when the two side wall panels are folded relative to the bottom panel to form the two side walls.

Brief of the

The invention will by way of example be described in more detail with reference to the appended schematic drawings, which show a presently preferred embodiments of the invention.

Figure 1 discloses a paperboard blank configured to form a package.

Figure 2 discloses a blank formed of the paperboard blank shown in figure 1 and a plastic sheet attached thereto.

Figure 3 discloses the blank shown in figure 2 when said blank is folded such that a corner sheet portion of the plastic sheet is double folded on to itself and into an interior of the package.

Figure 4 discloses a package formed by the blank shown in figure 2. Figure 5 discloses a second embodiment of a blank formed of a paperboard blank and a plastic sheet as a variation to the embodiment shown in figure 2.

Detailed of preferred embodiments

With reference to Figs. 1-5, there is disclosed a blank 1 comprising a paperboard blank 100 and a plastic sheet 200. The paperboard blank 100 and the plastic sheet 200 are configured to be brought together and folded to form a package 2. The plastic sheet 200 is configured to form at least part of an inside surface of the package 2. Preferably, the plastic sheet 200 forms a continuous inside surface covering the whole inside of the package 2. The plastic sheet 200 is attached to the paperboard blank 100 at a respective attachment zone 150a-d, preferably by heat sealing or gluing.

With reference to Fig. 1 , the paperboard blank 100 is shown in a flat- laid state. The paperboard blank 100 comprises a rectangular bottom panel 110 configured to form a bottom of the package 2. It may in this context be noted that the bottom panel 110 may have any shape.

The paperboard blank 100 as shown in Fig.1 , further comprises four side wall panels 120a-d configured to form side walls of the package 2. The side wall panels 120a-d each has a respective height extension H1 and a respective length extension L1 , wherein the length extension L1 is orthogonal to said respective height extension H1 . The side wall panels 120a-d are configured to be folded such that the height extension H1 extends upwardly from the bottom. The side wall panels 120a-d are configured to form adjacent side walls and together define four upwardly extending side wall comers 121a-d. The side wall panels 120a-d are foldably connected to a respective edge 111a-d of the bottom panel 110 forming a corner 112a-d of said bottom panel 110. It may be noted that the side wall panels 120a-d may be fewer, or more than four, and preferably the number of side wall panels 120a-d correspond to the number of edges 111a-d of the bottom panel 110. In the preferred embodiment, each side wall panel 120a-d is to be folded in relation to the bottom panel 110. In the preferred embodiment, each side wall is considered to form one of the adjacent side walls together with each of the two side walls being located on a respective side of the first mentioned side wall, whereby all the side walls form adjacent side walls, and each define a respective upwardly extending side wall corner 121a-d on the two sides thereof. It may be noted that upwardly does not necessarily refer to vertical. Even though it is preferred that the sides extend vertically upwardly, as shown in Fig.4, the side walls may be inclined such that they are inclined outwardly or inwardly relative to vertical. Preferably, the angle of inclination is less than +-15° relative to vertical. As shown in Fig. 3, a corner 112a-d of the bottom panel 110 is basically a point formed by two side edges 111 a-d of the bottom panel 110 meeting each other, whereas a side wall corner 121 a-d refers to a line extending upwardly, vertically or with a slight inclination resulting from said possible inclination of the side walls. The line may be curved but is typically a straight line and it typically extends upwardly in a vertical direction or slightly inclined relative to vertical.

Moreover, as shown in Fig.1 , in the first preferred embodiment, all side wall panels 120a-d each comprise a respective top wall panel 130a-d being foldably connected to the respective side wall panel 120a-d along a side of the respective side wall panel 120a-d being opposite the bottom panel 110. It is to be noted that it is not necessary that all side wall panels comprise a respective top wall panel. The top wall panel 130a-d is in this preferred embodiment configured to be folded such that the top wall panel 130a-d is substantially parallel to the bottom panel 110 of the blank 1 , as shown in Fig.4. The top wall panel 130a-d and side wall panel 120a-d preferably has at their mutual fold line an equal extension as seen along the direction of their mutual fold line. In the other direction, the top wall panel 130a-d has a width extension extending between a free end of the top wall panel 130a-d and a fold line of the top wall panel 130a-d and the respective side wall panel 120a- d. As shown in Figs.1-4, in the preferred embodiment, two opposing top wall panels 130a-d have a width extension W1 being greater than a width extension W2 of two other opposing top wall panels 130a-d. Further, in the preferred embodiment, the top wall panels 130a-d, as shown in Fig.4, does not form a closed top wall of the package 2.

The width extension W1 , W2 of the respective top wall panel 130a-d may have different extensions depending upon the specific design and intended use of the package. The package may e.g., be designed to be an open top package with the top panels 130a-d being intended to primarily provide strength and stack ability to the package, and in such case it is considered appropriate that the top panels 130a-d each has an extension corresponding to up to about 30% and at least about 10 % of the extension of the bottom panel 110 in a direction parallel to the width extension W1 , W2 of the top wall panel 130a-d. The top wall panels 130a-d may alternatively have a width extension W1 , W2 corresponding to the extension of the bottom panel 110 such that the respective top wall panels 130a-d of the side wall panels 120a-d abut each other end to end or such that they are folded on top of each other. By having one or more of the top wall panels 130a-d corresponding to 100% of the extension of the bottom panel 110 or by having two or more top wall panels 130a-d having a combined width extension W1 , W2 corresponding to 100% or more of the extension of the bottom panel 110, the top wall panels 130a-d are configured to form a closed top wall of the package 2. Such a set of top wall panels 130a-d may e.g., be provided with a tear-away portion in one or more of the top wall panels 130a-d. For some intended usages of the package 2 it may be desirous to have a top wall panel 130a-d that forms a closed top wall. For other intended usages, it is desirous to have a top of the package 2 being partly open. Such an open top may in turn be closed by a lid or covered by a wrapping, such as a plastic film wrapping.

As shown in Figs. 1-2, in the preferred embodiment two opposing top wall panels 130a-d each comprises two locking flaps 131a-d being foldably connected to a respective one of two opposing sides of the respective top wall panel. The two locking flaps 131a-d are configured to be attached to two opposing side wall panels 120a-d, as shown in Fig. 4, wherein each such opposing side wall panel 120a-d is a neighbouring side wall panel 120a-d to the respective side wall panel 120a-d being provided with the top wall panel 130a-d. The extension of the respective locking flaps 131a-d of the top wall panels 130a-d in a direction away from the top wall panel 130a-d is preferably at least about 10-20 mm, more preferably at least about 20-40 mm, and most preferably at least about 40-60 mm, to provide a strong attachment. In the direction across the fold line between the top wall panel 130a-d and the side wall panel 120a-d, the locking flaps 131a-d have preferably an extension equal to the extension of the top wall panel 130a-d. However, it may be noted that, alternatively, the locking flaps 131a-d may in this direction have an extension being different from the extension of the top wall panel 130a-d, especially if the top wall panel 130a-d has a large extension or small extension. In any case, the extension of the respective locking flaps 131a-d of the top wall panels 130a-d may also in this direction preferably be at least about 10-20 mm, more preferably at least about 20-40 mm, and most preferably at least about 40-60 mm.

With reference to Fig.2 the plastic sheet 200 is attached to the paperboard blank 1 shown in Fig.1. Preferably, the plastic sheet 200 forms the complete inside surface, at least the complete inside surface beneath a certain height of the package 2. In such a case, the plastic sheet 200 is a continuous sheet covering the bottom panel 110 and the side wall panels 120a-d at least to a height extension H2 corresponding to the respective attachment zone 150a-d, and forms a respective corner sheet portion 210a-d between all side wall panels 120a-d that are adjacent each other and configured to form a respective side wall corner 121a-d. As shown in Fig.2, the plastic sheet 200 is configured to form a closed bottom portion of the package 2, where the closed bottom portion extends up to said attachment zones 150a-d. Closed bottom refers in this case to a continuous plastic sheet 200 providing the barrier properties of the plastic sheet 200 to the bottom of the package 2 at least up to said attachment zones 150a-d. However, the plastic sheet 200 may also be configured to partially form part of the inside surface of the package 2. That is, a design where some parts of the paperboard blank 100 that face inwardly are covered by the plastic sheet 200 and some parts of the paperboard blank 100 that face inwardly are not covered by the plastic sheet 200. In such an instance, the plastic sheet 200 preferably fully covers at least the corner 112a-d and a bottom corner portion 113a-d surrounding the corner 112a-d of the bottom panel 110, as well as fully covers at least side wall panel portions 123a-d along those edges of the two side wall panels 120a-d that define the side wall corner 121a-d, said side wall panel portions 123a-d extending along the height extension H2 from the bottom panel 110 to respective attachment zone 150a-d. It may be noted that if one or more of the side walls are configured to extend with an inclination relative to vertical, the edge at the side wall panel portion 123a-d of the neighbouring side wall panel 120a-d is typically angled relative to its respective height extension such that the edges of the respective side wall portion 123a-d still meet along an inclined upwardly extending corner line. As has been discussed above, the inventive concept may be used to provide a closed corner. In such a design, the closed corner is provided by the plastic sheet 200 covering the side wall corner 121 a-d, the corner 112a-d of the bottom panel 110 and the bottom corner portion. In other words, the plastic sheet 200 covers all openings present between the bottom panel 110 and the side wall panels 120a-d when they are folded relative to each other. However, as also discussed above, the inventive concept is preferably used to provide a fully closed bottom portion of the package 2, at least up to the attachment zones 150a-d.

Moreover, it may be noted that the top wall panel 130a-d may be covered by the plastic sheet 200, not shown in any of the figures. In such an instance, the plastic sheet 200 may be attached to the top wall panel 130a-d at an attachment portion. The plastic sheet 200 may completely or partially cover the extension of the top wall panel 130a-d.

Further, the thickness of the plastic sheet 200 is preferably 30-90 pm, and more preferably 60-90 pm.

As shown in Fig.2, the plastic sheet 200 is preferably continuously attached to the side wall panels 120a-d at a respective attachment zone 150a-d extending along an intended upper portion 122a-d of the respective side wall panel 120a-d. The respective attachment zone 150a-d preferably extends along at least 80%, more preferably along at least 90% of the length extension L1 of the respective one of the two side wall panels 120a-d. Moreover, it is preferred that the attachment zone 150a-d extends along the length extension L1 such that there is less than 2cm, preferably less than 1cm distance between the edge of the side wall panel 120a-d and the outermost point of the attachment zone 150a-d as seen along the length extension L1 . Preferably, the respective attachment zone 150a-d has a height extension H3 less than 15mm, more preferably less than 10 mm, along the height extension H1 of the respective side wall panel 120a-d. However, it is to be understood that the plastic sheet 200 may, according to an alternative not shown in the figures, be only intermittently attached along the respective attachment zone 150a-d,. It may in this context be noted that if the plastic sheet 200 is intermittently attached to the side wall panels 120a-d along the attachment zone 150a-d, the attachment zone 150a-d as seen along the length extension L1 , refers to the distance between the two most distant attachment points as seen along the length extension L1. Thus, the attachment zone 150a-d extending along at least 80% and preferably along at least 90% of the length extension L1 does not necessarily refer to the total extension of the actual attachments. The total extension of the actual attachments may be less than said at least 80% or preferably at least 90% as long as the distance between the two most distant attachment points defines an attachment zone 150a-d as discussed above. If the attachment zone 150a-d is formed of intermittent attachment points, it is preferred that the actual attachments make up at least 40% of the extension of the attachment zone 150a-d as seen along the length extension L1 .

As shown in Fig.2, and as discussed above, the attachment zone 150a-d extends along an intended upper portion 122a-d of the respective one of the two side wall panels 120a-d. Preferably, the intended upper portion 122a-d corresponds to the upper most 30% of the side wall panels 120a-d as seen in a state where the blank 1 has been folded into a package 2. Moreover, the plastic sheet 200 may further be attached to the bottom panel 110 of the paperboard blank 100, preferably at least in a vicinity of said corner 112a-d of the bottom panel 110. In a vicinity may e.g., refer to a distance being less than 3cm, preferably less than 1cm, from the corner 112a-d of the bottom panel 110. It may be noted that the plastic sheet 200 may be attached to the bottom panel 110 at any position, e.g., along a central line of the bottom panel 110 or along one or several respective edges 111 a-d of the bottom panel 110. Attachment of the plastic sheet 200 to the bottom panel 110 is especially useful in case the blank 1 is intended to be folded manually into a package 2.

With reference to Fig. 3, in the preferred embodiment, two side wall panels 120a-d are folded in relation to the bottom panel 110 to form two adjacent side wall panels 120a-d and the corner sheet portion 210a-d extending between the adjacent side wall panels is double folded on to itself and into an interior of the package 2. As shown in Fig.2, the plastic sheet 200 forms a corner sheet portion 210a-d extending between and interconnecting the two adjacent side wall panels 120a-d as seen in a flat-laid state of the blank 1 . When the two side wall panels 120a-d are folded relative to the bottom panel 110 to form the two adjacent side walls, the corner sheet portion 210a-d is configured to be double folded on to itself and into an interior of the package 2, which is shown in Fig.3. The corner sheet portion 210a-d extends at least substantially along a geometrical line GL from attachment zone 150a- d to attachment zone 150a-d on the respective side wall panel 130a-d. Extends at least substantially along is intended to refer to that the corner sheet portion 210a-d preferably has a size and shape such that its outer edge, the edge being farthest from the corner 112a-d of the bottom panel 110, is at such a distance from the corner 112a-d of the bottom panel 110 that it is at least not substantially smaller than the distance between the corner 112a-d and a geometrical straight line extending between the two attachment zones 150a-d, as seen in Fig. 3. Preferably, the distance between the corner 112a-d and the free edge is at least 75% of the distance between the corner 112a-d and the geometrical straight line. Thereby, the corner sheet portions 210a-d is considered to form a sufficient height at the side wall comers 121a- d when the package 2 is formed. In the preferred embodiment, the free edge extends basically along the with the distance from the corner 112a-d to the free edge being within 90% and 110% of the distance between the corner 112a-d and the geometrical line.

In Fig. 3 only two opposing corner sheet portions 210a-b are visible, but it may be noted that it is preferred that all side walls of the package 2 are configured to be interconnected with its respective adjacent side wall panel 120a-d by a respective corner sheet portion 210a-d of the plastic sheet 200, at least up to the respective attachment zone 150a-d. Further, it may be noted that the corner sheet portion 210a-d, which is configured to be double folded on to itself and into an interior of the package 2, may further be folded towards and preferably also be attached to an inside surface of a portion of the plastic sheet 200 covering a side wall panel 120a-d. Thus, it may be said that the double-folded corner sheet portion 210a-d may be tucked away alongside an inside surface of a side wall.

With reference to Fig.4, the blank 1 of a first preferred embodiment is shown in its folded state, thus forming the package 2. The respective top wall panels 130a-d have been folded such that two opposing top wall panels 130a-d extend over two other opposing top wall panels 130a-d. The respective locking flaps 131a-d of the top wall panel 130a-d have been folded in a direction towards an outer surface of the opposing side wall panels 120a- d and attached to said outer surface of the opposing side walls by means of e.g., glue, tape, or cardboard connectors. The respective locking flaps 131a-d are configured to hold the top wall panels 130a-d and the side wall panels 120a-d in its intended wall forming position. As shown in Fig.4, the locking flaps 131a-d are present at the top wall panels 130a-d of the short side of the package 2. However, it is to be understood that, in another possible embodiment, not shown in any of the figures, the two opposing top wall panels 130a-d on the long side of the package 2 may be arranged with locking flaps 131 a-d. In such an instance, the top wall panels 130a-d of the long side of the package 2 would preferably be folded such that they extend over the top wall panels 130a-d of the short side of the package 2. The package 2 according to the design shown in Fig.4, allow the package 2 to be filled with its intended content before or after the top wall panels 130a-d being folded to their final position in which they are substantially parallel to the bottom of the package 2. If the top wall panels 130a-d are configured to form a closed top wall of the package 2, the package 2 must be filled with its intended content before the top wall panels 130a-d are folded towards the bottom of the package 2 and attached to each other or attached to the respective side wall panels 120a-d.

With reference to Fig.5, another embodiment of the blank 1 is shown. Unless a difference is expressly stated, the above discussion concerning different variants and preferred embodiments of the blank 1 discussed above with reference to Figs. 1-4 are equally applicable to the blank 1 discussed below with reference to Fig. 5. The blank 1 has at least two side walls each provided with two locking flaps 132a-d being foldably connected along a respective one of two opposing sides of the respective side wall panel 120a- d. The respective locking flap 132a-d extends between said respective side of said respective side wall and a free end of said respective locking flap 132a- d. It may be noted that the respective locking flap 132a-d is foldably connected to one of the side walls 120a-d at the respective corner and is separated, or at least separable, from the other side wall 120a-d by a cut-line or the like. The respective locking flap 132a-d is configured to be folded in a direction towards an adjacent side wall and, by means of e.g., an adhesive, such as glue, tape with one or two adhesive sides, staples, or other kinds of connectors, be attached to an outer surface of said adjacent side wall. Alternatively, or as a complement thereto, the locking flaps 131a-d may be attached to the adjacent side wall by mechanical interaction such as by inserting the respective locking flap 132a-d or a tab thereof into a mechanical lock formed by a recess or slot present in the respective adjacent side wall panel. The respective locking flaps 132a-d are configured to hold the adjacent side wall panels 120a-d in its intended wall forming position. Further, it is to be understood that the locking flaps 132a-d may be attached to an inner surface of the adjacent side wall, such that the locking flap 132a-d is inserted between the inner surface of the adjacent side wall and the plastic sheet 200 covering said adjacent side wall. However, it may be noted that the corner sheet portions 210a-d are still configured to be double-folded onto itself with the locking flap 132a-d inserted between the double-folded corner sheet portion 210a-d and the adjacent side wall panel.

The locking flaps 132a-d, shown in Fig.5, have a length extension L2 extending from a fold line of the respective side wall and the respective locking flap 132a-d towards a free end of said respective locking flap 132a-d. The length L2 extension may be at least 10-15 mm, preferably at least 15-20 mm, more preferably at least 20-50mm. The locking flaps 132a-d have a height extension H4 being orthogonal to the length extension L2 of the locking flap 132a-d. As shown in Fig.5, the height extension H4 of the locking flap 132a-d corresponds to the respective height extension H1 of the respective side wall panel 120a-d. However, the locking flap may have another height extension H4. Irrespective of if the height extension H4 of the locking flap 132a-d corresponds to the respective height extension H1 of the respective side wall panel 120a-d, or not, the locking flap 132a-d is preferably at least 10-30 mm, more preferably at least 30-50 mm, and most preferably at least 50-60 mm. It should be noted that the plastic sheet 200 is not attached to the locking flaps 131 a-d.

In another embodiment, not shown in any of the figures, the paperboard blank 100 may further comprise one or more corner blank portions formed in an area defined by two adjacent side wall panels 120a-d. The respective corner blank portion is e.g., formed of two triangular portions defined by two outer fold lines, with a respective such outer fold line being formed between a respective side wall panel and the corner blank portion, and by an inner fold line extending from the corner of the bottom panel 110 and bisecting the corner blank portion. The respective corner blank portion is configured to be folded outwardly to an exterior of the package 2 when the two side wall panels 120a-d are folded relative to the bottom panel 110 to form the two side walls. The respective corner blank portion will occupy the same area as the locking flap 132a-d shown in Fig.5, but in this instance be foldably connected to both adjacent side walls 120a-d. The area defined by two adjacent side wall panels 120a-d refers to an area formed by a joint imaginary extension of two adjacent side wall panels 120a-d meeting in a corner. The size of the corner blank portion may correspond to the size of the locking flaps 131 a-d or to the size of the corner sheet portion 21 Oa-d. It is to be understood that the corner sheet portion 21 Oa-d may cover said corner blank portion at least up to the attachment zones 150a-d. Further, it should be noted that the corner sheet portion 21 Oa-d is not attached to the corner blank portion. This may also be referred to as that the corner sheet portion 21 Oa-d is separate from and freely movable relative to the corner blank portion. Any limitation in their relative moveability is solely due to the fact that both the corner blank portion 140a-d and corner sheet portion 21 Oa-d may be connected respectively attached to the side wall panels 120a-d. Moreover, after the corner blank portion is folded outwardly to an exterior of the package 2, the corner blank portion may be folded towards an outside surface of an adjacent side wall panel 120a-d and attached to said adjacent side wall panel 120a-d. The corner blank portion may be attached to any one of the adjacent side wall panels 120a-d.

Even though it is preferred that the blank is designed in accordance with the disclosure in the detailed disclosure of preferred embodiments and the appended drawings, it should be noted that a specific preferred embodiment of a specific component does not necessarily have to be combined with a specific embodiment of another component. Thus, advantages associated with a specific embodiment, including one or more features, of a specific component may be accomplished even though the other component(s) is/are designed in accordance with the more general disclosure under the summary of the invention rather than being defined in accordance with the specific embodiment disclosed in the detailed description.

Additionally, variations to the disclosed embodiments can be understood and effected by the skilled person in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage.

Claims

1. Blank (1) configured to be folded into a package (2), the blank (1 ) comprising: a paperboard blank (100) and a plastic sheet (200), the plastic sheet (200) being configured to form at least part of an inside surface of the package (2), wherein the paperboard blank (100) comprises: a bottom panel (110) configured to form a bottom of the package (2), and three or more side wall panels (120a-d) configured to form side walls of the package (2), wherein the side wall panels (120a-d) each has a respective height extension (H1 ) and a respective length extension (L1 ), wherein the length extension (L1 ) is orthogonal to said respective height extension (H1) and wherein the side wall panels (120a-d) are configured to be folded such that the height extension (H1) extends upwardly from the bottom, wherein two of said three or more side wall panels (120a-d), which are configured to form two adjacent side walls (120a-d) and together define an upwardly extending side wall corner (121 a-d), are foldably connected to a respective one of two edges (111 a-d) of the bottom panel (110) forming a corner (112a-d) of said bottom panel (110), wherein the plastic sheet (200) is attached to the two side wall panels (120a-d) at a respective attachment zone (150a-d) extending along an intended upper portion (122a-d) of the respective one of the two side wall panels (120a-d), wherein the plastic sheet (200) forms a corner sheet portion (210a-d) extending between and interconnecting the two adjacent side wall panels (120a-d) as seen in a flat-laid state of the blank (1 ), and wherein the corner sheet portion (210a-d) is configured to be double folded on to itself and into an interior of the package (2) when the two side wall panels (120a-d) are folded relative to the bottom panel (110) to form the two side walls.

2. Blank (1) according to claim 1 , wherein the plastic sheet (200) fully covers at least the corner (112a-d) and a bottom corner portion (113a-d) surrounding the corner (112a-d) of the bottom panel (110), as well as fully covers at least side wall panel portions (123a-d) along those edges of the two side wall panels (120a-d) that define said side wall corner (121a-d), said side wall panel portions (123a-d) extending along the height extension (H1 ) from the bottom panel (110) to respective attachment zone (150a-d).

3. Blank (1) according to claim 1 or 2, wherein the plastic sheet (200) is a continuous sheet covering the bottom panel (110) and the side wall panels (120a-b) at least to a height extension (H2) corresponding to the respective attachment zone (150a-d), and forming a respective corner sheet portion (210a-d) between all side wall panels (120a-d) being adjacent each other and being configured to form a respective side wall corner (121a-d).

4. Blank (1) according to any one of claims 1-3, wherein the corner sheet portion (210a-d) extends at least substantially along a geometrical line (GL) from attachment zone (150a-d) to attachment zone (150a-d) on the respective side wall panel (120a-d).

5. Blank (1) according to any one of claims 1-4, wherein the respective attachment zone (150a-d) extends along at least 80%, preferably along at least 90% of the length extension (L1 ) of the respective one of the two side wall panels (120a-d).

6. Blank (1) according to any one of claims 1-5, wherein the respective attachment zone (150a-d) having a height extension (H3) less than 15mm, preferably less than 10 mm, along the height extension (H1 ) of the respective one of the two side wall panels (120a-d).

7. Blank (1) according to any one of claims 1-6, wherein the intended upper portion (122a-d) corresponds to the upper most 30% of the side wall panels (120a-d) as seen in a state where the blank (1 ) has been folded into a package (2).

8. Blank (1) according to any one of claims 1-7, wherein each side wall panel (120a-d) is foldably connected to a respective edge (111 a-d) of the bottom panel (110).

9. Blank (1) according to any one of claims 1-8, wherein the plastic sheet (200) further is attached to the bottom panel (110) of the blank (1 ), preferably at least in a vicinity of said corner (112a-d) of the bottom panel (110).

10. Blank (1 ) according to any one of the claims 1-9, wherein the paperboard blank (100) comprises four side wall panels (120a-d), and wherein the bottom panel (110) is rectangular.

11 . Blank (1 ) according to any one of the claims 1 -10, wherein at least two side walls (120a-d) are each provided with two locking flaps (131 a-d) being foldably connected along a respective one of two opposing sides of the respective side wall panel (120a-d), wherein the respective locking flap (131a- d) extends between said respective side of said respective side wall (120a-d) and a free end of said respective locking flap (131 a-d).

12. Blank (1 ) according to any one of the claims 1-11 , wherein at least two side wall panels (120a-d) each comprises a respective top wall panel (130a-d) being foldably connected to the respective side wall panel (120a-d) along a side of the respective side wall panel (120a-d) being opposite the bottom panel (110).

13. Blank (1 ) according to claim 12, wherein said top wall panels (130a-d) each comprises two locking flaps (131a-d) being foldably connected to a respective one of two opposing sides of the respective top wall panel (130a-d), the two locking flaps (131a-d) being configured to be attached to two opposing side wall panels (120a-d) wherein each such opposing side wall panel (120a-d) is a neighbouring side wall panel (120a-d) to the respective side wall panel (120a-d) being provided with the top wall panel (130a-d).

14. Blank (1 ) according to any one of the claims 1-13, wherein the thickness of the plastic sheet (200) is preferably 30-90 pm, more preferably 60-90 pm.

15. Blank (1 ) according to any one of the claims 1-14, wherein the paperboard blank (100) further comprises one or more corner blank portions (140a-d) formed in an area defined by two adjacent side wall panels (120a-d), the respective corner blank portion (140a-d) being configured to be folded outwardly to an exterior of the package (2) when the two side wall panels (120a-d) are folded relative to the bottom panel (110) to form the two side walls.

16. Package (2) formed of a blank (1 ) comprising: a paperboard blank (100) and a plastic sheet (200), wherein the paperboard blank (100) comprises: a bottom panel (110) forming a bottom of the package (2), and three or more side wall panels (120a-d) forming side walls of the package (2), wherein the side wall panels (120a-d) each has a respective height extension (H1 ) extending upwardly from the bottom, and a respective length extension (L1 ), wherein the length extension (L1 ) is orthogonal to said respective height extension (H 1 ), wherein two of said three or more side wall panels (120a-d) which forms two adjacent side walls (120a-d) and which together define an upwardly extending side wall corner (121 a-d) are foldably connected to a respective one of two edges (111 a-d) of the bottom panel (110) forming a corner (112a-d) of said bottom panel (110), wherein the plastic sheet (200) forms at least part of an inside surface of the package (2) and is attached to the two side wall panels (120a-d) at a respective attachment zone (150a-d) extending along an upper portion (122a- d) of the respective one of the two side wall panels (120a-d), wherein the plastic sheet (200) forms a corner sheet portion (210a-d) extending between and interconnecting the two adjacent side wall panels (120a-d) as seen in a flat-laid state of the blank (1 ), and wherein the corner sheet portion (210a-d) is double folded on to itself and into an interior of the package (2) when the two side wall panels (120a-d) are folded relative to the bottom panel (110) to form the two side walls.