Patent Application
20170297799
Described herein are an opening device, a method of manufacturing an opening device and a packaging container for liquid or semi-liquid food, said packaging container having an opening device.
Packaging containers of the single use disposable type for liquid foods are often produced from a packaging material based on paperboard or carton. One such commonly occurring packaging container is marketed under the trademark Tetra Fino® Aseptic and is principally employed for aseptic packaging of liquid foods such as milk, fruit juices etc, marketed and sold for long term ambient storage. The packaging material in this known packaging container is typically a laminate comprising a bulk layer of paper or paperboard and outer, liquid-tight layers of thermoplastics. In order to render the packaging container gas-tight, in particular oxygen gas-tight, for example for the purpose of aseptic packaging such as packaging of milk or fruit juice, the laminate in these packaging containers normally comprises at least one additional such gas barrier layer, most commonly an aluminium foil.
On the inside of the laminate, i.e. the side intended to face the filled food contents of a container produced from the laminate, there is an innermost layer, applied onto the aluminium foil, which innermost, inside layer may be composed of one or several part layers, comprising heat-sealable adhesive polymers and/or heat-sealable polyolefins. Also on the outside of the paper or paperboard bulk layer, there is an outermost heat-sealable polymer layer (decor layer). The heat-sealable polymer layers are often based on low density polyethylene or blends thereof.
The packaging containers are generally produced by means of modern, high-speed packaging machines of the type that continuously form, fill and seal packages from a web or from prefabricated blanks of packaging material, e.g. Tetra Fino® Aseptic-type packaging machines. Packaging containers may thus be produced by the so-called form-fill-seal technology basically including continuous reforming a web of the laminated packaging material by means of a filling machine which forms, fills and seals the web into packages. More specifically, a continuous tube is formed from the web-fed packaging material; the web of packaging material is sterilized by applying a chemical sterilizing agent, such as a hydrogen peroxide solution, which, once sterilization is completed, is removed from the surfaces of the packaging material, e.g. evaporated by heating; and the web of packaging material so sterilized is maintained in a closed, sterile environment, and is formed into a vertical tube by sealing the longitudinal edges of the tube in an overlapping seal. The tube is filled with the food product, and is sealed and subsequently cut along equally spaced transverse sealing zones to form cushion-shaped or pillow-shaped packing containers.
An aspect of the Tetra Fino®-type packaging method is, as stated above, the possibility of continuous high-speed packaging, which has considerable impact on cost efficiency. Typically many thousands of packages may be prepared per hour. For example the Tetra Pak® A1 may manufacture about 10 000 packaging containers per hour (packaging containers of 0.5 litres or more), and about 15 000 packaging containers per hour (portion packages)
The Tetra Fino® Aseptic packaging containers are, as mentioned above, cushion-shaped or pillow shaped and commonly such packaging containers have an opening device that is generally provided in the form of a straw hole, or simply as a cut indicator, which is facilitated by a rather thin and thus tearable packaging material being used. Using conventional opening devices such as for example those comprising screw caps or pull-tabs would in most cases be fully functional. However, the type of packaging container is a high-volume (in terms of packaging containers per time unit) and low-cost packaging container (due to the properties of the packaging material), and such opening devices might hamper the production speed and be detrimental for the cost of the packaging container.
For this reason there is a need for an opening device having a high efficiency in regard of the amount of material used and the time needed for production of each opening device. It should be emphasized that even if the present invention was developed to solve a specific problem, the outcome may be applied to packages in a general sense and it should not be limited to a particular type of packages in this respect.
At least the above described need is solved by the present invention.
According to a first aspect the invention comprises an opening device on a packaging container for liquid or semi-liquid food. Said packaging container has a fold line and an opening line. The fold line and opening line intersect in an intersection point, said intersection point dividing the opening line into a first opening line portion and a second opening line portion. The opening device comprises a first opening device portion and a second opening device portion. The first opening device portion has an opening edge that is at least partly aligned along the first opening line portion and arranged on a first side of the opening line. The second opening device portion has an opening edge that is at least partly aligned along the second opening line portion and arranged on a second side of the opening line. In this way a consumer can fold the opening device at the fold line and force the opening edges of the first and second portions to act against each other to facilitate rupture of the packaging material along the opening line.
In one or more embodiments the first opening line portion is arranged to substantially coincide with the second opening line portion when the opening device is folded along the fold line.
In one or more embodiments the each of the first and second opening line portions is angled an angle with respect to the fold line.
In one or more embodiments the second opening line portion is a mirror of the first opening line portion around the fold line.
In one or more embodiments the first opening device portion has a fold edge that is at least partly aligned along the fold line and arranged on a first side of the fold line. Further, the second opening device portion has a fold edge that is at least partly aligned along the fold line and arranged on a second side of the fold line.
In one or more embodiments the fold edges are each arranged at a first distance from the fold line, to allow the opening device to be folded at the fold line.
In one or more embodiments the opening edges are each arranged at a second distance from the opening line to form an opening slot between them when the opening device is folded at the fold line.
In one or more embodiments the opening device comprises a third opening device portion and a fourth opening device portion. The third opening device portion is provided on the second side of the fold line and is a mirror of the first opening device portion around the fold line. The fourth opening device portion is provided on the first side of the fold line and is a mirror of the second opening device portion around the fold line.
In one or more embodiments the first and fourth opening device portions are connected to each other by a first bridge, and the second and third opening device portions are connected to each other by a second bridge, said bridges form ends of the opening slot.
In one or more embodiments the first and third opening device portions are connected to each other by a third bridge. The second and fourth opening device portions are connected to each other by a fourth bridge, and said bridges are arranged to form hinge areas when the opening device is folded along the fold line.
In one or more embodiments the first, second, third and forth opening device portions and the bridges together form a closed frame delimiting the opening slot.
In one or more embodiments the first opening device portion comprises a tab section.
In one or more embodiments the second opening device portion comprises a tab section.
In one or more embodiments the opening device is made of a polymeric material.
In one or more embodiments the opening device is provided with a pouring lip. The pouring lip is arranged on the second side of the opening line and is substantially centered in relation to the intersection point of the fold line and the opening line.
In one or more embodiments the opening device comprises a closure device for re-closing the packaging container after opening along the opening line. The closure device comprises at least a first closure device part and at least a second closure device part, said first and second closure device parts being provided on different sides of the first fold line, and said first and second closure device parts being provided with mutual lockable members such that the first and second closure device parts may be releasably locked to each other upon folding the packaging container along a second fold line thereby re-closing the packaging container.
In one or more embodiments at least one of the first or second closure device parts forms part of the second or fourth opening device portions.
In one or more embodiments the first closure device part forms part of the second opening device portion, and the second closure device part forms part of the fourth opening device portion.
In one or more embodiments one of the lockable members is formed as a loop and the other of the lockable members is formed as a protrusion adapted to be inserted into the loop for locking the first and the second lockable members together.
In one or more embodiments the loop and the protrusion are detachable from the packaging container.
In one or more embodiments the second fold line is parallel to the opening line, the second and fourth opening device portions are provided in between the opening line and the second fold line, on a first side of the second fold line, and the lockable members extend past the second fold line to a second side of the second fold line.
In one or more embodiments the second opening device portion and the hook are distanced from each other at least a distance corresponding to the distance between the opening line and the second fold line, and the hook and the second opening device portion are interconnected by an attachment portion attached to the packaging container.
According to a second aspect the invention comprises a method of manufacturing a packaging container with an opening device. Said method comprises the steps of
providing a packaging material comprising a bulk layer, which on a first side has a polymer layer,
moulding the opening device onto the first side of the packaging material, said opening device comprises a first opening device portion and a second opening device portion, wherein the first opening device portion is arranged on a first side of a fold line of the packaging container, and the second opening device portion is arranged on a second side of the fold line, thereby obtaining a packaging material comprising the opening device,
forming the packaging material into a tube by sealing overlapping longitudinal edges thereof,
filling the tube with a liquid or semi-liquid food product,
sealing the tube along transverse sealing zones to form a cushion-shaped packaging container, said sealing being made such that the packaging material is folded around the fold line in the sealing zones, and such that the opening device is positioned in one corner of the packaging container.
In one or more embodiments the step of moulding comprises the steps of: arranging, on the first side of the packaging material, a first mould portion comprising at least a first mould cavity, arranging a second mould portion on the other side of the packaging material, positioned opposite the first mould portion, injecting a plastic melt into the first mould cavity, and removing the first and the second mould portions.
In one or more embodiments the packaging material is a web for forming more than one packaging container, and the step of sealing comprises sealing the tube along transverse mutually apart sealing zones to form cushion-shaped packaging containers, and the method further comprises the step of separating the packaging containers from the tube by incisions in the sealing zones.
According to a third aspect the invention comprises a packaging container for liquid or semi-liquid food, wherein said packaging container is made of a longitudinal tube of packaging material which has been sealed off in the ends by first and second transverse sealing zones to form a cushion-shape. The packaging container has a fold line and an opening line, said fold line and opening line intersect in an intersection point. Said intersection point divides the opening line into a first opening line portion and a second opening line portion, and is provided with an opening device comprising a first opening device portion and a second opening device portion. The first opening device portion has an opening edge that is at least partly aligned along the first opening line portion and arranged on a first side of the opening line, and the second opening device portion has an opening edge that is at least partly aligned along the second opening line portion and arranged on a second side of the opening line, such that a consumer can fold the opening device at the fold line and force the opening edges of the first and second opening device portions to act against each other to facilitate rupture of the packaging material along the opening line.
Further advantages and favorable characterizing features will be apparent from the following detailed description. Equal or corresponding elements are denominated by the same reference numerous in all figures. The features described in connection with the different embodiments can be combined as far as technically possible. The embodiments will be described with reference to the appended figures, in which:
The first opening device portion 12 is arranged on a first, left side of the first fold line 16. Further is arranged on a first, upper side of the opening line 20. The second opening device portion 14 is arranged on a second, right side of the first fold line 16. Further it is arranged on a second, lower side of the opening line 20.
The first opening device portion 12 is elongate and has an opening edge 12a that extends along the first opening line portion 20a. The opening edge 12a is straight and substantially parallel to the first opening line portion 20a, i.e. the opening edge 12a is aligned along the first opening line portion 20a.
Correspondingly, the second opening device portion 14 is also elongate and has an opening edge 14a that extends along the second opening line portion 20b. The opening edge 14a is also straight, and is parallel to the second opening line portion 20b, i.e. it is aligned along the second opening line portion 20b.
The opening line 20 is an imaginary line along which the opening device will be opened, i.e. along which the packaging material of the packaging container will be ruptured or torn. The first fold line 16 is a longitudinal imaginary line along which the opening device can be folded during opening.
In this first embodiment the first opening line portion 20a is angled an angle α in relation to the first fold line 16. Similarly, the second opening line portion 20b is angled an angle α in relation to the first fold line 16. The angle may be in the range 20-90°, particularly 45-90°. Together the first and second opening line portions 20a, 20b together form an obtuse V-shape.
In the first embodiment the first opening device portion 12 is further comprising a fold edge 12b. The fold edge 12b is aligned along the first fold line 16, i.e. it is parallel to the first fold line 16. Correspondingly, the second opening device portion 14 comprises a fold edge 14b. That fold edge 14b is also aligned with the first fold line 16, i.e. is parallel to the first fold line 16.
As can be seen from
Further, the fold edges 12b, 14b of the first and second opening device portions 12, 14 are each arranged at a first distance from the first fold line 16. The distance is in the range of 1-2 mm.
The distance facilitates folding of the opening device 10 around the first fold line 16.
Furthermore, the opening edges 12a, 14a of the first and second opening device portions 12, 14 are each arranged at a second distance from the opening line 20. The distance is in the range of 0.2-1 mm.
The distance facilitates rupture of the packaging material along the opening line.
The first and second opening device portions 12, 14 are provided with tab sections 34 providing an area where a consumer can grab the opening device with his or her fingers. The tab sections 34 may be provided with a tactile pattern in order to facilitate gripping. The tab sections 34 in this first embodiment have a convex shape.
A further difference compared to the second embodiment is that the first distance is shorter, i.e. the distance from the first fold line 16 to the fold edges of the first, second, third and fourth opening device portions.
Preferably, the opening device 10 is injection-moulded or glued onto the packaging material, preferably to what will become the outside surface of a packaging container. The material thickness t of the opening device, in a direction perpendicular to the packaging material surface, is in the range of approximately 0.2-2 mm. However, the thickness may be made larger than 2 mm, but the opening device would then require more material, thereby increasing cost. The corresponding packaging material thickness used for this type of opening device is today in the range of approximately 0.2-1.5 mm. However, the opening device may be provided on thinner as well as thicker packaging materials.
The packaging container 100 is made of a longitudinal tube of packaging material which has been sealed off in the ends by first and second transverse sealing zones 36 to form a cushion-shape. In the sealing zones inner heat sealable layers of the packaging material have been sealed together to form a tight seal. As the packaging containers are of the pouch type it does not have any defined longitudinal edges. However, at outermost edges 38 of the transverse sealing zones 36 the packaging material is folded, since the transverse sealing is made transverse to a tube. The first fold line 16 previously referred to is an imaginary line extending longitudinally from an upper outermost edge 38a of a first transverse sealing zone 36a to a corresponding, lower outermost edge 38b of a second transverse sealing zone 36b. The first fold line 16 extends the shortest possible distance between the edges 38a, 38b.
The packaging container 100 is filled with a liquid or semi-liquid food product. The term “liquid or semi-liquid food” generally refers to food products having a flowing content that optionally may contain pieces of food. Dairy and milk, soy, rice, grains and seed drinks, juice, nectar, still drinks, energy drinks, sport drinks, coffee or tea drinks, coconut water, tea drinks, wine, soups, jalapenos, tomatoes, sauce (such as pasta sauce), beans and olive oil are some example of food products contemplated.
With reference to
Upon opening a consumer will typically grip around the upper tab sections 34a with the index finger and the thumb of one hand and similarly grip around the lower tab sections 34b with the other hand. By doing so the consumer can fold the opening device 10 at the first fold line 16. By further forcing the upper tab sections away from the lower tab sections, in the directions shown by the arrows, the opening edges of the first and third opening device portions will act against the opening edges of the second and fourth opening device portions in order to initially break the packaging material in the intersection point, and then facilitate rupturing the packaging material along the opening line 20. The edges will act as scissors blades.
To further facilitating the rupture along the opening line 20 it may be considered to provide the opening line as a weakening line, such as for example a line at which one or more of the packaging material layers have been perforated or in other way been weakened.
Further, the second and fourth opening device portions 14, 24, i.e. the lowermost opening device portions, and the fourth bridge 32 are provided with a pouring lip 40, i.e. an element protruding from the opening device and the packaging container along a central portion of the opening line 20. The pouring lip extends from the first fold line 16 and along each of the first and second opening line portions 20a, 20b. The pouring lip 40 extends a distance, on each side of the first fold line 16, substantially corresponding to a substantial portion of the width of the tab sections 34. In
Going back to
Although the opening device is attached to the packaging material of the packaging container it is advantageous if the tongue and the loop is easily detachable from the packaging material such that the consumer can easily pull the loop over the tongue. If the opening device is moulded, which will be described later, onto the packaging material the mould may be cooled locally at the lockable members. Another alternative is that the packaging material is locally coated with a material that will cause less adhesion between the packaging material and the lockable members.
As can further be seen in
By means of the closure device 42 the packaging container is re-closable. A first step towards re-closure is to fold the remaining portions of the opening device 10, i.e. the second and fourth opening device portions 14, 24, over the second fold line 50 following arrows r. The second opening device portion 14 will then be hidden inside the fold whereas the fourth opening device portion 24 will be visible on the front face of the packaging container. A second, and final, step towards re-closure is to lock the lockable members 48, i.e. in this case force the hook over the tongue. As seen in the figure the tongue will be freely extending from fourth opening device and pointing upwards in the figure. The hook can be pulled, by means of the hinge area 56, upwards towards the tongue. The reclosed state is shown in
In the following manufacturing of the packaging container with the opening device will be described.
A first step of the method is to provide a packaging material. The packaging material generally comprises a bulk layer, which on a first side has a polymeric layer. The bulk layer can be a paper or paperboard layer. The bulk layer is arranged to provide for the greatest contribution to the flexural rigidity of the laminate. The paper or paperboard used herein has a typical grammage between 50-250 g/m2, particularly between 60-220 g/m2, depending on the requirement for different types of packaging containers. The grammage of the paperboard is assessed in accordance with ISO 536. Grammage expresses weight per unit area and is measured in g/m2. The paper or paperboard normally has a thickness between 80-300 μm, particularly between 90-290 μm 80-660 μm, and is appropriately selected in order to obtain the desired stiffness suitable for the type of packaging container and the intended food product. The bulk layer thickness can be assessed by microscopy. It is however also conceivable that the bulk layer of the packaging material instead is a polyolefin bulk layer, made e.g. of polyethylene, polypropylene or copolymers of ethylene or propylene, such as, for example, ethylene-propylene, ethylene-butene, ethylene-hexene, ethylene-alkyl(meth)acrylate or ethylene-vinyl acetate copolymers, or PET (polyethylene terephthalate) bulk layer.
The polymeric layer is a décor layer which is to be the outer side of the filled and sealed packaging container. The side of the bulk layer, e.g. paper or paperboard, which is to be the outer side of the closed and sealed packaging container can contain a print covered by the decor layer. The decor layer is a heat-sealable polyolefin layer facing the surrounding environment of the resulting packaging container. Suitable polyolefins are polyethylene of the low density type, selected from the group consisting of LDPE, LLDPE, VLDPE, ULDPE or mLLDPE and blends of two or more thereof, optionally other polyolefins such as high density polyethylene (HDPE), polypropylene or propylene co- or ter-polymers are useful as the layer facing the surroundings. The decor layer provides additional protection and stability to the packaging container.
In addition, the packaging material comprises an innermost heat-sealable layer of a heat-sealable polyolefin polymer which is applied as a layer to be directed towards the inside of the packaging container, i.e. in direct food contact. The heat-sealable layer for the innermost layer may suitably be a polyethylene polymer of the low density type, selected from the group consisting of LDPE, LLDPE, VLDPE, ULDPE or mLLDPE and blends of two or more thereof. Depending on the type of packaging containers produced from the packaging material, also heat-sealable innermost layers of high density polyethylene, polypropylene or propylene co- or ter-polymers are conceivable.
Furthermore, the packaging material may comprise a barrier layer, such as an oxygen barrier, for instance aluminium foil, as well as suitable adhesion layers to increase adherence between the layers. The barrier layer is arranged by help of a laminate layer on the side opposite the bulk layer and has an adhesive on the side opposite the laminate layer. The adhesive depends on the type of bulk layer and the barrier layer and are within the capacity of those skilled in the art to select.
One exemplary packaging material comprises a decor layer which on one side of the layer has a paperboard layer, said paperboard layer, on the side opposite the decor layer has a laminate layer, said laminate layer, on the side opposite the paperboard layer has an oxygen barrier, said oxygen barrier, on the side opposite the laminate layer has an adhesive, and said adhesive, on the side opposite the oxygen barrier has a heat-sealable layer.
Laminated packaging materials are obtained by various methods for laminating layers together, such as extrusion lamination, dry adhesive lamination, heat-pressure lamination, and may also be including various coating methods. Although to achieve the benefits the particular lamination technique is not crucial it is considered to be of particular use in extrusion lamination to produce laminated packaging materials, in particular carton-based packages used for food such as liquid and semi-liquid food.
The term “heat-sealing” used above refers to the process of sealing of a thermoplastic material with another. Thus a heat-sealable material should be able to generate a seal when put in contact with another suitable thermoplastic material under the appropriate conditions such as when applying sufficient heating. Suitable heating can be achieved by induction heating or ultrasonic heating or other heating means.
A second step in the manufacturing method is that of moulding the opening device onto the first side of the packaging material. As described in relation to the various embodiments above said opening device comprises at least a first opening device portion 12 and a second opening device portion 14. The first opening device portion 12 is arranged on a first side of a fold line 16 of the packaging container, and the second opening device portion 14 is arranged on a second side of the fold line. The moulding step comprises the sub-steps of arranging, on the first side of the packaging material, a first mould portion comprising at least a first mould cavity, arranging a second mould portion on the other side of the packaging material, positioned opposite the first mould portion, injecting a plastic melt into the first mould cavity, and removing the first and the second mould portions. The material of the opening device is suitable for thermoplastic moulding, more specifically injection moulding, and may be polyethylene, polypropylene or another plastic suitable for injection moulding, for example polyethylene terephthalate. The first side of the packaging material is the side which will become the outer side of the packaging container, the first side having the décor layer. The heat of the melt will anchor or weld the opening device to the outer décor layer of the packaging material.
The first mould portion, or mould half has, as described above, at least one mould cavity. The first mould portion may comprise several cavities depending on the opening device. For instance, for the embodiment shown in
The dimensions of the opening device may be optimized to achieve an adequate opening of the packaging container only and any surplus use of material may be avoided. In this way only a relatively small amount of plastic is needed (compared to known opening devices). This has the beneficial effect that the time needed for injection is small, yet it also has the effect that the mould does not have to be closed for very long since the plastic will start to freeze (or solidify) immediately. The small amount of plastic vouches for that even if only a surface layer has started to freeze, this will be enough to retain the shape of the opening device until it has fully frozen, which in turn implies that the mould will be opened basically as soon as the injection is finalized. An outermost skin layer of the plastic melt will freeze as soon as it contacts the walls of a mould cavity, or the outermost layer of the packaging material. For non-complex designs this vouches for that the mould may be opened as soon as it is filled. For more complex designs, e.g. designs incorporating steep edges or distinct ridges more time may have to be allocated for the plastic to freeze, such that the plastic is allowed to solidify from the skin and inwards before opening the mould. In this context it should be understood that the plastic will shrink (from the outside and inwards) as it freezes, and in a conventional injection molding process it is known to continue to inject plastic during the freezing, such that the finished detail is a replica of the mould cavity. It may also be important to realize that the longer the mould remains closed, the more heat will be transferred from the melt to the mould. This results in a need for installing a cooling arrangement, such as channels for leading cooling fluid through the mould portions. For the present invention such arrangements may not be necessary due to the inherently low cycle times.
Though there is no drawing of a mould or mould cavity the skilled person realizes that the shape of the mould cavity will correlate to the shape of the manufactured opening device (or rather—vice versa), and since the present invention is not directed to the shaping of mould cavities this will not be described any further. Also, injection moulding is a well-established technique not the least for some of the suggested materials: PE, PP and PET. Therefore a disclosure of an injection moulding process or features thereof is not considered essential for the skilled person to apply the present invention, and it is therefore omitted.
After moulding the packaging material comprises the opening device and it is time to form the packaging material into packaging containers. The packaging material is formed into a tube by sealing overlapping longitudinal edges thereof. Either the packaging material is loaded into the filling machine as a continuous web which will be formed into several packaging containers, or the packaging material is loaded to the filling machine as blanks. In the latter case a sleeve-formed tube is formed by each blank.
The next steps are filling and sealing. In the case of a packaging material in the form of a blank, the sleeve-formed tube is in one end sealed along a transverse sealing zone and thereby filled with the liquid or semi-liquid food product. The still open end is then sealed along a transverse sealing zone. In the case of a web-based filling machine, like for instance the Tetra Fino® Aseptic-type packaging machine the tube is continuously filled and sealed along transverse mutually apart sealing zones to form cushion-shaped packaging containers. In this case the method further comprises the step of separating the packaging containers from the tube by incisions in the sealing zones.
Each transverse sealing is made such that the packaging material is folded around the fold line 16 in the sealing zones 36. Further, the position of the opening devices in relation to the transverse sealing inductors are controlled such that an opening device is positioned on each package and preferably in one corner of the finished packaging container, see
It is apparent to a person skilled in the art that with the advancement of technology, the basic idea may be implemented in various ways. The invention and its embodiments are thus not limited to the examples described above; instead they may vary within the scope of the claims.
For example, in the
A couple of examples of tab section designs have been shown in the embodiments, however, it is to be understood that the tab sections may be designed in many ways depending on the type of package the opening device is provided to and the amount of polymeric material that can be allowed for the opening device, typically 0.1-1 g.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1450773-5 | Jun 2014 | SE | national |
| 1450774-3 | Jun 2014 | SE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2015/058621 | 4/22/2015 | WO | 00 |
