Method and apparatus for producing laminated packaging material

Abstract

The present disclosure relates to a method for manufacturing a laminated packaging material (16) capable of forming a packaging container (10) for packaging a liquid food product (12), the method comprising providing a bulk layer (22) of paper or paperboard or other cellulosic material having at least one through hole (24), providing a substrate layer (26) and an adhesive (30) formed or applied to a lamination surface (28) thereof, positioning the bulk layer (22) and the substrate layer (26) such that the adhesive (30) faces the lamination surface (32) of the bulk layer (22) and such that the substrate layer (26) is disposed in front of the at least one through hole (24), bonding the bulk layer (22) and the substrate layer (26) in a lamination unit (38), and forming a first lamination means (40) therebetween. 2), the substrate layer (26), the bulk layer (22) and the second laminating means (44) are kinematically arranged in the order listed, a laminating pressure (48) is generated between the first and second laminating means (42; 44), at least one non-adhesive laminating means (46) is kinematically arranged between the second laminating means (44) and the bulk layer (22), and the position (50) of the bulk layer (22) and / or the position (50) of the at least one non-adhesive laminating means (46) are controlled such that at least one through hole (24) is covered by the at least one non-adhesive laminating means (46) as long as the laminating pressure (48) is applied to the at least one through hole (24). The disclosure further refers to a respective apparatus (36) for carrying out the method.

Description

[Technical field]

[0001] The present invention relates to a method for producing a laminated packaging material capable of forming a packaging container for packaging liquid food products, to a laminated packaging material produced by such a method, and also to an apparatus suitable for carrying out said method. [Background technology]

[0002] Disposable packaging containers for liquid foods are often manufactured from packaging laminates based on paperboard or carton. Such packaging containers are often used to package liquid foods such as milk or fruit juices that are sold for long-term shelf life. The packaging material of such known packaging containers is typically a laminate comprising a bulk or core layer of paper, paperboard or other cellulosic material and an outer liquid-tight layer of thermoplastic plastic. To make the packaging container gas-tight, in particular oxygen gas-tight for aseptic packaging purposes, the laminates of these packaging containers usually comprise an additional barrier layer, e.g. aluminum foil or other films with a barrier function, such as polymer-based and / or paper-based films.

[0003] On the inside of the laminate, in other words the side intended to face the food contents filled in the container made from the laminate, there is usually an innermost layer applied onto the barrier layer. The innermost layer comprises, for example, an adhesive polymer and / or a heat-sealable thermoplastic polymer such as a polyolefin, and may comprise one or several partial layers. And on the outside of the bulk layer there is usually an outermost heat-sealable polymer layer.

[0004] Packaging containers are generally produced by modern high-speed packaging machines of the type that form, fill and seal packages from webs or from prefabricated blanks of packaging material. Thus, packaging containers may be produced by joining together a web of laminate packaging material at both longitudinal edges of the web with overlapping joints made by welding together the inner and outermost heat-sealable thermoplastic polymer layers and reforming it into a tube. The tube is filled with the desired liquid food product and then divided into individual packages by repeating transverse sealing of the tube at a predetermined distance from each other below the level of the contents in the tube. The packaging material is separated from the tube by scoring along the transverse seals and given the desired geometric shape (usually a parallelepiped) by creasing the packaging material along prepared crease lines.

[0005] Packaging containers for sensitive liquid foods, e.g. milk and juice, can also be produced from sheet blanks or prefabricated blanks of laminate packaging material. Packaging containers are produced from tubular blanks of flat-folded packaging laminate by stacking the blanks to form an open tubular container capsule, one of whose open ends is closed by folding and heat sealing an integral end panel. The container capsule thus closed is filled through its open end with the food, e.g. juice, and is then closed by further folding and heat sealing of the corresponding integral end panel. Examples of packaging containers produced from sheet and tubular blanks are the conventional so-called gable-top packages. Packages of this kind can also have a molded top and / or a screw cap made of plastic.

[0006] In order to access liquid food contained in a packaging container, it is often necessary to pierce the laminate packaging material, for example by a straw. Therefore, it is well established in the relevant art to provide a prefabricated hole that penetrates at least a portion of the material of the laminate packaging material. Such a straw hole or other opening structure allows the consumer to conveniently access the contents of the packaging container after piercing the remaining material. Such a hole is provided, for example, by punching a hole in the bulk layer or core layer before lamination, and is therefore often called a prepunched hole, which is then covered on the inside and outside by additional laminate layers.

[0007] Since the formation of prepunched holes is often performed before the lamination process in which liquid or viscous materials such as melt layer materials or adhesives may be used, it is necessary to prevent such materials from spreading uncontrollably through the holes. For example, if the bulk layer is provided with through holes and applied to the substrate layer in the lamination process, the adhesive should only affect the respective lamination surfaces of the bulk layer and the substrate layer. However, when bonding under lamination pressure, such materials may be extruded from the through holes and reach the surface opposite to the lamination surface of the bulk layer. This may lead to further problems such as the material sticking to the lamination device placed on the opposite surface.

[0008] For example, patent document WO2015 / 193632A1 proposes a lamination station in which the nip rollers of the lamination station and the through holes formed by the laminate layer are separated by a non-adhesive belt. This belt is pressed against the area of ​​the holes and the lamination pressure acts on the area. Thus, material from inside the holes is prevented from escaping and reaching the nip rollers.

[0009] However, the proposed system lacks flexibility and efficiency since changing the placement of the holes relative to the nip rollers requires interrupting the production process and readjusting the system with respect to the placement of the belt.

[0010] Therefore, there is a need for improved methods and respective production apparatus for laminate packaging materials. Summary of the Invention [Problem to be solved by the invention]

[0011] It is now an object of the present invention to at least partially overcome one or more of the above identified limitations of the prior art. In particular, the present invention aims to provide a method for manufacturing a laminated packaging material capable of forming a packaging container for packaging liquid food products, which allows a bulk layer having a through hole to be safely and efficiently laminated to a substrate layer, and which allows the use of liquid, viscous or formable adhesive or layer materials. In particular, it aims to prevent the influence of such materials on the laminating equipment.

[0012] In order to achieve this object, a method for producing a laminated packaging material capable of forming a packaging container for packaging liquid food products is provided. The method of the present invention comprises the steps of: - providing a bulk layer of paper or paperboard or other cellulosic material having at least one through hole; - providing a substrate layer and an adhesive formed or applied to its laminating surface; - positioning the bulk layer and the substrate layer such that the adhesive faces a lamination surface of the bulk layer and such that the substrate layer is positioned in front of the at least one through hole; - joining the bulk layer and the substrate layer with a lamination unit, the first lamination means, the substrate layer, the bulk layer and the second lamination means being kinematically arranged in the recited order, a lamination pressure being generated between the first lamination means and the second lamination means, and at least one non-adhesive lamination means being kinematically arranged between the second lamination means and the bulk layer; Be prepared to do so.

[0013] According to the present invention, the position of the bulk layer and / or the position of the at least one non-adhesive laminating means is controlled at least as long as laminating pressure is applied to the at least one through hole so that the at least one through hole is covered by the at least one non-adhesive laminating means.

[0014] Reference may be made herein to a disclosed feature in the singular as "at least one" merely for the purpose of expediently describing technical principles, but this is not intended to be of a limiting nature.

[0015] The method of the present invention has the beneficial effect that the through-holes are safely sealed by the non-adhesive laminating means, preventing any material, such as adhesive, from passing through the through-holes to the second laminating means. This effect can also be achieved without stopping the manufacturing process, for example to readjust the position of the non-adhesive laminating means, since the relative positions of the bulk layer and the non-adhesive laminating means are controlled. Thus, both the quality and productivity of the method of the present invention are at a very high level.

[0016] The bulk layer and the substrate layer are generally joined by a lamination process, for example a dry lamination or a wet lamination process. Preferably, the joining may be performed by a dispersion and / or wet lamination process.

[0017] Controlling the position of the bulk layer and / or the position of the non-adhesive laminating means may be an open or closed control loop, preferably performed in real time. The control of the position may refer to any dimension necessary to describe the relative position of the through-hole and the non-adhesive laminating means. In case the non-adhesive laminating means and the through-hole meet, for example temporarily, in a plane parallel to the plane in the laminating unit, such dimension may comprise the lateral and / or longitudinal dimension of said plane. In case the non-adhesive laminating means and the through-hole approach each other, for example temporarily, in a non-parallel plane, such dimension may comprise the lateral and / or longitudinal dimension of said respective planes, and may also comprise the longitudinal dimension in order to predict the position of the through-hole relative to the non-adhesive laminating means when laminating pressure is applied. The respective control technique may use suitable means for processing such two-dimensional or three-dimensional data, and may also process time data relating to position, velocity and / or acceleration values, if necessary. A person skilled in the art would have sufficient technical knowledge to select from the above suggestions or any combination or derivation thereof to ensure that the through holes are safely covered by the non-adhesive laminating means, as enabled by the present disclosure, preventing adhesive material from progressing through the through holes to the second laminating means.

[0018] The bulk layer and the substrate layer may be introduced into the laminating device separately or as a pre-bonded composite layer. Preferably, they are introduced separately and brought into contact in the laminating unit. It is to be understood that, for example, through holes can be produced in a preliminary step of the method of the invention. The same applies to the application of adhesive to the substrate layer or the formation of the substrate layer. It is preferred, but not technically essential, to carry out the method of the invention as a flow process. The bulk layer, the substrate layer, or both layers may themselves have some liquid-resistant properties. It is also possible and preferred to apply further layers or further layers, such as liquid-resistant layers or oxygen barriers, in subsequent steps of the method of the invention, based on the generally known requirements for such laminated packaging materials.

[0019] The through-hole may preferably serve as a hole for inserting a straw therein, and may therefore have a suitable diameter, for example a diameter of about 6 mm.

[0020] Preferably, the substrate layer may comprise a material such as paper, paperboard, other cellulosic materials, polymeric materials, or any combination thereof. In particular, it is preferred to provide a substrate layer comprising a polyolefin.

[0021] The adhesive material can be selected from among all materials known to be suitable for such lamination processes, preferably wet lamination processes. The material of the substrate layer may itself have adhesive properties, for example if the substrate layer comprises a polymer layer. The adhesive may also be applied to the substrate layer as an additional material, for example as a polymer solution. The adhesive is applied at least in the region of the through-hole, ensuring a liquid-resistant adhesion in that region, for example if the through-hole is to be pierced by a straw. It is particularly preferred to apply the adhesive to the entire lamination surface of the substrate layer, in order to achieve a comprehensive bond between the bulk layer and the substrate layer in general.

[0022] Preferably, the laminating unit is a wet laminating unit for bonding the bulk layer and the substrate layer in a wet lamination process.

[0023] The term "kinematically arranged" does not mean that the first lamination means, the substrate layer, the bulk layer and the second lamination means are necessarily arranged in direct physical contact with each other in that order (although it is possible), but that the lamination pressure is propagated between the respective components in that order. The arrangement of the non-adhesive lamination means and the second lamination means is similar, but the bulk layer is in direct physical contact with the non-adhesive lamination means to seal the through-holes against the adhesive on the side opposite the lamination side of the bulk layer. However, it is preferred to arrange the above-mentioned components in direct physical contact in the following order: first lamination means, substrate layer, bulk layer, non-adhesive lamination means, second lamination means. This allows the bulk layer to be in direct contact with the second lamination means, at least partially, at the same time. This also applies to the areas of the second lamination means where the non-adhesive lamination means does not extend. This is because the non-adhesive laminating means does not necessarily separate the entire surface of the second laminating means from the bulk layer, but is preferably limited to the area of ​​the through holes.

[0024] The term "non-adhesive laminating means" refers to any technical means suitable to cover the through-holes and prevent the adhesive from escaping through the through-holes on the side of the bulk layer opposite the laminate side, or at least to prevent the adhesive that may escape through the through-holes on the side of the bulk layer opposite the laminate side, from adhering to a second laminating means, in particular with respect to the laminating pressure applied. Preferably, the non-adhesive laminating means may comprise a material such as polytetrafluoroethylene (PTFE), also known as the TEFLON® brand, or other materials of similar properties that protect against sticking.

[0025] In a preferred embodiment of the method of the present invention, the bulk layer comprises a plurality of through holes, and furthermore a plurality of non-adhesive laminating means are kinematically arranged between the second laminating means and the bulk layer, and the position of the bulk layer and / or the position of each non-adhesive laminating means is controlled such that each non-adhesive laminating means covers the through hole at its respective position at least as long as laminating pressure is applied to each through hole.

[0026] This further increases the flexibility of the method of the invention. The through holes may be arranged, for example, in one or several rows on the bulk layer. For example, each non-adhesive laminating means may be controlled according to the position of a through hole in one of these lines. The through holes in the row may be at least partially periodic or non-periodic. The through holes may be arranged in groups, randomly, equidistantly or at different distances, and may be of different sizes and shapes.

[0027] In a preferred embodiment of the method of the present invention, each of the first and second laminating means comprises a laminating roller transmitting a laminating pressure, and the position of the bulk layer and / or the position of the non-adhesive laminating means is controlled at least in a direction parallel to the rotation axis of the laminating roller. The laminating roller may comprise, for example, a nip roller and a chill roller.

[0028] In a preferred embodiment of the method of the present invention, the non-adhesive laminating means comprises a non-adhesive belt guided over laminating rollers constituted by the second laminating means.

[0029] For example, based on the cylindrical geometric shape of the lamination roller, it can be realized in an easy manner to control the movement of the belt along said shape in order to change its position.

[0030] Preferably, one or more additional rollers are used, such as, for example, tension rollers, idling rollers, cooling rollers or storage rollers, either on the belt, on the laminate packaging material, or on any additional materials used to produce the laminate packaging material.

[0031] The belt may be driven by one or more of such additional rollers and / or the laminating rollers of the second laminating means.

[0032] The use of rollers for both the second laminating means and for driving the belt reduces the effort required to synchronize the movement of the belt with the laminated packaging material, for example when subjected to lamination pressure.

[0033] Preferably, eight belts of the above-mentioned type are arranged adjacent to each other in a direction parallel to the axis of rotation of the lamination roller. Preferably, each of the eight belts is movable in that direction by a range of 30 cm. Preferably, the two outermost belts are characterized by being wider than the other belts arranged between them, which means that the intermediate belts are each narrower than the end belts.

[0034] In a preferred embodiment of the method of the present invention, the position of the belt in a direction parallel to the axis of rotation of the laminating rollers is controlled by an actuating guide member which exerts a positioning force on the belt in a direction parallel to the axis of rotation of the laminating rollers.

[0035] When the belt is guided over laminating rollers that may rotate simultaneously, positioning forces can cause the belt to easily change position on the laminating rollers.

[0036] For example, the belt itself can be driven by an electric motor, which can also be used to generate the positioning force. Preferably, for each belt there is at least one individually controlled actuator, such as an electric motor. Further by way of example, the actuator guide member may comprise a guide sleeve for guiding the belt, or may comprise other structures for transmitting the positioning force. The actuator guide member, e.g. a guide sleeve, is preferably designed to take into account the fact that the belt may be driven in a direction perpendicular to the direction of the positioning force. Therefore, the actuator guide member may comprise bearings to compensate for the relative movement between the belt and the guide structure.

[0037] Preferably, the actuating guide members may have at least one or more guide rollers carried on individual supports for each of the belts. Preferably, this support, and therefore the actuating guide members, comprises a dedicated motor driven in the direction of the positioning force and / or transverse to the positioning force. All guide members may be driven individually in the direction of the positioning force on a single slide or track. Also, multiple slides or tracks may be provided for carrying a group of guide members and belts, respectively. Also, multiple slides or tracks may be provided for carrying one guide member and belt, respectively.

[0038] In a preferred embodiment of the method of the present invention, the method is a continuous or discontinuous flow process carried out in the machine direction, and the position of the bulk layer and / or the position of the non-adhesive laminating means is controlled at least transverse to the machine direction.

[0039] Machine direction refers to the fact that laminate packaging materials are typically produced in a flow process that has a material feed direction, or machine direction.

[0040] In a preferred embodiment of the method of the present invention, after joining the bulk layer and the substrate layer, the laminated packaging material is guided through at least one subsequent roller provided with a non-adhesive laminating means which covers the through holes as long as the subsequent roller is in contact with the through holes.

[0041] The non-adhesive laminating means of the trailing roller may be of similar design and construction as described above and therefore may be controllable to match the location of the through holes.

[0042] This ensures that, for example, adhesive that has not yet achieved a sufficient degree of hardening does not adhere to the following roller.

[0043] In a preferred embodiment of the method of the present invention, a sensor detects the position of the through-hole on the bulk layer, and based on the detected position of the through-hole the position of the bulk layer and / or the position of the non-adhesive laminating means is controlled.

[0044] This greatly improves the process stability and flexibility of the method of the present invention with respect to repositioning of the through-holes.

[0045] In a preferred embodiment of the method of the present invention, the non-adhesive laminating means is cleaned by a cleaning device before and / or after contacting the through holes. Preferably, the cleaning device is located at a position where the non-adhesive laminating means, e.g. the belt, has passed the first and second laminating means. In one embodiment, the cleaning device is located after the nip rollers where the belt exits the nip defined by the nip rollers.

[0046] The cleaning device ensures that impurities or unavoidable residues of the adhesive material applied to the non-adhesive laminating means are removed before the non-adhesive laminating means is again brought into contact with the bulk layer and the second laminating means, on which basis it is particularly preferred to combine a cleaning device with the wet laminating process.

[0047] The cleaning device may preferably be combined with an actuating guide member. For example, such a cleaning device may be combined with a guide sleeve for the belt. Preferably, the guide sleeve comprises a cleaning device for cleaning the belt when the belt is driven transversely to the direction of the positioning force, for example towards the second laminating means, in a particular example in the machine direction.

[0048] The cleaning device may comprise a scraper or similar structure for scraping off excess adhesive that may remain on the non-adhesive laminating means, preferably the belt, and may further comprise a collection vessel for collecting excess adhesive, particularly the scraped off adhesive.

[0049] Additionally, the non-adhesive laminating means, preferably the belt, may be exposed to a cleaning bath, for example immersed in the cleaning bath. The cleaning bath may preferably comprise water and alcohol. Most preferably, the cleaning bath is applied after the scraper has been used.

[0050] After the wash bath, the non-adhesive laminating means, preferably the belt, is dried, preferably by suitable heat treatment means.

[0051] In a preferred embodiment of the method of the present invention, after joining the bulk layer and the substrate layer, at least one additional layer is applied to the laminate packaging material, which additional layer comprises an innermost liquid-tight layer in direct contact with the food contained by the packaging container that can be formed from the packaging material and / or an outermost liquid-tight layer suitable for constituting the outside of the packaging container.

[0052] Based on the target product, especially the packaging container for liquid food, other layers such as oxygen barrier may be applied as additional layers.

[0053] Another aspect of the present invention relates to a laminated packaging material produced by the inventive method according to the present disclosure.

[0054] Yet another aspect of the present invention relates to a packaging container comprising the inventive laminate packaging material according to the present disclosure.

[0055] Yet another aspect of the present invention relates to an apparatus for manufacturing laminated packaging material capable of forming a packaging container for packaging liquid food, the apparatus comprising a laminating unit configured to receive a bulk layer having at least one through hole and a substrate layer having an adhesive formed or applied to its laminating surface, the laminating unit comprising first and second laminating means configured to form a laminating cavity therebetween and to apply a laminating pressure to the bulk layer and the substrate layer when the layers are introduced into the laminating cavity, the laminating unit further comprising at least one non-adhesive laminating means kinematically disposed between the second laminating means and the bulk layer when the laminating unit is introduced into the laminating cavity.

[0056] According to the present invention, the position of the bulk layer and / or the position of said at least one non-adhesive laminating means is controllable so that at least one through hole is covered by at least one non-adhesive laminating means, and at least one through hole is covered by at least one non-adhesive laminating means as long as laminating pressure is applied to the at least one through hole.

[0057] In a preferred embodiment of the inventive device, the device may be adapted and configured to carry out the inventive method according to the present disclosure. More preferably, the inventive device is configured to carry out the inventive method.

[0058] Based on the above, all apparatus-related features disclosed with respect to the inventive method are also disclosed herein as analogous features in possible embodiments of the inventive apparatus, and vice versa for method-related features disclosed with respect to the inventive apparatus.

[0059] Preferably, the lamination unit of the apparatus of the present invention is a wet lamination unit.

[0060] Preferably, the device of the present invention comprises a sensor which may be configured to detect the position of the through-hole on the bulk layer, and based on the detected position of the through-hole the position of the bulk layer and / or the position of the non-adhesive laminating means is controllable, more preferably the sensor is so configured.

[0061] In a preferred embodiment of the apparatus of the present invention, the apparatus is configured to produce laminated packaging material in a continuous or discontinuous flow process carried out in the machine direction, and the position of the bulk layer and / or the position of the non-adhesive laminating means is controllable at least in the direction perpendicular to the machine direction.

[0062] Further objects, features, aspects and advantages of the present invention will become apparent from the following detailed description and drawings. [Means for solving the problem]

[0063] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: FIG. [Brief description of the drawings]

[0064] [Figure 1] FIG. 1 is a diagram showing one embodiment of a container for packaging liquid food. [Diagram 2] FIG. 1 is a cross-sectional view of one embodiment of a laminate packaging material from which a package can be formed. [Diagram 3] 1 is a diagram showing an embodiment of a method for producing a laminate packaging material of the present invention with reference to a laminate packaging material production apparatus. [Figure 4] 1 is a diagram showing an embodiment of a method for producing a laminate packaging material of the present invention with reference to a laminate packaging material production apparatus. [Diagram 5] 5 shows an alternative embodiment of the device shown in FIG. 4, particularly with regard to a different design of the slide. [Figure 6] FIG. 1 illustrates an embodiment of a cleaning device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0065] With reference to Figure 1, one embodiment of a packaging container 10 for a liquid food 12 is shown. For example, a packaging container making machine 14, not further specified, may provide a laminated packaging material 16 (see Figures 2-4) from which the packaging container 10 is made. The packaging container 10 may be exemplarily made by cutting and sealing the laminated packaging material 16 by respective cutting and sealing means 18 after filling with the liquid food 12. The scope of the present invention covers the inventive packaging container 10 thus formed from the inventive laminated packaging material 16, as further described with reference to Figures 2-4.

[0066] For purposes of further illustrating the present invention, a machine direction 20 is defined in Figure 1 and will be referenced in the following figures. By machine direction 20, it is meant that the laminated packaging material 16 is typically produced in a flow process having a material feed direction, in other words, a machine direction 20.

[0067] FIG. 2 shows the laminate packaging material 16 of the present invention in more detail. The laminate packaging material 16 comprises a bulk layer 22 of a cellulosic material, such as paper or paperboard. The bulk layer 22 is provided with at least one through hole 24. The bulk layer 22 is joined to a substrate layer 26, the laminate surface 28 of which comprises an adhesive 30 for adhering the substrate layer 26 to the laminate surface 32 of the bulk layer 22. The adhesive 30 is, by way of example only, a polymer solution applied to the already dried laminate surface 28 of the laminate packaging material 16 shown in FIG. 2. It should be noted that the material of the substrate layer 26 may provide adhesive properties by itself, for example when provided in the form of a molten polymer material. If the substrate layer 26 provides adhesive properties by itself, the adhesive 30 does not necessarily need to be applied additionally to the laminate surface 28. As can be seen, the adhesive 30, or in other embodiments the material of the substrate layer 26, respectively, penetrates to some extent into the through hole 24. This is believed to be a result of the lamination pressure 48 (see FIG. 3) applied to bond the bulk layer 22 and the substrate layer 26. For example, as long as the adhesive 30 is not yet dry, such lamination pressure 48 may cause the adhesive 30 to rise up in the through-holes 24 and reach the side 34 of the bulk layer 22 opposite its lamination surface 32 (compare FIG. 3). However, this is undesirable. When the lamination pressure 48 is reduced, the height level of the adhesive 30 in the through-holes 24 may sink again and have the structural properties shown. This sinking effect is enhanced as the adhesive 30 dries, which may cause a further shrinkage in volume of said adhesive 30. The laminated packaging material 16 of the present invention is manufactured by the method of the present invention as described below.

[0068] Figure 3 shows diagrammatically the inventive method for producing the laminated packaging material 16 with reference to an inventive apparatus 36 (compare also Figures 4 to 6) for producing the laminated packaging material 16. In Figure 3, a lamination unit 38 of the apparatus 36 is shown diagrammatically. The inventive method essentially comprises the following steps:

[0069] In a first step, a bulk layer 22 containing at least one through hole 24 is provided.

[0070] In a second step, a substrate layer 26 is provided and an adhesive 30 is formed or applied to its lamination surface 28 .

[0071] In a third step, the bulk layer 22 and the substrate layer 26 are positioned such that the adhesive 30 faces the laminating surface 32 of the bulk layer 22 and such that the substrate layer 26 is positioned in front of at least one through hole 24 .

[0072] It should be understood that the three steps may be performed in any order, so long as at the end of the steps the adhesive 30 is facing the lamination surface 32 of the bulk layer 22 and the substrate layer 26 is disposed in front of the at least one through hole 24. These three steps may be performed before the respective components are introduced into the lamination cavity 40 of the lamination unit 38 or before they are introduced into the interior of the lamination unit 38. The bulk layer 22 and substrate layer 26 may be introduced into the lamination unit 38 without contacting each other or with them already in contact with each other.

[0073] More essentially, in a fourth step, the bulk layer 22 and the substrate layer 26 are joined in a lamination cavity 40 as shown in Fig. 3. The bulk layer 22 and the substrate layer 26 preferably enter the lamination unit 38 in the machine direction 20 of the apparatus 36 of the invention, but this is not essential and merely serves to better illustrate the preferred embodiment of carrying out the method of the invention. The machine direction 20 of the apparatus 36 of the invention may coincide with the machine direction 20 of the packaging container making machine 14 as shown in Fig. 1, and the same reference numbers are used to simplify the present specification. The packaging container making machine 14 may be combined with the apparatus 36 of the invention.

[0074] More essentially, the lamination unit 38 comprises a first lamination means 42 and a second lamination means 44. The substrate layer 26 and the bulk layer 22 are disposed between the first lamination means 42 and the second lamination means 44. At least one non-adhesive lamination means 46 is provided between the second lamination means 44 and the bulk layer 22. With the described arrangement, the respective components are kinematically arranged in the following order: second lamination means 44, at least one non-adhesive lamination means 46, bulk layer 22, adhesive 30 or adhesive lamination surface 28 of substrate layer 26, substrate layer 26, and first lamination means 42. The first lamination means 42 and the second lamination means 44 generate a lamination pressure 48 between them, thereby bonding the bulk layer 22 and the substrate layer 26. The lamination pressure 48 may cause the adhesive 30 (or in some embodiments the material of the laminate surface 28) to build up within the through-hole 24. However, the at least one non-adhesive lamination means 46 ensures that the through-hole 24 is adequately sealed with the surface 34 of the bulk layer 22 opposite the laminate surface 32 thereof.

[0075] According to the present invention, the position 50 of the at least one non-adhesive laminating means 46 is controlled such that the at least one through hole 24 is covered by the at least one non-adhesive laminating means 46 at least as long as laminating pressure 48 is applied to the at least one valley hole 24. Alternatively, or in combination, the position of the bulk layer 22 is controlled such that the at least one through hole 24 is covered by the at least one non-adhesive laminating means 46 at least as long as laminating pressure 48 is applied to the at least one through hole 24.

[0076] It is therefore ensured that the through-hole 24 will always be properly sealed to the side 34 of the bulk layer 22 even if the different components involved in the method of the present invention change their relative positions.

[0077] In the following, some optional but preferred embodiments of the inventive method and the inventive apparatus 36 are described in more detail. First, it is noted that the bulk layer 22 and the substrate layer 26 are generally joined by a lamination process, which may be embodied in various ways, for example, a dry lamination process or a wet lamination process. Preferably, the joining may be performed by a dispersion and / or wet lamination process.

[0078] In the illustrated embodiment, the method of the present invention is carried out as a continuous or discontinuous flow process in the machine direction 20, and the position 50 of the non-adhesive laminating means 46 is controlled at least in a direction 52 transverse to the machine direction 20. The relative position of the non-adhesive laminating means 46 and the bulk layer 22 may be controlled along the machine direction 20, for example, by controlling the speed 54 of the non-adhesive laminating means 46, and may also be controlled in a perpendicular direction, for example, parallel to the laminating pressure 48 as shown in FIG.

[0079] Preferably, the first laminating means 42 and the second laminating means 44 each include a laminating roller 56. The laminating roller 56 may preferably rotate 58 to transport the laminated packaging material 16 in the machine direction 20. The laminating roller 56 is preferably capable of transmitting a laminating pressure 48 and may be driven or heat controlled according to the requirements of the process.

[0080] The position 50 of the non-adhesive laminating means 46 may be controlled at least in a direction 52 parallel to the axis of rotation 60 of the laminating roller 56. Similarly, correct positioning may be achieved by shifting the position of the bulk layer 22.

[0081] Preferably, one of the lamination rollers 56 may be a nip roller 62 and the other lamination roller 56 may be a chilled roller 64 .

[0082] The non-adhesive laminating means 46 preferably comprises a non-adhesive belt 66 , more preferably made from Teflon, which is guided over a laminating roller 56 formed by the second laminating means 44 .

[0083] In the following, according to view AA defined by section line A in FIG. 3, reference is made further to FIG. 4, in which a preferred embodiment of the inventive method and of the inventive device 36 are shown.

[0084] In this view AA, the laminate cavity 40 can be seen from below, i.e., in a view directed toward the inside of the partially cut bulk layer 22 and toward the inside of the face 34 of the bulk layer 22 opposite the laminate face 32.

[0085] As can be seen in FIG. 4, the bulk layer 22 preferably includes a plurality of through holes 24, only some of which are indicated by reference numeral 24 in FIG. 4 for the sake of clarity.

[0086] More preferably, a plurality of non-adhesive laminating means 46 are used, each configured by the apparatus 36 of the present invention. All of said non-adhesive laminating means 46 are preferably kinematically positioned between the second laminating means 44 and the bulk layer 22, in accordance with the above description.

[0087] The position 50 of each non-adhesive laminating means 46 is preferably controlled such that each non-adhesive laminating means 46 covers a through-hole 24 at its respective position 50 at least as long as laminating pressure 48 is applied to the respective through-hole 24. Alternatively, or in combination, the position of the bulk layer 22 is controlled. It will be apparent that the position 50 of each non-adhesive laminating means 46 is preferably controlled independently, since different through-holes 24 are not necessarily exposed to laminating pressure 48 at the same time.

[0088] As mentioned above, the non-adhesive laminating means 46 preferably comprises a belt 66, which is preferably guided over the laminating roller 56 of the second laminating means 44. The belt 66 may also be guided or driven by one or more additional rollers 68. There are preferably eight belts 66 arranged adjacent to each other along the rotation axis 60 of the laminating roller 56, some of which are indicated and referenced by reference numbers for clarity of illustration. This may equally apply to other features which are repeated by the device 36 and are therefore only shown exemplarily in the figures.

[0089] Preferably, each of the eight belts 66 is movable within a range of 30 cm along the axis of rotation 60. Preferably, the two outermost belts 67 feature a greater width than the other belts 66 located between them, which means that the intermediate belts are each narrower than the end belts 67.

[0090] Preferably, the position 50 of each belt 66 in a direction parallel to the axis of rotation 60 of the laminating roller 56 is controlled by an actuating guide member 70 exerting a positioning force 72 on the belt 66 in that direction. This is shown in FIG. 4 and exemplarily in FIG. 5 for the lower right belt 66. Preferably, the actuating guide member 70 may comprise at least one or more guide rollers 68 carried on an individual support 69 for each of the belts 66. Preferably, this support 69, and thus the actuating guide member 70, may comprise a dedicated motor 71 driven in the direction of the positioning force 72 and / or transversely to the direction of the positioning force 72. All the guide members 70 may be driven individually in the direction of the positioning force 72 on a single slide or track 73, as exemplarily shown in FIG. 4.

[0091] The non-adhesive laminating means 46 is cleaned before and / or after contacting the through-holes 24, preferably by a cleaning device 74 (see FIG. 6).

[0092] Preferably, the cleaning device 74 is located at a location where the non-adhesive laminating means 46, such as the belt 66, has passed the first laminating means 42 and the second laminating means 44. In one embodiment, the cleaning device 74 is located after the nip rollers 62 where the belt 66 exits the nip defined by the nip rollers 62.

[0093] The cleaning device 74 may be integrated with the actuation guide member 70, with other suitable components of the apparatus 36, or may be provided as a separate unit. An exemplary such cleaning device 74 embodied as a separate unit is illustrated in FIG. 6 and described below.

[0094] 4, a sensor 76 may be provided to greatly improve control of the relative position between the non-adhesive laminating means 46 and the bulk layer 22. The sensor 76 may detect the position 78 of the through-hole 24 on the bulk layer 22, which position 78 is exemplarily shown in the top left of FIG. 4. The position 50 of the non-adhesive laminating means 46 is controlled based on the detected position 78 of the through-hole 24. Correct alignment may also be achieved by shifting the position of the bulk layer 22 relative to the non-adhesive laminating means 46.

[0095] It should be understood that after joining the bulk layer 22 and the substrate layer 26, the laminated packaging material 16 may be directed through one or more subsequent rollers (not shown) equipped with non-adhesive laminating means 46 to cover the through holes 24 as long as the subsequent rollers are in contact with the through holes 24. The subsequent rollers and the respective non-adhesive laminating means 46 may comprise one or more features described in this disclosure and may, but need not, enable a laminating function. For example, the subsequent rollers may serve the purpose of cooling, storing, or transporting the laminated packaging material.

[0096] Figure 5 shows an alternative embodiment of the device 36 shown in Figure 4, in particular with regard to a different design of the slides 73, 75. Thus, in Figure 5, only the part of the device 36 featuring the guide member 70 is shown, the upper part of the device being omitted in the illustration.

[0097] As shown, there may be multiple slides or tracks 73, 75. Each slide 75 may carry a group of guide members 70 and belts 66. It is also possible, as illustratively shown with slide 73, that there are multiple slides or tracks 73, 75, each carrying one guide member 70 and belt 66, respectively.

[0098] 6, one embodiment of a cleaning device 74 provided as a separate unit is shown. An exemplary belt 66 is shown in cross section as the non-adhesive laminating means 46 has just passed the nip rollers 62. As shown, in this situation, residual adhesive 30 may be present on the belt 66. To remove residual adhesive 30, the cleaning device 74 may have a scraper 80 or similar structure to scrape off excess adhesive 30 that may remain on the belt 66.

[0099] There may be a collection vessel 82 for collecting excess adhesive 30, particularly scraped off adhesive 30. Additionally, the belt 66 may be exposed to, for example, immersed in, a cleaning bath 84. The cleaning bath 84 preferably comprises water and alcohol. Most preferably, the cleaning bath 84 is applied after the scraper 80 has been used.

[0100] After the washing bath 84, the belt 66 is dried, preferably accomplished by a suitable heat treatment means 86. As shown, residual liquid 88 is removed before the belt 66 is returned to the lamination process as indicated by the direction of travel 90. On that basis, it is particularly preferred to combine the washing device 74 with a wet lamination process.

[0101] In general, the cleaning device 74 may be embodied in a variety of ways, so long as it ensures that impurities or unavoidable residues of the adhesive material 30 applied to the non-adhesive laminating means 46 are removed before the non-adhesive laminating means 46 is again brought into contact with the bulk layer 22 and the second laminating means 44.

[0102] From the foregoing description, while various embodiments of the present invention have been described and illustrated, the invention is not limited thereto and may be embodied in other ways within the scope of the subject matter defined in the following claims.

Claims

1. A method for manufacturing a laminated packaging material (16) capable of forming a packaging container (10) for packaging a liquid food product (12), comprising the steps of: providing a bulk layer (22) of paper or paperboard or other cellulosic material having at least one through hole (24); providing a substrate layer (26) and an adhesive (30) formed or applied to a laminating surface (28) of the substrate layer; positioning the bulk layer (22) and the substrate layer (26) so that the adhesive (30) faces the laminating surface (32) of the bulk layer (22) and so that the substrate layer (26) is positioned in front of the at least one through hole (24); a laminating unit (38) for joining the bulk layer (22) and the substrate layer (26), wherein a first laminating means (42), the substrate layer (26), the bulk layer (22), and a second laminating means (44) are kinematically arranged in the listed order, a laminating pressure (48) is generated between the first and second laminating means (42; 44), and at least one non-adhesive laminating means (46) is kinematically arranged between the second laminating means (44) and the bulk layer (22); the position of the bulk layer (22) and / or the position (50) of the at least one non-adhesive laminating means (46) is controlled so that the at least one through-hole (24) is covered by the at least one non-adhesive laminating means (46) at least as long as the laminating pressure (48) is applied to the at least one through-hole (24); method.

2. the bulk layer (22) comprises a plurality of through holes (24), and a plurality of non-adhesive laminating means (46) are kinematically disposed between the second laminating means (44) and the bulk layer (22); the position of the bulk layer (22) and / or the position (50) of each non-adhesive laminating means (46) is controlled so that each non-adhesive laminating means (46) covers the through-hole (24) at its respective position (50) at least as long as the laminating pressure (48) is applied to each through-hole (24); The method of claim 1.

3. Each of the first and second laminating means (42; 44) comprises a laminating roller (56) for transmitting the laminating pressure (48), and the position (50) of the bulk layer (22) and / or the non-adhesive laminating means (46) is controlled at least in a direction parallel to the rotation axis (60) of the laminating roller (56). The method of claim 1.

4. The non-adhesive laminating means (46) comprises a non-adhesive belt (66) guided over the laminating roller (56) formed by the second laminating means (44). The method of claim 3.

5. The position (50) of the belt (66) in a direction parallel to the rotation axis (60) of the laminating roller (56) is controlled by an actuating guide member (70) that applies a positioning force (72) to the belt (66) in a direction parallel to the rotation axis (60) of the laminating roller (56). The method of claim 4.

6. a continuous or discontinuous flow process carried out in the machine direction (20), wherein the position of said bulk layer (22) and / or the position of said non-adhesive laminating means (50) is controlled at least in the direction (52) transverse to said machine direction (20); The method of claim 1.

7. After joining the bulk layer (22) and the substrate layer (26), the laminated packaging material (16) is guided through at least one subsequent roller provided with a non-adhesive laminating means (46) that covers the through holes (24) as long as the subsequent roller is in contact with the through holes (24). The method of claim 1.

8. A sensor (76) detects the position (78) of the through-hole (24) on the bulk layer (22), and the position (50) of the bulk layer (22) and / or the non-adhesive laminating means (46) is controlled based on the detected position (78) of the through-hole (24). The method of claim 1.

9. The non-adhesive laminating means (46) is cleaned by a cleaning device (74) before and / or after contacting the through-hole (24). The method of claim 1.

10. A laminate packaging material (16) produced by the method of claim 1.

11. A packaging container (10) made from the laminate packaging material (16) of claim 10.

12. 1. An apparatus (36) for producing a laminated packaging material (16) for forming a packaging container (10) for packaging a liquid food product (12), comprising: The apparatus (36) comprises a laminating unit (38) configured to receive a bulk layer (22) having at least one through hole (24) and a substrate layer (26) having an adhesive (30) formed by or applied to a laminating surface (28); The laminating unit (38) comprises a first laminating means and a second laminating means configured to form a laminating cavity therebetween and to apply laminating pressure to the bulk layer and the substrate layer when the layer (22; 26) is introduced into the laminating cavity (40), and the laminating unit (38) further comprises at least one non-adhesive laminating means (46) kinematically disposed between the second laminating means (44) and the bulk layer (22) when the laminating unit (38) is introduced into the laminating cavity (40); the position of the bulk layer (22) and / or the position (50) of the at least one non-adhesive laminating means (46) is controllable such that the at least one through-hole (24) is covered by the at least one non-adhesive laminating means (46) at least as long as a laminating pressure (48) is applied to the at least one through-hole (24); Apparatus (36).

13. adapted and configurable to perform the method of claim 1, 13. The apparatus (36) of claim 12.

14. a sensor (76) for detecting a position (78) of the through-hole (24) on the bulk layer (22); Based on the detected positions (78) of the through holes (24), the position (50) of the bulk layer (22) and / or the non-adhesive laminating means (46) can be controlled.

13. The apparatus (36) of claim 12.

15. The laminated packaging material (16) is produced in a continuous or discontinuous flow process carried out in a machine direction (20), and the position of the bulk layer (22) and / or the position of the non-adhesive laminating means (46) (50) are controllable at least in a direction (52) transverse to the machine direction (20).

13. The apparatus (36) of claim 12.

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