Method

Abstract

Manufacture of a fibre-based packaging container comprises the steps of providing a quadrilateral blank comprising an inner and outer wall surface, the inner wall surface comprising a liquid impermeab

Description

The present invention relates to improved methods of producing paperboard containers, such as a disposable cups. More specifically, the present invention relates to methods of producing paperboard containers comprising recyclable and / or compostable coatings and adhesives, preferably using conventional container manufacturing machines. BACKGROUND OF THE INVENTION Historically, disposable beverage cups and drinking containers typically were formed of fibrebased board comprising a layer of polyethylene or other polymeric materials to provide a liquid barrier. However, more recently, the use of polyethylene and certain other polymers has been banned in many countries as the environmental impact of polymeric waste is of serious concern. Therefore, there has been a significant move in the disposable packaging industry towards manufacturing containers using ‘next generation’ alternative, more environmentally friendly materials. During the manufacture of drinking containers, a thin liquid barrier layer is applied to a surface of the fibre-based material before the coated material is spooled into reels. The liquid barrier coating may be organic (for example, polymers or monomers other than those identified as being of environmental concern e.g. polyethylene) or inorganic (for example, comprising mineral materials such as silica) or a mix of both. The reels are printed to apply any required outer decoration and are then carefully machine cut into accurately measured cup sidewall blanks. The blanks are inserted into cup-forming machines that wrap the sidewall blanks into a cup shape and seal them. The cup bottom is subsequently added and heat-sealed in place. The seams of the cups are sealed to make the cups liquid proof. In some cases, folding or crimping of the seam between the wall and base takes place to further strengthen the form of the cup. The portions of the sidewall blanks and cup bases which are sealed to themselves or each other may comprise a sealable lacquer coating to permit a reliable seal to be formed. Such processes are based on and largely replicate processes for manufacturing cups having polyethylene barrier coatings applied thereto. However, many of the more environmentally friendly liquid barrier materials have different properties to polyethylene meaning that machines configured for use with polyethylene coated substrates may perform sub-optimally or produce sub-optimal containers when substrates comprising different liquid barrier materials are used, for example cracking of the coating when the coated substrate is folded or curled, thus reducing liquid barrier function. Additionally, despite their environmental drawbacks, polyethylene-based liquid barriers function exceptionally well. While the ‘next generation’ environmentally friendly liquid barrier coatings do function effectively, the inventors have identified that liquid barrier function may not be sufficiently acceptable if the same techniques for applying polyethylene-based layers to substrates and / or forming containers from substrates comprising polyethylene-based liquid barrier layers are simply deployed for applying ‘next generation’ coatings or forming cups from substrates comprising those coatings. There is therefore a need for optimisation of processes used conventionally to form containers from polyethylene-coated substrates to permit their effective use with substrates coated with environmentally friendly, ‘next generation’ liquid barrier coatings. SUMMARY OF THE INVENTION The present invention seeks to address the problems of the prior art. Aspects of the present invention are set out in the attached claims. According to an aspect of the present invention, there is provided a method of manufacture of a fibre-based packaging container, wherein the method comprises the steps of: a. providing a quadrilateral blank comprising an inner wall surface and an outer wall surface opposing the inner wall surface, the inner wall surface comprising a liquid impermeable layer, the quadrilateral blank further comprising a first edge and second edge opposing the first edge, wherein the first and second edges are linear, and a third edge and a fourth edge opposing the third edge, each of the third and fourth edges defining an arc, wherein a first edge sealing portion extends partially across the inner wall surface from the first edge and a second edge sealing portion extends partially across the outer wall surface from the second edge, and wherein a base sealing portion extends partially across the inner wall surface adjacent the third edge; b. providing a circular base component having an outer edge, an inner base surface and an outer base surface opposing the inner base surface, the inner base surface having a liquid impermeable layer and comprising a wall sealing portion; c. flexing the quadrilateral blank to bring the first and second edges into overlapped engagement with one another, and sealing them to one another to form a tubular wall component with a wall seam, the tubular wall component having an interior, an exterior, an upper end and a lower end at which the base sealing portion is located; d. folding the circular base component at a fold line around the whole of the circular base component to create a circumferentially folded edge extending at 80 to 100 degrees from the rest of the circular base component wherein the circumferentially folded edge comprises the wall sealing portion, and the circumferentially folded edge and the outer base surface define a base interior; e. sealing the wall sealing portion and the base sealing portion to one another to form a base seam between the tubular wall component and the circular base component; wherein 1) the process further comprises the step of rolling the fourth edqe of the quadrilateral blank or the upper edge of the tubular wall component to form a rolled rim and applying a second liquid impermeable layer to the rolled rim, 2) the process further comprises the step of applying a further liquid impermeable layer to the interior of the tubular wall component and I or the inner base surface, 3) one or more of the second, third or fourth edges of the quadrilateral blank comprise a liquid impermeable layer and / or a sealable lacquer coating and I or 4) a portion of the inner wall surface and I or the outer wall surface extending partially along that surface from the fourth edge of the quadrilateral blank or the upper edge of the tubular wall component comprises an additional layer of liquid impermeable barrier material and / or sealable lacquer. Those skilled in the art will be familiar with apparatus used to produce fibre-based packaging containers and will recognise that steps a. to e. as detailed above are typically performed using such apparatus. However, the inventors have identified difficulties when utilising such apparatus to form containers from blanks and bases provided with liquid impermeable layers having a low degree of elasticity (or at least a lower degree of elasticity than polyethylene). The process optimisations of the present invention advantageously permit conventional container-forming apparatus, configured for use with substrates coated with polyethylene, to be modified in a straightforward manner to permit their use with substrates provided with a broader range of liquid impermeable layer materials. For the avoidance of doubt, the present invention is not limited to processes in which steps a. to e. are conducted in the order in which they are presented herein. For example, step d. could be performed prior to or simultaneously with step c. Additionally or alternatively, step c. could be performed prior to or simultaneously with step b. In one embodiment, the process further comprises the step of rolling the fourth edqe of the quadrilateral blank or the upper edge of the tubular wall component to form a rolled rim and applying a second liquid impermeable layer to the rolled rim. Those skilled in the art will be familiar with apparatus and techniques for rolling an edge of a container to form a rolled rim. However, the inventors have identified that when wall blanks comprising certain liquid impermeable layer materials on their inner surface, for example, liquid impermeable layer materials having a low modulus of elasticity, the process of rolling an edge of the container can cause cracks to form in the liquid impermeable layer. Advantageously, it has been found that this issue can be resolved through the application of a second liquid impermeable layer to the rolled rim. The skilled artisan will be familiar with techniques for forming rolled rims in containers. Typically, this step is carried out in a rim forming station and as part of the process a lubricant such as paraffin oil is applied to facilitate rim curling I forming. The inventors have advantageously found, however, that by applying the liquid impermeable barrier instead of the lubricant, the liquid impermeable barrier material functions effectively as a lubricant but, once dried, functions as a barrier to provide additional resistance to moisture penetration. Thus, in embodiments of the invention, lubricant (other than the liquid impermeable barrier material) may not be applied during the step of rolling the fourth edge of the quadrilateral blank or the upper edge of the tubular wall component to form a rolled rim. In certain embodiments, liquid impermeable barrier material and I or sealable lacquer may be applied to a portion of the inner wall surface or the outer wall surface extending from the fourth edge of the quadrilateral blank or the upper edge of the tubular wall component prior to or during the step of rolling that edge to form a rolled rim. This may be in addition to or instead of the application of a second liquid impermeable layer to the rolled rim. Thus, in embodiments of the invention (whether part 1), part 2) and I or part 3) of the process of the invention are performed or not), a portion of the inner wall surface or the outer wall surface extending partially along that surface from the fourth edge of the quadrilateral blank I the upper edge of the tubular wall component may comprise a an additional layer of liquid impermeable barrier material and I or sealable lacquer. In some embodiments, the portion comprises a sealable lacquer layer and an additional layer of liquid impermeable barrier material applied thereupon. This portion may extend from some or substantially all of the fourth edge. In embodiments, this portion extends from the entirety of the fourth edge. According to a further aspect of the invention, there is provided a quadrilateral blank comprising an inner wall surface and an outer wall surface opposing the inner wall surface, the inner wall surface comprising a liquid impermeable layer, the quadrilateral blank further comprising a first edge and second edge opposing the first edge, wherein the first and second edges are linear, and a third edge and a fourth edge opposing the third edge, each of the third and fourth edges defining an arc, wherein a first edge sealing portion extends partially across the inner wall surface from the first edge and a second edge sealing portion extends partially across the outer wall surface from the second edge, wherein a portion of the inner wall surface and I or the outer wall surface extending partially along that surface from the fourth edge of the quadrilateral blank comprises an additional layer of liquid impermeable barrier material and I or sealable lacquer. The quadrilateral blank of this aspect of the invention may comprise any of the features disclosed herein as being comprised in quadrilateral blanks of other aspects of the invention. The second liquid impermeable layer may comprise the same barrier material as the liquid impermeable layer applied to the inner wall surface of the quadrilateral wall blank and I or the inner base surface of the base. In alternative embodiments, the second liquid impermeable layer may comprise a different barrier material as the liquid impermeable layer applied to the inner wall surface of the quadrilateral wall blank and I or the inner base surface of the base. The second liquid impermeable layer may comprise any of the liquid impermeable barrier materials discussed herein. As will be appreciated, the rolled rim may have a circular shape in cross section. In embodiments, the second liquid impermeable layer may be applied to the upper part of the rolled rim, i.e. the uppermost part of the tubular wall component. In such embodiments, the second liquid impermeable layer may be applied via an applicator comprising a permeable region in fluid communication with a supply of the second liquid impermeable layer material, and the permeable region is contacted with the upper part of the rolled rim. In such embodiments, the permeable region of the applicator may be sized to correspond to the shape of the rolled rim. Additionally or alternatively, the permeable region of the applicator may be shaped to correspond to the shape of the rolled rim. For example, if the rolled rim of the container is circular, the permeable region of the applicator may also be circular. The permeable region of the applicator may also be resilient and I or elastic. In embodiments, the permeable region of the applicator may be formed from a fabric material (e.g. it may comprise a woven fabric material such as felt or a non-woven fabric material), a natural or synthetic sponge or a rubber or rubber type material which is porous or provided with holes therein. The applicator may be formed of any material deemed suitable by one skilled in the art. In embodiments, the applicator, or at least the portions of it which are in fluid communication with the second liquid impermeable barrier material are not metallic. In some embodiments, the second liquid impermeable layer may be applied to the entirety of the rolled rim. The second liquid impermeable layer may be applied using a spray. The step of rolling the fourth edge to form a rolled rim and I or applying the second liquid impermeable layer to the rolled rim may be performed after step c. but before step e. of the process of the invention. Alternatively, the step of rolling the fourth edge to form a rolled rim and I or applying the second liquid impermeable layer to the rolled rim may be performed after step e. of the process of the invention. In some embodiments, the step of rolling the fourth edge to form a rolled rim may be performed after step c. but before step e., and the step of applying the second liquid impermeable layer to the rolled rim may be performed after step e. of the process of the invention. According to a further aspect of the present invention, there is provided a cup formed from a paperboard substrate comprising, on its interior surface, a mineral-based liquid impermeable layer and a rolled rim at its upper end, the rolled rim comprising a plurality of mineral-based liquid barrier layers. Such a cup may be obtainable from the process of the present invention. According to a further aspect of the present invention, there is an applicator for applying a liquid impermeable barrier to a rolled rim on a container, e.g. a papercup, wherein the applicator comprises a permeable region in fluid communication with a supply of liquid impermeable barrier material. The applicator may additionally comprise any of the other features of the applicator discussed herein. According to a further aspect of the invention, there is provided a container forming machine comprising an applicator as discussed herein. The container forming machine may additionally comprise one or more of the following stations: a wall seam forming station, a heating station, a base folding station and a base seam forming station. In some embodiments, the process comprises the step of applying a further liquid impermeable layer to the interior of the tubular wall component and I or the inner base surface. This step may be performed after step c. but before step e. of the process or alternatively may be performed after step e. of the process of the invention. The further liquid impermeable layer may comprise the same barrier material as the liquid impermeable layer applied to the inner wall surface of the quadrilateral wall blank and I or the inner base surface of the base. In alternative embodiments, the further liquid impermeable layer may comprise a different barrier material as the liquid impermeable layer applied to the inner wall surface of the quadrilateral wall blank and / or the inner base surface of the base. The further liquid impermeable layer may comprise any of the liquid impermeable barrier materials discussed herein. The further liquid impermeable layer may be applied to the interior of the tubular wall component and I or the inner base surface using any technique or apparatus known to the skilled person. In some embodiments, the further liquid impermeable layer may be applied to the interior of the tubular wall component and / or the inner base surface using a spray. In embodiments of the invention in which parts 1) and 2) of the process are performed, and the second liquid impermeable barrier is applied to the rolled rim via an applicator, the applicator may additionally be provided with a spray nozzle to conveniently permit the application of the second liquid impermeable layer and the further liquid impermeable layer in a single operation. Thus, in embodiments of the invention, parts 1) and 2) may be performed simultaneously. In embodiments of the process of the invention, following the application of the further liquid impermeable layer to the interior of the tubular wall component and I or the inner base surface, where the further liquid impermeable layer is applied in the form of a liquid, it may be allowed to dry in ambient air, or it may be dried with hot air. According to a further aspect of the present invention, there is an applicator for applying a liquid impermeable barrier to a rolled rim on a container, e.g. a papercup, wherein the applicator comprises a permeable region in fluid communication with a supply of liquid impermeable barrier material and a spray nozzle in fluid communication with a supply of liquid impermeable barrier material. The applicator may additionally comprise any of the other features of the applicator discussed herein. According to a further aspect of the invention, there is provided a container forming machine comprising an applicator as discussed herein. The container forming machine may additionally comprise one or more of the following stations: a wall seam forming station, a heating station, a base folding station and a base seam forming station. According to a further aspect of the present invention, there is provided a cup formed from a paperboard substrate comprising, on its interior surface, a plurality of mineral-based liquid impermeable layers. Such a cup may be obtainable from the process of the present invention. In some embodiments of the invention, one or more of the second, third or fourth edges of the quadrilateral blank comprise a liquid impermeable layer and / or a sealable lacquer coating. In certain embodiments, one or both of the base sealing portion and the wall sealing portion comprise a sealable lacquer coating and the sealable lacquer coating is present within the base seam. Additionally or alternatively, one or both of the first and second edge sealing portions may comprise a sealable lacquer and the sealable lacquer is present within the wall seam. As those skilled in the art will recognise, in conventional container forming processes, wall blanks are typically formed by being cut from a web of substrate, e.g. paperboard, which comprises a liquid impermeable barrier, typically one comprising polyethylene. As a result of the cutting action, the edge of the wall blank does not comprise a liquid impermeable barrier. While the absence of liquid impermeable barrier material on the cut edge of the wall blanks was not previously identified as being problematic, the inventors have identified that, particularly when ‘next generation’ environmentally friendly liquid impermeable barrier materials are used, there is the possibility for liquid contained within the container to wick into the wall via the edge which can result in failure of the cup. By providing one or more of the edges in question with a liquid impermeable layer and / or a sealable lacquer coating, this issue can be prevented. In some embodiments, the second edge is provided with a liquid impermeable layer and I or a sealable lacquer coating. The entirety of the second edge may be provided with a liquid impermeable layer and / or a sealable lacquer coating. Alternatively, a part of the second edge extending from the third edge may be provided with a liquid impermeable layer and / or a sealable lacquer coating. Additionally or alternatively, a part of the second edge extending from the fourth edge may be provided with a liquid impermeable layer and / or a sealable lacquer coating. In some embodiments, the third edge is provided with a liquid impermeable layer and / or a sealable lacquer coating. The entirety of the third edge may be provided with a liquid imper meable layer and / or a sealable lacquer coating. Alternatively, a part of the third edge extending from the second edge may be provided with a liquid impermeable layer and / or a sealable lacquer coating. In some embodiments, the fourth edge is provided with a liquid impermeable layer and / or a sealable lacquer coating. The entirety of the fourth edge may be provided with a liquid impermeable layer and / or a sealable lacquer coating. Alternatively, a part of the fourth edge extending from the second edge may be provided with a liquid impermeable layer and / or a sealable lacquer coating. In certain embodiments, a part of the second edge extending from the third edge and a part of the third edge extending from the second edge may be provided with a liquid impermeable layer and / or a sealable lacquer coating. In some embodiments, a part of the second edge extending from the fourth edge and a part of the fourth edge extending from the second edge may be provided with a liquid impermeable layer and / or a sealable lacquer coating. According to a further aspect of the invention, there is provided a quadrilateral blank comprising an inner wall surface and an outer wall surface opposing the inner wall surface, the inner wall surface comprising a liquid impermeable layer, the quadrilateral blank further comprising a first edge and second edge opposing the first edge, wherein the first and second edges are linear, and a third edge and a fourth edge opposing the third edge, each of the third and fourth edges defining an arc, wherein a first edge sealing portion extends partially across the inner wall surface from the first edge and a second edge sealing portion extends partially across the outer wall surface from the second edge, wherein one or more of the second, third or fourth edges of the quadrilateral blank comprise a liquid impermeable layer and / or a sealable lacquer coating. The quadrilateral blank of this aspect of the invention may comprise any of the features disclosed herein as being comprised in quadrilateral blanks of other aspects of the invention. Where reference is made herein to a part of an edge (e.g. the second, third or fourth edge of the quadrilateral blank) extending from another edge, the part may extend by about 80% or less, about 70% or less, about 60% or less, about 50% or less, about 40% or less, about 30% or less or about 20% or less along the length of the edge in question. The liquid impermeable layer and / or sealable lacquer coating applied to the second, third or fourth edge of the quadrilateral wall blank may be any of the liquid impermeable layer materials and I or sealable lacquer coating materials discussed herein. The liquid impermeable layer applied to the second, third or fourth edge of the quadrilateral wall blank may be the same as or different to the liquid impermeable layer comprised on the inner wall surface of the quadrilateral blank and I or the inner base surface of the base. The sealable lacquer coating applied to the second, third or fourth edge of the quadrilateral wall blank may be the same as or different to the sealable lacquer coating comprised on the base sealing portion and I or the wall sealing portion. In embodiments of the invention, the process comprises the step of applying a liquid impermeable layer and / or a sealable lacquer coating to one or more of the second, third or fourth edges of the quadrilateral blank. In certain embodiments, this step is performed prior to step c. of the process of the invention. Alternatively, the step could be performed after step c. in which the quadrilateral blank is formed into the tubular wall component. The step of applying the liquid impermeable layer and / or a sealable lacquer coating to one or more of the second, third or fourth edges of the quadrilateral blank may be performed by techniques known to those skilled in the art, e.g. by brushing or spraying. In some embodiments, the liquid impermeable layer and / or a sealable lacquer coating may be applied to one or more of the second, third or fourth edges of a plurality of quadrilateral blanks simultaneously. Steps a. to e. of the process of the invention may be carried out by the same container-forming machine. Alternatively, certain of steps a. to e. may be carried out on a first machine and the remaining steps may be carried out on one or more different machines. For example, the quadrilateral blank provided in step a. may be formed by cutting the blank out of a web and then optionally applying a liquid impermeable layer and / or a sealable lacquer coating to one or more of the second, third or fourth edges of the quadrilateral blank. The circular base component may also be provided in step b. by cutting the circular base component out of a web. The machine used to cut the quadrilateral blank out of the web may be the same or different to the machine used to cut the circular base component out of the web. Further, steps c. to e. may be carried out using a conventional container forming machine, which may be the same or different machine as that or those used to cut the quadrilateral blank and I or the circular base component out of their respective webs. Where multiple steps are performed using the same machine, these may be performed at different stations within the same machine. As the process progresses, the components of the container may be moved by the machine from one station to another, e.g. by a conveyor such as a rotary conveyor, conveyor belt or the like. In step a., a quadrilateral blank is provided comprising an inner wall surface and an outer wall surface opposing the inner wall surface, the inner wall surface comprising a liquid impermeable layer. The quadrilateral blank further comprises a first edge and second edge opposing the first edge, wherein the first and second edges are linear, and a third edge and a fourth edge opposing the third edge, each of the third and fourth edges defining an arc. The quadrilateral blank also comprises a first edge sealing portion extending partially across the inner wall surface from the first edge and a second edge sealing portion extending partially across the outer wall surface from the second edge. A base sealing portion is also present which extends partially across the inner wall surface adjacent the third edge. In embodiments, the first and second edges of the quadrilateral wall blank are equal in length to one another. As those skilled in the art will recognise, the use of quadrilateral wall blanks to produce containers is well known, including those in which notches or other portions are cut out in order to facilitate manufacture of the container. For the avoidance of doubt, where reference is made herein to the first and second edges of the quadrilateral wall blank being equal in length to one another, the length of the edge in question should be measured not taking into account the effect of such notches or other cut out portions on the length of the edge, i.e. as if no notches or cut out portions were present. One or both of the first and second edge sealing portions of the quadrilateral blank may comprise a sealable lacquer coating. Additionally or alternatively, the base sealing portion may comprise a sealable lacquer coating. The quadrilateral blank may comprise a liquid impermeable layer on the entirety or at least substantially all of the entirety of the inner wall surface. In embodiments, the first edge sealing portion may extend along the inner wall surface of the quadrilateral blank from the first edge by a distance of about 5mm to about 30mm, about 7mm to about 20mm, or about 10mm to about 15mm. In certain embodiments, the second edge sealing portion may extend along the outer wall surface of the quadrilateral blank from the second edge by a distance of about 5mm to about 30mm, about 7mm to about 20mm, or about 10mm to about 15mm. In some embodiments, the base sealing portion may extend along the inner wall surface of the quadrilateral blank from the third edge by a distance of about 5mm to about 30mm, about 7mm to about 20mm, or about 10mm to about 15mm. The use of quadrilateral blanks to form the walls of containers, e.g. cups, will be familiar to the skilled person. The provision of such blanks may be achieved in processes of the invention by providing a web of fibre-based material and cutting the blank out therefrom, e.g. by diecutting. In embodiments, prior to the quadrilateral blank being cut from the web, the web may comprise the liquid impermeable layer. Alternatively, the liquid impermeable layer may be applied to the blank after being cut from the web. As discussed above, in embodiments of the invention, a liquid impermeable layer and / or a sealable lacquer coating to one or more of the second, third or fourth edges of the quadrilateral blank after the blank is cut from the web. In embodiments in which the base sealing portion and I or the first and I or the second edge sealing portion comprises a sealable lacquer coating, this may be comprised on the web before the quadrilateral blank is cut therefrom. Alternatively, the sealable lacquer coating may be applied to the blank after being cut from the web. Step a. may be carried out in a container-forming machine, e.g. at a sidewall blank cutting station in such a machine. Alternatively, step a. may be carried out using a cutting machine and the quadrilateral blanks obtained therefrom are moved to a container-forming machine which carries out some or all of steps c. to e. In some embodiments, step a. may be performed by sourcing pre-cut quadrilateral wall blanks. As noted above, a liquid impermeable layer and / or a sealable lacquer coating may be applied to one or more of the second, third or fourth edges of the quadrilateral blank. This step may be performed in the same container-forming machine as that in which step a. is carried out, or in a different machine. In step b., a circular base component is provided comprising an outer edge, an inner base surface and an outer base surface opposing the inner base surface, the inner base surface comprising a liquid impermeable layer and a wall sealing portion. The wall sealing portion may be provided with a sealable lacquer coating. The circular base component may comprise a liquid impermeable layer on the entirety or at least substantially all of the entirety of the inner base surface. The use of circular base components to form the base of containers, e.g. cups, will be familiar to the skilled person. The provision of such components may be achieved in processes of the invention by providing a web of fibre-based material and cutting the circular base component out therefrom, e.g. by die-cutting. In embodiments, prior to the circular base component being cut from the web, the web may comprise the liquid impermeable layer. Alternatively, the liquid impermeable layer may be applied to the circular base component after it is cut from the web. In embodiments in which the wall sealing portion comprises a sealable lacquer coating, this may be comprised on the web before the circular base component is cut therefrom. Alternatively, the sealable lacquer coating may be applied to the circular base component after it is cut from the web. Step b. may be carried out in a container-forming machine, e.g. at a circular base component cutting station within the machine. Alternatively, step b. may be carried out using a cutting machine and the circular base components obtained therefrom are moved to a containerforming machine which carries out some or all of steps c. to e. In some embodiments, step b. may be performed by sourcing pre-cut circular base components. Step b. may be carried out using the same or different machine than step a. Where steps a. and b. are performed using the same machine, they may be performed at different stations within that machine. In step c., a tubular wall component is formed by flexing the quadrilateral blank to bring the first and second edges into overlapped engagement with one another, and sealing them to one another to form a tubular wall component with a wall seam. The tubular wall component has an interior, an exterior, an upper end and a lower end at which the base sealing portion is located. The quadrilateral blank may be flexed around a mandrel shaped to correspond to the interior of the container. One or both of the first and second edge sealing portions of the quadrilateral blank may comprise a sealable lacquer coating. The wall seam may be formed by applying energy (e.g. mechanical, thermal and / or ultrasonic energy) to the first and second edge sealing portions to seal them together thus forming the wall seam. Step c. may be perfomed in a wall seam forming station in a container forming machine. The tubular wall component formed in step c. may then be moved (e.g. from one station in a container-forming machine to another, or from one machine to another) in order for the subsequent steps of the process of the present invention to be carried out. In step d., the circular base component is folded at a fold line extending around the whole of the base component blank to create a circumferentially folded edge extending generally perpendicularly from the rest of the circular base component. By “generally perpendicularly” it is meant that the wall sealing portion is folded about the fold line by about 80° to about 100°, about 85° to about 95°, or about 90° from the plane of the circular base component. The fold line may or may not be marked and I or visible prior to folding of the wall sealing portion. In some embodiments, the fold line may be scored or marked to facilitate reliable and repeatable positioning of the fold. Folding of the edge of the circular base component may be achieved using any suitable techniques or apparatus known to those of skill in the art. Step d. may be performed at a folding station which may be part of the same machine in which steps c. and I or e. are performed in. Alternatively, step d. may be performed in a different machine to steps c. and I or e. In some embodiments the circular base component may be positioned on a circular, planar mandrel having a smaller diameter than the circular base component (e.g. such that the circumference of the mandrel corresponds to the fold line) such that the edge of the circular base component and the wall sealing portion extend beyond the edge of the mandrel. The circular base component may then be passed through a cylindrical sleeve having a diameter greater than the diameter of the mandrel but smaller than the diameter of the circular base component (or the cylindrical sleeve may be passed over the circular base component and mandrel) which causes folding of the edge of the circular base component to form the circumferentially folded edge. Once step d. has been completed, the folded circular base component may then be moved (e.g. from the folding station to another, or from one machine to another) in order for the subsequent steps of the process of the present invention to be carried out. Prior to step e., the folded circular base component may be positioned within the interior of the tubular wall component at its lower end, e.g. such that the wall sealing portion of the circular base component and the base sealing portion of the tubular wall component are adjacent to each other, e.g. those portions are facing each other and I or abutting each other. The step of positioning the folded circular base component within the interior of the tubular wall component at its lower end may be conducted in a station within the container forming apparatus. Positioning of the circular base component within the lower end of the tubular wall component can be achieved by the circular base component being retained on the mandrel after step d. and the mandrel being moved into the base of the tubular wall component to position the folded circular base component therein. Once the folded circular base component has been moved into the interior of the tubular wall component at its lower end, sealing step e. may be performed. Alternatively, a heating step may then be performed, prior to step e. Alternatively, an additional folding step may be performed in which the base sealing portion of the tubular wall component is folded around the circumferentially folded edge region of the circular base component. In such embodiments, both the inner base surface and the outer base surface of the circular base component may comprise wall sealing portions, one or both of which may be provided with a sealable lacquer coating. In embodiments in which the outer base surface comprises a wall sealing portion comprising a sealable lacquer coating, the weight of the sealable lacquer coating provided in the wall sealing portion may be greater than the weight of the sealable lacquer coating provided in the wall sealing portion of the inner base surface. Folding of the base sealing portion of the tubular wall component around the circumferentially folded edge region of the circular base component may be achieved using means known to a person skilled in the art, e.g. a base folding station. In embodiments, the base folding station may comprise a metal plate (e.g. one having a curved circumferential shape) which is moved toward the base of the tubular wall component, forcing at least a portion of the base sealing portion into the base interior. In embodiments of the invention, the process of the invention may include the step of heating the base sealing portion and I or the wall sealing portion, e.g. using heated air which may be directed into the base interior or the interior of the lower end of tubular wall component. This heating step may be performed as part of step e. or prior to that step. In some embodiments, the heating step may be performed prior to step e. and then a further heating step may be performed as part of step e. The heating step may be performed at a heating station and the tubular wall component and I or circular base component moved to a sealing station for the performance of step e. Alternatively, the heating step and the sealing step may be performed at the same station. The heating step may be performed prior to step e. to facilitate folding of the base sealing portion and I or to prepare the container components (e.g. to enable the sealable lacquer coating to attain the activation temperature) for sealing step e. In embodiments, the base sealing portion and I or the wall sealing portion may be heated to the activation temperature of the liquid impermeable layer or sealable lacquer coating. In certain embodiments, the process of the invention may comprise multiple heating steps, e.g. one prior to step e. and one during step e. In step e., the wall sealing portion and the base sealing portion are sealed to one another to form a base seam between the tubular wall component and the circular blank. One or both of the base sealing portion of the tubular wall component and the wall sealing portion of the circular base component may comprise a sealable lacquer coating and the sealable lacquer coating is present within the base seam. During step e., the tubular wall component and I or the circular base component may be retained in position, e.g. on a mandrel. Step e. may be performed in a base sealing station. In some embodiments, the base sealing portion comprises a sealable lacquer coating. In alternative embodiments, the wall sealing portion comprises a sealable lacquer coating. In certain embodiments, both the base sealing portion and the wall sealing portion comprise a sealable lacquer coating. The base seam may be formed by applying energy (e.g. mechanical, thermal and / or ultrasonic energy) to the base sealing portion and the wall sealing portion to seal them together forming the base seam. In certain embodiments, the base seam may be formed through the application of thermal and mechanical energy. For example, thermal energy may be applied via a heating step, e.g. in the form of hot air directed into the base interior or the interior of the lower end of tubular wall component and mechanical energy may be applied using a knurling member e.g. by rotating such a member within the base interior to apply mechanical pressure to the base sealing portion and the wall sealing portion. In embodiments, a mandrel is positioned in the interior of the tubular wall component prior to and I or during step e. to retain the tubular wall component in position during the sealing step and I or positioning of the circular base component in the lower end of the tubular wall component and I or folding of the base sealing portion of the tubular wall component around the circumferentially folded edge region of the circular base component. The process of the invention may additionally comprise the step of rolling the fourth edqe of the quadrilateral blank or the upper edge of the tubular wall component, e.g. to provide a more comfortable rim for the user when drinking from the cup. This step maybe performed in a rimforming station in a machine. The step of rolling the fourth edqe of the quadrilateral blank or the upper edge of the tubular wall component is performed in part 1) of the process of the invention, but may additionally or alternatively be performed in parts 2) and I or 3) of the process of the invention. In embodiments of the invention, a portion of the inner wall surface or the outer wall surface extending partially along that surface from the fourth edge of the quadrilateral blank / the upper edge of the tubular wall component may comprise an additional layer of liquid impermeable barrier material and I or sealable lacquer. In some embodiments, the portion comprises a sealable lacquer layer and an additional layer of liquid impermeable barrier material applied thereupon. This portion may extend from some or substantially all of the fourth edge. In embodiments, this portion extends from the entirety of the fourth edge. In certain embodiments, this portion may extend along the surface of the quadrilateral blank from the fourth edge by a distance of about 5mm to about 30mm, about 7mm to about 20mm, or about 10mm to about 15mm. In certain embodiments, the first edge sealing portion contacts the base sealing portion. For example, the sealable lacquer coating may extend continuously from the first edge and the third edge of inner wall surface of the quadrilateral blank. Additionally or alternatively, the portion comprising sealable lacquer coating may extend continuously from the fourth edge, the first edge (e.g. the first edge sealing portion) and I or the third edge (e.g. the base sealing portion) of the inner wall surface of the quadrilateral blank. In some embodiments, the portion comprising sealable lacquer coating may extend continuously from the fourth edge, the first edge (e.g. the wall sealing portion) and the third edge (e.g. the base sealing portion) of the inner wall surface of the quadrilateral blank. In such embodiments, the process may further comprise applying a second liquid impermeable layer to the rolled rim. Examples of liquid impermeable layer materials and details regarding their properties will now be discussed. These exemplary materials and properties may be comprised in the liquid impermeable layer comprised on the inner wall surface, the inner base surface and I or one or more of the second, third and I or fourth edges of the quadrilateral blank, the second liquid impermeable layer applied to the rolled rim, the further liquid impermeable layer applied to the inner wall surface and I or the inner base surface, or any other liquid impermeable layer applied to any part of the container obtainable from the process of the present invention. The liquid impermeable layer c may be polymeric and I or monomeric. In certain embodiments, the polymer and I or monomer is of natural origin, i.e. the polymer and I or monomer is produced by organisms (e.g. microorganisms, plants or animals) which are optionally not genetically modified. For example, the liquid impermeable layer may comprise micro or nano cellulose, polyhydroxybutyrate (PHB), polyhydroxyalkanoate (PHA), vegetable origin protein, vegetable origin polysaccharide, fatty acid such as stearic acid or mixtures thereof. In embodiments of the invention, the liquid impermeable layer does not comprise polyethylene. Additionally or alternatively, the liquid impermeable layer may be inorganic, for example it may be a mineral liquid impermeable layer, e.g. it may comprise mineral materials such as silica, silica-based materials (e.g. ceramic), calcium carbonate, and I or kaolin. Examples of materials which may be used to provide mineral liquid impermeable layers include those listed in International Patent Publication Nos. WO2022 / 171893, WO2023 / 285499, WO2022 / 112566 and WO2021 / 019220. In preferred embodiments of the invention, the liquid impermeable layer is biodegradable. In some embodiments, the liquid impermeable layer comprises a monomer and / or a polymer which is biodegradable. The liquid impermeable layer comprised on the inner wall surface and / or the inner base surface may be metallic, e.g. it may contain metallic particles or a metallic film. However, given that the inclusion of metals will adversely affect the recyclability of the container to which it is applied as well as requiring the use of mined metals which adds to the carbon footprint of the container, the use of metals in the liquid impermeable layer is preferably avoided. Accordingly, in some embodiments, the liquid impermeable layer comprised on the inner wall surface is free of metallic film. In embodiments, the liquid impermeable layer comprised on the inner wall surface is free of metallic particles. In some embodiments, the liquid impermeable layer comprised on the inner base surface is free of metallic film. In certain embodiments, the liquid impermeable layer comprised on the inner base surface is free of metallic particles. In preferred embodiments of the invention, the liquid impermeable layer is recyclable. In some embodiments, the liquid impermeable layer comprises a monomer and / or a polymer which is recyclable. The liquid impermeable layer may be less elastic than polyethylene. LDPE (low density polyethylene), which has conventionally been used to provide a liquid impermeable layer to fibre based containers such as paper cups has a modulus of elasticity of 0.13 to 0.30 GPa. Thus, in embodiments of the invention, the liquid impermeable layer may have a modulus of elasticity equal to orgreaterthan about 0.3 GPa, equal to orgreaterthan about 0.5 GPa, equal to or greater than about 1 GPa, equal to or greater than about 5 GPa or equal to or greater than about 10 GPa. In some embodiments, the modulus of elasticity of the liquid impermeable layer may have a modulus of elasticity of about 1 GPa to about 1000 GPa, about 5 GPa to about 500 GPa or about 10 to about 100 GPa. Where reference is made to quantified modulus of elasticity values herein, these are calculated in accordance with ASTM D638 - Standard Test Method for Tensile Properties of Plastics. In embodiments, the liquid impermeable layer comprised on the inner wall surface and the inner base surface is the same. In alternative embodiments, the liquid impermeable layer comprised on the inner wall surface and the inner base surface is different. As discussed below, whether the liquid impermeable layer comprised on the inner wall surface and the inner base surface is the same or different, a sealable lacquer coating may be comprised on the sealing portions of those surfaces. The liquid impermeable layer may have any thickness provided that it provides effective liquid barrier properties. The effective thickness of the layer will depend, to a certain extent, on the material used to form the layer. However, in embodiments of the invention, the thickness of the liquid impermeable layer comprised on the inner wall surface and I or the inner base surface may be from about 1 to about 100 pm, about 5 to about 50 pm, about 10 to about 25 pm or about 12 to 20 pm. Additionally or alternatively, the liquid impermeable layer may have a weight of from about 1 to about 20 g / m2, about 2 to about 12 g / m2 or about 3 to about 8 g / m2. In some embodiments, the weight / thickness of the liquid impermeable layer applied to the inner wall surface may be greater than that applied to the inner base surface. In certain embodiments, the weight / thickness of the liquid impermeable layer applied to the inner base surface may be greater than that applied to the inner wall surface. In other embodiments, the weight / thickness of the liquid impermeable layer applied to the inner wall surface may be the same as that applied to the inner base surface. The liquid impermeable layer may be applied in liquid form (e.g. in the form of a solution or an emulsion) and then dry (air-dried, via the application of heat, or the like) to provide the liquid impermeable barrier. In such embodiments, the liquid impermeable barrier may be applied to the inner wall surface and I or the inner base surface using any technique known to those skilled in the art, for example, by printing, brushing, spraying or the like. As explained herein, the function of the liquid impermeable layer is to provide a barrier to moisture and liquid passing into the cup wall or base, which can result in saturation of the wall and I or base paper fibres and leakage of the liquid therefrom. In embodiments, the liquid impermeable layer may provide the wall and I or base, respectively, with a Cobbeo value of less than about 10g / m2, less than about 5g / m2, less than about 2g / m2, less than about 1g / m2, or about 0 g / m2. Cobbeo values are measured in accordance with ISO standard 535 (Paper and Board). In a further embodiment, the liquid impermeable layer comprises an inorganic mineral. The outer wall surface and I or outer base surface may or may not comprise a liquid impermeable layer. In embodiments, the outer wall surface and / or outer base surface may comprise a varnish (for example an overall protective varnish). This may be the same material or different to the sealable lacquer employed in aspects of the present invention. In embodiments, the liquid impermeable layer may be inherently sealable. Whether it is or not, a sealable lacquer may be applied to the quadrilateral blank (e.g. along the first and I or second edge sealing portion) and I or the base (e.g. along the wall sealing portion). In embodiments, one or both of the base sealing portion and the wall sealing portion comprise a sealable lacquer coating and the sealable lacquer coating is present within the base seam. Additionally or alternatively, one or both of the first and second edge sealing portions comprise a sealable lacquer coating and the sealable lacquer coating is present within the wall seam. In certain embodiments of the invention, the sealable lacquer coating is provided on top of the liquid impermeable layer, for example on the wall sealing portion, on the base sealing portion, on the first edge sealing portion and I or the second edge sealing portion. Any type of food approved sealable lacquer coating may be employed in the present invention provided that it is capable of providing a liquid resistant seal upon activation. In some embodiments, the lacquer coating may be heat sealable (e.g. at a temperature of around 100°C to about 250°C), for example it may be sealable via contact with hot pressured air. Additionally or alternatively, the lacquer coating may be ultrasonically sealable (e.g. at a frequency of around 20mHz to about 40mHz). Other types of sealable lacquer coating could also be employed, e.g. pressure sealable lacquer coatings. In certain embodiments, the sealable lacquer coating and I or the liquid impermeable layer may be free of fluorinated compounds. In some embodiments, the sealable lacquer coating and I or the liquid impermeable layer may be free of poly- and perfluoroalkyl substances (PFAS), for example perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA). In embodiments of the invention, the sealable lacquer coating materials that may be employed are those which are environmentally friendly, for example which are biodegradable. Advantageously, unlike conventional fibre based containers comprising polyethylene based liquid impermeable layers, this permits containers to be composted at home or industrially following disposal of the container. Specific lacquer coating materials which may be utilised include polyvinylacetate and acrylic lacquers. The sealable lacquer coating may be applied at a coating weight of about 1 to about 50 g / m2, about 3 to about 30 g / m2, about 5 to about 25 g / m2, about 6 to about 22 g / m2, about 8 to about 20 g / m2 or about 10 to about 15 g / m2. In embodiments in which the base sealing portion and the wall sealing portion both are provided with sealable lacquer, the weight of the sealable lacquer provided in the wall sealing portion may be greater than the weight of the sealable lacquer provided in the base sealing portion. For example, the weight of the sealable lacquer provided in the wall sealing portion may be about 5 to about 20 g / m2, about 6 to about 15 g / m2 or about 10 to about 15 g / m2. Additionally or alternatively, the weight of the sealable lacquer provided in the base sealing portion may be about 3 to about 15 g / m2, about 5 to about 10g / m2 or about 6 to about 8 g / m2. In certain embodiments, the thickness of the sealable lacquer coating applied to the inner base surface is consistent. For example, the thinnest part of the sealable lacquer coating applied to the inner base is no less than about 20%, no less than about 30%, no less than about 40%, no less than about 50%, no less than about 60%, no less than about 70% or no less than about 80% of the thickness of the thickest part of the sealable lacquer coating applied to the inner base surface. The sealable lacquer coating preferably is elastic. In preferred embodiments, the sealable lacquer coating is more elastic than the liquid impermeable layer, i.e. it has a lower modulus of elasticity than the liquid impermeable layer. For example, the sealable lacquer coating may have a modulus of elasticity of less than about 5 GPa, less than about 2 GPa, less than about 1 GPa, less than about 0.5 GPa, less than about 0.2 GPa or less than about 0.1 GPa. In some embodiments, the sealable lacquer coating has a modulus of elasticity of about 0.01 GPa to about 1 GPa, about 0.012 GPa to about 0.5 GPa or about 0.015 to about 0.1 GPa. Where reference is made herein to the sealable lacquer coating being comprised on or in a region or portion of a component, the sealable lacquer coating may be comprised on the entirety of that region or portion or a substantial part thereof. In embodiments, the entirety of the inner base surface does not comprise the sealable lacquer coating, i.e. the inner base surface comprises a central portion which does not comprise sealable lacquer coating. The quadrilateral blank (and thus tubular wall component) and I or the circular base component may comprise any suitable fibre based substrate, but preferably comprise a paperboard substrate, such as, but not limited to, cupstock and the like. In embodiments of the invention, the material from which the quadrilateral blank I tubular wall component and the base component are formed may be the same or different. In some embodiments, the fibre based substrate is clay-coated, optionally on the inner wall surface. The quadrilateral blank I tubular wall component and the circular base component may have any thickness which provides sufficient structural strength to the assembled container. In embodiments, the quadrilateral blank I tubular wall component and I or the circular base component may have a thickness (excluding the impermeable liquid layer and any sealable lacquer coating) of about 200pm to about 2000pm, about 250pm to about 1000pm, about 300pm to about 500pm or about 350pm to about 500pm. Additionally or alternatively, the quadrilateral blank I tubular wall component and I or the circular base component may be formed from fibre based substrate having a weight of about 150 to about 500 g / m2, about 180 to about 350 g / m2, about 200 to about 330 g / m2 or about 250 to about 300 g / m2. In embodiments the circular base component is formed from fibre based substrate having a weight greater than 250 g / m2, greater than 255 g / m2 or greater than 260 g / m2. In some embodiments, the fibre based substrate comprised in the tubular wall component I quadrilateral blank has a heavier weight than the fibre based substrate comprised in the circular base component. In certain embodiments, the fibre based substrate comprised in the circular base component has a heavier weight than the fibre based substrate comprised in the tubular wall component I quadrilateral blank. In other embodiments, the fibre based substrate comprised in the tubular wall component I quadrilateral blank has the same weight as the fibre based substrate comprised in the circular base component. In embodiments of the invention, the circular base component is substantially planar, save for the folded portion which is folded at an angle from the remainder of the circular base component. The circular base component may have a diameter of from about 30mm to about 100mm, about 35mm to about 80mm, or about 40mm to about 65mm. As those skilled in the art will recognise, the tubular wall component may be perfectly cylindrical. In other embodiments, the tubular wall component may not be perfectly cylindrical. For example, it may be tapered, e.g. in the form of a truncated cone and I or such that the diameter of the tubular wall component at the end at which the base seal is formed is smaller than the diameter of the tubular wall component at its opposite end. The process of the invention as defined herein comprises 4 parts, one or more of which may be comprised in the process. For example, in embodiments, part 1) is performed, part 2) is performed, part 3) is performed or part 4) is performed. In some embodiments, two of the claimed parts may be performed, for example part 1) and part 2), part 1) and part 3), part 1) and part 4), part 2) and part 3), part 2) and part 4) or part 3) and part 4). In some embodiments, three of the claimed parts may be performed, for example, part 1), part 2) and part 3); part 1), part 2) and part 4); part 1), part 3) and part 4) or part 2), part 3) and part 4). In other embodiments, all of parts 1) to 4) are performed. According to a further aspect of the present invention, there is provided a container obtainable from the process of the invention. The container of the invention in embodiments may be a fibre based packaging container for holding liquids, the packaging container comprising: a. a tubular wall component comprising an upper end, a lower end, an inner wall surface and an outer wall surface opposing the inner wall surface, the inner wall surface comprising a liquid impermeable layer and a base sealing portion at the lower end of the tubular wall component; and b. a circular base component comprising an outer edge, an inner base surface and an outer base surface opposing the inner base surface, the inner base surface comprising a liquid impermeable layer, a fold line extending circumferentially around the inner base surface, and a wall sealing portion located on the inner base surface between the outer edge of the base and the fold line, wherein the circular base component is folded at 80 to 100 degrees about the fold line to form a folded portion comprising the wall sealing portion, and wherein: i. the upper end of the tubular wall component comprises a rolled rim comprising a second liquid impermeable layer, ii. the inner wall surface and I or the inner base surface comprises a further liquid impermeable layer, Hi. the tubular wall component comprises an interior which comprises an exposed edge of the tubular wall component which comprises a liquid impermeable layer and / or a sealable lacquer coating, and / or iv. a portion of the inner wall surface and / or the outer wall surface extending partially along that surface from the upper edge of the tubular wall component comprises an additional layer of liquid impermeable barrier material and I or sealable lacquer. The container of the invention may be a cup. The present application discloses multiple aspects of the invention, e.g. containers, components of the container, quadrilateral blanks, and methods of and apparatus for preparing a container. Unless otherwise stated, the disclosure of features in connection with one aspect of the invention is not limited to those features only being provided in connection with that aspect. To the contrary, where a feature of a component is disclosed in connection with one aspect of the invention, it may also be provided in the corresponding component of any other aspect of the invention. BRIEF DESCRIPTION OF THE DRAWINGS Figures 1 and 2 are photographs showing the absorbance of coffee into the upper portion of a container not produced according to the process of the present invention. Figure 3 is a photograph showing the lack of absorbance of coffee into the upper portion of a container produced according to the process of the invention. The invention will now be illustrated by the example which follows. Example 1 - Testing of Liquid Absorbance into Container Base Paper cups were manufactured as discussed herein. The wall and base of the cup were produced from clay-coated cup-stock of standard weight. A mineral coating comprising silica was applied to the inner base surface of the base and the innerwall surface of the quadrilateral blank as an emulsion, at a coating weight of~5g / m2 and permitted to dry. For a first group of cups (comparators), the rim was rolled but no further treatment was conducted. For a second group of cups (inventive), the same mineral coating as applied to the interior of the cup was applied to the upper part of the rolled rim from above the cup at a coating weight of 0.1g per cup, the second and fourth edges had acrylic lacquer applied to them at a weight of 0.05g per blank, and the interior of the cup was sprayed with a second layer of mineral coating at a weight of 0.2g per cup. Coffee at a temperature of ~95°C was filled into the cups and left for 60 minutes. Following that time, the upper part of the first group of cups had absorbed an unacceptable volume of fluid as shown in Figure 1 (in which a lid was applied to the cup for the 60 minute testing period) and Figure 2 (in which no lid was applied), whereas, as shown in Figure 3, the upper part of the second group of cups was resistant to moisture ingress, despite having a lid applied during the 60 minute testing period. Further no liquid ingress was observed in the interior of the second group of cups.

Claims

05 06 251. A method of manufacture of a fibre-based packaging container, wherein the method comprises the steps of:a. providing a quadrilateral blank comprising an inner wall surface and an outer wall surface opposing the inner wall surface, the inner wall surface comprising a liquid impermeable layer, the quadrilateral blank further comprising a first edge and second edge opposing the first edge, wherein the first and second edges are linear, and a third edge and a fourth edge opposing the third edge, each of the third and fourth edges defining an arc, wherein a first edge sealing portion extends partially across the inner wall surface from the first edge and a second edge sealing portion extends partially across the outer wall surface from the second edge, and wherein a base sealing portion extends partially across the inner wall surface adjacent the third edge;b. providing a circular base component having an outer edge, an inner base surface and an outer base surface opposing the inner base surface, the inner base surface having a liquid impermeable layer and comprising a wall sealing portion;c. flexing the quadrilateral blank to bring the first and second edges into overlapped engagement with one another, and sealing them to one another to form a tubular wall component with a wall seam, the tubular wall component having an interior, an exterior, an upper end and a lower end at which the base sealing portion is located;d. folding the circular base component at a fold line around the whole of the circular base component to create a circumferentially folded edge extending at 80 to 100 degrees from the rest of the circular base component wherein the circumferentially folded edge comprises the wall sealing portion, and the circumferentially folded edge and the outer base surface define a base interior;e. sealing the wall sealing portion and the base sealing portion to one another to form a base seam between the tubular wall component and the circular base component;05 06 25wherein the process further comprises the step of rolling the fourth edqe of the quadrilateral blank or the upper edge of the tubular wall component to form a rolled rim and applying a second liquid impermeable layer to the rolled rim wherein the second liquid impermeable layer is applied in liquid form and then dried.

2. The process of Claim 1, wherein the second liquid impermeable layer is applied to the upper part of the rolled rim.

3. The process of Claim 1 or 2, wherein the second liquid impermeable layer is applied to the rolled rim via an applicator comprising a permeable region in fluid communication with a supply of the second liquid impermeable layer material, and the permeable region is contacted with the upper part of the rolled rim.

4. The process of Claim 3, wherein the permeable region of the applicator is resilient and I or elastic.

5. The process of Claim 3 or 4, wherein the applicator comprises a spray nozzle in fluid communication with a supply of the further liquid impermeable layer material.

6. The process of Claim 5, wherein the applicator is used to apply a second liquid impermeable layer to the rolled rim and also to apply a further liquid impermeable layer to the interior of the tubular wall component and I or the inner base surface .

7. The process of Claim 1 or 2, wherein the second liquid impermeable layer is applied using a spray.

8. The process of any one of Claims 1 to 7, wherein the second edge of the quadrilateral blank is provided with a liquid impermeable layer and / or a sealable lacquer coating.

9. The process of any one of Claims 1 to 8, wherein a part of the second edge extending from the third edge of the quadrilateral blank and a part of the third edge extending from the second edge of the quadrilateral blank are provided with a liquid impermeable layer and / or a sealable lacquer coating.

10. The process of any one of Claims 1 to 9, wherein a part of the second edge extending from the fourth edge of the quadrilateral blank and a part of the fourth edge extending from the second edge of the quadrilateral blank are provided with a liquid impermeable layer and / or a sealable lacquer coating.

11. The process of any one of Claims 1 to 10, wherein one or both of the base sealing portion and the wall sealing portion comprise a sealable lacquer coating and the seal-able lacquer coating is present within the base seam.

12. The process of any one of Claims 1 to 11, wherein a portion of the inner wall surface or the outer wall surface extending partially along that surface from the fourth edge of the quadrilateral blank or the upper edge of the tubular wall component comprises a sealable lacquer layer and an additional layer of liquid impermeable barrier material applied thereupon.05 06 25

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