Patent Publication Number: US-2018037361-A1

Title: Improved container with non-squared edges

Description:
The present invention relates to a container for consumer goods and to a blank for forming such container, which find particular application for holding consumer goods, such as smoking articles (for example cigarettes). 
     Smoking articles such as cigarettes and cigars are usually provided in soft-pack packs or hard-pack packs, such as flip-top boxes or hinge-lid boxes. These typically have a box part having a box front wall, a box rear wall, box side walls and a box base. They also usually have a lid part with a lid front wall, a lid rear wall, lid side walls and a lid top side. The lid part is typically hinged to the box part along a hinge line extending across a back wall of the container. The hinge line is usually provided as a pre-folded line, a crease line or a score line. 
     For hard-pack packs, it is known to round off or chamfer certain corners of the box and lid to give the container a distinctive appearance. This has typically been achieved in the past by providing creasing lines or score lines in the blank at the areas forming the edges of the container. These lines allow the blank to be folded in such a way that the corner does not sharply bend but instead progressively bends between two adjacent walls. 
     However, where a container comprises adjacent rounded or bevelled edges forming an angle, such as an orthogonal angle, the strength and finish of the container may at times be impacted during folding of the blank to form the container. In some cases, a hole or gap can even be formed at the junction between the adjacent rounded or bevelled edges. Thus, not only is the visual and tactile perception of the container impacted, but also the container may be structurally damaged. 
     Thus, it would be desirable to provide a container for consumer goods that is less prone to being damaged during the assembly operation and that has an improved look and a smoother feel. In particular, it would be desirable that one such container be easy to assemble using standard packing apparatus and techniques, without the requirement for significant changes to existing machines and methods. At the same time, it would be desirable to provide a blank for manufacturing a container for consumer goods that makes the production and assembly process easier, more flexible and less likely to cause damages in the assembled container. 
     According to a first aspect of the present invention, there is provided a container for consumer articles, the container being at least partially formed from a laminar blank having a thickness (T). The laminar blank defines a portion of the container, which comprises a first planar wall, a second planar wall connected to the first planar wall by a first edge portion, and a third planar wall connected to the first planar wall by a second edge portion. The longitudinal direction of the first edge portion is transverse to the longitudinal direction of the second edge portion. The first edge portion and the second edge portion form, when the container is assembled from the laminar blank, adjacent edges of the container meeting at a junction. Each of the first and the second edge portions has an inner surface and an outer surface. The inner surfaces of the first and second edge portions define a first ablation area (A1) and a second ablation area (A2), respectively. Each ablation area (A1, A2) comprises one or more ablated zones having a residual thickness less than the thickness (T) of the laminar blank, and each ablation area (A1, A2) has a length in the longitudinal direction of the respective edge portion and a respective width that extends transversely to the length. In addition, at least one of the first and second ablation areas (A1, A2) comprises a first portion and an end portion extending from the first portion, the end portion tapering from a width (W) of the first portion to a point at the junction with the other one of the first and second ablation areas (A1, A2). 
     According to a second aspect of the present invention, there is provided a laminar blank for forming a container for consumer articles. The laminar blank has a thickness (T) and comprises: a first wall panel for forming a first planar wall of the container; a second wall panel connected to the first wall panel by a first edge portion for forming a second planar wall of the container; and a third wall panel connected to the first wall panel by a second edge portion for forming a third planar wall of the container. The longitudinal direction of the first edge portion is transverse to the longitudinal direction of the second edge portion. The first edge portion and the second edge portion form, when the container is assembled from the laminar blank, adjacent edges of the container meeting at a junction. The first and the second edge portions have an inner surface and an outer surface. The inner surfaces of the first and second edge portions define a first ablation area (A1) and a second ablation area (A2), respectively. Each ablation area (A1, A2) comprises one or more ablated zones having a residual thickness less than the thickness (T) of the laminar blank. Further, each ablation area (A1, A2) has a length in the longitudinal direction of the respective modified edge portion and a respective width that extends transversely to the length. In addition, at least one of the first and second ablation areas (A1, A2) comprises a first portion and an end portion extending from the first portion and tapering from a width (W) of the first portion to a point at the junction with the other one of the first and second ablation areas (A1, A2). 
     It shall be appreciated that any features described with reference to one aspect of the present invention are equally applicable to any other aspect of the invention. 
     In contrast to known blanks/containers, where material is removed within the portions of the blank that form two adjacent non-squared (for example, rounded or bevelled) corners of the container, at least one of the ablation areas tapers towards the intersection with the adjacent ablation area. In more detail, material is removed within an ablation area extending substantially along an edge of a planar wall of the container. The ablation area comprises a first portion, for example one having a substantially constant width over at least a part of its length, and at least a tapered end portion extending from the first portion to the intersection of the ablation area with another ablation area extending substantially along an adjacent edge of the same planar wall of the container. 
     Because the interference between adjacent ablation areas is limited, if not eliminated altogether, the risk of damaging the blank/container during the folding operation is significantly reduced. Thus, bending of the blank when forming the container is easier and results in the formation of surfaces that are smoother to the touch. At the same time, the strength of the container at rounded/bevelled edges may be better preserved. 
     Thus, it is easy to form non-squared edges, such as rounded or bevelled edges, in a container according to the present invention. When the blank is bent into shape at the rounded or bevelled edges, a portion of the total deflection is absorbed by each reduced thickness portion of the ablation area, so that the resulting container edge advantageously gets to assume the desired shape more smoothly than it would be if it were formed with sharp creases. Further, because of the tapered shape and mutual arrangement of adjacent ablated zones, adjacent rounded or bevelled edges of the containers are formed without any significant damage to the blank or container that could be caused by interfering ablated zones. Thus, the risk of forming holes or gaps in the container during the assembly operation is advantageously greatly reduced. 
     Because the outer surface of the blank is unaffected by the ablation process, the resulting outer surface of the container is smooth upon visual and tactile inspection on the part of the consumer. Further, because this smooth, rounded surface can be obtained with a relatively small number of ablated zones, and therefore with limited material removal, the strength of the container at the rounded or bevelled corners may be adjusted, so that appearance and resistance of the container are both advantageously improved. 
     Advantageously, the blank may be manufactured by precisely removing material from the round corner portion with a linear ablation tool (e.g. laser, blade). Repeated passages of the ablation tool over a given portion of the blank results in the controlled removal of a greater percentage of material, that is in a reduced residual thickness. 
     The term “edge portion” is used herein to refer in particular to an edge portion of the container having a non-square shape as viewed in cross-section. This may for example refer to a “curved edge portion”, that is an edge portion of the container having an arc-like shape as viewed in cross-section. By the term “arc-like” reference is made to any non-straight line, including circular arc, parabolic arc, hyperbolic arc, elliptical arc, etc. Further, this may for example refer to a “bevelled edge portion”, that is an edge portion of the container that has, as viewed in cross-section, a substantially straight shape forming an angle between 0 and 90 degrees with the adjacent walls of the container. 
     The term “inner surface” is used throughout the specification to refer to the side of a portion of the blank that, once the container is assembled, faces towards the interior of the container, for example towards the consumer goods, when the container is closed. Thus, the inner surface is not directly visible for the consumer when the container is closed. The term “outer surface” is used throughout the specification to refer to the side of a portion of the blank that, once the container is assembled, faces towards the exterior of the container. 
     The term “ablation area” is used herein to refer to the minimum area of the blank that encloses all ablated zones on an edge portion. 
     The term “ablated zone” is used herein to refer to an area of the curved edge portion from which material has been ablated (for example, removed by means of a laser beam or a blade) from a surface of the laminar blank or container. Accordingly, the residual thickness of an ablated zone is less than the thickness (T) of the laminar blank. Preferably, an ablated zone is provided as a groove within the blank. This may be formed with a linear ablation tool, such as a laser or a blade. In embodiments where all the ablated zones are defined by parallel grooves within the blank, the area of the ablation area may be regarded as the area enclosing all the grooves on the curved edge portion. Thus, in those embodiments, the width of the ablation area may be regarded as extending transversely to the grooves, from the first to the last of the grooves on the curved edge portion. 
     In the present specification, the term “slanted” is used to describe a section of an ablated zone that extends along a direction forming a non null angle with respect to a reference direction, for example the longitudinal direction of the ablation area, or the axis of a wall of the container. For example, a “slanted” section of an ablated zone may extend along said direction in its entirety. In other words, a “slanted” section of an ablated zone may extend along a substantially straight line. As an alternative, the direction along which a “slanted” section of an ablated zone extends may vary. Thus, a “slanted” section of an ablated zone may substantially extend along a polyline or a curved line. 
     The term “residual thickness” is used herein to refer to the minimum distance measured between two opposite surfaces of the laminar blank or of a wall of the container formed from the blank. In practice, the distance at a given location is measured along a direction locally perpendicular to the opposite surfaces. The “residual thickness” of an ablated zone may be constant over the ablated zone if material is removed homogenously substantially all over the ablated zone (flat profile). Alternatively, the residual thickness of the ablated zone may vary across a width of the ablated zone, if material is removed non-homogeneously over the ablated zone (e.g. V-shaped, U-shaped grooves). 
     As used herein, the terms “front”, “back”, “upper”, “lower”, “top”, “bottom” and “side”, refer to the relative positions of portions of containers according to the invention and components thereof when the container is in an upright position with the access opening at the top of the container. In particular, where the container is a hinged lid container, this refers to the container being in an upright position with the lid in the closed position and the hinge line at the back of the container. When describing containers according to the present invention, these terms are used irrespective of the orientation of the container being described. 
     The term “spring-back force” is a known term of art for referring to a particular property of a laminar blank. It is sometimes referred to as ‘the crease recovery’ and means the force (N) required to hold a scored sample that is folded at 90 degrees for a 15-second period. The measurement is made at the end of the 15-second period. The spring-back force of a portion of a laminar blank can be measured using a known PIRA Crease and Board Stiffness Tester (commercially available for example from Messmer and Buchel, UK). As is known in the art, to measure the spring-back force of a curved edge portion of a container, a sample of the portion to be tested should first be removed from the laminar blank. For round corner packs, for the purposes of the present invention the spring-back force of a pack is assessed using a sample measuring 38±1 millimetres by 38±0.5 millimetres, with the corner forming portion being positioned 21±0.5 millimetres from one side of the blank. The blank should be conditioned at 22 degrees Celsius and 60 percent relative humidity for at least 24 hours prior to testing. 
     In its most general terms, a container according to the present invention is at least partially formed from a laminar blank having a thickness (T). In more detail, the laminar blank defines a portion of the container, which comprises a first planar wall, a second planar wall connected to the first planar wall by a first edge portion; and a third planar wall connected to the first planar wall by a second edge portion. The longitudinal direction of the first edge portion is transverse to the longitudinal direction of the second edge portion and the first edge portion and the second edge portion form, when the container is assembled from the laminar blank, adjacent edges of the container meeting at a junction. Each of the first and the second edge portions have an inner surface and an outer surface, and the inner surfaces of the first and second edge portions define a first ablation area (A1) and a second ablation area (A2), respectively. Each ablation area (A1, A2) has a length in the longitudinal direction of the respective edge portion and a respective width that extends transversely to the length, and comprises one or more ablated zones having a residual thickness less than the thickness (T) of the laminar blank. At least one of the first and second ablation areas (A1, A2) comprises a first portion and an end portion extending from the first portion, the end portion tapering from a width (W) of the first portion to a point at the junction with the other one of the first and second ablation areas (A1, A2). 
     In some embodiments, both the first and second ablation areas (A1, A2) comprise a respective first portion and a respective end portion extending from the respective first portion and tapering from a width of the respective first portion to a point at the junction with the other one of the first and second ablation areas (A1, A2). In these embodiments, a corner portion of the first planar wall is delimited by a slanted ablated zone of the end portion of the first ablation area (A1) and by a slanted ablated zone of the second ablation area (A2), each slanted ablated zone forming a non null angle with the longitudinal direction of the respective edge portion. 
     This is thought to minimise the interaction between the adjacent edge portions, and so the risk of damaging the container during the assembly process is particularly limited. In addition, the finish and look of the container are advantageously enhanced. 
     Preferably, each ablation area (A1, A2) comprises a first ablated zone and a second ablated zone extending in parallel in the longitudinal direction of the edge portion within the first portion of the ablation area. In addition, each of the first and second ablated zones is arranged proximate to a respective one of the first planar wall and the second or third planar wall. 
     Preferably, at least one of the first ablation area (A1) and the second ablation area (A2) comprises a plurality of ablated zones, all the ablated zones extending in parallel in the longitudinal direction of the edge portion within the first portion of the ablation area. 
     In addition, at least one ablated zone preferably extends along a straight line in the longitudinal direction of the modified edge portion over at least part of the tapering end portion of the first ablation area (A1) or the second ablation area (A2). This can help to further weaken the tapering end portion of the laminar blank. This can help to create a more gradual curvature and profile in the container around the junction at which adjacent edges of the container meet. 
     In the embodiments identified above, at least one ablated zone preferably comprises a slanted section extending, over part of the tapering end portion of the ablation area, along a direction forming a non null angle with the longitudinal direction of the modified edge portion. 
     In addition, at least one of the first ablation area (A1) and the second ablation area (A2) preferably comprises a first pair of ablated zones extending in the longitudinal direction of the modified edge portion over at least part of the tapering end portion of the ablation area, and a second pair of ablated zones comprising respective slanted sections forming a non null angle with the first pair of ablated zones. The ablated zones in the second pair of ablated zones are symmetrical with respect to the ablated zones in the first pair of ablated zones. 
     In alternative embodiments, the first ablation area (A1) comprises a first portion and an end portion extending from the first portion and tapering from a width of the first portion to a point at the junction with the second ablation area (A2), as described above, whereas the second ablation area (A2) comprises a plurality of ablated zones extending in the longitudinal direction of the edge portion over the whole length of the second ablation area (A2). Thus, in these embodiments, a corner portion of the first planar wall is delimited by a straight ablated zone of the second ablation area (A2) and by a slanted ablated zone of the end portion of the first ablation area (A1) forming a non null angle with the longitudinal direction of the first edge portion. 
     In some embodiments, the laminar blank defines a portion of the container that comprises a first planar wall, a second planar wall connected to the first planar wall by a first edge portion; a third planar wall connected to the first planar wall by a second edge portion; and a fourth planar wall connected to the first planar wall by a third edge portion. The longitudinal direction of the first edge portion is transverse to the longitudinal direction of the second edge portion and to the longitudinal direction of the third edge portion. The longitudinal direction of the second edge portion is substantially parallel to the longitudinal direction of the third edge portion. When the container is assembled from the laminar blank, the first edge portion and the second edge portion form adjacent edges of the container meeting at a first junction. Similarly, in the assembled container, the first edge portion and the third edge portion form adjacent edges of the container meeting at a second junction. Each of the first, second and third edge portions have an inner surface and an outer surface, and the inner surfaces define a first ablation area (A1), a second ablation area (A2), and a third ablation area (A3) respectively. Each ablation area (A1, A2, A3) has a length in the longitudinal direction of the respective edge portion and a respective width that extends transversely to the length, and comprises one or more ablated zones having a residual thickness less than the thickness (T) of the laminar blank. The first ablation area (A1) comprises a first portion and two opposite end portions extending from the first portion, each end portion tapering from a width (W) of the first portion to a point at the junction with a respective one of the second and third ablation areas (A2, A3). 
     Preferably, each of the ablation lines has a residual thickness of at least about 5 percent of the thickness (T) of the blank. More preferably, each of the ablation lines has a residual thickness of at least about 10 percent of the thickness (T) of the blank. Even more preferably, each of the ablation lines has a residual thickness of at least about 20 percent of the thickness (T) of the blank. In addition, or as an alternative, each of the ablation lines has preferably a residual thickness of less than about 50 percent of the thickness (T) of the blank. More preferably, each of the ablation lines has a residual thickness of less than about 40 percent of the thickness (T) of the blank. Even more preferably, each of the ablation lines has preferably a residual thickness of less than about 30 percent of the thickness (T) of the blank. In some particularly preferred embodiments, each of the ablation lines has preferably a residual thickness of about 20 percent of the thickness (T) of the blank. 
     Preferably, the ablated width of each ablated zone is at least about 0.01 millimetres. More preferably, the ablated width of each ablated zone is at least about 0.05 millimetres. In addition, or as an alternative, the ablated width of each ablated zone is less than about 0.4 millimetres. More preferably, the ablated width of each ablated zone is less than about 0.2 millimetres. In some preferred embodiments, the ablated width of each ablated zone is from about 0.01 millimetres to about 0.4 millimetres. Even more preferably, the ablated width of each ablated zone is from about 0.05 millimetres to 0.2 millimetres. 
     Preferably, the container has a spring-back force of less than about 10 milliNewton metres between the two planar walls that are connected by the curved edge portion. 
     Containers according to the present invention find application as containers for consumer goods, in particular elongate consumer goods such as smoking articles. However, they can also be used for several other types of consumer goods. 
     The blank may be formed from any suitable material or combination of materials, including, but not limited to, cardboard, paperboard, plastic, metal, or combinations thereof. Preferably, the blank is a laminar cardboard blank having a weight of between about 100 grams per square metre and about 350 grams per square metre. In preferred embodiments, the blank has a thickness of from about 100 micrometres to about 500 micrometres, preferably from about 200 micrometres to about 350 micrometres. 
     The container may optionally comprise an outer wrapper, which is preferably a transparent polymeric film of, for example, high or low density polyethylene, polypropylene, oriented polypropylene, polyvinylidene chloride, cellulose film, or combinations thereof and the outer wrapper is applied in a conventional manner. The outer wrapper may include a tear tape. In addition, the outer wrapper may be printed with images, consumer information or other data. 
     Further, the consumer articles may be provided within the container in the form of a bundle wrapped in an inner package formed of metal foil or metallised paper. The inner package material may be formed as a laminate of a metallised polyethylene film, and a liner material. The liner material may be a super-calendered glassine paper. In addition, the inner package material may be provided with a print-receptive top coating. The inner package has an access opening through which consumer goods can be removed when a lid of the container is in a respective open position. 
     The container is preferably a rectangular parallelepiped comprising two wider walls spaced apart by two narrower walls. Hinge lid containers according to the invention may be in the shape of a rectangular parallelepiped, with right-angled longitudinal and right-angled transverse edges. Alternatively, the hinge lid container may comprise one or more rounded longitudinal edges, rounded transverse edges, bevelled longitudinal edges or bevelled transverse edges, or combinations thereof. For example, the hinge lid container according to the invention may comprise, without limitation:
         One or two longitudinal rounded edges on the front wall, and/or one or two longitudinal rounded or bevelled edges on the back wall.   One or two transverse rounded edges on the front wall, and/or one or two transverse rounded or bevelled edges on the back wall.   One longitudinal rounded edge and one longitudinal bevelled edge on the front wall, and/or one transverse rounded edge and one transverse bevelled edge on the back wall.   One or two transverse rounded or bevelled edges on the front wall and one or two longitudinal rounded or bevelled edges on the front wall.   Two longitudinal rounded or bevelled edges on a first side wall or two transverse rounded or bevelled edges on the second side wall.       

     Where the container comprises one or more bevelled edge, preferably the bevelled edge has a width of between about 1 mm and about 10 mm, preferably between about 2 and about 6 mm. Alternatively, the container may comprise a multi-bevelled edge formed by parallel creasing or scoring lines that are spaced such that two or more distinct bevels are formed on at least one edge of the container. 
     Alternatively, the container may have a non-rectangular transversal cross section, for example polygonal such as triangular or hexagonal, semi-oval or semi-circular. 
     Containers according to the invention find particular application as packs for elongate smoking articles such as, for example, cigarettes, cigars or cigarillos. It will be appreciated that through appropriate choices of the dimensions thereof, containers according to the invention may be designed for different numbers of conventional size, king size, super-king size, slim or super-slim cigarettes. Alternatively, other consumer goods may be housed inside the container. 
     Through an appropriate choice of the dimensions, containers according to the invention may be designed to hold different total numbers of smoking articles, or different arrangements of smoking articles. For example, through an appropriate choice of the dimensions, containers according to the invention may be designed to hold a total of between ten and thirty smoking articles. 
     The smoking articles may be arranged in different collations, depending on the total number of smoking articles. 
     Containers according to the present invention may hold smoking articles of the same type or brand, or of different types or brands. In addition, both filter-less smoking articles and smoking articles with various filter tips may be contained, as well as smoking articles of differing length (for example, between about 40 mm and about 180 mm), diameter (for example, between about 4 mm and about 9 mm). Preferably, the dimensions of the container are adapted to the length of the smoking articles, and the collation of the smoking articles. Typically, the outer dimensions of the container are between about 0.5 mm to about 5 mm larger than the dimensions of the bundle or bundles of smoking articles housed inside the container. 
     The length, width and depth of containers according to the invention may be such that the resultant overall dimensions of the container are similar to the dimensions of a typical disposable pack of twenty cigarettes. 
     Preferably, containers according to the invention have a height of between about 60 mm and about 150 mm, more preferably a height of between about 70 mm and about 125 mm, wherein the height is measured from the bottom wall to the top wall of the container. 
     Preferably, containers according to the invention have a width of between about 12 mm and about 150 mm, more preferably a width of between about 70 mm and about 125 mm, wherein the width is measured from one side wall to the other side wall of the container. 
     Preferably, containers according to the invention have a depth of between about 6 mm and about 150 mm, more preferably a depth of between about 12 mm and about 25 mm wherein the depth is measured from the front wall to the back wall of the container. 
     Preferably, the ratio of the height of the container to the depth of the container is in between about 0.3 to 1 and about 10 to 1, more preferably between about 2 to 1 and about 8 to 1, most preferably between about 3 to 1 and 5 to 1 
     Preferably, the ratio of the width of the container to the depth of the container is in between about 0.3 to 1 and about 10 to 1, more preferably between about 2 to 1 and about 8 to 1, most preferably between about 2 to 1 and 3 to 1. 
     Preferably, the ratio of the height of the lid back wall to the height of the box back wall of the outer sleeve is between about 0 to 1 (lid located at the top edge of the container) to about 1 to 1, more preferably, between about 1 to 5 and about 1 to 10, most preferably, between about 1 to 6 to about 1 to 8. 
     Preferably, the ratio of the height of the lid front wall of the outer sleeve to the height of the box front wall of the outer sleeve is between about 1 to 0 (lid covering the entire front wall) to about 1 to 10, more preferably, between about 1 to 1 and about 1 to 5, most preferably, between about 1 to 2 and about 1 to 3. 
     The exterior surfaces of containers according to the invention may be printed, embossed, debossed or otherwise embellished with manufacturer or brand logos, trade marks, slogans and other consumer information and indicia. 
     Containers according to the invention may be filled and assembled using conventional apparatus and methods, modified to include the step of forming the ablated zones in the blank. The ablated zones may be produced using an ablation tool, such as a laser or a blade. A laser is particularly preferred as the ablation tool as it can allow for a wide variety of ablation profiles and configurations, with minimal adjustment of the laser tool being needed. For example, the laser may be repeatedly passed over a given portion of the blank to iteratively remove different amounts of material, allowing for a very finely controlled ablation profile. This is particularly beneficial if the fine ablated lines are required, with narrow widths. It is possible to accurately control the relative movement of the laser and the blank so as to form any type of pattern with varying removal intensity (“depth”) over the ablation area. 
    
    
     
       The invention will be further described, by way of example only, with reference to the accompanying drawings in which: 
         FIG. 1  depicts a sample portion of a laminar blank for use in determining the spring-back force of the blank; 
         FIG. 2  depicts an apparatus for determining the spring-back force of a blank; 
         FIG. 3  shows a schematic top view of a detail of a first embodiment of a laminar blank for the manufacture of a container in accordance with the present invention; and 
         FIG. 4  shows a schematic top view of a detail of a second embodiment of a laminar blank for the manufacture of a container in accordance with the present invention. 
     
    
    
       FIG. 3  depicts the surface of a cardboard laminar blank  100 , which has a thickness (T) of about 300 micrometres. It comprises a first wall panel  101  for forming a first planar wall of a container, a second wall panel  102  for forming a second planar wall of the container, and a third wall panel  103  for forming a third planar wall of the container. A first edge portion  104  connects the first wall panel  101  and the second wall panel  102 . A second edge portion  105  connects the first wall panel  101  and the third wall panel  103 . The longitudinal direction of the first edge portion  104  is substantially orthogonal to the longitudinal direction of the second edge portion  105 . When the container is assembled from the blank, the first edge portion  104  and the second edge portion  105  form adjacent edges of the container meeting at a junction. 
     The surfaces of the first and the second edge portions  104 ,  105  define a first ablation area A1 and a second ablation area A2, respectively. As shall be explained in more detail below, each ablation area A1, A2 comprises a plurality of ablated zones having a residual thickness less than the thickness (T) of the laminar blank. The ablated zones define areas of weakness, such that the blank  100  can be easily bent when assembling the container and rounded corners of the container can be formed. Each of the ablated zones has a residual thickness of about 20 percent of the thickness T of the blank. The ablated zones are formed in the blank  100  by laser ablation. 
     Each ablation area A1, A2 has a length in the longitudinal direction of the respective edge portion  104 ,  105  and a respective width that extends transversely to the length. 
     The first ablation area A1 comprises a first portion  106  and an end portion  107  extending from the first portion  106  and tapering from a width of the first portion  106  to a point at the junction with the second ablation area A2. 
     The first ablation area A1 comprises a first ablated zone  201  and a second ablated zone  202  which extend in parallel in the longitudinal direction of the first edge portion  104  within the first portion  106  of the ablation area A1. The first and the second ablated zones  201  and  202  taper over the end portion  107  to end at the junction point with the second ablation area A2. 
     The first ablated zone  201  is arranged proximate to the first wall panel  101  and the second ablated zone  202  is arranged proximate to the second wall panel  102 . Further, the first ablation area A1 comprises 4 ablated zones  203 ,  204 ,  205 ,  206  that extend in parallel in the longitudinal direction of the first edge portion  104  within the first portion  106  of the ablation area. 
     The pair of ablated zones formed by the ablated zones  204  and  205  extends in the longitudinal direction of the first edge portion  104  further into part of the tapering end portion  107  of the first ablation area A1. In contrast, the pair of ablated zones  203  and  206  comprises respective slanted sections  2031  and  2061  forming an angle of about 10 degrees with the ablated zones  204  and  205 . As illustrated in  FIG. 3 , the ablated zones  203  and  206  are symmetrical with respect to the pair formed by the ablated zones  204  and  205 . 
     The second ablation area A2 comprises a plurality of ablated zones  300  extending in the longitudinal direction of the second edge portion  105  over the whole length of the second ablation area A2. Thus, a corner portion of the first planar wall panel  101  is delimited by the substantially straight ablated zone  300  of the second ablation area A2 and by the tapered portion of ablated  201  zone of the first ablation area A1. 
       FIG. 4  depicts the surface of another cardboard laminar blank  400 . The cardboard laminar blank  400  will be described below only insofar as it differs from the cardboard laminar blank  100  and parts of the blank  400  having the same features and function of corresponding parts of the laminar blank  100  are referred to, wherever possible by the same numerals. 
     As illustrated in  FIG. 4 , the blank  400  differs from the blank  100  because the second ablation area A2 also comprises a first portion  406  and an end portion  407  extending from the first portion  406  and tapering from a width of the first portion  406  to a point at the junction with the first ablation area A1. The mutual arrangement of the ablated zones  501 ,  502 ,  503 ,  504 ,  505 ,  506  within the second ablation area A2 corresponds to the mutual arrangement of the ablated zones  201 ,  202 ,  203 ,  204 ,  205 ,  206  within the first ablation area A1 as described above. 
     Thus, in the blank  400  a corner portion of the first planar wall panel  101  is delimited by the tapered portion of ablated zone  501  of the second ablation area A2 and by the tapered portion of ablated  201  zone of the first ablation area A1.