CONTAINER HAVING IMPROVED STRENGTH

Abstract

A container for consumer articles is at least partially formed from a laminar blank having an inner surface and an outer surface, and a thickness (T) of from about 100 micrometers to about 350 micrometers. The laminar blank defines a portion of the container that comprises a first planar wall and a second planar wall connected to one another by a first edge portion. The inner surface of the first edge portion comprises one or more ablated lines extending substantially in the longitudinal direction of the first edge portion, each of which is provided as a groove within the blank, having a minimum residual thickness (RT) of from about 15 percent to about 40 percent of the thickness (T) of the laminar blank, and an ablated width (X) as measured transversely to the longitudinal direction of the first edge portion. The laminar blank is folded about the one or more ablated lines such that, for each ablated line, the angle (a) between the outer surface of a first planar portion of the blank adjacent to one side of the ablated line and the outer surface of second planar portion of the blank adjacent to the other side of said ablated line, is within 5 degrees of:

Claims

1. A container for consumer articles, the container being at least partially formed from a laminar blank having an inner surface and an outer surface, and a thickness (T) of from about 100 micrometres to about 350 micrometres, the laminar blank defining a portion of the container that comprises: a first planar wall; and a second planar wall connected to the first planar wall by a first edge portion, wherein the inner surface of the first edge portion comprises one or more ablated lines extending substantially in the longitudinal direction of the first edge portion, wherein each of the one or more ablated lines is provided as a groove within the blank, having a minimum residual thickness (RT) of from about 15 percent to about 40 percent of the thickness (T) of the laminar blank, and an ablated width (X) as measured transversely to the longitudinal direction of the first edge portion, wherein the laminar blank is folded about the one or more ablated lines of the first edge portion such that, for each ablated line, the angle () between the outer surface of a first planar portion of the blank adjacent to one side of the ablated line and the outer surface of second planar portion of the blank adjacent to the other side of said ablated line, is within 5 degrees of: $2.Math.{\tan }^{-1}\left(\frac{X}{2.Math.\left(T-\mathrm{RT}\right)}\right)$

2. A container according to claim 1, wherein the angle () is at least: $2.Math.{\tan }^{-1}\left(\frac{X}{2.Math.\left(T-\mathrm{RT}\right)}\right)$

3. A container according to claim 1, wherein each of the one or more ablated lines is formed as a substantially V-shaped groove within the blank.

4. A container according to claim 1, wherein each of the one or more ablated lines has a minimum residual thickness (RT) of at least about 20 percent of the thickness (T) of the laminar blank.

5. A container according to claim 1, wherein the first edge portion comprises five or less of said ablated lines at any given longitudinal position on its inner surface.

6. A container according to claim 1, wherein the one or more ablated lines extend in parallel in the longitudinal direction of the first edge portion.

7. A container according to claim 1, wherein the laminar blank is a cellulose-fiber-based or wood-fiber-based laminar blank.

8. A container according to claim 1, wherein the ablated width of each of the one or more ablated lines is between about 0.1 millimetres and about 0.5 millimetres.

9. A container according to claim 1, wherein the first planar wall is orthogonal to the second planar wall.

10. A container according to claim 1 comprising: a box portion comprising a box portion front wall, a box portion back wall, first and second box portion side walls, and a box portion bottom wall; and a lid portion depending along a hinge line from a top edge of the box portion, wherein the lid portion is moveable about the hinge line between an open position and a closed position.

11. A container according to claim 11, wherein the first planar wall is the box portion front wall, and the second planar wall is the first box portion side walls.

12. A laminar blank for forming a container for consumer articles, the laminar blank having an inner surface and an outer surface, and a thickness (T) of from about 100 micrometres to about 350 micrometres, the blank comprising: a first wall panel for forming a first planar wall of the container; and a second wall panel for forming a second planar wall of the container, the second wall panel being connected to the first wall panel by a first edge portion; and wherein the inner surface of the first edge portion comprises one or more ablated lines extending substantially in the longitudinal direction of the first edge portion, wherein each of the one or more ablated lines is provided as a groove within the blank, having a minimum residual thickness (RT) of from about 15 percent to about 40 percent of the thickness (T) of the laminar blank, and an ablated width (X) as measured transversely to the longitudinal direction of the first edge portion, and wherein the laminar blank is configured to be folded about the one or more ablated lines of the first edge portion such that when folded, for each ablated line, the angle () between the outer surface of a first planar portion of the blank adjacent to one side of the ablated line and the outer surface of second planar portion of the blank adjacent to the other side of said ablated line, is within 5 degrees of: $2.Math.{\tan }^{-1}\left(\frac{X}{2.Math.\left(T-\mathrm{RT}\right)}\right)$

13. A method of forming a container for consumer articles, the container being at least partially formed from a blank having a thickness (T) of from about 100 micrometres to about 350 micrometres, the method comprising: providing a laminar blank having a thickness (T), the blank comprising: a first wall panel for forming a first planar wall of the container; and a second wall panel for forming a second planar wall of the container, the second wall panel being connected to the first wall panel by a first edge portion; wherein the inner surface of the first edge portion comprises one or more ablated lines extending substantially in the longitudinal direction of the first edge portion, wherein each of the one or more ablated lines is provided as a groove within the blank, having a minimum residual thickness (RT) of from about 15 percent to about 40 percent of the thickness (T) of the laminar blank, and an ablated width (X) as measured transversely to the longitudinal direction of the first edge portion; and folding the first wall panel of the laminar blank relative to the second wall panel, such that, for each ablated line, the angle () between the outer surface of a first planar portion of the blank adjacent to one side of the ablated line and the outer surface of second planar portion of the blank adjacent to the other side of said ablated line, is within 5 degrees of: $2.Math.{\tan }^{-1}\left(\frac{X}{2.Math.\left(T-\mathrm{RT}\right)}\right)$

Description

[0075] The invention will be further described, by way of example only, with reference to the accompanying drawings in which:

[0076] FIG. 1 depicts a perspective view of a container having at least one edge portion according to an embodiment of the present invention;

[0077] FIG. 2 depicts a cross-sectional view of a portion of the laminar blank for forming the container of FIG. 1, shown in an unfolded condition;

[0078] FIG. 3 depicts a cross-sectional view of a portion of the laminar blank for forming the container of FIG. 1, shown in a folded condition;

[0079] As can be appreciated by the skilled person, FIG. 1 shows a container 100 for consumer goods, which can be formed by folding a cardboard or paperboard laminar blank having a thickness (T).

[0080] The container 100 is a substantially rectangular parallelepiped in shape and comprises a box portion 30 and a hinge lid 40 connected to the box portion 30 along a hinge line 50 extending across the back wall of the container 100. The overall size and construction of the box 30 and lid 40 of the container 100 is substantially the same as those of a standard hinge lid cigarette pack. The box portion 30 comprises a box front wall, a box back wall, a box bottom wall, a box left side wall and a box right side wall. The hinge lid 40 comprises a lid front wall, a lid back wall, a lid top wall, a lid left side wall and a lid left side wall. The hinge lid 40 is pivotable about the hinge line 50 between a closed position and an open position. In the closed position, the hinge lid 40 cover an access opening of the container 100 and the walls of the hinge lid 40 form extensions of the corresponding walls of the box portion 30. In the open position, the hinge lid 40 pivots about the hinge line 50 to project backwardly from the box portion 30 and the access opening at the top end of the box portion 30 be fully uncovered. The box portion 30 and the hinge lid 40 may be formed together from a single laminar blank having a thickness T. The container may be assembled from the laminar blank and filled using standard apparatus.

[0081] The container comprises a first planar wall 4, which in FIG. 1 is a side wall of the box portion 30. The container also comprises a second planar wall 8, which in FIG. 1 is the front wall of the box portion 30. The side wall 4 and the front wall 8 are connected to each other by a first edge portion 20, which is shown in FIG. 1 as a bevelled edge portion 20. Although not visible from the perspective view in FIG. 1, the inner surface of the bevelled edge portion 20 comprises first and second ablation lines that each define respective turning points 22 and 24 of the bevelled edge portion, when the container 100 is assembled. The turning points 22 and 24 extend in parallel with one another in the longitudinal direction of the bevelled edge portion 20, to thereby define a single rectangular facet 6 of the bevelled edge portion 20.

[0082] The laminar blank therefore transitions from the side wall 4 to the facet 6 by an angle (22) about the first ablation line defining turning point 22. The first ablation line should therefore be designed to have a minimum residual thickness (RT) of from about 15 percent to about 40 percent of the thickness (T) of the laminar blank, and an ablated width (X) as measured transversely to the longitudinal direction of the first edge portion, such that the angle (22) is within five degrees of:

[00006]$2.Math.{\tan }^{-1}\left(\frac{X}{2.Math.\left(T-\mathrm{RT}\right)}\right)$

[0083] Similarly, the laminar blank transitions from the facet 6 to the front wall 8 by an angle (24) about the second ablation line defining turning point 24. The second ablation line should therefore be designed to have a minimum residual thickness (RT) of from about 15 percent to about 40 percent of the thickness (T) of the laminar blank, and an ablated width (X) as measured transversely to the longitudinal direction of the first edge portion, such that the angle (24) is within five degrees of:

[00007]$2.Math.{\tan }^{-1}\left(\frac{X}{2.Math.\left(T-\mathrm{RT}\right)}\right)$

[0084] This can be best appreciated from FIGS. 2 and 3 which show cross sectional views of the first edge portion 20 in an unfolded and folded condition respectively. In particular, FIG. 2 shows the laminar blank in an unfolded substantially flat condition, with the first ablation line 220 and the second ablation line 240 being substantially V-shaped in their cross-sectional profile. FIG. 3 shows the blank in a folded condition, whereby the side walls of each ablation groove's 240, 220 sidewalls have been brought together to abut one another. The blank has been folded such that an angle 24 exists between the outer surface of the front wall 8 and the facet 6, and an angle 22 exists between the outer surface of the side wall 4 and the facet 6. As a consequence of the ablation line designs, and fold angles 24 and 22, the bevelled edge portion 20 can have an improved strength and be less vulnerable to local deformation.

[0085] FIGS. 2 and 3 are provided purely for illustrative purposes, and it will be appreciated that are they are not necessarily schematically accurate or to scale.