GB2321236A

GB2321236A - Cartons

Info

Publication number: GB2321236A
Application number: GB9800690A
Authority: GB
Inventors: Giorgio Damiano; E Keogh; Philip Wright
Original assignee: Colpac Ltd
Current assignee: Colpac Ltd
Priority date: 1997-01-15
Filing date: 1998-01-14
Publication date: 1998-07-22
Also published as: GB9800690D0; GB9700704D0

Abstract

A blank for producing a carton has a rectangular rear panel (1). A pair of side panels (4) are respectively connected to one pair of parallel sides (2), and top and bottom panels (5, 6) are respectively connected to the other pair of parallel sides (3) of the rear panel (1). A closure flap (12, 14) is attached to edge (10) opposite the rear panel (1) of each of the side (4), top and bottom panels (5, 6), and a generally triangular blank portion (7) connects each side panel side edge (25) to the adjacent side edge (26) of the adjoining top or bottom panel (5, 6). The side panel side edges (25) are directed at oblique angles to the first pair of parallel sides (2) so that, when folded to form a carton, the top and bottom panel (5, 6) lateral edges (25, 26) diverge away from the rear panel to enable effective stacking. The blank portions (7) fold onto the top/bottom panels (5, 6) to retain the folded shape of the carton.

Description

PACKAGING This invention relates to packaging and in particular the invention is concemed with cartons which can be formed by folding a shaped blank of paper, paperboard or cardboard.

For ease and economy of transportation to customers packaging cartons need to be deliverable in flat form or in stacks, and the cartons must be designed to facilitate erection, if necessary, by the customer as well as their filing with products to be packaged and subsequent closure. Furthermore, there is a desire for the carton to be convenient for the eventual customers purchasing the packaged products to open.

In the packaging industry, and especially for use with food products there exists a need for a carton of generally triangular configuration, e.g. suitable for packaging sandwiches, which can meet all the foregoing demands.

According to one aspect of the present invention, whose scope is defined in the appended claims, there is provided a carton folded from a blank and comprising a rear panel having a rectangular shape with a first pair of opposed sides and a second pair of opposed sides, a pair of side panels integrally connected to the rear panel at the first pair of opposed sides, the side panels having side edges which extend at oblique angles to said first pair of opposed sides, top and bottom panels integrally connected to the rear panel at said second pair of opposed sides, the top and bottom panels being coplanar with the side edges of the side panels, the side, top and bottom panels having substantially coplanar front edges, at least one of the front edges having a closure flap for closing the opening defined by said front edges, and the side panels being secured to the top and bottom panels at each of the side edges by a tongue integral with one panel and folded onto and secured to the adjoining panel.

In the preferred carton of the invention the front face defined by the front edges of the top, bottom and side panels is substantially parallel to the rear panel. One side panel has a closure flap integrally attached to the front edge thereof and adapted to cover substantially the entire front opening. This closure flap is equipped with a tab which is engageable in a slot to secure the closure flap in the closed condition. The top and bottom panels have lateral edges which diverge in the direction away from the rear panel so that the interior of the carton tapers towards the rear panel, which enables cartons to be efficiently stacked together for bulk transportation with their closure flaps open and the cartons ready to be filled. For ease of manufacture the side panels are secured to the top and bottom panels by generally triangular portions, each of which is connected, along side edges which meet at the rear panel, to a side panel and the adjoining top or bottom panel, the generally triangular portion being folded in half to form a tongue which is folded onto one of the panels, preferably on to the outer surface of the top or bottom panel, and fastened thereto by adhesive.

In an advantageous development of the invention, each of the other side panel, the top and the bottom panels also has a closure flap integrally attached to its front edge. These additional closure flaps are arranged to be covered by the first mentioned closure flap when it is in its closed position and may have adhesive such as double sided tape applied to their surfaces which retain the first mentioned flap in its closed position.

According to another aspect of the present invention there is provided a blank for producing a carton as described above, the blank comprising a rear panel delimited by first and second pairs of opposed parallel fold lines, a pair of side panels respectively connected to the rear panel along said first pair of fold lines, the side panels having side edges directed at oblique angles to the first pair of fold lines, top and bottom panels respectively connected to the rear panel at the second pair of opposed parallel fold lines, the edge of at least one of said side, top and bottom panels opposite the rear panel having a closure flap attached thereto, and a generally triangular blank portion disposed between each side edge of the side panels and the adjacent edge of the adjoining top or bottom panel each generally triangular portion being connected to at least one of the associated side panels and adjoining top or bottom panel.

A more complete understanding of the invention will be gained from the following detailed description of a preferred embodiment, reference being made to the accompanying drawings in which: Figure 1 is a plan view of a carton blank according to the invention; Figure 2 is a rear elevation of a carton assembled from the blank of Figure 1; Figure 3 is a rear perspective view of the carton; Figure 4 is a front perspective view of the carton in a closed condition; Figure 5 is an isometric view showing the carton at an intermediate stage during assembly; Figure 6 is an isometric view showing the carton assembled but open for stacking with other cartons of the same construction; and Figure 7 is an isometric view of the assembled carton with adhesive applied to aid closure.

The carton blank shown in Figure 1 may consist of paper, paperboard or cardboard or any of these materials laminated with a foil of other material, e.g.

plastics. The blank includes a generally central rear panel 1 which is rectangular (for the purposes of the present specification the word "rectangular" should be understood to include square), with a pair of first parallel sides 2 defined by fold lines and a pair of second parallel sides 3 also defined by fold lines. Attached to the rear panel along the fold lines 2 are side panels 4 of essentially identical shape and attached to the rear panel along the fold lines 3 are top and bottom panels 5, 6 also of substantially identical shape. The edges of the panels 4, 5, 6 remote from the rear panel are arranged to lie in a common plane and to define a front face opening when the carton is assembled from the blank as will become clear. The side edges ofthe side panels 4 are defined by fold lines 25, these fold lines being directed at oblique angles to the fold lines 2 so that the panels 4 have the shape of a trapezium. Connected between the fold lines 25 and the adjacent edges of the top and bottom panels, along which fold lines 26 extend, are blank portions 7 which can conveniently be described as generally triangular since the shape of their free edges 8 remote from the apices defined at the corners of the rear panel 1 is unimportant and not crucial to the invention. Each of the portions 7 is bisected by a fold line 9 extending from the apex to the free edge 8, as shown the part between the bisecting fold 9 and the side panel 4 being larger than the part between the bisecting fold line 9 and the top/bottom panel 5,6 although this is not an essential requirement of the invention. Attached to the edges of the side, top and bottom panels 4, 5,6 remote from the rear panel, and delimited from the panels by fold lines 10 are closure flaps 12, a main closure flap 14 being attached to one of the side panels and having a securing tab 15 which is engageable in a slot 16 for securing the closure panel in a closed position. The lateral edges of the top and bottom panels 5,6 diverge in the direction away from the rear panel so that the side panels 4 in the assembled carton converge inwardly towards the rear panel enabling close stacking of cartons when they are assembled with their closure flaps open as shown in Figure 6. The blank can be cut to shape and provided with the fold lines using conventional carton manufacturing techniques. Glue is applied to the blank in the areas of the top and bottom panels shown shaded in Figure 1 and the carton is erected by folding the side, top and bottom panels 4,5,6 generally towards each other about the fold lines 2,3. In this folding process the portions 7 become folded in half about their bisecting fold lines 9, and the top and bottom panels 5, 6 are brought to lie in common planes with the adjacent side edges of the side panels 4. This is the condition illustrated in Figure 5. The tongues formed by the folded portions 7 are then folded onto the adjoining top and bottom panels to which they become fastened by the glue, whereby the carton is retained in the assembled condition of Figure 6. The free edge 8 of the portions 7 is so shaped that the part of each portion which is outermost in the assembled cartons extends beyond the inner part of the same portion so that both parts become glued direction to the top or bottom wall. As mentioned above, several such assembled cartons can be nested together in a stack convenient for transportation and storage.

When a carton is required for use it can be easily separated from the stack, and after the product to be packaged has been introduced through the open front, the three small closure flaps 12 are folded inwardly and covered by the main closure flap 14 which is folded to cover the front face opening and is secured in this closed position by insertion of the tab 15 into the slot 16.

Instead of using a tab and slot arrangement to retain the main closure flap 14 in the closed position, the three small closure flaps 12 may have adhesive 30, such as double sided tape, applied to their outwardly facing surfaces as shown in Figure 7. This adhesive, upon closure of the main flap 14, adheres to the inner surface of the flap 14 and provides an airtight seal between the main flap 14 and the small flaps 12. The adhesive may, in this case, be applied to the small closure flaps 12 by machine during manufacture of the blanks. Of course the adhesive could alternatively be applied to the main flap 14.

The carton may, in fact, be provided with both an adhesive seal for the closure flap 14 and the tab 15 and slot 16 arrangement, so that once the airtight seal produced by the adhesive has been broken, the flap can still be reclosed by insertion ofthe tab 15 into the slot 16.

In the illustrated embodiment the closure flap 14 is shown to have windows which enable the contents of the carton to be viewed, but such windows are not essential and can be omitted if preferred. Other modifications are also possible without departing from the scope of the invention. For example the tongues formed by the folded portions 7 could be folded onto and glued to the side panels 4, or they could be folded inwardly to be secured to the inner surfaces of the top and bottom panels 5, or the side panels 4.

Claims

1. A carton folded from a blank and comprising a rear panel having a rectangular shape with a first pair of opposed sides and a second pair of opposed sides, a pair of side panels integrally connected to the rear panel at the first pair of opposed sides, the side panels having side edges which extend at oblique angles to said first pair of opposed sides, top and bottom panels integrally connected to the rear panel at said second pair of opposed sides, the top and bottom panels being coplanar with the side edges of the side panels, the side, top and bottom panels having substantially coplanar front edges, at least one of which front edges having a closure flap for closing the opening defined by said front edges, and the side panels being secured to the top and bottom panels at each of the side edges by a tongue integral with one panel and folded onto and secured to the adjoining panel.

2. A carton as claimed in claim 1, wherein the substantially coplanar front edges of the side, top and bottom panels each have a closure flap for closing the opening defined by said front edges.

3. A carton as claimed in claim 2, wherein one of the closure flaps is adapted to close over the other closure flaps and to cover substantially the entire front opening.

4. A carton as claimed in claim 3, wherein for securing said one flap in a closed position, at least one of the closure flaps has adhesive on a surface thereof.

5. A carton as claimed in claim 4, wherein each of said other closure flaps has adhesive thereon.

6. A carton as claimed in claim 4 or 5, wherein the adhesive is double sided tape.

7. A carton as claimed in claim 4, 5 or 6, wherein the adhesive forms an airtight seal between the said one closure flap and the said other closure flap.

8. A carton as claimed in any of claims 1 to 7, wherein the said one closure flap has a tab on one free edge which is engageable in a slot to secure the said one closure flap in the closed position.

9. A carton as claimed in any of the preceding claims, wherein the top and bottom panels have lateral edges which diverge in the direction away from the rear panel such that the interior of the carton tapers towards the rear panel, thereby facilitating stacking of the open cartons.

10. A carton as claimed in any of the preceding claims, wherein the side panels are secured to the top and bottom panels by generally triangular portions, each of which is connected, along side edges which meet at the rear panel, to at least one of a side panel and the adjacent top or bottom panel.

11. A carton as claimed in claim 10, wherein each generally triangular portion forms a tongue which is folded on to one of the panels and fastened thereto by adhesive.

12. A carton as claimed in claim 11, wherein the tongues are folded on to the outer surfaces of the top and bottom panels as appropriate.

13. A carton as claimed in claim 11 or claim 12, wherein each generally triangular portion is connected to both a side panel and the adjacent top or bottom panel and is folded in half to form the tongue.

14. A blank for producing a carton as claimed in any of the preceding claims, the blank comprising a rear panel delimited by first and second pairs of opposed parallel fold lines, a pair of side panels respectively connected to the rear panel along said first pair of fold lines, the side panels having side edges directed at oblique angles to the first pair of fold lines, top and bottom panels respectively connected to the rear panel at the second pair of opposed parallel fold lines, the edge of at least one of said side, top and bottom panels opposite the rear panel having a closure flap attached thereto, and a generally triangular blank portion disposed between each side edge of the side panels and the adjacent edge of the adjoining top or bottom panel each generally triangular portion being connected to at least one of the associated side panels and adjoining top or bottom panel.

15. A blank as claimed in claim 14, wherein the side edges of the side panels are defined by fold lines.

16. A blank as claimed in claim 15, wherein each generally triangular blank portion is connected between a side edge fold line of a side panel and a fold line extending along the adjacent edge of the adjoining top or bottom panel, and each generally triangular blank portion is substantially bisected by a fold line directed away from a respective corner of the rear panel.

17. A blank as claimed in any of claims 14 to 16, wherein the or one of the closure flaps has a tab connected to a free edge thereof for engagement in a slot for retaining the closure flap in a closed position in the erected carton.

18. A blank as claimed in any of claims 14 to 17, wherein the edge of each said side, top and bottom panels opposite the rear panel has a closure flap attached thereto.

19. A blank as claimed in claim 18, wherein at least one of said closure panels has adhesive applied to it.

20. A carton folded from a blank substantially as herein described with reference to the accompanying drawings.

21. A blank for producing a carton substantially as herein described with reference to the accompanying drawings.