FIELD OF THE INVENTION

The present invention relates to improvements in lidded packs and components thereof, and to the use of inwardly turned flaps of a base component of a lidded pack so as to ensure better bonding during a lidding process.

BACKGROUND TO THE INVENTION

Figures 1A, B and 1C show respectively (i) a base blank, (ii) a base erected using adhesive (eg. hot melt adhesive) from the blank to define a base component able to be lidded, and a (iii) lid provided by a lidding blank, the lid having flanges to be hot melt or otherwise adhesively affixed to the exterior of each wall of component B.

Such a prior art arrangement as shown in Figures A to C is a standard machine erect chilled meat pack used in Australasia.

A difficulty sometimes encountered with such a prior art arrangement is the bowing (particularly inward) that might occur at or adjacent the top of one or more of the walls when a lid as shown is being adhesively or hot melt glue attached over the filled base component.

This occurs particularly when there is not filling sufficient to resist such exteriorly applied pressure during the lidding process. The problem is typically worse on the longer walls of the container.

In this specification where reference has been made to patent specifications, other external documents, or other sources of information, this is generally for the purpose of providing a context for discussing the features of the invention. Unless specifically stated otherwise, reference to such external documents is not to be construed as an admission that such documents, or such sources of information, in any jurisdiction, are prior art, or form part of the common general knowledge in the art. It is an object of the present invention to provide a base component (irrespectively of what its content is to be) that overcomes such a difficulty or reduces that difficulty. It is a further or alternative object of the present invention to enhance the bond integrity between a base component and a lid component in lidded packs (including in chilled meat packs) of the kind previously described or at least to provide the public and/ or industry with a useful choice.

SUMMARY OF THE INVENTION

In an aspect the invention broadly consists in a lidded pack

A lidded pack comprising:

a base component of a square or rectangular plan periphery erected from one or more blank(s) to define a base panel two side walls and two end walls,

an opposed pair of side walls having a flap extension at its top, and

a lid component provided by a blank to define a lidding panel and four peripheral lidding flaps; wherein

the flap extensions increasing the resistance of the side walls to deformation under a pressure used to adhesively engage the lidding flaps to the exterior of the side walls.

According to another aspect said base component is rectangular and the side walls are the longer opposed pair of walls and includes said flap extensions.

According to another aspect each of the side walls and the ends walls includes a said flap extension. According to another aspect each said flap extension turns inwards along a fold line at or toward the top of a respective wall from which the flap extension is provided.

According to another aspect said extension flaps are substantially horizontal after the lidded pack has been adhesively closed.

According to another aspect said walls are perforated intermittently along said foldline, such than when said extension flap is folded inwardly, a transition between said wall and said flap is, alternating along the foldline between: i) a hinged region,

ii) a perforated region.

According to another aspect said perforated region, a transverse cut edge of said wall projects upwardly through the thickness of the wall and presents an upper surface substantially flush with an upper surface of said extension flap.

According to another aspect the flap extensions are each (optionally) mitre ended. According to another aspect the lid component flaps are each (optionally) mitre ended.

According to another aspect the side walls are of single panel form yet have end flaps, each of which is positioned (and preferably adhered) inwardly of the end wall panels thereby to define twin end flap reinforced end walls.

According to another aspect the end flaps do not overlap in the end wall constructions.

According to another aspect said lid component is adhesively fixed to said base component, by adhesive between interior surfaces of said lidding flaps and exterior surfaces of respective base component walls.

According to another aspect said base component and said lid component are of a corrugated paperboard. According to another aspect said corrugated paperboard on at least one of said base or said lid is of a double cushion corrugated paperboard.

In another aspect the invention broadly consists in a method of lidding a container comprising:

providing the lidded pack of any one of claims 1 to 14, with the extension flaps folded at least partially inwardly,

applying adhesive to at least one of the interior surfaces of said lidding flaps and exterior surfaces of respective base component walls, placing said lid atop said base component,

folding said lidding flaps downwards over the base component and applying a lateral pressure to press said interior surfaces of said lidding flaps against said exterior surfaces of respective base component wall.

According to another aspect said adhesive is a hot melt adhesive.

According to another aspect said adhesive is applied to the interior surfaces of said lidding flaps.

According to another aspect said step of providing the lidded pack with the extension flaps folded at least partially inwardly, comprises folding the extension flaps to be substantially horizontal. In a further aspect the present invention is a base component, or blank therefore, of, or suitable for, a lidded pack as claimed in any one of the previous claims.

In still a further aspect the invention is base component substantially as herein described and with reference to Figure 3.

In yet another aspect the invention is a blank substantially herein described and with reference to Figure 2.

In yet another aspect the invention is a method of lidding a container substantially as herein described and with reference to any one or more of Figures 2-8.

Definitions or terms or phrases.

As used herein the term "blank" refers to any sheet material appropriate for one or other of the components. Preferably the blank is a corrugated board (eg. with paper liner on the outside of a single layer or multiple layer flute medium cushion). In other forms it can be of solid paper board construction. In still other embodiments a liner can be provided on one side or the other, or both, that enhances waterproofness and/ or insulation characteristics (whether that be a coating of a wax, a plastics film, metallised film or other).

The term "comprising" as used in this specification and claims means "consisting at least in part of. When interpreting each statement in this specification and claims that includes the term "comprising", features other than that or those prefaced by the term may also be present. Related terms such as "comprise" and "comprises" are to be interpreted in the same manner. As used herein the term "and/ or" means "and" or "or", or both.

As used herein the term "(s)" following a noun includes, as might be appropriate, the singular or plural forms of that noun.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention will be described by way of example only and with reference to the drawings, in which:

Figure 1A to 1C are as previously defined and relate to prior art forms of containers. Figure 2 is a preferred blank of the base component.

Figure 3 is a base component erected using adhesive from the blank of Figure 2.

Figure 4 is a preferred blank of the lid component.

Figure 5 shows a similar lid component as shown in Figure C but which is better able to be bonded by any adhesive (hot glue or otherwise) interposed (usually by application to the lidding flaps) between a lidding flap and the exterior panel of the walls of the component of Figure 3.

Figure 6 is an assembly view of the lidded back showing a lid being brought onto a base component.

Figure 7 is a perspective view of the lidded pack with lid adhesively fixed to the base component.

Figure 8 is a close-up view of the base component showing the foldline perforation detail.

Figure 9 is a view of an alternative pack and blank. DE AILED DESCRIPTION OF PREFERRED EMBODIMENTS

The blank for the base component of the present invention preferably of a suitable corrugated paper board but not necessarily so. Preferably there is a rectangular base panel 1, opposed end wall panels 2, opposed side wall panels 3, and side wall extension flaps 4.

Each of the side wall panels 3 has a flap extension 5 at its top. These flap extensions are shown as 5 and preferably are each mitre ended. In this embodiment, only the longer side walls include flap extensions 5. However, it will be appreciated that an alternative form is possible as shown in Figure 9. In this alternative embodiment, the end wall panels 2 also include flap extensions 6 at their tops.

Preferably the container has a flute run direction as indicated by arrow 20. This provides improved vertical load bearing capability in the side walls 3. In other

embodiments, the flute run direction may be perpendicular to that indicated as preferred.

When erected, the base component is as shown with each of the extension flaps 5 (and/ or 6) turned upwardly. In the case of the side walls 3, the inturned flap is from a single panel providing the wall. In the case of the end walls, the flap 6 is from that panel 2 that is reinforced inwardly by a pair of side wall flap extensions 4.

With reference to Figures 4 and 5, a blank for a lid, and the lid, are shown respectively. The lid comprises a panel 7 that is sized and shaped to compliment the base of the container 1. On each peripheral wall of the lid panel 7 are lidding flaps 9 and 10. Preferably the ends of the lidding flaps 9 and 10 are mitred.

Figure 6 shows a lid being positioned over a base component ready for adhesively securing. During this process, the lid is placed over top the open topped container (a container having the flap extensions turned inwardly). With the lid placed on top of the container, the lidding flaps 9, 10 are adhesively secured to the outer surfaces of the end walls and side walls 2, 3 respectively. Preferably, the adhesive is of a hot melt type and is preferably applied to the inner surface of the lidding flaps 9, 10, immediately before fixing.

In order to ensure that adequate bonding occurs, is preferred to apply a lateral (inwards) force to push the lidding flaps 9, 10, onto the respective container walls. Figure 7 shows the completed and, sealed container of the present invention.

It is found that a base component as depicted in Figure 3, and any suitable variation of it, is better able (when a lid is glued on) to resist any tendency for the walls (3, or 2) to bow inwardly owing to an externally applied sealing pressure onto the flaps 9 and 0. This resistance arises from a flap 5 (or 6), during the lidding process being inturned almost horizontally to support its foldline against bowing. This better enables the flap 9 and 0 respectively to be adhered by a suitable interposed hot melt glue (usually applied on the lid flaps) against the outside of a wall panel 3 and a wall panel 2.

The box type base component with the novel features, specifically the additional flaps 5 and/ or 6 along the top edge of the box serve to reinforce these top edges laterally so that the lid with hot-melt glue applied can be mechanically placed atop the box, and its lid flaps folded by force against the sides of the box to seal the entire package. These minor box flaps provide resistance as the lid flaps are pressed against the box sides, allowing the hot-melt adhesive between the two to be pressed flat and thin, and hence cool, solidify and form a bond.

With reference to Figure 8, a preferred form of folding configuration of the flap extensions 5, 6 will be described. The fold transition at the top of the respective walls between the flap extension and wall preferably comprises an intermittent perforation arrangement. In particular, the fold transition preferably alternates between hinged regions 12 and perforated regions 3. The perforations 3 are preferably shaped with a substantially straight line central portion and have two short (approximately

perpendicular) cuts at each end. That is, the perforation is of a flat bottomed and short sided "U" shape. The length of the short side is preferably approximately the thickness of the corrugated medium from which the container base is formed.

When folded over along the fold transition , so that the flap extensions 5 (or 6) are turned inwardly, a transverse cut edge 4 of the wall projects through the perforation and presents substantially flush with the upper face of the extension flap 5, 6. This feature provides one or more of the following advantages:

" A line of weakness upon which the fold transition folds accurately.

^■ Upwardly facing transverse cut edges 4 effective at bearing vertical loads.

^■ The projection of the cut edges through thickness of the wall helps keep the extension flap in position when folded inwardly.

^■ The hinged regions 2 provide firm connection between the flap

extensions 5, 6 and the respective container wall.

Preferred use of the containers is with for example chilled meat. However other produce can fill such a base component and be lidded (eg. fish). The foregoing description of the invention includes preferred forms thereof.

Modifications may be made thereto without departing from the scope of the invention.