GB2539868A

GB2539868A - Improvements in packages

Info

Publication number: GB2539868A
Application number: GB1505011.5A
Authority: GB
Inventors: Avrial Yauk Fernandes Kate; Findlay Graeme; Blyth Simon; Oliver Olivercort Dominic; Wahlgren Pontus
Original assignee: Kraft Foods R&D Inc USA
Current assignee: Kraft Foods R&D Inc USA
Priority date: 2015-03-25
Filing date: 2015-03-25
Publication date: 2017-01-04
Also published as: GB201505011D0; WO2016151355A1

Abstract

A package 10 includes at least one side wall defining an interior, and contains a product. The package is formed from a multi-ply material which includes an inner layer 11 peelably adhered to an outer layer 12. Several lines of weakness 25 are provided in the outer layer, spaced apart along a first direction. Several corresponding longitudinally spaced apart lines of weakness 26 are provided in the inner layer. Each line of weakness extends in a second direction which is transverse to the first direction. The lines of weakness in the inner layer are offset in the first direction to the lines of weakness in the second layer, thereby enabling the side wall to be separable to form two package sections. Each section includes an inner layer flap 35 and outer layer flap 36, which allow the package sections to be reclosed. An advantage of the invention is a consumer may separate portions of the product and package and reclose the package after removal of the portions.

Description

IMPROVEMENTS IN PACKAGES

The present invention relates to improvements in reclosable packages suitable for a comestible product, such as a chocolate bar, and in particular to reclosable packages which allow a consumer to separate portions of the product and the package, and to reclose the package after removal of the portion(s).

Historically many confectionery bars, such as chocolate, were wrapped in a first layer of aluminium foil, which was covered by a printed paper sleeve carrying brand and product information. Although the wrappers were easy to open, this necessitated a two step packaging process, which was time consuming and costly and the integrity of the materials used, which were prone to tearing, were difficult to maintain, especially after opening.

Nowadays flow-wrapping is a more convenient and common packaging method used, especially in the consumables industry, as it is can be used for forming sealed flow wraps and bags. The wrapping material may be slit into sheets which are formed into tubes, an end of which is sealed using heat and/or pressure. The product to be packaged is then fed into the open mouth of the tube and the mouth sealed. Alternatively, the wrapping material may be slit into multiple sheets, each of which is folded and the overlying side edges sealed together before the partially formed package is filled via the remaining open mouth. The top edges are then sealed together. The manufacturing process is carried out using horizontal/vertical form, fill, and seal machines, known as VFFS and HFFS machines. Example of such machines are the Bosch Sigpack HSM which is a High Speed single line machine, or the Ctpack OTEM low speed multilane flow wrapper.

The materials used in flow wrapping are commonly any one of a number of known paper based foil-based and plastic based materials. Laminated polymeric films are particularly suitable for packaging comestible products as they are not only thin and flexible, but also tough and durable and may be relatively impermeable to air and moisture. These materials can also be conveniently printed with brand and product information. EP-A-1288139 describes a package for packing generally blocked shaped food products, such as chocolate, using a VFFS machine and forms a fin seal along the length of the package which is convenient to open.

Thus flow-wrapping is particularly suitable for the packaging of perishable comestibles, with the package being hermetically sealed for freshness during the flow wrapping process. Such hermetically sealed packages often contain more than one serving portion of the product, which provides better value for money to consumers. Therefore, in order to maintain freshness, it is beneficial if the package can be resealed.

Various methods of resealing comestible packages are in use, the most common being by providing a resealable tab/label with the package, which can be used to secure the package into a closed position following its initial opening. US-A-2002/0114541 discloses a package with a resealable tab which is integral to the package, being formed from a portion of the outer layer of the packaging laminate . ΕΡ-Ά-1714895 describes a reclosable package having a tamper evident feature which gives a visual indication to the consumer that the package is not in the initial unopened state, but in a closed state. ΕΡ-Ά-1139106 further develops the reclosability of a package and describes a package which is easy to open and reclose. This is achieved by using a cold seal applied between the first and second sealing portions which has a bonding force provides a cohesive split when the package is opened and the seal is broken. As a result the seal partly adheres to a first sealing portion and partly adhered to a second sealing portion. When these two sealing portions are brought back together it enables the package to be reclosed.

Resealing methods such as this allow packages to be resealed multiple times. However, this inevitably results in a decline in the freshness of the product. Additionally, such methods only allow incremental consumption of a food product, i.e. each time the package is opened a portion (or a number of portions) is removed and consumed, with the remaining portions being left in the single package. It is not possible to easily split the package into individual serving portions, to be eaten by multiple people or by one person on multiple occasions, while retaining the optimal product freshness without using additional wrapping materials .

In a recent development to try to provide multiple portions in a single package, Kraft Foods have produced a line of Milka*™* chocolate bar which is divided into two portions, but is packaged in a single package which is sealed between the two portions. The package is provided with perforations along the seal to enable it to be divided to give two separate sealed portions.

At the opposite end of the spectrum from large 'value' packages, comestibles are often also packaged according to the recommended individual portion size of a product. This type of packaging results in the best freshness of the product. However, such a packaging system is more expensive, with the uplift in cost necessarily transferring to the consumer.

Accordingly there is therefore provided a package having at least one side wall defining an interior of the package for receiving a product, said package being formed from a multi-ply material comprising at least an inner layer peelably adhered to an outer layer wherein a plurality of lines of weakness are provided in the outer layer spaced apart along a first direction of the package and a corresponding plurality of longitudinally spaced apart lines of weakness are provided in the inner layer, each line of weakness extending in a second direction which is generally transverse to the first direction, the lines of weakness in the inner layer being offset in the first direction to the corresponding lines of weakness in the outer layer, such that the side wall is separable along a corresponding pair of lines of weakness in the inner and outer layer to form two package sections, each package section having an inner layer flap and an outer layer flap formed by the separation of the inner and outer layers providing means for reclosing the package sections

There is further provided a method of packaging a material in a multi-ply material comprising at least an inner layer peelably adhered to an outer layer by means of a resealable pressure sensitive adhesive, said method comprising the steps of forming lines of weakness in the outer layer spaced apart along a first direction; forming a corresponding plurality of spaced apart lines of weakness in the inner layer, each line of weakness extending in a second direction which is substantially transverse to the first direction, the lines of weakness in the inner layer being offset in the first direction to the corresponding lines of weakness in the outer layer; providing a product to be packaged and enclosing the product in the packaging material.

The package described herein is therefore highly advantageous in that it permits reclosure after a portion of the product has been removed whilst at the same time enabling one or more separated portions of the product to be individually reclosed in separated sections of the package achieved without the need for material beyond what is supplied by the package. This means that a larger bar of product can be divided into smaller portions for consumption by different people, or over a period of time.

Advantageously only one edge of the product is exposed and, as the reclosing process is quick, the exposure time can be kept to a minimum. Furthermore, the size of the portions to be broken off and rewrapped may be selected by the consumer and may be varied.

The package further permits sharing of the product without the need for anyone to touch a portion other than the person who consumes it, as the portion can remain covered by the separated section of the package until extracted by the consumer. A preferred embodiment of the package will now be described, by way of example only, with reference to the accompanying drawings in which :-

Figure 1 is a plan view of the front of the package described herein;

Figure 2 is a plan view of the back of the package of Figure 1;

Figure 3 is a cross-sectional side elevation of the package of Figures 1 and 2;

Figure 4a is a plan view of the front of the package of Figure 1 with a portion removed;

Figure 4b is a perspective view of the package of Figure 4a showing a chocolate bar inside the package;

Figure 5 is a plan view of the back of the package of Figure 4; and

Figure 6 is a plan view of the removed portion. A preferred embodiment of the package 10 is formed from a piece of multi-ply material, such as a laminate, comprising at least two layers (plies), namely an inner layer 11 and an outer layer 12, which can be delaminated or peeled apart by hand. The layers 11,12 are preferably adhered to each other by means of a reclosable pressure sensitive adhesive. The adhesive is selected to provide a peel force which is light enough to allow a consumer to easily separate the layers 11,12 whilst being strong enough to maintain the integrity of the package 10 during handling. It also enables the layers 11,12, or portions thereof, to be re-adhered as described below. The preferred adhesive is provided on the inner and outer layer 11,12 and may be provided in a pattern. It is preferably a cold seal as described in EP-A-1939106 in which the bonding force of the adhesive to each of the layers 11,12 is greater than the bonding force within the adhesive. This causes the adhesive to separate as the layers 11,12 are peeled apart. As a result the adhesive partly adheres to the inner layer 11 and partly to the outer layer 12. This is known as a "cohesive split" and is advantageous in that the adhesive material will stay on both layers 11,12 and will not leave one of the layers 11,12 with no adhesive after the layers 11,12 have been separated.

The initial separating force between the inner and outer layers 11,12 is preferably 2.5 to 4 N/15 mm and preferably 2 N/15 mm. The opening force after reclosure is preferably in the range of 0.5 to 2 N/15 mm and more preferably in the range of 1 to 1.5 N/mm as is also described in EP-A-1939106 which describes how these forces can be measured. These values are effective for avoiding accidental delamination of the layers 11,12 whilst allowing the package to be used as preferred.

To improve the cohesive split, the layers 11,12 may first be coated with an acrylic coating or a primer. The coating may have a thickness of 0.5 to 1.5 g/m^, preferably about 0.9 g/m^. A suitable adhesive may be a natural latex adhesive. It may be, as described in EP-A-1939106, a hard cold seal (as opposed to a conventional soft cold seal). Hard cold seals contain less rubber and more polymers or copolymers, particularly acrylic polymers or copolymers. Preferably the adhesive has a polymer/copolymer content of above 30%, preferably above 50% and even more preferably above 70%. It has been found that a cold seal containing at least one acrylic polymer or copolymer provides a good reclosability. It is also preferred that the cold seal contains at least one styrene acrylic polymer or copolymer, and preferably two different kinds thereof. In particular, a softer styrene acrylic polymer or copolymer together with rubber, particularly a natural latex based rubber, provides good initial sealing. The adhesive should be applied in appropriate amounts, which may be in the region of 3 to 5, and g/m^ on each layer 11,12 and more preferably 3.5 to 4.9 g/m^

The layers 11,12 may be of the same material or different materials. The material(s) is/are ideally selected to be thin and flexible, which makes them easier to handle and suitable for use in a flow wrapping process, yet tough and durable, to provide good protection for the product contained therein. Ideally the material of at least one of the layers 11,12 is relatively air and moisture impermeable, which helps to prevent degradation of the wrapped product. Examples of suitable materials are waxed paper, waxed glassine, cellulose film (cellulose acetate), polyvinylchloride, oriented high density polyethylene or polypropylene, poly active acids or polyacids. The total thickness of the two layers 11,12 is preferably 60 to 70 microns. Each layer preferably has the same thickness, but they may be different.

In the illustrated embodiment of the package 10, the package 10 has side walls comprising a front wall 13 (see Figure 1) and a back wall 14 (see Figure 2) which is on opposing edges 15, 16 opposing ends 17,18 to define the package interior for receiving a product. The package 10 can be used for any type of product and is particularly suitable for comestible products in tablet block or bar form such as a chocolate or other types of confectionary bar.

The package 10 is preferably formed by a horizontal flow wrapping process, although any suitable process may be used. In the flow wrapping process a web of the multi-ply material is folded, with the (usually longitudinal) edges being brought together around the product and sealed together, to form a fin seal 20 extending in the machine direction which defines one edge wall 15. The material is cut transversely to form an appropriate length of package 10 for the product and end seals 19are formed to seal the cut edges, and thus forming the ends 17,18. The fin seal 20 and end seals 19 are preferably hermetic seals so to maintain the freshness of the product prior to the initial opening. The seals may be heat seals, cold seals, pressure sensitive adhesive seals or seals formed by ultrasonic induction. However any other suitable seals may be used depending on the contents of the package 10. Where the package is used for a meltable product, such as chocolate, a cold seal is preferable so as not to damage the product.

Prior to formation of the package 10, the multi-ply material is provided with a plurality of corresponding pairs of lines of weakness 25, 26, such as perforations or score lines, which may be die-cut or laser formed. In order to form the perforations or score lines using a laser, a single laser may be used to source a laser beam to cause an ablation effect that evaporates and melts the material. To achieve this the laser wave length laser power and duration of exposure, amongst other things. The use of a laser in such an application in order to completely cut through flexible wrapping materials is well known in the art. However, in order to form score lines, the power and duration and/or of the laser beam application must be modified to avoid completely cutting through the material.

The pairs of lines of weakness 25,26 are located such that, when the package 10 is formed, they repeat along the package 10 in a first direction. This may be along the length of the package 10 or, in some cases, across the width. The lines of weakness 25, 26 extend around the circumference of the package 10 in a second direction which is generally transverse to the first direction. In each corresponding pair, one line of weakness 25 is formed in the outer layer 12 (shown as solid lines in Figures 1 and 2) and the other line of weakness 26 is formed in the inner layer 11 (shown as dotted lines in Figures 1 and 2). In the embodiment illustrated the line of weakness 25 extends from a notch 30, or other tear initiation point, formed in the fin seal 20, across the fin seal 20, across the front wall 13, around the edge 16, back across the back wall 14 and across the back side of the fin seal 20 to terminate at the notch 30. The location of the line of weakness 25 across the front wall 13 is offset longitudinally relative to the location of the line of weakness 25 across the back wall 14. The second line of weakness 26 of each pair is formed in the inner layer 11 and also extends from the notch 30 across the fin seal 20, across the front wall 13, around the edge 16, back across the back wall, across the back side of the fin seal 20 and terminating in the notch. However, the paths of the lines 25,26 are different and are longitudinally offset relative to each other. The size of the offset depends on the thickness of the product which goes in the package 10 for the reasons described below.

Thus when a tear is initiated at the notch 30, the outer layer 12 tears along the line of weakness 25 and the inner layer 11 simultaneously tears along the line of weakness 26. As the tear progresses along the diverging lines of weakness 25, 26 the layers 11,12 are forced to separate or peel apart from each other with the package 10 dividing into two sections A and B (see Figures 4a,4b and 6). Where the sections A, B have separated, flaps 35, 36, 37, 38 are formed from sections of the separated inner and outer layers 11,12, which can be used to reclose the exposed ends of the package 10. In the illustrated example, the front wall 13 of section A has a flap 35 formed from the outer layer 12(referenced as 12/13 on Figure 5); the back wall 14 of section A has a flap 36 formed from the exposed inner layer 11 (referenced as 11/14 on Figure 5); the front wall 13 of section B has a flap 37 formed from the exposed inner layer 11 (referenced as 11/13 on Figures 4a and 4b); and the back wall 14 of section B has a flap 38 formed from the outer layer 12 (referenced as 12/14 on Figures 4a and 4b). Where the layers 11,12 have separated from each other, the flaps 36,37 formed from the exposed inner layer 11 and the flaps 35,38 formed from the exposed outer layer and have a layer of adhesive which enables them to be re-adhered together in a different configuration as described below.

The length of the flaps 35,36,37,38 Is determined by the offset of the lines of weakness 25,26 between the front or 13 and backwall 14 as described previously. Where the packaged product is relatively thick, the flaps 35,36,37,38 will need to be longer than for a thinner product. This is important to ensure that the flaps 35,36,37,38 do not stick to the packaged product.

Whilst the adhesive provides the means for reclosing the package sections A, B, it preferably also provides a seal.

The packaged product is preferably segmented by a plurality of segment lines (extending in approximately the same direction as the second direction of the package 10) so that individual pieces can be broken off along the segment lines. Thus, a consumer wishing to consume a portion of the product may break the product 19, whilst still enclosed in the package 10, along a chosen segment line to provide a portion of the desired size. He may then initiate a tear at a notch 30 which is adjacent the break. The product portion can then be separated from the remaining product bar still enclosed in the separated package section A ready for consumption. The remaining section B of the package 10 may then be reclosed around the remaining product by folding flap 38 (which is formed from the outer layer 12) over the exposed end of the product, and adhering it to flap 37 (which is formed from the inner layer 11). Once the separated product section has been consumed the now obsolete separated package section A can be disposed of.

If the separated product portion is not to be consumed immediately, the separated package section A can be reclosed around it in a similar manner, with flap 35 (which is formed from the outer layer 12) being folded over the exposed end of the product, and adhered to flap 36 (which is formed from the inner layer 11). This process can be repeated to provide more than are separated sections of the product and the package .

Optionally the package 10 may be provided with means for permitting the opening of the entire package 10 at once. This may be in the form of lines of weakness, such as scoring, along an entire edge.

The package 10 illustrated and described above has front and back walls 13, 14, edge walls 15, 16 and end walls 17,18 suggesting a rectangular flat package, which is the most common shape used for chocolate bars. However, the package 10 of the present invention may be of any suitable shape which permits its separation into sections and enables it to be reclosed by folding over the remaining flaps where the inner and outer layers 11, 12 have separated. Thus the package 10 could have any initial cross sectional shape, for example with a continuous single side wall, such as a cylinder, or it may be triangular and have three side walls etc. The flexible nature of the material enables the package 10 to be flattened regardless of its initial cross section shape to make it easy to stick the remaining flaps down.

Claims

CLAIMS : -

1. A package having at least one side wall defining an interior of the package for receiving a product, said package being formed from a multi-ply material comprising at least an inner layer peelably adhered to an outer layer wherein a plurality of lines of weakness are provided in the outer layer spaced apart along a first direction of the package and a corresponding plurality of longitudinally spaced apart lines of weakness are provided in the inner layer, each line of weakness extending in a second direction which is generally transverse to the first direction, the lines of weakness in the inner layer being offset in the first direction to the corresponding lines of weakness in the outer layer, such that the side wall is separable along a corresponding pair of lines of weakness in the inner and outer layer to form two package sections, each package section having an inner layer flap and an outer layer flap formed by the separation of the inner and outer layers providing means for reclosing the package sections.

2. A package as claimed in claim 1 in which the layers are formed from the same material.

3. A package as claimed in claim 1 in which the layers are formed from different materials.

4. A package as claimed in claim 2 or claim 3 in which the material(s) is (are) flexible material(s).

5. A package as claimed in any one of the preceding claims in which the lines of weakness extend from and terminate at a single tear initiation point.

6. A package as claimed in any one of the preceding claims further comprising means for opening the entire package in a single action.

7. A package as claimed in any one of the preceding claims in which the lines of weakness are formed by cutting, scoring or perforating the layers.

8. A package as claimed in any one of the preceding claims containing a product.

9. A method of packaging a material in a multi-ply material comprising at least an inner layer peelably adhered to an outer layer by means of a resealable pressure sensitive adhesive, said method comprising the steps of forming lines of weakness in the outer layer spaced apart along a first direction; forming a corresponding plurality of spaced apart lines of weakness in the inner layer, each line of weakness extending in a second direction which is substantially transverse to the first direction, the lines of weakness in the inner layer being offset in the first direction to the corresponding lines of weakness in the outer layer; providing a product to be packaged and enclosing the product in the packaging material.