US20130295242A1

US20130295242A1 - Packaging with monoaxially oriented film

Info

Publication number: US20130295242A1
Application number: US13/861,499
Authority: US
Inventors: Parbinder Cheema
Original assignee: Cadbury UK Ltd
Current assignee: Cadbury UK Ltd
Priority date: 2010-09-10
Filing date: 2013-04-12
Publication date: 2013-11-07

Abstract

A flexible package (14) comprises one or more lengths of flexible material (16) arranged to define an internal cavity closed by means of seals (18, 22, 24) in which opposed regions of the material are bonded together. At least one seal (22) has a tab portions (30) in which the material is not bonded to an opposing region of material. The material (16) has directional tear characteristics and is oriented so as to tear preferentially in a direction orthogonal to the direction of said seal. The package is opened by pulling the tab portions (30) so that the material tears along either side of the tab portions in the manner of a tear strip. The material (16) may consist exclusively of a single layer of monoaxially oriented polypropylene film. The tab portions (30) may be formed in an end seal (22) so that material tears in a longitudinal direction of the package. The package may be a flow wrapped package.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. patent application Ser. No. 13/812,989, filed Jan. 29, 2013; which is the National Stage of International Application No. PCT/GB2011/051594, which designates the U.S., filed Aug. 24, 2011, which claims the benefit of Great Britain Application No. GB 1015055.5 filed Sep. 10, 2010, the contents of which are incorporated by reference herein.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to packaging, and in particular, but not exclusively, to packaging for food and more specifically confectionery products.

BACKGROUND TO THE INVENTION

It is known to package food products such as chocolate bars and other snack type confectionery products in a package which is formed from a length of flexible material. The material has an inner surface directed to the food product and an outer surface. The outer surface may be printed on or otherwise be provided with information for the consumer. In some processes, the material is supplied as part of a continuous roll or film.
One known packaging arrangement is commonly referred to as a flow-wrap package. This type of package is produced using a flow-wrap method in which a film of material is supplied in a roll to package a number of products in a substantially continuous process. The method is suitable for wrapping generally rigid products including generally blocked shaped products such as chocolate or other confectionery bars and the like. However, the method can be modified to package products of different shapes or to package a stack or array of smaller products positioned side-by-side.
In the flow-wrap method, the material is fed through a machine which folds it about each product or each stack of products in turn so that opposing longitudinal side edges are brought into face to face contact and bonded together to form a longitudinal fin seal. The material is crimped at either end of the product or stack to form transverse end seals and the material is cut to separate each package from the remainder of the film. The seals may be formed using an adhesive to bond the opposing surfaces of the material or by fusing the material together to form a welded seal. There are a number of known techniques for producing welded seals including heat sealing and ultra sonic sealing. When used to package a product using this method, the material is often referred to as a wrapper as it is wrapped around the product.
Flexible packaging can also be formed from a length of flexible material using a form, fill and seal (“FFS”) operation to produce a bag or pouch type arrangement. This type of packaging is often used to package flowable products such as liquids and powders or for containing a number of smaller product items such as: savoury snacks, nuts, dried fruit, small cookies, crackers, gum pellets, mints, gums, hard boiled sweets, candies, chocolates, toffees and the like. In an FFS operation, an end of a continuous film of material is folded and sealed to define a cavity which is open at one end. The partially formed bag is separated from the remainder of the material and filled with product though its open end. The open end is then sealed to form the completed package. The operation may be a vertical or horizontal fill as is known in the art. The pouch cavity may be gas flushed (e.g. N₂or CO₂) before the bag is closed. Bag or pouch type packages can also be formed using two or more lengths of material which are overlaid and sealed together to define an inner cavity for containing a product. For example a bag or pouch type package can be formed by positioning a first length of material over a second and bonding the two lengths together along three edges to form a partially constructed package. Product is then intruded though the open end which is subsequently sealed.
It is known to produce flexible packages of the types referred to above from a variety of materials including polymeric materials, metallic foil, and paper. Often the material will be a laminate having two or more layers of different materials. For packaging confectionery products, a commonly used laminate comprises an inner layer of paper and an outer layer of a metallic, often aluminium, foil. However, other materials have been used, including polymeric materials which may include thermoplastic materials such as polyethylene terephthalate (PET), for example. Depending on the types of materials used, the known packages may be substantially gas and moisture impervious. However, for some food and confectionery applications, a hermitically sealed package is not desirable.
A problem with the known flexible packages is that the material used is typically quite tough. This makes opening the package difficult as the material does not easily tear in a controlled fashion. To assist a consumer in gaining access to the packaged products, it is common practice to provide a tear guide in or on the material which assists a consumer in tearing the package along a predetermined line.
One known form of tear guide comprises a separate strip of material which is attached to an inner surface of the packaging material. The strip is made of a material which is stronger than the packaging material and an end of the strip is exposed in the finished package so that it can be grasped by a user and pulled to tear the packaging material along the line of the strip. Use of a separate tear strip is disadvantageous as it requires the manufacture and storage of an additional component, i.e. the strip, as well as an additional process step of applying the strip to the packaging material. Where packages are formed from a roll of material in a continuous process, such as with flow-wrapped packages, the strip of material is often applied to the material as part of the packaging process. However, in order to apply the strip the machinery must be run at speeds which are significantly lower than the maximum speed that could otherwise be achieved. This is especially so where the strip is applied in a transverse direction of the material. This reduces the efficiency of the packaging process and so leads to an increase in costs.
To overcome these drawbacks, it is known to form one or more lines of weakness in the packaging material to act as a tear guide. Lines of weakness can be formed by means of perforations which extend through the packaging material but this is not suitable where the product is perishable as the integrity of the sealed package is lost. Alternatively, score lines can be formed which extend only partway through the thickness of the material. Where the packaging material is a laminate, it is known to provide a line of weakness which extends through only one or some of the layers so that at least one layer is left intact to maintain the integrity of the package prior to opening. This arrangement though is not always satisfactory as the layer(s) which is/are left intact may still be difficult to tear in a controlled manner.
It is an object of the invention to provide an improved packaging which overcomes or at least mitigates the above problems.

SUMMARY OF THE INVENTION

In accordance with a first embodiment of the invention, there is provided a flexible package comprising one or more lengths of flexible material arranged to define an internal cavity closed by means of one or more seals in which opposed regions of the material are bonded together, the package having one or more tab portions in which the material is not bonded to an opposing region of material associated with one seal, the material having directional tear characteristics and being orientated so as to tear preferentially in a direction substantially orthogonal to the direction of said seal.
The material may comprise a plastics film having directional tear characteristics. The material may a monoaxially orientated polypropylene film. In one embodiment, the material consists exclusively of a single layer of monoaxially orientated polypropylene film. In a further embodiment, the material is a lamination comprising a layer of polyethylene terephthalate (PET), a layer of aluminium foil, and a layer of oriented polypropylene film.
At least the outer end of the, or each, tab portion may project beyond an outer end of the remainder of said seal. The whole of the, or each, tab portion may project beyond the outer end of the remainder of said seal.
In an embodiment a tab region is defined within said seal, the opposed regions of material within the tab region being bonded together only over an inner extent of the seal, the opposed regions of material within the tab region but outside the inner extent are not bonded together to form opposed tab portions.
The one or more tab portions may extend in a direction substantially orthogonal to the direction of said seal.
The seal may be a transverse seal closing one end of the package and the material may be oriented to tear preferentially in a longitudinal direction.
The package may be formed from a single length of flexible material. In which case, opposed side edge regions of the material may be bonded together to form a longitudinal seal and opposed end regions of the material may be bonded together to form transverse seals at either end of the package, and the one or more tab portions may be associated with one of the end seals, the material being orientated to as to tear preferentially in a longitudinal direction of the package. The longitudinal seal may be a fin seal.
In an embodiment, the package is in the form of a bag or pouch closed at an upper end by means of a sealed header, the one or more tab portions being associated with the header.
In accordance with a second embodiment of the invention, there is provided a package assembly comprising a flexible package as claimed in any one of the preceding claims enclosing one or more products.
The one or more products may comprise at least one generally block shaped product. In which case, the at least one generally block shaped product may be frangible and may comprise two or more separable portions divided from one another by elongate regions or grooves of reduced thickness along which the product can be broken, the one or more tab portions being aligned with a region of reduced thickness. The product may be a chocolate bar.
In accordance with a third embodiment of the invention, there is provided a method of manufacturing a flexible package from one or more lengths of flexible material, the method comprising arranging the one or more lengths of material to define an internal cavity and bonding together opposed regions of the material to form one or more seals closing the cavity, the method includes forming one or more tab portions in which the material is not bonded to an opposing region of material associated with one seal, the material having directional tear characteristics and the method comprising orienting the material such that it is orientated so as to tear preferentially in a direction substantially orthogonal to the direction of the said one seal.
The one or more tab portions may be aligned in a direction substantially orthogonal to the direction of the seal.
The method may comprise applying adhesive to a region of the material for producing said one seal when the package is formed, no adhesive being applied in two areas within said region, which areas overlie one another when the material is formed into the package.

DETAILED DESCRIPTION OF THE INVENTION

Several embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

FIG. 1 is a plan view of a first embodiment of a package in accordance with the present invention showing the package in a closed condition;

FIG. 2 is a view of the package of FIG. 1 taken from one side;

FIGS. 3 and 4 are views similar to FIGS. 1 and 2 but showing the package in a partially opened condition;

FIG. 5 is a plan view of a section of material for use in forming the package of FIGS. 1 to 4;

FIG. 6 shows a first embodiment of a rotary knife for use in forming the package of FIGS. 1 to 4;

FIG. 7 shows a second embodiment of a rotary knife for use in forming the package of FIGS. 1 to 4;

FIG. 8 is a plan view of the end of a package similar to that shown in FIG. 1 but illustrating an alternative opening tab arrangement;

FIG. 9 is a perspective view of a second embodiment of a flexible package in accordance with the invention; and

FIG. 10 is view similar to that of FIG. 9 but shown the package after removal of an outer header region.

The same reference numbers but increased by 100 in each case will be used to identify the same or similar features in each of the embodiments to be described.
FIGS. 1 to 4 illustrate a first embodiment of a packaging assembly 10 in accordance with the invention. The package assembly 10 comprises one or more products, in this case a chocolate bar 12, which is encased in a generally tubular package 14 formed from a length of flexible material 16 in the form of a wrapper.
The material 16 is folded around the product and sealed to define a cavity fully enclosing the product. Opposing side edge regions of the material 16 are bonded together, inner face to inner face, to form a longitudinal fin seal 18 which extends along a rear face 20 of the package. Opposing end edge regions of the material 16 that extend beyond the ends of the chocolate bar are bonded together in face to face relation to form transverse end seals 22, 24 at either end of the product in a known manner.
In the present embodiment, the seals are formed by bonding the opposed edge regions of the material together using a cold seal adhesive 26 to produce seals that can be peeled apart. However, the seals can be produced using other types of adhesive or by fusing the material together to form a welded seal using any known methods such as heat welding or ultra-sonic welding.
The package 14 is a flow-wrap package and will typically be produced using a flow wrap packaging machine (not shown) in a known manner. In this type of operation, the material 16 is provided as part of a continuous roll that is fed into the machine and folded about each product in turn. The inner surfaces of opposing side edge regions of the material are brought into contact and bonded together to form the longitudinal fin seal 18. Opposing edge regions of the material at either end of the product are also brought into contact and bonded to form the transverse end seals 22, 24 and the material is cut to separate each package 14 from the remainder of the film. Once formed in to a package, the material 16 defines an internal cavity in which the product is received and which is enclosed by the seals 18, 22, 24.
The material 16 is a flexible material having directional tearing characteristics. That is to say the material tends to tear preferentially in one direction so that once a tear is initiated in the preferred direction, the tear will tend to propagate in a substantially straight line in the preferred direction. In one non-limiting example, the material consists exclusively of a single layer of monoaxially orientated polypropylene (OPP) film. Monaxially orientated polypropylene films have a reduced tear strength in the direction of orientation and so will tend to tear preferentially in that direction once tearing has been initiated. In a further non-limiting example, the material 16 is a lamination comprising an outer layer of polyethylene terephthalate (PET), an inner layer of an orientated plastics film (such as Terolen®), with a layer of aluminium foil between the outer and inner layers. Other suitable materials can be used provided the material selected has directional tear characteristics. The material 16 may be printed on in the usual manner and may be subject to surface treatments, provided that it retains its directional tear characteristics.
When forming the package, the material 16 is orientated so that it will tear preferentially in a longitudinal direction of the completed package 14, that is to say in a direction substantially orthogonal to the direction of the transverse end seals 22, 24. This is typically the direction in which the film is fed from the roll into the machine and is often referred to in the art as the machine direction and is indicated in FIG. 5 by arrow A.
A tab region 30 is formed in one of the transverse end seals 22. The tab region 30 is a portion of the end seal 22 in which opposed regions of the material 16 are bonded together to form a seal only over an inner extent 34 of the seal. This can be seen best in FIG. 3 in which the shaded region 34 indicates the extent of cold seal used to form the seal in the tab region. The remainder of the opposed regions of material within the tab region 30 but outside of the inner sealed extent are not bonded and form separable tab portions 32 which can be pulled apart by a user to initiate tearing of the material. In the remainder of the end seal 22, the opposed regions of material are bonded together over substantially the whole of their longitudinal extents in the usual manner.
To open the package 14, a consumer grips the separable tab portions 32 and pulls them apart. This initiates tearing of the material at either side of the tab region. Due to the directional tear characteristic of the material, the tears propagate along the length of the package in generally straight lines as indicated by the dashed lines 40 in FIG. 1. The result is the formation of a longitudinal tear strip 42 as shown in FIGS. 3 and 4, the tear strip being substantially the same width as the tab region. The consumer may tear only one face of the package as shown or may pull both the separable tab portions 32 away from the main body of the package so as to tear both faces of the package simultaneously.
Whilst the whole end seal 22 is formed using a peelable cold seal adhesive, the greater depth of the seal outside the tab region 30 makes it harder for the opposed regions of material to be pulled apart than is the case within the tab region. By suitable design, it can be arranged that when the tab portions 32 are pulled apart, the seal within the tab portion 30 will tend to peel apart and the material tear in preference to the whole seal being pulled apart.
The outer ends 36 of the separable tab portions 32 protrude beyond the outermost end 38 of the remainder of the end seal 22. This assists the user in identifying and grasping the tab portions 32. Notches (not shown) may also be formed in the end seal either side of the protruding parts of the tab portions to help initiate tearing.
As is common practice, the chocolate bar 12 is divided into a number of discrete separable segments 12 a arranged in rows and columns by means of elongate regions of reduced thickness or grooves 12 b. As illustrated in FIG. 3, the tab region 30 can be aligned with one of the elongate regions of reduced thickness. This enables the user to break off all or part of a column or length of segments by grasping the remaining package either side of the tear strip without touching the bar.
FIG. 5 illustrates a length of film 16 used to form the package 14. The film comprises a number of packaging lengths or wrappers 42, these are shown divided by a chain dashed lines 44 which indicate where the film is cut to separate each package in turn from the remainder of the film. A cold seal adhesive 26 is applied in a frame-shaped pattern to an inner face of each packaging length to form the longitudinal 18 and transverse end seals 22, 24. Each frame-shaped sealing pattern includes two side portions 46, 48 which form the longitudinal seal and two end portions 50, 52 which form the transverse end seals 22, 24 when the material is folded about the product. Inside the frame-shaped sealing pattern is a region 54 of the wrapper on which no cold seal adhesive is applied and which encases the product or products in the completed package 14.
To form the tab region 30, no cold seal adhesive is applied in two rectangular shape areas 56, 57 in one of the end portions 50 which forms the transverse end seal 22. When the material 16 is folded about the chocolate bar 12, the areas 56, 57 oppose one another so that material in these regions is not bonded together and forms the separable tab portions 32 when the end seal 22 is produced. In the present embodiment in which the outer ends of the tab portions 32 project beyond the outer end of the remainder of the seal 22, the areas 56, 57 extend above the general position of the line 44 along which the film is cut to separate one packaging length from the remainder of the film. When each wrapper section is separated from the remaining film, the film is cut along the line 44 over the majority of its width but the cut runs around the upper half (as shown) of the rectangular areas 56, 57 to produce the protruding parts of the tab portions 32. The areas 56, 57 are positioned towards the outer edge of the seal 22 to leave a continuous inner extent of cold seal extending across the material so the package is fully sealed prior to opening.
FIG. 6 illustrates a rotary knife 60 which can be used to separate a package from the remaining film as part of the packaging process. The knife 60 has a blade 62 which is predominantly straight apart from two rectangular sections 64 shaped to cut around the upper half of the areas 56, 57 in which no cold seal is applied to the film form the protruding parts of the tab portions 32. The knife 60 as shown in FIG. 6 will produce a straight edge to the end seals 22, 24. However, the blade can be shaped to produce different edge profiles. For example, FIG. 7 illustrates an alternative embodiment of the rotary knife 60 in which the blade 66 is shaped to produce an undulating edge to the end seals. It will be appreciated that the protruding tab portions need not be rectangular but could be formed in a variety of different shapes, such as a heart shape.
FIG. 8 illustrates an alternative tab arrangement in which the separable tab portions 32 do not protrude beyond the outer edge of the remainder of the seal 22. Rather, in this embodiment notches 68 are formed in the outer edge of seal 22 on either side of the tab region 30. The notches 68 extend inwardly substantially as far as the inner sealed extent of the tab region 30. The outer portions of the opposed regions of material 16 between the notches which are not bonded are separable and form the tab portions 32.
Packaging arrangements in accordance with the invention are easy to open as well as being simple and cost effective to manufacture. There is no requirement to use a tear strip on the inner surface of the material or to form lines of weakness in the material to provide a tear guide as in some prior art arrangements. Whilst lines of weakness are not essential, score lines can be provided on the inner surface of the material to help further define the tear lines if desired.
The invention is not limited to application with the type of flow wrap packaging disclosed in the above described embodiment but can be applied to any suitable package formed from a flexible material having directional tear characteristics by orienting the material so as to tear preferentially in a direction orthogonal to a seal in which a tab region for initiating tearing is formed. Not all the seals used to form the package need be peelable, though it is essential that the seal in the tab region at least is peelable.
FIGS. 9 and 10 illustrate a second embodiment of the invention in which the package 114 is in the form of so called Quad type bag or pouch. The package is formed from a length of flexible material 116 in a conventional manner and is closed at the top by means of a header 170 in which opposing surfaces of the material 116 are bonded together to form a transverse seal. The header includes an inner header region 172 and an outer header region 174. The inner and outer header regions are separated by a line of weakness 176 which extends across the header so that the outer header region 174 can be removed by tearing along the line of weakness.
Within the majority of the inner header region 172, opposing surfaces of the material 116 are bonded together in a peelable manner using a cold seal adhesive 126 (as indicated by the cross shading), although other peelable seal arrangements can be used such as a peelable weld. The seal in the outer header region 174 may be also be a peelable seal or it may be a permanent seal. Thus, in the outer header region 174 the opposing surfaces of the material could be bonded using a permanent, i.e. non-peelable, adhesive or by welding. An aperture 178 is provided in the outer header region by means of which the package can be suspended from a hook for display purposes.
The line of weakness 176 is formed by means of a line of perforations and extends straight across the package except for one area where it projects outwardly (upwardly as shown) to define a tab region 130 which extends beyond the outer edge of the remainder of the inner header region 172. No cold seal 126 is applied to the material within the tab region 130 so that the opposing surfaces of the material are not bonded together when the header 170 is formed. In this embodiment, the tab region 30 is semi-circular in shape but it can be any suitable shape. In the embodiment as shown, only the opposed regions of material in the tab region 130 that are located above the general position of the line of weakness 176 are not bonded together. However, the un-bonded area in which no cold seal 126 is present could be extended inwardly by a limited amount. This would result in an arrangement similar to that in the previous embodiment in which the opposed regions of material within the tab region are only sealed over a smaller inner extent than in the remainder of the inner header region 172. This may help in making it easier to separate the tab portions 132 to initiate tearing. As with the previous embodiment, small cuts or notches may be provided either side of the tab portion 132 to help in initiating tearing.
To open the package, the user first removes the outer header region 174 by tearing along the line of weakness 176. With the outer header removed as shown in FIG. 10, the package remains sealed by virtue of the inner header region 172. The opposed regions of material within the tab region 130 which are not bonded together project from the outer edge of the inner header seal 172 and form separable tab portions 132 which can be grasped by a user and pulled apart to initiate tearing of the material in a longitudinal direction on either side of the tap portions 132. The material 116 is orientated so that it tears preferentially in the longitudinal direction of the package, that is from top to bottom as shown, so that once tearing has been initiated and the tears will tend to propagate in substantially straight lines in the longitudinal direction as indicated by the dashed lines 140 in FIG. 10.
In an alternative embodiment, the package 114 could be manufactured without a removable outer header region 174 so that the package would resemble the package 114 as shown in FIG. 10 when manufactured. Bags and pouches of a similar nature can also be formed in accordance with the invention from one or more lengths of flexible material joined together by means of seals to define a cavity. In this case, at least one of the lengths of material should have directional tear characteristics and be orientated so as to tear preferentially in a desired direction when a tab portion 132 associated with one of the seals is pulled.
The terms “longitudinal” and transverse” are used herein to define relative directions of the package or parts thereof in which the “transverse” direction is substantially orthogonal to the “longitudinal” direction. Depending on the design of any particular package, its “longitudinal” dimension many be longer or shorter than its “transverse” dimension.
The foregoing embodiments are not intended to limit the scope of protection afforded by the claims, but rather to describe examples as to how the invention may be put into practice. For example, whilst the embodiments described above are adapted for packaging confectionery products, the packaging arrangements described herein can be adapted for packaging other food and indeed non-food products.

Claims

1. A flexible package comprising one or more lengths of flexible material arranged to define an internal cavity closed by means of one or more seals in which opposed regions of the material are bonded together, the package having one or more tab portions in which the material is not bonded to an opposing region of material associated with one seal, the material having directional tear characteristics and being orientated so as to tear preferentially in a direction substantially orthogonal to the direction of said seal.

2. A flexible package as claimed in claim 1, in which the material comprises a plastics film having directional tear characteristics.

3. A flexible package as claimed in claim 2, in which the material comprises a monoaxially orientated polypropylene film.

4. A flexible package as claimed in claim 1, in which the material consists exclusively of a single layer of monoaxially orientated polypropylene film.

5. A flexible package as claimed in claim 1, in which the material is a lamination comprising a layer of polyethylene terephthalate (PET), a layer of aluminium foil, and a layer of oriented polypropylene film.

6. A flexible package as claimed in claim 1, in which, at least the outer end of the, or each, tab portion projects beyond an outer end of the remainder of said seal.

7. A flexible package as claimed in claim 6, in which the whole of the, or each, tab portion projects beyond the outer end of the remainder of said seal.

8. A flexible package as claimed in claim 1, in which a tab region is defined within said seal, the opposed regions of material within the tab region being bonded together only over an inner extent of the seal, the opposed regions of material within the tab region but outside the inner extent are not bonded together to form opposed tab portions.

9. A flexible package as claimed in claim 1, in which the one or more tab portions extend in a direction substantially orthogonal to the direction of said seal.

10. A flexible package as claimed in claim 1, in which the seal is a transverse seal closing one end of the package and the material is oriented to tear preferentially in a longitudinal direction.

11. A flexible package as claimed in claim 1, in which the package is formed from a single length of flexible material.

12. A flexible package as claimed in claim 11, in which opposed side edge regions of the material are bonded together to form a longitudinal seal and opposed end regions of the material are bonded together to form transverse seals at either end of the package, the one or more tab portions being associated with one of the end seals and the material being orientated to as to tear preferentially in a longitudinal direction of the package.

13. A flexible package as claimed in claim 12, in which the longitudinal seal is a fin seal.

14. A flexible package as claimed in claim 1, in which the package is in the form of a bag or pouch closed at an upper end by means of a sealed header, the one or more tab portions being associated with the header.

15. (canceled)

16. A package assembly comprising a flexible package as claimed in claim 1 enclosing one or more products.

17. A package assembly as claimed in claim 16, in which the one or more products comprises at least one generally block shaped product.

18. A package assembly as claimed in claim 17. in which the at least one generally block shaped product is frangible and comprises two or more separable portions divided from one another by regions of reduced thickness along which the product can be broken, the one or more tab portions being aligned with a region of reduced thickness.

19. A package assembly as claimed in claim 16, in which the product is a chocolate bar.

20. (canceled)

21. A method of manufacturing a flexible package from one or more lengths of flexible material, the method comprising arranging the one or more lengths of material to define an internal cavity and bonding together opposed regions of the material to form one or more seals closing the cavity, the method includes forming one or more tab portions in which the material is not bonded to an opposing region of material associated with one seal, the material having directional tear characteristics and the method comprising orienting the material such that it is orientated so as to tear preferentially in a direction substantially orthogonal to the direction of the said one seal.

22. A method as claimed in claim 21, in which the one or more tab portions are aligned in a direction substantially orthogonal to the direction of the seal.

23. A method as claimed in claim 21, in which the method comprises applying adhesive to a region of the material for producing said one seal when the package is formed, no adhesive being applied in two areas within said region, which areas overlie one another when the material is formed into the package.

24. (canceled)