GB2547890A

GB2547890A - Package

Info

Publication number: GB2547890A
Application number: GB1603070.2A
Authority: GB
Inventors: Shaw Mark; Hill Mark
Original assignee: Parkside Flexibles Europe Ltd
Current assignee: Parkside Flexibles Europe Ltd
Priority date: 2016-02-23
Filing date: 2016-02-23
Publication date: 2017-09-06
Also published as: GB201603070D0

Abstract

An ovenable package 1 comprises an enclosure formed of an ovenable laminate film. The ovenable laminate film comprises at least a first layer 38 and a second layer 31 inside the first layer 38. An openable portion 15 of the enclosure is openable to define an access aperture to an interior of the enclosure. The openable portion 15 is defined by a first cut line 11 formed in the first layer 38 but not in the second layer 31. A second cut line 12 is formed in the second layer 31 but not in the first layer 38. The second cut line 12 is offset from the first cut line 11 by a peripheral region 13 of the second layer 31. There is a non-permanent adhesive 39 between at least the peripheral portion 13 of the second layer 31 and the first layer 38. The package is openable by separating the first layer 38 of the openable portion 15 from the second layer 31 of the openable portion in the peripheral region 13.

Description

PACKAGE

Background

Some food products are packaged ready for heating in an oven. One type of ovenable package is a sealed bag or pouch. These packages provide a sealed environment for the food product during the shelf life of the product, and the food product remains within the package during heating in a conventional oven or microwave oven.

In some types of ovenable package, some preparation of the package is required prior to heating. For example, a user may be required to puncture the bag or to tear a corner of the package. This preparation allows the package to vent during heating. During heating, gas (e.g. steam) can safely escape from the package. This prevents the package from bursting during heating.

One disadvantage of some ovenable packages is that there is a scalding risk when a user attempts to open the package to serve the heated food. Packages may carry a warning which advises a user to allow a period after heating has completed before opening the package so as to allow steam to vent from the package or for the temperature within the package to reduce to a safer level.

There is a requirement for alternative packaging.

Summary

This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

An aspect of the disclosure provides an ovenable package comprising: an enclosure formed of an ovenable laminate film, the ovenable laminate film comprising at least: a first layer; and a second layer inside the first layer; an openable portion of the enclosure which is openable to define an access aperture to an interior of the enclosure, the openable portion defined by: a first cut line formed in the first layer but not in the second layer; a second cut line formed in the second layer but not in the first layer, the second cut line defining the access aperture, wherein the second cut line is offset from the first cut line by a peripheral region of the second layer; a non-permanent adhesive between at least the peripheral portion of the second layer and the first layer; wherein the package is openable by separating the first layer of the openable portion from the second layer of the openable portion in the peripheral region.

The non-permanent adhesive may be a re-adherable adhesive. The openable portion can be reclosed to put the package into a veritable state, wherein the ventable state permits venting of gas from an interior of the enclosure between the first layer and the peripheral region of the second layer.

The openable portion may have a first region which is intended to be grasped by a user, wherein a width of the peripheral region varies around a perimeter of the openable portion, and wherein the width of the peripheral region is greatest proximate the first region.

The width of the peripheral region proximate the first region may be at least three times, optionally at least four times, greater than the width of the peripheral region at other points around the perimeter of the openable portion. A maximum width of the peripheral region proximate the first region may be at least 3cm, optionally at least 4cm, optionally at least 5cm.

The openable portion may have a first region which is intended to be grasped by a user, wherein the non-permanent adhesive is a re-adherable adhesive and wherein an adhesive bond strength of the re-adherable adhesive in the peripheral region varies around a perimeter of the openable portion. The adhesive bond strength in the peripheral region at a point around the perimeter of the openable portion, spaced from the first region, may be less than the adhesive bond strength in the peripheral region proximate the first region.

The openable portion may have a first region which is intended to be grasped by a user, wherein a width of the openable portion varies along a length of the openable portion, and wherein the width of the openable portion has a minimum value at the first region. A width of the openable portion may decrease along a length of the openable portion, the width of the openable portion having a minimum value at the first region.

The openable portion may have a substantially triangular shape.

The ovenable package may have a set of corners, wherein the first cut line extends between a first corner and a second corner of the package.

The package may be rectangular and wherein the first corner and the second corner are opposing ends of one side of the rectangular package. The term “rectangular” includes a square package. A width of the peripheral region may vary around a perimeter of the openable portion, and wherein the width of the peripheral region is least proximate the first corner and the second corner.

The non-permanent adhesive may be a re-adherable adhesive and wherein the re-adherable adhesive is more strongly attached to the first layer than the second layer such that the re-adherable adhesive is carried by the first layer when the first layer is separated from the second layer.

The openable portion may be a flap, the first cut line and the second cut line each defining an open path with a respective first end point and a respective second end point.

The first cut line and the second cut line may each form a closed path.

Only a non-permanent adhesive may be provided between the first layer and the second layer. A bond strength of the non-permanent adhesive may be lower on the peripheral portion of the second layer compared to elsewhere on the second layer.

The non-permanent adhesive may only be provided between the peripheral portion of the first layer and the second layer, and a permanent adhesive is provided elsewhere between the first layer and the second layer.

The laminate film may be printed on an outer face of the first layer.

The laminate film may be printed between the second layer and the first layer.

The ovenable package may be in the form of an ovenable bag, an ovenable pouch, or another type of enclosed package.

Another aspect of the disclosure provides an ovenable laminate film for forming an ovenable package, the ovenable laminate film comprising at least: a first layer; and a second layer inside the first layer; an openable portion which is openable to define an access aperture, the openable portion defined by: a first cut line formed in the first layer but not in the second layer; a second cut line formed in the second layer but not in the first layer, the second cut line defining the access aperture, wherein the second cut line is offset from the first cut line by a peripheral region of the second layer; a non-permanent adhesive between at least the peripheral portion of the second layer and the first layer; wherein the openable portion is openable by separating the first layer of the openable portion from the second layer of the openable portion in the peripheral region.

Another aspect of the disclosure provides a method of manufacturing an ovenable package comprising: providing an ovenable laminate film; forming the ovenable laminate film into a package; sealing the package.

Another aspect of the disclosure provides a method of manufacturing an ovenable laminate film for use in forming an ovenable package comprising: providing an ovenable first layer; and providing an ovenable second layer; laminating the first layer to the second layer to form an ovenable laminate film; forming an openable portion in the laminate film by: forming a first cut line in the first layer but not in the second layer; forming a second cut line in the second layer but not in the first layer, the second cut line defining an access aperture, wherein the second cut line is offset from the first cut line by a peripheral region of the second layer; wherein the laminating uses a non-permanent adhesive between at least the peripheral portion of the second layer and the first layer.

An advantage of at least one example is ease of opening the package.

An advantage of at least one example is a reduced scalding risk to a user.

An advantage of at least one example is that the package is ventable without the need to form vent apertures using a sharp implement.

In this specification, the term “non-permanent adhesive” means an adhesive which allows two surfaces to adhere to one another and which also allows the surfaces to be separated non-destructively from one another.

In this specification, the term “re-adherable adhesive” means an adhesive which allows two surfaces to adhere to one another, allows the two surfaces to be separated non-destructively from one another and subsequently allows the two surfaces to re-adhere to one another. An example of a re-adherable adhesive is a Pressure Sensitive Adhesive (PSA), such as a peelable PSA, where an adhesive bond is achieved by applying pressure to the adhesive.

In this specification, the term “ovenable” means the package is formed of an oven grade material which is capable of withstanding heating in an oven, such as a conventional oven (gas, electric) or microwave oven for a cooking period. Typically the cooking period is less than one hour.

The preferred features may be combined as appropriate, as would be apparent to a skilled person, and may be combined with any of the aspects of the invention.

Brief Description of the Drawings

Embodiments of the invention wiii be described, by way of exampie, with reference to the foiiowing drawings, in which:

Figure 1 shows an ovenabie package in pian view;

Figure 2 shows a cross-section through the package of Figure 1 aiong iine Y-Y’;

Figure 3A shows a cross-section through the package of Figure 1 aiong iine X-X’ with the package in an unopened state;

Figure 3B shows a cross-section through the package of Figure 1 along line X-X’ with the package in an opened state;

Figure 4 shows iayers of the iaminate of the package of Figure 1;

Figures 5A-5D show a sequence of using the package;

Figure 6 shows an exampie of the package with a variable width peripheral region;

Figure 7 shows another exampie of the package with a variable width peripheral region;

Figure 8 shows an exampie of the package with a variable strength adhesive bond in the peripherai region;

Figure 9 shows an exampie of the package in which the openabie portion has a distal end of reduced width;

Figure 10 shows another exampie of the package in which the openabie portion has a distai end of reduced width;

Figure 11 shows another exampie of the package in which the openabie portion has a distai end of reduced width;

Figures 12A-12D show a sequence of using another exampie of the package;

Figure 13 shows an exampie of the package in which the openabie portion is removabie;

Figures 14A-14D show exampies of cut iines;

Figure 15 shows a package with printing;

Figures 16A and 16B show a package in the form of a pouch.

Common reference numerais are used throughout the figures to indicate simiiar features.

Detailed Description

Embodiments of the present invention are described below by way of example only. These examples represent the best ways of putting the invention into practice that are currently known to the Applicant although they are not the only ways in which this could be achieved. The description sets forth the functions of the example and the sequence of steps for constructing and operating the example. However, the same or equivalent functions and sequences may be accomplished by different examples.

Figures 1 to 3 show an example of a package 1 in the form of a bag or pouch. Figure 1 shows the package in plan view, viewed from the front. Figure 2 shows a cross-section through the package taken along the line Y-Y’ of Figure 1. Figure 3 shows a cross-section through only the front face 7 of the package taken along the line X-X’ of Figure 1. The package 1 comprises a flexible sheet material 10 which is folded to form an enclosure having a front face 7 and a back face 8. The package 1 has an interior volume 9 which can hold a product. The product can be any food product which is intended to be stored for a period of time, and then cooked in the package 1. Products include vegetables (e.g. frozen or chilled), rice, pasta, quinoa, protein (e.g. meat, fish, mushrooms). The product may be in solid form or liquid form.

The flexible sheet material 10 is a multi-layer laminate. The laminate is formed of an oven grade material. The oven grade material is able to withstand heating in an oven for a typical cooking period without melting. A package may be: configured for heating in a microwave oven and a conventional oven; configured for heating in a microwave oven only; or configured for heating in a conventional oven only. The main differences between the oven types are: (i) temperature and (ii) heating time. Typically, food is heated in a conventional gas or electric oven at temperatures between 155°C and 220°C for a period of up to one hour. Typically, food is heated in a microwave oven at a lower temperature for a shorter period. A microwave oven primarily cooks by exciting water molecules in the food, which generates more steam and hence a higher pressure within the package compared to conventional cooking.

Examples of suitable oven grade materials for the laminate 10 are polyester based film, such as Polyethylene terephthalate (PET), nylon, polyactic acid (PLA) film, cellulose, or any other suitable oven-grade polymer. For a package which is intended for conventional cookers, the sheet material should not become brittle, melt or release toxins when subjected to temperatures up to 220°C. For a package which is intended for storage in a freezer, the sheet material should also be capable of withstanding low temperatures, such that the material is able to withstand an overall temperature of, for example, -40°C to +220°C. A first seal 23 is formed between the front face 7 and the back face 8 along, or adjacent to, edges 3 of the sheet 10. A second seal 24 is formed between the front face 7 and the back face 8 along, or adjacent to, edges 4 of the sheet 10. A third seal 25 is formed between respective portions of the back face 8 (Figure 2). Seals can be formed by applying heat to the laminate, thereby forming a seal between respective sealant layers of the laminate. Seals 23, 24, 25 are not intended to be opened by a user. In an alternative example, seal 25 can be formed between the front face 7 and the back face 8 along, or adjacent to, one of the edges 5, 6 of the sheet 10.

The package 1 has an openable portion 15. In this example the openable portion 15 is located on the front face 7 of the package. In this example the openable portion is in the form of a flap. When the flap 15 is opened, it provides access to the interior 9 of the package via an access aperture 16 defined by a cut line 12. In the package shown in Figure 1 the flap 15 is hinged about one of the shorter sides of the package, parallel to edge 3.

Figure 3A shows a cross-section through the front face 7 of the package taken along the line X-X’ of Figure 1. In this example the laminate sheet 10 comprises an outer layer 38 and an inner layer 31. The outer layer 38 is bonded to the inner layer 31 by a non-permanent adhesive 39, such as a peelable pressure sensitive adhesive (PSA). In this example, the non-permanent adhesive 39 is a re-adherable adhesive 39 which allows layer 38 to separate from layer 31, and then to re-adhere to layer 31. The non-permanent adhesive 39 can be used between layers 31, 38 locally in a peripheral region of the flap 15, or generally between these layers. Cut lines 11, 12 are formed in the layers 31, 38 of the laminate. Cut lines 11, 12 are formed in different layers of the laminate, and are offset from one another such that a peripheral region 13 of the inner layer 31 is provided where the outer layer 38 can separate from the inner layer 31. In an example where re-adherable adhesive 39 is provided in the peripheral region, layer 38 can subsequently reattach to the peripheral region of the inner layer 31.

The layers 31, 38 can be formed of the same material (e.g. PET or similar) or they can be formed of different materials. An example range of thicknesses for each layer 31, 38 is 12-200pm. For a package which is intended for storage in a freezer, the laminate sheet 10 should also be capable of withstanding low temperatures, such that the material is able to withstand an overall temperature of, for example, -40°C to +220°C.

Figure 4 separately shows the outer layer 38 and the inner layer 31 and the cut lines formed in these layers. The outer layer 38 will form the outside of the package 1 and the inner layer 31 will form the inside of the package 1. A first cut line 11 is formed in the outer layer 38 but not in the inner layer 31. A second cut line 12 is formed in the inner layer 31 but not in the outer layer 38. The cut lines 11, 12 are offset from one another. Cut line 11 in the outer layer 38 defines an outer perimeter of the flap 15. Cut line 12 in the inner layer 31 defines a perimeter of an access aperture 16 (shown exposed in Figures 5A and 5D) in the inner layer 31. Cut line 12 in the inner layer 31 also defines a perimeter of a peripheral region 13 (Figure 1) which extends continuously around three sides of the access aperture.

The cut lines 11,12 define a flap 15 of laminate material which is unitary with the rest of the sheet 10 along one side of the flap. This will be called a hinge region, and is shown by dashed box 17. In use, the flap can hinge about the hinge region 17. Each of the cut lines 11, 12 defines an open path with a respective first end point and a respective second end point. In the peripheral region 13 the outer layer 38 of the flap 15 is separable from the inner layer 31. In a central region of the flap 15 the outer layer 38 will remain adhered to the inner layer 31. The end of the flap 15 furthest from the hinge region 17 will be called the distal end 15A. In use, a user grasps the distal end 15A of the flap 15. The re-adherable adhesive 39 may be patterned to leave a region 14 with less adhesive, or no adhesive at all. This allows the distal end 15A of the flap to serve as a pull tab. The pull tab may therefore be easily lifted up and used to pull open the flap 15. The outer layer 38 separates from the inner layer 31 in region 13. The re-adherable adhesive 39 may remain adhered to the outer layer 38 or to the inner layer 31. Within cut line 12, the outer layer 38 and the inner layer 31 of the laminate will remain bonded to one another and will lift as a unitary element. This creates the access aperture 16.

Figures 5A to 5D show a sequence of drawings of using the package. The front/top of the package is shown in each of these drawings. Prior to Figure 5A the package is in a sealed, unopened, state and the food product within the package is protected from the surrounding environment. The package may be stored in a chilled or frozen environment (e.g. fridge or freezer) before heating. The package may be defrosted before heating, or heated directly from frozen. Alternatively, the package may be stored in an ambient environment before heating. In Figures 5A and 5B the package is prepared for heating. Firstly, the flap 15 of the package is pulled back (Figure 5A). A user may grasp the distal end 15A of the flap and then pull the flap back. This causes the outer layer 38 to separate from the inner layer 31 in peripheral region 13, as far as cut line 12. This separation occurs because the opening force applied by the user is greater than the bond strength of the adhesive 39 between the layers 31, 38. The user may pull the flap fully back to expose most of the peripheral region 13, or may only pull the flap partially back so that only the first part of the peripheral region 13 is exposed.

After pulling back the flap, the user recloses the flap to the state shown in Figure 5B. The user may lightly run their finger along the flap in the region where the outer layer 38 of the flap 15 separated from the peripheral region 13 of the inner layer 31, or may brush their hand across the flap 15 in a sweeping action. This can help to re-attach the outer layer 38 of the flap 15 to the peripheral region 13 of the inner layer 31. The package is now in a ventable state. Due to the initial opening of the flap 15 at Figure 5A, the bond strength of the seal in the part of the peripheral region 13 exposed in Figure 5A is weakened. This reduction in bond strength is desirable, as the lid only needs to re-attach to the first layer to hold the lid in place. The reduced bond strength permits venting.

Subsequent to Figure 5B, the package is heated in an oven. This is shown in Figure 5C. During heating, gas can safely vent from the interior volume of the package. The outer layer 38 can separate from the inner layer 31 in peripheral region 13 to allow gas to vent. The flap continues to cover the access aperture 16. This prevents food escaping from the package, such as hot liquid splashing the interior of the oven.

Optionally, at some point during the heating process, the package may be removed from the oven to stir the contents. The flap 15 can be pulled back, similar to as shown in Figure 5A, and then reclosed as shown in Figure 5B and returned to the oven. An advantage of the package is that the flap can be secured back to the package after opening, thereby preventing splashing.

At the end of the heating process the package is removed from the oven. The flap 15 is fully pulled back. It is also possible to completely remove the flap 15 from the remainder of the package 1 by pulling the flap fully back. The flap separates from the remainder of the package. Figure 5D shows the package after the flap has been removed. This is particularly useful when the contents of the tray require pouring from the package 1. The food contents can be consumed from the package 1 or can be transferred from the package 1 before consumption. Food may be removed or poured from a side edge or corner of the package.

Returning to Figure 1, the peripheral region 13 has a first width 13A at the distal end 15A of the flap 15 where a user will grasp the flap. A large width 13A of the peripheral region at the distal end 15A of the flap can provide an advantage of protecting a user against scalding. Figure 3B shows the same cross-section through the front face 7 of the package as Figure 3A, but with the flap 15 lifted. A user grasps the distal end 15A of the flap as shown by arrows 35. It can be seen how the distal end 15A of the flap is spaced from the path 36 of steam escaping from an interior of the package. This spacing arises from the large offset distance 13A between the cut lines 11, 12. In a non-limiting example this spacing is >3cm, >4cm or >5cm.

It is possible to provide a large offset distance between cut lines 11, 12 around the entire perimeter of the openable portion 15. However, this is undesirable. A large offset distance will reduce the size of the access aperture 16 through which a user removes the food product after heating. Also, a large offset distance could impede the venting of the package. Therefore, in Figure 1 the peripheral region 13 between the cut lines 11, 12 in layers 31, 38 varies in width around the perimeter of the openable portion 15. In the example shown in Figure 1, the peripheral region 13 has a second width 13B along the side edges of the flap 15, where width 13A > width 13B. The reduced width 13B of the peripheral region at the side edges of the flap allows gas (steam) to vent from the package. This reduces the volume of gas within the package at the time that a user opens the package, and therefore also helps to protect a user against scalding.

In the example shown in Figure 3B the non-permanent adhesive 39 is more strongly attached to the outer layer 38 than to the inner layer 31 such that the non-permanent adhesive 39 is carried by the outer layer 38 when the outer layer is separated from the inner layer. In an alternative example, the non-permanent adhesive 39 can remain attached to inner layer 31.

As described above, varying the width of the peripheral region 13 between the layers 31, 38 can allow the package to vent during heating. Examples shown in Figure 1 and Figures 5A-5D provide a reduced width at regions away from where a user grasps the flap 15. Figures 6 to 9 show some other examples of packages where features are provided to vent gas away from where a user grasps the flap 15.

In Figure 6 the peripheral region 13 has a first width 13A at the distal end 15A of the flap 15 where a user will grasp the flap. The peripheral region 13 has a second width 13B along one of the side edges of the flap 15, where width 13A > width 13B. The peripheral region 13 has a third width 13C along the other of the side edges of the flap 15, where width 13A > width 13B > width 13C. Reducing width of the peripheral region 13 can reduce the resistance to venting gas. This increases the likelihood that gas will vent from the reduced width region. This configuration can increase the likelihood of gas venting from the side edge of width 13C.

In Figure 7 the peripheral region 13 has a first width 13A at the distal end 15A of the flap 15 where a user will grasp the flap. The peripheral region 13 has a second width 13B along each of the side edges of the flap 15, where width 13A > width 13B. The peripheral region 13 has a venting feature 40. This is a portion of the peripheral region 13 where the width of the peripheral region is reduced to a width 13D, where width 13B > width 13D. Reducing width of the peripheral region 13 can reduce the resistance to venting gas at this position. The position of the venting feature 40 can be selected so that it is remote from the distal end 15A of the flap which is grasped by a user. In this way, the position of the gas venting is controlled. During heating, gas may be vented from just the venting feature 40, or from a combination of the venting feature 40 and other parts of the peripheral region 13.

In Figure 8 the peripheral region 13 has venting portions 42 with a reduced bond strength of the re-adherable adhesive 39 between the layers 31, 38. In general, there can be one or more venting portions 40 around the peripheral region 13 of the flap 15 where the bond strength is reduced. Reducing bond strength of the re-adherable adhesive between the layers 31, 38 can reduce the resistance to venting gas. This increases the likelihood that gas will vent from these places 42. The position of the venting portion 42, or portions 42, with reduced bond strength can be selected so that they are remote from the distal end 15A of the flap which is grasped by a user. In this way, the position of the gas venting is controlled. During heating, gas may be vented from just the venting portion(s) 42, or from a combination of the venting portion(s) 42 and other parts of the peripheral region 13.

Figure 9 shows another example of a package 1. The peripheral region 13 between the layers 31, 38 varies in width around the perimeter of the openable portion 15. The peripheral region 13 has a maximum width 13A at the distal region 15B of the flap 15 where a user will grasp the flap. This helps to minimise the risk of scalding, as described above. For clarity, the openable portion 15 will be described as having a “length” dimension L which is the longest dimension of the openable portion 15. In this example, the length is directed from the hinged area towards the distal end 15A. The openable portion also has a “width” dimension W which is orthogonal to the length L. Length L and width W are shown in Figure 9. The openable portion 15 comprises a main portion of width W1 and a distal region of width W2, where W1 > W2. The reduced width of the distal region 15B has an advantage of reducing the amount of opening force, as there is a reduced area where the layers 31, 38 are adhered to each other.

Figure 10 shows another example of a package 1. A distal region 15B of the flap 15 has an elongated, “finger”-like, shape. The shape of region 15B helps to provide a clear indication of where a user should grasp the flap 15 for opening. The main region 15C of the flap 15 has a width W1. The distal region 15B of the flap 15 has a maximum width W2, where W2 < W1. The peripheral region 13 between the layers 31, 38 varies in width around the perimeter of the openable portion 15. The peripheral region 13 has a first width 13A at the distal end 15A of the flap 15 where a user will grasp the flap. This helps to minimise the risk of scalding, as described above. The peripheral region 13 has a maximum width 13A only at the tip of the distal region 15B. Away from the tip, the peripheral region 13 has a reduced width 13B, where width 13A > width 13B.

Figure 10 shows length L and width W dimensions for the openable portion 15. A width of the openable portion 15 varies along a length of the openable portion. The width of the openable portion has a minimum value at the distal region 15B, and the distal end 15A. The shape of the distal region 15B of the flap has an advantage of reducing a force required to open the flap, as there is a reduced area where the layers 31, 38 are adhered to each other.

Figure 11 shows another example of a package 1. The flap 15 has a substantially triangular shape when viewed in plan. In this example the cut lines 11, 12 are arcuate, but they could be straight along all or part of their extent. The openable portion 15 has a rounded distal end 15A. The shape of the flap 15 helps to provide a clear indication of where a user should grasp the flap 15 for opening. The peripheral region 13 between the layers 31, 38 varies in width around the perimeter of the openable portion 15. The peripheral region 13 has a first width 13A at the distai end 15A of the flap 15 where a user will grasp the flap. This heips to minimise the risk of scaiding, as described above. The peripheral region 13 has a maximum width 13A oniy at the distai end 15A. Away from the distai end 15A, the peripheral region 13 has a reduced width 13B, where width 13A > width 13B.

Figure 11 shows iength L and width W dimensions for the openabie portion 15. A width of the openabie portion 15 varies aiong a iength of the openabie portion. The width of the openabie portion has a minimum vaiue at the distai end 15A. The shape of the openabie portion 15 has an advantage of reducing a force required to open the flap, as there is a reduced area where the iayers 31,38 are adhered to each other. in the example of Figure 11 the cut line 11 extends to the corners of the package, nearest to edge 3. Cut line 12 also extends near to the corners of the package. The peripheral region 13 between the cut lines 11, 12 has a reduced width 13E proximate the corners. This allows more convenient removal of contents from the package. A user may pour contents from the package with minimal trapping or obstruction. After opening the flap 15, a user may hold the package by one of the corners nearest to edge 4 and pour or tip contents from the package. The user may hold the distal end 15A of the flap, so that they hold the opened package by a corner and by distal end 15A of the flap. Alternatively, the user may fully remove the flap 15 from the package and tip or pour from the package nearest to edge 3.

Figure 11 shows a four-sided package. The principles shown in Figure 11 can be applied to a package with a different number of sides/corners. For example, a package with 3, 5, 6 or more sides.

In any of the examples described above, a non-limiting example range of bond strength for the re-adherable adhesive 39 in the initial unopened state is 100g-400g per 25mm. The bond strength reduces after the package is initially opened. A non-limiting example range of bond strength for the re-adherable adhesive 39 in the veritable state is 50g-100g per 25mm.

The openabie portion 15 can have a shape which matches any printed material (e.g. branding) provided on the package.

The openabie portion 15 can have a shape which matches a product within the package, such as shape of fruit or vegetable within the package.

The openabie portion 15 can extend across a major part of a face of the package. For example, a length of the openabie portion can be >50%, or >60%, or >70%, or >80%, or >90% of the total length of the face of the package. For example, a maximum width of the openabie portion can be >50%, or >60%, or >70%, or >80%, or >90% of the total width of the face of the package. This allows easy access to contents of the package.

In the examples described above the non-permanent adhesive 39 is a re-adherable adhesive. This allows a user to put the package into a ventable state by pulling back, and reattaching, the openable portion 15 before heating. In an alternative example, the nonpermanent adhesive 39 is a peelable adhesive which is not capable of re-adhering. Other features of the package are the same as described above for Figure 1. The package is a bag or pouch formed of laminate with an openable portion 15, such as a flap. The openable portion 15 is formed by offset cut lines 11, 12 in layers of the laminate.

Figures 12A to 12D show a sequence of drawings of using this alternative package. The front/top of the package is shown in each of these drawings. Prior to Figure 12A and 12B the package is in a sealed, unopened, state and the food product within the package is protected from the surrounding environment. Figures 12A and 12B show two alternative ways in which the package can be put into a ventable state. In Figure 12A, the package lacks any feature which allows venting during heating. Therefore, a user punctures the package to form vent apertures 51. A knife, fork or other sharp implement can be used to puncture the flap 15 in a conventional manner. In Figure 12B the package is provided with a venting feature 50 which allows venting during heating. Therefore, a user is not required to puncture the package, although they may still do so. Venting feature 50 can be part of the peripheral region between layers 31, 38 of the laminate which is configured to open when the package is heated to allow venting of gas. For example, the venting feature 50 can be: a region of adhesive having a reduced bond strength; a region of adhesive having a reduced bond strength at cooking temperatures: a valve.

Subsequent to Figure 12A or 12B, the package is heated in an oven. This is shown in Figure 12C. During heating, gas can safely vent from the interior volume of the package. Venting may occur via the apertures 51 or by the venting feature 50.

At the end of the heating process the package is removed from the oven. The flap 15 is pulled back or completely removed from the remainder of the package. Figure 12D shows the package after the flap has been removed. The food contents can be consumed from the package 1 or can be transferred from the package 1 before consumption.

As described above, the peripheral region 13 at the distal end 15A of the flap 15, where a user will grasp the flap, is large enough to minimise scalding. The peripheral region 13 between the cut lines 11, 12 in layers 31, 38 can vary in width around the perimeter of the openable portion 15. The distal end 15A of the flap 15 can have one of the shapes shown in Figures 9 or 10 to reduce the opening force required to peel open the flap 15.

Figure 13 shows an example of a package with an openable portion 15 which is removable. The cut lines 11, 12 each follow a closed path. When the openable portion 15 is first opened, it is pulled back, but not separated from the remainder of the package. When the food is ready for consumption, the openable portion 15 can be fully pulled back and removed from the remainder of the package. The openable portion 15 cab have a different shape to the one shown here. In the same way as described above for a flap, the peripheral region 13 at one end of the openable portion 15 can be wider at one end to reduce scalding risk. Other features described above in respect of a flap can be applied to the removable openable portion shown in Figure 13. For example: a width of the peripheral region 13 can vary around the perimeter of the openable portion 15; a width of the openable portion can reduce at one end to reduce opening force.

In the above examples, cut lines 11, 12 are formed in the laminate 10. Figure 14A shows a cross-section through one of the layers (outer layer 38 or inner layer 31) and a plan view of the same layer. Figure 14A shows a cut line 11, 12 which is continuous along the surface, as shown in the plan view. The cut line extends fully through the layer, as shown in the cross-section A-B. As there is a continuous cut fully through the layer, the layer will easily separate along the cut line 11, 12.

Figures 14B-14D show some other examples of cut lines 11, 12 which can be formed in one of the layers (outer layer 38 or inner layer 31) of the laminate 10. Each of Figures 14B-14D show a cross-section through the layer and a plan view of the same layer. The example cut lines shown in Figures 14B-14D can provide improved evidence of when the package has been tampered with. One of the cut lines 11, 12 can use a cut line shown in one of the Figures 14B-14D. Alternatively, each of the cut lines 11, 12 can use a cut line shown in one of the Figures 14B-14D. The same type of cut line, or a different type of cut line, can be used for each of the cut lines 11, 12.

Figure 14B shows a cut line 11, 12 which is discontinuous along the surface, as shown in the plan view. This type of cut line is a perforated cut line. This type of cut line is an example of a line of weakness. The cut line comprises non-perforated portions 61 where the layer has not been cut and remains intact, as shown in the cross-section A-B. The cut line also comprises perforated portions 62 where the cut line extends fully through the layer, as shown in the cross-section C-D. The layer is weakened along the cut line. When a force is applied to the cut line by applying an opening force to the lid, the force will rupture the non-perforated portions 61 and the layer will separate along the cut line 11,12.

Figure 14C shows a cut line which is continuous along the surface, as shown in the plan view. The cut line extends partially through the layer, as shown in the cross-section A-B. This type of cut line is a score line or scribe line. This type of cut line is an example of a line of weakness. The layer is weakened along the cut line. When a force is applied to the line of weakness by applying an opening force to the lid, the force will rupture the cut line.

Figure 14D shows a cut line which is continuous along the surface, as shown in the plan view. The cut line extends partially through the first layer. The depth of the cut varies along the cut line. Two cross-sections are shown. At cross-section A-B the cut extends a first depth into the layer. At cross-section C-D the cut extends a second depth into the layer. The second depth is greater than the first depth. This type of cut line can be called a crenellated line. The line can alternate between the cut depths shown in the two cross-sections along the length of the line. The first depth may be zero, such that the line has some portions which are not cut at all, and some portions where the cut line extends partially into the layer. The layer is weakened along the cut line. When a force is applied to the line of weakness by applying an opening force to the lid, the layer will separate along the line of weakness.

In any of the examples, the cut lines 11, 12 may be formed by a laser cutting machine, or by a die cutting machine. The cut line may be formed in one of layers 31, 38 before laminating the layers 31, 38 together. Alternatively, it is possible to form the cut line 11,12 after lamination of the layers 31, 38.

There are various possibilities for the type(s) of adhesive used between layers 31 and 38. A first option is to use a single type of adhesive may be used between the layers 31, 38 across the entire extent of the layers. For example, only a non-permanent adhesive (such as a re-adherable adhesive) is provided between the layers 31, 38. A second option is to use a single type of adhesive between the layers 31, 38 across the entire extent of the layers, and to vary the bond strength in different regions. In the peripheral region 13, where the layers are required to peel apart, the bond strength is a first value. In other regions, where the layers are not required to peel apart, the bond strength is increased above the first value. Optionally, in a part of the peripheral region 13 where the layers are required to separate more easily, such as shown in Figure 8, the bond strength can be reduced below the first value. A third option is to use a non-permanent adhesive (e.g. a re-adherable adhesive) only between the peripheral portion 13 of the second layer and the first layer, and to use a permanent adhesive elsewhere between the first layer and the second layer.

In any of the examples of the package, the non-permanent adhesive can be an oven grade PSA.

The package may carry printing. Figure 15 shows two ways in which the package may be printed. The printing may be provided 72 on an external face of the upper (outer) layer 38. Alternatively, the printing may be provided 73 on an inner face of the upper (outer) layer 38. The outer layer 38 can be reverse printed before the outer layer 38 is laminated to the inner layer 31. Advantageously, the printing 73 can be restricted to a region of the laminate sheet within the cut line 12, or within a region which is offset from the cut line 12 by a defined distance. This can help prevent any migration of chemicals used for the printing into the interior of the package, as the printing will remain within the laminated region of the package. A package having two layers has been described above. It is possible to add one or more further layers to the laminate. The additional layer(s) may be located on the inside or outside of the laminate.

The laminate can be supplied in the form of a web or reel of laminate material. The web is a continuous length of laminate material. The web can be divided into individual pieces to provide the laminate sheet 10 for an individual package. A method of manufacturing an ovenable package comprises providing an ovenable laminate film of the kind described above. The ovenable laminate film is formed into a package. The package is then sealed along at least one side. After filling the package with contents, the package is fully sealed. The laminate may be formed Into a package at a different location to where the laminate is formed. A method of manufacturing an ovenable laminate film for use in forming an ovenable package comprises providing an ovenable first layer and providing an ovenable second layer. The first layer is laminated to the second layer to form an ovenable laminate film. An openable portion is formed in the laminate film by forming a first cut line in the first layer but not in the second layer. The openable portion is formed in the laminate film by forming a second cut line in the second layer but not in the first layer, the second cut line defining an access aperture, wherein the second cut line is offset from the first cut line by a peripheral region of the second layer. The laminating uses a non-permanent adhesive between at least the peripheral portion of the second layer and the first layer.

The package described above is in the form of a bag. The package can take the form of a pouch or other enclosure. Figures 16A and 16B show a pouch with an openable portion 15. Any of the features described above in connection with a bag can be applied to a pouch. In this example, the pouch comprises a front panel (shown) and a back panel which are sealed along the side edges and top edge. Depending on the type of pouch, the front face and back face may be sealed together along the bottom edge, or sealed to a gusset panel. Another type of pouch may have one or more additional panels. Any other type of pouch is possible. In Figure 16A the openable portion 15 is formed in a panel of the pouch with the distal end 15A furthest from the top edge 3. The openable portion hinges about the top edge of the pouch. In Figure 16B the openable portion 15 is formed in a panel of the pouch such that the distal end is nearest to the top edge 3 of the pouch.

It will be understood that the benefits and advantages described above may relate to one embodiment or may relate to several embodiments. The embodiments are not limited to those that solve any or all of the stated problems or those that have any or all of the stated benefits and advantages.

Any reference to 'an' item refers to one or more of those items. The term 'comprising' is used herein to mean including the method blocks or elements identified, but that such blocks or elements do not comprise an exclusive list and a method or apparatus may contain additional blocks or elements.

The steps of the methods described herein may be carried out in any suitable order, or simultaneously where appropriate. Additionally, individual blocks may be deleted from any of the methods without departing from the spirit and scope of the subject matter described herein. Aspects of any of the examples described above may be combined with aspects of any of the other examples described to form further examples without losing the effect sought.

It will be understood that the above description of a preferred embodiment is given by way of example only and that various modifications may be made by those skilled in the art. Although various embodiments have been described above with a certain degree of particularity, or with reference to one or more individual embodiments, those skilled in the art could make numerous alterations to the disclosed embodiments without departing from the spirit or scope of this invention.

Claims

1. An ovenable package comprising: an enclosure formed of an ovenable laminate film, the ovenable laminate film comprising at least: a first layer; and a second layer inside the first layer; an openable portion of the enclosure which is openable to define an access aperture to an interior of the enclosure, the openable portion defined by: a first cut line formed in the first layer but not in the second layer; a second cut line formed in the second layer but not in the first layer, the second cut line defining the access aperture, wherein the second cut line is offset from the first cut line by a peripheral region of the second layer; a non-permanent adhesive between at least the peripheral portion of the second layer and the first layer; wherein the package is openable by separating the first layer of the openable portion from the second layer of the openable portion in the peripheral region.

2. An ovenable package according to claim 1 wherein the non-permanent adhesive is a re-adherable adhesive and wherein the openable portion can be reclosed to put the package into a ventable state, wherein the ventable state permits venting of gas from an interior of the enclosure between the first layer and the peripheral region of the second layer.

3. An ovenable package according to claim 1 or 2 wherein the openable portion has a first region which is intended to be grasped by a user, wherein a width of the peripheral region varies around a perimeter of the openable portion, and wherein the width of the peripheral region is greatest proximate the first region.

4. An ovenable package according to claim 3 wherein the width of the peripheral region proximate the first region is at least three times, optionally at least four times, greater than the width of the peripheral region at other points around the perimeter of the openable portion.

5. An ovenable package according to claim 3 or 4 wherein a maximum width of the peripheral region proximate the first region is at least 3cm, optionally at least 4cm, optionally at least 5cm.

6. An ovenable package according to any one of the preceding claims wherein the openable portion has a first region which is intended to be grasped by a user, wherein the non-permanent adhesive is a re-adherable adhesive and wherein an adhesive bond strength of the re-adherable adhesive in the peripheral region varies around a perimeter of the openable portion, and wherein the adhesive bond strength in the peripheral region at a point around the perimeter of the openable portion, spaced from the first region, is less than the adhesive bond strength in the peripheral region proximate the first region.

7. An ovenable package according to any one of the preceding claims wherein the openable portion has a first region which is intended to be grasped by a user, wherein a width of the openable portion varies along a length of the openable portion, and wherein the width of the openable portion has a minimum value at the first region.

8. An ovenable package according to claim 7 wherein a width of the openable portion decreases along a length of the openable portion, the width of the openable portion having a minimum value at the first region.

9. An ovenable package according to claim 8 wherein the openable portion has a substantially triangular shape.

10. An ovenable package according to any one of the preceding claims with a set of corners, wherein the first cut line extends between a first corner and a second corner of the package.

11. An ovenable package according to claim 10 wherein the package is rectangular and wherein the first corner and the second corner are opposing ends of one side of the rectangular package.

12. An ovenable package according to claim 10 or 11 wherein a width of the peripheral region varies around a perimeter of the openable portion, and wherein the width of the peripheral region Is least proximate the first corner and the second corner.

13. An ovenable package according to any one of the preceding claims wherein the nonpermanent adhesive is a re-adherable adhesive and wherein the re-adherable adhesive Is more strongly attached to the first layer than the second layer such that the re-adherable adhesive Is carried by the first layer when the first layer is separated from the second layer.

14. An ovenable package according to any one of the preceding claims wherein the openable portion Is a flap, the first cut line and the second cut line each defining an open path with a respective first end point and a respective second end point.

15. An ovenable package according to any one of claims 1 to 13 wherein the first cut line and the second cut iine each form a dosed path.

16. An ovenabie package according to any one of the preceding claims wherein only a non-permanent adhesive is provided between the first layer and the second layer.

17. An ovenable package according to claim 16 wherein a bond strength of the nonpermanent adhesive is lower on the peripheral portion of the second layer compared to elsewhere on the second layer.

18. An ovenable package according to any one of claims 1 to 15 wherein the nonpermanent adhesive is only provided between the peripheral portion of the first layer and the second layer, and a permanent adhesive is provided elsewhere between the first layer and the second layer.

19. An ovenable package according to any one of the preceding claims wherein the laminate film is printed on an outer face of the first layer.

20. An ovenable package according to any one of claims 1 to 18 wherein the laminate film is printed between the second layer and the first layer.

21. An ovenable package according to any one of the preceding claims in the form of an ovenable bag.

22. An ovenable package according to any one of claims 1 to 20 in the form of an ovenable pouch.

23. An ovenable laminate film for forming an ovenable package, the ovenable laminate film comprising at least: a first layer; and a second layer inside the first layer; an openable portion which is openable to define an access aperture, the openable portion defined by: a first cut line formed in the first layer but not in the second layer; a second cut line formed in the second layer but not in the first layer, the second cut line defining the access aperture, wherein the second cut line is offset from the first cut line by a peripheral region of the second layer; a non-permanent adhesive between at least the peripheral portion of the second layer and the first layer; wherein the openable portion is openable by separating the first layer of the openable portion from the second layer of the openable portion in the peripheral region.

24. A method of manufacturing an ovenable package comprising: providing an ovenable laminate film according to claim 23; forming the ovenable laminate film into a package; sealing the package.

25. A method of manufacturing an ovenable laminate film for use in forming an ovenable package comprising; providing an ovenable first layer; and providing an ovenable second layer; laminating the first layer to the second layer to form an ovenable laminate film; forming an openable portion in the laminate film by: forming a first cut line in the first layer but not in the second layer; forming a second cut line in the second layer but not in the first layer, the second cut line defining an access aperture, wherein the second cut line is offset from the first cut line by a peripheral region of the second layer; wherein the laminating uses a non-permanent adhesive between at least the peripheral portion of the second layer and the first layer.