The present invention relates to food packaging, more particularly the present invention relates to vacuum packed food products, such as meat, fish and cheese.

Conventionally, food products such as meat and fish sold in supermarkets are packaged in a rigid plastic tray which is covered with cling film or a lidding film. The former option is relatively inexpensive but does not provide the sufficient shelf life from the packaging of the product to the end consumer and lidding films are increasingly favoured.

Another type of packaging adopted by food packers is based on vacuum sealing technology, in which the food product is vacuum sealed into a plastic skin film. The gas free environment extends the shelf life of the product and the end consumer is able to readily see the shape, dimensions and state of the product thus packed. Typically, product specifications are printed onto an adhesive paper label which is then glued directly onto the skin film. Such labels are unprotected and tend to be easily damaged and scratched so that the information printed thereon becomes unreadable. In addition, such labels create a cheap-looking appearance which may render the product unattractive to the end consumers.

To improve the presentation of vacuum sealed products, the product can be placed onto a flat support, then a plastic skin film is applied around both the product and the support. Firstly, the support can be a piece of laminated cardboard, which provides no substantive rigidity. In addition, despite the lamination, the cardboard has a tendency to absorb moisture from the product itself and from outside, thereby becoming soggy and soft. Printed labels placed onto the skin film or the cardboard suffer the same disadvantages as described above.

Cardboard backings have been replaced with plastic trays, generally comprising a base and sidewalls extending from the base. The trays can be closed with a lidding film as described above or vacuum sealed. Such plastic trays are sufficiently rigid to provide suitable support. However, rigid plastic trays are heavy and shaped so that, even when the empty trays can be nested into one another, considerable space is required for storage and transport.

It is an object of this invention to mitigate problems such as those described above. According to a first aspect of the invention, there is provided a process for packaging an article comprising the steps of providing a foldabie blank, placing the article onto the folded blank and vacuum sealing the article and the blank with a plastics film. Preferably, in its unfolded state, the blank is substantially flat and, in its folded configuration, the blank comprises a base and one or more side walls extending from the base. In a preferred embodiment, the blank, in its folded state, comprises a base and four side walls extending substantially perpendicularly from the base.

The flat blanks are lighter, less bulky and easier to store and transport than rigid plastic trays as they can simply be stacked on top of each other. The blanks can be folded into their intended folded configuration at the point of packing the article. The blanks according to the present invention will typically have a thickness of around 350 microns, compared with a thickness of around 650 microns for conventional rigid trays. Conventional rigid plastic trays, in particular PET trays, are prone to distort during vacuum sealing processes because of the inherent stress of the trays and the industry has encountered many issues in trying to decrease this built-in stress without much success.

In addition, the side wails provide rigidity to the overall structure of the folded blank so that unlike cardboard sheets, the folded blanks will not easily lose their shape. This is particularly advantageous when displaying the packed products on a shelf, where a cardboard supporting a vacuum sealed product will buckle upon itself partly due to the weight of the product and partly because of the lack of rigidity of cardboard material. Furthermore, the blank can be held and supported in its folded state (i.e. with the side wails extending upwards from the base) by the vacuum sealed cover film, in particular at the corner points.

Preferably, the process further comprises the step of forming one or more folding lines in the blank. Preferably, the process further comprises the step of folding the blank about the folding Hne(s). In a preferred embodiment, the blank is substantially rectangular or square and the folding lines are substantially parallel to the lateral and longitudinal sides. The pre-folded lines allow accurate and easy folding of the blank into its folded configuration. The blanks can be folded manually or automatically using a folding apparatus. The folding apparatus may comprise one or more support elements to hold the blank in its folded configuration during the vacuum sealing step. In a preferred embodiment, the plastics film (or skin film) is a multilayer film. Preferably, the multilayer film comprises an external support layer and an internal adhesive or seal layer. The external support layer may comprise one or more layers, depending on the desired film properties and provides protection for the packed article from the outside atmosphere. Hie internal adhesive layer enables the plastics film to adhere onto the blank. Preferably, the plastics film has a thickness of 50-150 microns. Within the context of this invention, the numerical value ranges provided herein include the lowest and highest values. Preferably, the process further comprises the step of forming the fo!dable blank.

Preferably, the blank has a multilayer structure and comprises an internal layer for contact with the article and an external support layer. More preferably, the contact layer and/or the support layer are made of a transparent material. Preferably, the blank further comprises an intermediary print layer (coloured layer) between the internal layer and the external layer.

The internal layer of the blank preferably comprises a seating layer to enable the skin film to be peeled off the blank and to access the packaged product. It is preferred that the blank comprises a sealing layer, rather than the skin film.

Preferably, the process comprises the step of applying one or more layers of ink to form the intermediary print layer. The layers of ink or print may be applied by means of one or more rollers. Typically, around 9-10 colours are available and each colour is applied in turn. Preferably, the process comprises the step of applying one or more internal layers of ink onto the surface of the contact layer facing away from the article, thereby creating the colour pattern to appear on the side of the blank facing the packaged article. Thus, the printed colour pattern and information can be seen through a transparent contact layer. Preferably, the process comprises the step of applying two or more intermediary layers of ink to form a masking layer. Preferably two or three layers of ink are applied to create an opaque masking layer. Preferred colours to create this masking layer are white and silver. The masking layer provides an opaque canvas onto which layers of ink can be applied to create the desired colour pattern or image. Images can be printed on one or both sides of the masking layer.

Preferably, the process comprises the step of applying one or more external layers of ink onto the masking layer, thereby creating the colour pattern to appear on the underside of the blank. Thus, the printed colour pattern and information can be seen through a transparent external support layer.

Preferably, the process further comprises the step of applying a layer of adhesive between the intermediary print layer and lite external support layer. More preferably, the adhesive comprises or consists of ethylene vinyl acetate (EVA).

Preferably, the process comprises the step of applying the external support layer onto the intermediary print layer or the adhesive layer, more preferably by thermo-laminating the external support layer onto the intermediary print layer or the adhesive layer. A preferred material for the external support layer is polyethylene terephthalate (PET). The external support layer may be a monofilm or a multilayer film. The external support layer may consist of a monolayer of PET. Alternatively, the external support layer may comprise a layer of recycled PET between two layers of PET, although the layer of recycled PET may be replaced with another material depending on the desired film properties. Most preferably, the external support layer is a co- extruded multilayer film, for example a co-extruded PET multilayer film.

Preferably, the external support layer is thermo-laminated onto the intermediary print layer or the adhesive layer, at the time of manufacture of the external support layer. Freshly co- extruded film will be naturally hot and this heat can activate the adhesive in the adhesive layer so that no additional source of heat is required.

In a preferred embodiment, the article is a food product, such as meat, fish or cheese. According to a second aspect of the invention, there is provided a foldable blank for use in the process described above which, in its unfolded state, is substantially flat and, in its folded state, comprises a base and one or more side walls extending from the base. Preferably, the blank, in its folded state, comprises four side waits extending substantially perpendicularly from the base.

Preferably, the blank comprises one or more folding lines.

Preferably, the blank comprises an internal layer for contact with the article (a contact layer or internal layer) and an external support layer. More preferably, the internal layer comprises a peelable layer and a backing layer. Most preferably, the internal layer comprises polyethylene. In a preferred embodiment, the interna) layer is a peelabie polyethylene layer.

Preferably, the blank further comprises an intermediary print layer between the internal layer and the external support layer. Preferably, the intermediary print layers comprises one or more layers of ink forming a masking layer, one or more layers of ink forming a colour pattern on a first side of the masking layer, and/or one or more layers of ink forming a colour pattern on the second side of the masking layer.

Preferably, the blank further comprises an adhesive layer between the intermediary print layer and the external layer. Preferably, the layer of adhesive comprises ethylene vinyl acetate (EVA).

Preferably, the external support layer is a multilayer co-extruded film. Preferably, the external support layer comprises or consists of polyethylene terephthalate.The external support layer may be a monofilm or a multilayer film. The external support layer may consist of a monolayer of PET. Alternatively, the external support layer may comprise a layer of recycled PET between two layers of PET. although the layer of recycled PET may be replaced with another material depending on the desired film properties. Most preferably, the external support layer is a co-extruded multilayer film, for example a co«extruded PET multilayer film.

According to a third aspect of the present invention, there is provided a method for manufacturing a blank as described above comprising the step of forming a print or coloured layer, preferably a double-sided printed layer. Preferably, the method comprises the step of forming an internal layer for contact with the article and an external support layer. More preferably, the method comprises the step of forming an intermediary print layer between the internal layer and the external layer. Preferably, the method comprises the step of applying one or more layers of ink to form the intermediary print layer. Preferably, the method comprises the step of applying one or more internal layers of ink onto the surface of the contact layer facing away from the article. Preferably, the method comprises the step of applying two or more intermediary layers of ink to form a masking layer. Preferably, the method comprises the step of applying one or more external layers of ink onto the masking layer.

Preferably, the method comprises the step of applying a layer of adhesive between the intermediary print layer and the external support layer. Preferably, the method comprises the step of thermo-laminating the external support layer onto the intermediary print layer or the adhesive layer, most preferably at the time of manufacture of the external support layer.

Preferably, the method comprises the step of forming one or more folding lines in a flat blank.

The invention will be further described by way of examples and with reference to the drawings and figures, in which

figure 1 is a schematic representation of a blank according to the present invention in its unfolded state:

figure 2 is a schematic representation of the blank of figure 1 in its folded state; and figure 3 is a schematic representation of a article vacuum sealed onto a blank according to the present invention, Referring to figures, there is illustrated a foldable blank 1 according to the present invention which is, in its unfolded state, substantially flat as shown in figure 1 and, in its folded state, comprises a base 2 and one or more side walls 3.4 extending from the base. The blank 1 is foldable along pre-formed folding lines 5. The blank 1 shown in the figures comprises two opposed longitudinal walls 3 and two opposed lateral walls 4.

An article 6 is placed onto the base 2 of the folded blank 1. A vacuum sealing film or skin film 7 is applied and the article 6 and the blank 1 are vacuum sealed together. lite film 7 comprises one or more external layers 7A and the choice of material for each layer 7 A depends on the required properties (e.g. liquid barrier, gas barrier, shrinkability etc). The film 7 also comprises an internal adhesive film 7B so that the film 7 adheres to the blank 1. The blank 1 comprises an internal contact layer S for direct contact with the article 6 to be packaged and with the seal layer 7B of the skin film 7; an intermediary print layer 9, an optional adhesive layer i 0 and an external support layer 11.

In this preferred embodiment, the contact layer 8 has a two-layer structure of polyethylene. The top layer 8A in contact with the article 6 to be packaged and with the seal layer 7B of the skin film 7 comprises a peelable formulation. This is the layer 8A which will be peeled oif when the consumer opens the packaging by peeling off the film 7 from the blank I. The peelable formulation comprises or consists of polyethylene and one or more additives to modify the polyethylene and render the layer 8A peelable from the skin film 7. The second layer 8B is a structural layer to provide support to the peelable formulation of top layer 8 A. This second layer comprises or is made of polyethylene, preferably low density polyethylene (LDPB). Enhanced and controlled peel effect has been observed with this type of two-layer structure, and in particular polyethylene two-layer structure. The overall thickness of the contact layer 8 is preferably around 40 microns.

The intermediary print layer 9 comprises three layers 9A. 9B, 9C. Printing is typically achieved using a range of around 9-10 colours, Each colour is applied in turn, for example by means of rollers. Layer 9A facing the article 6 comprises one or more layers (preferably 3-4 layers) which creates the colour pattern of the surface of the blank 1 facing the article 6. Thus. printed patterns, images and/or information can be read on the article side through the transparent skin film 7 and transparent contact layer 8. Similarly, layer 9C facing away from the article 6 comprises one or more layers (preferably 3-4 layers) which creates the colour pattern of the underside surface of the blank 1. Thus, printed patterns, images and/or information can be read on the underside of the blank 1 through the transparent external layer 11.

Preferred priming methods include digital, gravure and fiexographic printing methods.

Layer 9B is a masking layer positioned between layers 9A and 9C so that layers 9A and layers 9C can be printed on either side of layer 9B. Opacity is achieved by printing two to three colours, for example white-silver or white-silver-white. The blank 1 can therefore have printed information on one side or both sides.

The external support layer 11 can be a monolayer or a multilayer structure. For example, the support layer 11 comprises three co-extruded layers of polyethylene terephthaiate (PET), e.g. a layer 11 B of recycled PET between two layers 11 A, 11C of PET. The choice of materials will depend on the properties required. For example, the middle layer 11 B can comprise colouring or materials with specific properties (gas- or liquid-barrier etc). The overall thickness of the external support layer 11 is in the range of from 350 microns to 400 microns for lighter blank 1. The thickness can be increased to around 600 microns for a premium appearance and robustness.

The blank 1 also optionally comprises a layer of adhesive 10 between the intermediary print layer 9 and the external support layer 11. The adhesive comprises or consists of ethylene vinyl acetate (EVA).

The process for manufacturing a blank 1 according to the present invention will now be described by way of example.

The contact layer 8 is prepared by applying a layer of peelable formulation 8A onto a support layer 8B.

The print layer 9 is printed in three steps, which are carried out substantially simultaneously or in rapid succession in a single process step. Firstly, one or more colours are printed (e.g. using one or more printing rollers) onto the support layer 8B to form the desired colour pattern 9A to show on the article side of the blank 1. Secondly, one or more colours are printed (typically two or three, e.g. white and silver) to form an opaque masking layer 9B, which will separate the colour patterns 9A, 9C on each side of the blank . Thirdly, one or more colours are printed onto the masking layer 9B to form the desired colour pattern 9C to show on the underside of the blank 1. An adhesive layer 10 for example of EVA is applied onto the print layer 9 to affix the external support layer 11. The external support layer 11 for example a PET multilayer film is thcrmo-laminated onto the adhesive layer 10. The EVA layer 10 needs to be heated at temperature between 60 to 100°C. preferably around 90°C to be activated. However, if the thermolamination of the PET film onto the adhesive layer is carried out at the time of manutaciure/co-extrusion of the PET film, then there is no need to apply heat, ^' litis is because the PET film will be naturally hot at the time of manufacture.

The blanks i are cut out and one or more folding lines are formed at the desired locations by conventional means.

In use, a blank 1 with pre-formed folding lines 5 is prepared for example through the manufacturing process described above. The blank 1 is then fed into an automated folding apparatus, which will fold the blank 1 about the folding lines 5 so that the folded blank 1 has a base 2 and four side walls 3,4 extending substantially perpendicularly from the base 2.

The article 6 to be packaged for example meat or fish is placed onto the base 2. The article 6 and the folded blank 1 are then vacuum sealed with a skin film 7, surrounding both the article 6 and the blank 1. If required, the side walls 3,4 are supported in the folded position during the vacuum sealing process. The vacuum sealed film 7 therefore holds the side walls 3,4 in the folded position, in particular at the corner points.

Thus, from the above description, it can be seen that the present invention provides a simple and promising alternative to currently available packaging solutions, in particular in the field of food packaging.

The flat blanks can easily be laid on top of each other, stored and/or transported. The inherent stress of the blanks is lower than that of rigid plastic trays so that the blanks do not distort when the vacuum seal is applied. The blanks provide a more hygienic, more stable support than traditional cardboard backings, with enhanced appearance.

The present invention also otters a printing process in which a masking layer is formed onto which an image can be printed on one or both sides of the masking layer. This presents a more hygienic and less damage prone alternative to printed adhesive paper labels.