GB2316906A

GB2316906A - Packaging foil

Info

Publication number: GB2316906A
Application number: GB9719269A
Authority: GB
Inventors: Joergen Friis
Original assignee: Danapak AS
Current assignee: Danapak AS
Priority date: 1996-09-10
Filing date: 1997-09-10
Publication date: 1998-03-11
Also published as: ES1041243Y; GB9719269D0; DE29716238U1; ES1041243U; FR2753128B3; DK9600302U3; FR2753128A3

Abstract

When packaging freeze-dried instant foodstuffs, there is a need for a sturdy and strong packaging foil which can resist the sharp edges and which with a gas-proof barrier layer at the same time protects the contents. For this purpose the foil (1) according to the invention is suitable since the substantially axially oriented polypropylene layer (2) provides the foil (1) with the required strength and toughness by a thickness of layer being about 25 percent smaller than that of known polyamide containing foils and since the orientation additionally results in a suitably low tear strength in one direction, the foil may be easily be opened by tearing along the direction of orientation. Inner layer (5) may be an ionomer. Layer 4 may be a decorative layer (e.g. aluminium foil) and layer 3 may be an adhesive layer. This is advantageous to the consumer who will not need much force nor tools for breaking the foil layer.

Description

PACKAGING FOIL The prior art The invention relates to a packaging foil comprising an outer layer and an inner layer for forming a laminate where adjacent inner layers may be welded together for forming a closed packaging and where between the outer layer and the inner layer there may be arranged a decorative layer or a barrier layer.

Numerous types of packaging foils adapted to special requirements of the packaging are known.

This may for example be due to the physical properties of the product making particular demands on the foil.

Where the product for example comprises granulates or granular products which are pointed or sharp-edged, a substantial ultimate strength of the foil is required to ensure that the package is not destroyed or damaged, but remains intact.

In order to achieve adequate ultimate strength of a foil for this purpose it is known to apply polyamide containing foils for the strength layer This will permit the foil to be dimensioned for achieving the required ultimate strength, but this causes the packaging to obtain some adverse properties First and foremost polyamide containing foils are relatively heavy However, this has had to be accepted due to the requirements of ultimate strength Furthermore, the foil has a similarly high tear strength which makes it difficult to open the packaging. Cutting tools will be required for breaking the packaging.

Moreover, the use of biaxially oriented polypropylene layers are known, which however are possibly even more difficult to tear due to the high tear strength of this material.

In cases where such a packaging foil is to be used for packaging freeze-dried instant soups with paste or the like, which are often packed in portions, it is highly disadvantageous that the packaging is difficult to break in use.

The object of the invention It is the object of the invention to remedy these drawbacks, and this is achieved by letting the outer layer of the laminate consist of substantially axially oriented polypropylene. This will provide for the required ultimate strength by a thickness of layer and thus weight being only about 75 percent of the required thickness of similar polyamide containing laminates, and the substantially axial orientation has the advantage that the foil has a low tear strength in one direction, which can be utilised for opening the packaging This simplifies the use of the packaging compared to known biaxially oriented polyamide containing packaging foils.

By the use of the invention there is accordingly achieved an economic advantage due to the reduced weight of packaging and a practical advantage by the opening of the packaging. y using this foil for packaging freeze-dried foodstuffs as disclosed in claim 2, good protection against blows and perforation of the foil is achieved and thus a suitable packaging for such foodstuffs.

By packaging instant soup with pieces of paste or spaghetti as disclosed in claim 3, a sturdy and gas-proof packaging is obtained which easily opens by tearing in one direction.

The drawing An embodiment of the invention will be further described in the following with reference to the drawing wherein fig. 1 is a sectional view of the laminate and fig. 2 is a partial section through a packaging bag.

Description of an embodiment The packaging foil according to the invention may for example be designed as the laminate 1 shown in fig. 1.

The outer layer 2 consists of substantially axially oriented polypropylene having a thickness of between 12 and 70 p depending on the desired strength and toughness of the resulting foil.

On this outer layer 2 there is provided an adhesive 3 in weights of up to 20 g/m2.

A decorative layer 4 adheres to this adhesive layer 3 This may be conventional Al-foil having a thickness of between 5 and 20 p.

To the decorative layer there is finally adhered a polymeric layer such as an ionorneric layer S. lonomers are thermoplastic polymers having an ionic grid structure.

It is transparent and has good tightness properties joust as it is heat-sealable and can be welded at 120'C. It may adhere to the Al-foil 4 as well as to an adjacent ionomeric layer so that a packaging can be closed by heat-sealing by such adjacent polymeric layers.

Fig. 2 shows an example of a packaging bag made by the laminate 1. The outer layer 2 of substantially axially oriented polypropylene ensures a significant sturdiness and thereby protects the packaged product while at the same time the high ultimate strength of the layer provides good resistance to being penetrated or cut by the packaged product. The orientation may advantageously be across the finished packaging such that it is easily opened by tearing the upper part of the packaging The decorative layer may in a generally known manner be provided with printing etc.

Finally, the inner layer, which is the polymeric layer/ionomeric layer 5, permits sealing of the packaging by welding together the layer 5 in a welding seam 6, which may extend along the side edges of the packaging and seal same.

The weight of the finished packaging is substantially lower than that of the previously known polyamide containing packages, and since the foil is easily torn in the direction of orientation, it can by opened without the use of tools.

The foil can be utilised in generally known packing equipment and makes no particular demands on the use in such equipment.

Claims

CLAmS 1. Packaging foil comprising an outer layer and an inner layer for forming a laminate where adjacent inner layers may be welded together for forming a closed packaging and where between the outer layer and the inner layer there may be arranged a decorative layer or barrier layer, which is characterised in that the outer layer consists of substantially axially oriented polypropylene.
2. Packaging foil according to claim 1, c h a r a c t e r i z e d in that the foodstuff is instant soup containing larger components such as pieces of paste or spaghetti.

2. Packaging comprising a packaging foil according to claim 1 and containing sharp-edged and/or pointed foodstuffs such as frozen or freeze-dried foodstuffs.

3. Packaging according to claim 2, containing instant soup which contains larger components such as pieces of pastry or spaghetti.

4. Packaging foil, substantially as herein described with reference to Figure 1 or Figure 2 of the accompanying drawings-.

5. Packaging, substantially as herein described with reference to Figure 1 or Figure 2 of the accompanying drawings Amendments to the claims have been filed as follows 1. Packaging foil comprising an outer layer and an inner layer for forming a laminate where adjacent inner layers may be welded together for forming a closed packaging and where between the outer layer and the inner layer there may be arranged a decorative layer or barrier layer, and where the outer layer consists of substantially axially oriented polypropylene, c h a r a c t e r i z e d in that it is used for packaging sharp-edged and/or pointed foodstuffs such as freeze-dried foodstuffs.