AU2002344962A1

AU2002344962A1 - Sealed flexible cartridge

Info

Publication number: AU2002344962A1
Application number: AU2002344962A
Authority: AU
Inventors: Petr Masek; Alfred Yoakim
Original assignee: Societe des Produits Nestle SA
Current assignee: Societe des Produits Nestle SA
Priority date: 2001-06-28
Filing date: 2002-05-07
Publication date: 2003-05-15
Anticipated expiration: 2022-05-07

Description

Sealed flexible cartridge

The present invention relates to a sealed flexible cartridge, designed to be extracted under pressure, containing a substance for the preparation of a beverage chosen from roasted and ground coffee, soluble coffee, a mixture of ground coffee and soluble coffee, a chocolate product or any other dehydrated consumable substance, consisting of a first and a second sheet of circular, oval or polygonal shape which leave between them a space for the substance and are welded together around their periphery, the first sheet being made of a material chosen from filter paper, a non-woven and a semi-rigid material and the second sheet being made of a material chosen from filter paper, a non-woven and a composite.

There are already on the market sealed cartridges which open up owing to the effect of the rise in pressure. Patent EP 512 468 relates to such a cartridge: the problem with these cartridges is that they require a pointed extraction device to pierce the top of the cartridge and recessed and raised elements to allow the bottom of the cartridge to be opened and thus allow the coffee to flow into the cup. There are also cartridges made of filter paper such as that forming the subject of Patent EP 272 432: the problem with these cartridges is that the water runs too quickly onto the bed of coffee, without a large rise in pressure, resulting in a coffee without a good quantity of foam remaining thereon.

It is an object of the present invention to make available to the user a cartridge requiring for its extraction a less expensive and simpler device which nevertheless gives a coffee with a good amount of good- quality foam remaining. The present invention relates to a sealed flexible cartridge according to the preamble of Claim 1, in which the first sheet is such that it allows water at atmospheric pressure to pass through it or by piercing with a piercing means and the second sheet is such that it allows water to pass through it only if an overpressure of between 0.1 and 3 bar is achieved during extraction from the said cartridge.

The object of the present invention is therefore to make available a cartridge which is not homogeneous in terms of the material surrounding the substance to be extracted, namely between the first and second sheet. The second sheet must retain the water so that the said water has time to wet and swell the coffee grains : this delay effect will give good extraction of the coffee and a good foam. The duration of the delay effect will depend on the water feed pump, that is to say it will depend on what the pressure rise in the cartridge will be. Normally, the delay effect for an overpressure of 1-3 bar is of the order of one second. Of course, it will be necessary nevertheless to provide a support plate under the second sheet of the cartridge during extraction, on account of the rise in pressure.

If the cartridge contains coffee, this is roasted and ground coffee either simply placed in the cartridge or compacted. The amount of coffee present may vary between 5 and 10 g.

If the first sheet is made of filter paper or a non- woven, the water will flow into the bed of coffee in the cartridge simply by gravity. On the other hand, if the first sheet is made of a semi-rigid material, a piercing means will be required to open the said first sheet, for example with a device according to Patent EP 242 556. In the case of filter paper, a paper having a grammage of 15 to 30 g/m² and a thickness of between 0.1 and 1 mm is used. In the case of a non-woven, polypropylene, polyethylene, polyethylene terephthalate or polyurethane with a grammage of between 20 and 100 g/m² is used. In the case of a semi-rigid material, aluminium with a thickness of 20 to 100 microns, pure or multi-layer plastic optionally with an oxygen barrier layer, such as EVOH or PVDC, a multi-layer film such as cardboard, aluminium, plastic or cardboard, plastic optionally with an oxygen barrier layer such as EVOH or PVDC is used.

In a first embodiment, the second sheet comprises weakened regions which open when the pressure in the cartridge reaches a value of between 0.1 and 3 bar. The expression "weakened regions" is understood to mean prescored regions. These may also be filter paper, non- woven or even plastic sheet.

In a second embodiment, the second sheet is made of filter paper or of a non-woven with a sufficiently tight mesh to allow water to pass through it only when a pressure of between 0.1 and 3 bar is reached. The expression "sufficiently tight mesh" is understood to mean a low air or water permeability.

In these two embodiments, the first sheet may be either made of filter paper and a non-woven or made of a semirigid material. In both cases, the cartridge must have exterior packaging, as it is not packaged in materials forming an oxygen barrier.

In a third embodiment, the second sheet is an aluminium/plastic composite. The expression "aluminium/ plastic composite" is understood to mean an aluminium sheet with a prescored plastic sheet on top of it. In this case, if the first sheet is filter paper or a non- woven, an exterior packaging will be required. On the other hand, if the first sheet is made of the semirigid material, the exterior packaging will be unnecessary, since the aluminium/plastic layers prevent the passage of oxygen.

In a fourth embodiment, the second sheet is composed of a cover which is removed and of a layer made of filter paper or of a non-woven allowing water to pass through it at a pressure of between 0.1 and 3 bar. In the latter case too, exterior packaging is unnecessary.

In a fifth embodiment, the second sheet is made of filter paper or a non-woven coated with a layer of lacquer.

In a sixth embodiment, the second sheet is made of a non-woven which has undergone a heat treatment.

The rest of the description is given with reference to the drawings in which:

Figures 1 and 2 are schematic representations of the cartridge according to the invention, in the first and second embodiments;

Figure 3 is a schematic representation of the cartridge in one of the two first embodiments;

Figure 4 is a schematic representation according to the third embodiment; and

Figure 5 is a schematic representation according to the fourth embodiment .

In the cartridge (1) according to Figure 1, the roasted and ground coffee (2) is packaged between a first sheet

(3) made of filter paper and a second sheet (4) also made of filter paper. The two sheets are welded together at (5) around the periphery of the said cartridge. The first sheet allows water at atmospheric pressure to pass through it, whereas the second sheet, also made of filter paper, includes weakened regions so that, during extraction, the coffee is firstly well wetted, then it swells well and the liquid coffee flows out only when an overpressure of the order of 1 bar is reached within the said cartridge. There is therefore a delay effect in the passage of the coffee, which results in a coffee having a good volume of high- quality foam, which remains. With this cartridge, it is possible to use an extraction system without any point, simply with means for housing the cartridge in a well- sealed manner and for effecting the extraction.

Figure 2 shows a cartridge (6) with ground and roasted coffee (7) packaged between two sheets of non-woven. The first sheet (8) is a sheet of non-woven which allows water at atmospheric pressure to pass through it. The second sheet (9) is made of a non-woven with a tight mesh allowing water to pass through it when the overpressure inside the cartridge reaches 1 bar. The two sheets are welded together around their periphery at (10) . It is possible to use the same extraction system as for the previous cartridge.

In the case of Figure 3, the cartridge (11) comprises a first sheet (12) made of a semi-rigid material of aluminium and a second sheet (13) made of filter paper. The roasted and ground coffee (14) is placed between these two sheets. These sheets are welded around their periphery (15) . For extraction from this cartridge, a needle is required to pierce the first sheet, for example that forming the subject of Patent EP 242 556. The sheet made of filter paper allows the coffee to pass through it when an overpressure of the order of 1 bar is reached in the cartridge during extraction.

Figure 4 shows a cartridge (16) according to the third embodiment. The ground and roasted coffee (17) is packaged between a rigid first sheet made of aluminium (18) and a composite formed from an aluminium sheet

(19) and a prescored plastic sheet (20) . The sheets

(19) and (20) are welded to the sheet (18) at (21) . To pierce the sheet (18) , the needle according to the aforementioned EP patent is required. The sheet (19) has a thickness such that it has no mechanical strength: its function is to be an oxygen barrier. The sheet (20) opens when the overpressure in the cartridge reaches 1 bar. The benefit of this solution is that it requires no exterior packaging.

Figure 5 shows a cartridge (22) in its fourth embodiment. The ground and roasted coffee (24) is packaged between a rigid sheet (23) and a second sheet formed from a filter paper layer (25) and a cover (26) . The sheets (25) and (26) are welded to the sheet (23) at (27) . For extraction, the cover (26) is removed and the said cartridge is placed in a device according to Patent EP 242 556. In this case too, it is unnecessary to provide exterior packaging.

Abbreviations :

PVDC = polyvinylidene chloride;

EVOH = ethylene/vinyl alcohol copolymer.

Claims

1. Sealed flexible cartridge, designed to be extracted under pressure, containing a substance for the preparation of a beverage chosen from roasted and ground coffee, soluble coffee, a mixture of ground coffee and soluble coffee, a chocolate product or any other dehydrated consumable substance, consisting of a first and a second sheet of circular, oval or polygonal shape which leave between them a space for the substance and are welded together around their periphery, the first sheet being made of a material chosen from filter paper, a non-woven and a semi-rigid material and the second sheet being made of a material chosen from filter paper, a non-woven and a composite, characterized in that the first sheet is such that it allows water at atmospheric pressure to pass through it or by piercing with a piercing means and the second sheet is such that it allows water to pass through it only if an overpressure of between 0.1 and 3 bar is achieved during extraction from the said cartridge.

2. Sealed cartridge according to Claim 1, characterized in that the second sheet comprises weakened regions which open when the pressure in the cartridge reaches a value of between 0.1 and 3 bar.

3. Sealed cartridge according to Claim 1, characterized in that the second sheet is made of filter paper or of a non-woven with a sufficiently tight mesh to allow water to pass through it only when a pressure of between 0.1 and 3 bar is reached.

4. Sealed cartridge according to Claim 1, characterized in that the second sheet is an aluminium/plastic composite, the plastic sheet being prescored.

5. Sealed cartridge according to Claim 1, characterized in that the second sheet is composed of a cover which is removed and of a layer made of filter paper or of a non-woven allowing water to pass through it at a pressure of between 0.1 and 3 bar.