CN1520372A - sealed flexible bag - Google Patents

Abstract

The present invention relates to a sealed flexible cartridge (1) , designed to be extracted under pressure, containing a substance for the preparation of a beverage, consisting of a first (3) and a second sheet (4) of circular, oval or polygonal shape which leave between them a space for the substance (2) and are welded together around their periphery (5), the first sheet (3) being made of a material chosen from filter paper, a non-woven and a semi-rigid material and the second sheet (4) being made of a material chosen from filter paper, a non-woven and a composite, 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 (4) 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 (1).

Description

sealed flexible bag

technical field

The present invention relates to a sealed flexible pouch designed to be removed under pressure and comprising a substance for preparing a beverage selected from the group consisting of roast and ground coffee, soluble coffee, ground coffee and soluble coffee Mixtures, chocolate products, or other dehydrated consumer substances, the flexible pouch includes circular, oval or polygonal first and second sheets with a space for the substance between the first and second sheets, and their Welded together around their perimeter, the first sheet is made of a material selected from filter paper, nonwoven and semi-rigid material and the second sheet is made of filter paper, nonwoven and composite.

Background technique

There are already sealed bags on the market that are opened by the action of pressure rise. Patent EP 512 468 concerns such bags: the problem with such bags is that they require a pointed take-out device that tears the top of the bag and a notch and lift element that opens the bottom of the bag thereby allowing the coffee to flow into the cup. There are also bags made of filter paper such as form the subject of patent EP 272 432: the problem with these bags is that the water flows too quickly into the bottom of the coffee without the pressure rising significantly, resulting in not leaving a lot of foam on the coffee.

Contents of the invention

The purpose of the present invention is to enable the user to obtain a bag that requires cheap and simple means to remove the bag, leaving a large amount of good quality foam on top of the coffee.

The invention also relates to a sealed flexible bag according to the preamble of claim 1, wherein the first sheet allows water to pass through it at atmospheric pressure and is torn by tearing means, and the second sheet only Water is passed through it with an overpressure of between 0.1 and 3 bar achieved.

The object of the present invention is therefore to obtain a bag that is not homogeneous for the substance to be withdrawn surrounding between the first and second sheets. The second sheet must hold the water so that it has time to wet and expand the coffee grains: this delay facilitates the extraction of the coffee and produces a good foam. The duration of this retardation will depend on the water supply pump, that is to say will depend on the pressure which will rise in the bag. Typically, the retarding effect on an overpressure of 1 to 3 bar lasts at the level of one second. Of course, due to the increased pressure, a support plate will be required under the second sheet of the bag during removal.

If the bag contains coffee, the roast and ground coffee is simply placed in the bag or compacted. The amount of coffee contained can vary between 5 and 10 grams.

If the first sheet is made of filter paper or non-woven, the water will simply flow by gravity to the bottom of the coffee. On the other hand, if the first sheet is made of semi-rigid material, tearing means will be required to open said first sheet, for example using the device described in patent EP 242 556 . In the case of filter paper, paper with a grammage of 15-30 g/m ² and a thickness between 0.1-1 mm is used. In the case of nonwovens, polypropylene, polyethylene, polyethylene terephthalate or polyurethane with a grammage of 20 to 100 g/m ² is used. In the case of semi-rigid materials, aluminum with a thickness of 20 to 100 micrometers, single or multilayer plastics optionally with an oxygen barrier such as EVOH or PVDC, optionally with an oxygen barrier such as EVOH or PVDC is used For example cardboard, aluminium, plastic or multilayer film of cardboard, plastic.

In a first embodiment, the second sheet comprises areas of weakness which open when the pressure inside the bag reaches a value between 0.1 and 3 bar. The expression "area of weakness" is understood to mean a prefabricated area. These areas are likewise filter papers, nonwovens or even plastic sheets.

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

In both embodiments, the first sheet may be made of filter paper and nonwoven or of semi-rigid material. In both cases, the bag must have an outer packaging since it is not wrapped in a material that forms an oxygen barrier.

In a third embodiment, the second sheet is an aluminum/plastic composite. The expression "aluminum/plastic composite" is understood to mean an aluminum sheet with a prefabricated plastic sheet on top. In this case, if the first sheet is filter paper or nonwoven, an outer wrap will be required. On the other hand, if the first sheet is made of a semi-rigid material, no outer wrapping will be required since the aluminum/plastic layer prevents the passage of oxygen.

In a fourth embodiment, the second sheet comprises a removable cover and a layer which allows water to pass therethrough at a pressure between 0.1 and 3 bar and is made of filter paper or nonwoven. In the latter case, no external packaging is required.

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

In a sixth embodiment, the second sheet is made of heat-treated nonwoven.

Description of drawings

Additional explanations will be given with reference to the accompanying drawings, in which:

Figures 1 and 2 are schematic representations of first and second embodiments of bags of the present invention;

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

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

Fig. 5 is a schematic representation according to a fourth embodiment.

Detailed ways

In the bag 1 of Fig. 1, roast and ground coffee 2 is packed 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 places around the perimeter of the bag. The first sheet allows water to pass through it at atmospheric pressure, while the second sheet, also made of filter paper, includes weak areas so that during extraction the coffee is firstly moistened well, then expands well and the liquid coffee only Outflow when an overpressure of 1 bar level is reached in the bag. There is thus a retardation effect during the passage of the coffee, which causes the coffee to retain a large amount of high-quality foam. With this bag it is possible to use a take-out system without any sharp points, which simply has the means to accommodate the bag in a well-sealed manner and enable take-out.

Figure 2 shows a bag 6 packed with ground and roast coffee 7 between two sheets made of nonwoven. The first sheet 8 is made of a nonwoven which allows water to pass through it at atmospheric pressure. The second sheet 9 is made of a non-woven fabric with a tight mesh so that water can pass through it when the overpressure in the bag reaches 1 bar. The two sheets are welded together at 10 around their perimeter. The same removal system can be used for the front bag.

In the case of FIG. 3 , the bag 11 comprises a first sheet 12 made of a semi-rigid material of aluminum and a second sheet 13 made of filter paper. Roast and ground coffee 14 is placed between these two sheets. The sheets are welded together around their perimeter 15 . Take out from this bag for this reason, need needle to pierce the first sheet material, and this needle forms the subject matter of patent EP 242 556 for example. The sheet made of filter paper allows coffee to pass through it when the overpressure inside the bag reaches 1 ba level during extraction.

Figure 4 shows a bag 16 according to a third embodiment. Ground and roast coffee 17 is packaged between a rigid first sheet 18 made of aluminum and a composite formed of aluminum sheet 19 and prefabricated plastic sheet 20 . Sheets 19 and 20 are welded to sheet 18 at 21 . In order to tear the sheet 18, a needle according to the EP patent is required. Sheet 19 has such a thickness that it has no mechanical strength: it functions as an oxygen barrier. The sheet 20 opens when the overpressure in the bag reaches 1 bar. The advantage of this solution is that no external packaging is required.

Fig. 5 shows the bag 22 in the fourth embodiment. Ground and roast coffee 24 is packaged between a rigid sheet 23 and a second sheet formed by a layer 25 of filter paper and a lid 26 . Sheets 25 and 26 are welded to sheet 23 at 27 . For removal, the cover 26 is removed and the bag is placed in the device described in patent EP242556. Also in this case, no external packaging needs to be provided.

abbreviation:

PVDC = polyvinylidene chloride;

EVOH = ethylene/vinyl alcohol copolymer.

Claims (5)

1. A sealed flexible pouch designed to be removed under pressure and comprising a substance for preparing a beverage selected from the group consisting of roast and ground coffee, soluble coffee, a mixture of ground coffee and soluble coffee , a chocolate product or other dehydrated consumer substance, the flexible pouch comprises circular, oval or polygonal first and second sheets with a space for the substance between them and which surround welded together at their peripheries, the first sheet is made of a material selected from filter paper, nonwovens and semi-rigid materials, and the second sheet is made of a material selected from filter papers, nonwovens and composites, It is characterized in that the first sheet allows water to pass through it at atmospheric pressure and is torn by the tearing device, and the second sheet only allows the overpressure achieved during removal of the bag to be between 0.1 and 3 bar Water passes through it. 2. The sealed bag according to claim 1, characterized in that the second sheet comprises a weakened area which opens when the pressure inside the bag reaches a value between 0.1 and 3 bar. 3. The sealed bag according to claim 1, characterized in that the second sheet is made of filter paper or non-woven fabric with a sufficiently tight mesh so as to allow only when a pressure between 0.1 and 3 bar is reached Water passes through it. 4. The sealed bag of claim 1, wherein the second sheet is an aluminum/plastic composite, the plastic sheet being prefabricated. 5. The sealed bag according to claim 1, characterized in that the second sheet comprises a removable cover and a filter paper or non-woven fabric which allows water to pass therethrough at a pressure between 0.1 and 3 bar. layer.

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