Note: Descriptions are shown in the official language in which they were submitted.
CA 02450701 2003-12-12
WO 03/002423 PCT/EP02/05064
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 a.n 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.
CA 02450701 2003-12-12
WO 03/002423 PCT/EP02/05064
- 2 -
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/mz and a thickness of between
0.1 and 1 mm is used. In the case of a non-woven,
CA 02450701 2003-12-12
WO 03/002423 PCT/EP02/05064
- 3 -
polypropylene, polyethylene, polyethylene terephthalate
or polyurethane with a grammage of between 20 and
100 gfm2 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 semi-
rigid 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 semi-
rigid material, the exterior packaging will be
CA 02450701 2003-12-12
WO 03/002423 PCT/EP02/05064
- 4 -
unnecessary, since the aluminiumfplastic 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
CA 02450701 2003-12-12
WO 03/002423 PCT/EP02/05064
- 5 -
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 i7) 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)
CA 02450701 2003-12-12
WO 03/002423 PCT/EP02/05064
- 6 -
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.
