CA2072300C

CA2072300C - A flexible package with a stiffening element and a process for its production

Info

Publication number: CA2072300C
Application number: CA002072300A
Authority: CA
Inventors: Olivier Fond; Petr Masek
Original assignee: Societe des Produits Nestle SA
Current assignee: Societe des Produits Nestle SA
Priority date: 1991-07-05
Filing date: 1992-06-25
Publication date: 2003-05-27
Anticipated expiration: 2012-06-25
Also published as: ATE128692T1; JP3150202B2; MY109148A; CA2072300A1; FI108427B; FI922897A0; AU1841492A; DE69205232D1; BR9202610A; NO922617D0; ZA924490B; EP0524464B1; AU649844B2; DK0524464T3; KR100221342B1; NO922617L; EP0524464A1; FI922897A; MX9203966A; JPH05199938A

Abstract

The present invention provides a pack in the form of a flexible cartridge, which may be open or closed, for the preparation of a beverage. The pack is specially adapted to an extraction machine, e.g., an espresso machine, which is operating by an extraction liquid under pressure. The pack consists of a body, which may be in the form of one having a cavity which is provided with a rim and which contains a powder-form substance for the preparation of the beverage. The pack is closed by a membrane which is applied to the rim of the body. The pack further includes a complementary stiffening element which is independent of the body. The stiffening element may be the membrane. The body may be of a shape which is configured so that the extraction liquid is able to circulate through a layer of the powder-form substance during the extraction through an exact adaption of the cavity to the extraction machine.

Description

2~~23~U
This invention relates to a package in the form of an open or closed flexible cartridge for the preparation of a beverage adapted to extraction machines operating toy fluid under pressure.
There are several reasons for the use of cartridges for the preparation of a beverage from a powderrform substance, above all in the field of espresso type coffees extracted under pressure, namely: hygiene, optimal keeping of the coffee, ease of use, better control of the quality 20 of the coffee obtained and good reproducibility of the extraction conditions.
There are two main versions of these cartridges, namely: open, with the upper and lower faces permeable to allow the extraction fluid to pass through, or closed, opening automatically in the extraction machine.
To preserve the quality of the coffee by protecting it against moisture and oxygen, open cartridges have to be packed in impermeable bags or provided with impermeable peelable covers on both faces. For their part, closed cartridges are made from impermeable materials.
To comply with legislation on the recycling of packagm ing materials in various countries, a new cartridge design needs to be developed using several different materials (paper, card, aluminium, plastic), the cartridge being open or closed.
On the other hand, to satisfy economic and commercial requirements, these various types of cartridges need to be able to be produced on the same packaging machines and to be extracted in the same extraction machines.
Finally, to reduce the consumption of material in the production of cartridges, the cartridges need to be simpli-fied. This may be done, for example, by eliminating the filter at the bottom of the cartridge.
The use for ecological or economic reasons of flexible materials of minimal thickness and/or impermeable to oxygen 2 r~~~~~~~
for the production of cartridges containing, for example, ground coffee and intended to be extracted under 'the pressure of hot water generally involves the problem of providing the cartridges with a predetermined shape allow-s ing proper extraction of the powder-form substance and of maintaining that shape after handling, transport and storage.
Now, to obtain good extraction of these cartridges, the cartridges have to be able exactly to follow the inner shape of the extraction machine to avoid any preferential passage of water beyond the layer, for example of coffee.
A process for the extraction of capsules mac'le of flexible materials is described, for example, in FR PSS 1 537 031 and 2,033,290. This process is attended by numer-ous disadvantages.
First of a11, it is difficult to carry out because the upper and lower faces of the cavity of the machine intended to receive the capsule are provided with a plurality of projections and holes.
Tn addition, the process is neither dependable nor reproducible because it is impossible to obtain all the desired openings under the effect of the water pressure.
This is because, as soan as one or more openings has/have been formed, the pressure in the capsule falls because the liquid is able to flow.
Accordingly, the number and position of the openings are uncertain. This situation can result in poor extrac-tion of the layer of substance because, as the filter is pressed against the lower face, it cannot be drained over its entire surface. Extraction is incomplete and hetero-geneous because of the existence of zones with preferential passages and poorly irrigated and drained zones.
Tn addition, the process in question is not hygienic.
This is because, in view of the plurality of orifices for the passage of water and the high temperature of the ma ~~~r~~~~

chine, deposits of organic materials difficult to eliminate are inevitably formed.
Accordingly, this process is vulnerable to blockages because the successive deposits of organic materials in the plurality of small orifices can contz~ibute towards the gradual blockage thereof. In these circumstances, the quality and regularity of the extractions are affected to an even greater extent.
Finally, the process in question is Lased with a car°
1~ tridge containing a powder-form or liquid basic substance.
In the case of coffee, it can only be soluble coffee which has to be dissolved with water or a concentrated liquid coffee which has to be diluted with water. Neither the process nor the cartridge can be used in the case of ground coffee.
Flt°A°2 617 389 describes a frustoconical cartridge which is provided with a filtering base and which is closed by upper and lower covers. The cartridge in question consists of five parts with the result that its production involves a large number of operations, including two welding steps.
The problem addressed by the present invention was to provide an open or closed cartridge in the shape of a frustum, inverted frustum or hemisphere which would be made predominantly of flexible materials and which would retain its original shape, particularly during extraction, so that extraction would take plane correctly by the passage of the extraction fluid with no preferential flow paths through the layer of powder°form substance, and which could be ex°
traded in conventional espresso machines by means of a suitable adapter or without such a device, In addition, the package would comprise few parts and would therefore be easy to produce.
The package according to the invention consists of a body in the form of a frustoconical, inverted frustoconical or hemispherical cavity which is provided with a rim and which contains a powder-form substance for the preparation of a beverage, and of a membrane applied to the rim of the body.
Tt is characterized in that it comprises a complemen terry stiffening element independent of the body and in that the element is annular or, if the stiffening element is the membrane, is circular so that the extraction fluid is able to circulate through the layer of powder form substance during extraction through exact adaptation of the cavity to the extraction machine.
The advantage of this cartridge in its closed version is that it doss not comprise an actual filter.
Tn a first embodiment, the stiffening element is formed by a frustoconical jacket provided with a rim designed for application to the rim of the body. The cartridge is made up of three parts, namely a body, a jacket and a membrane.
The effect of the jacket is to stiffen the body of the cartridge, although it may also cover a large part of the membrane. However, the jacket must not completely cover the membrane it must all the same allow the passage of the injection needle provided in certain extraction machines.
The jacket may be disposed on the inside or the outside of the body of the cartridge.
Tf, in the first case, the rim of the jacket is of the same size as the rims of the body and the membrane, the jacket is welded thereto on its two faces. Tf the rim of the jacket is shorter than that of the body and the mem-brave, the jacket may be welded thereto on its two faces but, at all events, the body and the membrane are in part directly welded to one another.
If the jacket is made of plastic, its interposition between the body and the membraxie of the cartridge may perform the function of a fusible seal which promotes the fluid-tightness of the cartridge in its closed version.
In cases where the jacket is disposed on the outside of the body of the cartridge, it may be welded at its rim to the rim of the body. The diameter of the membrane may be equal to or larger than that of the body. The membrane is always welded to the rim of the body although, if the rim of the body is shorter, the membrane may also be directly welded in part to the jacket.
In another configuration, projecting ribs may be l0 integrated in the jacket of the cartridge. The jacket, which is made of injection-moulded plastic, has opening ribs on its lower face, in which case the cartridge is in the shape of an inverted frustum.
The opening ribs integrated in the base of the jacket do project, but are neither directly cutting or directly perforating. Tearing of the lower wall of the cartridge on contact with the projecting elements is only possible because the projecting elements allow the lower wall to reach its breaking stress during deformation under the 2o effect of the air and water pressure. The ribs are formed by small linear or sinuous or arcuate fillets which are circular in cross-sectian and more or less flattened or widened slightly in the downward direction and which are arranged radially, concentrically, parallel or perpendic-x5 ularly on the flow grill of the extraction machine and vary in length.
The arrangement of the ribs has been optimized to allow uniform distribution of the flow zones of the ex-tract, i.e. better irrigation and hence better extraction 30 of the layer of powder-form substance and better quality of the extract obtained.
These elements are variable in length according~to their position on the base of the cartridge, the diameter of the lower face and the constituent material c~f the body.
35 Their cross-section is semi-circular, more or less flat-tened or more or less widened in the downward direction.
Their average diameter preferably varies from 0.5 to 5.0 mm. They may also be conical or frustoconical fn cross section. They may vary in number from 4 to 16, depending on the diameter of the lower face.
In the open version, the body and 'the membrane of the cartridge may be made of such materials as filter paper or nanwoven synthetic fibres. The cartridge is then packed in a bag impermeable to oxygen and water vapour so that it has a sufficient storage life pending use.
2n order to increase the stiffness of the cartridge, the wall of the jacket and the wall of the body may be fluted so that they are in the form of concentric annular ribs.
In one variant, the jacket may be perforated arid may have openings in its annular wall in the interests of economy of material.
In a second embodiment relating to a cartridge in the foran of a frustum, inverted frustum or hemisphere, 'the stiffening element is a ring applied to the rim of the body, the cartridge also comprising three parts.
In a third embodiment of a cartridge in the form of an inverted frustum, the stiffening element is formed by a frustoconical collar at the major base of the frustum of the body extended by a flange in the outer radial direc-Lion, the cartridge again comprising three parts.
In a fourth embodiment, the stiffening element is the membrane itself so that the cartridge comprises two parts.
The membrane may be perforated in the open version of the cartridge, which is thus in the shape of a frustum or inverted frustum, and perforated in the closed version which is in the form of an inverted frustum, the perfora-tion being formed, for example, by means of a hollow needle.
In particular variants of the second and third embodi-ments described above adaptable to various sizes of the extraction machine, the body of the cartridge is flexible and laterally and longitudinally deformable which provides for extension of the cartridge during extraction. A
cartridge such as this can be extracted in the majority of commercial espresso coffee machines without requiring an adapter.
In the open version, the cartridge may have a central-ly perforated base. The openings may be large, for example in the form of permanent holes apparently formed in the wall by hot needles or apparently closed in the case of slots. In the latter case, the cartridge may be extracted by means of a specific cartridge holder provided with ribs on the flow grill. Under the effect of pressure, the material deforms at the ribs and the slots formed in the base of the capsule are enlarged to allow the extract to flow. In the case of ground coffee, there is thus a preliminary effect comprising an increase in pressure and compacting and wetting of the coffee.
Depending on the impermeability of the material to oxygen, the cartridge may be wrapped as such when it is closed or may optionally be Backed in bags which are them-selves impermeable to oxygen and which allow storage for ~
to 12 months. In the latter case, the cartridges may be packed in groups, far example of 2 to 10, because - as they are closed - they themselves will keep for a few days, for example for Z to 15 days, after the bag has been opened.
The cartridge comprises two or three parts, namely a flexible body and a stiff membrane or a flexible body and membrane and a stiffening element. The body is frustoconi cal in shape or in the form of an inverted frustum. The cross-section of the body is rounded, in other words it may be circular, oval ar polygonal with rounded edges.
The cartridge according to the invention may be extracted with the device comprising a grill according to g applicants' copending Canadian patent application no. 2,068,067, filed May 6, 1992. The cartridge may also be extracted in a conventional espresso type coffee machine by means of a specific adapter such as described in the copending Canadian patent applications filed by applicants on the same day as the present application under nos. 2,072,324, 2,072,263 and 2,072,289.
In the adaptable embodiments mentioned above where the body is deformable and extendable, extraction may be carried out without modification of the various components of the extraction machine, i.e. without any need for an adapter.
The extraction machines according to the patent applications cited above enable this simplified cartridge to be extracted under good conditions. The cartridge opens automatically in the extradition machine and, after use, may be withdrawn easily and integrally with a minimum of waste grounds or. packaging material.
The present invention also relates to a process for the production of the package in which the body of the cartridge comprising a rim is thermoformed or stamped from a first film, the body thus formed is filled with a powder-form composition for a beverage in a stream of inert gas, after which the membrane formed from a second film is sealed to the body of the cartridge.
The process is characterized in that an annular stiffening element or, if the stiffening element is the membrane, a circular stiffening element is placed on the rim of the body and sealed to the body and optionally to the membrane.
The invention is described in more detail in the following with reference to various embodiments of cartridges illustrated by way of example in the accompanying drawings, wherein:
Figures l, 2, 3 and 4 are diagrammatic medial sections through various frustoconical or inverted frustoconical cartridges with a jacket.
Figure 5 is a plan view of the jacket of an inverted frustoconical cartridge with opening ribs integrated in the jacket.
Figures 6 and 7 are respectively a section A-A through the cartridge associated with the jacket shown in Fig. 5 and a section 8-B through the jacket shown in Fig. 5.
Figure 8 is a medial diagrammatic section through a frustoconical cartridge.
Figure 9 is a medial diagrammatic section through a cartridge with a circular stiffening element formed by the membrane.
Figures 10 and 11 are medial diagrammatic sections through cartridges with an annular stiffening collar (Fig.
10) or ring (Fig. 11).
Figures 12 to 15 diagrammatically illustrate the production process for the cartridges.
Referring to Figs. 1 to 4, the body 1 and the membrane 2 of the cartridge consist of thin flexible films. The jacket 3 has a frustoconical shape adapted to the body with its stiff, thick wall. Tt is disposed on the inside (Fig.
1) or outside (Fig. 2) of the body and comprises a rim 4 sealed to the rim 5 of the body.
Tn Fig. 3, the jacket 3 partly covers the base 6 of the beady at its periphery. The jacket 3 is fluted in the version shown in Fig. ~ to increase its stiffness.
The cartridge shown in Figs. 5, 6 and 7 comprises radial ribs 7 varying in length which are integrated in the perforated base 8 of the jacket 3.
In the cartridge shown in Fig. 8, which is frusto-conical in shape, the jacket 3 covers almost the entire upper face 9 of the body, but leaves a central opening 10 for the passage of the hollow needle of the extraction machine.
In the versions shown in Fig. 9 relating to a closed cartridge and in Figs. 10 and 11 relating to open car-tridges, the stiffening element is either the membrane 2 (Fig. 9) or a frustoconical annular collar 21 disposed on the major base of the frustum of the body 1 extended by a rim 12 in the outer radial direction (Fig. 10) or a wide ring 13 an the rim of the body. In the versions shown in Figs. 10 and 11, the cartridges are extendable in diameter and height so that they may be used 3.n the majority of commercial espresso coffee machines without necessitating modification of the filter holders of the machines.
These cartridges are open, i.e. the flexible walls of the body and membrane have perforations 14 and 15.
In a variant (not shown), a closed cartridge may comprise a collar or a ring as described above as the stiffening element.
The cartridges shown in Figs. ~. to 9 may be of the open or closed type.
In the closed version, the thin walls of the body 1 and the membrane 2 may be made of the following constituent materials of a barrier layer:
aluminium, preferably 20 to 50 ~Cm thick, with a heat-sealable laac~uer, - multilayer composite of plastic, for example polyethy lene, polypropylene, polyamide, polystyrene or poly ester, and a plastic material impermeable to oxygen, for example a copolymer of vinyl alcohol and ethylene optionally filled with silica or metallized, or poly-vinylidene chloride, - multilayer composite of aluminium, preferably 8 to 20 ~tm thick, paper weighing 20 to 60 g/mx and a plastic material such as mentioned above, preferably 20 to 60 dam thick.
The thick-walled jacket (Figs. 1 to 8) or the thick membrane (Fag. 9) may be made of a thermoformed or injec tion-moulded plastic material such as mentioned above, for example between 0.3 and 1 mm in thickness.
It may consist of a multilayer composite of card, for exempla weighing 100 to 300 g/mz, and a plastic material such as mentioned above between 20 and 60 dam in thickness.
In the open version, the body 3. and the membrane 2 may consist, for example, of filter paper or of a composite of perforated or woven or nonwoven polyester or polypropylene, for example weighing 15 to ~0 g/mx. The jacket 3 and the thick-walled membrane 2 are made of a material such as mentioned above.
In the case of a stiffening element in the form of a collar or ring, for example as illustrated in Figs. 10 and 12, the thin walls of the body 1 and the membrane 2 are made of a plastic material such as mentioned above, but without a barrier layer, and are perforated (in the case of Figs. 10 and 11). The body 1 and the membrane 2 may also be made of filter paper or woven or nonwoven synthetic fibres. The thicker stiffening elements are made either of a plastic material or of cardboard or a multilayer plas tic/card composite.
7Cn the versions shown in Figs. 1 to 9, a layer of filter paper or woven or nonwoven synthetic fibres may be provided between the substance to be extracted and the lower inner wall of the cartridge in order completely to eliminate the risk of dispersion of grounds after ex~trac-tion. This layer may optionally be bonded to the wall.
As shown in Fig. ~.2, the process for the production of a cartridge comprises the following steps:
The body 1 is formed at 16 by stamping with a die and a cavity block and the rim is formed by folding at 17.
At 18, tine jacket made beforehand by thermoforming, injection moulding or moulding is placed inside the cavity 'thus formed.
ground coffee 20 is measured out and tamped at 19 and, at 21, the membrane is welded to the rim of the jacket which in turn is welded to the rim of the body. The alterations of measuring, tamping and welding of the mem-brane are serried out under nitrogen. This process may be used for the production of the cartridge shown in Fig. 1.
Referring to Fig. 13, the jacket 3 is formed at 22, fox example by thermoforming or injection moulding if it is made of plastic or by forming if it is made of card. At 23, the body 1 is stamped out inside the jacket deposited beforehand in a cavity block. Ground coffee 20 is measured out and tamped at 24 and the rim 5 of the body is formed by folding at 25. At 26, the membrane 2 is welded to the rim 5 of the body and the rim 5 is in turn welded to the jacket 3. In a variant (not shown), the body is not formed in the jacket 3, instead a cover is planed at the bottom of the jacket and welded, the coffee is measured out and the membrane is welded. The operations of measuring out, tamping and welding of the membrane are carried out under nitrogen. The illustrated process is used for the produc-tion of the cartridges shown in Figs. 2, 3, ~, 6 and 8.
In Fig. 14, the process comprises the steps of thermo-forming the body at 27, measuring out and then tamping the coffee at 28 to the rim 29, and at 30 cutting out the thickmem-brane 2 and welding the thick membrane to the rim 29. The cartridge is cut out at 31.
The process illustrated in Fig. 1.5 differs from that shown in Fig. 1~ solely in the fact that the body 32 is thermoformed, an annular stiffening collar 11,12 is welded to the body, the coffee is introduced and tamped and the membrane 2 thermoformed beforehand is welded to the rim 5 of the body. Conversely, the outer radial part of the collar may of course be applied to the rim of the body and the membrane may be welded beforehand of thereafter. The base of the body and the membrane are then perforated at their centres (14,15) at 33.
In Fig. 16, the process is carried out as in Fig. 15, ~~.~.~3~~

except that a stiffening ring 13 is applied to part of the rim of the body.
In all the versions described in this specification, the cartridge according to the invention may vary in size according to the desired volume of beverage. ~'or example, the dose of coffee may vary between 5 and 20 g, the di-ameter of the cartridge is between 2.5 and 8 cm and the thickness of the layer of coffee is between 10 and 25 mm.
The cartridge is filled with a powder-form composition for the preparation of a beverage. This substance is preferably roasted and ground coffee, but may also be tea, soluble coffee, a mixture of ground coffee and soluble coffee or a chocolate-flavoured product.
In every case, the extraction fluid will be directed in a vertical stream to pass through the entire layer of powder-form composition without any danger of lateral flow paths being created.

Claims

1. A pack in the form of a flexible cartridge for the preparation of a beverage, said pack being configured to an extraction machine which is operated by an extraction liquid under pressure, said pack consisting of a body having a cavity which is provided with a rim and which contains a powder-form substance for the preparation of said beverage, said pack being closed by a membrane which is applied to the rim of the body, said pack further comprising:
a complementary stiffening element which is independent of said body;
said stiffening element being of a shape which is configured so that said extraction liquid is able to circulate through a layer of said powder-form substance during said extraction through an exact adaption of said cavity to said extraction machine.

2. The pack as claimed in claim 1, wherein said pack is an open flexible cartridge.

3. The pack as claimed in claim 1, wherein said pack is a closed flexible cartridge.

4. The pack as claimed in claim 1, claim 2 or claim 3, wherein said body has a frustoconical cavity therein.

5. The pack as claimed in claim 1, claim 2 or claim 3, wherein said body has an inverted frustoconical cavity therein.

6. The pack as claimed in claim 1, claim 2 or claim 3, wherein said body has a hemispherical cavity therein.

7. The pack as claimed in any one of claims 1 to 6, wherein said stiffening element is configured to be circular.

8. The pack as claimed in any one of claims 1 to 6, wherein said stiffening element comprises a circular said membrane.

9. The pack as claimed in any one of claims 1 to 3, wherein said stiffening element is formed by a frustoconical jacket which is disposed on the inside of said body.

10. The pack as claimed in any one of claims 1 to 3, wherein said stiffening element is formed by a frustoconical jacket which is disposed on the outside of said body.

11. The pack as claimed in claim 9 or claim 10, wherein said cartridge is an inverted frustum, and wherein an inverted frustoconical jacket thereof includes projecting opening ribs on its lower face.

12. The pack as claimed in any one of claim 1 to 3, wherein said body is in the form of a frustum, and wherein said stiffening element is a ring which is applied to said rim of said body.

13. The pack as claimed in any one of claim 1 to 3, wherein said body is in the form of an inverted frustum, and wherein said stiffening element is a ring which is applied to said rim of said body.

14. The pack as claimed in any one of claim 1 to 3, wherein said body is in the form of a frustum, and wherein said stiffening element is a frustoconical collar at the major base of said frustum of said body, extended by a rim in an outer radical direction, and wherein said stiffening element includes a ring which is applied to said rim of said body.

15. The pack as claimed in any one of claim 1 to 3, wherein said body is in the form of an inverted frustum, and wherein said

16 stiffening element is an inverted frustoconical collar at the major base of said inverted frustum of said body, and wherein said stiffening element includes a ring which is applied to said rim of said body.

16. The pack as claimed in any one of claims 1 to 3, wherein said body is in the form of an inverted frustum and wherein said stiffening element comprises said membrane.

17. The pack as claimed in any one of claims 1 to 3, wherein said body is in the form of a hemisphere and wherein said stiffening element comprises said membrane.

18. The pack as claimed in any one of claims 1 to 17, wherein said body is deformable so that said cartridge adapts itself to different extraction machines.

19. A method for the production of the pack claimed in any one of claims 1 to 18, which method comprises:
thermoforming said body of said cartridge from a first film, and whereby said cartridge also includes a rim;
filling said body thus formed with a powder-form composition for a beverage in a stream of inert gas;
then forming said membrane from a second film;
sealing said membrane to said body of said cartridge;
placing a stiffening element on said rim of said body; and sealing said stiffening element to said body.

20. A method for the production of the pack as claimed in any one of claims 1 to 18, which method comprises:
stamping said body of said cartridge from a first film, and whereby said cartridge also includes a rim;
filling the body so formed with a power-form composition for a beverage in a stream of inert gas;

forming said membrane from a second film;
sealing said membrane to said body of said cartridge;
placing a stiffening element on said rim of said body; and sealing said stiffening element to said body.

21. The method as claimed in claim 19 or claim 20, including the step of also sealing said stiffening element to said membrane.

22. The method as claimed in claim 19, claim 20 or claim 21, including the step of forming said stiffening element before shaping of said body.

23. The method as claimed in claim 19 or claim 20, including the step of forming said stiffening element separately from shaping of said body.

24. The method as claimed in any one of claims 19 to 23, including the step of perforating the bases of said body and of said membrane, thereby to produce an open cartridge.

25. The method as claimed in any one of claims 19 to 24, which further comprises: forming slots in a central part of said base of said cartridge.

26. A method for extracting a beverage using an extraction machine and a pack as claimed in any one of claims 1 to 18, comprising disposing said pack in a cartridge holder in said extraction machine;
urging an extracting liquid under pressure through said pack, thereby to extract said beverage; and selecting, as said cartridge holder, a cartridge holder which is formed with ribs on a flow grill thereon;

whereby, in said extracting operation, said slots are closed but become larger under the pressure of the liquid during said extraction;
whereby the material of the base of said cartridge holder deforms at said ribs so that an increase in pressure is established; and thereby said powder-form substance is compacted and wetted before the flow of said extracting liquid.