Daniel (NMN) ABEGGLEN

Nicola (NMN) GALAFFU

Michael Karlheinz HAUSMANN

Field of the invention

The present invention concerns a capsule for the preparation of a beverage in a beverage preparation device. The capsule comprises a cup-shaped body wherein at least said body is shaped from a cellulose pulp-based material.

Background of the invention

Containers or capsules made from a cellulose pulp-based material are known in the field of beverage preparation devices. Cellulose pulp-based materials are also known which are capable of maintaining the qualities of the beverage substance in the capsule, at least for a certain period of time. Single-use capsules for preparing a beverage in a beverage production device are also known.

These cellulose pulp-based single-use capsules provide a potential reduced environmental impact compared to capsules made of other materials.

Known cellulose pulp-based capsules used in beverage preparation devices typic comprise a member enclosing the capsule during the beverage preparation process and the injection of water in the capsule for the preparation of the beverage.

In known paper capsules, it can happen that when the water injection member pierces the dedicated portion of the cup-shaped body of the capsule, this dedicated portion of the cup-shaped body, and often also the entire cup-shaped body, does not retain its shape and for example it collapses inwards.

This can cause the injection member not to pierce the wall of the cup-shaped body or only parti pierce it, this can in some cases block the capsule inside the beverage preparation device and/or cause an incorrect injection of the water and consequently an incorrect dispensing of the beverage.

The present invention aims to improve the ability to be pierced by the known piercing elements of a usual beverage preparation devices, of capsules made of cellulose pulp-based materials.

Summary of the invention

The invention as claimed in claim 1 is a capsule for the preparation of a beverage in a beverage preparation device, comprising: a cup-shaped body, a cover for closing the cup-shaped body, and an annular flange for the cover to seal thereon.

The cup-shaped body comprises: a bottom wall, a tubular lateral wall and the flange. The bottom wall comprises: at least a fluid injection portion, suitable for being pierced by a piercing member of the beverage preparation device, and at least a surrounding portion surrounding said first fluid injection portion. The cup-shaped body comprises a cellulose pulp layer made of cellulose pulp, and an oxygen barrier liner.

According to the invention the stiffness of the cellulose pulp layer of the fluid injection portion is greater than the stiffness of the cellulose pulp layer of the surrounding portion, and the cellulose pulp layer of the fluid injection portion comprises ultrasonically stiffened cellulose pulp.

According to the invention the density of the ultrasonically stiffened cellulose pulp of the fluid injection portion is increased with respect to the density of the cellulose pulp of said surrounding portion.

In a preferred embodiment of the invention the difference between the density DI of the fluid injection portion and the density D2 of the surrounding portions is a value comprised between 0,1% of DI and 20% of DI, that is:

O,1%D1 < (DI - D2) < 20%Dl and more preferably, the difference between the density DI of the fluid injection portion and the density D2 of the surrounding portions is a value comprised between 5% of DI and 10% of DI, that is:

5%D1 < (DI - D2) < 10%Dl.

In a further preferred embodiment, the ultrasonically stiffened cellulose pulp of the fluid injection portion comprises one or more of the following features:

- the amount of the hydrogen bonds and/or the hornification value of the fibres of the ultrasonically treated cellulose pulp of the fluid injection portion is increased with respect to the amount of the hydrogen bonds and/or the hornification value of the non-ultrasonically treated fibres of the cellulose pulp of the surrounding portion, surrounding said fluid injection portion; - the orientation of the fibres of the fibres of the ultrasonically treated cellulose pulp of the fluid injection portion is different from the orientation of the non-ultrasonically treated fibres of the cellulose pulp of the surrounding portion, surrounding said fluid injection portion;

- the water retention value (WRV) of the fibres of the ultrasonically treated cellulose pulp of the fluid injection portion is decreased with respect to the water retention value of the non-ultrasonically treated fibres of the cellulose pulp of the surrounding portion, surrounding said fluid injection portion.

According to another preferred embodiment, only the cellulose pulp layer of the cup shaped body is ultrasonically stiffened, the oxygen barrier layer of the cup shaped body not being ultrasonically treated.

According to a still preferred aspect of the invention the cupshaped body is made of cellulose pulp comprising cellulose fibres in a percentage ranging from 80% to 100% by weight.

In a further preferred embodiment, the thickness of the ultrasonically stiffened cellulose pulp layer of said fluid injection portion is decreased by 20% - 70%, preferably by 50%, with respect to the thickness of the cellulose pulp layer of the surrounding non-ultrasonically treated portions.

According to a still preferred aspect of the invention the oxygen barrier liner comprises a thermoformable polymer.

Preferably but not exclusively, the capsule of the invention is a single use coffee capsule.

According to the invention, the use of a capsule as described before in a beverage preparation device is also disclosed.

In the context of the invention, the term "cellulose pulp" refers to a pulp comprising cellulose fibres in a percentage ranging from 80% to 100% by weight.

The term "cellulose fibres" refers to fibres having a wood and/or a wood free origin. The fibres, by way of non-limiting examples, are: hard wood cellulose fibres, soft wood cellulose fibres, wheat fibres, corn fibres, bagasse fibres, bamboo fibres, hemp fibres, cotton fibres, other similar vegetable or plant fibres, or a combination thereof.

The cup shaped body made of cellulose pulp comprises at least one oxygen barrier liner made of one, preferably several layers.

The oxygen barrier liner is made of a known mono or multilayer polymeric liner, comprising for example a polymer of fossil or non-fossil origin or a BioSource polymer, and is attached to the inner surface of the cellulose pulp cup shaped body of the capsule.

A preferred multilayer barrier liner comprises a core layer having oxygen and/or moisture barrier properties, surrounded by a sealing layer for sealing said barrier liner to the cellulose pulp material.

The oxygen barrier liner, by way of non-limiting examples, comprises one or more of following layers:

- an outermost polymeric layer comprising a biodegradable polymer selected within the list of: polybutylene succinate (PBSA / bioPBS), polybutylene adipate terephthalate (PBAT), starch, cellulose derivates, polylactic acid (PLA), polyhydroxyalcanoates (PHA), or a combination thereof,

- a first tie layer comprising a biodegradable modified or functionalized polyolefin,

- a barrier layer comprising a polymer selected within the list of: butenediol vinyl alcohol copolymer (BVOH), polyvinyl alcohol (PVOH) or a combination thereof,

- a second tie layer comprising a biodegradable modified or functionalized polyolefin,

- an innermost polymeric layer comprising a biodegradable polymer selected within the list of: polybutylene succinate (PBSA), polybutylene adipate terephthalate (PBAT), starch, cellulose derivates, polylactic acid (PLA), polyhydroxyalcanoates (PHA) or a combination thereof. The cover is made in a known material, preferably it is a polymeric film membrane.

The cover may be flat, i.e., non- formed in a three-dimensional shape.

The cover is sealed onto a sealing layer of the cup shaped body opening, in order to close it after filling with an ingredient.

The cup shaped body of the capsule is preferably obtained by moulding in a mould a dry or wet, preferably wet, cellulose pulp.

Preferably, after the cup shaped body of the capsule is moulded the "barrier liner" mentioned above is laminated on the inside and/or outside surface of said body.

Preferably, the barrier to oxygen for both the cover and the cup shaped body is selected to provide a sufficient shelf life depending on the nature of the beverage ingredients. For coffee, for example, the shelf life expected may be of 12 months.

Preferably, the cellulose layer of the cup shaped body, its oxygen barrier liner and/or the cover of the capsule are made of home compostable materials. The capsules according to the invention are normally meant to be recycled in recycling processes that are organized at official recycling facilities according to national regulations (for instance in paper recycling streams, or in general garbage recycling or treatment streams). However, in case the capsule is placed in nature, in a household compostable waste or in a landfill, said capsules are designed with materials that are naturally ready to be degraded by bacteria and in conditions of temperature and humidity that are naturally present in nature. In this way, it is ensured that such capsules will not stay in nature and will naturally disappear within a short period of time (a few weeks in principle) within the conditions defined by home composability standards. More precisely, home composability is now well defined on a national level and mainly based on international standard EN 13432; therefore, they do not require to be further defined in-depth in the present specification. Materials or products compliant with these standards can be recognized by a conformity mark stating their home composability. Some examples of home composability certifications at a national level include, but are not limited to, the following. The certifier TUV AUSTRIA BELGIUM offers such a home composability certification scheme, and DIN CERTCO offers a certification for home composability according to the Australian standard AS 5810. Italy has a national standard for composting at ambient temperature, UNI 11183:2006. In November 2015, the French Standard "NF T 51-800 Plastics - Specifications for plastics suitable for home composting" was introduced. This standard is covered in the DIN CERTCO scheme.

The preparation of the beverage is obtained by mixing of the fluid substance with an ingredient contained in the capsule. Preferably, the ingredients are chosen within the list of roast and ground coffee, compacted or not, soluble powder coffee or leaf tea. Dairy ingredients (e.g., milk or creamer) could also be provided, as well as chocolate, fruit juices, soups, vegetable juices, bouillons, smoothies, purees, coulis, creams, chicory, barley, culinary aid, soup ingredient, infant formula or a combination thereof, in powdered soluble form, liquid concentrated form having various viscosities or in gel form.

Most preferably, the beverage ingredients are roast and ground coffee.

The capsule of the invention may typic interact with a beverage and/or food preparation device, such as by being fed with a diluent (e.g., hot, cold or ambient water) in the container; such diluent mixes, or interacts otherwise, with the beverage ingredients. With the expression "mixing of the diluent with the beverage ingredient(s)" it should be intended that all the ingredients contained in the capsule are in a form which is compatible with a generic mixing operation (dissolution, extraction or infusion) with the diluent to obtain the beverage product. Devices of this type are for example those used for the extraction of traditional Nespresso® capsules. Preferably, the cavity delimited by the capsule body and cover of the capsule is essentially oxygen-free and the empty space is saturated with an inert gas such as nitrogen, carbon oxide and combinations thereof. Preferably, the capsule has an internal pressure of gas above atmospheric pressure, due to the gas contained in the coffee and emanating in the cavity after sealing, such as carbon oxide and dioxide.

Brief description of the drawings

Additional features and advantages of the present invention are described in, and will be apparent from, the description of the presently preferred embodiments which are set out below with reference to the drawings in which:

Figure 1 is a perspective view of a capsule according to the present invention;

Figure 2 is a longitudinal sectional view of the capsule of figure 1;

Figures 2A and 2B are schematic enlarged views of the portions of figure 2 indicated by the arrows W1 and W2, respectively;

Figure 3 is a schematic and partial longitudinal sectional view of the capsule of figure 1 in an intermediate phase of its manufacturing process; and

Figure 4 is a schematic and partial longitudinal sectional view of the capsule of figure 1 when it is enclosed in a capsule enclosing member of a beverage preparation device.

Detailed description of the invention

The capsule shown in figures 1 and 2 comprises a cup-shaped body 1, a cover 2 for closing the cup-shaped body 1, and an annular flange 3 for the cover 2 to seal thereon. The cup-shaped body 1 comprises: a bottom wall 4, a tubular lateral wall 5 and the flange 3. The bottom wall 4 comprises: at least a fluid injection portion 7 (whose area has been highlighted with a dashed line in figure 2) suitable for being pierced by a piercing member 12 (in figure 4 two piercing members are shown) of a beverage device 10 for the preparation of the beverage, and at least a second portion 13A, 13B (in figure 1 two second portions are shown) surrounding said first fluid injection portion 7.

The cup-shaped body 1 comprises a cellulose pulp layer 14 (figure 2A) made of cellulose pulp, and an oxygen barrier liner 15.

According to the invention, the stiffness of the cellulose pulp layer 14 of the fluid injection portion 7 is greater than the stiffness of the cellulose pulp layer 14 of the portions 13A, 13B of the cup shaped body, surrounding said fluid injection portion 7, and said cellulose pulp layer 14 of the fluid injection portion 7 comprises ultrasonically stiffened cellulose pulp. This ultrasonically stiffened cellulose pulp increases the density of the cellulose pulp layer 14 of the fluid injection portion 7 relative to the cellulose pulp layer of the portions 13A, 13B of cup shaped body surrounding said fluid injection portion 7.

Preferably, the difference between the density DI of the fluid injection portion 7 and the density D2 of the surrounding portions 13A, 13B is a value comprised between 1% of DI and 20% of DI, that is:

O,1%D1 < (DI - D2) < 20%Dl; more preferably, the difference between the density DI of the fluid injection portion 7 and the density D2 of the surrounding portions 13A, 13B is a value comprised between 5% of DI and 10% of DI, that is:

5%D1 < (DI - D2) < 10%Dl.

The increased stiffness and consequently the increased density of the fluid injection portion 7 ensure that, during the beverage preparation, the capsule retains its initial shape, in particular when its bottom portions 4 is pierced by the piercing members 12. The stiffness of the fluid injection portion 7 is similar to the stiffness of the corresponding portions of usual plastic or aluminium capsules. According to the invention, "ultrasonically stiffened cellulose pulp" means an ultrasonically treatment of the first cellulose pulp layer 14 of the cup-shaped body 1 which is able to increase the stiffness of the pulp of the treated portion with respect to the pulp of other portions of the cup-shaped body 1 which are not ultrasonically treated.

It has been found that the ultrasonically stiffened cellulose pulp of the fluid injection portion 7 comprises one or more of the following features:

- the amount of the hydrogen bonds and/or the hornification value of the fibres of the ultrasonically treated cellulose pulp of the fluid injection portion 7 is increased with respect to the amount of the hydrogen bonds and/or the hornification value of the non-ultrasonically treated fibres of the cellulose pulp of the surrounding portions 13A, 13B of the cup shaped body, surrounding said fluid injection portion 7;

- the orientation of the fibres of the fibres of the ultrasonically treated cellulose pulp of the fluid injection portion 7 is different from the orientation of the non-ultrasonically treated fibres of the cellulose pulp of the surrounding portions 13A, 13B of the cup shaped body, surrounding said fluid injection portion 7;

- the water retention value (WRV) of the fibres of the ultrasonically treated cellulose pulp of the fluid injection portion 7 is decreased with respect to the water retention value of the non-ultrasonically treated fibres of the cellulose pulp of the surrounding portions 13A, 13B of the cup shaped body, surrounding said fluid injection portion 7.

It has also been found that the ultrasonically treated cellulose pulp portions have distinguishing features relative to capsules wherein same portions are treated with other stiffening methods, for example with static load compression methods, and when these capsules are made of identical cellulose pulp. The cup-shaped body 1 is preferably revolutionary symmetrical. Preferably, the tubular wall 5 has a frustoconical shape, with a circular cross section and with an increasing diameter towards the annular flange 3.

Preferably, the lateral tubular wall 5, when seen in a longitudinal section, is inclined with respect to a longitudinal axis A of the cup-shaped body 1.

The bottom wall 4 preferably comprises a first inclined wall 4A and a second wall 4B, so as to delimit a shallow concave volume. The first inclined wall 4A preferably has a frustoconical shape, with a circular cross section and with an increasing diameter towards the lateral wall 5. The second wall 4B is preferably flat or convex (from the point of view of the cavity 1A, i.e., protruding intern towards the cavity 1A) as shown in figure 2. As already mentioned above the bottom wall 4 of the cup-shaped body 1, and preferably its inclined wall 4A comprises the fluid injection potion 7 (whose area has been highlighted with a dashed line in the figure 2) suitable for being pierced by the piercing members 12 of the beverage device 10 for the preparation of the beverage. This fluid injection portion 7 has preferably an annular shape and has a width T1 (figure 2) which is comprised between 10% and 100% of the width T2 of the inclined wall 4A. The fluid injection portion 7 is surrounded by portions 13A, 13B of the bottom wall 4 of the cup which are preferably annular shaped parts of the inclined wall 4A. In an alternative embodiment (not shown) the fluid injection portion can be provided in the end wall 4B of the bottom wall 4 of the cup-shaped body, for example in the center of the end wall 4B. In a further alternative embodiment (not shown) the bottom wall 4 of the cup-shaped body comprises a plurality of injection portions separated one from the other.

It is to be noted that the fluid injection portion may have any suitable shape different from the annular one disclosed in the drawings.

In an alternative embodiment not disclosed in the drawing the ultrasonically treated fluid injection portion may extends over the entire inclined wall 4A or even over the entire bottom wall 4. The annular flange 3 comprises a preferably flat wall 3A.

The beverage preparation device 10, parti disclosed in figure 3, comprises the movable enclosing member 9 and a support plate 11 for supporting the cover 2 of the capsule. This support plate 11 tears off the cover 2 and allows the beverage to flow out of the capsule when the liquid injected into the capsule by the liquid piercing members 1 creates a predetermined pressure in the capsule.

As usual for the skilled person, the enclosing member 9 is movable from an initial position (not shown), which allows the introduction of the capsule in the beverage preparation device, and a brewing position (shown in figure 3), wherein the enclosing member 9 and the support plate 11 tightly enclose the capsule. In this position pressurized liquid is injected into the capsule through openings formed by one or more pointed piercing members 12 of the beverage preparation device 10.

These pointed piercing members 12 are designed for piercing the bottom wall 4 of the cup-shaped body 1 at the injection portion 7 of this wall.

The operation of the beverage preparation device 10, as well as the technical features of its various components, are well known to the skilled person and therefore will not be described in detail.

As discussed before, the cup-shaped body 1 is made of cellulose pulp comprising cellulose fibres in a percentage ranging from 80% to 100% by weight.

The term "cellulose fibres" refers to fibres having a wood and/or a wood free origin. The fibres, by way of non-limiting examples, are: hard wood cellulose fibres, soft wood cellulose fibres, wheat fibres, corn fibres, bagasse fibres, bamboo fibres, hemp fibres, cotton fibres, other similar vegetable or plant fibres, or a combination thereof.

The oxygen barrier liner 15 is made of at least one layer and preferably several layers. Preferably the oxygen barrier liner 15 comprises a core layer having oxygen and/or moisture barrier properties, surrounded by a sealing layer for sealing said barrier liner to the cellulose pulp material.

A preferred multilayer barrier liner comprises a core layer having oxygen and/or moisture barrier properties, surrounded by sealing layers for sealing said barrier liner onto the cellulose pulp.

Preferably the barrier liner 15 is provided at all the inner surfaces of the cup-shaped body 1, such as to delimit at least the entire cavity lA for housing the beverage substance.

The oxygen barrier liner 15 is made of a known mono or multilayer polymeric liner, comprising for example a polymer of fossil or non-fossil origin or a BioSource polymer, and is attached to the inner surface of the cellulose pulp cup shaped body of the capsule.

The oxygen barrier liner, by way of non-limiting examples, comprises one or more of following layers:

- an outermost polymeric layer comprising a biodegradable polymer selected within the list of: polybutylene succinate (PBSA / bioPBS), polybutylene adipate terephthalate (PBAT), starch, cellulose derivates, polylactic acid (PLA), polyhydroxyalcanoates (PHA), or a combination thereof,

- a first tie layer comprising a biodegradable modified or functionalized polyolefin,

- a barrier layer comprising a polymer selected within the list of: butenediol vinyl alcohol copolymer (BVOH), polyvinyl alcohol (PVOH) or a combination thereof,

- a second tie layer comprising a biodegradable modified or functionalized polyolefin,

- an innermost polymeric layer comprising a biodegradable polymer selected within the list of: polybutylene succinate (PBSA), polybutylene adipate terephthalate (PBAT), starch, cellulose derivates, polylactic acid (PLA), polyhydroxyalcanoates (PHA) or a combination thereof.

Preferably, the first and outermost polymeric layer has a thickness comprised between 10 and 50 pm, and said layer has an elongation at break comprised between 10% and 800%, a melt flow rate (MFR) comprised between 2 and 4 when measured at 150°C during 10 minutes with a pressure of 2.16 kg, and said layer has a melting point temperature comprised below 80°C.

Preferably, the first tie layer has melting point temperature comprised between 180°C and 230°C and a thickness comprised between 1 and 12 pm.

Preferably, the barrier layer has a melting point temperature comprised between 180°C and 230°C and a thickness comprised between 1 and 15 pm.

Preferably the second tie layer has a melting point temperature comprised between 180°C and 230°C and a thickness comprised between 1 and 10 pm.

Preferably, the innermost polymeric layer has a thickness comprised between 10 and 50 pm, and said innermost layer has an elongation at break comprised between 10% and 1000%, a melt flow rate (MFR) comprised between 4 and 10 when measured at 190°C during 10 minutes with a pressure of 2.16 kg, and said layer has a melting point temperature comprised between 110°C and 180°C.

The cover 2 is made in a known material, preferably it is a polymeric film membrane.

The cover 2 may be flat, i.e., non-formed in a three-dimensional shape.

The cover 2 preferably comprises an oxygen barrier layer. According to the invention, the cup-shaped body 1 of the capsule is preferably obtained by moulding in a mould 16 (figure 3) a dry or wet, preferably wet, cellulose pulp.

Preferably, the cellulose layer 14 of the cup shaped body 1, its oxygen barrier liner 15 and/orthe cover 2 are made of home compostable materials. The capsules according to the invention are normally meant to be recycled in recycling processes that are organized at official recycling facilities according to national regulations (for instance in paper recycling streams, or in general garbage recycling or treatment streams). However, in case the capsule is placed in nature, in a household compostable waste or in a landfill, said capsules are designed with materials that are naturally ready to be degraded by bacteria and in conditions of temperature and humidity that are naturally present in nature. In this way, it is ensured that such capsules will not stay in nature and will naturally disappear within a short period of time (a few weeks in principle) within the conditions defined by home composability standards. More precisely, home composability is now well defined on a national level and mainly based on international standard EN 13432; therefore, they do not require to be further defined in-depth in the present specification. Materials or products compliant with these standards can be recognized by a conformity mark stating their home composability. Some examples of home composability certifications at a national level include, but are not limited to, the following. The certifier TUV AUSTRIA BELGIUM offers such a home composability certification scheme, and DIN CERTCO offers a certification for home composability according to the Australian standard AS 5810. Italy has a national standard for composting at ambient temperature, UNI 11183:2006. In November 2015, the French Standard "NF T 51-800 Plastics - Specifications for plastics suitable for home composting" was introduced. This standard is covered in the DIN CERTCO scheme.

The moulding process is usual for the skilled person and will not be further described in detail. By this moulding process only the cellulose pulp layer 14 of the cup shaped body 1 is made.

After the cellulose pulp layer 14 of the cup shaped body 1 is made, and preferably when the cellulose pulp is dry, the portions of this cellulose pulp layer 15 in which the fluid injection portions 7 are to be obtained, are ultrasonically treated.

For this ultrasonic treatment a usual sonotrode 17 (figure 3) may be used. Preferably, the sonotrode 17 has its active portion 17A, which emits the ultrasonic vibrations, having the same size and shape as that of the fluid injection portion 7. Preferably, the width T3 of the sonotrode active portion 17A is the same as the width T1 (figure 2) of the fluid injection portion 7.

According to the invention, ultrasonic vibrations are applied to a fluid injection portion 7 having an initial thickness comprised between 0,1 mm and 1,5 mm, preferably about 0,8 mm.

Preferably, after the ultrasonic treatment the initial thickness is decreased by 20% - 70%, more preferably by 50%.

According to the invention, ultrasonic vibrations are applied to the fluid injection portion 7 of the cellulose pulp layer 14 with a frequency comprised between 20 kHz and 70 kHz and preferably about 35KHz.

According to the invention, ultrasonic vibrations are applied to the fluid injection portion 7 with an amplitude of the vibration comprised between 13 micrometres and 130 micrometres.

According to the invention, ultrasonic vibrations are applied to the fluid injection portion 7 for a period of time comprised between 0,1 sec and 1 sec, preferably about 0,3 second.

Preferably, during the ultrasonic treatment also a compression load is applied to at least this fluid injection portion 7. For example, the compression load is comprised between 1000 N and 2000 N and preferably is about 1500 N. Preferably, after the ultrasonic treatment of the fluid injection portion 7 of the cup-shaped body 1, the oxygen barrier liner 15 is applied to the internal and/or the external surface of the cup-shaped body 1 in a usual way for the skilled person. Preferably, the oxygen barrier liner 15 is thermoformable polymer and is thermoformed on the cellulose pulp layer 14 of the capsule body 1.

Therefore, the ultrasonic treatment does not affect and/or damage the oxygen barrier liner.

It should be understood that various changes and modifications to the presently preferred embodiment of the capsule described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the scope of the present invention covered by the appended claims. For example, the cup-shaped body and or the fluid injection portion may have a different shape.