WO2025153400A1 - Coffee capsules and lid materials therefore, methods for filling and sealing such coffee capsules and corresponding coffee capsules - Google Patents

Abstract

Container (10,20) for a beverage ingredient, in particular for ground coffee, having a base body (12,21) with a bottom wall (14,24), a circumferential sidewall (13,23) converging to the bottom wall and a flange rim (11,21) extending circumferentially outwardly from an upper edge of the circumferential sidewall (13,23), wherein the container (10,20) is made from cardboard or paper material coated from one or both sides with a sealing composition a.1) made from a water or a water-alcohol mixture, comprising alkyl-trialkoxysilane and at least one of micrometric silica and tetraalkoxysilane; and optionally one or more further components selected from: a.2) a C1-C6 alcohol or a mixture thereof; a.3) a base selected from NaOH and KOH in such an amount as to control the pH in the range between 2 and 5; and a.4) glycerin dyed with a coloring agent approved for food use, as well as lid for such a container.

Description

TITLE

COFFEE CAPSULES AND LID MATERIALS THEREFORE, METHODS FOR FILLING AND SEALING SUCH COFFEE CAPSULES AND CORRESPONDING COFFEE CAPSULES

TECHNICAL FIELD

The present invention relates to food containers, in particular coffee capsules as well as lead materials for sealing such food containers, in particular coffee capsules, methods for filling and sealing such containers and corresponding filled containers.

PRIOR ART

The background of the present invention is the field of capsules which contain beverage or other comestible (e.g. soup) ingredients. By means of an interaction of these ingredients with a liquid, a beverage or other comestibles, such as for example soups, can be produced. The interaction can be for example an extraction, brewing, dissolution, etc. process. Such a capsule is particularly adapted to contain ground coffee in order to produce a coffee beverage by having hot water under pressure enter the capsule and draining a coffee beverage from the capsule.

Systems and methods for obtaining fluid comestibles from substances containing capsules are for example known from EP-A-512470, see Fig. 3 thereof or in particular Fig. 1 of EP 1 654 966. The capsule in that system has a frustoconical-shaped cup which may be filled e.g. with roasted and ground coffee and which is closed by a foil-like tear face cover welded and/or crimped to a flange-like rim which extends laterally from the side-wall of cup. A capsule holder comprises a flow grill with relief surface element members. The capsule holder is accommodated in its support which has a lateral wall and a bore for the passage of extracted coffee beverage. The extraction system further comprises a water injector having a water inlet channel and an annular element with an internal recess of which the shape substantially corresponds to the outer shape of the capsule. On its outer part, the annular member comprises a spring holding a ring for releasing the capsule on completion of extraction. In operation, a capsule is placed in the capsule holder. The water injector perforates the upper face of the cup. The lower tear face of the capsule rests on the radially arranged members of the capsule holder. The water is injected through the channel of the water injector and impinges on the bed of coffee. The pressure in the capsule increases and the tear face increasingly follows the shape of the radial opening relief members. Such radial opening relief members could be replaced by pyramid-shaped reliefs or other shapes of relief. When the constituent material of the tear face reaches its breaking stress, the tear face tears along the relief members. The extracted coffee flows through the orifices of the flow grill and is recovered in a container (not shown) beneath the bore. The principles of this extraction process as far as it can be maintained also in connection with the present invention can be summarized as follows:

An initially sealed capsule is inserted in capsule holder means;

The capsule holder means is then introduced associated to the water injection means of the machine such that an annular element surrounds the sealed capsule.

In a first wall of the capsule at least one opening is generated.

Water entering the capsule through the opening in the first wall is interacting with the ingredients contained in the capsule while traversing the interior of the capsule and is then made to leave the capsule through at least one opening/perforation created in the second wall.

The ingredients in the capsule constitute the "bottleneck" of the flow path of the water and will therefore cause a pressure drop between the upstream and the downstream side of the liquid flow through the capsule, which pressure drop will even increase during the interaction between the liquid and the ingredients for example due to a swelling of the ingredients. Correspondingly it has to be assured that the only water flow is actually taking place through the interior of the capsule and that no water can flow from the water injector into the interstice between the annular enclosing member and the exterior of the capsule and then to the draining bore of the device. Such sealing engagement can be achieved at least to a certain degree by the pinching engagement between the annular member, the flange-like rim of the side wall of the capsule and the capsule holder. In case the sealing engagement is not working properly and water is flowing outside the capsule, no pressure sufficient to cause the tearing of the tear face will be built up inside the capsule or, alternatively, the pressure will be causing no complete tearing of the tear face and therefore a poor extraction of the substance. In such a scenario water will be drained from the beverage production device without having interacted or fully interacted under sufficient pressure conditions, with the ingredients contained in the capsule.

EP-A-1 654 966 proposes a capsule which contains beverage ingredients such as ground coffee, tea or other ingredients and is configured for insertion in a beverage production device in order to have a liquid under pressure have enter the capsule and to interact with the ingredients in the capsule. The capsule comprises a base body and a foil member closing the base body by being attached to a flange-like rim extending from the side wall of the base body of the capsule. The base body of the capsule comprises a resilient sealing member, the sealing member being designed to be in sealing engagement with a bell member of the beverage production device.

The preparation of a beverage by using the centrifugation is also known. The principle mainly consists in providing beverage ingredient in a container of the capsule, feeding liquid in the receptacle and rotating the receptacle at elevated speed to ensure interaction of liquid with powder while creating a gradient of pressure of liquid in the receptacle; such pressure increasing gradually from the centre towards the periphery of the receptacle. As liquid traverses the coffee bed, extraction of the coffee compounds takes place and a liquid extract is obtained that flows out at the periphery of the receptacle.

WO2010/026053 e.g. relates to such a controlled beverage production device using centrifugal forces. The beverage production device for preparing a liquid comestible from a portioned food substance contained in a sealed capsule is comprising a centrifugal unit for receiving the sealed capsule, driving means connected to the centrifugal unit for enabling a rotational motion of the centrifugal unit, liquid supply means being connected to the centrifugal unit, means for measuring the flow rate or the pressure of the supplied liquid and control means for controlling the rotational speed of the driving means dependent on the measured flow rate or the measured pressure of the liquid. The capsule may comprise a barcode provided on an outside face of the capsule and which enables a detection of the type of capsule and/or the nature of ingredients provided within the capsule in order to apply a predefined extraction profile for the beverage to be prepared.

WO-A-2011141532 proposes a capsule for the preparation of a beverage comprising a container and a beverage ingredient contained therein, wherein the container comprises a code adapted for being identified or read by external reading means, wherein the code is arranged on the container to be read while the capsule is rotated around an axis of rotation traversing the capsule.

US-A-2020232164 discloses a coated paperboard container which includes a paperboard substrate and an aqueous barrier coating on the paperboard substrate. The coated paperboard container has a repulpability yield of 75% accepts or greater, a sidewall seam bond strength of 30 pounds per inch or greater, and a wet rigidity loss of 50% or less.

US-A-2017174417 discloses a capsule for the preparation of a beverage in a beverage preparation device. The capsule has a flange which is partially made of paper and partially made of polymer. The polymer is essentially arranged on the flange to cover at least partially the paper part and so to improve the inside tightness of the capsule, in particular, to prevent air enters inside the capsule via folds and creases.

WO-A-2023041505 in a first aspect discloses a capsule for containing beverage ingredients configured to be inserted in a beverage production device. The capsule comprises a body defining a cavity to contain beverage ingredients. The body comprises an upper portion, a lower portion, a sidewall extending from the upper portion to the lower portion, wherein the lower portion comprises an annular flange outwardly extending from the sidewall. The annular flange comprises an upper side facing towards the upper portion of the body. The capsule further comprises a sealing member arranged on the upper side of the annular flange. The sealing member comprises an inner layer facing the upper side of the annular flange comprising an adhesive and an outer layer having a mass-colored cellulose material. In a further aspect, a method for manufacturing such capsule is provided.

WO-A-2022171893 discloses a process for the treatment of paper or cardboard surface that makes them impermeable to water, oil, and atmospheric gases, in particular oxygen. The invention also relates to the impermeable paper or cardboard thus obtained, which are particularly suitable for producing food product packaging or tableware.

SUMMARY OF THE INVENTION

A problem with the existing systems is that they are relying on aluminum or plastics as the base material for the actual container portion as well as for the lid portion, with the associated cost, recyclability and production expenses and problems. While aluminum- based approaches provide for good sealing properties, they are expensive and can be recycled but only with a lot of effort and are ecologically difficult in providing the raw material. Plastics based materials are not equally impermeable to air and coffee flavor or are so only if very specific plastic materials are used which are costly, and also they normally cannot be recycled; furthermore the raw material is ecologically difficult.

There are approaches which rely on recyclable materials, including paper, however the corresponding approaches so far have proven to be insufficiently air impermeable, or insufficiently humidity and/or steam and/or water impermeable, or insufficiently recyclable if means to counter the impermeability problems are taken. Furthermore, these materials are difficult to transform into corresponding shapes of the containers and cannot simply be structured by for example printing, laser marking or coating.

It is thus an object of the present invention to provide for a new material which is suitable and adapted to act as a material for a food container, and in particular takes the form of a food container, i.e. of an actual container with a cavity to contain the food or a lid for such a container. In particular it relates to the provision of coffee capsule containers and correspondingly materials, as well as combinations thereof, in empty or filled form, i.e. it also relates to coffee filled coffee capsule containers.

The term "container" refers to any flexible, rigid or semi-rigid container containing beverage ingredient. Other synonymous to a capsule are: "pod", "pad", "cartridge". The container can be single use. The container can also be filled with ingredient by the user to form the capsule just before use.

The term ingredient means any suitable beverage substance such as ground coffee, soluble coffee, leaf tea, soluble tea, herbal tea, dairy powder, baby food, culinary powder and combination thereof.

According to a first aspect of the present invention, it relates to a container for a beverage ingredient, in particular for ground coffee, having a base body with a bottom wall, a circumferential sidewall converging to the bottom wall and a flange rim extending circumferentially outwardly from an upper edge of the circumferential sidewall.

The flange rim extending circumferentially outwardly from an upper edge of the circumferential sidewall can be flat. According to a further preferred embodiment and with the aim of increasing the sealing properties at the rim, at the terminal edge of the horizontal rim there can be provided a kink in the rim with a vertical terminal portion , which preferably points in the direction away from the opening of the dome shaped container. A further improvement can be achieved, if there is not only such a kink, but if the horizontal rim forms a circumferential bulge protruding in the direction of the opening of the dome shaped container, the vertical terminal portion forming the terminal end of that bulge.

The height of the bulge above the horizontal part of the horizontal rim is typically in the range of 0.5-3 mm, preferably in the range of 0.75-2 mm, and the length of the vertical terminal portion in a vertical direction is in the range of 0.5-4 mm, preferably in the range of 1-3 mm. In other words, preferably the edge of the free circumferential end of the vertical terminal portion of the rim is below the lower surface of the horizontal portion of the vertical rim, i.e. the edge of the vertical terminal portion is 0.5-3 mm, preferably in the range of 0.75- 2 mm below the lower surface of the horizontal portion of the vertical rim.

The container is made from (consists of) cardboard or paper material coated from one or both sides with a sealing composition (in particular an alkyl-modified silica sealing composition) made of or produced starting from an aqueous and/or hydroalcoholic liquid composition comprising a.1) alkyl-trialkoxysilane and at least one of micrometric silica and tetraalkoxysilane. Preferably the starting composition comprises alkyl-trialkoxysilane as well as micrometric silica and tetraalkoxysilane.

Micrometric silica is amorphous silica in the form of powders; the powders are made of primary particles of nano-sized silica (i.e., smaller than 1 micrometer, pm, typically between about 5 and 100 nm) aggregated to form micrometer-sized secondary particles, with size between about 1-100 pm. This material may be produced by combustion of vapors of silicon tetrachloride (SiCU) with oxygen in special chambers; in this case, the material is also known in the art as "pyrogenic silica" or "fumed silica". Alternatively, the silica powders may be obtained by precipitation from diluted aqueous solutions alkali metal silicate (e.g., a waterglass solution, namely a solution of sodium silicates of general formula Na2O.xSiO2, wherein is x = 2-4) with a diluted acid (e.g., sulfuric acid or hydrochloric acid); in this case the obtained amorphous silica is called in the art "precipitated silica". Given the intended use of the products of the present invention (contact with food), the micrometric silica should have a purity of not less than 99.5%; this characteristic may be checked by chemical analysis, and is intrinsically guaranteed by fumed silica obtained by combustion as described above. Micrometric silica is widely available commercially and is sold, for example, by the company Evonik Resource Efficiency GmbH, Essen (Germany) under the name AEROSIL® (for example, the product AEROSIL® OX 50), or by the company Cabot Corporation, Boston, Massachusetts (USA) under the name CabOSil®. The concentration of micrometric silica in the water-silica suspension may vary between 10% and 70%, preferably between 10 and 65%, and even more preferably between 20 and 40% by weight. To obtain a homogeneous suspension, micrometric silica can be added to water under mechanical stirring, for example with an UltraTurrax® series mixer (manufactured and sold by the company IKA®-Werke GmbH & Co. KG, Staufen, Germany) or similar devices.

Without being bound to any theoretical explanation, after application on the surfaces(s) of the cardboard or paper material, the alkoxy groups of the alkyl-trialkoxysilane and of the possibly present tetraalkoxysilane undergo hydrolysis (in particular in the heating step), namely, are replaced by -OH groups linked to the silicon atom; thereafter, the -OH groups linked to different silicon atoms react in a condensation reaction, namely, eliminating a water molecule with formation of an oxygen "bridge” Si-O-Si; this mechanism, repeated on most or even all originally present alkoxy groups, ultimately gives rise to a three-dimensional network of vitreous silica, modified by the presence of a certain amount of Si-alkyl groups (these groups are not hydrolyzed in the first part of the reaction) corresponding to the molar ratio of alkyl-trialkoxysilane to silica/ tetraalkoxysilane in the starting liquid composition. The final material resulting from this process will be referred to in the rest of the description and in the claims as “alkyl-modified silica”.

The sealing coating as present on the final dry container on one or both sides correspondingly is an alkyl-modified silica coating, in particular one based on and/or preferably prepared starting from an aqueous and/or hydroalcoholic liquid composition comprising or consisting of a.1) water or a water-alcohol mixture, comprising alkyl- trialkoxysilane and at least one of micrometric silica and tetraalkoxysilane. Preferably the starting composition comprises or consists of a.1) water or a water-alcohol mixture, comprising alkyl-trialkoxysilane as well as micrometric silica and tetraalkoxysilane.

The starting composition optionally comprises or consists of one or more further components selected from: a.2) a C1-C6 alcohol or a mixture thereof; a.3) a base selected from NaOH and KOH in such an amount as to control the pH in the range between 2 and 5, preferably in the range of 2.3 and 4.5; and a.4) glycerin dyed with a coloring agent approved for food use.

At the end of the production process, after the thermal treatment that is the last step as described below, the sealing coating present on the container consists of the alkyl-modified silica described above possibly including Na or K atoms in case component a.3) was used, and/or glycerin and/or a coloring agent in case component a.4) was used. The water or alcohols present in the starting liquid composition a.1), the alcohol produced/released by hydrolysis of the alkyl-trialkoxysilane and of the possibly present tetraalkoxysilane, and water and/or alcohol possibly added as component a.2), are eliminated by evaporation during said final thermal treatment.

Preferably the starting composition consists of a.1) water or a water-alcohol mixture, comprising alkyl-trialkoxysilane and at least one of micrometric silica and tetraalkoxysilane and optionally one or several of the above mentioned components a.2)-a.4). So the sum of a.1)- a.4) makes 100% of the composition. The sealing composition is preferably made produced starting from an aqueous or hydroalcoholic liquid composition comprising or consisting of: a.1) between 5% and 20% by weight of micrometric silica,

15% and 40% by weight of a hydrolyzed tetraalkoxysilane, and between 25% and 40% by weight of a hydrolyzed alkyl-trialkoxysilane.

Optionally the starting liquid composition the sealing composition is made from or comprises one or more further components selected from: a.2) water and/or between 10% and 50% by weight of a C1-C6 alcohol or a mixture thereof; a.3) a base selected from NaOH and KOH in such an amount as to control the pH in the range between 2 and 5, preferably in the range of 2.3 and 4.5; and a.4) between 2% and 15% by weight of glycerin dyed with a coloring agent approved for food use.

Again, preferably the sealing composition is produced from a starting composition consisting of a.1) a solvent selected from water or a hydroalcoholic mixture, alkyl- trialkoxysilane, micrometric silica and tetraalkoxysilane in the above amounts and optionally the above-mentioned components a.2)-a.4) in the above amounts. Since the solvent evaporates during application of the sealing coating, the coating as present on the final dry container typically consists of the alkyl-modified silica described above possibly including one or more of Na or K atoms, glycerin and a coloring agent, in the amounts indicated for components a.3) and a.4), as described above for the sealing coating. The weight percent in the final sealing coating of Na or K atoms, glycerin and coloring agent derive from the amounts reported above for components a.3) and a.4), rescaled for the loss of water and alcohol due to evaporation in the thermal treatment that is the last step of the production process.

According to a preferred embodiment, the thickness of the bottom wall and the circumferential sidewall is in the range of 120-750 pm, preferably in the range of 200-600, most preferably in the range of 300-500 pm.

According to a preferred embodiment, the thickness of the flange rim is in the range of 120- 750 pm, preferably in the range of 150-500 pm, most preferably in the range of 200-250 pm.

The sealing composition is preferably applied to a coating base material with a coat weight (dry weight) in the range of 0.5-5 g/m2, preferably in the range of 1-4 g/m2, most preferably in the range of 1.5-2.5 g/m2.

The container is normally axially symmetric, and the flange rim, and preferably also at least part of the circumferential sidewall and optionally also but only part of the bottom wall are based on a blank or precut material which initially contained radial incisions, which after coating of the blank material with the sealing composition and wet forming of the container in at least one forming step have been fusioned to form a contiguous flange rim and, if incisions penetrated into the circumferential sidewall, or even into part of the bottom wall, a contiguous circumferential sidewall and a contiguous bottom wall.

The container can be produced using a method as disclosed in WO 2022/171893, which is incorporated by reference as concerns the manufacturing method.

This means that the method comprises the following steps: providing a flat piece of starting material, from roll or sheet wise; coating that starting material at least from one side with a sealing liquid composition; at least partly drying the coated starting material from one or both sides; subjecting the coated starting material to at least one forming step followed by at least one cutting step, wherein the cutting step may be combined with a forming step; wherein the sealing liquid composition is a treatment solution comprising: a.1) water or a water-alcohol mixture, comprising alkyl-trialkoxysilane and at least one of micrometric silica and tetraalkoxysilane, wherein preferably the sealing composition comprises alkyl-trialkoxysilane as well as micrometric silica and tetraalkoxysilane.

Further preferably the composition is: between 35% and 100% by weight of an aqueous solution containing: a.1) micrometric silica, preferably between 5% and 20% by weight of micrometric silica, tetraalkoxysilane, preferably between 15% and 40% by weight of a hydrolyzed tetraalkoxysilane, and alkyl-trialkoxysilane, preferably between 25% and 40% by weight of a hydrolyzed alkyltrialkoxysilane; and optionally one or more further components selected from: a.2) between 10% and 50% by weight of a C1-C6 alcohol or a mixture thereof; a.3) a base selected from NaOH and KOH in such an amount as to control the pH in the range between 2 and 5, preferably in the range of 2.3 and 4.5; and a.4) between 2% and 15% by weight of glycerin dyed with a coloring agent approved for food use; and wherein said drying involves subjecting the coated starting material to a thermal treatment at a temperature between 100 and 250 °C while forming the container, typically at 120 °C for about 1-5 s. Forming may take place in one or several forming stations.

The bottom wall may take the form of a dome shaped hemisphere, and wherein preferably the circumferential sidewall comprises at least one essentially linear portion with an opening angle in the range of 1-15°, preferably in the range of 2-8°,

Preferably the height of the circumferential sidewall in this case is in the range of 5-15 mm, preferably in the range of 7-12 mm.

Preferably the radius of the hemisphere in this case is in the range of 18-27 mm, preferably in the range of 20-25 mm.

The bottom wall may also take the form of a conical bottom part, with a converging portion and a bottom wall.

In this case the height of the circumferential sidewall is in the range of 15-28 mm, preferably in the range of 20-27 mm.

According to another aspect of the present invention, it relates to a lid material for a container of the above type for a beverage ingredient, in particular for a container for ground coffee, having a base body with a bottom wall, a circumferential sidewall converging to the bottom wall and a flange rim extending circumferentially outwardly from an upper edge of the circumferential sidewall, said lid material being for attaching the lid to said rim for closing the interior of the container, wherein the lid material is made from cardboard or paper material coated from one or both sides with a sealing composition made or and/or produced starting from an aqueous or hydroalcoholic liquid composition comprising or consisting of alkyl-trialkoxysilane and at least one of micrometric silica and tetraalkoxysilane. Preferably the sealing composition is produced from a liquid composition that comprises or consists of a water or a water-alcohol mixture, comprising alkyl-trialkoxysilane as well as micrometric silica and tetraalkoxysilane.

The sealing coating as present on the final dry lid material on one or both sides correspondingly preferably comprises or consists of an alkyl-modified silica as described above. Preferably the sealing composition is produced starting from a liquid composition which comprises or consists of a water or a water-alcohol mixture, comprising alkyltrialkoxysilane as well as micrometric silica and tetraalkoxysilane.

The starting liquid composition for the sealing coating optionally comprises one or more further components selected from: a.2) water and/or a C1-C6 alcohol or a mixture thereof; a.3) a base selected from NaOH and KOH in such an amount as to control the pH in the range between 2 and 5, preferably in the range of 2.3 and 4.5; and a.4) glycerin dyed with a coloring agent approved for food use and wherein on only one side it is coated with a heat-sealing composition.

Preferably the starting liquid composition from which the sealing composition is produced consists of a.1) water or a water-alcohol mixture, comprising alkyl-trialkoxysilane and at least one of micrometric silica and tetraalkoxysilane and optionally one or several of the above-mentioned components a.2)-a.4).

Since the solvent evaporates during application of the sealing coating, the coating as present on the final dry lid material typically comprises or consists of an alkyl-modified silica as described above.

The sealing composition is preferably made starting from a liquid composition comprising or consisting of: a.1) water or a water-alcohol mixture, comprising between 5% and 20% by weight of micrometric silica,

15% and 40% by weight of a hydrolyzed tetraalkoxysilane, and between 25% and 40% by weight of a hydrolyzed alkyl-trialkoxysilane; and optionally one or more further components selected from: a.2) water and/or between 10% and 50% by weight of a C1-C6 alcohol or a mixture thereof; a.3) a base selected from NaOH and KOH in such an amount as to control the pH in the range between 2 and 5, preferably in the range of 2.3 and 4.5; and a.4) between 2% and 15% by weight of glycerin dyed with a coloring agent approved for food use.

Again, preferably the starting liquid sealing composition consists of a.1) water or a water- alcohol mixture, comprising alkyl-trialkoxysilane, micrometric silica and tetraalkoxysilane in the above amounts and optionally the above-mentioned components a.2)-a.4) in the above amounts. Since the solvent evaporates during application of the sealing coating, the coating as present on the final dry lid material typically comprises or consists of an alkyl-modified silica as described above. The thickness of the lid material including the heat-sealing composition coating is normally in the range of 120-500 pm, preferably in the range of 200-400, most preferably in the range of 250-300 pm.

The lid material, on the side opposite to the heat-sealing coating, can be provided with a filter layer, in particular in case of container with a bottom wall which takes the form of a conical bottom part, with a converging portion and a bottom wall.

The lid material can be produced using a method as disclosed in WO 2022/171893, which is incorporated by reference as concerns the manufacturing method. This means that the method comprises the following steps: providing a flat piece of starting material, from roll or sheet wise; coating that starting material at least from one side with a sealing composition; drying the coated starting material; coating that coated starting material from only one side with a heat-sealing composition; wherein the sealing composition is a treatment solution comprising: a.1) water or a water-alcohol mixture, comprising alkyl-trialkoxysilane and at least one of micrometric silica and tetraalkoxysilane, wherein preferably the sealing composition comprises alkyl-trialkoxysilane as well as micrometric silica and tetraalkoxysilane.

Further preferably the composition is: between 35% and 100% by weight of an aqueous solution containing: a.1) water or a water-alcohol mixture, comprising micrometric silica, preferably between 5% and 20% by weight of micrometric silica, tetraalkoxysilane, preferably between 15% and 40% by weight of a hydrolyzed tetraalkoxysilane, and alkyl-trialkoxysilane, preferably between 25% and 40% by weight of a hydrolyzed alkyl- trialkoxysilane; and optionally one or more further components selected from: a.2) between 10% and 50% by weight of a C1-C6 alcohol or a mixture thereof; a.3) a base selected from NaOH and KOH in such an amount as to control the pH in the range between 2 and 5, preferably in the range of 2.3 and 4.5; and a.4) between 2% and 15% by weight of glycerin dyed with a coloring agent approved for food use; and wherein said drying involves subjecting the coated starting material to a thermal treatment at a temperature between 100 and 250 °C, typically at 120°C for about 1-5 s. Furthermore, the present invention relates to a method for producing a sealed coffee capsule containing ground coffee for single portion extraction, wherein a container as given above is provided in a first step, in a second step the interior of said container is filled with ground coffee, and in a third step lid material as given above is attached to the rim of the coffee capsule with its heat-sealing composition coated side facing the interior of the coffee capsule by applying heat and/or pressure from the backside of said rim and/or from the side facing away from the heat-sealing composition coated side of the lid material at least in the rim area.

Furthermore, the present invention relates sealed coffee capsule containing ground coffee for single portion extraction, with such a container and such a lid material, preferably obtained in such a process.

Further embodiments of the invention are laid down in the dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention are described in the following with reference to the drawings, which are for the purpose of illustrating the present preferred embodiments of the invention and not for the purpose of limiting the same. In the drawings,

Fig. 1 shows a dome shaped container according to a first embodiment, wherein in a) a top view is shown, in b) a cut along A-A according to a), in c) the detail according to B in b), in d) a perspective view from the bottom side, in e) a perspective view from the opening side, and in f) an alternate embodiment of a horizontal rim structure;

Fig. 2 shows a dome shaped container according to a second embodiment, wherein in a) a top view is shown, in b) a cut along A-A through a stack according to a), in c) the detail according to upper D in b), in d) a perspective view from the bottom side, in e) a perspective view from the opening side, and in f) the full detail according to upper D in b);

Fig. 3 shows a conical shaped container according to another embodiment, wherein in a) a top view is shown, in b) a cut along A-A according to a), in c) the detail according to B in b), and in d) the detail according to C in b);

Fig. 4 shows cuts through the different materials, wherein in a) a cut through a lid material for a conical shaped container is shown, in b) a cut through a lid material for a dome shaped container, and in c) a cut through the material for the body portion of the container;

Fig. 5 shows different possibilities for the blank being the basis for the forming process of the actual container, wherein different possible shapes are shown in a)-d);

Fig. 6 shows a schematic representation of a possible production process for the container portion. DESCRIPTION OF PREFERRED EMBODIMENTS

Fig. 1 shows a first embodiment of a container in the form of a coffee capsule, which in this case is a dome shaped container 10, which has a horizontal rim 11 , extending outwardly and radially in one plane oriented perpendicular to the axis 16 of the container.

It is one piece with the body portion 12 which encloses the fill volume 30, and which is dome shaped.

The capsule of this type, like the one illustrated in Fig. 2, is suitable and adapted to be used in a system as described in WO2010/026053, so a system with centrifugal extraction.

The body portion 12 comprises a straight portion 13 which has an opening angle f of about 7°, this straight portion 13 is adjacent to the rim 11 on the upper side and adjacent to a rounded dome portion 14 forming the bottom of the capsule.

The edge portion 15 between the straight portion 13 and the horizontal rim 11 typically has a radius b of about 0.5 mm. The outer diameter of the rim 11 is typically around 58 mm, the inner diameter g is typically in the range of 48 mm. The radius d of the rounded dome portion 14 is typically in the range of 23-24 mm.

The lid in this case is attached to the top side 18 of the rim by putting the lid with the heatsealing lacquer, after having filled the volume 30 with ground coffee, facing that top side 18 and applying heat and/or pressure to seal the lid to the rim 11 circumferentially.

On the backside 17 of the rim 11 there can be provided a line pattern or the like, for example a barcode, for identifying the capsule and/or controlling the coffee machine.

In order to be suitable and adapted and to have an appropriate stiffness, thickness and mechanical strength for storage, extraction and removal of the capsule subsequent to extraction from the machine, the thickness a of the sealing layer coated material in the rim portion is typically 300-500 pm. About the same thickness applies to the portion 12 of the capsule.

In order to properly operate in the machine, it is important that the thickness of the rim 11 together with the thickness of the lid is properly adapted, preferably this is done by providing the combined thickness of rim and lid in the range of 200-500 pm. The required thickness can be achieved by pressing the rim selectively in a separate step (e.g during application of the lid) and/or by applying an appropriate high amount of sealing coating, typically in the range of 2-5 g/m2. Increasing the amount of coating can contribute to increased mechanical stiffness of the rim.

Using the paper-based material with a sealing coating as described above leads to a capsule which has a very low oxygen permeability, a low permeability to other small (flavor) molecules of the coffee, and at the same time a low water and/or steam and/or humidity permeability. However, since the base material is only paper and the above-mentioned coating, it is recyclable and can be composted. Care has to be taken that for being compostable also the heat-sealing lacquer is of a compostable type.

As discussed above and illustrated in Fig. 1 so far, the horizontal rim 11 can be straight. In order to further improve the sealing properties in the rim portion during extraction, it is possible to structure the horizontal rim 11 in a way as illustrated in Fig. 1f). The horizontal rim 11 in this case first, adjacent to the straight portion 13 of the wall and after the curve or edge portion 15, comprises a straight horizontal portion 11". This is bending upwards and then horizontal forming a bulge 11", protruding above the upper surface of the horizontal portion 11". The bulge 11" terminates with a vertically extending portion 1 T", the tip of which extends below the lower surface of the horizontal portion 1 T.

Such a structure can be produced in a manufacturing process which is suitable and adapted for the materials and processes described here and significantly increases the sealing properties during the extraction process. This concept can be applied to any of the containers illustrated in the figures of this application.

A stackable version of this type of capsule is illustrated in Fig. 2.

In this case the straight portion 13 comprises an upper straight portion 13', which is directly adjacent to the rim 11 , and which has a height of a about 5 mm. This is followed in a transition 19 with an outer side radius i of about 0.8 mm and an inner side radius k also of about 0.8 mm by a second straight portion 13"with a slightly larger converging angle. The converging angle of the first straight portion 13' is about 2°, while the converging angle of the second straight portion 13" is about 7°. As illustrated in b) and d) this provides for the possibility of stacking an array of capsules and simplifies handling in the storing and filling process.

Fig. 3 shows another embodiment of a container in the form of a coffee capsule, which in this case is a conical container 20, which has a horizontal rim 21 , extending outwardly and radially in one plane oriented perpendicular to the axis 26 of the container. It is one piece with the body portion 22 which encloses the fill volume 30, and which is conical shaped. The capsule of this type is suitable and adapted to the system as described example in EP 1 654 966.

The horizontal rim 21 has an upper side 28 and backside 27, in this case on the backside that can be provided a sealing element for providing sealing in the brewing machine. A corresponding sealing can be provided by an elastic material which is compostable.

The rim 21 by way of the edge portion 25 transitions to the straight portion 23, which in this case also has an upper portion 23' and a lower portion 23", between which there is a transition portion 29 with an inner radius k which is typically in the range of 0.8 mm. The outer diameter h of the rim 21 is in the range of 40 mm, the inner diameter g is typically in the range of 30 mm. The opening angle n of the straight portion 23' is typically in the range of 7.5° and the angle p of the straight portion 23" is typically in the range of 86°. The bottom of the capsule is formed by a conical bottom portion 24 which has an actual bottom 24' as well as a cone portion 24". The cone portion has an angle o typically in the range of 30°. The diameter m of this flat or slightly concave bottom is typically in the range of 11 mm.

In order to be suitable and adapted and to have an appropriate stiffness, thickness and mechanical strength for storage, extraction and removal of the capsule subsequent to extraction from the machine, the thickness a in the rim portion here is typically 300-500 pm. About the same thickness I applies to the portion 22 of the capsule part 22. In order to properly operate in the machine, it is important that the thickness of the rim 21 together with the thickness of the lid and if there is provided a sealing, is properly adapted, preferably this is done by providing the combined thickness of rim and lid in the range of 200-700 pm. The required thickness can be achieved by applying an appropriate high amount of sealing coating, typically in the range of 2-5 g/m2. Increasing the amount of coating can contribute to increased mechanical stiffness of the rim.

A corresponding lid material is illustrated in Fig. 4, specifically in a) a cut through a lid material is shown, showing the actual lid material as a whole 40, the heat-sealing lacquer layer 45 which is going to face the upper side of the rim (18/28), followed by the sealing coating layer 44, then followed by the paper layer 43 and the sealing coating layer 42 on the opposite side of the paper layer 43.

There can be provided an additional filter layer in particular for the embodiment as illustrated in Fig. 3.

For the embodiment as illustrated in Figs. 1 and 2 there is no need of having such a filter layer on the side 48 opposite to the capsule facing side 49.

In Fig. 4c a cut through the actual material of the body portion is given, in this case there is only the sealing coating layers 42 and 44, and the central paper layer 43.

It is noted that the illustrations in this figure are not to scale, so the thicknesses are schematically illustrated. Furthermore, the sealing coating layers may fully penetrate the actual paper layer at least partly, so there might be no central paper layer portion which is completely free from sealing material.

If a wet forming process is used after application of the sealing coating, it is possible to use blank shapes as illustrated in Fig. 5 as starting material. The blank pieces 50 are provided with radially extending incisions, and the examples given in Fig. 5 there are four such incisions equally distributed over the circumference, and there is a central portion 53 keeping the whole blank piece 50 together, i.e. the protruding flaps 52. These blank pieces can be individually introduced into the coating and subsequent forming process assisted by heating, and in that forming process due to the generation of the three-dimensional shape and the overlap of the flaps 52 which are wetted by the coating, the contiguous walls of the body portion 12/22 and of the lid 11/21 are formed. Also, it is possible to have concave portions 54 on the outline of the blank.

As pointed out above, capsules can be produced using the process as disclosed in WO 2022/171893, which is schematically illustrated in Fig. 6.

The starting paper or cardboard material can be provided from a roll 2, and can be introduced into the process as a web 3. It is possible to cut individual blanks as illustrated in figure 5 or to at least generate cutouts according to the incisions 51 before entering the actual coating station 1 , in which the sealing coating is applied to both sides of the paper. This is followed, still in the wet state, by introducing the material into a first forming station 4, in which typically the body portion 12/22 is formed under heat treatment. This is then followed by one or more additional forming steps, if need be also under heat treatment, in this case there is a further forming step 5 providing for an appropriate shape and orientation of the rim. This is then followed by a cutting station 6.

For the production of the lid material, the stations 4 and 5 can be replaced by one single heat treatment and/or forming station. Also, the cutting station 6 does not necessarily have to be immediately after the heat treatment, cutting may also take place in a separate station or shortly before applying the lid to a filled container.

LIST OF REFERENCE SIGNS

1 Coating station

2 Paper roll

3 Paper web

4 First forming station

5 second (flange) forming station

6 Final cutting station

7 Blank cutting station

10 dome-shaped container

11 horizontal rim of 10

1 T flat horizontal portion of 11

11" bulge portion of 11

11 vertical terminal portion of 11

12 body portion of 10

13 straight portion of 12 13' upper portion of 13

13" lower portion of 12

14 rounded dome portion of 12

15 edge portion between 11 and 13

16 axis of 10

17 backside of 11

18 topside of 11

19 transition portion between 13' and 13'

20 conical container

21 horizontal rim of 20

22 body portion of 20

23 straight portion of 22

23' upper portion of 23

23" lower portion of 22

24 conical bottom portion of 20

24' bottom of 24

24" cone portion of 24

25 edge portion between 21 and 23

26 axis of 20

27 backside of 21

28 topside of 21

29 transition portion between 23 and 24

30 fill volume of 10/20

40 lid material cut for conical container

41 filter with material layer

42 coating layer

43 paper layer

44 coating layer

45 heat-sealing lacquer layer

46 lid material cut for dome shaped container

47 body portion material cut for both types of container

48 outer facing side of 40/46

49 fill volume side of 40/46 50 blank piece before forming

51 incision

52 protruding flap

53 connecting portion between 52

54 concave portion of outer edge of 52 a rim thickness of 11/21 b outer side radius of 15 c height of 13 d curvature radius 14 e full height of 10/20 f opening angle of 13 g inner radius of 13/23 at the opening h outer radius of rim 11/21 i outer side radius of 19 k inner side radius of 19/29

I thickness of 12/22 m diameter of 24' n opening angle of 23' o cone angle of 24 p angle of 23"

Claims

1. Container (10,20) for a beverage ingredient, in particular for ground coffee, having a base body (12,21) with a bottom wall (14,24), a circumferential sidewall (13,23) converging to the bottom wall and a flange rim (11 ,21) extending circumferentially outwardly from an upper edge of the circumferential sidewall (13,23), wherein the container (10,20) is made from cardboard or paper material coated from one or both sides with a sealing composition produced starting from a liquid composition comprising or consisting of a.1) water or a water-alcohol mixture, comprising alkyl-trialkoxysilane and at least one of micrometric silica and tetraalkoxysilane; and optionally one or more further components selected from: a.2) a C1-C6 alcohol or a mixture thereof; a.3) a base selected from NaOH and KOH in such an amount as to control the pH in the range between 2 and 5; and a.4) glycerin dyed with a coloring agent approved for food use.

2. Container (10,20) according to claim 1 , wherein the sealing composition is produced starting from a liquid composition comprising or consisting of a.1) water or a water-alcohol mixture, comprising alkyl-trialkoxysilane, micrometric silica and tetraalkoxysilane; and optionally one or more of said further components a.2)-a.4).

3. Container (10,20) according to claim 2, wherein the sealing composition is produced starting from a liquid composition comprising or consisting of a.1) water or a water-alcohol mixture, comprising between 5% and 20% by weight of micrometric silica,

15% and 40% by weight of a hydrolyzed tetraalkoxysilane, and between 25% and 40% by weight of a hydrolyzed alkyl-trialkoxysilane; and optionally one or more further components selected from: a.2) between 10% and 50% by weight of a C1-C6 alcohol or a mixture thereof; a.3) a base selected from NaOH and KOH in such an amount as to control the pH in the range between 2 and 5, preferably in the range of 2.3 and 4.5; and a.4) between 2% and 15% by weight of glycerin dyed with a coloring agent approved for food use the remainder to 100% being water or a water-alcohol mixture.

4. Container (10,20) according to any of the preceding claims, wherein the thickness of the bottom wall and the circumferential sidewall is in the range of 120-750 pm, preferably in the range of 200-600, most preferably in the range of 300-500 pm, and/or wherein the thickness of the flange rim is in the range of 120-750 pm, preferably in the range of 150-500 pm, most preferably in the range of 200-250 pm, and/or wherein the flange rim (11) extending circumferentially outwardly from an upper edge of the circumferential sidewall is straight, and/or wherein at a circumferential terminal edge of the flange rim (11) there is kink in the flange rim (11) with a circumferential vertical terminal portion (1 T"), which preferably points in the direction away from the opening of the preferably dome shaped container, and/or wherein preferably the horizontal rim (11), after a circumferential horizontal straight portion (11'), forms a circumferential bulge (11") protruding in the direction of the opening of the container, said circumferential vertical terminal portion (1 T") forming the terminal end of that circumferential bulge (11").

5. Container (10,20) according to any of the preceding claims, wherein the sealing composition is applied to a coaching base material with a coat weight in the range of 0.5-5 g/m2, preferably in the range of 1-4 g/m2, most preferably in the range of 1.5-2.5 g/m2.

6. Container (10,20) according to any of the preceding claims, wherein it is axially symmetric, and wherein the flange rim, and preferably also at least part of the circumferential sidewall and optionally also but only part of the bottom wall are based on a blank material (50) which initially contained radial incisions (51), which after coating of the blank material with the sealing composition and wet forming of the container (10,20) in at least one forming step (4,5) have been fusioned to form a contiguous flange rim and, if incisions penetrated into the circumferential sidewall, or even into part of the bottom wall, a contiguous circumferential sidewall and a contiguous bottom wall.

7. Container (10,20) according to any of the preceding claims, wherein the bottom wall takes the form of a dome shaped hemisphere (12), and wherein preferably the circumferential sidewall (13) comprises at least one essentially linear portion with an opening angle (f) in the range of 1-15°, preferably in the range of 2-8°, wherein further preferably the height of the circumferential sidewall (13) is in the range of 5-15 mm, preferably in the range of 7-12 mm, and/or wherein further preferably the radius of the hemisphere is in the range of 18-27 mm, preferably in the range of 20-25 mm.

8. Container (10,20) according to any of the preceding claims, wherein the bottom wall takes the form of a conical bottom part (24), with a converging portion (24") and a bottom wall (24'), wherein preferably the height of the circumferential sidewall (23) is in the range of 15-28 mm, preferably in the range of 20-27 mm.

9. Lid material (40, 46) for a container with a beverage ingredient, in particular for a container for ground coffee, having a base body (12,21) with a bottom wall (14,24), a circumferential sidewall (13,23) converging to the bottom wall and a flange rim (11 ,21) extending circumferentially outwardly from an upper edge of the circumferential sidewall (13,23), said lid material being for attaching the lid to said rim for closing the interior of the container wherein the lid material is made from cardboard or paper material coated from one or both sides with a sealing composition is produced starting from a liquid composition comprising or consisting of a.1) water or a water-alcohol mixture, comprising alkyl-trialkoxysilane and at least one of micrometric silica and tetraalkoxysilane; and optionally one or more further components selected from: a.2) a C1-C6 alcohol or a mixture thereof; a.3) a base selected from NaOH and KOH in such an amount as to control the pH in the range between 2 and 5, preferably in the range of 2.3 and 4.5; and a.4) glycerin dyed with a coloring agent approved for food use and wherein on only one side it is coated with a heat-sealing composition.

10. Lid material (40, 46) according to claim 9, wherein the sealing composition is produced starting from a liquid composition comprising a.1) water or a water-alcohol mixture, comprising alkyl-trialkoxysilane, micrometric silica and tetraalkoxysilane and optionally one or more of said further components a.2)-a.4).

11. Lid material (40, 46) according to claim 10, wherein the sealing composition is produced starting from a liquid composition comprising or consisting of a.1) water or a water-alcohol mixture, comprising between 5% and 20% by weight of micrometric silica, between 15% and 40% by weight of a hydrolyzed tetraalkoxysilane, and between 25% and 40% by weight of a hydrolyzed alkyl-trialkoxysilane; and optionally one or more further components selected from: a.2) between 10% and 50% by weight of a C1-C6 alcohol or a mixture thereof; a.3) a base selected from NaOH and KOH in such an amount as to control the pH in the range between 2 and 5, preferably in the range of 2.3 and 4.5; and a.4) between 2% and 15% by weight of glycerin dyed with a coloring agent approved for food use the remainder to 100% being water or a water-alcohol mixture.

12. Lid material (40, 46) according to any of the preceding claims 9 - 11 , wherein the thickness of the lid material including the heat-sealing composition coating is in the range of 120-500 pm, preferably in the range of 200-400, most preferably in the range of 250-300 pm.

13. Lid material (40, 46) according to any of the preceding claims 9 to 12, wherein the lid material, on the side opposite to the heat-sealing coating, is provided with a filter layer.

14. Method for producing a sealed coffee capsule containing ground coffee for single portion extraction, wherein a container (10,20) according to any of claims 1-8 is provided in a first step, in a second step the interior of said container is filled with ground coffee, and in a third step lid material (40, 46) according to any of claims 9-13 is attached to the rim of the coffee capsule with its heat-sealing composition coated side facing the interior of the coffee capsule by applying heat and/or pressure from the backside of said rim and/or from the side facing away from the heat-sealing composition coated side of the lid material at least in the rim area.

15. Sealed coffee capsule containing ground coffee for single portion extraction, with a container (10,20) according to any of claims 1-8 and a lid material (40, 46) according to any of claims 9-13, preferably obtained in a process according to claim 14.