Method for manufacturing a capsule intended to receive a substance for preparing a beverage

Abstract

The invention relates to a method for manufacturing a capsule (1) intended to receive a substance (S) for preparing a beverage, the method comprising the steps of: forming a body (1a) having a lateral wall bordered on either side by a base and an upper opening, respectively; bonding, by thermoforming, a coating film (5) on the inner surface of the lateral wall, the film having a lower portion arranged opposite the base; forming a lower opening (6) through the base by cutting the lower portion; and closing the lower opening by means of a lower seal (7).

Description

[0001] Method of manufacturing a capsule intended to receive a substance for the of a drink

[0002] The invention relates to a method for manufacturing a capsule intended to receive a substance for preparing a beverage, as well as a capsule manufactured by implementing such a method.

[0003] Capsules are known comprising a body defining a compartment for packaging the substance in said capsule, said body having a side wall bordered on either side by a bottom and an upper opening respectively.

[0004] After the capsule has been manufactured, the substance for preparing a beverage is introduced into the compartment through the upper opening, which is then closed, in particular by sealing an upper seal on a rim surrounding said opening.

[0005] In particular, to preserve the organoleptic properties of the substance over time, the capsule, once closed, must have good barrier properties against oxygen and humidity in the air.

[0006] Such capsules are intended in particular for the preparation of a hot drink such as coffee, tea or infusion. To do this, a capsule is installed in the housing of a machine provided for this purpose, where it is held by a piston while an extracting fluid, for example hot water, passes through it and the substance it contains.

[0007] To do this, the piston comprises means for injecting pressurized fluid into the compartment by piercing the bottom of the capsule, the flow of the beverage through the upper opening being obtained by breaking the upper seal under the effect of the pressure of the extracting fluid in the compartment, in particular by pressing said seal onto a grid of the machine by means of the piston.

[0008] REPLACEMENT SHEET (RULE 26) The body of the capsules is conventionally formed by stamping a sheet of metal material, particularly aluminum, whose mechanical properties are well suited to piercing the base, in particular without risking crushing the capsule. However, such capsules are expensive to produce, in addition to being difficult to recycle.

[0009] To improve the environmental impact of their use, capsules have been developed with a body made from a biodegradable and compostable material, both industrially and domestically. In particular, compostable plastics or cellulose-based materials are used.

[0010] However, particularly with cellulose capsules, it is preferable to cover the inner surface of the compartment with a coating film which, by avoiding direct contact between the packaged substance and the body of the capsule, preserves said substance from aromatic pollution by the material of said body.

[0011] Furthermore, good organoleptic preservation of the substance packaged in the capsule can be obtained with a coating film having oxygen and / or moisture-proof properties, and / or by covering the body of the capsule with a label having such properties.

[0012] However, the mechanical properties of the materials used to form the capsules may not be sufficient to guarantee piercing of the base without deformation which could induce detachment of the coating film and therefore a risk of said film not being pierced by the injection means. In addition, the mechanical properties of the coating films, in particular their elasticity, do not guarantee their piercing.

[0013] The invention aims to improve the prior art by proposing a method for manufacturing a capsule whose body can be formed from a material

[0014] REPLACEMENT SHEET (RULE 26) having a limited ecological impact, while guaranteeing preservation of the organoleptic properties of the substance over time and optimal piercing of the bottom of said capsule in order to make the injection of the extracting fluid into the packaging compartment of said substance more reliable.

[0015] To this end, according to a first aspect, the invention proposes a method of manufacturing a capsule intended to receive a substance for the preparation of a beverage, said method providing:

[0016] - forming a body defining a compartment for packaging the substance in said capsule, said body having a side wall bordered on either side by a bottom and an upper opening respectively;

[0017] - associating by thermoforming a coating film on the inner surface of the side wall of the body, said film having a lower portion arranged opposite the bottom;

[0018] - forming a lower opening through the bottom by cutting out said lower portion, said lower opening being intended to be crossed by means for injecting an extractor fluid from a beverage preparation machine to inject said fluid under pressure into the compartment;

[0019] - closing said lower opening by means of a lower cover, said lower cover being adapted to be pierced by the injection means.

[0020] According to a second aspect, the invention proposes a capsule manufactured by implementing such a method, said capsule comprising a body defining a compartment for packaging a substance for preparing a beverage, said body having a side wall bordered on either side by a bottom having a lower passage and an upper opening, the inner surface of the side wall of the body being covered with a coating film having a lower cutout arranged opposite said passage to form a lower opening intended to be crossed by means for injecting an extracting fluid of a beverage preparation machine to inject said fluid under pressure into the compartment, said

[0021] SUBSTITUTE SHEET (RULE 26) lower opening being closed by means of a lower seal which is adapted to be pierced by said injection means.

[0022] Other features and advantages of the invention will appear in the following description, given with reference to the appended figures, in which:

[0023] - figures 1a and 1b represent respectively in exploded perspective (figure 1a) and in exploded longitudinal section (figure 1b) a capsule during the implementation of a manufacturing method according to the invention;

[0024] - figure 2 represents in exploded longitudinal section a capsule according to an embodiment of the invention.

[0025] In relation to these figures, a capsule 1 is described below intended to receive a substance S for the preparation of a drink, said capsule having a body 1a defining a compartment for packaging said substance.

[0026] In order to facilitate the treatment of waste containing capsules 1, the body 1a is preferably made from a compostable material according to standard EN 13432.

[0027] In particular, the material constituting the body 1a of the capsule 1 can be chosen to allow both industrial and domestic composting, and can be biodegradable. According to one embodiment, the body 1a of the capsule 1 is made by injection of a plastic material based on polylactic acid (PLA) or Polyhydroxyalkanoate (PHA), insofar as these materials, in addition to being compostable and compatible with food substances, make it possible to easily produce capsules 1 with thin walls by injection, and which do not deform under the effect of heat.

[0028] According to a preferred embodiment, the body 1a of the capsule 1 is formed from cellulose, in particular by molding a cellulose pulp, and preferably contains exclusively cellulose, in particular 100% from sustainable and / or organic agriculture.

[0029] SUBSTITUTE SHEET (RULE 26) Thus, an easily recyclable capsule 1 can be manufactured inexpensively and with high yield, with reduced carbon dioxide emissions, particularly compared to injection molding of a plastic material.

[0030] Furthermore, the exclusive use of cellulose makes it possible to obtain a capsule 1 whose body 1a can be easily composted, both industrially and domestically, in particular with a reduced composting time (of the order of one month) compared to the average composting time of capsules made of compostable molded plastic (approximately 6 months).

[0031] According to one embodiment, the body 1a of the capsule 1 is formed by dry molding of a sheet of cellulose pulp, which makes it possible to considerably increase the manufacturing yield of the capsule 1 while limiting the number, size and cost of the necessary installations, as well as water and energy costs.

[0032] In particular, the dry molding formation of the body 1a of the capsule 1 provides for forming a sheet of cellulose pulp, then thermoforming the capsule 1 by hot molding said sheet. In relation to FIG. 2, the sheet may comprise an outer layer 11 supporting the cellulose pulp which is molded to form the body 1a.

[0033] According to another embodiment of manufacturing by dry molding of the body 1a of the capsule 1, it is planned to form the sheet in the form of a sheet of cellulose pulp, having in particular a thickness of between 0.5 and 1 mm, for example of the order of 0.75 mm. In particular, the sheet can be based on cellulose pulp of the NBSK type (Northern Bleached Softwood Kraft).

[0034] Advantageously, the sheet may be wetted, for example by spraying water on the surface, before thermoforming, in order to improve its molding capacity while allowing the evaporation of the water during thermoforming. According to another embodiment, the body 1a of the capsule 1 may be formed by wet molding, that is to say by the preparation of a paste comprising cellulose pulp suspended in water, the capsule 1 being formed with said paste before its drying.

[0035] Advantageously, the cellulose forming the body 1a of the capsule 1 comprises microfibrillated cellulose (MFC), in particular between 1% and 50% by weight of MFC microfibrillated cellulose.

[0036] Microfibrillated cellulose (MFC) consists of individual cellulose microfibrils or aggregates. These microfibrils are typically 2 to 20 nanometers in diameter and a few micrometers long. Microfibril aggregates are composed of several cellulose microfibrils agglomerated together.

[0037] In relation to the figures, the body 1a of the capsule 1 has a side wall 2 bordered on either side by respectively a bottom 3 and a rim 12 surrounding an upper opening 4, said body having a geometry of revolution around a central axis forming a side wall 2 which is generally inscribed in a truncated cone with a right generatrix between the bottom 3 and the upper rim 12.

[0038] The capsule 1 is intended to be equipped with an upper cover 13 which is associated with the rim 12 to cover the opening 4, forming in the body 1a a compartment for packaging the substance S.

[0039] The upper opening 4 allows the loading of the substance S into the compartment which is closed opposite by the bottom 3, said opening then being closed by the upper cover 13 after said loading.

[0040] The capsule 1 is intended in particular for the preparation of a hot beverage such as coffee, tea or infusion. To do this, the capsule 1 is installed in the housing of a machine provided for this purpose, where it is held by a piston while an extracting fluid, for example hot water, passes through it and the substance S it contains.

[0041] To do this, the piston comprises means for injecting pressurized fluid into the compartment by piercing the bottom 3 of the capsule 1, the flow of the beverage through the upper opening 4 being obtained by breaking the upper seal 13 under the effect of the pressure of the extracting fluid in the compartment, in particular by pressing said seal onto a grid of the machine by means of the piston.

[0042] During the preparation of the beverage, the capsule 1 is subjected to an injection of water at a temperature of between 86°C and 90°C and under a pressure of up to 20 bars, for a duration of approximately 2 minutes. In particular, to prepare a coffee-type beverage, the quantity of water injected into the capsule 1 is between 40 mL and 150 mL.

[0043] After forming the body 1a of the capsule 1, the method provides for associating by thermoforming a coating film 5 on the inner surface of the side wall 2 of said body. Alternatively, the film 5 can be associated jointly with the thermoforming of the body 1a.

[0044] The coating film 5 may be based on thermoplastic polymers, for example PBS (Poly(Butylene Succinate)), which are compostable and advantageously biodegradable, said film having properties, in particular softening and elongation, allowing it to be thermoformed.

[0045] In particular, the coating film 5 is arranged to avoid direct contact between the packaged substance S and the body 1a of the capsule 1, in order to protect said substance from aromatic pollution by the material of said body.

[0046] Conventionally, for its thermoforming, the coating film 5 is heated to a temperature sufficient to allow it to be pushed into the compartment of the body 1a, in particular under vacuum and / or using a punch, with a view to shaping it against the interior surface of said compartment,

[0047] In particular, the covering film 5 comprises an outer layer formed from a thermoplastic material, the thermoforming of said film being carried out at a temperature, for example less than 140°C, which is higher than the melting temperature of said material, so as to ensure the sealing of said layer on the inner surface of the side wall 2 of the body 1a.

[0048] After thermoforming, the covering film 5 has a lower portion which is arranged opposite the bottom 3, said lower portion closing the lateral portion of said film which is associated with the lateral wall 2 of the body 1a.

[0049] The method of manufacturing the capsule 1 provides for forming a lower opening 6 through the base 3 by cutting the lower portion of the coating film 5, said lower opening being intended to be crossed by means for injecting an extractor fluid from a beverage preparation machine to inject said fluid under pressure into the compartment.

[0050] In particular, the cutting in the coating film 5 makes it possible to overcome its possible difficulty in being pierced by the injection means, in particular in that said film has an elasticity necessary for its thermoforming. In relation to the figures, the cutting is carried out so as to form a lower opening 6 over substantially the entire dimension of the bottom 3 of the body 1a of the capsule 1.

[0051] The method provides for closing the lower opening 6 by means of a lower cover 7, said lower cover being adapted to be pierced by the injection means.

[0052] In particular, the lower cover 7 is arranged to be easily passed through by the injection means, in particular more easily than a solid bottom 3 of the body 1a of a capsule 1, a fortiori coated with the film 5, in order to limit the risks of deformation of said capsule during its use.

[0053] Thus, it is possible, in particular for a capsule 1 formed from a material having a limited ecological impact, to combine the preservation of the organoleptic properties of the substance S over time and optimal piercing of the base 3 of said capsule for its use.

[0054] In particular, the body 1a of the capsule 1 thus obtained has a side wall 2 bordered on either side by a bottom 3 having a lower passage 8 and an upper opening 4, the inner surface of the side wall 2 of the body 1a being covered with a coating film 5 having a lower cutout 10 arranged opposite said passage to form a lower opening 6 intended to be crossed by means for injecting an extracting fluid of a beverage preparation machine to inject said fluid under pressure into the compartment, said lower opening being closed by means of a lower cover 7 which is adapted to be pierced by said injection means.

[0055] In relation to figures 1a and 1b, the lower passage 8 of the bottom 3 of the capsule 1 and the lower cutout 10 of the coating film 5 have a similar circular geometry, said lower passage being bordered by a conical rim 8a on which the corresponding edge 10a of the lower cutout 10 is associated. Furthermore, the film 5 has a crown 14 fixed to the rim 12 of the upper opening 4 by covering it, the upper cover 13 being associated, in particular by sealing, on said crown.

[0056] According to one embodiment, the body 1a is formed with a lower wall forming the bottom 3, the formation of the lower opening 6 comprising a cutout of said lower wall to form the lower passage 8 through said bottom, and the cutting, in particular jointly, of the lower portion of the film 5 at least opposite said passage. According to another embodiment, the bottom 3 of the body 1a is formed with an open lower passage 8, the lower portion of the film 5 being cut out at least opposite said passage to form the lower opening 6.

[0057] In relation to figure 2, the lower cover 7 is associated at the periphery of the lower opening 6. In particular, the lower cover 7 can be associated with the body 1a of the capsule 1, in particular on the outside of the conical rim 8a surrounding the passage 8.

[0058] According to another embodiment, possibly complementary, the lower cover 7 is associated with the covering film 5, said lower cover then being able to be arranged in the packaging compartment. In particular, the lower cover 7 can be associated on the inside of the edge 10a of the lower cutout 10.

[0059] Advantageously, the covering film 5 comprises an inner layer formed from a thermoplastic material, the lower seal 7 being sealed to said layer at a temperature, for example greater than 140°C, which is higher than the melting temperature of said material. According to one embodiment, the covering film 5 comprises two layers, respectively upper and lower, which are associated with each other, in particular by co-extrusion.

[0060] The lower seal 7 may comprise a lower layer formed from a thermoplastic material, said lower layer being sealed to the film 5 at a temperature, for example greater than 140°C, which is greater than the melting temperature of said material.

[0061] Advantageously, the melting temperature of the material of the outer layer of the coating film 5 is lower than the melting temperature of the material of the lower layer of the lid 7 and / or of the inner layer of said film. In order to be able to preserve the organoleptic characteristics of the substance S packaged before its use for preparing a beverage, the capsule 1 must be leaktight, in particular by forming a barrier against the circulation of oxygen and moisture, both towards the inside of said capsule, to prevent the substance it contains from being altered by the ambient air and moisture, and towards the outside, in particular to prevent the drying out of a substance S packaged in a moist and / or greasy form.

[0062] In particular, to ensure optimal conservation of substance S, capsule 1 has the following characteristics:

[0063] - an oxygen transmission rate of less than 10 cm3 / m 2 .day.atm, in particular of at most 5 cm 3 / m 2 .day.atm, and more particularly less than 1 cm 3 / m 2 .day.atm, measured according to ASTM D3985;

[0064] - a water vapor transmission rate of less than 60 g / m 2 .24h, and more particularly less than 10 g / m 2 .24h, measured according to ASTM E96 standard in tropical conditions (38°C and 90% humidity).

[0065] With such characteristics, capsule 1 can notably be stored:

[0066] - before filling with a substance S for preparing a beverage: at a temperature between 15 and 25°C, and up to 50°C for a maximum period of 6 weeks during transport;

[0067] - after filling: in a dry and temperate place, with a maximum ambient humidity level between 35 and 55%.

[0068] Advantageously, the body 1a of the capsule 1 is subjected to a preliminary treatment to close the pores of the cellulose sheet constituting it, in order to form a first barrier against oxygen and water vapor.

[0069] Furthermore, the use of a cellulose pulp comprising microfibrillated cellulose MFC contributes favorably to the sealing of the capsule 1 against oxygen and water vapor. However, to the extent that the material constituting the body 1a of the capsule 1 would not have sufficient performance, in particular due to the porosity of the cellulose, the side wall 2 can be covered with a sealing label 9 and / or a sealing coating forming a second barrier against oxygen and / or humidity.

[0070] The coating and / or the sealing label 9 may be applied to the side wall 2, not only to reinforce its barrier properties to oxygen and / or water vapor, but also to provide it with additional barrier properties, in particular lipophobic properties, in order to further preserve the organoleptic properties of the substance S packaged in the capsule 1.

[0071] In relation to Figure 2, a label 9 is provided to cover the outer surface of the side wall 2 of the body 1, said label having oxygen and / or moisture sealing properties which are superior to those of the covering film 5, in particular in that said film is devoid of a sealing layer.

[0072] Likewise, the lids 7, 13 make it possible to ensure a watertight closure of the capsule 1, in particular by forming a barrier against oxygen and humidity, the lower lid 7 being able to be made with the same film as the sealing label 9, and the upper lid 13 in a film according to document WO-2022 / 112613.

[0073] The sealing label 9 may be associated with the side wall 2 during or after the molding of the body 1a of the capsule 1, according to an IML (In-Molding Process) process, during which said label is placed against a side wall of a molding cavity of said body before effective production of said molding, so as to simultaneously carry out the steps of forming said body and associating said label with its side wall 2. Alternatively, the label 9 may be associated by thermoforming. The sealing label 9, and more generally the film constituting said label and the lids 7, 13, may be formed in a sealing film comprising cellulose, in particular comprising microfibrillated cellulose MFC.

[0074] In particular, the sealing film comprises at least one layer based on microfibrillated cellulose MFC. Advantageously, the MFC layer may be in the form of a paper layer formed with microfibrillated cellulose so as to be highly fibrillated, and may in particular be translucent, so as to be able to be a particularly barrier to oxygen.

[0075] Furthermore, the use of a cellulose pulp comprising microfibrillated cellulose MFC contributes favorably to the association of the label 9 on the side wall 2, in particular by limiting the granulosity of said wall.

[0076] According to exemplary embodiments, the MFC layer has:

[0077] - a thickness between 30 and 70 pm; and / or

[0078] - a surface mass between 40 and 90 g / m 2 .

[0079] The MFC layer makes it possible to obtain a sealing film with a high surface mass and sufficient oxygen tightness for the barrier function, while being perfectly biodegradable and / or compostable.

[0080] The sealing film may have been treated to improve its resistance to moisture, for example by means of the sealing coating, applied in the form of a lacquer or by metallization of said film.

Claims

CLAIMS 1. Method for manufacturing a capsule (1) intended to receive a substance (S) for the preparation of a beverage, said method providing: - forming a body (1a) defining a compartment for packaging the substance (S) in said capsule, said body having a side wall (2) bordered on either side by a bottom (3) and an upper opening (4) respectively; - associating by thermoforming a coating film (5) on the inner surface of the side wall (2) of the body (1a), said film having a lower portion arranged opposite the bottom (3); - forming a lower opening (6) through the bottom (3) by cutting out said lower portion, said lower opening being intended to be crossed by means for injecting an extracting fluid from a beverage preparation machine to inject said fluid under pressure into the compartment; - closing said lower opening by means of a lower cover (7), said lower cover being adapted to be pierced by the injection means.

2. Method of manufacturing a capsule (1) according to claim 1, characterized in that the body (1a) is formed with a lower wall forming the bottom (3), the formation of the lower opening (6) comprising a cutting of said lower wall to form a lower passage (8) through said bottom, and the cutting of the lower portion of the film (5) at least opposite said passage.

3. Method for manufacturing a capsule (1) according to claim 1, characterized in that the bottom (3) of the body (1a) is formed with an open lower passage (8), the lower portion of the film (5) being cut at least opposite said passage to form the lower opening (6).

4. Method for manufacturing a capsule (1) according to any one of claims 1 to 3, characterized in that the body (1a) is formed from cellulose.

5. Method for manufacturing a capsule (1) according to claim 4, characterized in that the body (1a) is formed by dry molding of a sheet of cellulose pulp or by wet molding of a paste comprising cellulose pulp suspended in water.

6. Method for manufacturing a capsule (1) according to any one of claims 1 to 5, characterized in that the lower cover (7) is associated at the periphery of the lower opening (6).

7. Method for manufacturing a capsule (1) according to any one of claims 1 to 6, characterized in that the lower cover (7) is associated with the body (1a) of the capsule (1).

8. Method for manufacturing a capsule (1) according to any one of claims 1 to 7, characterized in that the lower cover (7) is associated with the coating film (5).

9. Method for manufacturing a capsule (1) according to claim 8, characterized in that the lower cover (7) is arranged in the packaging compartment of the substance (S).

10. Method of manufacturing a capsule (1) according to one of claims 8 or 9, characterized in that the coating film (5) comprises an inner layer formed from a thermoplastic material, the lower cover (7) being sealed on said layer at a temperature higher than the melting temperature of said material.

11. Method for manufacturing a capsule (1) according to any one of claims 8 to 10, characterized in that the lower cover (7) comprises a lower layer formed from a thermoplastic material, said lower layer being sealed to the film (5) at a temperature above the melting temperature of said material.

12. Method for manufacturing a capsule (1) according to any one of claims 1 to 11, characterized in that the coating film (5) comprises an outer layer formed from a thermoplastic material, the thermoforming of said film being carried out at a temperature higher than the melting temperature of said material, so as to ensure the sealing of said layer on the inner surface of the side wall (2) of the body (1a).

13. Method for manufacturing a capsule (1) according to any one of claims 1 to 12, characterized in that it further provides for covering the outer surface of the side wall (2) of the body (1) with a label (9) for sealing against oxygen and / or humidity.

14. Method for manufacturing a capsule (1) according to claim 13, characterized in that the sealing label (9) is associated with the side wall (2) during or after the formation by molding of the body (1a) according to an IML process.

15. Capsule (1) manufactured by implementing a method according to any one of claims 1 to 14, said capsule comprising a body (1a) defining a compartment for packaging a substance (S) for the preparation of a beverage, said body having a side wall (2) bordered on either side by a bottom (3) having a lower passage (8) and an upper opening (4), the inner surface of the side wall (2) of the body (1a) being covered with a coating film (5) having a lower cutout (10) arranged opposite said passage to form a lower opening (6) intended to be crossed by means for injecting an extractor fluid of a beverage preparation machine to inject said fluid under pressure into the compartment, said lower opening being closed by means of a lower cover (7) which is adapted to be pierced by said injection means.

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