IT201800009622A1 - PROCEDURE FOR MAKING A COMPOSTABLE POD FROM INFUSION, COMPOSTABLE POD SO OBTAINED AND RELATIVE STRUCTURAL ELEMENT - Google Patents

Description

PROCEDURE FOR MAKING A COMPOSTABLE INFUSION POD, SO COMPOSTABLE POD

OBTAINED AND RELATIVE STRUCTURAL ELEMENT

The present invention is part of the field of compostable infusion pods.

More precisely, it refers to a compostable pod, made thanks to the use of an improved process of processing a compostable film and the possible insertion of a relative support structure.

There are compostable pods on the market, which consist of two heat-sealed layers, between which the coffee or other infusion product is positioned. These pods, however, have the drawback that they are not very resistant to perforation and / or tearing.

For this reason, it is necessary to use rather thick layers, with obvious consequent waste of material.

There remains therefore the need to obtain compostable pods for infusion, which are resistant to tearing and accidental perforation.

The aim of the present invention is therefore to obviate the aforementioned drawbacks and, in particular, to make a compostable infusion pod, using materials that are adaptable and usable for making compostable pods using standard machinery already present on the market. Another object of the present invention is that of realizing a compostable pod and its relative structure, which allows an easy insertion of the infusion material and a consequent conservation.

A further purpose of the invention is to create a compostable infusion pod, which is resistant to tearing and accidental perforations during the manufacturing and / or storage and transport phases.

These and other objects are achieved by a process for the production of a compostable infusion pod, according to the attached claim 4, a compostable pod and its relative structure, according to the attached claims 1 and 7; other detailed characteristics of the device are reported in the dependent claims.

Therefore, the subject of the present invention is a compostable structural element, for a compostable infusion pod, comprising an annular main body and a series of alveoli with an entrance facing towards the inside of the main body.

This structural element therefore advantageously has a reduced volume and gives the pod that will contain it a consistency necessary for its use within infusion dispensing machines, without compromising its compostability.

According to the invention, first and / or second alveoli can be provided, which present, on one side parallel to the main development plane of the main body, an opening; for example, said first alveoli can be open towards a first direction, while the second alveoli can be open towards a second direction.

This advantageously allows a uniform distribution of the infusion material inside the pod, in order to facilitate the infusion of all the ingredients during the dispensing of the drink.

In this case, according to the invention, these first and second alveoli can be arranged alternately along the main body.

A further object of the present invention is a process for making a compostable pod containing infusion material, comprising the following steps:

• provide a compostable film obtained by coupling a first layer of PLA with a second layer based on corn starch, in a weight between 98gr and 130gr;

• dispense vaporized edible liquid on the first layer of the compostable film;

• draw the hot compostable film, until two or more recesses are obtained on the film so that the first layer faces the inside of the recess and the second layer faces the outside of the recess;

• insert the infusion material in predetermined quantities into one or more of said two or more recesses, so as to have at least a first recess, equipped with infusion material inside it and at least a second recess, free from material from infusion inside it;

• select a first groove and a second groove and couple them together;

• cold welding said first second grooves;

• cut the edge of said hollows along an abutment, until obtaining a compostable infusion pod.

This advantageously allows to obtain a compostable wafer with satisfactory performance on the basis of the parameters which will be explained below.

In detail, the process of the invention can provide, after the step of inserting the infusion material in predetermined quantities into one or more of said two or more recesses, and before the step of selecting a first recess and a second recess and couple them together, the following phase:

• press the infusion material.

This becomes extremely advantageous if the chosen infusion material is a blend of coffee powders or the like, which under pressure are able to give the pod a structure that allows it to be used in dispensing machines. of infused beverages, without loss of efficiency or material.

Alternatively, again according to the invention, the process can provide, after the step of drawing the hot compostable film and before the step of inserting the infusion material in predetermined quantities into one or more of said two or more recesses. , the following phase:

insert a structural element in one or more of said two or more recesses as indicated above.

In this way, in fact, the same type of materials and production phases can also be applied advantageously to the production of compostable pods in which the chosen infusion material is based on a mixture of leaves and / or flowers for tea or in any case for infusion. , which under pressure would not be able to give the wafer the required structure. The presence of the structural element, on the other hand, makes up for this lack, while still maintaining the possibility of using the pod even in machines for dispensing infused beverages without loss of efficiency or material.

A further object of the invention is a compostable infusion pod characterized by the fact that it is made using this procedure.

Further objects and advantages of the present invention will become clearer from the following description, relating to an exemplary and preferred, but not limiting, embodiment of the process for the production of a compostable infusion pod, of the compostable pod and of the relative structure, according to the present invention, and from the attached figure 1 which shows a perspective view of a preferred embodiment of the structure for the compostable infusion pod, according to the invention, when resting on a horizontal plane.

Advantageously, the compostable film chosen for the production of a compostable infusion pod of the invention is made by the company Ahlstrom Munkjo, and is obtained by coupling two different films: for the internal part of the pod a film with a PLA base , for the external part of the wafer a parchment based on corn starch.

PLA (poly-lactic acid) or polylactic acid is a polymer derived from corn, wheat or beet, rich in natural sugars (dextrose). These sugars, through a fermentation process, convert into lactic acid and can therefore be used to produce different types of resins.

Parchment is made from corn starch and other natural raw materials. The peculiarity of the latter is its resistance to atmospheric agents: in fact, by immersing the parchment in a special edible liquid mixture, this, at the molecular level, acquires the barrier that protects it from oxygen.

This procedure implies that the parchment assumes not very elastic mechanical characteristics.

By coupling the two materials, a single barrier film is obtained, with particular characteristics, namely resistance to both mechanical pressure and temperature and a considerable degree of elasticity.

Starting from the creation of a compostable wafer, using the compostable Ahlstrom film, various tests were carried out, on films with different weights and thicknesses, to verify the characteristics of the material.

A 98gr film (grams refer to the square meter) was initially used, not barrier, i.e. not resistant to oxygen: this film allows the oxygen molecules to penetrate inside the pod, consequently modifying and altering the organoleptic qualities of coffee. The material was modeled using a hot thermoforming machine.

The film responded optimally on low cycle times, but using higher speeds some cracks were found on the outside of the film.

By humidifying the film, before thermoforming it, the problem of breakage was also solved by using higher processing speeds. This provided additional data that allowed the final manufacturing process to be developed.

Using the same technique, ie humidifying the film and making changes concerning the temperature of the molding machine, other tests with different weight and thickness were made, in this case 130, but with a barrier. The expression "barrier", on the other hand, identifies a film that does not give rise to transfers of matter to the food - in our case, coffee - through migration and / or transfer, infiltrations and naturally oxidation due to contact with the air (which contains oxygen). The result was positive and the material responded optimally.

The table below shows the tests carried out with different types of compostable paper

• There is no phase with PLA

• The paper has always been moistened before the test, except for the no. 8

Table with the tests carried out with humidified film:

130 YES 50 max 130 NO

130 YES 50 max 130 NO

The tests show that the film is drawn only if it is previously humidified. Consequently, the machine is equipped with a steam nebulizer which applies distilled water to the internal part of the compostable film. Subsequently the film is thermoformed by a hot drawing machine with temperature variation.

This procedure ensures that the compostable film does not alter its characteristics.

In fact, the water creates a thin protective layer that allows the pad that it draws not to crystallize - and therefore not to break - the film, since the drawing speed is such that it acts only on the wet layer and not on the film itself.

The film therefore maintains - without altering - its elastic characteristics, thus allowing it to be drawn without problems.

WELDING PROCESS

Once the coffee pod was created, it was introduced inside the two deep-drawing.

It is now possible to move on to the second phase of the process: welding.

Two different welding strategies were evaluated: one hot and one using ultrasound.

The first welding used is the hot one, that is through a mechanical welder, which uses an internal electric resistance adjustable by means of a temperature probe that indicates the reading in degrees. This process generates these results:

• Stiffness of the outer crown

• Crystallization of the material

• Weakening of the product structure

• Poor watertightness

• Alteration of the mechanical characteristics of the film.

The second, and certainly the safest, is the ultrasonic one: using two ultrasonic generators (20 khz Telsonic and 30 khz Herrmann) with a component called - in this case - bell-shaped sonotrode at the end, it was possible to perform different welds.

Ultrasound welds without overheating the product and the fusion of the welded materials occurs at the molecular level.

This process generates these results:

• Does not alter the elasticity characteristics of the film

• It does not crystallize the outer crown as the welding is cold

• Excellent watertightness

• Speeds up the machining process

TEST AND ANALYSIS ON THE AND COFFEE PRODUCTS

Tests were carried out on both coffee and tea. For the coffee, a mechanical press is used in line with the pod production plant, which forms the pod directly inside the previously carried out semi-drawing of the film, respecting the specific measures for compatibility with certain infusion machines of different manufacturers. producers. After being drawn, in fact, a half-moon of compostable film is obtained, which then passes under a screw dispenser, which drops the right amount of coffee: between 6.2 and 6.5 grams. Subsequently, the semiluna passes under the mechanical press unit which, through a forming cylinder, forms the pod and at the same time sucks up any coffee residues on the film outside the pod, to advantageously ensure that the ultrasonic sealing is effective and free of residues. of coffee.

For tea, on the other hand, the process further requires a particular insert, made of polypropylene and / or compostable material.

This insert is housed inside the compostable film half moon and is then filled with the dose of tea which is indicative for each blend used. At this point, the filled crescent does not require any pressing. After filling with the established quantity, in fact, the filled half moon is coupled to the other half moon obtained by drawing another portion of film and finally they are welded together.

Several rings with different characteristics have been used and approved:

• Polypropylene single ring without internal groove

• Simple ring with internal polypropylene groove

• Polypropylene machined ring

• PLA machined ring

In detail, with reference to Figure 1, in a preferred embodiment the ring, generically indicated with the numerical reference 10, can have a honeycomb structure facing inwards, so as to minimize the volume 11 of the ring. In fact, the series of alveoli 1, 2, leave room for the infusion material to move and rest freely within the crescent of the wafer. This type of structure given by the ring 10 and its alveoli 1, 2 at the same time maintains sufficient rigidity to support the pod, without it breaking or falling apart during use inside the brewing machine.

Preferably, in more detail, the alveoli 1, 2 obtained on the inner surface of the ring are open below and / or above, considering the ring resting on a horizontal plane.

In other words: there may be first alveoli 1, facing towards the inside of the ring 10 and open at the bottom, and / or second alveoli 2, always facing towards the inside of the ring 10 and open at the top. This advantageously allows for a more efficient dispensing of the drink, having a larger surface for infusion and a better mechanical structure.

In addition, the ring structure is advantageous for the realization of the same, since it can be obtained from a male / female mold.

Its internal processing, with access to the alveoli perpendicular to the delivery flow of the infused drink, allows the ring not to deform during this last phase, ensuring excellent structural stability throughout the process.

Furthermore, the alveoli 1, 2 of the ring 10 can be opened alternately at the top and at the bottom, so as to use as little material as possible, while maintaining the advantages described above.

These solutions allow you to insert quantities of infusion material both for single doses (from 1.2 to 2 g), for example to dispense about 120 ml of tea, and for double-dose pods, for example to dispense about 240 ml of tea, and therefore coming to accommodate up to 4.5 gr of ground product inside the ring.

FINAL CONCLUSIONS

In conclusion, to obtain a compostable pod, for example compatible with a machine of the type known by the trade name of Nespresso professional, the following procedure must be performed:

For the Coffee:

• Deep-draw the compostable Ahlstrom film (98gr 130gr) using the drawing process indicated above, in order to obtain film half-moons • Dose the coffee using an auger doser (from 6.2gr to 6.6gr)

• Form the coffee pod using a press, preferably in line

• Couple two half-moons of drawn film

• Cold welding with the aid of the 20 or 30 khz sonotrode

• Offset blanking to obtain the finished product.

For the tea:

• Draw the compostable Ahlstrom film (98gr 130gr) using the required drawing process • Insert the ring using a lateral pick and place

• Dose the tea according to the required characteristics

• Couple the other half-drawing

• Cold welding with the aid of the 20 or 30 khz sonotrode

• Offset blanking to obtain the finished product.

The advantages of the process for the production of a compostable infusion pod of the present invention have thus been ascertained.

From the description made, the characteristics of the compostable infusion pod and its structure are so clear, which are also the subject of the present invention, as are the advantages.

Finally, it is clear that numerous other variations can be made to the process, to the wafer and to the structure in question, without thereby departing from the novelty principles inherent in the inventive idea, just as it is clear that, in the practical implementation of the invention , the materials, shapes and dimensions of the illustrated details may be any according to requirements and the same may be replaced with other equivalents.

Claims (7)

CLAIMS 1. Compostable structural element (10) for compostable infusion pod, characterized in that it comprises a main body (11) with an annular conformation and a series of cells (1,2) with inlet facing towards the inside of the main body (11 ). 2. Structural element (10) according to claim 1, characterized in that it provides first cavities (1) and / or second cavities (2), the first cavities (1) having a side parallel to the main development plane of the main body ( 11) open towards a first direction, the second alveoli (2) having a side parallel to the main development plane of the main body (11) open facing towards a second direction, opposite to the first direction. Structural element (10) according to claim 2, characterized in that it has first cavities (1) and second cavities (2) arranged alternately along the main body (11). 4. Process for making a compostable pod containing infusion material, comprising the following steps: • provide a compostable film obtained by coupling a first layer of PLA with a second layer based on corn starch, in a weight between 98gr and 130gr; • dispense vaporized edible liquid on the first layer of the compostable film; • draw the hot compostable film, until two or more recesses are obtained on the film so that the first layer faces the inside of the recess and the second layer faces the outside of the recess; • insert the infusion material in predetermined quantities into one or more of said two or more recesses, so as to have at least a first recess, equipped with infusion material inside it and at least a second recess; • select a first groove and a second groove and couple them together; • cold welding said first and second grooves; • cut the edge of said hollows along an abutment, until obtaining a compostable infusion pod. 5. Process for making a compostable pod according to claim 4, characterized in that, after the step of inserting the infusion material in predetermined quantities into one or more of said two or more recesses, and before the step to select a first groove and a second groove and couple them together, the following phase is foreseen: • press the infusion material. 6. Process for making a compostable wafer according to claim 4, characterized in that, after the step of drawing the hot compostable film and before the step of inserting the infusion material in predetermined quantities, the following phase is foreseen: • inserting in one or more of said two or more recesses a structural element (10) according to one of claims 1-3. 7. Compostable pod for infusion characterized in that it is made by means of the process according to one of claims 4-6.