FR2971240A1 - PACKAGING AND / OR INSULATION MATERIAL, PROCESS AND METHOD FOR MANUFACTURING THE SAME - Google Patents

Abstract

The invention relates to a packaging material and / or insulation (1) biodegradable, expanded and made from at least one product of plant origin and at least one plasticizer, said material (1) being characterized in that said at least one plasticizer comprises at least water and gives said material (1) shaping properties by a thermoforming process. Packaging and / or insulation materials.

Description

INSULATED PACKAGING MATERIAL, PROCESS AND METHOD FOR MANUFACTURING THE SAME

The present invention relates to the general technical field of packaging or packaging materials, especially in the cosmetics, food and / or pharmaceutical field, as well as to the technical field of insulation materials, for example thermal insulation and / or or phonic in the field of construction.

The present invention relates more particularly to an environmentally friendly packaging and / or insulation material, in particular because of its composition based on vegetable matter and its biodegradability.

The present invention relates to a packaging material and / or insulation biodegradable, expanded and made from at least one product of plant origin and at least one plasticizer.

The present invention also relates to a method of manufacturing a packaging and / or insulation material comprising a step of mixing at least one product of plant origin with at least one plasticizer and an expansion step.

The present invention finally relates to a machine for manufacturing a packaging and / or insulation material comprising an extruder designed to allow extrusion of a mixture comprising at least one product of vegetable origin and at least one agent. plasticizer.

In the field of packaging, and in particular food packaging, it is known to use trays made of expanded polystyrene in which food is packaged. In general, these expanded polystyrene trays are used to package fresh products and are closed by a plastic film, for example a conventional extensible food film. These trays are practical and exist in many shapes, colors and sizes, so as to adapt to the needs of the consumer.

Although useful and simple to use, these expanded polystyrene trays have some disadvantages.

In particular, polystyrene, which is the major component of these trays, is not easily recyclable and even less biodegradable. Indeed, no organized recycling path is implemented at the level of local authorities or on a larger scale; it is therefore difficult to collect for later recycling. The waste that polystyrene constitutes does not enter the traditional collection channels of sorting. Its disposal is also a real problem since it is currently most often incinerated, which inevitably leads to harmful emissions of gas and leads to energy consumption.

In addition, expanded polystyrene tends to cause gaseous emissions in the presence of heat, which could be in certain conditions harmful to humans and the environment.

In addition, these food packaging trays expanded polystyrene have the disadvantage of not always being perfectly hydrophobic, so that the moisture present in the food they contain tends to alter these trays. To overcome this problem, it is known to introduce a sealed plastic sheet between the tray and the food. This sheet nevertheless complicates the manufacture of the trays and constitutes an additional waste to be destroyed.

Therefore, the objects assigned to the invention are intended to remedy the various disadvantages listed above and to propose a new packaging material and / or insulation that is easy to form and convenient to use, while being respectful of the environment and healthy for man.

Another object of the invention is to provide a new packaging and / or insulation material which uses readily available and inexpensive ingredients. Another object of the invention is to provide a new packaging and / or insulation material that uses easy to implement ingredients. Another object of the invention is to provide a new packaging material and / or insulation which is resistant and whose mechanical properties are compatible with its use.

Another object of the invention is to provide a new packaging material and / or insulation that is waterproof.

Another object of the invention is to provide a new packaging material and / or insulation that is practical and easy to shape.

Another object of the invention is to propose a new process for manufacturing a packaging and / or insulation material which comprises simple steps that are practical and quick to implement in order to obtain an easy-to-use material. fit and convenient to use, while being environmentally friendly and healthy for humans.

Another object of the invention is to provide a new machine for manufacturing a packaging material and / or insulation which is of simple construction, convenient to use, and which allows the obtaining and the optimal shaping and fast material.

Another object of the invention is to propose a new machine for manufacturing a packaging and / or insulation material that can be implemented in a simple, automatic and practical manner.

The objects assigned to the invention are achieved using a packaging material and / or biodegradable insulation, expanded and made from at least one product of plant origin and at least one plasticizer said material being characterized in that said at least one softening agent comprises at least water and imparts shaping properties to said material by a thermoforming process.

The objects assigned to the invention are also achieved by means of a process for manufacturing a biodegradable and expanded packaging material and / or insulation, said method comprising a step of mixing at least one product of vegetable origin with at least one plasticizing agent and an expansion step, said manufacturing method being characterized in that it comprises a step of supplying water and a step of thermoforming said material.

The objects assigned to the invention are finally achieved by means of a machine for manufacturing a biodegradable and expanded packaging and / or insulation material, said process comprising an extruder designed to allow extrusion of a mixture comprising less a product of plant origin and at least one plasticizer, said manufacturing machine being characterized in that it comprises a thermoforming device designed to thermoform said material.

Other objects and advantages of the invention will appear in more detail on reading the description which follows, and with the aid of the accompanying drawings, given purely by way of illustration and without limitation, in which:

- Figure 1 illustrates, in a schematic top view, a packaging material according to the material, the method and the machine of the present invention, said material constituting in this case a food packaging tray.

- Figure 2 illustrates, in a schematic side view, the food packaging tray of Figure 1.

- Figure 3 illustrates, in a schematic front view, an output die of substantially rectangular shape of the manufacturing machine according to the present invention.

FIG. 4 illustrates, in a schematic cross-sectional view, the exit die of substantially rectangular shape of FIG. 3.

The present invention relates to a material 1 for packaging and / or insulation, that is to say a material 1 which can find an application both in the packaging, in particular in the packaging for example food, and also in the insulation, for example to thermally isolate and / or sound level a building. Preferably, the material 1 of the invention constitutes a material that can be used in the field of human nutrition, in particular a packaging tray 4 (see FIGS. 1 and 2). Alternatively, the material 1 constitutes a construction material, for example an insulating plate (not shown) designed to limit any sound and / or heat diffusion.

For the sake of clarity and conciseness, we will be interested, in the following description, preferentially to the embodiment of the material 1 in the field of packaging.

The material of the invention 1 is biodegradable, that is to say it is able to decompose naturally, in the presence of microorganisms naturally present in the environment. In other words, the material of the invention 1 is designed to destroy itself entirely by a natural way, without any negative impact for man and / or the environment.

The material 1 of the invention is further expanded, such that it comprises in particular a large number of cells, advantageously regularly distributed therein and forming a kind of foam. The material 1 of the invention has therefore undergone an expansion of its volume and its dimensions, preferably by a factor of at least 5 and in particular at least equal to 9, thanks to a phenomenon of physical expansion, in order to have a foam shape whose density is substantially lower than that of the initial unexpanded composition. Such an expanded form of the material 1 is particularly advantageous and gives said material 1, a low density and lightness optimal for its applications in insulation and / or packaging.

Preferably, the material 1 of the invention thus has an expansion index EXV at least substantially equal to 9, and substantially close to that of a conventional expanded polystyrene.

The material 1 of the invention, in particular the composition of ingredients from which said material 1 is manufactured, as described below, is therefore able to undergo and withstand an expansion, that is to say to see its dimensions increase without damage 1311628FR in terms of its integrity and / or its outfit.

In this regard, the material of the invention 1 is made from at least one product of plant origin, derived from a plant or from any tree, preferably from a cereal or a forage plant. . Advantageously, said product of vegetable origin comprises at least one flour and / or starch, for example a cereal flour and / or a starch extracted from a cereal, preferably a flour of wheat, corn and / or sorghum. Thus, the product of plant origin has a powder form, in particular of small particle size, and preferably comprises at least one wheat flour or an easily millable cereal in the form of a flour as conventionally used in animal feed. and / or human.

Said flour advantageously has a particle size of substantially between 200 and 350 μm, which facilitates the mixing of the ingredients of the material 1 as well as the subsequent treatment of the latter, for example during its expansion and shaping.

In an advantageous embodiment, the material 1 is made from at least 60% by weight of said flour. and / or said starch, for example from substantially 68% by weight of wheat flour, such a content contributing to the required mechanical properties of said material 1.

Moreover, the material 1 comprises at least one plasticizing agent, whose main function is to improve the plasticity, for example the thermoplasticity, and the flexibility of the material 1, by making it possible to obtain a homogeneous and regular mixture of the constituents of said material 1, in particular constituents of said flour of vegetable origin. Said at least one plasticizer is further intended to promote the subsequent treatment of the ingredient composition from which said material 1 is made, for example during an extrusion, expansion and / or shaping process, this list is not exhaustive.

The material 1 also preferably comprises at least 20% by weight of said at least one plasticizer, preferably at least 30% by weight of said at least one plasticizer. Said plasticizer comprises at least water and gives said material forming properties by a thermoforming process, that is to say shaping properties, in the presence of heat. Preferably, the material 1 comprises at least 10% by final weight of water, preferably substantially 11% by final weight of water. Water as plasticizer of said material 1 is preferably provided by said flour of plant origin (eg wheat), when the moisture content thereof is at least 10%, or alternatively by a external supply in the case where the moisture content of said flour is insufficient, for example less than 10% by weight of the material 1.

This plasticizing agent, in particular water, has a destructuring role of the starch molecules present in the flour and / or those added as such, so as to burst them to then promote the expansion and shaping of the material. . Indeed, the plasticizing agent of the invention is preferably inserted into the amylose and / or amylopectin chains of the starch, in order to promote the mobility of the latter and thus to make the material 1 more flexible and more flexible. easily deformable. Therefore, it advantageously plays the role of a natural expander of the material 1, in particular the initial composition at the origin of the final material 1 obtained, and avoids the use of another expanding agent.

Preferably, said at least one plasticizer also comprises at least one polyol, preferably at least one of sorbitol and / or glycerol. These substances, which are in a way adjuvants to said material 1 facilitating the treatment of the latter and which form said plasticizer, are advantageously of natural origin, for example extracted from at least one plant, and therefore contribute to the biodegradability of all of the material 1. Preferably, said at least one plasticizer is of food grade.

The precise balance of the contents of each of the plasticizers, in particular water, sorbitol and glycerol, in the material 1, gives the latter its hot forming properties, by a thermoforming process, as well as its holding after thermoforming. Preferably, the material 1 thus comprises a composition allowing its expansion, thermoforming and its maintenance in shape, without risk of softening and / or undesirable breakage. In addition, said at least one plasticizing agent B11628FR, and in particular the water has a content at least substantially equal to I o% by weight of the material 1, limits the water recovery of the material 1 and thus promotes its stability in the presence of humidité_

In addition, the material 1 advantageously comprises between substantially 1 and 3% by weight of silica, preferably substantially 1% by weight of silica, which has the main objective of providing the material 1 with mechanical properties to facilitate its further processing, particularly its extrusion, expansion and / or shaping. It is also possible that the material 1 comprises a silica content substantially equal to 2%, depending on the mechanical properties required for the material 1.

Advantageously, such a silica content of between 1 and 3% by weight of said material 1 of the invention, especially in the initial formulation of the latter, facilitates, in a non-obvious way, both the extrusion and the expansion of said material 1. Such silica content further contributes to certain mechanical properties of the material 1, especially in terms of strength, traction and stretching.

Preferably, the amount by weight of the material 1 of the plasticizer and of the silica varies according to the nature and the quantity of the product of vegetal origin used, so as to obtain a material 1 which has plasticity and cohesion properties optimal for expansion and can be further shaped.

In an advantageous embodiment, the material of the invention 1 comprises between approximately 7 and 10% by weight of proteins. This level of proteins makes it possible, surprisingly and unexpectedly, to significantly improve the properties of the material 1, more precisely of the composition from which said material 1 is obtained, in particular its resistance properties to an extrusion process. expansion and / or shaping.

Preferably, the material 1 has a substantially flattened shape obtained by means of a flat extrusion process. In other words, the material 1 is advantageously of substantially flat shape, and extends mainly in a substantially horizontal extension plane, in particular after being extruded and expanded. The material 1 by its particular composition is expandable in a substantially flat form, preferably in the form of a plate having a substantially uniform thickness. The material 1 preferably has the shape of a substantially parallelepiped expanded volume, this particularly surprisingly and unexpectedly for a biodegradable material based on flour of vegetable origin.

In addition, the material 1 of the invention is preferably covered at least in part by at least one fatty compound designed to give it hydrophobicity properties, preferably by a linseed oil. Advantageously, the material 1 therefore comprises a layer of a fatty substance, of the drying oil type, applied to the surface 2 of said material 1 (see FIGS. 1 and 2), in order to render it substantially impermeable to fluids, in particular to liquids and especially to water. Preferably, the oil covers the inner face 3 of the material 1 when the latter is a food tray 4 as illustrated in Figures 1 and 2, so that the moisture may be present in food deposited on the face 3 inside said tray 4 does not alter the integrity of said tray 4.

The fatty substance deposited on said material 1 of the invention thus advantageously avoids any degradation of said material 1 in the presence of a fluid, for example in the presence of moisture which is likely to interact with the hydrophilic starch molecules of the material 1 The fatty substance therefore preferably avoids any penetration of a fluid into the material 1, so as to preserve the integrity and the strength of said material 1.

It is alternatively perfectly conceivable, without departing from the scope of the present invention, for the material 1 to be rendered hydrophobic by means of a component other than a fatty substance, in particular using an applied synthetic polymer. on said material 1 or integrated with its constituents. It is for example a biodegradable synthetic polymer chosen from the group formed by poly (vinyl alcohol), poly (ethylene-co-vinyl alcohol), poly (caprolactone) or acetate of cellulose, this list is not exhaustive.

The material 1 of the invention may also comprise other minor ingredients, for example manufacturing aids and / or additives, such as dyes and / or texturizers, which are advantageously biodegradable. The material 1 of the invention is furthermore capable of being shaped by means of a heat source, by a thermoforming process, that is to say that it is suitable for shaping or a molding in the presence of heat, in order to be shaped for its subsequent use, especially thanks to the presence of the aforementioned plasticizers.

Thus, as illustrated in FIGS. 1 and 2, the material 1 is thermoformed in the form of a tray 4 which preferably comprises a bottom 5 and an edge 6 that is substantially curved in order to retain the product deposited on the inner face 3.

Advantageously, the material 1, in the case of said tray 4 or a packaging material, comprises a thickness between substantially 0.05 and 5 cm, preferably between substantially 0.5 and 2 cm. The packaging material 1 furthermore has, on the one hand, a length of between approximately 1 and 40 cm, preferably between approximately 10 and 30 cm, advantageously equal to approximately 19.5 cm, and on the other hand a width 11 of between 11 and 30 cm. between substantially 1 and 20 cm, advantageously between substantially 5 and 10 cm, and even more advantageously substantially equal to 6 cm. Preferably, the height 12 of said material 1 when it is thermoformed in the form of a packaging, for example of tray type 4, is between substantially 0.2 and 5 cm, preferably between 1 and 3 cm, and more particularly substantially equal to 1.5 cm.

Alternatively, in the case where the material 1 of the invention constitutes an insulating material, it comprises dimensions substantially greater than those of a packaging material. In particular, in this embodiment, the material 1 advantageously has a thickness of between substantially 1 and 10 cm, a length 10 of between substantially 1 and 5 m, a width 11 between substantially 5 and 30 cm and a height 12 included between substantially 2 and 10 cm.

Thus, the composition of the material 1 of the invention advantageously guarantees the thermoforming of the material 1 and further ensures effective holding of said thermoformed material 1, in addition to allowing, as specified above, its optimal expansion and / or extrusion , prior to the thermoforming process. In other words, the material 1, in particular by virtue of its intrinsic characteristics related to its composition, and in particular its level of proteins, silica, plasticizer and vegetable flour, has excellent strength and is thermoformed, as well as an optimal resistance and water recovery after shaping.

In addition, the material 1 is adapted to be placed in contact with at least one food product intended for human and / or animal consumption.

In a particularly preferred embodiment, the material 1 is also a thermoformed food package, in which is advantageously stored, packaged or packaged a food product, for example a fresh product such as meat.

Thus, the composition of said material 1 of the invention has intrinsic properties allowing it to undergo different treatments under particularly difficult temperature and pressure conditions, in particular flat extrusion and expansion, and making it possible to obtain properties of the material 1, especially in terms of thermoforming. This material 1 also has excellent strength in substantially flat form expanded after extrusion and then in a shaped form, for example of the tray type 4 with curved edges 6, after a thermoforming process.

The present invention also relates to a method of manufacturing a packaging material and / or insulation 1, biodegradable and expanded, preferably in accordance with the material 1 described above. It is therefore advantageously a method of manufacturing a packaging or packaging, for example in the food industry as a tray 4 of food packaging, or a soundproofing and / or thermal insulation plate usable in the field of construction, for example for the insulation of a building.

The process of the invention comprises a step of mixing at least one product of plant origin with at least one plasticizer, during which the ingredients necessary for obtaining the material 1 of the invention are mixed together. . Preferably, the mixing step comprises an operation of preparing a mixture, which corresponds to the composition from which said material 1 is obtained, from at least 60% by weight of a wheat flour and at least 20% by weight of at least one plasticizer. Said at least one plasticizer is advantageously substantially identical to the one mentioned above, that is to say that it comprises at least water, which actively contributes to the properties of said material, in particular for its extrusion, expansion and forming .

It is also possible that the water-supplying step is substantially identical and / or simultaneous with the step of mixing the ingredients, in the case where the moisture content of the latter is sufficiently high, that is to say say preferably at least equal to 10% by weight of said mixture, so as to constitute alone a water supply to obtain the desired properties of the material 1.

Indeed, said manufacturing method of the invention comprises a step of supplying water into the mixture comprising at least one vegetable meal, of small particle size. Preferably, the water-supplying step consists of adding more than 10% of water to the mixture, preferably about 110% of water, in a mixture comprising about 68% of cereal flour, preferably of wheat flour. The mixing step also comprises an operation for adding one or more plasticizing agent (s), other than water, preferably glycerol and sorbitol, in substantially equal proportions by weight of the mixture. at about 10% and about 8% respectively.

The method also comprises a flat extrusion step of said material 1, such that said material 1 has a substantially flattened shape. Said flat extrusion step is preferably carried out using a flat die 23 detailed below, in order to obtain a biodegradable material 1 in substantially flat expanded form, preferably of substantially parallelepiped shape.

Preferably, the extrusion step comprises first of all a kneading operation of said mixture during which a double extrusion screw (not shown) is rotated, so as to ensure a homogeneous mixture of the constituent ingredients. of said material 1. The extrusion double screw is advantageously rotated at a speed of rotation of between substantially 300 and 900 rpm, preferably equal to 600 rpm, for example at a speed of 598 revolutions per minute. minute. This speed of rotation of the extrusion double screw is perfectly adapted to obtain the optimum properties of the material 1 of the invention, in particular in terms of flat extrusion, expansion and subsequent shaping. Indeed, the speed of the screw at around 600 revolutions per minute guarantees an effective destructuring of the starch granules and a perfect insertion of the plasticizers into the amylose and amylopectin chains, so that the material 1 is able to be expanded, extruded and shaped.

In addition, the extrusion step comprises an operation of heating said mixture, during which the temperature of said mixture is gradually increased to at least 100 ° C., preferably to substantially 120 ° C. or even 140 ° C. , depending for example on the nature of the flour used. During this heating step, said mixture preferably based on wheat flour, water, sorbitol and glycerol, is heated to less than 100 ° C., progressively in different zones of said extruder 20, preferably in at least ten heating zones of the latter.

In a particularly preferred embodiment, the heating operation, carried out simultaneously with the kneading operation in said extruder 21, thus comprises a gradual increase in temperature of the mixture to at least 100 ° C., preferably up to at least 120 ° C, then a descent of the temperature close to 100 ° C at the end of the extruder 21 before the exit of the material 1. This final lowering of the temperature in the extruder 21 improves the characteristics of the material 1 .

The extrusion step then comprises an operation for passing material 1 through a die 23, during which said material 1 is preferably extruded through a die 23 of substantially flat shape and of substantially rectangular cross section (see FIGS. and 4), so as to obtain an extruded material in a substantially flattened shape and able to expand in a substantially parallelepipedal shape.

Said method also comprises an expansion step, which is preferably carried out after the aforementioned extrusion step. The very nature of the material 1, in particular its composition, in particular in terms of the quantity and nature of plasticizer combined with a vegetable meal, causes its natural expansion in a substantially flat expanded form, for example in the form of a substantially parallelepipedic volume. at the outlet of the extruder 21.

Preferably, the process of the invention comprises, after the extrusion step, a step of applying a fatty substance to at least a portion of the surface of said material, in order to render it substantially hydrophobic. This step is advantageously carried out after the above-mentioned extrusion and natural expansion step, and before thermoforming the material 1. It is however possible to apply one or more drying oils to the material 1 after it has been formed. . Alternatively, this step of applying a fatty substance is carried out after thermoforming said material 1.

The method of the invention further comprises a step of thermoforming said material, during which the material 1 is formed in the presence of heat, preferably with the aid of a heating press for example a thermoformer (not shown). The thermoforming step, advantageously carried out after the step of expanding the material 1, ensures the production of an expanded material 1, in particular after an extrusion step, formed as a function of its subsequent use and of which the outfit is efficient enough for the desired use.

The thermoforming step comprises for example a molding operation using a mold (not shown) heated at least in part, during which said mold is embedded in the material 1 extruded and expanded, so that imparting to said material 1 its shape. Thus, depending on the material 1 and the shape required for the latter, it is conceivable that the thermoforming step comprises one or more molding operation (s) using one or more mold (s), as well as at least one heating operation of said mold.

The method of the invention also advantageously comprises a step of conveying said material 1, during which said extruded and expanded material 1 is displaced, for example on a conventional conveyor (not shown) and brought to a zone B11628FR thermoforming at which it undergoes said thermoforming, for example with the aid of said thermoformer.

In a particularly preferred embodiment, the manufacturing process constitutes a method of manufacturing a thermoformed food package, for example a food tray 4, curved at its edges 6.

Alternatively, however, it is perfectly conceivable, without departing from the scope of the present invention, the method of the invention is a method of manufacturing an insulation plate, for example thermal and / or phonic, designed to isolate a building.

The method of the invention thus makes it possible, by means of simple and rapid steps to implement, to obtain a packaging and / or insulation material 1 which is completely biodegradable, expanded and able to be thermoformed, from natural resources and readily available, including from cereal flour and water.

Finally, the present invention relates to a machine 20 for manufacturing a biodegradable and expanded packaging and / or insulation material 1, said machine 20 being preferably designed to manufacture the packaging and / or insulation material 1 described above and to implement the steps of the method of manufacturing said material 1 according to the foregoing.

The machine 20 is advantageously intended for the manufacture of a packaging material 1, for example in the food industry. Preferably, the machine 20 preferably constitutes a machine 20 for manufacturing a material 1 suitable for being put in contact with at least one food product intended for human and / or animal consumption. For example, this machine 20 constitutes a machine for manufacturing packaging trays 4 (see FIGS. 1 and 2) intended to receive a product for human and / or animal consumption, for example meat. Alternatively and according to another advantageous embodiment, the machine 20 constitutes a machine 20 for manufacturing an insulating material 1, in particular B11628FR phonic and / or thermal, which can be used in the field of construction, for example in the form of a printing plate. insulation (not shown) for buildings.

The machine 20 comprises an extruder 21, partly illustrated in Figures 3 and 4, designed to allow extrusion of a mixture comprising at least one product of plant origin and at least one plasticizer. Preferably, and as explained in the description above, the mixture, forming the composition from which said material 1 is made, comprises at least one cereal flour and / or a starch, preferably a wheat flour, to which at least water is added as a plasticizer, a destructuring agent for the starch molecules and the foaming agent. The mixture also comprises, before passing into the extruder 21, at least one other plasticizer, for example sorbitol and / or glycerol. The precise mixture of the invention guarantees the passage of the material 1 in the machine 20.

Preferably, the manufacturing machine 20, in particular the extruder 21, comprises a rotating double screw (not shown) designed to mix said mixture, while also ensuring its transport and routing along said extruder 21, and having a rotational speed between substantially 300 and 900 revolutions per minute, preferably equal to substantially 600 revolutions per minute. Surprisingly and unexpectedly, a rotational speed of the double rotary screw equal to substantially 600 rpm, for example equal to 598 revolutions per minute, makes it possible to obtain a homogeneous mixture and an effective destructuration of the starch molecules contained therein. in the mixture and thus ensures optimum extrusion of the material 1 through the outlet die 23, to obtain a material 1 expanded flat and easily deformable later. As mentioned above, it has been shown in particular that a rotational speed of about 600 revolutions per minute of the double screw of the machine 20 ensures the formation of a material 1 having optimal properties of extrusion, expansion and forming, especially in the presence of heat during forming, in connection with the composition of said material 1.

In an advantageous embodiment, the machine 20, in particular the extruder 21, comprises an exit die 23 of substantially flat shape, such that said extruded material 1 has a substantially flattened shape. In a preferred manner, the exit die 23 of the extruder 21 has a substantially parallelepipedal shape with, for example, a substantially rectangular section, as illustrated in FIGS. 3 and 4, so that the material 1 forced through said die The outlet 23 is substantially flat in shape and is also preferably expanded in a predominantly flattened form, for example in a substantially parallelepipedal shape or a pavement. Preferably, the material 1 is thus forcefully introduced at an inlet opening 26 of the outlet die 23, and forced therethrough, to an outlet opening 22, said outlet die 23 having a substantially rectangular cross section with a width 24 between substantially 0.1 and 10 mm, more particularly between substantially 0.5 and 5 mm, and preferably equal to substantially 1 mm. The outlet die 23 further comprises a length of between substantially 1 and 10 cm, more particularly between 2 and 5 cm, preferably equal to substantially 4 cm.

Alternatively, it is also conceivable without departing from the scope of the present invention that the exit die 23 comprises a different shape, for example with another section of geometric or non-geometrical shape, which makes it possible to obtain an expanded material 1 of substantially flattened shape. .

The manufacturing machine 20 also comprises a thermoforming device (not shown), for example a thermoforming machine, designed to thermoform said material 1, preferably after its exit from the extruder 21. The material 1 extruded in the extruder 21 and expanded in a substantially flat shape is therefore placed in the thermoforming device, so as to form it, that is to say the shape or impart a particular form, in the presence of heat and pressure.

The use of the thermoformer makes it possible to form thermoplastic materials, that is to say which have properties compatible with stretching and / or pressure, which is the case of the material 1 of the invention which has properties thermoplastics in particular to allow it to be extended, stretched and / or lengthened. In particular, the thermoforming machine used in the present invention comprises at least one mold and / or a tray (not shown), which can be heated at least in part and designed to be brought into contact with extruded and expanded material 1, B11628FR with a view to to impart to him a particular form.

In particular, the thermoforming machine uses a temperature substantially between 20 and 50 ° C, sometimes up to 100 ° C and a pressure of between substantially 1 and 2 bars, for the optimal thermoforming of the material 1 and its resistance in thermoformed form , later during its use.

In a particularly preferred embodiment, said machine 20 comprises a conveyor (not shown), for example a conventional conveyor in the form of a moving carpet, designed to allow said extruded and expanded material 1 to be fed out of the extruder. 21 to said thermoformer.

Thus, the machine of the invention leads to a biodegradable material, extruded and expanded flat which can be used in many applications. It makes it possible in particular to obtain a material solely from agro-resources, whose precise composition makes the material suitable for extrusion through the flat die 23 of the machine 20 and then to thermoforming.

In the following description, we will attempt to describe some embodiments of the material 1 of the invention, purely illustrative and not limiting.

EXAMPLES OF REALIZATION

A first example (F1) of the material 1 of the invention, in the case of a food packaging tray, as mentioned above, has the following composition expressed as a percentage (%) by weight of the composition: Component% by weight of the material Wheat flour 68 Water 11 Glycerol 10 Sorbitol 8 Silica 3 B11628EN This particular F1 composition of the material 1 of the invention, before its extrusion, guarantees optimal extrusion, expansion and thermoforming of the material 1, in particular under the aforementioned conditions use of the machine 20 and implementation of the manufacturing method of the invention.

A second example of material 1, the following composition F2, expressed as a percentage (%) by weight of the composition, was the subject of a second experiment: Component% by weight of the material Wheat flour 88.6 Sorbitol In this experiment, the aforementioned F2 composition was tested in a rotary twin-screw extruder according to the present invention to determine what was the best behavior of the material according to the evolution of the composition. temperature in twelve (12) extruder heating zones defined by references Z1 to Z12 in the table below.

The table below shows the parameters used in particular a screw speed of 598 revolutions per minute (see column 2), the stop pressure expressed in bar, the temperature in each of the twelve zones Z1 to z12 expressed in degrees. Celsius CC), the powder flow rate (in mL per hour), the water flow rate (in mL per hour) and the percentage of water added (% by weight of the composition). Screw Z1 Z2 Z3 Z4 Z5 Z6 Z7 Z8 Z9 Z10 Z11 Z12 Flow rate Flow rate% water rpm / ° Stopper powder water added torque bar 1 598 58 27 119 20 40 87 115 114 118 111 111 121 131 141 141 30.00 2.21 6.9 2 598 58 28 121 20 40 89 113 111 113 110 110 120 130 140 140 30.00 2.79 8.5 3 598 42 19 120 20 - 91 103 106 - 109 110 _ - 128 139 138 30,00 3,48 10,4 39 105 119 B 11628FR The gradual rise in temperature within the extruder between zones Z1 and Z12 makes it possible to obtain a material 1 which has optimum characteristics for extrusion, expansion and thermoforming, especially when the speed of the screw is 598 revolutions per minute.

A third example of formulation F3 comprising only wheat flour and glycerol, according to the following composition F3 expressed in percentage by weight of material 1, was the subject of another test on the same rotary twin screw extruder that that of the second example: F3 Wheat flour 95.0% Glycerol 5.0% The parameters tested are the same as those of the second example and listed in the following table:% Z1 Z2 Z2 Z3 Z4 Z5 Z6 Z7 Z8 Z9 Z10 Z11 Z12 flow rate% bucket rpm torque Thrust buffer powder water added bar 1 598 53 25 98 20 39 100 101 101 115 118 119 120 129 105 111 30.00 4.81 13.8 2 351 73 42 97 20 39 105 100 99 107 110 114 115 119 106 110 30.00 3.50 10.4 3 351 70 41 102 20 41 103 100 100 94 105 111 112 117 106 119 30.00 3.48 10.4 4 598 54 31 103 20 38 99 100 100 100 110 115 117 122 102 119 30.00 4.12 12.1 5 351 66 39 103 20 40 100 100 100 93 104 110 111 114 99 119 30.00 4.10 12.0 The F3 formulation made the subject of an increase in his temperature in Z1 to Z10 of the extruder up to about 120 ° C and then a decrease in temperature in the last two zones Z11 and Z12 to about 105-110 ° C. Such a decrease in the heating temperature of the mixture at the end of the extruder has, unexpectedly, made it possible to optimize the mechanical properties of the material F3.

It has furthermore been shown in this example that the rotation speed of 598 revolutions per minute guarantees the obtaining of a material having the best mechanical properties, in particular with a view to its extrusion, expansion and thermoforming, in comparison with speeds lower (eg 351 rpm). These examples of formulations, based on simple and easily available ingredients, guarantee the production of a biodegradable material 1, completely natural and obtained from agro-resources and natural compounds, which can be easily extruded flat, expanded and thermoformed by conventional extrusion and thermoforming processes.

The packaging and / or insulating material 1 of the invention, as well as the machine and the method of manufacturing this material 1, are therefore particularly suitable in the field of packaging, in particular for the manufacture of biodegradable packaging. , effective and safe for humans, and secondly in the field of insulation, in particular to obtain biodegradable insulating plates and effective in terms of sound insulation and / or thermal. B 11828FR

Claims (9)

CLAIMS1 - Packaging and / or insulation material (1) biodegradable, expanded and made from at least one product of plant origin and at least one plasticizer, said material (1) being characterized in that said at least one plasticizer comprises at least water and gives said material (1) shaping properties by a thermoforming process. 2 - Packaging and / or insulation material (1) according to claim 1 characterized in that said product of plant origin comprises at least one flour and / or a starch, preferably at least one wheat flour. 3 - Packaging material and / or insulation (1) according to claim 2 characterized in that it is made from at least 60% by weight of said flour and / or said starch. 4- packaging material and / or insulation (1) according to claim 2 or 3 characterized in that said flour has a particle size between substantially 200 and 350 pm. 5 - Packaging and / or insulation material (1) according to one of claims 1 to 4 characterized in that it comprises at least 20% by weight of said at least one plasticizer, preferably at least 30% by weight. weight of said at least one plasticizer. 6 - Packaging and / or insulation material (1) according to one of claims 1 to 5 characterized in that said at least one plasticizer comprises at least sorbitol and / or glycerol. 7 - Packaging and / or insulation material (1) according to one of claims 1 to 6 characterized in that it comprises at least 10% by final weight of water, preferably substantially 11% by final weight of 'water. B11628FR 8 - Packaging and / or insulation material (1) according to one of claims 1 to 7 characterized in that it comprises between substantially 1 and 3% by weight of silica, preferably substantially 1% by weight of silica . 9 - packaging material and / or insulation (1) according to one of claims 1 to 8 characterized in that it comprises between 7 and 10% by weight of protein. -I conditioning and / or isolation material (1) according to one of claims 1 to 9 characterized in that it is covered at least in part by at least one fatty compound designed to confer properties hydrophobicity, 10 preferably by a linseed oil. 11-conditioning and / or insulation material (1) according to one of claims 1 to 10 characterized in that it is adapted to be brought into contact with at least one food product intended for human consumption and / or animal. 12-conditioning and / or insulation material (1) according to one of claims 1 to 11 characterized in that it has a substantially flattened shape obtained by means of a flat extrusion process. 13-conditioning and / or insulation material (1) according to one of claims 1 to 12 characterized in that it constitutes a thermoformed food packaging. 14 -Process of manufacturing a packaging material and / or insulation (1) biodegradable and expanded, said method comprising a step of mixing at least one product of plant origin with at least one plasticizer and a step of expansion, said manufacturing method being characterized in that it comprises a step of supplying water and a step of thermoforming said material (1). Production method according to claim 14, characterized in that the mixing step comprises an operation for preparing a mixture from at least 60% by weight of a wheat flour and at least 20% by weight of at least one plasticizer. B11628EN 16 -Procédé manufacturing according to claim 14 or 15 characterized in that it comprises a flat extrusion step of said material (1), such that said material (1) has a substantially flattened shape. 17 -Procédé method according to claim 16 characterized in that the extrusion step comprises a heating operation of said mixture, during which the temperature of said mixture is gradually increased to at least 100 ° C. 18 -Procédé manufacturing according to claim 16 or 17 characterized in that the extrusion step comprises a kneading operation of said mixture in which a double extrusion screw is rotated. 19-manufacturing method according to claim 18 characterized in that the double extrusion screw is rotated at a rotation speed between substantially 300 and 900 rpm, preferably equal to substantially 600 rpm. Manufacturing method according to one of claims 16 to 19, characterized in that it comprises, after the extrusion step, a step of applying a fatty substance to at least a part of the surface (2). ) of said material (1), to make it substantially hydrophobic. 21 -Procédé method according to one of claims 14 to 20 characterized in that it constitutes a method of manufacturing a thermoformed food packaging (4). 22 -Machine (20) for manufacturing a biodegradable and expanded insulation and / or insulation packaging material (1), said machine (20) comprising an extruder (21) designed to allow extrusion of a mixture comprising at least one product of plant origin and at least one plasticizing agent, said manufacturing machine (20) being characterized in that it comprises a thermoforming device designed for thermoforming said material (1). B11628FR23 -Machine manufacturing (20) according to claim 22 characterized in that it comprises an output die (23) of substantially flat shape, such that said material (1) extruded has a substantially flattened expanded form. 24 -Machine manufacturing (20) according to claim 22 or 23 characterized in that it comprises a rotating double screw designed to mix said mixture and having a rotation speed of between substantially 300 and 900 revolutions per minute, preferably equal to substantially 600 rpm. -Machine manufacturing (20) according to one of claims 22 to 24 characterized in that it constitutes a machine for manufacturing a material (1) adapted to be brought into contact with at least one food product for the human and / or animal consumption. B 11628FR