FR2957609A1 - Fabricating elastic nonwoven fabric that is useful to manufacture diaper, by forming web of melt blown fibers from extrudable mixture including thermoplastic elastomer on receiving support, and expelling fabric to scrolling direction - Google Patents

Abstract

The process comprises forming a web of melt blown fibers (2) from an extrudable mixture including a thermoplastic elastomer on a receiving support (7) using an extrusion unit and a blowing unit (1, 3, 4, 5) including a blown extrusion die, and expelling a first nonwoven fabric according to a scrolling direction by the extrusion die so that the melt blown fibers are blown on first side of the first nonwoven fabric. The blown extrusion die comprises rows of spinning orifices (8). The process comprises forming a web of melt blown fibers (2) from an extrudable mixture including a thermoplastic elastomer on a receiving support (7) using an extrusion unit and a blowing unit (1, 3, 4, 5) including a blown extrusion die, and expelling a first nonwoven fabric according to a scrolling direction by the extrusion die so that the melt blown fibers are blown on first side of the first nonwoven fabric. The blown extrusion die comprises rows of spinning orifices (8), where the blowing is carried out according to a direction of blow through blowing orifices surrounding the spinning orifices. A direction of blowing is perpendicular to the direction of scrolling. The web of melt blow fibers are blown on the side of first and second nonwoven fabrics up to a deviation point and then the first and second nonwoven fabrics are diverted to the scrolling direction, and are interposed between the sides of the nonwoven fabric. The melt blown fibers are aspirated by an air flow suction through the first nonwoven fabric and optionally through the second nonwoven fabric so as to facilitate the deposition of the melt blown fibers on the first side of the first nonwoven fabric. The receiving support is arranged at a determined distance of less than 1 m from the spinning orifices. The first and second nonwoven fabrics are carded web fibers. An independent claim is included for a device for fabricating an elastic nonwoven fabric.

Description

METHOD FOR MANUFACTURING AN ELASTIC NONTISSE AND DEVICE FOR IMPLEMENTING SAID METHOD

The present invention relates to the technical field of elastic nonwoven manufacturing processes, as well as that of devices for carrying out such methods. Elastic nonwovens obtained by superimposing a web of nonuniform carded fibers or spunbond with a web of blown-melted fibers (also called meltblown voile in the present text) elastic from a thermoplastic elastomer are known. The web of carded fibers or non-elastic spunbond is necessary in order to provide a pleasant touch and to prevent the user's skin from coming into contact with the web of elastic meltblown fibers having a tack, that is to say to say a sticky touch important because of the elastic material used. This in particular when the elastic nonwoven obtained is intended to form the comfort band diapers that can come into contact with the skin of babies. The veil of carded fibers or spunbond also has the function of mechanically reinforcing the elastic meltblown veil, in particular improving its resistance to tearing.

The non-elastic web of carded fibers or spunbond is assembled to the meltblown elastic web either directly during the manufacture of said meltblown web, the latter being deposited still in the softened state at the extrusion-blow die exit directly on the carded web or spunbond, or by passing the assembly formed on a heated calender.

The extrusion blow molding technique used comprises an extrusion blow die having a row of spinning orifices. In this case, the blowing means are arranged on either side of said extrusion blow die, along the upper and lower edges or along the lateral edges of said row of spinning orifices, so as to generate two flows. converging air substantially opposite the spinning orifices. This technique is generally implemented on extrusion blow molding lines marketed by Reifenhauser. The web of carded fibers or spunbond being inelastic limits the elastic properties of the elastic meltbown web since all the points of connection between the non-elastic web and the elastic meltblown web form stopping zones of the resilience of the elastic meltblown web. Thus, in order to improve the elastic properties of the assembly resulting from the superposition of the web of carded or spunbond fibers with the meltblown web, said assembly is cold-calendered between two grooved rolls so as to stretch at least in a given direction said assembly and that it is elastic at least in said given direction. The assembly obtained then has longitudinal folds, generally transverse to the elastic direction conferred. This stretching operation, generally called "Ring-Roll", decreases the mechanical properties of said assembly, in particular its resistance to tearing and considerably modifies its appearance since the latter has many fold lines. Such a technique is also known from US 4,517,714 and US 4,384,741. When a second web of carded fibers or spunbond is superimposed along the face of the elastic meltblown web not covered with the first web of carded fibers or spunbond, said second web is necessarily assembled by hot calendering of the assembly formed of the three superimposed layers. Indeed, the second non-elastic veil is deposited on the elastic melblown veil after the deposition of said elastic meltblown veil on the first veil, said elastic meltblown veil thus has time to cool and adheres very little to the second veil. It is therefore necessary to carry out hot calendering in order to improve the connection between the three sheets, and to avoid any subsequent delamination. This hot calendering step has the disadvantage of freezing the different layers of nonwoven between them, reduce the elongation properties and stiffen said layers thus changing their feel.

An object of the present invention is to improve the method of manufacturing an elastic nonwoven fabric, in particular productivity and energy consumption. Another object of the present invention is to provide an elastic nonwoven having a tacky or tacked appearance, or even eliminated. The present invention also aims to improve the elastic properties of an elastic nonwoven while preserving its mechanical properties, including its tear resistance. The present invention overcomes the aforementioned problems in that it relates, in a first aspect, to a method of manufacturing an elastic nonwoven comprising a step of forming a web of molten-blown fibers (or meltblown veil). ) on a receiving support, from an extrudable mixture comprising at least one thermoplastic elastomer, using extrusion means and blowing means comprising an extrusion-blow die. Typically, said extrusion blow-molding die comprising several rows of spinning orifices, the blowing is carried out, preferably in parallel flow and in the same direction, in a so-called blowing direction, through blow holes surrounding each said spinning orifices.

The term "elastomer" according to the invention is understood to mean any polymer or copolymer having elastic properties equivalent to those of natural rubber. An elastomer returns rapidly and approximately to its original shape and size after stress has ceased, and even repeatedly, stress having produced a given large deformation.

Thus, the most remarkable property of elastomers is the elasticity or the ability to elongate without breaking very high (up to 1000%). Only elastomers that can be extruded can be used in the context of the present invention. Thermoplastic and olefinic elastomers are preferred in the context of the present invention.

EP 1.023.379 B1 describes a process for obtaining a thermoplastic elastomer that can be used in the context of the present invention.

The term "elastic" according to the present invention refers to a fiber, a filament, or a nonwoven, to any material which under the application of a given force in a given direction, stretches from a rest length to a given length in said direction, said given length being at least 150% or one and a half times said length at rest. Said material is then able to cover at least 50% of its elongation when it ceases to apply said force. The term non-elastic means any material that does not meet this definition. In the present application, the term "non-woven fabric" or "veil" refers to a web having a structure of individual fibers or filaments which are intermingled in an unidentifiable manner, in contrast to, for example, a knitted fabric or a fabric. tissue. Nonwovens or webs can be formed from many techniques, such as for example: extrusion blow molding processes (known in the technical field as meltblown processes), molten-bond processes (known in the field technical under the term spunbonding processes), and the carded processes (known in the technical field under the term carded processes). The weight of a nonwoven is measured in grams per square meter (g / m2). The fineness of the fibers and / or filaments is generally measured in deniers or micrometers.

The term nonwoven according to the invention thus denotes a carded fleece, possibly bonded, a meltblown sail, a spunbond sail or a spunlace sail or a combination of these sails. The term "spunlace" is understood to mean any web comprising continuously spun filaments and / or carded fibers, which web is mechanically bonded by water jet, causing said filaments and / or fibers to become entangled. The term "meltblown veil" is understood to mean any veil comprising melted-blown fibers, that is fibers formed by extrusion of a thermoplastic material, generally having a low viscosity, melted and pushed through a plurality of layers. spinning orifices, usually circular. The fibers, continuous (in this case it is filaments) or not, are directed and oriented by a flow of air.

It is understood by receiving support according to the invention, any support adapted to receive the elastic nonwoven according to the invention, and possibly to route it. Said support may be conveying means comprising a conveyor belt or another nonwoven disposed on said conveying means. Preferably, the extruded-blown fibers and filaments have a diameter in the range [2 μm; 50 μm], in particular in the following interval [5 μm; 25 μm], preferably in the following range [10 μm; 25 μm].

The extrusion blow molding die according to the invention, comprising several rows of spinning orifices and individual blowing means by blowing orifice, is known in the technical field, in particular from US 4,380,570. Surprisingly, for a given MFI (Melt Flow Index) elastomer implemented according to the method of the invention, the elastic nonwoven obtained has improved tear resistance and a less tacky or sticky feel compared to nonwoven obtained from said given MFI elastomer and manufactured by an extrusion blow molding technique having two convergent air streams and disposed on either side of a row of spinning orifices. The elastic nonwoven according to the invention is also brighter (or less matte). A non-exhaustive explanation would be that each extruded elastomeric thermoplastic filament being blown individually, the filaments can not stick together at the extrusion blow-molding outlet, so there is no clumping or clumping. hardened areas in the meltblown veil. The meltblown web according to the invention has improved elasticity for a given MFI extrudable elastomer. The elastic meltblown veil obtained also has, compared to a elastic meltblown veil of the state of the art having a weight / m2 substantially identical, more inflating.

In addition, the blowing speed being very high, preferably close to the speed of sound, less heat is required to extrude a given MFI polymer (Melt Flow Index), so that the extrudable mixture is less degraded by heat. and / or possibly the residence time in the extruder, the meltblown veil obtained has improved mechanical properties, in particular a better resistance to tearing.

It has also been observed that the extrusion blow molding means according to the invention make it possible to extrude thermoplastic elastomers having a lower MFI than those authorized with the extrusion blow molding technique using two convergent streams. However, the more the thermoplastic elastomers have low MFI (Melt Flow Index) values, the better their elastic properties. In a variant, in which the elastic nonwoven is formed by assembling a nonwoven and an elastic meltblown veil, the method comprises conveying a first nonwoven already constituted in a running direction under the extrusion blow-molding die ensures that the fleece of molten-blown fibers (or meltblown fleece) is blown onto the first face of said first nonwoven acting as reception support. Depending on the final application of the elastic meltblown veil, when the latter comes into contact with the skin, particularly with sensitive skin, it may be necessary to have a first non-woven soft touch to protect the skin of the skin. user of the contact with the meltblown web comprising a thermoplastic elastomer. Advantageously, it has been noted that the nonwoven obtained is elastic as defined in the sense of the present invention and has good elastic properties in all directions. It is not necessary to carry out a mechanical stretching operation, for example of the "Ring-Roll" type, in order to impart elastic properties in at least one direction to the nonwoven obtained by the superposition of said meltblown veil and the first nonwoven. By adjusting the angle between the blow and travel directions, it is possible to adjust the penetration or non-penetration of the melted-blown fibers into the thickness of the first nonwoven in order to adjust the bond strength between the two. layers. Preferably the blowing direction is perpendicular to the direction of travel. In a subvariant in which the elastic nonwoven is formed by assembling an elastic meltblown veil interposed between two nonwovens, the method comprises conveying the first and second non-woven fabrics already formed, and conveying the first and second nonwovens is carried out so as to convey the first nonwoven to the second nonwoven, the web of molten-blown fibers being blown onto the first face of both the first and second nonwovens. second nonwovens, to the level of a deflection point and then deflect the first and second nonwovens according to said direction of travel so that the first face of the first nonwoven is with respect to the first face of the second non-woven, the web of elastic melted fibers being interposed between the two said first faces, acting as reception support. According to the final application of the elastic meltblown veil, when the latter comes into contact with the skin, in particular with sensitive skin, it may be necessary to have a first nonwoven and second nonwoven on the two opposite faces of said meltblown veil protecting the user's skin from contact with the meltblown veil comprising a thermoplastic elastomer. Said first and second nonwovens being preferably selected so as to be soft to the touch. The meltblown veil comes into contact, again in the softened state, with each of the first faces of the first and second nonwovens, which are deflected with respect to each other. This advantageously makes it possible to obtain a bond between the first and second nonwovens via the meltblown veil and to overcome a subsequent heat-calendering operation of the three superposed layers, the hot calendering operation consisting in creating inter-layer bonding points by melting clusters of fibers and / or filaments and thereby decreasing the elastic properties of the finished elastic nonwoven fabric. The finished elastic nonwoven, resulting from the superimposition of at least three layers, thus has better mechanical performance, including improved tear strength as well as more swelling and improved elastic properties. Finally, the productivity of the finished nonwoven fabric is improved and the energy consumption reduced since a calendering step is eliminated.

Preferably, the first nonwoven and the second nonwoven comprise fibers and / or filaments chosen from the following polymers, alone or as a mixture: polyethylene terephthalate, polyamide 6-6, 4-6 or 12, polypropylene, polyethylene , viscose. Preferably, the fibers and / or filaments have a titration in the range of [1.0 denier; 8 denier], more preferably in the following interval [1.5 denier; 3.5 deniers]. In a variant, the blowing direction is substantially parallel to the direction of travel. In a variant, the extrusion die is disposed facing said point of deflection. Advantageously, the melted-blown fibers are deposited both on the first faces of the first and second nonwovens and between them when they meet at the point of deflection. This arrangement makes it possible to improve the adhesion between said first and second nonwovens since fibers still in the softened state are blown directly between them. In a variant, said melted-blown fibers are sucked by a suction air flow passing through the first nonwoven, and optionally the second nonwoven, so as to facilitate the deposition of said melted-blown fibers on the first face of the first nonwoven, and optionally the first face of the second nonwoven. This arrangement is complementary to the flow of air blowing through the blow holes around each extruded filament, and improves control of the direction in which the melted-blown fibers are directed to the first face of the first nonwoven, and optionally the second face of the second nonwoven.

In a variant, the reception support is arranged at a determined distance (D), spinning orifices, preferably less than 2 m, preferably less than 1 m. In the variant in which the first and second nonwovens act as reception supports for the elastic meltblown web, preferably the distances D1 and D2 for each of the two supports are of the same order. It is thus possible to adjust the penetration of the melted-blown fibers into the thickness of both the first nonwoven and the second nonwoven according to their first faces in order to adjust the inter-layer bond.

In a variant, the first nonwoven, optionally the second nonwoven, is a web of carded fibers, preferably non-elastic. In a variant, the thermoplastic elastomer comprises one or more polymers chosen from the following polymers: block copolymer of polyethylene and polypropylene, polyurethane, olefinic polymers, polyamide, polyethylene terephthalate, polyisoprene, polybutadiene, polystyrene, styrene and butadiene copolymer. The subject of the present invention is also according to a second aspect a device for implementing the method according to the invention comprising extrusion means and blowing means, able to form a web of molten-blown fibers, comprising a die extrusion blow-molding device comprising several rows of spinning orifices and blow-out orifices, said blowing means being arranged so as to produce a blown fluid, preferably in parallel flow and in the same direction, in a so-called blowing direction at through said blow holes surrounding each of said spinning orifices. Characteristically, the device comprises first and second means respectively for conveying a first nonwoven and a second nonwoven, said first and second conveying means being arranged so that the first faces of the first and second nonwovens serve as reception supports for said web of molten-blown fibers at the outlet of the extrusion-blowing die.

The web of molten-blown fibers or meltblown fleece thus comes into contact again in the softened state with the first faces of the first and second nonwovens at a time and thus adheres to said faces without requiring a second extrusion blow molding die arranged to form a meltblown veil on the first face of the second nonwoven as in the state of the art. In a variant, said first and second conveying means are arranged so as to convey the first nonwoven towards the second nonwoven up to a point of deflection and then to deflect the first and second nonwovens according to a so-called scrolling direction so that the first face of the first nonwoven is facing the first face of the second nonwoven. The inter-layer bond between the first and second nonwovens and the meltblown veil is obtained because of the only softened state of the meltblown veil. It is not necessary thus to carry out a hot calendering operation. Preferably, the extrusion blow die is disposed facing said point of deflection. In a variant, the device according to the invention comprises suction means arranged so as to produce a flow of suction air passing through said first and second nonwovens so as to facilitate the deposition of said melted-blown fibers on the first faces. first and second nonwovens.

In a variant, the first and second conveying means respectively comprise first and second deflection cylinders, the walls of which are optionally perforated. In a sub-variant, the first deflection roll and the second deflection roll are spaced apart by a distance suitable for receiving the first nonwoven, the meltblown cloth and the second nonwoven stacked in this order. The present invention will be better understood on reading the two exemplary embodiments, cited in a non-limiting manner, and in which: FIG. 1 is a schematic representation of a first example of a method for manufacturing an elastic nonwoven according to the invention; FIG. 2 is a schematic representation of a second example of a method for manufacturing an elastic nonwoven according to the invention; FIG. 3 is a schematic representation of an extrusion blow molding die used in the processes described in FIGS. 1 and 2 and - Figure 4 is a representation of the extrusion blow molding die shown in Figure 3, according to the sectional plane IV-IV.

The first example of a manufacturing method, illustrated in FIG. 1, comprises extrusion-blowing means 1 for the manufacture of an elastic meltblown veil 2. Said extrusion-blowing means 1 comprise an extruder 3, a die of 4 and blowing means 5 capable of producing a blown fluid in parallel flow and in the same direction in the direction of blowing (S). First conveying means 6 convey a first nonwoven 7 in a running direction (F) facing the extrusion blow die 4. The first nonwoven 7 also acts as reception support for said meltblown veil 2 The meltblown veil 2 is obtained by extrusion-blowing using the extrusion-blowing die 4 shown in FIG. 3. The meltblown veil 2 is thus deposited in the state still softened along the first face 7a of the first nonwoven. 7. The melted-blown fibers of the mettblown web 2 are oriented in the direction of blowing (S), which is secant, preferably substantially perpendicular to the direction of travel (F). According to the distance (D1) separating the spinning orifices 8 of the extrusion-blowing die 4 from the first face 7a of the first nonwoven 7, the speed [mis] and the flow [m3 / h] of the flow of at the outlet of the extrusion blow-molding die 4, it is possible to adjust the depth of penetration of the melted-blown fibers into the thickness of the first nonwoven 7 and thus to adjust the inter-layer bond 2, 7. Preferably, the first conveying means 6 comprise first suction means 9, which direct the deposition of the melted-blown fibers on the first face 7a of the first nonwoven 7 and allow according to the suction speed and the flow rate the air flow [m3 / h] also adjusts the depth of penetration of the melted-blown fibers into the thickness of the first nonwoven 7. The finished elastic nonwoven comprises two bonded layers 2.7. The first nonwoven 7 is preferably a web of carded fibers, possibly prelted, non-elastic.

The nonwoven resulting from the superposition of two layers 2.7 is elastic. Advantageously, it is not necessary to perform on the resultant nonwoven a drawing operation in at least one direction in order to impart elasticity in said direction. The nonwoven 10 is thus less mechanically degraded. The second example of a method according to the invention, illustrated in FIG. 2, differs from the first example in that it comprises second conveyor means 11 of a second nonwoven 12 arranged with respect to the first means of routing 13 of a first nonwoven 14 so as to convey the second nonwoven 12 to the first nonwoven 14 to a point of deflection (J), then to deflect the first 14 and second 12 nonwovens in said direction of travel (F) so that the first face 14a of the first nonwoven 14 is facing the first face 12a of the second nonwoven 12. In this particular example, the direction of blowing ( S) is substantially parallel to the scroll direction (F). The extrusion blow-molding die 4 is arranged opposite the point of deflection (J) so that the melted-blown fibers 17 are deposited both along the first faces 12a, 14a of the first 14 and second 12 nonwovens disposed. facing said die 4 and between said first 14 and second 12 nonwoven at the point of deflection (J). The first 13 and second 11 conveying means respectively comprise a first 15 and a second 16 deflection cylinders. Said deflection cylinders 15, 16 are preferably perforated and comprise suction means - not shown - arranged so as to generate a suction flow through said perforations improving the orientation and the deposition of the melted-blown fibers according to the first faces. 12a, 14a of the first 14 and second 12 nonwovens. The extrusion blow-molding die 4 used in the context of the invention thus makes it possible to dispose the die 4 with regard to both a first nonwoven 14 and a second nonwoven 12 so that the fibers blow-melts 17 are blown in a blowing direction (S) parallel to the running direction (F). Usually the extrusion blow dies having blowing means disposed on either side of a single row of spinning orifices are always arranged so that the blown-melted fibers are deposited by gravity on the receiving means. , especially from the top down. While in the present invention with individual blowing means for each blowing port, the melted-blown fibers can be blown in a horizontal direction, i.e. from left to right and vice versa. This arrangement advantageously makes it possible to dispense with a hot calendering operation since, according to the invention, the meltblown veil 17, still in the softened state, comes into contact with both the first 14 and the second 12 woven and thus ensures the connection between the three layers 12, 14, 17 to form an elastic nonwoven 18. The meltblown veil 2, 17 described in Figures 1 and 2 is obtained by extrusion blow molding through the extrusion die. blowing 4 shown in Figures 3 and 4. This die 4 is drawn from Figure 1 of US 5,476,616.

This is an example of extrusion blow molding die 4 suitable for implementing the method of manufacturing an elastic nonwoven fabric according to the invention. Said extrusion-blowing die 4 thus comprises several rows 19 of superimposed spinning orifices 8 and means capable of producing a blown fluid 20, preferably in parallel flow and in the same direction, in a blowing direction (S). through blow-out orifices 9 surrounding each of said spinning orifices 8. Each filament at the exit of a spinning orifice 8 is surrounded by a flow of air, and is therefore separated from the adjacent filaments. The meltblown veil 2, 17 obtained does not have aggregates of cured filaments that may limit the elastic properties of said veil 2, 17. The meltblown veil 2, 17 obtained also has more swelling. Of course, the structure of these extrusion blow dies is adaptable provided that each extruded filament is surrounded by said fluid blown out of its spinning orifice. It is thus possible to adjust the depth, the number and the diameter of the spinning orifices, the number of rows of spinning orifices and the structural means bringing the fluid through the blowing ports, in particular by means of baffles.

The blown fluid is preferably a gas, especially air,

Claims (14)

REVENDICATIONS1. A method of manufacturing an elastic nonwoven fabric (10, 18) comprising a step of forming a web of molten-blown fibers (2, 17) on a receiving medium (7, 12, 14) from an extrudable mixture comprising at least one thermoplastic elastomer, by means of extrusion means and blowing means (1, 3, 4, 5) comprising an extrusion blow die (4) characterized in that said extrusion blow-molding die (4) comprising several rows (19) of spinning orifices (8), the blowing is carried out, preferably in parallel flow and in the same direction, in a so-called blowing direction (5), at through blow holes (9) surrounding each of said spinning orifices (8). 2. Method according to claim 1, characterized in that it comprises the routing of a first nonwoven (7, 14) already formed in a running direction (F) under the extrusion blow molding die (4). ) so that the molten-blown fiber web (2, 17) is blown onto the first face (7a, 14a) of said first nonwoven (7, 14) as a receiving medium. 3. Method according to claim 2, characterized in that the blowing direction (S) is secant to the direction of travel (F), preferably the blowing direction (S) is perpendicular to the direction of travel (F). 4. Method according to claim 2, characterized in that it comprises the routing of the first (14) and a second (12) non-woven already constituted, and in that the routing of the first (14) and the second (12) nonwoven is made so as to convey the first nonwoven (14) to the second nonwoven (12), the web of molten-blown fibers (17) being blown onto the first face (12a). 14a) of both the first (14) and second (12) nonwovens up to a point of deflection (5) and then deflecting the first (14) and second (12) nonwovens according to said running direction (F) so that the first face (14a) of the first nonwoven (14) is facing the first face (12a) of the second nonwoven (12), the web of molten-blown fibers elastic member (17) being interposed between the two said first faces (12a, 14a), acting as reception support. 5. Method according to claim 4, characterized in that the extrusion-blow die (4) is disposed opposite said point of deflection (J). 6. Method according to one of claims 2 to 5, characterized in that said melted-blown fibers (2, 17) are sucked by a suction air flow passing through the first nonwoven (14), and optionally the second nonwoven (12), so as to facilitate the deposition of said melted-blown fibers (2, 17) on the first face (14a) of the first nonwoven (14), and optionally the first face (12a) of the second nonwoven (14); nonwoven (12). 7. Method according to one of claims 2 to 6, characterized in that the receiving medium (7, 12, 14) is disposed at a determined distance (D) from the spinning orifices (8), preferably less than 2 m, preferably less than 1 m. 8. Method according to one of claims 2 to 7, characterized in that the first nonwoven (14), optionally the second nonwoven (12), is a web of carded fibers, preferably non-elastic. 9. Method according to one of claims 1 to 8, characterized in that said thermoplastic elastomer comprises one or more polymers selected from the following polymers: block copolymer of polyethylene and polypropylene, polyurethane, polypropylene. 10. Device for implementing the method according to one of claims 1 to 9, characterized in that it comprises extrusion means and blowing means (1, 3, 4, 5), capable of forming a web of molten-blown fibers (2, 17), comprising an extrusion blow-molding die (4) comprising a plurality of rows (19) of spinning orifices (8) and blow-out orifices (9), said means for blowing (5) being arranged so as to produce a blown fluid (20), preferably in parallel flow and in the same direction, in a so-called blowing direction (S) through said blowing orifices (9) surrounding each of said orifice orifices; spinning (8) characterized in that it comprises first (13) and second (11) means for conveying respectively a first nonwoven (14) and a second (12) nonwoven, said first (13) and second (11) conveying means being arranged so that the first faces (14a, 12a) of the first (14) and second (1) 2) nonwovens act as reception supports for said web of molten-blown fibers (2, 17) at the outlet of the extrusion-blowing die (4). 11. Device according to claim 10, characterized in that said first (13) and second (11) conveying means are arranged so as to convey the first nonwoven (14) to the second nonwoven (12) until at a deflection point (3) and then deflecting the first (14) and second (12) nonwovens in a so-called scrolling direction (F) so that the first face (14a) of the first non-woven woven (14) facing the first face (12a) of the second nonwoven (12). 12. Device according to claim 11, characterized in that the extrusion-blow die (4) is disposed opposite said deflection point (3). 13. Device according to one of claims 10 to 12, characterized in that it comprises suction means arranged so as to produce a suction air flow through said first (14) and second (12) nonwovens in to facilitate the deposition of said melted-blown fibers (2, 17) on the first faces (12a, 14a) of the first (14) and second (12) nonwoven. 14, Device according to one of claims 10 to 13, characterized in that the first (13) and second (11) conveying means respectively comprise a first (15) and a second (16) deflection rolls, the walls are possibly perforated.