EP2467518A2

EP2467518A2 - Reinforcement comprising parallel rovings of glass strands

Info

Publication number: EP2467518A2
Application number: EP10754571A
Authority: EP
Inventors: Gilbert Chomarat
Original assignee: Chomarat Gilbert
Current assignee: Chomarat Gilbert
Priority date: 2009-08-21
Filing date: 2010-08-11
Publication date: 2012-06-27
Anticipated expiration: 2030-08-11
Also published as: ES2531429T3; EP2467518B1; WO2011021134A2; MY173520A; PL2467518T3; US20120148790A1; JP2013502516A; CA2771424A1; MX2012002001A; BR112012003544A2; FR2949239A1; PT2467518E; WO2011021134A3; CN102482815A; FR2949239B1; IL218141A0

Abstract

The reinforcement according to the invention comprises a reinforcement layer (2) based on parallel rovings (2a) of continuous glass strands, and one or two binding layers (3) consisting of portions of fibres having a heat-meltable surface. The assembly is consolidated by penetrating fibre portions (3b) that penetrate into the heat-meltable surface, these penetrating over a part of their length into the reinforcement layer (2) and adhering to the continuous glass strands of the rovings (2a).

Description

REINFORCEMENT WITH GLASS THREADS OF PARALLEL GLASSES

TECHNICAL FIELD OF THE INVENTION

The present invention relates to coherent and flexible textile reinforcement used as a reinforcing product of composite articles, that is to say of resin-based articles (polyester or other) reinforced with reinforcing fibers.

Numerous coherent reinforcing textile reinforcing structures consisting of one or more layers of fibers bonded together are already known.

The textile reinforcement is generally in the form of a flexible sheet packaged in a reel, which can thus be transported and handled at the place of use for the production of a composite article.

For the production of a composite article, the following procedure is generally carried out: a piece of appropriate surface of textile reinforcement is cut, it is placed in a mold, and a resin is penetrated which comes to drown the reinforcement in the mold. After polymerization, the resin and the reinforcement form a mechanically resistant structure.

The mechanical strength properties are obtained provided that the resin penetrates perfectly between the fibers forming the reinforcement, without leaving areas devoid of resin, and adhering perfectly to the fibers. It is also necessary that the fibers regularly occupy the volume of the composite article to be produced, in particular by following the shapes of the article when it is not flat.

Finally, it is necessary that the fibers themselves have a satisfactory mechanical strength to achieve an effective reinforcement.

Various reinforcing textile reinforcement structures have already been proposed.

Thus, the document EP 0 395 548 describes the use of two textile reinforcing layers, for example made of glass fibers, arranged on either side of a central layer constituted by a sheet of permanent-wave synthetic fibers. for example 40 to 70 mm long polyester fibers which have been texturized. The textile reinforcement layers are bonded to the central layer by stitching / knitting.

The document EP 0 694 643 describes the use of two textile reinforcing layers arranged on either side of a central layer giving the thickness of said material, the layers being bonded together by stitching / knitting, and it is provided against one of the outer faces a veil of synthetic fibers glued or sewn. Sewing / knitting techniques are relatively slow, and the textile reinforcement thus produced have non-uniform deformation capabilities, and surface appearance defects.

In order to increase the production rates and to reduce defects resulting from knitting, it has recently been proposed in documents FR 2 916 208 A1 and WO 2008/139423 A1 to produce a fiber-based textile reinforcement comprising a thick inner layer and aerated based on sections of synthetic fibers of 90 mm having received a treatment imparting a permanent crimp, and outer layers disposed on either side of the inner layer and comprising fiber sections with hot melt surface and reinforcing fibers 50 mm. At least some of the fiber sections with a hot-melt surface penetrate along part of their length into the inner layer and partially adhere to each other and to the synthetic fibers of the inner layer.

An advantage of this structure is to give textile reinforcements great flexibility and great deformation capacity to follow the shapes of complex molds, the crimped synthetic fibers ensuring the maintenance of a sufficient volume of the inner layer for good penetration of the resin during subsequent molding.

Reinforcing fibers such as fiberglass stretches of

50 mm, present in the outer layers, improve the mechanical characteristics of the composite article. But this improvement is small, because these reinforcing fibers are short and necessarily small, the proportion of glass fibers being limited by the presence of predominant synthetic fibers permanently crimped. For some applications, it remains desirable to significantly increase the mechanical characteristics of the composite article, including its resistance to rupture or bending.

According to a technique known for a long time and described in the document FR 1 394 271 A, then more recently taken up in the document EP 1 125 728 A1, strands of parallel glass fibers originating from a coil or "roving" are arranged side by side in a sheet and glued on a woven or non-woven fiber support which assembles them. Such wicks arranged side by side constitute a continuous band structure, with a weight of 500 to 1500 g / m ² .

The term "wire" refers to a set of single glass filaments, which generally have a diameter of 5 μm to 24 μm. A thread usually includes the order of 40 filaments. A set of threads is called a wick. A wick generally comprises about 50 wires.

The disadvantage of this known technique is the necessary presence of an adhesive to ensure the cohesion of the reinforcing product during its handling before injection molding. Indeed, the glue is likely to reduce the penetration capacity of the resin during molding, and to reduce the short or long term mechanical strength of the composite article from the molding.

Until now, in the coherent reinforcements based on unidirectional strands of glass fibers, the locks are assembled by stitching, which is a relatively slow process, and there is a need to increase substantially the speed of production of the textile reinforcements, to reach speeds of over

10 m / min.

The invention goes against these difficulties and makes it possible to solve them.

SUMMARY OF THE INVENTION

The problem proposed by the present invention is to substantially increase the mechanical strength of the composite articles made from glass fiber molding reinforcements, while retaining the properties of consistency, flexibility and deformability of the molding reinforcements before molding, and retaining good properties of penetration and printing of the resin during molding.

Simultaneously, the invention aims to design a molding reinforcement that can be produced at high speed, reaching speeds of more than 10 m / min.

In addition, the invention proposes to improve if necessary the regularity of the surface of the composite articles made by molding the molding reinforcements.

Preferably, the invention also aims to allow the realization of reinforcing products continuous web, can be packaged in a coil, and can be cut or cut without risk of fraying or degradation of the edges.

To achieve these and other objects, the invention provides a fiber-based web molding reinforcement comprising:

a first layer of fibers,

at least one bonding layer in sections of fibers with a hot-melt surface, bonded to the first layer of fibers, at least some of the thermofusible surface fiber segments penetrating along part of their length into the first layer of fibers and partially adhering to each other and to the fibers of the first layer of fibers,

and wherein the first fiber layer comprises strands of parallel glass strands disposed side-by-side in a sheet, thereby forming a reinforcing layer.

The thermofusible surface fibers of the bonding layer ensure the effective bonding of the strands of glass son without external glue, while maintaining flexibility and regularity of the molding reinforcement, and without deforming or breaking the glass son.

Simultaneously, such a molding reinforcement structure can be realized at a high speed, since interpenetration of the hot-melt surface fibers can be achieved by a light needling step, which is much faster than the sewing process.

Preferably, the sections of thermofusible surface fibers that penetrate the reinforcing layer are relatively spaced from each other, this spacing being equal to or greater than the needle pitch of a light needling: the surface density of such a light needling is about 5 to 10 needle penetrations per cm ² of backing layer. This results in a reduction of the bending stresses exerted on the glass fibers, and a corresponding reduction in the risks of rupture of the glass fibers.

The invention thus makes it possible to use the excellent mechanical properties of the unidirectional wicks of glass fibers, conferring excellent mechanical properties on composite articles made by molding such a reinforcement. The bonding layer, of which certain fiber sections penetrate and adhere to the fibers of the reinforcing layer, provides a sufficient temporary retention of the glass strands of the reinforcing layer after manufacture and before use of the molding reinforcement, conferring on the molding reinforcement a satisfactory coherence.

At the same time, the penetrating and adherent fiber bonding layer makes it possible to maintain the glass strands with only a small amount of material other than glass, that is to say by maximizing the relative amount of glass in the reinforcement. molding.

The bonding layer may be particularly thin, in the form of a web of fibers, for example with a basis weight of about 25 to 30 g / m ² .

The strands of glass strands may advantageously have a titer of between 2,400 and 4,800 tex approximately. In such a wick the glass strands may advantageously be formed of an assembly of filaments having a unit diameter of between about 14 microns and about 17 microns.

Alternatively or in addition, the glass strands of the wicks may have a unitary title of 40 to 80 tex approximately.

According to a first embodiment, the reinforcing layer is bonded to a single heat-fusible surface fiber bonding layer.

According to a second embodiment, the reinforcing layer is bonded to two heat-fusible surface fiber bonding layers disposed on either side of the reinforcing layer.

According to a third embodiment, in a structure of one of the preceding embodiments, there is further provided an intermediate layer of glass son between the reinforcing layer and the bonding layer.

The intermediate layer may comprise a layer of glass threads of approximately 160 to 200 tex, parallel and oriented perpendicularly to the wicks, and / or a layer of glass fibers cut at approximately 50 mm, in bulk at all orientations, according to a weight of Approximately 50 to 80 g / m ² .

Advantageously, the molding reinforcement according to the invention may have a grammage of between 400 and 1800 g / m ² . This provides a good compromise between the thickness of the molding reinforcement and its deformation capacity before molding. For example, with five locks of 2400 tex per cm is produced a weight of 1200 g / m ² .

According to another aspect, the invention proposes a method of manufacturing such a molding reinforcement, comprising the steps of:

a) on a support, depositing side by side a plurality of strands of parallel glass son, to form a sheet of strands of glass son constituting a reinforcing layer,

b) depositing, on the reinforcing layer, a web of chemical fibers with a hot-melt surface, constituting a tie layer,

c) lightly needling to penetrate sections of thermofusible surface fibers of the tie layer in the reinforcing layer, d) heating the assembly to a temperature sufficient to soften and sticky the hot melt surface fibers,

e) cold calendering the whole.

In the case of a reinforcement with two bonding layers, in step a) a second web of chemical fibers with a hot-melt surface is placed on the support, constituting a second bonding layer, and then the strands of glass strands on the second bonding layer; in step c), a light double-sided switch is made.

In the case of an intermediate layer reinforcement, between step a) and step b), the pre-cut yarns or glass fibers of the intermediate layer are placed on the reinforcing layer.

Preferably, during the light needling step, needles are used whose driving barbs are placed in a diametral plane parallel to the direction of the son son of glass strands. In this way, it is avoided to break the glass son, and it is guaranteed to obtain a reinforcement providing a high mechanical strength to composite articles made from such a reinforcement.

SUMMARY DESCRIPTION OF THE DRAWINGS

Other objects, features and advantages of the present invention will become apparent from the following description of particular embodiments, with reference to the accompanying figures, in which:

- Figure 1 is a schematic longitudinal sectional view of a molding reinforcement according to a first embodiment of the invention;

- Figure 2 is a schematic perspective view of a wick of continuous glass son, partly exploded;

- Figure 3 illustrates in perspective a continuous glass wire;

- Figure 4 is a schematic longitudinal sectional view of the molding reinforcement of Figure 1, during light needling;

- Figure 5 is a schematic perspective view of a molding reinforcement according to one embodiment of the invention;

- Figure 6 illustrates the orientation of the barbs driving the needles during light needling;

- Figure 7 is a schematic longitudinal sectional view of a molding reinforcement according to another embodiment of the invention; and

- Figure 8 is a schematic longitudinal sectional view of a molding reinforcement according to another embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In a first embodiment illustrated in FIGS. 1 and 5, a molding reinforcement 1 according to the invention comprises two fiber layers, namely a reinforcing layer 2 and a bonding layer 3.

The reinforcing layer 2 comprises strands of glass strands, such as the strands 2a, 2b, 2c (FIG. 5), which are parallel and arranged side by side in a single layer of strands. By way of illustration, FIG. 2 represents such a wick 2a or bundle of wires such as the wires 20a, 20b, 20c, generally parallel to one another. In the wick 2a, the continuous wires 20a, 20b, 20c are normally in contact with each other. In Figure 2, the wick 2a is shown partially exploded, the son 20a, 20b, 20c deviating from each other in the right portion of the figure for a better understanding of the wick structure. In a molding reinforcement, the wires 20a, 20b, 20c remain in contact with each other.

To obtain a good mechanical resistance to the elongation, it will be advantageous to choose strands of continuous glass strands 20a (FIG. 3), originating from a coil or "roving". The son are formed of an assembly of filaments such as filaments 200a, 200b, 200c whose unit diameter is between about 14 microns and about 17 microns. The unitary title of the glass strands 20a, 20b, 20c may for example be between 40 and 80 tex, by assembling about 50 glass filaments.

The wires 20a, 20b, 20c are actually formed of a sufficient number of filaments to prevent them from breaking during handling and use according to the invention, it being observed that the isolated filaments, in the size in which they usually come out of manufacturing, are too fragile for such manipulations and uses.

Alternatively, in order to obtain an elongation capacity of the molding reinforcement 1 before the molding step, strands of cut glass strands, having a length of about 10 cm to about 100 cm, are advantageously chosen, the strands being able to be offset longitudinally. relative to each other to overlap each other, and remaining each formed of an assembly of filaments. The length of such son is sufficient to ensure good mechanical properties to the composite article made by molding this molding reinforcement 1, and the elongation capacity improves the adaptation to a pre-existing object, for example to a tube for the covering of its outer or inner surface. This embodiment allows for example an application to the renovation of pipes in the basement.

The bonding layer 3 comprises fiber sections 3a with a hot-melt surface.

The fiber sections 3a with a hot-melt surface may be of any material having a sufficiently low melting temperature and good bonding properties with the glass strands 20a, 20b, 20c of the reinforcing layer 2.

Alternatively, the fiber sections 3a with a hot-melt surface may be two-component chemical fibers, comprising a central core in polyamide, polyester or polypropylene, and an outer sheath of copolyester, polyethylene or any other material having a lower melting temperature than that of the central core. Good results can be obtained by using a central core made of polyester and an outer sheath made of copolyester, or a central core of polypropylene and an outer sheath of polyethylene. Other pairs of materials can be used as coaxial two-component fibers: polypropylene and copolypropylene, polypropylene and ethyl vinyl acetate.

In that the central core of the two-component fiber has a higher melting temperature than the outer sheath, an accidental risk of complete melting of the first sections of hot-melt-surface fibers is avoided during the manufacture of the molding reinforcement. 1.

It is also effective to limit the risk, during a heating step for the manufacture of the molding reinforcement 1, that the hot-melt fiber sections are, by excessively high or poorly controlled heating, completely melted, forming uniform or impervious layers. to the resin by spreading their constituent material on the upper and lower faces of the reinforcing layer 2. The core of the bi-component fibers is not (or very little) impaired, and the properties of the tie layer 3 are thus preserved.

In addition, the use of bi-component hot-melt surface fibers outer sheath and central core reduces the polyolefin content of the molding reinforcement 1. This is advantageous, the resin being incompatible with the polyolefins.

Among the fiber sections 3a with a hot-melt surface of the connecting layer 3, at least some of these sections, for example the penetrating sections 3b in FIG. 1, penetrate along part of their length in the reinforcing layer 2 and partially adhere to each other. between them and the glass wires 20a, 20b, 20c of the reinforcing layer 2.

The penetrating sections 3b of fibers are regularly distributed along the surface of the molding reinforcement 1, for example at a surface density of 5 to 10 sections per cm ² of molding reinforcement, and ensure cohesion of the assembly, while retaining the deformability and flexibility properties of the molding reinforcement 1.

The molding reinforcement 1 according to the invention can be produced in the form of a continuous strip which is packaged in a long coil. In such a continuous strip, the locks 2a, 2b, 2c are formed of continuous glass threads 20a,

20b, 20c and are oriented in the direction of the strip length, or warp direction. For example, a ply of strands of glass strands is deposited on a flat support to constitute the reinforcing layer 2, a layer of fibers with a hot-melt surface is deposited on the reinforcing layer 2 to constitute the bonding layer 3.

The assembly thus obtained is subjected to a light needling which penetrates at least 3b of the fiber sections 3a with hot-melt surface of the bonding layer in the reinforcing layer 2, the whole is heated to a temperature sufficient to soften the thermofusible portion of the penetrating sections 3b of thermofusible surface fibers and to ensure after cooling their bonding to the glass son 20a, 20b, 20c of the reinforcing layer 2.

FIG. 4 diagrammatically illustrates the light needling operation, in which pre-needling needles 8 are distinguished, which result in penetrating sections 3b of fibers with a hot-melt surface so that they penetrate into the reinforcing layer 2.

The light needling carried out for example produces a surface density of perforations of about 5 to 10 perforations per cm ² . This must be compared to needling processes which typically achieve densities at least 10 times higher. The light needling allows a large flow during the manufacture of the molding reinforcement according to the invention.

As illustrated in FIG. 6, during light needling, the entrainment barbs such as the barbs 8a and 8b of the needles 8 are placed in a diametral plane containing the axis of the needle and parallel to the direction D of the pins. threads of glass strands such as wick 2a. Due to the axial movement (arrow 8c) of the needle 8 during needling, the barbs 8a and 8b pass through the locks 2a by spacing the son 20a, 20b, 20c (Figure 2) without breaking them.

The light needling performed is sufficient to ensure cohesion during the transfer of the molding reinforcement blank to a next work station, but it is insufficient to ensure the final cohesion of the molding reinforcement 1 and it is still not transportable at the exit of the needling machine for use as reinforcement.

The heating which is performed after the light needling operation makes it possible to soften the hot-melt surface layer of the penetrating sections 3b of fibers of the tie layer 3 to make it adherent. The penetrating sections 3b of fibers which have been driven by the light needling needles 8 adhere to the glass strands 20a, 20b, 20c of the reinforcement layer 2. After cooling, the various layers 2, 3 of the molding reinforcement 1 are thus bonded together by the 3b needled and glued fibers. The molding reinforcement 1 is then transportable. The heating is set to soften and adhere the penetrating sections 3b of hot-melt surface fibers, but without melting them.

FIG. 8, which schematically illustrates a second embodiment of the molding reinforcement according to the invention, is now considered.

This second embodiment is distinguished from the first embodiment of FIG. 1 by the additional presence of a second bonding layer 4 on the other side of the reinforcing layer 2. Each bonding layer 3 or 4 is based on of hot-melt surface fibers.

Penetrating sections 3b and 4b of thermofusible surface fibers are found which solidify the layers 2, 3 and 4.

FIG. 7, which schematically illustrates a third embodiment of the molding reinforcement according to the invention, is now considered.

This third embodiment is distinguished from the first embodiment of FIG. 1 by the additional presence of an intermediate layer 5 of glass fibers between the reinforcing layer 2 and the bonding layer 3.

According to a first possibility, the intermediate layer 5 comprises a layer 5a of glass threads of about 160 to 200 tex, parallel and oriented perpendicular to the wicks 2a, 2b and 2c, that is to say in the weft direction, and continuous along the entire width of the reinforcement.

According to a second possibility, the intermediate layer 5 comprises a layer 5b of glass fibers cut about 50 mm, in bulk at all orientations, with a weight of 50 to 80 g / m ² approximately.

According to a third possibility, illustrated in FIG. 7, the intermediate layer 5 comprises a layer 5a of glass threads in the weft direction and a layer 5b of bulk cut glass fibers.

This third embodiment is suitable for applications requiring transverse reinforcement in the weft direction, and can improve the surface regularity of the composite article.

Penetrating sections 3b of thermofusible surface fibers are found which solidify the layers 2, 3 and 5.

Example

I) on a flat support, several strands of glass strands are deposited, laying them parallel in sheet and in a single thickness to form a reinforcing layer 2. The glass strands are formed of a

40 filaments having a unit diameter of about 15 μm, the threads having a title unitary of about 50 tex. The locks have a title of 2400 tex, and are present in quantity of five locks per cm.

Il) on a conventional card, a web of chemical fibers with a hot-melt surface is produced. The chemical fiber sections consist of bicomponent fibers, with a central polyester core and a thermofusible copolyester outer sheath. The thermofusible outer copolyester sheath has a melting temperature of about ^110.degree .

The two-component chemical fibers have a unit title of between about 2 deniers and about 4 deniers.

III) depositing the web of chemical fibers with a hot-melt surface on the reinforcing layer 2.

IV) the molding reinforcement blank thus produced is introduced by means of a conveyor belt into a needling machine. The density of the needles is 10 / cm ² . The penetration depth of the needles is 12 mm. The running speed of the carpet is 20 m / minute.

V) after the light needling operation, the molding reinforcement blank is introduced into a through air oven having a heating portion of 12 m length and a running speed of 20 m / min. The temperature of the through air oven is approximately 120 ^° C.

VI) at the outlet of the through-air oven, a cold calendering is carried out which gives the molding reinforcement 1 its final thickness which is close to

4 to 5 mm.

The basis weight of the molding reinforcement 1 is between 400 and

About 1800 g / m ² .

The molding reinforcement 1 according to the invention can find advantageous applications in the manufacture of long composite parts, in particular wind turbine blades.

The present invention is not limited to the embodiments which have been explicitly described, but it includes the various variants and generalizations thereof within the scope of the claims below.

Claims

1 - Fiber-based web molding reinforcement (1), comprising:

a first layer of fibers (2),

at least one bonding layer (3) in fiber sections (3a) with a hot-melt surface, bonded to the first fiber layer (2),

- at least some (3b) sections (3a) of thermofusible surface fibers penetrating along part of their length into the first layer of fibers (2) and partially adhering to each other and to the fibers of the first layer of fibers (2) ,

characterized in that the first fiber layer (2) comprises wicks (2a, 2b, 2c) of glass wires (20a ₁ 20b, 20c) parallel and arranged side by side in a sheet, thereby forming a reinforcing layer.

2 - molding reinforcement according to claim 1, characterized in that the wicks (2a, 2b, 2c) of glass son have a title of 2400 to 4800 tex approximately.

3 - molding reinforcement according to one of claims 1 or 2, characterized in that the glass son (20a, 20b, 20c) wicks (2a, 2b, 2c) are formed of an assembly of filaments having a diameter unitary between about 14 microns and about 17 microns.

4 - molding reinforcement according to any one of claims 1 to 3, characterized in that the glass son (20a, 20b, 20c) wicks (2a, 2b, 2c) have a unit title of 40 to 80 tex approximately .

5 - molding reinforcement according to any one of claims 1 to 4, characterized in that the penetrating fiber sections are distributed at a surface density of 5 to 10 sections per cm ² of molding reinforcement.

6 - molding reinforcement according to any one of claims 1 to 5, characterized in that it comprises an intermediate layer (5) of glass son between the reinforcing layer (2) and the connecting layer (3).

7 - molding reinforcement according to claim 6, characterized in that the intermediate layer (5) comprises a layer (5a) of glass son of 160 to 200 tex, parallel and oriented perpendicular to the wicks (2a, 2b 2c), and / or a layer (5b) of glass fibers cut about 50 mm in length, in bulk at all orientations, with a basis weight of about 50 to 80 g / m ² .

8 - molding reinforcement according to any one of claims 1 to 7, characterized in that the reinforcing layer (2) is bonded to a single bonding layer (3) of hot-melt surface fibers.

9 - molding reinforcement according to any one of claims 1 to 7, characterized in that the reinforcing layer (2) is bonded to two bonding layers (3,4) made of fibers with a hot-melt surface, arranged on either side of the reinforcing layer (2).

10 - molding reinforcement according to any one of claims 1 to 9, characterized in that it has a basis weight between 400 and 1800 g / m ² .

1 1 - molding reinforcement according to any one of claims 1 to 10, characterized in that it is in the form of continuous strip packaged coil, the wicks (2a, 2b, 2c) being formed of continuous glass son ( 20a, 20b, 20c) and being oriented in the direction of the strip length.

12 - molding reinforcement according to any one of claims 1 to 10, characterized in that it is in the form of continuous strip packaged coil, the wicks (2a, 2b, 2c) being formed of glass son 10 to 100 cm in length and oriented in the direction of the strip length.

13 - A method of manufacturing a molding reinforcement according to any one of claims 1 to 12, comprising the steps of:

a) on a support, depositing side by side a plurality of wicks (2a, 2b, 2c) of parallel glass threads, to form a sheet of strands of glass son constituting a reinforcing layer (2),

b) depositing, on the reinforcing layer (2), a web of chemical fibers with a hot-melt surface (3a) constituting a tie layer (3),

c) Lightly needling to penetrate sections

(3b) of thermofusible surface fibers of the bonding layer (3) in the reinforcing layer (2),

d) heating the assembly to a temperature sufficient to soften and make sticky the hot melt surface fibers (3a),

e) cold calendering the whole.

14 - Process according to claim 13, characterized in that, during the light needling step c), needles (8) are used whose driving barbs (8a, 8b) are placed in a diametral plane parallel to the direction (D) of the son of the strands of glass son (2a, 2b, 2c).

15 - Application of a molding reinforcement according to any one of claims 1 to 12 for the manufacture of wind turbine blades or other long composite parts.