NON-WOVEN TEXTILE FABRIC, SUITABLE FOR FORMING A MECHANICAL REINFORCEMENT LAYER IN A COMPOSITE MATERIAL

Abstract

Non-woven textile fabric, adapted to form a permeable layer in a composite material, said fabric being made from chopped glass fibers, and incorporating means ensuring the bonding of said glass fibers together, characterized in that it comprises at least two types of glass fibers, namely: - on the one hand, fibers of a first type, from chopped rovings, having a sizing of a first type; and on the other hand, fibers of at least one of the following two types, namely: - fibers of a second type, from direct rovings, having a sizing of a second type, different from the sizing of the first type; - fibers of a third type, free from sizing.

Description

Title of the invention: NON-WOVEN TEXTILE FABRIC, SUITABLE FOR FORMING A MECHANICAL REINFORCEMENT LAYER IN A COMPOSITE MATERIAL Technical field

[0001] The invention relates to the field of technical textiles, and more particularly to textiles used for the manufacture of composite materials, that is to say, materials combining one or more textile layers impregnated with a material in liquid phase during its application, and then intended to solidify subsequently. These materials may be of various types, thermosetting or thermoplastic, or even bituminous or cementitious.

[0002] More specifically, the invention relates to a mat more specifically based on cut glass fibers, made from a mixture of different types of fibers, including in particular fibers from recycling.

[0003] The invention also relates to the use of this type of reinforcement for the manufacture of different kinds of composite materials. Previous techniques

[0004] Generally speaking, textile mats are non-woven fabrics made up of fibers, most often cut, which are oriented in a nearly random fashion and combined to give this set of fibers a certain cohesion. The assembly can be carried out by various processes, of a mechanical nature, for example by needle punching, sewing or carding, or of a chemical nature, by the incorporation of binders in the form of powder, hot-melt filaments, or sprayed droplets.

[0005] For mats intended for reinforcement, the use of high-tenacity fibers such as glass is standard practice. The mats are manufactured from bundles of filaments, or rovings, which are generally cut to form fiber segments of a predetermined length. To ensure a nearly isotropic distribution of fiber orientation, the rovings are cut at a certain height above the plane on which the mat will be formed, and the fall of the cut fibers causes them to be randomly oriented when they reach the reference plane. For the manufacture of this type of product, so-called "cut rovings" or "assembled rovings" are used. These rovings were developed by glassmakers exclusively for the production of glass mats and have the advantage of possessing very regular geometric and mechanical properties.

[0006] One of the advantages of this type of roving lies in the use of certain types of sizing that coat the individual filaments of the roving. Indeed, for the For cutting rovings, the sizing can be applied to a bundle of filaments gathered into small bundles. After the sizing has dried, the bundles are re-bundled into a roving. When cutting a cutting roving, the filaments remain bundled together, which has the advantage of facilitating cutting and ensuring the isotropy and relatively thinness of the resulting mat.

[0007] Traditionally, the manufacture of fiberglass mats therefore requires the use of glass rovings that have been manufactured specifically for this purpose, particularly with regard to sizing, and hereinafter referred to as "cutting rovings". Description of the invention,

[0008] Furthermore, in the field of technical textiles, and particularly glass fiber textiles, a large quantity of waste is produced. This can include, for example, waste generated during the manufacture of textile articles, such as selvedges, which are cut off the end of the loom. It can also include offcuts generated during fabric cutting, or mats from the production of shaped pieces, or even rolls of second-grade material. The rovings used for the manufacture of these articles differ from cutting rovings with regard to the sizing agents used.Indeed, for rovings used, for example, in weaving glass fabrics or in manufacturing non-corrugated fiber (NCF) fabrics, the glass filaments are bundled together in a single bundle, and the sizing coating is formulated to allow the filaments to move relative to each other, thus facilitating yarn spreading. This type of roving is generally called "direct roving."

[0009] There are also other types of waste generated when textiles are used in the manufacture of composite materials. For example, when producing shaped composite parts, offcuts are generated, which include the textile itself combined with a thermosetting or thermoplastic resin. This waste can also come from end-of-life products, including composites.

[0010] One of the objectives of the invention is to enable the recovery of these different wastes by their reuse in the manufacture of reinforcement mats.

[0011] To this end, the Applicant has designed a specific textile fabric. In a conventional manner, this non-woven fabric, which is suitable for forming a permeable layer in a composite material, is made from chopped glass fibers, and incorporates means ensuring the bonding of these fibers.

[0012] According to the invention, this fabric comprises at least two distinct types of glass fibers, namely: - on the one hand, fibers of a first type, derived from cut rovings, which exhibit a first type of sizing, and on the other hand at least one of the following two types of fibers, namely: - fibers of a second type, from direct rovings, which have a sizing of a second type, different from the sizing of the first type, - fibers of a third type, free from sizing.

[0013] In other words, the invention therefore consists of producing the mats by combining several types of glass fibers from different origins. Part of these fibers comes from rovings dedicated to the manufacture of mats, in other words, first-hand fibers, or "virgin" fibers.

[0014] Another portion of the fibers may come from recycling, specifically from fibers sourced from production selvedges, recycled fabrics, but also from hardened composite materials, or from pre-impregnated and recycled textiles. The composite materials may come from machining waste or end-of-life products.

[0015] The sizing used for direct rovings does not allow the fibers to be bundled together, unlike the sizing used for fibers from cut rovings. Surprisingly, the coexistence of these two sizings in the mat of the invention is not a hindrance to the manufacturing and cohesion of the mat.

[0016] Similarly, the fibers obtained from the recycling of composite materials had to undergo steps to remove the thermosetting or thermoplastic resin that impregnates the fibers. This removal, by thermal or chemical means, also eliminates the sizing that coats the glass fibers. Surprisingly, cutting these recycled fibers to the desired length for the mat, as well as incorporating them into the mat itself, is done without any major negative effects that might have been expected given the absence of sizing on these fibers.

[0017] In one embodiment, the fabric comprises at least three types of glass fibers, namely: - fibers of a first type, from cut rovings, exhibiting a sizing of a first type;

[0018] - fibers of a second type, derived from direct rovings, exhibiting a sizing of a second type, different from the sizing of the first type; - fibers of a third type, free from sizing

[0019] In practice, the means of bonding the fibers together can be of various kinds. For example, it can be a binder, formed by a powder, or by fibers that are at least partially fusible on the surface, which, after softening or even melting, can bond the different fibers with which they are in contact, or even by sprayed droplets of glue. Bonding can also be achieved by a mechanical action on the glass fibers themselves, in particular by needle punching, so that the fragments of these glass fibers pass through all or part of the thickness of the fabric to mechanically ensure the cohesion of the mat through phenomena of friction. It is also possible to hold the fibers together by sewing operations.

[0020] In practice, in a specific embodiment, the average length of the fibers of the first type may be greater than the average length of the fibers of the second and / or third type. In other words, fibers from cut rovings are longer than recycled fibers, which have generally undergone breakage during the recycling steps that allow them to be extracted from their original fabrics or mats and cut to the desired length.

[0021] In practice, it is generally observed that the standard deviation of fiber length of the first type is less than the standard deviation of fiber length of the second and / or third type. In other words, fibers from cut rovings are very uniform in length, as this depends only on the settings of the cutting tool. Conversely, recycled fibers vary considerably in length, depending on the dimensions of the article portions from which they are recycled, as well as the sequence of the different operations used to cut and / or shred the textile waste to be recycled.

[0022] In practice, the fibers of the first type, i.e. from cut rovings, have an average length of between 25 and 100 millimeters, while the fibers of the second type, from for example from weaving scraps, have an average length of between 15 and 50 millimeters, while the fibers of the third type, from recycling of composite articles, have an average length of between 15 and 50 millimeters.

[0023] Depending on the desired applications, in terms of mechanical properties, and resin of the composite material in which the mat is integrated, different configurations are conceivable with regard to the proportion of the different types of glass fiber within the mat.

[0024] Thus, in a first scenario, the proportion by weight of glass fibers is: - for fibers of the first type, between 25 and 50%; - for fibers of the second type and / or the third type, each comprising between 25 and 50%;

[0025] This distribution configuration is more particularly intended for masts used for example as a support for a bituminous coating, or as a reinforcement layer in a board.

[0026] In another scenario, the proportion by weight of glass fibers may be: - for fibers of the first type, between 50 and 80%, - for fibers of the second and / or third type, each comprising between 5 and 50%.

[0027] This type of reinforcement is, for example, intended for applications of reinforcing thermosetting matrix composite material.

[0028] In a third scenario, the proportion by weight of glass fibers may be: - for fibers of the first type, between 5 and 20%,

[0029] - for the second and third type fibers, each comprising between 30 and 55%.

[0030] This configuration is particularly intended for applications in the manufacture of composite materials, such as for example surfboards.

[0031] In practice, the fibers of the thermoplastic materials at least partially fusible ensuring the bonding of the glass fibers can be made of a material chosen from the group including polyesters, co-polyesters, co-polyolefins and copolyamides, taken alone or in mixture with one or more materials chosen from the group including polyolefins, polyesters and polyamides.

[0032] In a particular embodiment, the majority of the first-type fibers are gathered in a first fraction of the fabric thickness, while the second- and / or third-type fibers are gathered in a different fraction of the fabric thickness. In other words, the fibers from cut rovings form a sublayer distinct from the sublayer comprising the recycled fibers. These two sublayers can be joined by mechanical action, such as stitching or needle punching, or by bonding, for example, using a binder that ensures the cohesion of the fibers. This structure can, for example, be obtained by depositing fibers from cut rovings on and / or under a fibrous web composed primarily of recycled fibers, from direct rovings and / or from the recycling of composite parts.This stacking of different fibers within the same product makes it possible to achieve mats that are thinner than in previous cases, and also have greater mechanical properties.

[0033] In a particular embodiment, the fabric described above can be used to form a composite comprising an additional layer consisting of a woven fabric, a unidirectional yarn web, a mat, a fabric based on non-curved fibers (NCF), or a polypropylene fiber mat, for example. Composites can also be made by stacking several of the fabrics described above.

[0034] In other words, it is possible to use the characteristic mat in association with reinforcement layers having higher a priori mechanical properties, because these are structures having continuous yarns in the case of fabrics and NCFs, or because it is a mat made essentially or even exclusively from cut rovings.

[0035] Of course, this combination can be adapted to different applications, using alternating layers of mat containing recycled fibers and layers additional materials based on fabrics, NCF or mats with high mechanical properties.

[0036] In some cases, the complex may comprise a first layer formed by a mat composed essentially, or even exclusively, of the first type of fibers, namely fibers from cut rovings. The second layer is also a mat, composed of a mixture of fibers of the first type, from cut rovings, and one or more types of recycled fibers, that is to say, either fibers from the recycling of an unimpregnated textile, i.e., from direct rovings, or fibers from the recycling of impregnated textiles. In other words, the complex is obtained by assembling pre-existing layers, which are joined together by sewing, gluing, or other mechanical and / or chemical action.

[0037] In general, the mats or complexes according to the invention can advantageously be used for the manufacture of composite materials including a thermosetting resin, or a bituminous base and, more generally with any low viscosity matrix, such as that used in resin transfer moulding (RTM), pultrusion, infusion, or even hand lay-up (HLU) processes, as opposed to thermocompression processes which use high viscosity matrices. Examples of completed projects

[0038] As already mentioned, the invention relates to a mat or a complex incorporating this mat, made from three different types of glass fibers.

[0039] The various examples described below were made from fibers of the three types, according to different varieties as defined below:

[0040] For the first type, i.e. cutting rovings, two varieties were used.

[0041] The first variety (TlVI) corresponds to fibers from cut rovings marketed by the company OWENS CORNING having a count of 2400 tex. These rovings have a sizing of the commercial reference P244, and are cut to lengths of approximately 50 mm.

[0042] The second variety (T1V2) corresponds to fibers from cut rovings marketed by the company SISECAM CAM ELYAF having a count of 2400 tex. These rovings have a coating of the commercial reference KCR10, and are cut to lengths of approximately 50 mm.

[0043] For the second type, that is to say the fibers from textile waste, coming almost exclusively from direct rovings, tests were carried out with different varieties.

[0044] A first variety (T2V1) is formed from a mixture of substantially equal weights of three categories of fibers. A first category (T2V1C1) is formed from scraps The first category consists of selvedges recovered from the loom, made from yarns from companies 3B and OWENS CORNING with a count of 200 to 4800 tex, and bearing a sizing with the reference 111 A. This first category has an average fiber length of between 30 and 40 millimeters, obtained without further cutting. The second category (T2V1C2) is formed from selvedges of multiaxial fabrics, based on 600 tex fibers, bearing a sizing with the reference 111A from OWENS CORNING. This second category has an average length of approximately 25 mm, with a high degree of variation in length because the waste was initially 200 mm and then cut by guillotine to a target of 25 mm. The third category (T2V1C3) is composed of fibers obtained from the scraps of a complex marketed under the reference G-PLY by the Applicant.This complex comprises several layers of fabric made from yarns of 600 and 1200 tex count, bonded to a 30 g / m² glass fiber veil with a polyester binding thread. The glass fibers in this third category also incorporate a sizing of commercial reference 111A from company 3B. The length of these fibers in this third fraction is approximately 25 millimeters.

[0045] A second variety (T2V2) is formed from a substantially equal weight blend of two fiber categories. A first category (T2V2C1) is formed from selvedge scraps recovered from the loom, made from OWENS CORNING yarns with a count of 200 to 2400 tex, and bearing a sizing with the reference SE1200. This first category has an average fiber length of between 20 and 40 millimeters. The second category (T2V2C2) is composed of fibers obtained from scraps of a composite fabric marketed under the Applicant's reference G-PLY. This composite comprises several layers of fabric based on yarns with a count of approximately 200 tex, bonded to a 30 g / m² glass fiber web by stitching with a polyester binding thread. The glass fibers in this second category also include a coating of the commercial reference SE1200 from the company OWENS CORNING.The length of these fibers in this third fraction is approximately 25 millimeters.

[0046] A third variety (T2V3) is formed from selvedge scraps recovered from the loom, from yarns of the company CPIC with a count of 200 to 2400 tex depending on the type of recycled fabric, and having a sizing bearing the reference 469L. This third variety of fibers has an average fiber length of between 20 and 40 millimeters, and is used without further cutting.

[0047] A fourth variety (T2V4) is formed from a substantially equal weight mixture of three fiber categories. A first category (T2V4C1) is formed from selvedge scraps recovered from the loom, from PPG yarns with a count of 200 to 2400 tex, and bearing a sizing with the reference 2002. This The first category has an average fiber length of between 20 and 40 millimeters, obtained without additional cutting. The second category (T2V4C2) is formed from selvedges of multiaxial fabrics, based on 600 tex fibers, with a sizing bearing the reference 2002 from PPG. This second category has an average length of approximately 25 mm, cut in a single operation. The third category (T2V4C3) is composed of fibers obtained from scraps of a composite material marketed under the reference G-PLY (the Applicant). This composite material comprises several layers of fabric based on yarns with counts of 600 and 1200 tex, bonded to a 30 g / m² glass fiber veil by stitching with a polyester binding thread. The glass fibers of this third category also bear a sizing with the commercial reference 2002 from PPG.The length of these fibers from this third fraction is approximately 25 millimeters, obtained in two successive cuts.

[0048] The third type fibers (T3V1) are derived from the recycling of composite materials. After a step of destroying the composite resin (by pyrolysis, for example), the resulting textile fraction comprises a stack of mats and NCFs, initially sewn together, and fabrics. These fibers are free of sizing, which has been destroyed by pyrolysis. The length of these fibers is approximately 25 mm, obtained through two successive cuts. Example no. 1:

[0049] The first example relates to a mat which has a weight of 50 g / m2, and which includes by weight 15% of fibers forming a binder, consisting of a mixture of polyester fibers and low-grade copolyethylene.

[0050] The remainder of the mat is therefore composed of 85% glass fibers. The three types of fibers are represented in the same proportion.

[0051] The fibers of the first type correspond to the first variety (T1V1) mentioned above.

[0052] The fibers of the second type correspond to variety no. 1 (T2V1) mentioned above. The fibers of the third type are of variety (T3V1) mentioned above.

[0053] The mat according to this example has particular aptitudes for being used for the manufacture of composite materials, as a resin support layer, or adhesion-promoting layer, or even as a support layer in association with a grid for a bituminous coating. Example #2:

[0054] A second example was made to form a mat which has a surface mass of 50 g / m2.

[0055] This mat comprises a weight of 50% copolyethylene and polyester fibers forming the binder intended to hold the glass fibers.

[0056] Glass fibers therefore represent 50% by weight. The distribution of glass fibers is balanced between fibers of the first, second and third type.

[0057] The fibers of the first type correspond to variety no. 1 (T1V1) and the fibers of the second and third types are identical to the fibers of example no. 1.

[0058] The mat according to this example has particular aptitudes for being used in applications similar to those of example no. 1. Example #3:

[0059] This example consists of a mat which has a surface mass of 116 g / m2.

[0060] This mat comprises a weight of 31% copolyethylene and polyester fibers forming the binder intended to hold the glass fibers.

[0061] Glass fibers therefore represent 69% by weight. The distribution of glass fibers is balanced between fibers of the first and second types.

[0062] The fibers of the first type correspond to the fibers of the first variety (T1V1), and the fibers of the second type are identical to the fibers of example no. 1. The mat does not contain fibers of the third type.

[0063] The mat according to this example has particular aptitudes for being used in applications similar to those of example no. 1. Example #4:

[0064] This example relates to a mat which has a weight of 150 g / m2, and which includes by weight 12% of fibers forming a binder, consisting of a mixture of polyester fibers and low-grade copolyethylene.

[0065] The rest of the mat is therefore composed of 88% glass fibers.

[0066] The fibers of the first type correspond to the second variety (T1V2) mentioned above, and represent 17% of the glass weight.

[0067] The fibers of the second type correspond to a mixture by substantially equal weight of varieties No. 1 (T2V1), No. 2 (T2V2), No. 3 (T2V3), and No. 4 (T2V4) mentioned above, representing 50% of the glass weight. The fibers of the third type are of the variety (T3V1) mentioned above and represent 33% of the glass weight.

[0068] The mast according to this example has particular properties for use in the manufacture of composite materials in the field of marine construction. Example No. 5:

[0069] This example of mat was produced, with a weight of approximately 300 g / m2.

[0070] The binder, composed of polyester and copolyethylene fibers, represents 2% of the weight of the mat.

[0071] The rest of the mat is composed of glass fibers according to the three types already mentioned.

[0072] The fibers of the first type, from the first variety (T1V1) mentioned above, represent about two-thirds of the total weight of the glass fibers of the mat.

[0073] The fibers of the second type, from the first variety (T2V1) mentioned above and of the third type each have about 17% of the weight of glass fiber of the mat.

[0074] Such a mat is particularly suitable for stacking with textile structures to form additional thicknesses, used in the manufacture of composite materials. Example #6:

[0075] This example of mat was produced, with a weight of approximately 300 g / m2.

[0076] The binder, composed of polyester and copolyethylene fibers, represents 3% of the weight of the mat.

[0077] The remainder of the mat is composed of glass fibers according to the three types already mentioned.

[0078] The fibers of the first type, from the second variety (T1V2) mentioned above, represent 17% of the total weight of the glass fibers in the mat.

[0079] The fibers of the second type correspond to a mixture by substantially equal weight of varieties No. 1 (T2V1), No. 2 (T2V2), No. 3 (T2V3) and No. 4 (T2V4) mentioned above, representing 50% of the glass weight. The fibers of the third type are of the variety (T3V1) mentioned above and represent 33% of the glass weight.

[0080] Such a mat is particularly suitable for stacking with textile structures to form additional thicknesses, used in the manufacture of composite materials. Example #7:

[0081] This example corresponds to a complex combining two layers, and has a surface mass of the order of 300 g / m2, of which 1% corresponds to the weight of the binder.

[0082] The complex comprises two layers of equal weight. A first layer, which therefore represents 50% of the total weight of glass fibers of the complex is itself made by combining glass fibers of the second variety of the first type (T1V2) at a rate of 58%, with a mixture of substantially equal weights of varieties no. 1 (T2V1), no. 2 (T2V2), no. 3 (T2V3) and no. 4 (T2V4) of the second type, at a rate of 25%, and third type (T3V1), at a rate of 17%.

[0083] The second layer corresponds to a mat made solely from fibers of the first type, from the first variety (TlVI).

[0084] The mats of the two layers are joined by sewing. Example #8:

[0085] This example corresponds to a complex combining three layers, and having a surface mass of the order of 600 g / m2, of which 1% represents the weight of the binder.

[0086] The complex comprises two outer layers and a central layer. The two outer layers are mats made from fibers of the first type, of the first variety (T1V1). Each of the outer layers represents approximately 25% by weight of the complex.

[0087] The central layer, which therefore represents 50% of the total weight of glass fibers in the complex, is itself made by combining glass fibers of the second variety of the first type (T1V2), and a mixture of substantially equal weights of varieties No. 1 (T2V1), No. 2 (T2V2), No. 3 (T2V3), and No. 4 (T2V4) of the second type. Within the central layer, the fibers of the first type represent 58% by weight of the layer. The fibers of the second type together represent 42% of the weight of glass fibers in the mass of the central layer.

[0088] The mat forming the central layer comprises a binder composed of polyester / co-polyethylene, which allows the fibers of the central layer to be bonded together. All three of these layers are joined by stitching. Example No. 9:

[0089] This example corresponds to a complex combining three layers, and having a surface mass of the order of 600 g / m2, of which 1% represents the weight of the binder.

[0090] The complex comprises two outer layers and a central layer. The two outer layers are mats made from fibers of the first type, of the second variety (T1V2). Each of the outer layers represents approximately 25% by weight of the complex.

[0091] The central layer, which therefore represents 50% of the total weight of glass fibers of the complex, is itself made by combining glass fibers of the second variety of the first type (T1V2), at 58%, a mixture with substantially equal weights of varieties no. 1 (T2V1), no. 2 (T2V2), no. 3 (T2V3) and no. 4 (T2V4) of the second type at 25% and of the third type (T3V1) at 17%.

[0092] The mat forming the central layer includes a binder composed of polyester / co-polyethylene, which allows the fibers of the central layer to be linked together. All three of these layers are joined by stitching. Example #10:

[0093] This example corresponds to a complex combining two layers, and has a surface mass of the order of 600 g / m2, of which 1% corresponds to the weight of the binder.

[0094] The complex comprises two layers of equal weight. A first layer, which therefore represents 50% of the total weight of glass fibers of the complex, is itself made by combining glass fibers of the second variety of the first type (T1V2) at a rate of 58%, a mixture of substantially equal weights of varieties no. 1 (T2V1), No. 2 (T2V2), No. 3 (T2V3) and No. 4 (T2V4) of the second type, at 25%, and third type (T3V1), at 17%.

[0095] The second layer is a mat made solely from fibers of the first type, from the first variety (TlVI).

[0096] The mats of the two layers are joined by sewing. Example no. 11:

[0097] This example corresponds to a complex combining two layers, and has a surface mass of the order of 600 g / m2, of which 1% corresponds to the weight of the binder.

[0098] The complex comprises two layers of equal weight. A first layer, which therefore represents 50% of the total weight of glass fibers of the complex is itself made by combining glass fibers of the second variety of the first type (T1V2) at a rate of 58%, with a mixture of substantially equal weights of varieties no. 1 (T2V1), no. 2 (T2V2), no. 3 (T2V3) and no. 4 (T2V4) of the second type, at a rate of 42%.

[0099] The second layer is a mat made solely from fibers of the first type, from the first variety (TlVI).

[0100] The mats of the two layers are joined by sewing. Example #12:

[0101] This example corresponds to a complex combining two layers, and has a surface mass of the order of 716 g / m2, of which 5% corresponds to the weight of the binder.

[0102] The complex comprises two layers. A first layer, which represents approximately 15% of the total weight of glass fibers of the complex, is itself made by combining glass fibers of the second variety of the first type (T1V2) at a rate of 50%, and with a mixture at substantially equal weights of varieties No. 1 (T2V1), No. 2 (T2V2), No. 3 (T2V3) and No. 4 (T2V4) of the second type, at a rate of 50%.

[0103] The second layer consists of unidirectional straight roving yarns, oriented at 0 degrees, forming a 600g / m2 layer.

[0104] The two layers are joined by sewing. Example #13:

[0105] This example corresponds to a complex combining two layers, and having a surface mass of the order of 772 g / m2, of which 1.2% corresponds to the weight of the binder.

[0106] The complex comprises two layers. A first layer corresponds to the product of example 6, which represents approximately 38% of the total weight of glass fibers of the complex.

[0107] The second layer is a complex marketed by the Applicant under the reference G-PLY BT472, having a weight of 472 g / m2.

[0108] The two layers are joined by sewing. Example #14:

[0109] This example corresponds to the complex of example no. 9, associated by stitching to a layer of non-woven material marketed by the Applicant under the reference ROVICORE PP D3, of 180 g / m2.

[0110] The two layers are joined by sewing. Example #15:

[0111] This example corresponds to the assembly of two complexes of example no. 7, between which is inserted a drainage layer of non-woven material marketed by the Applicant under the reference ROVICORE PP D3. The assembly is constructed such that the central drainage layer is in contact with the layers of the complex of example no. 6 which include fibers of the second type and that the external layers of the complex are made up of fibers of the first type, from the first variety (T1V1).

[0112] The three layers are joined by sewing. Example #16:

[0113] This example corresponds to the complex of example no. 1, associated by stitching to a complex marketed by the Applicant under the reference G-PLY TL25 600 / 298, having a weight of 898 g / m2. Example #17:

[0114] This example corresponds to the stitching of the complex of Example No. 7 and a 1500 g / m² 3-ply twill fabric made of 0-degree warp yarns from 2400 tex direct roving and weft yarns from 2400 tex direct roving. The stitching is constructed such that the fabric is in contact with the layer of the complex of Example No. 7 which includes fibers of the second type, and the outer layer of the complex of Example 7 is made of fibers of the first type, from the first variety (TlVI).

Claims

Demands

1. Non-woven textile fabric, adapted to form a permeable layer in a composite material, said fabric being made from chopped glass fibers, and incorporating means for bonding said glass fibers together, characterized in that it comprises at least two types of glass fibers, namely: - on the one hand, fibers of a first type, from chopped rovings, having a sizing of a first type; and on the other hand, fibers of at least one of the following two types, namely - fibers of a second type, from direct rovings, having a sizing of a second type, different from the sizing of the first type; - fibers of a third type, from the recycling of composite materials, free from sizing.

2. Fabric according to claim 1, characterized in that it comprises at least three types of glass fibers, namely: - fibers of a first type, from cut rovings, having a sizing of a first type; - fibers of a second type, from straight rovings, having a sizing of a second type, different from the sizing of the first type; - fibers of a third type, free from sizing

3. Fabric according to claim 1 or 2 characterized in that the majority of the fibers of the first type are gathered in a first fraction of the thickness of the fabric, the fibers of the second and / or third type being gathered in a different fraction of the thickness of the fabric.

4. Fabric according to claim 1 characterized in that the means ensuring the bonding of the glass fibers together comprise a binder formed by a powder or fibers at least partially fusible on the surface or sprayed glue droplets.

5. Fabric according to claim 1 characterized in that the means ensuring the bonding of the glass fibers together are formed by fractions of said glass fibers passing through all or part of the thickness of said fabric.

6. Fabric according to claim 1 characterized in that the average length of the first type Xi fibers is greater than the average length (X2X3) of the second and / or third type fibers.

7. Fabric according to claim 1, characterized in that the standard deviation (Oi) of fiber length of the first type is less than the standard deviation (o2 o3) of fiber length of the second and / or third type.

8. Fabric according to claim 1 characterized in that the fibers of the first type have an average length Xi between 25 and 100 millimeters.

9. Fabric according to claim 1 characterized in that the fibers of the second type have an average length X2 between 15 and 50 millimeters.

10. Fabric according to claim 1 characterized in that the fibers of the third type have an average length X3 between 15 and 50 millimeters.

11. Fabric according to claim 1, characterized in that the proportion by weight of glass fibers is: - for fibers of the first type, between 25% and 50%, - for fibers of the second and / or third type, each between 25% and 50%,

12. Fabric according to claim 1, characterized in that the proportion by weight of glass fibers is: - for fibers of the first type, between 50% and 80%, - for fibers of the second and / or third type, between 5% and 50%.

13. Fabric according to claim 1, characterized in that the proportion by weight of glass fibers is: - for fibers of the first type, between 5% and 20%, - for fibers of the second and / or third type, between 30% and 55%,

14. Fabric according to claim 4, characterized in that the at least partially fusible fibers ensuring the bonding of the glass fibers are of a material selected from the group comprising copolyesters, copolyolefins and copolyamides, taken alone or in mixture with one or more materials selected from the group comprising polyolefins, polyesters and polyamides.

15. A complex comprising a fabric according to any one of the preceding claims, characterized in that it also comprises at least one additional layer consisting of a woven fabric, a mat, a fabric based on non-waved fibers (NCF), a unidirectional yarn web, or a fabric according to any one of the preceding claims.

16. Use of the fabric or complex according to any one of claims 1 to 15, for the manufacture of a composite material including a thermosetting resin.

17. Use of the fabric or complex according to any one of claims 1 to 15 for the manufacture of bituminous or cement-based composite material.