Tire whose tread is formed entirely or partially from a unit-molded composite material

Abstract

Tire whose tread is formed entirely or partially of a unit-molded composite material. The present invention relates to a tire (10) comprising a tread (15), said tread comprising a main composite material (30) which is of unit-molded construction and which comprises a thermoplastic polymer matrix and a textile reinforcement assembly. The present invention also relates to a method for manufacturing such a tire comprising the thermocompression of a multilayer assembly including a heat-fusible textile portion and a non-heat-fusible textile portion. Figure for the abstract: Fig. 1.

Description

Title of the invention: Tire whose tread is formed entirely or partially from a unit-molded composite material. Technical field

[0001] The present invention relates to the technical field of vehicle tires, for example, bicycle tires. A tire traditionally comprises a carcass having two free longitudinal edges, each reinforced by a bead element. The carcass supports a tread intended to come into contact with the ground. On either side of the tread extend sidewalls connected to the tread.

[0002] The tire's grip on the road, its resistance to punctures and abrasion, its weight, and its ability to absorb vibrations while driving depend directly on the material it is made of. In particular, a tire's tread must meet strict requirements to ensure the comfort and safety of the vehicle user. Previous technique

[0003] The treads of conventional tires, particularly bicycle tires, are essentially made of a composite material comprising vulcanized rubber and nylon fibers. The rubber gives the tread its grip on the road and also effectively absorbs vibrations experienced by the tire tread while riding, ensuring user comfort. This composite material provides strength to the tire and guarantees good efficiency, that is, good energy return, for example, from the cyclist, under riding conditions.

[0004] One drawback of these traditional tires is that the vulcanized rubber is not easily recyclable, as it cannot be melted and its production is irreversible. The rubber in known tires, particularly bicycle tires, is commonly embedded in the composite ply, making it very difficult to extract. In particular, separating the nylon from the vulcanized rubber is challenging. Consequently, recycling traditional tires is very complex and is generally not considered due to prohibitively high processing costs. Therefore, current tires, especially bicycle tires, are destroyed after use and have a significant environmental impact. Description of the invention

[0005] One object of the present invention is to provide a tire that remedies the aforementioned disadvantages and, in particular, has a reduced environmental impact and is suitable for recycling.

[0006] To this end, the invention relates, according to a first aspect, to a tire comprising a tread characterized in that said tread comprises a main composite material which is of unit molded construction and which comprises a thermoplastic polymer matrix and a textile reinforcement assembly.

[0007] The tread is the part of the tire intended to come into contact with the ground. It preferably has a thickness of between 1 and 3 millimeters. Advantageously, the tread has a width of between 18 and 120 millimeters. The tread may have raised features to improve its grip and efficiency.

[0008] The tire advantageously comprises a carcass supporting the tread.

[0009] The tire is preferably a bicycle tire. By bicycle, we mean a vehicle of less than 100 kilograms having one, two or three wheels, for example a bicycle or a scooter.

[0010] The tire is preferably a bicycle tire.

[0011] Compared to a car tire, the tread of a bicycle tire has a reduced thickness, preferably substantially less than half the thickness of a car tire tread. Furthermore, the width of a bicycle tire tread is less, preferably between 2 and 10 times, than the width of a car tire tread.

[0012] The main composite material is understood to be a material comprising at least two components of a different nature, in particular comprising a main thermoplastic matrix and a textile reinforcement assembly, and optionally one or more non-textile elements, possibly including one or more non-textile reinforcement elements. In particular, said textile reinforcement assembly, and optionally the non-textile element(s), is / are embedded in the main thermoplastic matrix.The main composite material is preferably obtained by thermocompression of a multilayer assembly comprising a heat-fusible textile part (in particular forming a thermofused textile part within the tire) and a non-heat-fusible textile part (in particular forming a non-thermfused textile part within the tire), and optionally one or more non-heat-fusible non-textile elements (for example, a reinforcing glass fiber bead) and one or more heat-fusible non-textile elements (for example, a thermoplastic polymer film).

[0013] In one embodiment, the main composite material comprises: - one or more non-textile, non-heat-fusible element(s) (for example, a reinforcing fiberglass rod); and / or - one or more non-textile heat-fusible element(s) (for example a thermoplastic polymer film).

[0014] The term textile in this text means any element / component / tube / part / portion / structure obtained by the manipulation, in particular mechanical, of at least one fiber and / or at least one yarn, or at least a set of fibers.

[0015] Advantageously, the thermofused textile part, and possibly one or more thermofused non-textile element(s), form(s) the main thermoplastic matrix.

[0016] Advantageously, the non-heat-fusible textile part forms the textile reinforcement assembly.

[0017] Advantageously, the textile reinforcement assembly comprises one or more textile reinforcement element(s), in particular the said textile reinforcement element(s) may be chosen from: a fabric, a knit, a nonwoven (for example a spunbond nonwoven, a meltbown nonwoven, or a combination thereof), one or more yarns, a braid, a web of fibers possibly carded and / or needled, any element obtained by the manipulation of at least one yarn and / or at least one fiber, and a mixture thereof, preferably a knit, even more preferably a tubular knit. Unit molded construction means any composite material obtained by molding at least one heat-fusible textile part, and at least one non-heat-fusible textile part, and possibly at least one non-heat-fusible non-textile part (e.g., a glass fiber reinforcing rod) and / or at least one non-heat-fusible non-textile part (e.g., a thermoplastic polymer film), arranged in a molding assembly, in a single molding step comprising the application of heat and pressure to melt or soften the heat-fusible part(s).

[0018] Preferably, in the present text, the term "non-heat-fusible textile part" or "non-heat-fusible non-textile part" means any textile part, or any non-textile part, that is not intended to be heat-fused, i.e., that is not intended to be melted or softened, during the process of manufacturing a tire according to the invention, and therefore in the resulting tire.

[0019] The thermoplastic polymer matrix according to the invention may comprise one or more thermoplastic polymers, for example, of different types. The thermoplastic polymer matrix may, for example, comprise polypropylene (PP) or thermoplastic polyurethane (TPU), or a mixture thereof. Without limitation, said polymers may be of different colors.

[0020] In the present text, thermoplastic means any material capable of melting or being softened by heating for shaping, and this several times.

[0021] In particular, a thermosetting or non-thermoplastic material cannot be softened sufficiently by heating to be shaped, and this several times.

[0022] The thermoplastic polymer matrix constitutes a binding layer within which a textile reinforcement assembly is arranged, and optionally one or more non-textile, non-heat-fusible elements. The thermoplastic polymer matrix ensures the transfer of the stresses experienced by the tread to the textile reinforcement assembly.

[0023] Advantageously, in the present text, non-thermally fused means any element / component / portion / structure or any part which is not configured to be in a thermofused state in the tire, such element / component / structure or part may be partially or totally thermoplastic, preferably is thermoplastic, but the highest heating temperature applied in the tire manufacturing process according to the invention is lower than the melting temperature of said element / component / structure or said part.

[0024] Preferably, the thermoplastic polymer matrix comprises one or more fused thermo-fusible textile element(s), even more preferably consists essentially of one or more fused thermo-fusible textile(s).

[0025] Preferably, at least 50% by mass or at least 60% by mass or at least 70% by mass or at least 80% by mass or at least 90% by mass or at least about 95% by mass of the thermoplastic matrix is ​​formed of one or more melted hot melt textile element(s) and / or one or more melted hot melt film(s). The tread preferably includes one or more reinforcing elements, including at least one textile reinforcing element.

[0026] The textile reinforcement element is advantageously a non-heat-fusible textile part.

[0027] Preferably, but not limitingly, the tread has an inner face and the textile reinforcement element is located on said inner face of the tread.

[0028] Preferably, the textile reinforcement element comprises one or more yarn(s). Even more preferably, the textile reinforcement element comprises one or more knitted yarn(s).

[0029] Preferably, the textile reinforcement assembly comprises one or more textile reinforcement element(s) which is / are each a knitted tubular element, more preferably said knitted tubular element comprises picked stitches (also referred to in the prior art as weft knit) or warp stitches (also referred to in the prior art as warp knit).

[0030] Preferably, said knitted tubular element is knitted on a circular knitting machine, in particular a small diameter so-called sock knitting machine, or a straight knitting machine with a double bed.

[0031] Said at least one textile reinforcement element provides the tread with significant strength, in particular resistance to abrasion and shear stresses experienced by the tread during rolling. Said at least one textile reinforcement element also ensures the tread's adhesion to the surface, in particular the ground, on which said tread rolls.

[0032] The tire according to the invention therefore has technical properties, in particular properties of grip on the ground, resistance to abrasion and shear stress, shock and vibration absorption, similar to those of a traditional tire made of vulcanized rubber.

[0033] The tire according to the invention has a weight substantially similar to that of a traditional tire of the same dimensions, but made of a composite material based on vulcanized rubber and nylon. In other words, the use of a main composite material comprising a thermoplastic polymer matrix and at least one textile reinforcement element according to the invention does not significantly increase the weight of the tread and therefore of the tire.

[0034] The main composite material forming at least in part the tread of the tire according to the invention also gives the latter a recyclability much higher than that of traditional tires whose tread is made of vulcanized rubber and nylon.

[0035] Indeed, since the polymer matrix is ​​thermoplastic, it can be softened or melted by heating it to a temperature above a threshold temperature, for example, its melting point. The manufacturing of the polymer matrix is ​​therefore reversible and allows for the recycling of said thermoplastic polymer matrix. In other words, by heating the tire, possibly after shredding, it is possible to recycle the thermoplastic polymer matrix in combination with the textile reinforcement assembly to produce new tires or one or more tire components, for example. Furthermore, the thermoplastic polymer material forming the thermoplastic polymer matrix and the textile reinforcement assembly can easily be separated from each other by heating the tread.

[0036] Furthermore, since the reinforcement assembly is textile, it is also particularly recyclable. Therefore, the entire composite material is particularly recyclable, so the portion of the tread formed by the main composite material can be easily recycled.

[0037] The tire according to the invention is therefore highly recyclable and its environmental impact is greatly reduced.

[0038] The tread is preferably made essentially of the main composite material so as to be substantially fully recyclable.

[0039] In a preferred embodiment, the main composite material of unit molded construction consists essentially of a thermoplastic polymer matrix, and a set of textile reinforcement, in particular at least one textile reinforcement element, and optionally one or more non-textile element(s).

[0040] Preferably, in the present text, the main composite material is understood to consist essentially of a thermoplastic polymer matrix and a textile reinforcement assembly, that the thermoplastic polymer matrix and said textile reinforcement assembly, considered together, constitute the majority by mass or volume in said main composite material, preferably that said thermoplastic matrix and said textile reinforcement assembly represent at least 50% by mass or volume, and even more preferably at least 60% or at least 70% or at least 80% or at least 90% or at least 95% by mass or volume, of the main composite material.

[0041] In a preferred embodiment, the main composite material represents at least 60% by volume or mass, preferably at least 70% by volume or mass, even more preferably at least 80% by volume or mass, preferably at least 90% by volume or mass, in particular at least 95% by volume or mass, more particularly about 100% by volume or mass, of the tread.

[0042] The main composite material preferably comprises one or more reinforcing elements, including one or more textile reinforcing elements. In other words, without departing from the scope of the invention, the main composite material may comprise one or more reinforcing elements that are not textile.

[0043] Without departing from the scope of the invention, the thermoplastic polymer matrix may comprise one or more thermoplastic (co)(ter)polymer(s) selected from: polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, polyurethanes, polyamides, polyesters, and a mixture of the latter, preferably polyurethanes.

[0044] Advantageously, the polyolefins are selected from: polypropylene, polyethylene, high-density polyethylene, very high-density polyethylene.

[0045] Advantageously, styrenic thermoplastic elastomers are selected from thermoplastic elastomers comprising styrenic repeating motifs (TPE-S) (in particular a styrene group: -CH(C6H5)-CH2), or preferably from thermoplastic elastomers comprising one or more styrenic block(s) and optionally one or more olefin block(s) (possibly grafted), preferably from poly(styrene-ethylene-butylene-styrene) (SEBS); poly(styrene-butadiene-styrene) (SBS); poly(styrene-butadiene) (SBC); poly(styrene-isoprene-styrene) (SIS); poly(styrene-ethylene-propylene-styrene) (SEPS), for example marketed under the brand name Septon SEPS® by the company Kuraray, or Kraton G® by the company Kraton.

[0046] Advantageously, olefinic thermoplastic elastomers are selected from: - polyisobutylenes (PIB); and / or - ethylene, propylene, and diene terpolymers (EPDM); ethylene and propylene copolymers; ethylene and alpha-olefin copolymers, for example ethylene and butene copolymers or ethylene and octene copolymers, and a mixture thereof; preferably EPDM and ethylene and propylene copolymers; and / or - mixtures of a polyolefin, in particular polypropylene, with one or more non-vulcanized olefinic thermoplastic elastomer(s), and possibly one or more plasticizers (for example mineral or naphthenic or paraffinic oil(s)), the said olefinic thermoplastic elastomer(s) may be copolymers of ethylene and propylene, terpolymers of ethylene, propylene and diene, copolymers of ethylene and alpha-olefin(s) (for example ethylene and butene copolymers or ethylene and octene copolymers).

[0047] Advantageously, the polyesters are chosen from polyethylene terephthalate and polybutylene terephthalate.

[0048] Advantageously, the polyamides are chosen from PA 6, PA 66, PA 4-6.

[0049] Advantageously, polyurethanes also include polyurethane elastomers.

[0050] Advantageously, the thermoplastic polymer matrix consists essentially of one or more thermofused polymer(s). "Constituted essentially" means that the thermofused polymer(s) represent(s) at least 80% by mass, preferably at least 90% by mass, and even more preferably about 100% by mass, of the thermoplastic polymer matrix.

[0051] In one embodiment, the main composite material forms at least 80% by mass of the tread. Preferably, the main composite material forms at least 90% by mass, in particular at least 95% by mass, and more particularly about 100% by mass, of the tread. One advantage is that the tread is formed predominantly, and more particularly entirely, of a recyclable material, thus improving the recyclability of the tire and further reducing its environmental impact.

[0052] In one embodiment, the textile reinforcement assembly comprises at least two textile layers.

[0053] By way of non-limitation, a first layer may be heat-fusible while the second layer is not. Alternatively, each of the two textile layers may be partly heat-fusible, and optionally each of the two layers may include a non-heat-fusible portion.

[0054] In one embodiment, the main composite material comprises at least a first textile layer, a second textile layer, a third textile layer and a fourth textile layer.

[0055] Preferably, at least one of said textile layers is partly heat-fusible. Preferably, at least one of said textile layers has a heat-fusible part and a non-heat-fusible part.

[0056] Alternatively, and without departing from the scope of the invention, one or more of said textile layers could be entirely heat-fusible while the other textile layer(s) is / are not heat-fusible.

[0057] The presence of these four textile layers improves the fit and resistance of the tire.

[0058] By way of non-limitation, the main composite material may further comprise a fifth textile layer and a sixth textile layer.

[0059] In one embodiment, each of said textile layers comprises at least one heat-fusible part, and at least one non-heat-fusible part.

[0060] In one embodiment, said textile reinforcement assembly comprises a first portion of textile tube, the first portion of textile tube comprising said first and second textile layers, and said textile reinforcement assembly further comprises a second portion of textile tube, the second portion of tube comprising said third and fourth textile layers.

[0061] One advantage is that the manufacture of each portion of the tube makes it possible to create two textile layers, which facilitates the manufacturing process, in particular by avoiding errors in superimposing the layers on each other.

[0062] In one embodiment, said textile reinforcement assembly comprises a first portion of knitted, woven or braided tube, the first portion of tube comprising said first and second textile layers, and said textile reinforcement assembly further comprises a second portion of knitted, woven or braided tube, the second portion of tube comprising said third and fourth textile layers.

[0063] Advantageously, the first portion of the textile tube is flattened so that two superimposed textile layers are obtained, formed by the first and second textile layers. Preferably, the second portion of the textile tube is flattened so that two superimposed textile layers are obtained, formed by the third and fourth textile layers.

[0064] Without limitation, the first and second portions of the tube may be distinct from each other.

[0065] Preferably, at least one of the first and second tube portions is knitted in the round on a circular knitting machine, in particular of small diameter, or on a straight knitting machine comprising two needle beds.

[0066] By way of exception, the first tube portion can be obtained by knitting a strip whose longitudinal edges are joined, for example by a longitudinal seam. Alternatively, and preferably, the first textile tube portion can be knitted in a circular fashion, in which case it is not necessary to close said first tube portion longitudinally.

[0067] In one embodiment, said first and second tube portions are arranged one above the other or arranged one inside the other.

[0068] One advantage is the ability to position the four layers more easily and more precisely in relation to each other and, in addition, to be able to achieve more precise "zoning" on the tread.

[0069] In the present text, zoning means any modification of at least one textile parameter in one or more region(s) of the tubular textile portion, in particular knitted, said at least one parameter being chosen from: the type of yarn (composition, fineness, partially or fully heat-fusible, color, transparency) and the bonding point (mesh pattern).

[0070] In the embodiment where the first and second tube portions are arranged one above the other, the first and second textile layers are successive textile layers while the third and fourth textile layers are successive textile layers.

[0071] In the embodiment where the first and second tube sections are arranged one inside the other, the second tube section is preferably arranged inside the first tube section. In this case, the third and fourth textile layers extend between the first and second textile layers. The first and second tube sections are substantially coaxial.

[0072] Alternatively, and without limitation, the first tube portion may be arranged inside the second tube portion, in which case the first and second textile layers extend between the third and fourth textile layers.

[0073] In one embodiment, said textile reinforcement assembly comprises a first textile reinforcement element including a first textile zone and a second textile zone connected to the first textile zone, in particular by knitting, said first textile zone differing from said second textile zone by at least one property selected from: the mesh pattern (for example, presence of looped meshes of the sponge type or woven floats or lines of meshes inclined with respect to the longitudinal axis of the first textile reinforcement element), the number of yarn(s), the nature of the yarn(s), the mass fraction of the thermofused textile part (in particular the mass fraction of the heat-fusible textile part), the mass fraction of the non-heat-fusible textile part (in particular the mass fraction of the non-heat-fusible textile part) or the fineness (dtex) of the yarn(s).

[0074] Advantageously, the first knitted zone differs from the second knitted zone by at least one property which will impact, for example, the mechanical behavior.

[0075] For example, the first knitted area includes an elastic yarn while the second knitted area does not include an elastic yarn.

[0076] For example, the second knitted zone comprises a mass proportion of yarn(s) at least partly hot-meltable than the mass proportion of yarn(s) at least partly hot-meltable in the first knitted zone.

[0077] In one embodiment, the first and second textile layers are in a first textile element of unitary textile construction reinforcement, and the third and fourth textile layers are in a second textile element of unitary textile construction reinforcement.

[0078] The first, third, and second, fourth textile layers are understood to be of unitary textile construction, meaning that they are joined textiles, particularly knitted textiles, and in particular that they are in a single piece of textile obtained from a textile machine, especially a knitting machine, more particularly without any additional steps in its manufacture other than the finishing of its edges and / or the embroidery of at least one elongated element. This definition advantageously applies to any layer / element / piece of textile of unitary textile construction.

[0079] In other words, the first and second textile layers are in the same piece of textile. The first and second textile layers are connected to each other by at least one knitted or woven yarn in both the first and second textile layers. Similarly, the third and fourth textile layers are in the same piece of textile. The third and fourth textile layers are connected to each other by at least one knitted or woven yarn in both the first and second textile layers.

[0080] Without limitation, said first and second layers may be successive layers, for example superimposed layers, or layers distant from each other, separated by other layers.

[0081] Preferably, said first, second, third and fourth textile layers are superimposed at least partially on one another.

[0082] In one embodiment, the first, second, third and fourth textile layers are in a first textile reinforcement element of unitary textile construction.

[0083] Preferably, the main composite material comprises a tube including said first and second tube portions. In a first embodiment, the tube is folded back on itself so that the first and second tube sections are arranged one above the other. In this embodiment, the first and second tube sections are connected to each other by a fold.

[0084] In another embodiment, said tube is folded back on itself so as to have the second portion of the tube inside the first portion of the tube.

[0085] In one embodiment, the main composite material comprises at least one intermediate thermoplastic polymer layer, said intermediate thermoplastic polymer layer being disposed between two adjacent textile layers.

[0086] Said intermediate thermoplastic polymer layer is configured to partially form the thermoplastic polymer matrix. This intermediate thermoplastic polymer layer improves the impermeability and puncture resistance of the tread.

[0087] The intermediate thermoplastic polymer layer advantageously has the form of a thermofused polymer sheet (in particular hot-melt before its thermocompression).

[0088] Advantageously, an intermediate thermoplastic polymer layer can be disposed between two superimposed tube portions, and / or between the first and second textile layers, and / or between the third and fourth textile layers, and / or between the first and third textile layers (when the first and second tube portions are coaxial), and / or between the fourth and second textile layers (when the first and second tube portions are coaxial).

[0089] In one embodiment, the main composite material comprises at least one external thermoplastic polymer layer, said external thermoplastic polymer layer being disposed in an external part of the tread intended to come into contact with the ground. The outer thermoplastic polymer layer is intended to come into contact with the ground. This outer thermoplastic polymer layer forms a wear layer for the tread.

[0090] Said external thermoplastic polymer sheet improves the adhesion of the tread to the ground as well as the abrasion resistance of the tread.

[0091] The external thermoplastic polymer layer advantageously has the form of a thermofused polymer sheet at least in part or entirely.

[0092] In one embodiment, the mass fraction of thermoplastic material(s) in the main composite material is greater than or equal to 80%, preferably greater than or equal to 90%, even more preferably greater than or equal to 95%, in particular about 100%.

[0093] This feature promotes the tire's recyclability. Indeed, thermoplastic materials can be reshaped multiple times by heating.

[0094] In one embodiment, the mass fraction of the thermoplastic polymer matrix in the main composite material is greater than or equal to 50%, preferably greater than or equal to 60%, more preferably greater than or equal to 70%, more preferably greater than or equal to 80%.

[0095] In one embodiment, the mass fraction of the thermoplastic polymer matrix in the main composite material is less than or equal to 90%, preferably less than or equal to 85%. The mass fraction of the polymer matrix in the main composite material is understood to be the ratio of the total mass of the polymer(s) (in particular thermofused) forming the thermoplastic polymer matrix to the total mass of the main composite material of unit molded construction.

[0096] In one embodiment, the mass fraction of the textile reinforcement assembly, in particular in textile reinforcement element(s), in the composite material is less than or equal to 50%, preferably less than or equal to 40%, in particular less than or equal to 30%, preferably greater than or equal to 5% and less than or equal to 20%, again preferably greater than or equal to 10% and less than or equal to 15%.

[0097] In one embodiment, the thermoplastic polymer matrix comprises polyurethane, in particular comprises predominantly polyurethane by mass.

[0098] In one embodiment, the mass fraction of polyurethane(s) in the main composite material is greater than or equal to 5%, preferably greater than or equal to 10%, even more preferably greater than or equal to 20%, preferably greater than or equal to 30%, in particular greater than or equal to 40%, more particularly greater than or equal to 50%.

[0099] In one embodiment, the mass fraction of polyurethane(s) in the main composite material is less than or equal to 90%, preferably less than or equal to 80%, more preferably less than or equal to 70%.

[0100] In one embodiment, the main composite material, preferably the thermoplastic polymer matrix, comprises a first part including a first aesthetic property chosen from a first color and a first design, and a second part including a second aesthetic property chosen from a second color and a second design, the first aesthetic property being different from the second aesthetic property.

[0101] Preferably the first and second colours are not black.

[0102] Patterns and inscription(s) can therefore be formed on the tread.

[0103] Preferably, the tread comprises a plurality of substantially similar patterns spaced according to the length of the tread.

[0104] Preferably, the main composite material, preferably the thermoplastic polymer matrix, comprises a first portion including a first relief, and a second portion including a second relief different from the first relief.

[0105] Said first and second reliefs are advantageously independent of the color of the thermoplastic polymer matrix.

[0106] Preferably, the main composite material comprises a first textile reinforcement element in a first color and a second textile reinforcement element in a second color, the second color being different from the first color.

[0107] In one embodiment, the main composite material, preferably the thermoplastic polymer matrix, includes a transparent or translucent part forming a viewing window through which at least a portion of the textile reinforcement assembly is visible from outside the tire.

[0108] In one embodiment, the main composite material, preferably the thermoplastic polymer matrix, comprises at least one light-reflecting design.

[0109] In one embodiment, said textile reinforcement assembly comprises one or more yarns comprising at least one material selected from: polyesters; in particular high-tenacity polyesters; polyamides; aramids; polyolefins; celluloses; glass, or a mixture thereof.

[0110] In one embodiment, said at least one textile reinforcement assembly comprises, in particular the textile reinforcement element(s) comprises (each), one or more yarn(s) in at least one material selected from: polyesters; in particular high-tenacity polyesters; polyamides; aramids; polyolefins; glasses, or a mixture thereof.

[0111] Advantageously, the polyesters can be chosen from polyethylene terephthalate (PET), and polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), or a mixture of the latter, preferably polyethylene terephthalate PET.

[0112] Advantageously, the polyolefins can be selected from polypropylene, polyethylene, a copolymer of ethylene and propylene, high-density polyethylene (such as PEUHMW), preferably polypropylene and polyethylene.

[0113] Advantageously, the polyamides can be selected from: PA 6, PA 6-6, PA 4-6, PA 11 or 12, or a mixture of the latter, preferably PA 6 or PA 6-6.

[0114] Advantageously, aramids are selected from meta-aramids and para-aramids. Aramids are not preferred in the context of the present invention because they are not thermoplastic.

[0115] Preferably, said textile reinforcement assembly comprises one or more textile reinforcement element(s) comprising, in particular, made up of, (each) one or more yarn(s) selected from the preceding list.

[0116] Preferably, said textile reinforcement assembly comprises several yarns, said yarns being of the same nature or of different natures.

[0117] In one embodiment, the main composite material comprises one or more wire(s) at least partially thermally melted.

[0118] In the present text, the said wire(s) at least partly heat-melted may be (each) entirely melted or partially melted.

[0119] The said wire(s) at least partly thermally melted is / are a wire(s) at least partly thermally fused before being transformed in the process of manufacturing a tire according to the invention, in particular described below according to a second aspect of the invention.

[0120] In this text, the said wire(s) at least partly fusible can / can be (each) entirely fusible or partially fusible.

[0121] A wire that is at least partially thermally fused may be a core-mantle type wire. Preferably, a core-mantle type wire comprises a core having a melting or softening temperature T1, and a mantle having a melting or softening temperature T2, where T1 is greater than T2. ​​Advantageously, the mantle is configured to melt / soften at a temperature T2 that is lower than the core's melting / softening temperature T1 during tire manufacturing.

[0122] A wire at least partly thermally melted can be a side-by-side type wire, a first side is formed of a material having the melting or softening temperature T1 as defined above, and a second side is formed of a material having the melting or softening temperature T2 as defined above.

[0123] In particular, the first side and the second side are arranged longitudinally along the length of the wire.

[0124] Therefore, in the main composite material, the coat or second side of such a yarn is melted into the thermoplastic polymer matrix while the core or first side forms at least in part the textile reinforcement element.

[0125] A wire at least partly thermally melted can be a wire entirely made of a thermofusible material, that is to say having a melting or softening temperature lower than the thermocompression temperature used for the manufacture of the tire according to the invention.

[0126] In this case, the fully heat-fusible wire forms at least in part the thermoplastic polymer matrix of the main composite material.

[0127] In one embodiment, the main composite material includes, in particular the textile reinforcement element(s) includes (each), one or more yarn(s) not heat-fused at least in part.

[0128] Advantageously, the wire(s) at least partly not thermally melted can / can be (each) entirely not thermally melted or partially thermally melted.

[0129] Advantageously, the non-thermally melted part of a non-thermally melted yarn at least in part forms a textile reinforcing yarn, that is to say a longline textile reinforcing element.

[0130] Advantageously, the textile reinforcement assembly comprises one or more tubular knit(s) comprising (each) one or more partially non-thermally melted yarn(s) and / or one or more non-thermally melted yarn(s).

[0131] In one embodiment, the main composite material comprises one or more core-coat type yarn(s) comprising (each) a metallic core and a coat comprising at least one thermoplastic polymer material, in particular thermofused (in particular hot-melt in the tire manufacturing process), for example polyurethane.

[0132] This arrangement significantly improves the tire's resistance. Another advantage is that the metal core can be easily extracted from the used tire and recovered separately from the rest of the tire before the tire is recycled. This facilitates the recycling of the remaining tire.

[0133] In one embodiment, the tread, in particular at least one textile reinforcement element, comprises at least one knitted pattern, for example chevrons. Preferably, the knitted patterns extend along a longitudinal direction (Lbr) of the tread, in particular of said knitted reinforcement element, and repeatedly over a portion of the length of the tread or of said knitted reinforcement element, or over the entire length of the tread or of said knitted reinforcement element.

[0134] The knitted patterns may also extend into a first flank and / or a second flank (as described below). In this case, preferably, the tread and the first flank, and possibly the second flank, are each formed at least in part from the main composite material.

[0135] In one embodiment, the tread comprises a longitudinal direction Lbr, and the main composite material, in particular at least one textile reinforcement element, comprises knitted meshes arranged along knitted mesh lines and comprising one or more reinforcing yarn(s), at least one of said mesh lines knitted having a longitudinal direction Lmt, the direction Lmt being secant with the longitudinal direction Lbr.

[0136] Advantageously, the main composite material, in particular said at least one textile reinforcement element, comprises a longitudinal direction Lmc substantially parallel to the longitudinal direction Lbr of the tread.

[0137] Advantageously, the longitudinal direction Lbr of the tread, respectively the longitudinal direction Lmc of the main composite material, extends along the general circumferential direction of the tire.

[0138] Advantageously, the longitudinal direction Lmt forms with the longitudinal direction Lbr an angle [31 greater than 0° and less than or equal to 90°, in particular less than or equal to 60°, more particularly less than or equal to 50°.

[0139] Advantageously, [31 is greater than or equal to 10°, in particular greater than or equal to 20°, more particularly greater than or equal to 30°.

[0140] Said knitted meshes arranged along rows of knitted meshes may also extend into a first flank and / or a second flank (as described below). In this case, preferably, the tread and the first flank, and possibly the second flank, are each formed at least in part from the main composite material.

[0141] In one embodiment, said tire further comprises at least one sidewall, and said main composite material forms at least part of said at least one sidewall. One advantage is also to improve the recyclability of the sidewall and thus more generally of the tire.

[0142] Said sidewall and said tread are preferably of unit molded construction.

[0143] The tire preferably comprises a first sidewall and a second sidewall, said sidewalls extending on either side of the tread.

[0144] Preferably, the main composite material forms at least partly the first sidewall, and at least partly the second sidewall, even more preferably the main composite material forms the first and second sidewalls and the tread.

[0145] The first and second sidewalls and said tread are preferably of unit molded construction.

[0146] Preferably, the tread and the sidewall include at least one yarn in common, preferably a knitted yarn.

[0147] In one embodiment, the mass fraction of the textile reinforcement assembly in the tread is greater, in particular by at least two or three times, than the mass fraction of the textile reinforcement assembly in said at least one sidewall. One advantage is to improve the strength, particularly the abrasion and impact resistance, of the tread while reducing the tire weight. Indeed, the sidewalls are not not or only minimally intended to come into contact with the ground, so they are less subject to adhesion and abrasion resistance requirements.

[0148] By mass fraction (%) of the textile reinforcement assembly in the tread, respectively a sidewall, is understood the ratio of the total mass of the textile reinforcement assembly in said tread, respectively said sidewall, to the total mass of the tread, respectively said sidewall, in particular this mass fraction can be calculated over a portion of the length of the tire or over the entire tire.

[0149] In one embodiment, the mass fraction of the textile reinforcement assembly in at least one flank, in particular the first flank and / or the second flank, is greater than or equal to 20%, preferably greater than or equal to 30%, even more preferably greater than or equal to 40%, preferably less than or equal to 80%, in particular less than or equal to 70% or 60%.

[0150] In one embodiment, the mass fraction of the textile reinforcement assembly in the tread is less than or equal to 45%, in particular less than or equal to 30%, more particularly less than or equal to 20%.

[0151] In one embodiment, the mass fraction of the thermoplastic polymer matrix in the tread is greater, in particular by at least two or three times, than the mass fraction of thermoplastic polymer matrix in a sidewall, in particular a first or second sidewall.

[0152] Advantageously, a sidewall has the function of allowing the tire to be attached to a wheel, and does not come into direct contact with the ground so that less textile reinforcement is needed.

[0153] Advantageously, it is possible in the present invention to adjust the mass fraction of thermoplastic polymer matrix and the mass fraction of textile reinforcement independently of each other in the tire, in particular between the tread and at least one sidewall, by varying the mass fractions of thermofused textile portion(s) and non-thermfused textile portion(s).

[0154] In one embodiment, the mass fraction of the thermoplastic polymer matrix in the tread is greater than or equal to 30%, preferably greater than or equal to 50%, even more preferably greater than or equal to 60%.

[0155] In one embodiment, the mass fraction of the thermoplastic polymer matrix in said at least one flank, in particular in the first flank and / or the second flank, is greater than or equal to 5%, preferably greater than or equal to 20%, more preferably greater than or equal to 30%, in particular less than or equal to 60%.

[0156] In one embodiment, the tread comprises at least one ERBR textile reinforcement element, and said at least one sidewall comprises at least one ERPF textile reinforcement element different from said ERBR textile reinforcement element of the tread.

[0157] The ERPF textile reinforcement element advantageously has a different linear mass, in particular two to three times lower, than the linear mass of the ERBR textile reinforcement element.

[0158] The ERBR textile reinforcement element and the ERPF textile reinforcement element preferably comprise (or are) one or more yarns of a different nature. For example, the ERBR textile reinforcement element may comprise (or be) one or more polyamide yarns, while the ERPF textile reinforcement element comprises (or is) one or more polyester yarns.

[0159] In one embodiment, the surface mass (g / m²) of said at least one sidewall is less than the surface mass (g / m²) of the tread. One advantage is to increase the puncture resistance of the tread while limiting the weight of the sidewall and therefore of the tire.

[0160] In one embodiment, the mass fraction of textile reinforcement(s) in said at least one sidewall is greater than the mass fraction of textile reinforcement(s) in said tread.

[0161] In one embodiment, said tire comprises two free longitudinal edges left and right, at least one of said two free longitudinal edges left and right comprises a bead element, and said main composite material forms at least in part said bead element.

[0162] In one embodiment, the thermoplastic polymer matrix forms at least 50% by volume or mass of said rod element, in particular at least 80% by volume or mass of said rod element.

[0163] One advantage is to further improve the recyclability of the tire compared to traditional tires whose beads are metallic and must be removed before the tire can be recycled. Furthermore, it is understood that the beads and tread are in a single molded construction, thus simplifying tire manufacturing.

[0164] In one embodiment, the tire comprises at most 10% by mass of vulcanized rubber(s) and / or one or more thermosetting polymer(s), possibly vulcanized. One advantage is to reduce the amount of material that is difficult or impossible to recycle within the tire, thereby further improving the tire's recyclability.

[0165] Preferably, the tire comprises at most 5% by mass of vulcanized rubber(s) and / or one or more thermosetting polymer(s), possibly vulcanized.

[0166] Preferably, the tread and / or the main composite material and / or the tire does not include vulcanized rubber(s) and / or thermosetting polymer(s), possibly vulcanized.

[0167] Where the tread and / or the main composite material and / or the tire comprises one or more vulcanized rubbers and / or one or more thermosetting polymers, possibly vulcanized, this or these represent at most 10% by mass of the total mass of the tire, in particular at most 5% by mass of the total mass of the tire.

[0168] In one embodiment, the tread comprises at least 50%, preferably at least 60%, even more preferably at least 70%, preferably at least 80%, by mass of polyurethane(s), in particular thermoplastic polyurethane(s).

[0169] In one embodiment, at least 50% by mass, preferably at least 60% or 70% or 80% by mass, of the thermoplastic polymer matrix of the main composite material is made up of one or more thermoplastic polyurethane(s), and optionally said main composite material includes one or more textile reinforcement element(s), in particular non-thermally melted, based on polyurethane(s).

[0170] The present invention also relates, according to a second aspect, to a method for manufacturing at least a part of a tire, in particular a tire, notably as described above with reference to the first aspect of the invention, comprising the steps of: a) prepare a multilayer assembly comprising at least one heat-fusible textile part and at least one non-heat-fusible textile part; b) thermo-compress said multi-layer assembly with a mold configured to mold the tread of a tire, by heating said multi-layer assembly so as to melt said thermofusible textile part; (c) Obtaining a primary composite material for unit molded construction comprising a thermoplastic polymer matrix and a textile reinforcement assembly, said composite material forming at least in part the tread of a tire. Thermocompression causes the melting and / or softening of the heat-fusible textile portion of the multilayer assembly, such that the heat-fusible textile portion melted by thermocompression forms at least in part the thermoplastic polymer matrix of the resulting composite material. The non-heat-fusible textile portion does not melt during thermocompression, so that said non-heat-fusible textile portion forms at least in part the textile reinforcement assembly of the resulting primary composite material.

[0171] Preferably, the multilayer assembly includes at least a first textile layer that is partly heat-fusible.

[0172] The multilayer assembly results from the implementation of elements (possibly a polymer film or metallic thread, for example) and / or solid textile layer(s). No liquid resins or solvents are used.

[0173] In one embodiment, step a) includes preparing a multilayer assembly comprising a first textile layer comprising at least one yarn A which is at least partly heat-fusible, a second textile layer comprising at least one yarn B which is at least partly heat-fusible, a third textile layer comprising at least one yarn C which is at least partly heat-fusible and a fourth textile layer comprising at least one yarn D which is at least partly heat-fusible; and step b) includes thermocompression of the multilayer assembly with a mold configured to mold at least the tread of a tire, by heating said multilayer assembly so as to melt at least partly said yarns A, B, C and D, of said first, second, third and fourth textile layers.

[0174] The molten portion from yarns A and / or B and / or C and / or D forms, at least in part or in whole, the thermoplastic polymer matrix of the main composite material, while the unmolded portion from yarns A and / or B and / or C and / or D forms, at least in part or in whole, the textile reinforcement assembly of said main composite material.

[0175] A layer A, or B, or C, or D, is advantageously at least partly thermofusible, that is to say that it can be entirely thermofusible (and therefore thermomelted / softened during step b) in the main composite material) or partially thermofusible (and therefore thermomelted / softened during step b) partially in the main composite material).

[0176] Advantageously, the multilayer assembly has a general strip shape comprising two free ends or ends joined together to form a torus, for example the free ends are joined together by a seam.

[0177] Advantageously, the multilayer assembly has a strip-like shape and has first and second free ends between which the longitudinal direction of said multilayer assembly extends, and a first lateral edge and a second lateral edge between which the transverse direction of said multilayer assembly extends. Advantageously, the transverse direction of said multilayer assembly is substantially perpendicular to the longitudinal direction of said multilayer assembly.

[0178] Advantageously, the length of the strip-shaped multilayer assembly corresponds to the distance between the first and second free ends of the multilayer assembly.

[0179] Advantageously, the width of the multilayered strip-shaped assembly corresponds to the distance between the first and second lateral edges.

[0180] Advantageously, the longitudinal direction of the multilayer assembly extends along the general circumferential direction of the tire (or torus).

[0181] Said textile layer may also include a textile portion that is thermoplastic and therefore intrinsically thermofusible but is not intended to be thermomelted / softened during step b) of thermocompression. This type of textile material is not considered thermofusible within the scope of the present invention.

[0182] In one embodiment, the non-heat-fusible textile portion comprises a first polyurethane having a melting or softening temperature T3, and the heat-fusible textile portion comprises a second polyurethane having a melting or softening temperature T4, T3 being higher than T4. The first polyurethane provides the tread with stiffening properties and improves the tread's resistance, particularly to punctures, abrasion, and deformation. Once melted, the second polyurethane binds the textile reinforcement element(s) comprising the textile reinforcement assembly within the thermoplastic polymer matrix, providing cohesion between these reinforcement elements.

[0183] In one embodiment, the multilayer assembly includes at least one textile reinforcement element comprising knitted loops or woven floats comprising one or more yarns at least partly heat-fusible.

[0184] In one embodiment, the multilayer assembly is configured so as to obtain in step c) a main composite material also forming at least part of a sidewall of the tire.

[0185] In one embodiment, the first and second textile layers are in a first unitary textile construction element and the third and fourth textile layers are in a second unitary textile construction element.

[0186] Advantageously, the multilayer assembly comprises a first unitary textile construction element, said first textile element comprising said first and second textile layers, and a second unitary textile construction element, said second textile element comprising said third and fourth textile layers.

[0187] In one embodiment, the main composite material comprises a first portion of knitted, woven or braided tube, the first portion of tube comprising said first and second textile layers, and the main composite material further comprises a second portion of knitted, woven or braided tube, the second portion of tube comprising said third and fourth textile layers.

[0188] In one embodiment, the multilayer assembly is heated to a temperature greater than or equal to 100°C and less than or equal to 250°C.

[0189] In one embodiment, the multilayer assembly comprises at least one textile reinforcement element, said textile reinforcement element comprising at least one knitted pattern, for example, chevrons. Preferably, the knitted patterns extend along the longitudinal direction of the multilayer assembly, in particular in the general form of a band, and are repeated over a portion of the length of said knitted reinforcement element, or over the entire length of said knitted reinforcement element.

[0190] The knitted patterns may also extend over part of the width of said knitted reinforcement element, or over the entire width of said knitted reinforcement element.

[0191] Advantageously, the V-patterns, or chevrons, comprise first V-patterns and second V-patterns knitted or woven with one or more yarns different from the yarn(s) of the first V-patterns. The first V-patterns are alternated with the second V-patterns over at least part of the length of the multilayer assembly.

[0192] Advantageously, at least a first V-shaped or chevron pattern comprises a mass fraction of heat-fusible textile greater than the mass fraction of heat-fusible textile of at least a second V-shaped or chevron pattern.

[0193] In one variant, the multilayer assembly comprises at least one textile reinforcement element comprising knitted meshes with one or more reinforcing yarn(s), in particular non-heat-fusible yarn(s) at least in part, said knitted meshes being arranged along rows of knitted meshes, at least one of said rows of knitted meshes having a longitudinal direction Lmt, the direction Lmt being secant with the longitudinal direction of the multilayer assembly.

[0194] Advantageously, the knitted stitch lines include knitted stitch lines inclined towards the first lateral edge or the second lateral edge.

[0195] Advantageously, the longitudinal direction Lmt forms with the longitudinal direction of the multilayer assembly an angle [31 greater than 0° and less than or equal to 90°, in particular less than or equal to 60°, more particularly less than or equal to 50°.

[0196] Advantageously, [31 is greater than or equal to 10°, in particular greater than or equal to 20°, more particularly greater than or equal to 30°.

[0197] The knitted mesh lines may also extend over part of the width of said knitted reinforcement element, or over the entire width of said knitted reinforcement element.

[0198] In one variant, the multilayer assembly forms at least 80% by mass or volume, preferably at least 90% by mass or volume, more preferably about 100% by mass or volume, of the tread, in particular of the tread with a first flank and / or a second flank.

[0199] The present invention also relates, according to a third aspect, to a method for recycling a tire, advantageously comprising: - the collection of at least one tire, in particular with reference to the first aspect of the invention, or obtained according to the process described with reference to the second aspect of the invention; - the crushing of said at least one tire to obtain crushed particles; - a transformation step of said crushed particles into granules that can be transformed by a hot transformation process, for example by extrusion-molding, said transformation step including an extrusion-granulation step.

[0200] The definitions, variant embodiments, embodiments with reference to the first aspect of the invention can be combined with the second, third, or fourth aspect of the invention.

[0201] The present invention relates, according to a fourth aspect, to a multilayer assembly for the manufacture of a tire by thermocompression, in particular for its implementation in the process of manufacturing a tire according to any one of the embodiment variants with reference to the second aspect of the invention.

[0202] Advantageously, the multilayer assembly is in the form of a strip comprising two free ends or ends joined together to form a torus.

[0203] Advantageously, said multilayer assembly comprises at least one heat-fusible textile part, and at least one non-heat-fusible textile part.

[0204] Advantageously, said multilayer assembly comprises a first textile tube portion including first and second textile layers, and a second textile tube portion including third and fourth textile layers, and at least one of the first textile tube portion and of the second textile tube portion includes at least one heat-fusible textile part, and at least one of the first textile tube portion and of the second textile tube portion includes at least one non-heat-fusible textile part.

[0205] In one variant, the major component by mass relative to the total mass of said multilayer assembly is a thermoplastic polyurethane. Brief description of the drawings

[0206] The invention will be better understood upon reading the following description of embodiments of the invention given by way of non-limiting examples, with reference to the accompanying drawings, in which:

[0207] [Fig-1] [Fig.1] schematically represents a first example of a tire according to the invention;

[0208] [Fig.2] [Fig.2] schematically represents, from a side view, a first example of a multilayer assembly according to the invention for the manufacture of a tire;

[0209] [Fig.3] [Fig.3] schematically represents, from the side, a second example of a multilayer assembly according to the invention for the manufacture of a tire;

[0210] [Fig.4] [Fig.4] schematically represents, from the side, a third example of a multilayer assembly according to the invention for the manufacture of a tire;

[0211] [Fig.5] [Fig.5] schematically represents, from the side, a fourth example of a multilayer assembly according to the invention for the manufacture of a tire;

[0212] [Fig.6] [Fig.6] schematically represents, from the side, a fifth example of a multilayer assembly according to the invention for the manufacture of a tire;

[0213] [Fig.7] [Fig.7] schematically represents, from the side, a sixth example of a multilayer assembly according to the invention for the manufacture of a tire;

[0214] [Fig.8] [Fig.8] schematically represents, in plan view, the arrangement of a textile layer of a textile tube or a portion of a textile tube according to the invention, for example as shown in figures 2 to 7;

[0215] [Fig.9] [Fig.9] schematically represents, in a flat plane, the first and second textile layers of a second example of a textile tube according to the invention;

[0216] [Fig. 10] [Fig. 10] schematically represents, in flat, the first textile layer of a fifth example of a textile tube according to the invention;

[0217] [Fig. 11] [Fig. 11] schematically represents, in flat, a sixth example of a knitted tube according to the invention forming all or part of a multilayer assembly according to the invention for the manufacture of a tire;

[0218] [Fig. 12] [Fig. 12] schematically represents, flat and viewed from an external face, the sixth example of a tube according to [Fig. 12] folded in three;

[0219] [Fig. 13] [Fig. 13] schematically represents, flat and viewed from an inner face, the sixth example of a tube according to [Fig. 12] folded in three;

[0220] [Fig. 14] [Fig. 14] schematically represents, in perspective, the sixth example of a tube according to [Fig. 12] folded in three and whose ends are joined together to form a torus. Description of the implementation methods

[0221] Fig. 1 schematically represents a first example of a tire 10 according to the invention comprising a tread 15, a first sidewall 20 and a second sidewall 25. Advantageously, the first and second sidewalls 20, 25 comprise first and second free longitudinal edges 21, 26 reinforced and forming first and second bead elements 22, 27. The first and second sidewalls 20, 25 advantageously extend on either side of the tread 15. Advantageously, the tire 10 has a general shape of a longitudinally open torus and extends circumferentially (not shown) according to the intended diameter of the tire 10. Advantageously, the tread 15, the first and second sidewalls 20, 25, and the bead elements 22, 27 are of unit molded construction and are formed from a main composite material 30. The main composite material 30 has an axis longitudinal Lmc, extending circumferentially over the length of the tire 10, and a transverse axis Tmc, substantially perpendicular to the axis Lmc.

[0222] Fig. 2 schematically represents a first example of a multilayer assembly 40 according to the invention for the manufacture of a tire comprising a textile tube 50 folded in two and thus forming a first textile portion of tube 42 and a second textile portion of tube 44 connected by the fold 45. The first textile portion of tube 42 comprises a first textile layer 42a and a second textile layer 42b, the second textile portion of tube 44 comprises a third textile layer 44a and a fourth textile layer 44b. The first and / or second and / or third and / or fourth textile layer(s) may each comprise one or more fully or partially heat-fusible multifilamentary and / or monofilamentary yarn(s) and one or more non-heat-fusible monofilamentary and / or multifilamentary yarn(s), in particular whose linear density (dtex) and mass fraction vary according to the textile layer to be functionalized.Preferably, tube 50 is a knitted tube produced on a small-diameter circular knitting machine. Advantageously, the stitch pattern of the first knitted layer 42a can be the same as or different from the stitch pattern of the second knitted layer 42b, or even of the third or fourth knitted layer 44a or 44b.

[0223] Advantageously, the first portion of tube 42 and the second portion of tube 44 differ in at least one physical property and / or one chemical property, in particular chosen from: the composition of a yarn, the fineness of a yarn, the mass fraction of heat-fusible textile material, the mass fraction of non-heat-fusible textile material.

[0224] The multilayer assembly 40 may also include one or more heat-fusible polymer sheets 46, which may be arranged on the outer face of the first layer 42a and / or inside the first tube segment 42 and / or between the first tube segment 42 and the second tube segment 44 and / or inside the second tube segment 44 and / or on the outer face of the fourth layer 44b. The heat-fusible sheet(s) 46 may be made of at least one polyolefin or a polyolefin elastomer or of polyurethane, for example, a polyurethane elastomer. Advantageously, said multilayer assembly 40 is generally shaped into a torus, in particular by joining the free ends 48 and 49 of the tube 50, which is folded in half and then heat-compressed.The said multilayer assembly 40 advantageously comprises a heat-fusible textile part, and a non-heat-fusible textile part, and optionally a non-heat-fusible textile part formed from the heat-fusible sheet(s) 46.

[0225] Advantageously, the torus-shaped multilayer assembly 40 is arranged in a mold assembly comprising a determined molding volume, and then closed. In a hermetic manner, pressure or a vacuum is applied to the multilayer assembly to push / press it against the internal walls of the mold, simultaneously with the application of a heating temperature to melt and / or soften the targeted hot-melt material of the multilayer assembly 40. Advantageously, the pressure can be applied using a deformable, inflatable bladder located inside the torus formed from the multilayer assembly 40, which is inflated during thermocompression. Thermocompression can also be carried out using a rigid, non-inflatable insert, such as a counter-mold placed within the internal volume of the molding assembly. Advantageously, the thermocompression process yields a tire comprising a tread, first and second sidewalls, and optionally bead elements.

[0226] Advantageously, the arrangement of a sheet 46 in a thermoplastic elastomer in the multilayer assembly 40 so as to form at least in part the external face of the tread makes it possible to improve the abrasion resistance and adhesion of the tread.

[0227] The textile tube 50 has a longitudinal axis L, corresponding in this example to the direction of the columns of stitches or warp direction or to the direction of knitting or weaving, and a transverse axis T, substantially perpendicular to the axis L. The transverse axis T corresponds preferably to the weft direction or to the direction of the rows of stitches.

[0228] Advantageously, the textile tube 50 has a unitary textile construction, in particular a unitary knitted construction. The textile tube 50 is thus advantageously obtained directly from a knitting machine without the additional step of attaching another textile piece to the tube 50, except for the possible finishing of the tube 50's edges by stitching. The tube portions 42 and 44 thus share at least one yarn, in particular a knitted yarn.

[0229] Advantageously, the multilayer assembly 40 has a general band shape comprising first and second free ends 48,49, and a longitudinal axis corresponding to the L axis and a transverse axis corresponding to the T axis.

[0230] In the prior art, tire manufacturing comprises numerous steps: manufacturing the tread by impregnating a textile backing with rubber, then manufacturing the casing by coating a textile backing with resin, and finally assembling the tread with the casing during the molding of the casing and tread together. The molding also allows for the vulcanization of the polymer impregnating the tread. Finally, bead elements, particularly metallic ones, are assembled along the free longitudinal edges. In the present invention, a main composite material forming the tread, the first and second sidewalls, and is advantageously obtained in a single thermocompression step from dry (and therefore solvent-free) material(s). possibly the curtain rod components, and this from thermoplastic material(s) that can be easily recycled together without separation.

[0231] Figure 3 schematically represents, in side view, a second example of a multilayer assembly 60 according to the invention for manufacturing a tire, which can correspond to the multilayer assembly 40 of Figure 1, except that the tube portion 42 is inserted into the internal volume of the tube portion 44. In this case, the tube portions 42 and 44 are coaxial in Figure 3. The tube portions are also shown in Figure 3 as having a unitary textile construction, in particular knitted.

[0232] Figure 4 schematically represents a side view of a third example of a multilayer assembly 70 according to the invention for manufacturing a tire, which can be compared to the multilayer assembly 60 of Figure 2, except that the tube portions 42 and 44 are two separate tubes 42' and 44', and are therefore not of unitary textile construction. The tubes 42' and 44' are shown superimposed in Figure 4 but could be arranged coaxially, as shown in Figure 3.

[0233] Figure 5 schematically represents a side view of a fourth example of a multilayer assembly 80 according to the invention for manufacturing a tire comprising three superimposed, separate tubes 90, 94, and 96. The tubes 90, 94, and 96 are not of unit textile construction. The tubes 90, 94, and 96 are preferably knitted, particularly on a circular knitting machine. Advantageously, the first tube 90 comprises a first textile layer 90a and a second textile layer 90b, the second tube 94 comprises a third textile layer 94a and a fourth textile layer 94b, and the third tube comprises a fifth textile layer 96a and a sixth textile layer 96b.

[0234] Advantageously, the first textile layer 90a and / or the second textile layer 90b and / or the third textile layer 94a and / or the fourth textile layer 94b and / or the fifth textile layer 96a and / or the sixth textile layer 96b may each comprise one or more monofilamentary and / or multifilamentary yarns, at least partially heat-fusible, and one or more non-heat-fusible monofilamentary and / or multifilamentary yarns. One or more heat-fusible polymer sheets 98 may be sandwiched between and / or inside the tubes 90, 94, and 96 and / or on the outer face of the first layer 90a and / or on the outer face of the sixth layer 96b.

[0235] Fig. 6 schematically represents a side view of a fifth example of a multilayer assembly 100 according to the invention for the manufacture of a tire which may be similar to the multilayer assembly 80 except that the tubes 90, 94 and 96 are portions of tube 90', 94' and 96' of unitary textile construction, in particular knitted, and are in a single tube 110. The tube 110 thus advantageously comprises two folds 112 and 114.

[0236] Figure 7 schematically represents a side view of a sixth example of a multilayer assembly 120 according to the invention for manufacturing a tire, which may be similar to the multilayer assembly 100 except that tubes 90, 94, and 96 are coaxial. Tube 96 is inserted into tube 94, and tubes 94 and 96 are inserted into tube 90.

[0237] Figure 8 schematically represents, in plan view, an example of a first textile layer 130 of a textile tube or a portion of a tube 132 according to the invention. The second textile layer of the tube or portion of a tube 132 may be similar to the first textile layer 130.

[0238] The first textile layer 130 advantageously comprises a central zone 134 for the tread, and first and second lateral zones 136,138 respectively for a first sidewall and a second sidewall.

[0239] Advantageously, the first textile layer 130 and the tube portion or tube 132 comprise a longitudinal axis L1 and a transverse axis T1 substantially perpendicular to the axis LL. Advantageously, the central area of ​​the tread 134 comprises V-shaped or chevron patterns (or an inverted V, not shown) of knitted mesh or woven floats 140, the branches of which are inclined with respect to the longitudinal axis L1; in particular, the first lateral branches extend along a longitudinal direction L2 forming an angle 11 with the transverse axis T1 of between 15° and 50°. Advantageously, the V-shaped patterns comprise first V-shaped patterns and second V-shaped patterns knitted or woven with yarn(s) different from the yarn(s) of the first V-shaped patterns. The first V-shaped patterns alternate with the second V-shaped patterns along the length of the central area of ​​the tread 134.For example, the first V-patterns are knitted or woven with a composite yarn comprising two multifilament polyamide yarns, in particular PA 6, and a heat-fusible monofilament polyurethane yarn, and the second V-patterns are knitted or woven with a composite yarn comprising two heat-fusible monofilament polyurethane yarns and a multifilament polyamide yarn, in particular PA 6. Advantageously, a first V-pattern comprises a higher mass fraction of heat-fusible textile than the mass fraction of heat-fusible textile in a second V-pattern. The arrangement of the first and second patterns along the central zone 134 improves the mechanical properties (tensile strength, etc.) of the textile reinforcement in the tire.

[0240] Advantageously, the V-shaped, or chevron, (or inverted V-shaped not shown) patterns of knitted stitches or woven floats 140 can extend into the first lateral zone 136, and possibly into the second lateral zone 138.

[0241] Figure 9 schematically represents, in plan view, the first and second textile layers 140, 142 of a portion of a textile tube 147 or of a textile tube 147 having a longitudinal axis L3. Advantageously, the first textile layer 140 comprises lines of knitted mesh or woven floats extending in a first direction L4 and inclined with respect to the axis L3 in the central area 144 and the second textile layer 142 comprises lines of knitted mesh or woven floats 145 extending in a second direction L5 and inclined with respect to the axis L3 in the central area 146, the direction L5 being opposite to the direction L4. Advantageously, the 145 mesh lines include first and second 145 mesh lines, the first 145 mesh lines include more non-heat-fusible textile portion than the second 145 mesh lines.This arrangement allows the textile reinforcement lines to be oriented within the final composite material, and therefore within the tire, in order to improve its mechanical properties.

[0242] The arrangement of the first and second textile layers 140 and 142 can be repeated for the third and fourth textile layers for a second tube segment or a second tube, and optionally for the fifth and sixth layers for a third tube segment or a third tube. The first, second, or third tube segments can be arranged as described herein, for example, overlapping or coaxial. The inclination of the knitted mesh lines or woven floats can vary from one textile layer to another depending on the mechanical properties required for the final textile reinforcement in the main composite material.

[0243] Advantageously, the knitted mesh lines or woven floats 141, respectively 145, can extend into the first lateral zone 144b, respectively 146b, and possibly into the second lateral zone 144c, respectively 146c.

[0244] Figure 10 schematically represents, in a flat plane, the first textile layer 150 of an example of a textile tube 160 or a portion of a tube 160 according to the invention. The first textile layer 150 comprises a central textile zone 154 intended to form all or part of a tread of a tire according to the invention and lateral zones 152, 153 intended to form all or part of the first and second sidewalls, respectively, of a tire according to the invention. Advantageously, the central zone 154 comprises a central sub-zone 154a disposed between the first and second lateral sub-zones 154b and 154c. Advantageously, the central subzone 154a has a mass fraction of hot-melt material Fl, and the lateral subzones 154b and 154c have mass fractions of hot-melt material F2 and F3 respectively, preferably Fl is greater than F2 or F3, even more preferably Fl is greater than at least twice F2 or F3.This arrangement allows for the formation of a longitudinal band comprising more thermally fused material in the central sub-zone 154a. compared to lateral subzones 154b and 154c. In particular, the central subzone 154a comprises knitted or woven float loops projecting from the outer face of the textile layer to provide more fusible textile material; for example, these are terry loops. The lateral textile zones 152 and 153 have a mass ratio of fusible textile to non-fusible textile ranging from 20:70 to 45:45.

[0245] Advantageously, the tube portion or tube 160 can be associated with the tube portion or tube 132 or 147, possibly according to the arrangements described in figures 2 to 7 depending on whether the tubes are separate or the tube portions are of unitary textile construction.

[0246] In one variant, the central zone 154 can be formed from the central subzone 154a, the first lateral zone 152 can be formed from the subzone 154b, and the second lateral zone 153 can be formed from the subzone 154c.

[0247] Figure 11 schematically represents, in plan view, a sixth example of a knitted tube 170 according to the invention intended to form a multilayer assembly according to the invention, in whole or in part, for the manufacture of a tire. The knitted tube 170 comprises first, second, and third knitted tube portions 180, 190, and 200, which are therefore of knitted unit construction. Each knitted tube portion 180, 190, 200 comprises two superimposed textile layers.

[0248] The knitted tube portion 180 comprises first and second 184 superimposed textile layers, the knitted tube portion 190 comprises third and fourth 194 superimposed textile layers, and the knitted tube portion 200 comprises fifth and sixth 204 superimposed textile layers.

[0249] In Figures 12, 13, and 14, the tube portions 180, 190, and 200 are superimposed on one another; they could alternatively be arranged so as to be coaxial. The tube 170, thus folded in three, advantageously forms a multilayer assembly 210 in which the free ends 170a and 170b of the folded tube 170 are joined together to form a main torus 220. The multilayer assembly 210 thus comprises six superimposed textile layers.

[0250] In particular, the first, second, third and fourth textile layers of the tube portions 180,190 comprise, across their entire width, lines of knitted mesh inclined with respect to the longitudinal axis L7 and extending along a longitudinal direction L8. The composition of said layers is preferably similar to that of the central textile zones 144 and 146 shown in [Fig.9].

[0251] The composition of the fifth and sixth 204 textile layers of the portion of tube 200 is preferably similar to that of the variant of the textile layer 150 described above with reference to [Fig. 10].

[0252] The multilayer assembly 210, in the form of a main tube 220, advantageously comprises the fifth textile layer 204 on its outer face such that the central zone 204a forms at least partially the tread of the tire after thermocompression, and the lateral zones 204b and 204c partially form the first and second sidewalls of the tire. Advantageously, the central zone 204 may be similar to the central sub-zone 154a, the lateral zone 204b may be similar to the sub-zone 154b, and the lateral zone 204c may be similar to the sub-zone 154c.

[0253] Advantageously, the multilayer assembly 210 is arranged in a mold assembly comprising a molding insert, inflatable or not, disposed inside the main tube 220. Then, pressure or vacuum is applied to the molding volume comprising the multilayer assembly 210. The multilayer assembly 210 is heated so as to melt or soften its thermofusible textile part to form a thermoplastic polymer matrix impregnating the non-thermofusible textile part, said non-thermofusible textile part forming the textile reinforcement assembly.

Claims

Demands

1. Tire (10) comprising a tread (15) characterized in that said tread comprises a main composite material (30) which is of unit molded construction and which comprises a thermoplastic polymer matrix and a textile reinforcement assembly, and in that said textile reinforcement assembly comprises at least one textile reinforcement element which is a knitted tubular element.

2. Tire according to claim 2, characterized in that the main composite material (30) forms at least 80% by mass of the tread (15).

3. Tire according to claim 1 or 2, characterized in that said textile reinforcement assembly comprises at least two textile layers (42a,90a,42b,90b,44a,44b,94a,94b,96a,96b,130,140,150).

4. Tire according to claim 3, characterized in that said textile reinforcement assembly comprises at least: a first textile layer (42a,90a,130,140,150), a second textile layer (42b,90b, 142), a third textile layer (44a,94a) and a fourth textile layer (44b,94b).

5. Tire according to claim 4, characterized in that said textile reinforcement assembly comprises a first portion of textile tube (42,42',90,90'), the first portion of textile tube comprising said first (42a,90a) and second (42b,90b) textile layers, and in that said textile reinforcement assembly further comprises a second portion of textile tube (44,44',94,94'), the second portion of tube comprising said third (44a,94a) and fourth (44b,94b) textile layers.

6. Tire according to claim 5, characterized in that said first (42,42',90,90') and second (44,44',94,94') tube portions are arranged one above the other or arranged one inside the other.

7. Tire according to any one of claims 4 to 6, characterized in that the first (42a,90a) and second (42b,90b) textile layers are in a first textile element of unitary textile construction reinforcement, and in that the third (44a,94a) and fourth (44b,94b) textile layers are in a second textile element of unitary textile construction reinforcement.

8. Tire according to any one of claims 4 to 6, characterized in that the first (42a), second (42b), third (44a) and fourth (44b) textile layers are in a first textile element of unitary textile construction reinforcement.

9. Tire according to any one of claims 3 to 8, characterized in that the main composite material (30) comprises at least one intermediate thermoplastic polymer layer (46, 98), said intermediate thermoplastic polymer layer being disposed between two adjacent textile layers.

10. Tire according to any one of claims 1 to 9, characterized in that the main composite material (30) comprises at least one external thermoplastic polymer layer (46, 98), said external thermoplastic polymer layer being disposed in an external part of the tread (15) intended to come into contact with the ground.

11. Tire according to any one of claims 1 to 10, characterized in that the mass fraction of thermoplastic material(s) in the main composite material (30) is greater than or equal to 80%.

12. Tire according to any one of claims 1 to 11, characterized in that the thermoplastic polymer matrix comprises polyurethane, in particular comprises predominantly by mass polyurethane.

13. Tire according to any one of claims 1 to 12, characterized in that the main composite material (30), preferably the thermoplastic polymer matrix, comprises a first part including a first aesthetic property selected from a first color and a first design, and a second part including a second aesthetic property selected from a second color and a second design, the first aesthetic property being different from the second aesthetic property.

14. A tire according to any one of claims 1 to 13, characterized in that the main composite material (30), preferably the thermoplastic polymer matrix, comprises a transparent or translucent portion forming a viewing window through which at least a portion of the textile reinforcement assembly is visible from outside the tire.

15. Tire according to any one of claims 1 to 14, characterized in that said textile reinforcement assembly comprises one or more yarn(s) comprising at least one material selected from: polyesters; in particular high tenacity polyesters; polyamides; aramids; polyolefins; celluloses; glasses, or a mixture thereof.

16. Tire according to any one of claims 1 to 15, characterized in that said tire further comprises at least one sidewall (20,25) and in that said principal composite material (30) forms at least in part said at least one sidewall.

17. Tyre according to claim 16, wherein the mass fraction of the textile reinforcement assembly in the tread (15) is greater, in particular by at least two or three times, than the mass fraction of the textile reinforcement assembly in said at least one sidewall (20,25).

18. Tyre according to either of claims 16 and 17, characterized in that the tread (15) comprises at least one ERBR textile reinforcement element, and in that said at least one sidewall (20,25) comprises at least one ERPF textile reinforcement element different from said ERBR textile reinforcement element of the tread.

19. Tyre according to any one of claims 16 to 18, characterized in that the surface mass (g / m2) of said at least one sidewall (20,25) is less than the surface mass (g / m2) of the tread (15).

20. Tire according to any one of claims 1 to 19, characterized in that said tire (10) comprises two free longitudinal left and right edges (21,26), in that at least one of said two free longitudinal left and right edges comprises a bead element (22,27), and in that said principal composite material (30) forms at least part of said bead element.

21. Tyre according to any one of claims 1 to 20, characterized in that the tyre (10) comprises at most 10% by mass of vulcanized rubber(s) and / or of one or more thermosetting polymer(s), optionally vulcanized.

22. A method for manufacturing a tire, in particular according to any one of claims 1 to 21, characterized in that it comprises the steps of: a) preparing a multilayer assembly (40,60,70,80,100,120,210) comprising at least one heat-fusible textile part and at least one non-heat-fusible textile part; b) thermo-compressing said multilayer assembly with a mold configured to mold a tread (15) of a tire (10), by heating said multilayer assembly so as to melt said thermofusible textile part; c) obtaining a unit molded construction main composite material (30) comprising a thermoplastic polymer matrix and a textile reinforcement assembly, said composite material forming at least in part the tread of a tire.

23. A manufacturing process according to claim 22, characterized in that step a) comprises the preparation of a multilayer assembly (40,60,70,80,100,120,210) comprising a first textile layer (42a,90a,130,140,150) comprising at least one yarn A which is at least partly heat-fusible, a second textile layer (42b,90b,142,184) comprising at least one yarn B which is at least partly heat-fusible, a third textile layer (44a,94a) comprising at least one yarn C which is at least partly heat-fusible and a fourth textile layer (44b,94b,194) comprising at least one yarn D which is at least partly heat-fusible; and in that step b) includes thermocompression of the multilayer assembly with a mold configured to mold a tread (15) of a tire (10), by heating said multilayer assembly so as to melt at least in part said yarns A, B, C and D, of said first, second, and third and fourth textile layers.

24. A manufacturing method according to either of claims 22 and 23, characterized in that the non-heat-fusible textile part comprises a first polyurethane having a melting or softening temperature T1, and the heat-fusible textile part comprises a second polyurethane having a melting or softening temperature T2, T1 being greater than T2.

25. A manufacturing method according to any one of claims 22 to 24, characterized in that the multilayer assembly (40,60,70,80,100,120,210) comprises at least one textile reinforcement element comprising knitted loops or woven floats, said knitted loops or said woven floats comprising one or more yarns at least partly heat-fusible.

26. A manufacturing method according to any one of claims 22 to 25, characterized in that in step c) the multilayer assembly (40,60,70,80,100,120,210) is heated to a temperature greater than or equal to 100°C and less than or equal to 250°C.

27. ​​A tire recycling process, characterized in that it comprises: - the collection of at least one tire (10) according to any one of claims 1 to 21, or obtained according to any one of claims 22 to 26; - the shredding of said at least one tire to obtain shredded particles; - a step of transforming said shredded particles into granules that can be transformed by a process of transforming a heated plastic material, for example by extrusion-molding, said step of transforming a heated plastic material comprising an extrusion-granulation step.

28. Multilayer assembly (40, 60, 70, 80, 100, 120, 210) for manufacturing a tire (10) by thermocompression, in particular for its implementation in the manufacturing process according to any one of claims 22 to 26, characterized in that it is in the form of a strip comprising two free ends (48, 49, 170a, 170b) or joined together to form a torus (220), and in that said multilayer assembly (40, 60, 70, 80, 100, 120, 210) comprises a first portion of textile tube (42, 42', 90', 94', 96', 132, 147, 180) comprising first (42a, 90a, 130, 140, 150) and second textile layers (42b, 90b, 142, 184), and a second portion of textile tube (44, 44', 190) comprising third and fourth textile layers (44b, 94b, 194), and in that at least one of the first portion of textile tube and the second portion of textile tube comprises at least one heat-fusible textile part,and in that at least one of the first portion of the textile tube and the second portion of the textile tube comprise at least one non-heat-fusible textile part.

29. Multilayer assembly according to claim 28, characterized in that the major component by mass relative to the total mass of said multilayer assembly (210) is a thermoplastic polyurethane.

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