Method for producing at least one part of an article of footwear, for example a shoe, a sandal, a boot, etc, and in particular an article of footwear for engaging in sport

Abstract

A method (100) for producing at least one part of an article of footwear (10) comprising the following steps: - providing (103) a mould (1) defining an open cavity (2), a shape of at least part of the cavity (2) corresponding to a shape of a sole (3) of the article of footwear (10), the cavity (2) being configured to receive, via at least one injection channel (4, 4', 4'', 4''') opening into the cavity (2), a mixture comprising a melt and a supercritical fluid; - placing (105) a rim (5) of an opening of the open cavity (2) in contact with a meeting zone (6) at which a surface (7) of at least one part of an upper (9) of the article of footwear (10) meets the sole, such that the surface (7) of the at least one part of the upper (9) closes the cavity at the region of contact between the meeting zone (6) and the rim (5); - pressurizing (105bis) the cavity (2); - injecting (107) the mixture into the cavity (2); - depressurizing (108) the cavity (2) of the mould, to trigger an expansion of the mixture in the cavity (2) and form the sole (3) from a foamed material resulting from the expansion of the mixture, the at least one part of the surface (7) of the at least one part (9) of the upper being caught in said foamed material of the sole (3).

Description

[0001] DESCRIPTION

[0002] TITLE: Method of manufacturing at least part of an item of footwear, for example a shoe, a sandal, a boot, etc., and in particular an item of footwear for practicing a sport.

[0003] The present invention relates to the field of the manufacture of footwear, for example shoes, and in particular to the manufacture of footwear comprising a light and shock-absorbing sole, and in particular footwear for practicing a sport.

[0004] It is known to first manufacture a sole and then to connect the sole to an upper, in particular at least partly made of textile, in a second stage. The manufacture of footwear articles with a lightweight and shock-absorbing sole requires many steps because the sole is made separately, most often from cross-linked ethylene vinyl acetate (EVA), then assembled by gluing to the upper.

[0005] The disadvantage of this known process is that it requires numerous manual gluing operations, which consume a lot of energy.

[0006] On the other hand, two direct injection processes on the rod are already known:

[0007] - injection of thermoplastic, PVC or other elastomers. With this process, the material can be foamed using a chemical or physical foaming agent; however, the disadvantage of this process is that the resulting shoe sole material does not have the expected properties of a lightweight and cushioning sole. The lowest sole density that can be achieved with this process is greater than 0.5 g / cm3. In addition, the cushioning and comfort properties sought for the soles of running shoes, for example, are not achievable with this manufacturing process.

[0008] - direct injection of polyurethane onto the upper. In this case, the foaming is obtained by chemical reaction of 2 compounds (Polyol and Isocyanate). The disadvantage of this process is that the density of the sole remains high (>0.35 g / cm3 in the best case).

[0009] Furthermore, the non-thermoplastic nature of polyurethane makes recyclability extremely difficult.

[0010] The invention therefore aims to propose a solution to all or part of these problems. To this end, the present invention relates to a method of manufacturing at least part of an item of footwear, for example a shoe, and in particular an item of footwear for practicing a sport, comprising the following steps:

[0011] - providing a mold defining an open cavity, a shape of at least a portion of the cavity corresponding to a shape of a sole of the footwear article, the cavity being configured to receive, via at least one injection channel opening into the cavity, a mixture comprising a molten material and a supercritical fluid;

[0012] - placing a rim of an opening of the open cavity in contact with a docking zone of a surface of at least one part of an upper of the footwear article, so that the surface of the at least one part of the upper ensures a closure of the cavity at the level of contact between the docking zone and the rim;

[0013] - pressurize the cavity;

[0014] - inject the mixture into the cavity;

[0015] - depressurizing the mold cavity, to trigger an expansion of the mixture in the cavity and form the sole in a foamed material resulting from the expansion of the mixture, at least a portion of the surface of the at least a portion of the upper being taken in said foamed material of the sole.

[0016] According to these provisions, the method makes it possible to obtain, in a single injection step, a light and shock-absorbing sole of the footwear article connected to a part of an upper of the footwear article, with good resistance to detachment of the sole and the upper.

[0017] According to one embodiment, the dimensions of the shape of at least one part of the cavity are the dimensions on a scale of between 1:0.98 and 1:1.02, advantageously 1 to 1, of the shape of the sole of the footwear article.

[0018] According to one embodiment, the pressurization of the cavity is accompanied by the simultaneous creation of a counter-pressure, advantageously of a substantially identical value, in an area of ​​at least one part of the rod on the other side of the closure relative to the cavity.

[0019] According to these provisions, the counter-pressure, advantageously of a substantially identical value, makes it possible to avoid leaks, at the level of contact between the docking zone and the rim, of a gas pressurizing the cavity.

[0020] Advantageously, the area of ​​the at least part of the upper on the other side of the closure relative to the cavity can be depressurized simultaneously with the depressurization of the mold cavity to trigger an expansion of the mixture in the cavity and form the sole during the method according to the invention.

[0021] According to these provisions, a pressurization pressure in the cavity followed by a depressurization in the cavity allows an expansion of the mixture and the obtaining of the light and cushioning foamed material of the sole.

[0022] According to these provisions, the density of the sole is between 0.1 g / cm3 and 0.4 g / cm3, preferably between 0.15 g / cm3 and 0.25 g / cm3.

[0023] According to one embodiment, the invention comprises one or more of the following characteristics, alone or in a technically acceptable combination.

[0024] According to one method of implementation, a pressurization pressure of the cavity is between 3 bars and 50 bars, preferably between 10 bars and 30 bars, preferably equal to 15 bars.

[0025] According to one embodiment, the method further comprises, prior to the step of pressurizing the cavity, the following step:

[0026] - placing a cover on the mold so as to form with the mold a closed volume comprising the cavity, and a complementary part of the cavity in said closed volume, the at least one part of the rod being located inside said closed volume, the complementary part and the cavity being located on either side of the closure of the cavity at the level of contact between the docking zone and the rim.

[0027] A pressurization pressure in the complementary part of the closed volume, advantageously identical to the pressurization pressure of the cavity, makes it possible to create the counter-pressure in order to avoid leaks, at the level of contact between the docking zone and the rim, of a pressurization gas of the cavity.

[0028] According to one embodiment, the cover is configured to form with the mold a sealed closed volume, in particular gas-tight, around at least one part of the rod, so as to allow the creation of said counter-pressure inside this sealed closed volume, in particular by receiving the pressurizing gas of the cavity in this sealed volume, in order to avoid leaks, at the contact between the docking zone and the rim, of a pressurizing gas of the cavity.

[0029] According to one embodiment, the method comprises a step of assembling the part of the upper connected to the sole, with another part of the upper, the assembly forming the footwear item.

[0030] According to one embodiment, the assembly step comprises sewing the other part of the upper with the part of the upper connected to the sole.

[0031] According to one embodiment, the method further comprises the following steps, implemented before the step of placing the rim of the opening of the open cavity in contact with the docking zone of a surface of at least one part of a rod:

[0032] - provide a support having a shape corresponding to the shape of a foot,

[0033] - covering, at least in part, an external surface of the support with the at least one part of the upper of the footwear article, the at least one part of the surface of the at least one part of the upper covering a part of the external surface of the support corresponding to a sole of said foot, so that after placing the cover on the mold, the closed volume further comprises the support with the at least one part of the upper.

[0034] According to one embodiment, the at least part of the rod is a complete rod.

[0035] Depending on the method of implementation, the support is made of aluminum, steel, or plastic.

[0036] According to these provisions, the process makes it possible to obtain, in a single injection step and with a single mold, a complete footwear article comprising the sole of the footwear article connected to the complete upper of the shoe.

[0037] According to one embodiment, the mold is in a single part. According to one embodiment, the mold comprises at least two parts and the provision step comprises a step of assembling the at least two parts to form the mold.

[0038] According to one embodiment, the mold comprises a ring portion comprising a first ring half and a second ring half, the first half being movable relative to the second ring half in a sliding direction, such that a sliding movement of the first half towards the second half in the sliding direction closes the ring portion of the mold, while a sliding movement of the first half and the second half in an opposite direction opens the ring portion of the mold by separating the two halves of the ring portion.

[0039] According to one embodiment, the mold further comprises a mold bottom comprising a hood and a bell, said bell being configured to envelop the hood, and the first ring half and the second ring half of the mold when the ring portion and the mold are closed.

[0040] According to one embodiment, the mold bottom bell comprises a contact interface between the mold bottom bell and the ring portion, said contact interface comprising a first inclined plane configured to slide on a first contact surface of a wall of the first half of the ring, said contact interface comprising a second inclined plane configured to slide on a second contact surface of a wall of the second half of the ring, the first angle of inclination of the first inclined plane and the second angle of inclination of the second inclined plane being configured such that the step of assembling and closing the mold comprises a movement of the mold bottom bell towards the two halves of the ring portion which mechanically produces a sliding movement of the two halves in the direction of bringing the two halves of the ring portion closer together, so as to close the ring portion in contact with the mold bottom.

[0041] According to one embodiment, the mold comprises an elastic device configured to separate the first ring half and the second ring half.

[0042] According to one embodiment, the contact interface between the bell of the mold bottom and the ring portion comprises at least one guide configured to accompany the sliding movement of the two parts of the ring when the bell of the mold bottom moves in the direction transverse to the sliding direction.

[0043] According to these provisions, the mold is actuated alternately in closing, respectively in opening, by a movement of the mold base towards the two halves of the ring part, respectively in the opposite direction.

[0044] According to one embodiment, the cavity is configured to receive the mixture via at least two injection channels opening into the cavity. According to these arrangements, the method makes it possible to obtain even more quickly, and with a more homogeneous filling of the mold cavity, a sole of the footwear article connected to a part of the upper of the footwear article.

[0045] According to one embodiment, the mold comprises at least one injection channel.

[0046] According to one embodiment, the support comprises at least one injection channel.

[0047] According to one embodiment, the method comprises a step of gluing at least one part of the surface of at least one part of the rod, the gluing step being carried out before the injection step.

[0048] According to one embodiment, the at least one portion of the surface of the at least one portion of the rod comprises thermofusible wires configured to melt at an injection temperature of the mixture.

[0049] According to these provisions, the resistance to detachment of the sole and the upper is reinforced.

[0050] According to one embodiment, the method further comprises the following steps:

[0051] - provide inserts configured to be positioned in the mold cavity;

[0052] - position the inserts in the mold cavity.

[0053] According to one method of implementation, the inserts are positioned to be inserted at an external surface of the sole, or to be embedded inside the sole.

[0054] According to these provisions, the abrasion resistance of the sole is reinforced, or the dynamism of the sole is improved, depending on whether the inserts are respectively inserted towards an external portion of the sole, for example with one or more inserts made of rubber or thermoplastic material, or embedded inside the sole, for example with one or more inserts made of carbon plate or thermoplastic material.

[0055] According to one embodiment, a contact surface between an insert and the sole comprises a texture.

[0056] According to one embodiment, the texture comprises a plurality of patterns distributed over a portion of the contact surface according to a density depending on a mechanical stress on the portion of the contact surface.

[0057] According to one embodiment, the density is determined so that on a portion of the contact surface the plurality of patterns occupies a part of the portion of the contact surface, said part being between 1% and 15%, advantageously 6%, of the portion of the contact surface.

[0058] According to one embodiment, the patterns are tubular and / or linear. According to one embodiment, a height of the patterns in a direction transverse to the contact surface is between 1mm and 10mm, preferably equal to 1.6mm.

[0059] According to one method of implementation, a thickness of the patterns, in a direction transverse to the height direction, is between 1mm and 2mm, preferably equal to 1.6mm.

[0060] According to these provisions, the adhesion between the insert and the sole is reinforced, by mechanical adhesion, avoiding the steps of gluing or surface preparation.

[0061] According to one embodiment, an insert positioned to fit at an external surface of the sole comprises at least one through hole, the at least one through hole being matched with a pressurization channel, such that a pressurization gas can pass through the insert.

[0062] According to one embodiment, at least one part of the surface of the at least one part of the rod is at least partly perforated or open.

[0063] According to these provisions, the resistance to detachment of the sole and the upper is reinforced.

[0064] According to one embodiment, at least one part of the surface of at least one part of the rod is textured or perforated in contact with the docking zone.

[0065] According to these provisions, the resistance to detachment of the sole and the upper is further reinforced.

[0066] According to these provisions, a peel resistance greater than 2.5 N / mm is obtained, measured according to the ISO NF EN 1392 standard.

[0067] According to one method of implementation, the molten material is an elastomeric thermoplastic polymer.

[0068] According to one method of implementation, the thermoplastic polymer is a thermoplastic polyurethane (TPU), or an ether-amide block copolymer (PEBA), or an ethylene vinyl acetate (EVA), or a polyolefin, or an ether-ester block copolymer, or a styrene-based elastomer, or a mixture of these different components.

[0069] According to one embodiment, the supercritical fluid is nitrogen in a supercritical state or carbon dioxide in a supercritical state or a mixture of nitrogen and carbon dioxide in a supercritical state.

[0070] According to one embodiment: a majority by mass of the upper being made of a main upper material, and optionally one or more auxiliary upper material(s); a majority by mass of the sole being made of a main sole material, and optionally one or more auxiliary sole material(s), the foamed material, resulting from the expansion of the mixture, comprising said main sole material and said auxiliary sole material(s); the main upper material, and optionally the auxiliary upper material(s), is / are selected from the following materials: polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, a thermoplastic polyurethane (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer,and a polyester, and in that the main sole material, and optionally the auxiliary sole material(s), is / are of the same chemical family as the main upper material, and optionally is / are of the same chemical family as the auxiliary upper material(s), or in that the main sole material, and optionally the auxiliary sole material(s) is / are chemically compatible with the main upper material, and optionally with the auxiliary upper material(s).,

[0071] The main sole material can therefore be from the same chemical family as the main upper material. For example, if the main upper material is a polyolefin, the main sole material is also a polyolefin. If the main upper material is a polyamide, the main sole material is also a polyamide.

[0072] It is understood that two polymers are “chemically compatible” within the meaning of the invention when at the microscopic scale they form a homogeneous medium and no distinct phase is observed.

[0073] This results in a lightweight, shock-absorbing and recyclable shoe, preferably not requiring the application of glue or bonding agent between the upper and the sole.

[0074] In one embodiment, the main sole material, and optionally the auxiliary sole material(s), is / are identical to the main upper material, and optionally is / are identical to the auxiliary upper material(s).

[0075] Since the main upper material, and possibly the auxiliary upper material(s), and the main sole material, and possibly the auxiliary sole material(s), are selected from the same materials, or are chemically compatible with each other, their adhesion is facilitated, as is the manufacture of the footwear and also its recycling. Indeed, it is not necessary to separate all the components of the footwear to recycle it. Recycling can be carried out in a single step by grinding the footwear and then forming granules from said ground materials. The applicant has surprisingly found that the main sole and upper materials listed above have the advantage that they can be presented in very different forms in footwear use and can be recycled several times.

[0076] Advantageously, the main materials, and possibly auxiliary materials, of the upper and sole, are selected so that the granules, at least partly recycled, are capable of being transformed by any plastic shaping technique (in particular hot), for example by injection molding, by injection foaming, by extrusion molding, by extrusion blow molding, by thermoforming or even by thermomolding. The granules resulting from the recycled footwear article according to the invention can be used in the manufacture of a sole or even a shoe component (such as a rear counter, a front hard toe, or even a lateral reinforcement) or even in the manufacture of a yarn (for example by extrusion spinning) for the manufacture of a textile component (for example the manufacture of an upper component or of the entirety of an upper by knitting or weaving) or a foam component.The granules from the footwear item can also be used in the manufacture of a boot.

[0077] Said granules can also be transformed into a nonwoven, for example by a so-called Meltblown or Spunbond technique or by their combination, such as a so-called SMS nonwoven (Spunbond / Meltblown / Spunbond) for example.

[0078] The main upper material may be selected from polyesters, thermoplastic polyurethanes (TPUs), polyolefins, and block copolymers composed of rigid polyamide blocks and flexible polyether blocks.

[0079] The main sole material may be selected from polyesters, thermoplastic polyurethanes (TPUs), polyolefins, and block copolymers composed of rigid polyamide blocks and flexible polyether blocks.

[0080] The upper may comprise a yarn comprising a material selected from: polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethane (TPU), an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester.

[0081] The upper may comprise a textile component, and in that the textile component comprises a yarn comprising the main upper material.

[0082] The upper may comprise a textile part forming a foot receiving area having an external face, and at least one part, in particular a band, comprising an olefinic thermoplastic elastomer, said band being secured to said external face of the textile part and to said sole.

[0083] The sole may comprise a foam component, and / or foam beads, comprising a material selected from: polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, thermoplastic polyurethane (TPU), an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester.

[0084] The upper may include a front hard toe comprising the main upper material or an auxiliary upper material, and / or a rear counter comprising the main upper material or an auxiliary upper material.

[0085] The upper may comprise at least one eyelet for passing at least one lacing element, said at least one eyelet for passing comprises a textile strip comprising at least one thread comprising the main upper material, in particular the main upper material is a polyolefin.

[0086] The rod may comprise a foam component comprising the main rod material, in particular the main rod material is a polyolefin.

[0087] In one embodiment, the upper and / or sole each comprises / comprises, a recycled material from a sole and / or upper of another shoe, and / or a recycled material from a sole and / or upper of a boot.

[0088] Advantageously, the ratio of the mass of the main rod material, and possibly the mass of the auxiliary rod material(s), to the total mass of the rod is greater than or equal to 40%.

[0089] Advantageously, the ratio of the mass of said main rod material and the mass of the auxiliary rod material(s) to the total mass of the rod is greater than or equal to 50%.

[0090] Advantageously, the ratio of the mass of the main sole material, and possibly the mass of the auxiliary sole material(s), to the total mass of the sole is greater than or equal to 40%.

[0091] Advantageously, the ratio of the mass of said main sole material and the mass of the auxiliary sole material(s) to the total mass of the sole is greater than or equal to 50%.

[0092] The footwear article may comprise at most 10% by mass of one or more contaminating material(s) not chosen from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethane (TPU), an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester, in particular at most 10% by mass of one or more thermoplastic contaminating material(s) and / or at most 5% by mass of one or more thermosetting contaminating material(s). Advantageously, the main sole material, and possibly the auxiliary sole material(s), is / are derived at least in part from the recycling of at least one other item of footwear.

[0093] The method may further include collecting the footwear article, and may include processing the footwear article into thermoplastic pellets.

[0094] Advantageously, the transformation step includes:

[0095] - a step of grinding said at least one shoe to obtain ground particles;

[0096] - a step of compacting said ground particles to obtain ground and compacted particles, in particular cold or hot,

[0097] - a step of extrusion-granulation of said crushed and compacted particles to obtain granules which can be transformed by a hot transformation process of plastic(s).

[0098] The method may comprise a step of hot transformation of at least a portion of said thermoplastic granules for the manufacture of a plastic part, in particular forming at least in part an article for practicing a sport.

[0099] The invention also relates to a plastic part, in particular forming at least in part an article for practicing a sport, capable of being obtained by this method, in particular said part is a fin blade.

[0100] According to one aspect, the invention also relates to an item of footwear, for example a shoe, and in particular an item of footwear for practicing a sport, obtained by the method according to one of the embodiments described above.

[0101] The main upper and sole materials, and possibly the auxiliary upper and / or sole material(s), selected in the present invention may be thermoplastic materials which have the advantage of being derived from olefins. These materials can thus advantageously be transformed several times under heat without their properties degrading significantly, in particular due to oxidation caused by air and / or humidity. This ability allows them to improve the longevity of their recyclability cycle unlike certain polymer materials, such as polyurethanes in particular, which oxidize over time. Advantageously, the footwear article can thus be recycled several times.

[0102] The auxiliary upper material(s) may be different from the main upper material and / or the main sole material.

[0103] The auxiliary rod material(s) may be different from each other.

[0104] The auxiliary sole material(s) may be different from the main sole material and / or the main upper material.

[0105] The auxiliary sole material(s) may be different from each other. By "the main or auxiliary upper material is identical to the main or auxiliary sole material" is understood that the main / auxiliary upper material is in the same basic polymer material as that of the main / auxiliary sole material.

[0106] The same reasoning applies between two auxiliary upper or sole materials which are identical or different.

[0107] “The main or auxiliary upper material is different from the main or auxiliary sole material” means that the main / auxiliary upper material is not in the same basic polymer material as the main / auxiliary sole material.

[0108] Preferably, the main upper material and / or the main sole material is / are chosen from polyolefins, and / or olefinic thermoplastic elastomers, and / or styrenic thermoplastic elastomers, and / or vulcanized thermoplastic elastomers.

[0109] In one embodiment, the main upper material is a thermoplastic polyurethane (TPU), or an ether-amide block copolymer (PEBA), or an ethylene vinyl acetate (EVA), or a polyolefin, or an ether-ester block copolymer, or a styrenic thermoplastic elastomer, or an olefinic thermoplastic elastomer, or a vulcanized thermoplastic elastomer, or a styrene-based elastomer, or a polyester, or a mixture of these different components.

[0110] In one embodiment, the main sole material is a thermoplastic polyurethane (TPU), or an ether-amide block copolymer (PEBA), or an ethylene vinyl acetate (EVA), or a polyolefin, or an ether-ester block copolymer, or a styrenic thermoplastic elastomer, or an olefinic thermoplastic elastomer, or a vulcanized thermoplastic elastomer, or a styrene-based elastomer, or a polyester, or a mixture of these different components.

[0111] Preferably, a vulcanized thermoplastic elastomer is used only in an outsole and not in a midsole. Thus, in one embodiment, only the outsole is the only portion of the sole that may comprise a thermoplastic vulcanizate (TPV).

[0112] Preferably, the auxiliary rod material(s) is / are selected from polyolefins and / or styrenic thermoplastic elastomers and / or olefinic thermoplastic elastomers and / or vulcanized thermoplastic elastomers.

[0113] Preferably, the auxiliary sole material(s) is / are selected from polyolefins and / or styrenic thermoplastic elastomers and / or olefinic thermoplastic elastomers and / or vulcanized thermoplastic elastomers.

[0114] Upper Preferably, the upper comprises a forefoot region configured to cover all or part of the forefoot, and / or a rearfoot region configured to cover all or part of the rearfoot, and / or a medial region configured to cover a medial side of the foot in all or part, and / or a lateral region configured to cover a lateral side of the foot in all or part, and / or an instep region configured to cover all or part of the instep, and / or a leg region configured to cover all or part of the leg.

[0115] Advantageously, the rod comprises (optionally is made of) the main rod material, and optionally one or more auxiliary rod material(s), in particular said auxiliary rod material(s) is / are different from the main rod material and optionally different from each other.

[0116] For example, the main upper material may be a thermoplastic polyurethane (TPU), or an ether-amide block copolymer (PEBA), or an ethylene vinyl acetate (EVA), or a polyolefin, or an ether-ester block copolymer, or a styrenic thermoplastic elastomer, or an olefinic thermoplastic elastomer, or a vulcanized thermoplastic elastomer, or a styrene-based elastomer, or a polyester, or a mixture of these different components, and a first auxiliary upper material may be an olefinic thermoplastic elastomer or a vulcanized thermoplastic elastomer.

[0117] For example, the main rod material may be polypropylene or polyethylene, and the rod comprises a first auxiliary rod material, different from the main rod material, selected from polypropylene and polyethylene. The main rod material may thus be polypropylene and the first auxiliary rod material may be polyethylene.

[0118] In one embodiment, the article of footwear is a shoe, and the main upper material is a thermoplastic polyurethane (TPU), or an ether-amide block copolymer (PEBA), or an ethylene vinyl acetate (EVA), or a polyolefin, or an ether-ester block copolymer, or a styrenic thermoplastic elastomer, or an olefinic thermoplastic elastomer, or a vulcanized thermoplastic elastomer, or a styrene-based elastomer, or a polyester, or a mixture of these different components, and preferably a polyolefin, preferably polypropylene or polyethylene.

[0119] In one embodiment, the main upper material is different from the main sole material, and the sole also comprises a first auxiliary sole material identical to the main upper material (in particular said first auxiliary sole material is not in the majority by mass in the sole). Preferably, the main upper material is a polyolefin, the main sole material is a styrenic thermoplastic elastomer, and the first auxiliary sole material is a polyolefin.

[0120] The main upper material and / or the main sole material and / or the auxiliary upper material(s) and / or the auxiliary sole material(s) may be recycled material(s) from a sole and / or the upper of another shoe or boot and / or plastic(s) and / or be derived from biomass.

[0121] The rod may comprise (in particular may be made of) one or more rod components comprising (in particular made of) said main rod material and / or one or more auxiliary rod materials.

[0122] An upper component may be a textile component, or a reinforcing component, or a lacing component, or a cushioning component, or a cellular component such as foam, or a lace, or an eyelet, or a front toe cap, or a rear or side counter, or a combination of these.

[0123] The textile component may be a fabric, a knit, a nonwoven, a braid, a cable, a spun yarn, a multi-filament yarn, a mono-filament yarn, a set of fibers, or a combination thereof.

[0124] The textile component may be a three-dimensional textile (e.g., a knit or fabric), i.e., comprising upper and lower textile panels connected by intermediate threads extending between said textile panels.

[0125] The textile component may be a knitted component, for example knitted on a flat knitting machine, or on a warp knitting machine, or on a circular warp or weft knitting machine, particularly of small diameter.

[0126] The textile component may be a knitted tube, particularly a knitted sock comprising a knitted heel portion.

[0127] Preferably, the rod comprises one or more rod components assembled by gluing, sewing, or welding (for example by ultrasound or high frequency).

[0128] Preferably, the upper comprises a textile component of unitary textile construction, in particular of unitary knitted or woven construction, said component comprising a forefoot region and / or a rearfoot region and / or a lateral region and / or a medial region and / or an instep region.

[0129] By “unitary textile construction” we mean that the textile component does not include any seam(s) or weld(s) other than those possibly necessary for its shaping, for example to join edges.

[0130] In one embodiment, the upper comprises a foam component, in particular a foam, and / or foam beads, comprising a material selected from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPUs), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester, preferably an olefinic thermoplastic elastomer or a polyolefin, more preferably a polyolefin. Said material may be the main upper material or an auxiliary upper material.

[0131] Preferably, the rod comprises a foam component, particularly a foam, and / or foam beads, comprising the main rod material.

[0132] In one embodiment, the mass fraction of said main rod material in the rod is greater than or equal to 20%, preferably greater than or equal to 30%, more preferably greater than or equal to 40%.

[0133] Preferably, the mass fraction of said main rod material in the rod is less than or equal to 90%, in particular less than or equal to 80%, more particularly less than or equal to 70%, in particular less than or equal to 60%.

[0134] Alternatively, the mass fraction of said main rod material in the rod may be greater than or equal to 60%, preferably greater than or equal to 70%, more preferably greater than or equal to 80%, preferably greater than or equal to 90%.

[0135] In one embodiment, the surface area fraction occupied by the main rod material in the rod is greater than or equal to 30%, preferably greater than or equal to 40%, more preferably greater than or equal to 50%.

[0136] Preferably, the surface fraction occupied by the main rod material in the rod is less than or equal to 90%, in particular less than or equal to 80%, more particularly less than or equal to 70%.

[0137] Alternatively, the surface area fraction occupied by the main rod material in the rod may be greater than or equal to 60%, preferably greater than or equal to 80%, more preferably greater than or equal to 90%.

[0138] Preferably, the surface fraction occupied by the main rod material and by one or more auxiliary rod material(s) in the rod is greater than or equal to 60%, more preferably greater than or equal to 70%, preferably greater than or equal to 80%.

[0139] In one embodiment, the rod comprises the main rod material and a first auxiliary rod material, the mass fraction of the first auxiliary rod material in the rod is greater than or equal to 5%, preferably greater than or equal to 20%.

[0140] The mass fraction of the first auxiliary rod material in the rod is preferably less than or equal to 60%, preferably less than or equal to 50%, more preferably less than or equal to 40%.

[0141] In one embodiment, the rod comprises the main rod material and one or more auxiliary rod materials, in particular a first and / or a second auxiliary rod material(s); the ratio of the mass of said main rod material, and of the mass of the auxiliary rod material(s), to the total mass of the rod is greater than or equal to 50%, preferably greater than or equal to 60%, more preferably greater than or equal to 70%, preferentially greater than or equal to 80%, in particular greater than or equal to 90%.

[0142] Optionally, the ratio of the mass of said main rod material, and the mass of the auxiliary rod material(s), to the total mass of the rod is less than or equal to 90% or 80%.

[0143] Advantageously, the rod comprises a first rod auxiliary material which is selected from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester; preferably a polyolefin or an olefinic thermoplastic elastomer or a vulcanized thermoplastic elastomer; more preferably a polyolefin.

[0144] Advantageously, the rod comprises a first rod auxiliary material and a second rod auxiliary material which is selected from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPUs), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester; preferably a polyolefin or an olefinic thermoplastic elastomer or a vulcanized thermoplastic elastomer; more preferably a polyolefin.

[0145] Preferably, the first rod auxiliary material is different from the second rod auxiliary material.

[0146] In one embodiment, the article of footwear is a shoe, and the main upper material is selected from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPUs), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester.

[0147] Preferably, the mass fraction of the main rod material in the rod is greater than or equal to 40% and less than or equal to 80%, more preferably less than or equal to 60%.

[0148] Preferably, the mass fraction of the first auxiliary rod material in the rod is greater than or equal to 5%, more preferably less than or equal to 40%, more preferably less than or equal to 30%; for example between 25% and 40%.

[0149] Preferably, the surface fraction of the main rod material which is a polyolefin, in particular polypropylene, in the rod is greater than or equal to 45%. More preferably, the surface fraction of the main rod material and a first auxiliary rod material which is a polyolefin, in particular polyethylene, in the rod is greater than or equal to 70%. In particular, the surface fraction of a second auxiliary rod material, which is an olefinic thermoplastic elastomer or a styrenic thermoplastic elastomer or a vulcanized thermoplastic element, in the rod is greater than or equal to 15%, in particular less than or equal to 30%.

[0150] In one embodiment, the article of footwear is a shoe, and the main upper material is an olefinic thermoplastic elastomer or a vulcanized thermoplastic elastomer, optionally the upper further comprises a first auxiliary upper material, in particular which is a polyolefin, for example polypropylene or polyethylene.

[0151] Preferably, the mass fraction of the main rod material in the rod is greater than or equal to 40% and less than or equal to 80%, more preferably less than or equal to 60%.

[0152] Preferably, the mass fraction of the first auxiliary rod material in the rod is greater than or equal to 5%, more preferably greater than or equal to 20%, in particular greater than or equal to 30% and less than or equal to 50%, more particularly greater than or equal to 35% and less than or equal to 45%.

[0153] Sole

[0154] The sole comprises (in particular is made up of) the main sole material and possibly one or more auxiliary sole materials, in particular different from the main sole material.

[0155] Said auxiliary sole material(s) is / are preferably chosen from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester.

[0156] For example, the main sole material may be a styrenic thermoplastic elastomer and the sole comprises a first auxiliary sole material, which is a polyolefin, for example polypropylene or polyethylene.

[0157] Advantageously, the sole comprises a first auxiliary sole material which is selected from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester; preferably a polyolefin or a styrenic thermoplastic elastomer or a vulcanized thermoplastic elastomer.

[0158] Preferably, the mass fraction of the main sole material in the sole is greater than or equal to 25%, more preferably greater than or equal to 40%, preferably greater than or equal to 50%, more preferably greater than or equal to 60%.

[0159] Preferably, the mass fraction of the main sole material in the sole is less than or equal to 80%.

[0160] Preferably, the mass fraction of the first auxiliary sole material, in the sole, is greater than or equal to 10%, more preferably less than or equal to 40%, preferably less than or equal to 30%, for example between 15% and 25% (upper and lower limits included).

[0161] In one embodiment, the sole comprises the main sole material, and optionally one or more auxiliary sole materials, in particular a first and / or a second auxiliary sole material(s), the ratio of the mass of the main sole material, and optionally of the mass of the auxiliary sole material(s), to the total mass of the sole is greater than or equal to 30%, preferably greater than or equal to 40%, more preferably greater than or equal to 50%, preferably greater than or equal to 60%, more preferably greater than or equal to 70%, preferably greater than or equal to 80%, in particular greater than or equal to 90%.

[0162] Optionally, the ratio of the mass of the main sole material, and possibly the mass of the auxiliary sole material(s), to the total mass of the sole is less than or equal to 90%, in particular less than or equal to 80%, more particularly less than or equal to 70%.

[0163] In one embodiment, the article of footwear is a shoe, and the main sole material is selected from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPUs), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester.

[0164] Preferably, the mass fraction of the main sole material is greater than or equal to 55% and less than or equal to 70%.

[0165] Preferably, the mass fraction of the first auxiliary sole material is greater than or equal to 5% and less than or equal to 35%, in particular greater than or equal to 10% and less than or equal to 30%.

[0166] In one embodiment, the main sole material is selected from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPUs), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester; preferably a styrenic thermoplastic elastomer, preferably SEBS or SBS, and the sole comprises a first auxiliary sole material selected from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester;preferably a styrenic thermoplastic elastomer (different from the main sole material), preferably SEBS or SBS. The sole may comprise a second auxiliary sole material which is a polyolefin, for example PP or PE.;

[0167] In one embodiment, the main sole material is a vulcanized thermoplastic elastomer, optionally the sole further comprises a first auxiliary sole material, in particular a styrenic thermoplastic elastomer, for example SEBS or SBS, optionally grafted.

[0168] Preferably, the mass fraction of the main sole material in the sole is greater than or equal to 40% and less than or equal to 85%, more preferably greater than or equal to 30%, preferably greater than or equal to 40%, in particular greater than or equal to 55%.

[0169] Preferably, the mass fraction of the first auxiliary sole material in the sole is greater than or equal to 8%, more preferably less than or equal to 30%, for example between 15% and 25%.

[0170] In one embodiment, the main sole material is polypropylene.

[0171] Preferably, the mass fraction of the main sole material in the sole is greater than or equal to 50%, more preferably greater than or equal to 80%, in particular greater than or equal to 90%, for example of the order of 100%.

[0172] Preferably, when the sole comprises one or more auxiliary sole material(s), the latter is / are preferably embedded, like one or more fillers, in a polymer matrix formed by the main sole material.

[0173] The sole according to the invention may be / may comprise a wear sole or a midsole or a combination thereof.

[0174] In one embodiment, the article of footwear comprises an outsole and a midsole, in particular the midsole is a removable insole.

[0175] The midsole can be removably arranged in a foot-receiving space of the footwear article so as to come under the user's foot.

[0176] The midsole can also act as a sockliner.

[0177] The sole according to the invention may comprise (be made up of) one or more sole components comprising (in particular made up of) said main sole material and / or one or more auxiliary sole materials. A sole component may be a wear sole, a midsole, an insole, a cushioning heel component (for example a donut), a textile component (as defined above with reference to the upper), a functional device providing stability, or a reinforcing or cushioning insert, or a cellular component, in particular a foam or a set of foamed and possibly agglomerated and / or glued beads.

[0178] In one embodiment, the sole comprises / is a midsole comprising an outer face coming into direct contact with the ground.

[0179] Advantageously, the midsole is configured to perform the function of an outsole. The footwear article therefore does not include an outsole.

[0180] The midsole is preferably a one-piece component.

[0181] It is preferable to choose a foam midsole with good abrasion resistance.

[0182] In one embodiment, the sole comprises an outsole component, preferably comprises (or is) an outsole, having a density (g / cm3) greater than or equal to 0.85; preferably less than or equal to 1.30.

[0183] In one embodiment, the sole comprises a midsole component, preferably comprises (or is) a midsole, having a density (g / cm3) greater than or equal to 0.10; preferably less than or equal to 0.90; more preferably having a density less than or equal to 0.50; in particular less than or equal to 0.40.

[0184] In one embodiment, the sole comprises a midsole component, preferably comprises (or is) a midsole, having a density (g / cm3) greater than 0.50 and less than or equal to 0.85; in particular less than or equal to 0.75.

[0185] In one embodiment, the footwear article comprises an injected outsole, in particular comprising the main sole material (e.g., optionally grafted SEBS) and optionally a first auxiliary sole material (e.g., PP or PE), and an injected midsole, in particular directly onto the outsole still in a softened state.

[0186] The midsole comprises the main sole material (e.g. SEBS, possibly grafted) and possibly the first auxiliary sole material (e.g. PP or PE), mixed with at least one foaming agent. The outsole and the midsole are manufactured by bi-injection.

[0187] In one embodiment, the shoe comprises a footbed, in particular arranged in the foot receiving space of the shoe so as to come under the foot when the shoe is worn. The footbed is preferably removable.

[0188] This arrangement is advantageous when the sole is injected onto the upper. Indeed, when a sockliner is already present during the injection process, it can be crushed and thus lose its foot-friendly properties. The use of a removable sockliner can overcome this problem.

[0189] The insole may advantageously comprise agglomerated foam beads, more preferably said foam beads comprise (in particular are) a material chosen from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester, or a combination thereof.

[0190] The insole may in particular comprise a foam comprising a polyolefin, in particular a polyethylene. Said foam may be laminated with a textile, optionally between two textiles. Said textile(s) comprising polyolefin threads and / or fibres.

[0191] Main and / or auxiliary material(s) of upper and / or sole

[0192] Polyolefins

[0193] The polyolefin(s) cited in this text, in particular for the main upper material and / or the main sole material and / or the auxiliary upper and / or sole material(s), is / are chosen from homopolymers of polyolefins, optionally grafted, copolymers or terpolymers of polyolefins, optionally grafted.

[0194] Polyolefin copolymers comprise two olefinic repeating units, optionally grafted.

[0195] Polyolefin terpolymers comprise three or more olefinic repeating units, optionally grafted.

[0196] The olefinic repeating units preferably comprise units derived from alkenes, particularly ethylene or propylene.

[0197] The polyolefin(s) used in the present invention is / are by definition thermoplastic.

[0198] By grafted is understood one or more functions or one or more grafted groups which may be one or more alkyl groups, linear or branched, comprising from 1 to 10 carbon atoms, preferably from 1 to 5 carbon atoms, for example a methyl group, an ethyl or propyl group, or one or more ester functions, for example an alkyl ester whose alkyl group comprises from 1 to 5 carbon atoms, or one or more acrylate (RO-CO-CH=CH2) or acryloyl (H2C=CH-CO-R) functions, in particular R is an alkyl group comprising from 1 to 10 carbon atoms.

[0199] The polyolefin(s) cited in the present text, in particular for the main upper material and / or the main sole material and / or the auxiliary upper and / or sole material(s), is / are preferably chosen from a list I comprising (in particular consisting of) polypropylene; polyethylene, in particular high density polyethylene, very high density polyethylene, low density polyethylene, and very low density polyethylene (LLDPE); polymethylpentene (PMP), polybutene-1 (PB-1), polyisobutene; preferably from polypropylenes and polyethylenes, in particular the polyethylene is chosen from high density polyethylene, very high density polyethylene, low density polyethylene, and very low density polyethylene (LLDPE).

[0200] The polyolefin(s) cited in this text, in particular for the main upper material and / or the main sole material and / or the auxiliary upper and / or sole material(s), may also be chosen from a list II comprising (in particular consisting of) poly(ethylene-vinyl acetate) (EVA) (in particular resulting from the copolymerization of ethylene and vinyl acetate, it is a copolymer of olefins), in particular not crosslinked; ethylene-polyvinyl alcohol.

[0201] The polyolefin(s) cited in this text for the main sole material and / or the auxiliary sole material(s) may be chosen from olefin-based mineral oils, such as poly-alpha-olefins, in particular which are plasticizers for styrenic thermoplastic elastomers.

[0202] The polyolefin can be a bio-sourced or petro-sourced polyolefin, in particular bio-sourced, i.e. derived from renewable material(s), for example it can be a bio-sourced polyethylene derived from sugar cane.

[0203] Bio-sourced material means any material derived from renewable material(s), as opposed to petroleum-sourced material.

[0204] The bio-sourced polyolefin can have a so-called direct origin, i.e. it comes directly from renewable material(s), or an indirect origin, i.e. it comes from a mixture of renewable material(s) and petroleum-based material(s) and / or recycled material(s). In the latter case, the polyolefin is defined by obtaining a certificate established according to the "mass balance approach" principle defining the proportion of recycled and / or bio-sourced material(s) used to obtain it.

[0205] Olefinic thermoplastic elastomers

[0206] One or more olefinic thermoplastic elastomers cited in this text, in particular for the main upper material and / or the main sole material and / or the auxiliary upper and / or sole material(s), is / are chosen from:

[0207] - polyisobutylenes (PIB); and / or

[0208] - terpolymers of ethylene, propylene, and diene (EPDM); copolymers of ethylene and propylene; copolymers of ethylene and alpha-olefin(s), for example copolymers of ethylene and butene or copolymers of ethylene and octene, and a mixture thereof; preferably EPDM and copolymers of ethylene and propylene; and / or

[0209] - mixtures of a polyolefin, in particular polypropylene, with one or more unvulcanized olefinic thermoplastic elastomer(s), and optionally one or more plasticizers (for example mineral or naphthenic or paraffinic oil(s)), 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 copolymers of ethylene and butene or copolymers of ethylene and octene).

[0210] Vulcanized thermoplastic elastomers

[0211] One or more vulcanized thermoplastic elastomers (TPE-V) cited in this text, in particular for the main upper material and / or the main sole material and / or the auxiliary upper and / or sole material(s), is / are preferably:

[0212] - a mixture of a vulcanized olefinic elastomer (in particular forming the rubber phase) and a polyolefin (in particular as defined in this text, more particularly forming the thermoplastic phase), in particular polypropylene, or

[0213] - a mixture of a vulcanized olefinic elastomer (in particular as defined in this text and vulcanized, more particularly forming the rubber phase) and a styrenic thermoplastic elastomer (in particular as defined in this text, more particularly forming the thermoplastic phase), in particular SEBS or SBS.

[0214] Vulcanization generally takes place during the extrusion-granulation step. Preferably, the highly vulcanized rubber phase is dispersed in the thermoplastic phase. This elastomer has the advantage of exhibiting good adhesion to olefinic polymers, such as polypropylene and polyethylene. This vulcanization is known in the state of the art as dynamic vulcanization during which the elastomer is vulcanized during its melt mixing with a suitable thermoplastic polyolefin.

[0215] Said vulcanized olefinic elastomer is preferably chosen from ethylene, propylene, and diene terpolymers (EPDM); ethylene and propylene copolymers; ethylene and alpha-olefin(s) copolymers, for example ethylene and butene copolymers or ethylene and octene copolymers, and a mixture thereof; preferably EPDM and ethylene and propylene copolymers. In the present text, polyurethanes are not considered to be vulcanized thermoplastic elastomers.

[0216] Styrenic thermoplastic elastomers

[0217] One or more styrenic thermoplastic elastomers cited in the present text, in particular for the main upper material and / or the main sole material and / or the auxiliary upper and / or sole material(s), is / are preferably chosen from thermoplastic elastomers comprising styrenic repeating units (TPE-S) (in particular a styrene group: -CH(C6H5)-CH2), more preferably from thermoplastic elastomers comprising one or more styrenic blocks and optionally one or more olefin blocks (optionally grafted), preferentially 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.

[0218] A styrenic thermoplastic elastomer according to the invention can be grafted, for example SEBS can be grafted, for example with one or more acid anhydrides, such as maleic anhydride, and / or one or more carboxylic acids and / or one or more vinyl functions.

[0219] The grafting of the styrenic thermoplastic elastomer has the function of improving the adhesion of the sole, for example the outsole, to another sole, for example a midsole, and / or to the upper when the sole is injected directly onto the upper.

[0220] Advantageously, the thermoplastic elastomers selected within the scope of the present invention have better processability and a lower associated energy cost than thermosetting elastomers by conventional thermoplastic processes such as injection molding, extrusion, thermoforming, blow molding, etc.

[0221] Examples include polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPUs), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester.

[0222] Definitions

[0223] Advantageously, the main upper material and / or the main sole material, and optionally one or more auxiliary upper material(s) and / or one or more auxiliary sole material(s), has or have (in particular each) a melting temperature (Tf) and / or a glass transition temperature (Tg), in particular said melting temperature(s) is / are higher than said glass transition temperature(s).

[0224] In this text, footwear means any item of footwear not including boots.

[0225] In this text, the term "boot" is understood to mean a rain or snow boot or a clog, in particular an article of footwear comprising an upper and a sole portion comprising a common polymer material forming a majority by mass of the upper and the sole, said upper and the sole being molded together.

[0226] In this text, thermoplastic material is understood to mean any material capable of being softened or melted by heating, sufficiently, without degradation of the latter, so that it can be used in a process for transforming a plastic, such as those mentioned above, and several times.

[0227] By mass majority of the stem we mean:

[0228] - the mass fraction of said main rod material measured relative to the total mass of the rod is greater than the mass fraction of any other material comprising the rod; or

[0229] - the mass fraction of said main rod material plus the respective mass fraction(s) of the auxiliary rod material(s), measured relative to the total mass of the rod, is greater than the mass fraction of any other material included in the rod and not chosen from the main list defined in this text; or

[0230] - the fraction of surface area occupied by the main rod material measured in relation to the total surface area of ​​the rod is greater than the fraction of surface area occupied by any other material comprising the rod; or

[0231] - the surface fraction occupied by the main rod material plus the respective surface fraction(s) of the auxiliary rod material(s), measured relative to the total surface area of ​​the rod, is greater than the surface fraction occupied by any other material included in the rod and not chosen from the main list defined in this text.

[0232] The main rod material, and possibly the auxiliary rod material(s) may thus represent, for example, 30%, 40% or even 50% or 60% by mass of the rod or the outer surface of the rod.

[0233] Main rod material means that the mass or surface fraction of the main rod material is greater than the mass or surface fraction of any auxiliary rod material, and possibly greater than the mass or surface fraction of any other material included in the rod not chosen from the main list defined in this text.

[0234] Where the main upper material represents, for example, 30% by mass of the upper, the auxiliary material(s) represent(s) (each) less than 30% by mass of the upper. The outer surface of the upper is preferably calculated from a flat projected upper. This may be, for example, the surface of the upper pattern before it is shaped in three dimensions by sewing, but including all the upper components arranged along its outer surface.

[0235] Total mass of the upper is understood to mean the mass of the upper on the finished shoe with all its components.

[0236] By mass majority of the sole we mean:

[0237] - the mass fraction of said main sole material, measured relative to the total mass of the sole, is greater than the mass fraction of any other material comprising the sole; or

[0238] - the mass fraction of said main sole material added to the respective mass fraction(s) of the auxiliary sole material(s), measured relative to the total mass of the sole, is greater than the mass fraction of any other material included in the sole not chosen from the main list defined above in this text.

[0239] The main sole material, and possibly the auxiliary sole material(s), may thus represent 40% or even 50% or 60% by mass of the sole.

[0240] Main sole material is understood to mean that the mass fraction of the main sole material is greater than the mass fraction of any auxiliary sole material, and possibly greater than the mass fraction of any other sole material not chosen from the main list defined in this text.

[0241] For example, where the main sole material represents 30% by mass of the sole, the auxiliary material(s) represent (each) less than 30% by mass of the sole.

[0242] In this text, the mass fraction of a main or auxiliary rod material in the rod is the ratio of the mass (g) of said main or auxiliary rod material to the total mass (g) of the rod.

[0243] For the calculation of the total mass of the upper in order to define the mass fraction(s) of main upper material(s) and / or auxiliary upper material(s), the entire upper material(s) covering the top of the foot, i.e. arranged above the foot's support plane, is considered. Any sole material(s) connected to the upper (sole part of a knitted sock, for example) is / are counted as part of the sole, in particular the midsole or the outsole.

[0244] In this text, the fraction of surface area occupied by the main or auxiliary rod material in the rod is the ratio of the occupied surface area (cm2 ) by said material visible on the total exterior surface (cm 2 ) of the upper projected flat, the outer surface of the upper being that oriented towards the outside of the shoe.

[0245] In this text, the mass fraction of a main or auxiliary sole material in the sole is the ratio of the mass of said main or auxiliary material to the total mass of the sole.

[0246] When a first upper component comprises the main upper material and a second upper component comprises said main upper material, the first component and the second component each comprise a main upper material in a same base polymer, which may be selected from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPUs), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester; and in particular a polyolefin, for example PP or PE.The basic polymer material of the first component may, however, be different from the basic polymer material of the second component in terms of hardness or its intrinsic properties (molar mass, degree of polymerization, quantity of monomer(s)) or its presentation (foam, textile, foamed beads, etc.).

[0247] The footwear article, in particular the upper and / or the sole, may comprise approximately 20% at most, in particular 15% at most, more particularly 10% at most, in particular 5% at most, by mass relative to its total mass, of one or more contaminating material(s), i.e. which is / are not chosen from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, and vulcanized thermoplastic elastomers. Said contaminating material(s) may be chosen from polyurethanes, polyamides or polyesters (for example polyethylene terephthalate (PET), or polybutylene terephthalate (PBT)). These contaminating materials may come, for example, from recycled materials.

[0248] In a sub-alternative embodiment, the article of footwear is a boot. The boot comprises an outsole and an upper. The upper comprises a lower upper portion covering the foot, in particular the forefoot, the instep, the medial region, the lateral region, and the rearfoot. The upper also comprises an upper upper portion at least partially covering the leg.

[0249] Preferably, the lower part of the upper and the outsole are co-injected.

[0250] In the two preceding sub-variants, preferably, the main sole material is a styrenic thermoplastic elastomer, in particular a SEBS, and the main upper material is a styrenic thermoplastic elastomer, in particular a SEBS. The upper part of the upper comprises one or more foam(s) and one or more textile(s) in at least one auxiliary upper material, in particular chosen from polyolefins. The upper may also comprise one or more foam(s) and / or one or more textile(s) forming an internal liner arranged in the space receiving the foot of the boot and covering all or part of the internal face of the injected lower part of the upper.

[0251] Preferably, the mass fraction of the main sole material in the sole is greater than or equal to 45%, more preferably greater than or equal to 50%, in particular less than or equal to 70%.

[0252] The outsole may also comprise a first auxiliary sole material, which may be chosen from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester; and for example a polyolefin, in particular polypropylene.

[0253] The mass fraction of the first auxiliary sole material in the sole is greater than or equal to 5% and less than or equal to 40%, in particular less than or equal to 30%.

[0254] Preferably, the mass fraction of the main rod material is greater than or equal to 40%, more preferably less than or equal to 60%.

[0255] The rod may comprise a first rod auxiliary material which is a polyolefin, in particular polypropylene, the mass fraction of which in the rod is greater than or equal to 10%, preferably less than or equal to 35%.

[0256] Preferably, the ratio of the mass of the main rod material and the mass of the first auxiliary rod material to the total mass of the rod is greater than or equal to 60%, more preferably greater than or equal to 70%.

[0257] In an alternative embodiment, the main upper material is selected from one of the following materials: a polyolefin, an olefinic thermoplastic elastomer, or a vulcanized thermoplastic elastomer, preferably from a polyolefin or an olefinic thermoplastic elastomer, more preferably a polyolefin.

[0258] In an alternative embodiment, the main sole material is selected from one of the following materials: a styrenic thermoplastic elastomer, a polyolefin, or a vulcanized thermoplastic elastomer.

[0259] In an alternative embodiment, the main sole material is a styrenic thermoplastic elastomer.

[0260] In an alternative embodiment, the main sole material is a polyolefin, in particular polypropylene.

[0261] In an alternative embodiment, the rod comprises a yarn comprising a material selected from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPUs), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester.

[0262] Preferably, the polyolefin is polypropylene or polyethylene.

[0263] Preferably, the wire comprises the main rod material.

[0264] In an alternative embodiment, the upper comprises a textile component, and the textile component comprises a yarn comprising the main upper material, in particular the main upper material is selected from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester.

[0265] Preferably, the main upper material is polypropylene or polyethylene. In an alternative embodiment, the upper comprises a textile part forming a foot receiving area having an external face, and at least one part, in particular a band, comprising an olefinic thermoplastic elastomer, said part being secured to said external face of the textile part and to said sole.

[0266] Advantageously, the textile part forming a foot receiving area comprises a textile component, in particular comprising a thread comprising the main upper material chosen from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester; more particularly the main upper material is a polyolefin or an olefinic thermoplastic elastomer or a vulcanized thermoplastic elastomer.

[0267] Advantageously, the textile component may be as described in this text. Preferably, said part is a part of imitation leather.

[0268] Advantageously, said part comprises a textile support and a polymeric layer comprising, in particular consisting essentially of, more particularly consisting of a material chosen from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester; and in particular said olefinic thermoplastic elastomer, said polymeric layer being secured to said textile support. Also advantageously, the face of the part comprising the textile support is oriented opposite the external face of the textile part.

[0269] Preferably, the upper comprises one or more bands, more preferably arranged to run along, at least in part, at least one of the following edges of the shoe: the front edge, the medial edge, the lateral edge, and the rear edge.

[0270] Preferably, said part(s), in particular strip(s), is / are secured to the external face of the textile part forming a foot reception area, and to the sole.

[0271] Preferably, said part(s), in particular strip(s), has / have (in particular each) a thickness greater than or equal to 0.5 mm and less than or equal to 3 mm.

[0272] Preferably, said at least one part, in particular a strip, is secured to the external face of said textile part, and possibly to the sole, by fusion of at least one part of its structure.

[0273] Preferably, at least a portion of said at least one piece, in particular a strip, is arranged between the sole and the external face of the textile part for receiving the foot.

[0274] Advantageously, the olefinic thermoplastic elastomer makes it possible to form a reinforcing part, in particular a reinforcing strip, having a leatherette appearance, which is compatible with the polymer material(s) of the textile part and the sole so that it can be bonded by fusion.

[0275] In one embodiment, said part is arranged so as to form a covering part of all or part of the top of the foot, in particular comprises an opening for introducing the foot into said covering part.

[0276] In an alternative embodiment, the sole comprises a cellular component, in particular a foam, comprising a material selected from one of the following materials: polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, thermoplastic polyurethanes (TPUs), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester; and in particular a styrenic thermoplastic elastomer, an olefinic thermoplastic elastomer, or a polyolefin, preferably from one of the following materials: an olefinic thermoplastic elastomer, more preferably an olefinic thermoplastic elastomer.

[0277] Preferably, the foam beads are agglomerated into a block, in particular are glued together at their surfaces by fusion.

[0278] Preferably, the cellular component has a volume density of between 0.1 g / cm3 and 0.4 g / cm3, preferably between 0.15 g / cm3 and 0.25 g / cm3.

[0279] Preferably, the honeycomb component is a midsole. In an alternative embodiment, the upper comprises a front toe cap comprising the main upper material or an auxiliary upper material, and / or a rear counter comprising the main upper material or an auxiliary upper material.

[0280] The upper may include a rear counter or a front hard toe comprising, or made of, a material selected from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, thermoplastic polyurethanes (TPUs), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester.

[0281] The upper may thus comprise a rear counter or a front hard toe comprising, or consisting of, a styrenic thermoplastic elastomer, for example SEBS, optionally mixed with at least one polyolefin.

[0282] The upper may include a rear counter or a front hard toe comprising, or consisting of, a vulcanized thermoplastic elastomer.

[0283] In an alternative embodiment, the upper comprises at least one eyelet for passing at least one lacing element, said at least one eyelet for passing comprises a textile strip comprising at least one thread comprising the main upper material or an auxiliary upper material, in particular the main upper material is a polyolefin.

[0284] In an alternative embodiment, the upper comprises a foam component comprising the main upper material, in particular the main upper material is selected from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, thermoplastic polyurethanes (TPUs), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester.

[0285] The upper may comprise one or more complexes, a complex comprising a textile secured to said foam component, preferably the textile and the foam component comprise (in particular are made of) the main upper material, selected from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester; preferably made of polyolefin, for example PP or PE.

[0286] Said foam component, optionally assembled with a textile, may be arranged in the rear heel region of the upper in order to provide comfort and / or in a medial region of the upper and / or in a lateral region of the upper.

[0287] In an alternative embodiment, the upper and / or the sole each comprises a recycled material from a sole and / or the upper of another shoe, and / or a recycled material from a sole and / or the upper of a boot. The recycled material preferably comprises the main upper material and / or the main sole material and / or the auxiliary upper and / or sole material(s).

[0288] The other shoe may be a shoe according to the invention.

[0289] In an alternative embodiment, the mass of the main upper material, and optionally the mass of the auxiliary upper material(s), to the total mass of the upper is greater than or equal to 40%, preferably greater than or equal to 50%. In an alternative embodiment, the ratio of the mass of said main upper material and the mass of the auxiliary upper material(s), to the total mass of the upper is greater than or equal to 50%, and the main upper material and the auxiliary upper material(s) are selected from polyolefins and olefinic thermoplastic elastomers. In an alternative embodiment, the main sole material at least partially covers the upper, in particular the main upper material.

[0290] Preferably, the main sole material extends substantially over the forefoot region and / or the rearfoot region and / or the medial region and / or the lateral region of the upper.

[0291] In one variant, the main sole material is secured to the upper, in particular to the main upper material, without an intermediate bonding agent, for example without a bonding agent or without stitching. In one embodiment, the mass of the main sole material, and possibly the mass of the auxiliary sole material(s), of the total mass of the sole is greater than or equal to 40%, preferably greater than or equal to 50%.

[0292] In an alternative embodiment, the ratio of the mass of said main sole material and the mass of the auxiliary sole material(s) to the total mass of the sole is greater than or equal to 50%, and the main sole material and the auxiliary sole material(s) are selected from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester.

[0293] In an alternative embodiment, the article of footwear, in particular the shoe, in particular a sports shoe, or the upper and / or the sole of the article of footwear, in particular of said shoe, comprises / comprise (in particular each):

[0294] - at most 10% by mass of one or more contaminating material(s) not chosen from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester,

[0295] - in particular at most 10% by mass of one or more thermoplastic contaminating material(s) and / or at most 5% by mass of one or more thermosetting contaminating material(s).

[0296] For example, if the contaminating material(s) is / are made of thermoplastic contaminating material(s), the mass fraction of contaminant(s) in the shoe is 10% at most.

[0297] For example, if the footwear comprises 5% by mass of one or more thermosetting contaminant material(s), said footwear may still comprise at least 5% by mass of one or more thermoplastic contaminant material(s).

[0298] In an alternative embodiment, the article of footwear, in particular the shoe, in particular a sports shoe, or the upper and / or the sole of the article of footwear, in particular the shoe, comprises / comprise (in particular each):

[0299] - one or more contaminating material(s).

[0300] In an alternative embodiment, the article of footwear, in particular the shoe, in particular a sports shoe, or the upper and / or the sole of the article of footwear, in particular the shoe, comprises / comprise (each):

[0301] - at most 10% by mass of one or more contaminating material(s),

[0302] - in particular at most 10% by mass of one or more thermoplastic contaminating material(s) and / or at most 5% by mass of one or more thermosetting contaminant(s).

[0303] In this text, the term thermosetting material, in particular contaminating thermosetting material, is understood to mean any material which does not have a hot transformation temperature by a plastic shaping process, for example by extrusion-injection, extrusion-blowing, hot pressing (thermocompression), extrusion-spinning.

[0304] In this text, the term thermoplastic material, in particular thermoplastic contaminant material, is understood to mean any material having a hot transformation temperature by a plastic shaping process, for example by extrusion-injection, extrusion-blowing, hot pressing, extrusion-spinning.

[0305] The inventors have advantageously determined that contaminant levels, depending on whether they are thermoplastic or thermosetting, must not exceed certain proportions in the footwear article so that the latter can be recycled without separation of its different components and so that the final recycled material has satisfactory mechanical properties in many new applications.

[0306] A non-exhaustive explanation, particularly with respect to thermosetting contaminants, is that the contaminating material(s) is / are arranged as nodules in the thermoplastic matrix derived from the main materials, and possibly auxiliary materials, of the upper and sole. In addition, the inventors have determined that the properties of the polymeric mixture derived from a footwear article can be surprisingly improved by a contaminating material.

[0307] In particular, the abrasion resistance of the mixture is surprisingly improved when the shoe includes one or more contaminating material(s) made of polyurethane or polyamide, in particular whose mass fraction is at most 10% in the shoe (see table in attached figure 5). Beyond 10%, it has been observed that the abrasion resistance decreases.

[0308] The mass fraction of contaminating material(s) in the footwear item is preferably greater than or equal to 0.5%, more preferably greater than or equal to 1%.

[0309] In an alternative embodiment, the article of footwear, in particular the shoe, in particular a sports shoe, or the upper and / or the sole of the article of footwear, in particular the shoe, comprises / comprise (in particular each) a foam in a contaminating material.

[0310] In one embodiment, the sole or upper comprises a foam in a contaminant material which represents at least 30% by volume, preferably at least 40% by volume, more preferably at least 50% by volume, preferentially at least 60% or 70% by volume, of said sole or said upper.

[0311] In one embodiment, said foam in a contaminating material represents at most 10% by mass of the footwear article, in particular the shoe, when the contaminating material is thermoplastic, and / or at most 5% by mass of the footwear article, in particular the shoe, when the contaminating material is thermosetting.

[0312] Said foam may be a foamed block or comprise expanded particles agglomerated together.

[0313] For example, the density of a polyurethane foam ranges from 0.040 kg / litre to 0.4 kg / litre, for example around 0.055 kg / litre, whereas the density of a styrenic thermoplastic elastomer, such as SEBS, is greater than or equal to 0.80 kg / litre.

[0314] In an embodiment specific to polyesters, the invention relates to an article of footwear, in particular a shoe, more particularly a sports shoe, advantageously comprising, more advantageously consisting essentially of, even more advantageously consisting of:

[0315] - a rod, a majority by mass of the rod or a majority of the surface of the rod being made of a main rod material, the rod optionally further comprising one or more auxiliary rod material(s);

[0316] - a sole, a majority by mass of the sole being made of a main sole material, the sole optionally further comprising one or more auxiliary sole material(s); and characterized in that the main upper material, and optionally the auxiliary upper material(s), is / are selected from polyesters and materials chemically compatible with polyesters; and in that the main sole material, and optionally the auxiliary sole material(s), is / are selected from polyesters and materials chemically compatible with polyesters.

[0317] The main upper material may comprise at least one of the following materials: a thermoplastic copolyester, polyethylene terephthalate.

[0318] The thermoplastic copolyester may be a block copolymer comprising rigid polyester segments and flexible polyether and / or polyester segments, and in particular TPEE or TPC-ET.

[0319] The upper may comprise a lower portion comprising a thermoplastic copolyester which is a block copolymer comprising rigid segments of polyester and flexible segments of polyether and / or polyester, and in particular TPEE or TPC-ET.

[0320] The upper may include an upper portion that comprises polyethylene terephthalate or a thermoplastic copolyester that is a block copolymer comprising rigid segments of polyester and flexible segments of polyether and / or polyester, e.g., TPEE.

[0321] The upper portion may comprise a top layer of polyethylene terephthalate, a bottom layer of polyethylene terephthalate, a central layer of thermoplastic copolymer and surrounded upwardly and downwardly by an intermediate layer of adhesive, including an upper intermediate layer disposed between the central layer and the top layer, and a lower intermediate layer disposed between the central layer and the bottom layer. The intermediate layers of adhesive make it possible to bond the different layers together. The intermediate layer of adhesive may be of polyethylene terephthalate.

[0322] The upper may include a polyethylene terephthalate lace.

[0323] The upper may include lacing eyelets, for example made in the form of a thread embroidered on the upper. The lacing eyelets may be made of polyethylene terephthalate.

[0324] The upper may include a non-woven polyethylene terephthalate upper reinforcement.

[0325] The upper may include a non-woven polyethylene terephthalate tab.

[0326] The footwear article may include, at the rear of the footwear article and above a midsole, a thermoplastic copolyester reinforcement ring.

[0327] The main sole material may comprise at least one of the following materials: a thermoplastic copolyester, a thermoplastic vulcanizate (TPV) type thermoplastic elastomer comprising a soft phase and a thermoplastic phase of thermoplastic copolyester.

[0328] The thermoplastic elastomer of the thermoplastic vulcanizate (TPV) type may comprise a soft phase of poly(styrene / butadiene) and a thermoplastic phase of block copolymer comprising rigid segments of polyester and soft segments of polyether and / or polyester. The thermoplastic phase may thus be TPEE.

[0329] The sole may comprise a midsole comprising a block copolymer comprising rigid polyester segments and flexible polyether and / or polyester segments, and in particular TPEE or TPC-ET.

[0330] The sole may comprise an outsole comprising a thermoplastic vulcanizate (TPV) comprising a soft poly(styrene / butadiene) phase and a thermoplastic block copolymer phase comprising rigid polyester segments and soft polyether segments, and in particular a thermoplastic TPEE phase.

[0331] Alternatively, the sole may comprise a rubber outsole. In this case, the outsole is advantageously fixed to the midsole using a specific bonding primer, which, when subjected to heat, allows the outsole to be easily disassembled for recycling the shoe.

[0332] Finally, concerning this embodiment dedicated to polyesters as the main material, the footwear article may comprise an insole comprising a block copolymer comprising rigid segments of polyester and flexible segments of polyether and / or polyester, and in particular TPEE or TPC-ET.

[0333] It is sometimes necessary to use certain materials to provide particular functionalities to the footwear article, in particular when it is a sports shoe. The variant embodiments and embodiments according to a first aspect of the invention can be combined independently with each other.

[0334] The injected sole can be a outsole or a midsole or a combination of these.

[0335] In a first embodiment, the sole is injected directly onto the upper. Preferably, the upper is arranged on a foot-shaped preform, then the sole is injected onto the lower part of the upper. The lower part of the upper may be a mounting insole in connection with the lower edges of the upper (for example when the upper is shaped in three dimensions using welding(s) and / or stitching(s) to cover the foot) and / or the textile sole part of a textile upper component. The textile upper component may be a flat textile component, shaped in three dimensions so as to form a foot-supporting liner, for example by sewing / welding. The textile upper component may be a knitted sock comprising an integrated knitted sole part, in particular heat-melted or heat-compressed.

[0336] Preferably, the bonding is carried out between the upper and the sole without a bonding agent.

[0337] The main and / or auxiliary sole and upper materials selected in the present invention allow a sole to be manufactured by injecting it directly onto an upper without adhesion problems, thus simplifying the process and reducing the number of different materials used.

[0338] Preferably, the main sole material is selected from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester.

[0339] The applicant observed that this main sole material has very good adhesion to the main upper material, particularly when it is a polyolefin or an olefinic thermoplastic elastomer.

[0340] The mixture injected to manufacture the sole may include, in addition to the main sole material, a plasticizer and / or a filler (for example calcium carbonate) and / or one or more foaming agents (for example if it is the midsole).

[0341] The plasticizer can be chosen from mineral oils and / or naphthenic or paraffinic oils.

[0342] The sole injected onto the upper can be a outsole or a midsole. In the latter case, at least one foaming agent is used in a mixture with the main sole material.

[0343] In one variant, the method comprises a step of treating at least part of the surface of the sole, in particular the outsole and / or the midsole, and / or at least part of the surface of the upper, in particular the surface of one or more textile component(s), so as to improve the adhesion of the sole to the upper and / or of the outsole to the midsole and / or of a functional component (for example a lateral reinforcement, a hard front toe or a rear counter) to the textile component(s) of the upper.

[0344] Said treatment step comprises a light abrasion step (notably referred to as “buffing treatment” in English), and / or a plasma treatment step, and / or a flame treatment step, and / or a corona treatment step.

[0345] This step makes it possible to join two components together, possibly without a bonding agent. This avoids the addition of material that could end up as a contaminant in subsequent recycling processes. In one variant, the main sole material, and possibly the auxiliary sole material(s), is / are derived at least in part from the recycling of at least one other shoe or at least one boot, in particular at least one item of footwear according to any of the variant embodiments or embodiments according to the first aspect of the invention.

[0346] In one variant, the method comprises a step of foaming a foam component comprising the main sole material or at least one auxiliary sole material onto the injected sole in a softened state so as to at least partially secure said foam component to said sole, in particular without a bonding agent.

[0347] Bi-injection can be performed as described above.

[0348] The bonding between the foam component and the sole is carried out when the injected sole is in a softened state, i.e. before it is cooled to room temperature.

[0349] The subject of the present invention, according to another aspect, is a method for recycling at least one item of footwear, in particular a shoe, comprising the collection of at least one item of footwear, in particular a shoe, according to any one of the variants and embodiments according to a first aspect of the invention, or obtained by implementing the manufacturing method according to any one of the variants and embodiments according to a second aspect of the invention, and the transformation of said at least one item of footwear, in particular said shoe, into thermoplastic granules.

[0350] The footwear item, in particular the shoe, collected is in a first step crushed so as to obtain crushed materials, in particular having at least one dimension of the order of at least 1 mm to 40 mm. Said crushed materials are conveyed into an extrusion-granulation device to obtain thermoplastic granules. They may first undergo a washing step in order to remove dust.

[0351] In this text, thermoplastic granules are understood to mean any granule having a hot transformation temperature by a plastic(s) shaping process, for example by extrusion-injection, extrusion-blowing, hot pressing, extrusion-spinning, injection with supercritical fluid.

[0352] Said thermoplastic granules thus behave like a thermoplastic material when they are used in a hot transformation process, even if they include one or more thermosetting materials but in small quantities so as not to alter their ability to be transformed like thermoplastics.

[0353] Preferably, the extrusion-granulation device is / comprises a twin-screw extruder. Advantageously, this type of extruder allows for better mixing of the ground material. Advantageously, it is not necessary to separate the different components of the footwear article, in particular the shoe, because the latter are compatible with each other for their implementation in thermoplastic material transformation processes.

[0354] In an alternative embodiment, the transformation step comprises, in particular in this order:

[0355] - a step of grinding said footwear item, in particular said at least one shoe (in particular sports shoe), to obtain ground particles;

[0356] - a step of compacting said ground particles to obtain ground and compacted particles, in particular cold or hot,

[0357] - a step of extrusion-granulation of said crushed and compacted particles to obtain granules which can be transformed by a hot transformation process of plastic(s).

[0358] Advantageously, the compacting step makes it possible to expel air from the foamed and / or hollow recycled material(s).

[0359] Preferably, the compacting step is carried out hot by heating said ground particles, in particular to a temperature greater than or equal to 60°C and less than or equal to 110°C, for example of the order of 70°C to within + / - 10°C. In a variant, the recycling method comprises a step of hot transformation of at least a portion of said thermoplastic granules for the manufacture of a plastic part, in particular forming at least in part an article for practicing a sport.

[0360] In this text, a plastic part forming at least in part an article for practicing a sport is understood to mean that said part can form only part or substantially all of a sporting article.

[0361] Said plastic part comprises one or more recycled material(s), in particular originating from said recycled thermoplastic granules, chosen from polyolefins, olefinic thermoplastic elastomers, styrenic thermoplastic elastomers and vulcanized thermoplastic elastomers, optionally mixed with one or more other petro-sourced and / or bi-sourced and / or recycled and / or non-originating material(s) from the recycling process according to the invention.

[0362] Said plastic part is advantageously a fin blade, or a fin comprising a fin blade and a foot receiving housing.

[0363] The plastic part can be a handle, a zipper tip, a wheel, a lamp casing, or even a snorkel tip.

[0364] The plastic part is not limited to recycling in a sports article but can be implemented in any application for which the composition of the recycled footwear article has satisfactory mechanical properties.

[0365] In this text, the term "plastic" means any material based on the use of one or more (co)(ter)polymer(s) transformed by a hot process such as extrusion-injection, extrusion-molding, extrusion-blowing, thermocompression, or any equivalent technique.

[0366] The present invention relates, according to a final aspect, to a plastic part (in particular molded, more particularly of unitary molded construction), in particular forming at least in part an article for practicing a sport, capable of being obtained by the recycling process according to any one of the variant embodiments according to a third aspect of the invention, in particular said part is a fin blade or a fin comprising a fin blade and a foot receiving housing.

[0367] In one embodiment, said part is a fin blade or a fin comprising a fin blade and a foot receiving housing, and said part comprises a majority material by mass chosen from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester, preferably chosen from styrenic thermoplastic elastomers.

[0368] By majority material by mass, we understand that the mass fraction of said material is the highest of the material(s) entering into the composition of said part.

[0369] In one embodiment, said part comprises a majority material by mass chosen from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester, the mass fraction of said majority material by mass in said part is greater than or equal to 10%, preferably greater than or equal to 25%, more preferably greater than or equal to 35%, preferentially greater than or equal to 45%, in particular greater than or equal to 55%.

[0370] In one embodiment, the mass fraction of said recycled thermoplastic granules in the plastic part is greater than or equal to 10%, preferably greater than or equal to 25%, more preferably greater than or equal to 35%, preferably greater than or equal to 45%, in particular greater than or equal to 55%, possibly greater than or equal to 80% or 90%.

[0371] In another embodiment, said part comprises a recycled material chosen from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester, preferably chosen from styrenic thermoplastic elastomers, the mass fraction of said recycled material in said part is less than or equal to 25%, preferably less than or equal to 20%, more preferably less than or equal to 15%. In one embodiment, the mass fraction of said recycled thermoplastic granules in the plastic part is less than or equal to 25%, preferably less than or equal to 20%, more preferably less than or equal to 15%.

[0372] According to one aspect, the invention also relates to an item of footwear, for example a shoe, and in particular an item of footwear for practicing a sport, obtained by the method according to one of the embodiments described above.

[0373] According to another aspect, the invention relates to a device for manufacturing at least one part of a footwear article, the device comprising a mold defining an open cavity, a shape of at least one part of the cavity corresponding to a shape of a sole of the footwear article, the cavity being configured to receive, via at least one injection channel opening into the cavity, a mixture comprising a molten material and a supercritical fluid, a rim of an opening of the open cavity being configured to be placed in contact with a docking zone of a surface of at least one part of an upper of the footwear article, so that the surface of the at least one part of the upper ensures a closure of the cavity at the contact between the docking zone and the rim, so that said device is thus configured to implement the method according to one of the embodiments described above.

[0374] According to one embodiment, the device further comprises a cover configured to be placed on the mold so as to form with the mold a closed volume comprising the cavity, and a complementary part of the cavity in said closed volume, the at least one part of the upper of the footwear article being located inside said closed volume, the complementary part and the cavity being located on either side of the closure of the cavity at the contact between the docking zone and the rim, the device thus being configured to implement the method according to one of the implementation modes described above.

[0375] According to one embodiment, the device further comprises a support having a shape corresponding to a shape of a foot, an external surface of the support being configured to be covered with the at least one portion of the upper of the footwear article, the at least one portion of the surface of the at least one portion of the upper covering a portion of the external surface of the support corresponding to a sole of said foot.

[0376] For a better understanding, an embodiment and / or implementation of the invention is described with reference to the attached drawings representing, by way of non-limiting example, an embodiment or implementation respectively of a device and / or a method according to the invention. The same references in the drawings designate similar elements or elements whose functions are similar.

[0377] [Fig. 1] is a perspective view of a mold, in one part, of the cover corresponding to the mold, and of a shoe upper mounted on a support, before the step of placing the upper on the rim of the mold cavity, according to an embodiment of the invention

[0378] [Fig. 2] is a perspective view of a mold, in three parts, of the cover corresponding to the mold, and of a shoe upper mounted on a support, before the step of placing the upper on the rim of the mold cavity, according to an embodiment of the invention

[0379] [Fig. 3] is a perspective view of a mold, in one part, of the cover corresponding to the mold, and of a part of an upper of a shoe, before the step of placing the upper part on the rim of the mold cavity, according to an embodiment of the invention

[0380] [Fig. 4] is a perspective view of the part of the upper connected to a sole obtained after implementing the method according to one embodiment of the invention, and of the shoe obtained after implementing an additional step of assembling the part of the upper with another part of the upper.

[0381] [Fig. 5] is a sectional view of a rod with its support, placed on the mold, before the injection step, according to an embodiment of the invention; in this figure the mold cover is shown before its placement on the mold

[0382] [Fig. 6] is a sectional view of a rod with its support, placed on the mold, under a cover forming with the mold a closed pressurized space on either side of the edge of the mold cavity, before the injection step, according to the method of implementing the invention of figure 5

[0383] [Fig. 7] is a perspective view of a rod with its support, placed on the mold, before the injection step, according to the method of implementing the invention of Figures 5 and 6; in this figure the mold cover is shown before its placement on the mold

[0384] [Fig. 8] is a perspective view of the shoe obtained, with the upper support, after implementing the method according to the embodiment of the invention of Figures 5, 6, and 7.

[0385] [Fig. 9] is a perspective view of a rod support with a seal placed on an area of ​​the support corresponding to a docking area of ​​the surface of the part of the rod, according to the embodiment of the invention corresponding to figures 5, 6, 7 and 8 [Fig. 10] is a perspective view of a rod with an open surface at the part of the rod intended to be taken in the foamed material of the sole obtained according to an embodiment of the invention

[0386] [Fig. 11] is a perspective view of another upper with a solid surface at the level of the part of the upper intended to be taken in the foamed material of the sole obtained according to an embodiment of the invention

[0387] [Fig. 12] is a perspective view of another upper with a perforated surface at the part of the upper intended to be taken in the foamed material of the sole obtained according to an embodiment of the invention

[0388] [Fig. 13] is a perspective view of another upper with an openwork or textured surface near the docking zone at the level of the part of the upper intended to be taken in the foamed material of the sole obtained according to an embodiment of the invention

[0389] [Fig. 14] is a sectional view of a rod with its support, placed on a mold comprising several injection channels, before the injection step, according to an embodiment of the invention

[0390] [Fig. 15] is a sectional view of an upper with its support, placed on the mold, before the injection step, according to an embodiment of the invention in which an injection channel passes through the support of the upper. [Fig. 16] is a perspective view of inserts configured to be placed in the cavity of the mold so as to be associated with the sole obtained after overmolding with the foamed material, according to an embodiment of the invention.

[0391] [Fig. 17] is a sectional view of an upper with its support placed on the mold before the injection step, with the inserts placed in the mold cavity so as to be incorporated into the foamed material forming the sole, according to one embodiment of the invention. [Fig. 18] is a sectional view of an upper with its support placed on the mold, after the injection step, with the inserts placed in the mold cavity and incorporated into the foamed material forming the sole, according to one embodiment of the invention.

[0392] [Fig. 19] is a sequencing diagram of the steps of the method, according to one embodiment of the invention.

[0393] [Fig. 20] schematically illustrates in perspective a first example of a shoe which can be obtained by a method according to the invention.

[0394] [Fig. 21] represents the shoe of figure 20 according to the longitudinal section plane II-II shown in figure 20.

[0395] [Fig. 22] schematically illustrates in perspective a second example of a shoe which can be obtained by a method according to the invention.

[0396] [Fig. 23] schematically illustrates in perspective a third example of a shoe which can be obtained by a method according to the invention.

[0397] [Fig. 24] is a detailed sectional view of the shoe of Figure 23.

[0398] [Fig. 25] is a schematic representation of a contact surface of an insert, the contact surface comprising a texture comprising tubular or cylindrical patterns.

[0399] [Fig. 26] is a schematic representation of a contact surface of an insert, the contact surface comprising a texture comprising linear patterns.

[0400] [Fig. 27] is a schematic representation of a contact surface of an insert, the contact surface comprising a texture comprising tubular or cylindrical patterns in the center of the surface, and a linear pattern around the periphery of the surface.

[0401] [Fig. 28] is a perspective representation of a mold according to an exemplary embodiment.

[0402] [Fig. 29] is a sectional representation of the mold according to the embodiment example of Figure 28.

[0403] [Fig. 30] is a sectional representation of the steps of closing and opening the mold according to the embodiment example of Figure 28.

[0404] [Fig. 31] is a sectional representation of the closing and opening steps of a variant of the mold according to the embodiment of Figure 28.

[0405] [Fig. 32] is a sectional view of a rod with its support, placed on the mold, under a cover forming with the mold a closed pressurized space on either side of the rim of the mold cavity, with a complementary cavity pressurization channel, according to the embodiment of the invention illustrated in Figure 6.

[0406] [Fig. 33] is a sectional view of a rod with its support, placed on the mold, under a cover forming with the mold a closed pressurized space on either side of the rim of the mold cavity, with a pressurization channel for the cavity and the complementary cavity, according to the embodiment of the invention illustrated in Figure 6.

[0407] [Fig. 34] is a sectional view of a rod with its support, placed on the mold, under a cover forming with the mold a closed pressurized space on either side of the edge of the mold cavity, with several pressurization channels of the cavity matched with the through holes of an insert placed at the level of the external sole, according to the mode of implementation of the invention illustrated in figure 6

[0408] With reference to Figure 19, the invention relates to a method 100 for manufacturing at least a part of an article of footwear, for example a shoe 10, shown in Figures 4 or 8, using a step 107 of injecting, into a cavity 2 of a mold 1, a supercritical mixture comprising a molten thermoplastic material and a gas in a supercritical state, so as to foam the thermoplastic material in order to obtain satisfactory properties of a foamed material which forms a light and shock-absorbing sole 3 of the shoe 10; in particular, Figures 4 or 8 show the part of the shoe 10 obtained at the end of the method 100, with the part 9 of the upper taken from the foamed material of the sole 3. To obtain this result, the cavity 2 has at least in part a shape corresponding to the final shape of the foamed sole 3 which it is desired to obtain; this is illustrated in particular in figures 3 and 5.For example, the dimensions of the cavity shape are the dimensions on a scale between 1:0.98 and 1:1.02, and advantageously 1 to 1, of the shape of the sole of the footwear article.

[0409] In order to foam the molten thermoplastic material to obtain said foamed material which forms the sole 3, the method consists of pressurizing the cavity 2 of the mold 1, in particular by injecting a gas into said cavity 2, before injecting the supercritical mixture into the cavity 2, then depressurizing the cavity 2 in order to trigger expansion and foaming of the thermoplastic mixture in the cavity 2 in order to obtain the foamed material of the sole 3.

[0410] In order for a part 9 of the upper of the shoe 10 to be taken in said foamed material of the sole 3, said part 9 of the upper is suitably placed in the cavity 2 of the mold; for this purpose, as illustrated in Figures 3 and 5, the cavity 2 comprises an opening with a rim 5 on which is placed a zone 6, called docking zone 6, of a surface 7 of the part of the upper 9, so that the surface 7 of the part of the upper 9 ensures a closure of the cavity at the contact between the docking zone 6 and the rim 5.

[0411] In order to be able to put the cavity 2 of the mold 1 under pressure, in particular by injecting a gas into said cavity 2, it is then essential to ensure a sufficient seal, in particular against gas, of the closure of the cavity 2 at the level of the contact between the docking zone 6 and the rim 5; the thickness of the rod being variable, the rod being able to take complex shapes, with significant dimensional tolerances, it can be difficult to obtain the desired seal. A particularly advantageous solution can be the use of a counter pressure in the zone of the rod 9 which is not immersed in the cavity 2, i.e. in the zone of the rod which is on the other side of the closure relative to the cavity 2.In Figure 5 in particular, said area of ​​the rod 9 which is immersed in the cavity 2 is located in the lower part of the figure, and the part of the rod 9 which is not immersed in the cavity is located above the straight line joining the two points of the docking area 6, designated by the references 5, 6 in Figures 5 and 6. Thus, when the pressurization of the cavity 2 is accompanied by the simultaneous creation of a counter-pressure, advantageously identical to the pressurization pressure of the cavity 2, in the area of ​​the rod 9 which is not immersed in the cavity 2, i.e. in the area of ​​the rod which is on the other side of the closure with respect to the cavity 2, the counter-pressure makes it possible to avoid leaks, at the contact between the docking area and the rim, of the pressurization gas of the cavity.

[0412] To create the counter pressure, before the injection step 107 of the supercritical mixture into the cavity 2 of the mold 1, the method 100 comprises for example a step 103bis of placing a cover 13 on the mold 1 so as to form with the mold 1 a closed volume comprising the cavity 2, and a complementary part 14 of the cavity 2 in said closed volume, the complementary part 14 and the cavity 2 being located on either side of the closure of the cavity 2 at the level of the contact between the docking zone 6 and the rim 5.Figure 6 in particular shows the cover 13 placed on the mold 1, in order to form the closed volume comprising the cavity 2 on the one hand and the complementary volume 14 on the other hand; the surface 7 of the part of the rod 9 intended to be taken in the foamed material of the sole 3 is located inside the cavity 2 of the mold 1, and the surface of the other part of the rod is located inside the complementary part 14 of the cavity 2 in the closed volume formed by the cover 13 placed on the mold 1. In Figure 5 in particular the cover 13 of the mold 1 is shown above the mold which corresponds to it, but the person skilled in the art will understand that the method works just as well with a mold 1 above the cover 13 as is illustrated by way of example in Figure 1 in perspective.As illustrated in Figures 5 and 6, gaskets 15 may also be placed at a contact area between the cover 13 and the mold 1 to ensure proper sealing of the closed volume constituted by the cover 13 and the mold 1.

[0413] The complementary part 14 is pressurized, for example by injecting a gas into said complementary part 14 at a pressure similar to the pressure of the cavity 2 so that the sealing defects at the level of the zone 6 and the rim 5 do not create a leak of a pressurizing gas between the cavity 2 and the complementary part 14, the pressure in the complementary part 14 acting as counter pressure opposing the pressure in the cavity 2. The injection 107 of the supercritical mixture into the cavity 2 can then take place, for example via an injection channel 4 passing through the mold 1, as illustrated in FIG. 6.

[0414] The injection of the pressurizing gas is carried out via one or more pressurizing channels 119, 119bis, distinct from the injection channel(s) 4 of the mixture, as illustrated in FIGS. 32 and 33. In particular, a pressurizing channel 119 can be used for the pressurization of the cavity 2, and a complementary pressurizing channel 119bis can be used for the pressurization of the complementary cavity 14, as illustrated in FIG. 33.

[0415] According to an exemplary implementation, the cover 13 is configured to form with the mold 1 a sealed closed volume, in particular gas-tight, around at least one part of the rod 9, so as to allow the creation of said counter-pressure inside this sealed closed volume, in particular by receiving the pressurizing gas from the cavity 2 in this sealed volume, in order to avoid leaks, at the contact between the docking zone and the rim, of a pressurizing gas from the cavity.

[0416] Advantageously, the area of ​​at least one part of the rod 9 on the other side of the closure relative to the cavity 2 can be depressurized simultaneously with the depressurization of the cavity 2 of the mold 1 to trigger an expansion of the mixture in the cavity 2 and form the sole during the method 100 according to the invention.

[0417] For example, a cavity pressurization pressure is between 3 bars and 50 bars, preferably between 10 bars and 30 bars, preferably equal to 15 bars.

[0418] With reference to figure 19, we describe the complete sequence of the steps of the method 100 for manufacturing a shoe 10, according to an embodiment which therefore comprises the following steps:

[0419] - providing 103 a mold 1 defining an open cavity 2, a shape of at least a part of the cavity 2 corresponding to a shape of a sole 3 of the shoe 10, the cavity 2 being configured to receive, via at least one injection channel 4 opening into the cavity 2, a mixture comprising a molten material and a supercritical fluid;

[0420] - placing 105 a rim 5 of an opening of the cavity 2 open in contact with a docking zone 6 of a surface 7 of at least one part of an upper 9 of the shoe 10, so that the surface 7 of the at least one part of the upper 9 ensures a closure of the cavity at the level of the contact between the docking zone 6 and the rim 5;

[0421] - pressurize 105bis the cavity 2, in particular by injecting a gas into said cavity 2;

[0422] - inject 107 the mixture into cavity 2;

[0423] -depressurizing 108 the cavity 2 of the mold, in particular by evacuating the gas from said cavity 2, to trigger an expansion of the mixture in the cavity 2 and form the sole 3 in a foamed material resulting from the expansion of the mixture, at least one part of the surface 7 of the at least one part 9 of the upper being taken in said foamed material of the sole 3.

[0424] According to these provisions, the method makes it possible to obtain, in a single injection step 107, a light and shock-absorbing sole of the shoe 10 connected to a part of an upper 9 of the shoe 10, with good resistance to detachment of the sole 3 and the upper 9.

[0425] Pressurization in the cavity 2 followed by depressurization in the cavity 2 allows expansion of the mixture and the production of the light and cushioning foamed material of the sole. Pressurization pressure in the complementary part 14 of the closed volume ensures sealing, in particular against gas, of the closure of the cavity 2, at the level of contact between the docking zone 6 and the rim 5.

[0426] The molten material is, for example, a thermoplastic elastomeric polymer.

[0427] According to an example of implementation, the thermoplastic polymer is a thermoplastic polyurethane (TPU), or an ether-amide block copolymer (PEBA), or an ethylene vinyl acetate (EVA), or a polyolefin, or an ether-ester block copolymer, or a styrene-based elastomer, or a mixture of these different components.

[0428] Supercritical fluid is for example nitrogen in a supercritical state or carbon dioxide in a supercritical state or a mixture of nitrogen and carbon dioxide in a supercritical state.

[0429] The density of the sole 3 finally obtained is between 0.1 g / cm3 and 0.4 g / cm3, preferably between 0.15 g / cm3 and 0.25 g / cm3.

[0430] Furthermore, the part of the upper 9 taken in the foamed material of the sole 3 makes it possible to obtain a peel resistance greater than 2.5 N / mm, measured according to the ISO NE EN 1392 standard.

[0431] In particular, step 105bis of pressurizing the cavity 2 may for example comprise the following step:

[0432] - placing 103bis a cover 13 on the mold 1 so as to form with the mold 1 a closed volume comprising the cavity 2, and a complementary part 14 of the cavity 2 in said closed volume, at least one part of the rod 9 being located inside said closed volume, the complementary part 14 and the cavity 2 being located on either side of the closure of the cavity 2 at the level of the contact between the docking zone 6 and the rim 5.

[0433] A pressurization pressure in the complementary part 14 of the closed volume makes it possible to avoid leaks, at the contact between the docking zone 6 and the rim 5, of a pressurization gas from the cavity 2.

[0434] According to an exemplary implementation, illustrated in Figure 3, the part 9 of the rod is placed directly on the rim 5 of the opening of the cavity 2 of the mold 1, without using a support 8 to hold the rod.

[0435] In particular, the method may comprise a complementary step of assembling the part of the upper 9 connected to the sole 3 obtained after the depressurization step, with another part 9' of the upper, the assembly forming the shoe 10, as illustrated in Figure 4. By way of example, the assembly step may comprise sewing the other part 9' of the upper with the part of the upper 9 connected to the sole 3.

[0436] According to another example of implementation, illustrated in Figures 5 and 6, the part 9 of the upper is first placed on a support 8 so as to cover 102 at least in part an external surface of said support 8, said support 8 having a shape corresponding to a shape of a foot; a part of the surface 7 of the part of the upper 9, intended to be taken in the foamed material of the sole 3, covers a part of the external surface of the support 8 corresponding to a sole of said foot.During the step 105 of placing the part of the rod 9 on the rim 5 of the cavity 2, the part of the rod 9 is thus placed, with the support 8, on the rim 5 of the cavity 2, so that after the placement 103bis of the cover 13 on the mold 1, the closed volume further comprises the support 8 with the part of the rod 9; the surface 7 of the part of the rod 9 intended to be taken in the foamed material of the sole 3 is located inside the cavity 2 of the mold 1, with a corresponding part of the support 8, and the surface of the other part of the rod 9, with another corresponding part of the support 8, is located inside the complementary part 14 of the cavity 2 in the closed volume formed by the cover 13 placed on the mold 1.

[0437] The rod 9 may for example be a complete rod, as illustrated for example in Figure 7.

[0438] The support 8 can be made, for example, of aluminum, steel, or plastic.

[0439] Thus, the method 100 makes it possible to obtain, in a single injection step 107, a complete shoe 10 comprising a sole 3 of the shoe connected to a complete upper 9 of the shoe 10, as illustrated in FIG. 8.

[0440] The mold 1 is in one part, or the mold 1 comprises several parts 1 ', 1 ”, 1 ” ', as illustrated in Figure 2, and the step of providing 103 the mold 1 comprises a step of assembling the different parts 1 ', 1 ”, 1 ” to form the mold 1. For example, the multi-part mold 1 ' , 1 ”, 1 ' ” may comprise a mold bottom 1 ” ', and two halves 1 ', 1 ” of a ring part of the mold, as illustrated in Figure 2; said two halves 1', 1” are configured to form a ring when assembled, said ring being configured to form the rim 5 of the cavity 2 when it is placed on the bottom 1'” of the mold 1, said rim 5 then being configured to receive the docking zone 6 of the part of the rod 9.Furthermore, as illustrated in Figures 5 and 6, one or more gaskets 15' may also be placed at a contact area between the different parts 1', 1”, 1'” of the mold to ensure proper sealing of the mold 1.

[0441] According to an exemplary embodiment of the mold, illustrated in Figures 28 to 31, the mold comprises a mold base 1'” and two halves 1', 1” of a ring portion of the mold, similarly to the mold of Figure 2; note that in Figure 28, the mold base 1'” is above the two halves 1' and 1” of the ring portion, whereas in Figure 2, the mold base is below; those skilled in the art will understand that this difference in representation is not significant. As in Figure 2, said two halves 1' and 1” of the ring portion are configured to form a ring when assembled, said ring being configured to form the rim 5 of the cavity 2 when it is placed on the mold base 1'”, said rim 5 then being configured to receive the docking zone 6 of the portion of the rod 9.

[0442] According to the particular embodiment of figure 28, said mold base 1'” comprises two distinct parts, on the one hand a cover 115, on the other hand a bell 114, said bell 114 being configured to envelop all of the parts comprising the cover 115 and the two halves 1', 1” of the ring part, when the mold is closed;More particularly, the two halves 1', 1” of the ring portion of the mold are configured to be mechanically actuated so as to be moved relative to each other, by sliding in a sliding direction, a first half 1' moving in a direction D' of the sliding direction, and the second half 1” moving in an opposite direction D” of the sliding direction, so that the two halves 1', 1” of the ring move away from each other as illustrated in Figures 30c or 31c, or move towards each other as illustrated in Figures 30a or 31a, depending on whether the sliding movement of the two halves is in a first direction, illustrated in Figures 30c or 31c, or in a second direction, illustrated in Figures 30a or 31a;thus the mold ring closes when the two halves 1', 1” are actuated to move towards each other, and conversely the mold ring opens when the two halves 1', 1” are actuated to move away from each other.;

[0443] More particularly still, a contact interface between the bell 114 of the mold bottom 1'” and each of the two halves 1', 1” of the ring is configured so that the sliding movement of the two halves in the direction of separation of the two halves 1', 1” of the ring actuates a movement of the bell 114 of the mold bottom 1'” in a direction D'” transverse to the sliding direction, so that the bell 114, initially in contact with the closed ring formed by its two halves 1', 1” brought together, moves away from the ring when its two halves 1', 1” move away from each other.Conversely, when the bell 114 of the mold base 1'” is pushed to approach, in the direction D” ' transverse to the sliding direction, the two halves 1', 1" of the ring, the pressure P exerted by the bell 114 on the two halves 1', 1" at the contact interface, as illustrated in Figures 30b and 31b, actuates a sliding movement of the two halves 1', 1" so as to close the ring. An elastic member 118 may be provided so that the two halves 1', 1" of the ring move away from each other when the bell 114 of the mold base 1'” is moved away from the ring in the direction D'” transverse to the sliding direction.

[0444] For this purpose, as illustrated in Figures 28 to 30, the contact interface between the bell 114 of the mold bottom 1'” and each of the two halves 1', 1” of the ring, comprises a first contact plane 114' between the bell 114 of the mold bottom 1'” and the first half 1' of the ring, said first contact plane 114' being inclined relative to the sliding direction at a first angle, and a second contact plane 114” between the bell 114 of the mold bottom 1'” and the second half 1” of the ring, said second contact plane 114” being inclined relative to the sliding direction at a second angle, the second angle being of opposite sign to the first angle.Said first contact plane 114' is configured to slide in contact with a corresponding first contact surface 116' of a wall of the first half 1' of the ring, and said second contact plane 114” is configured to slide in contact with a corresponding second contact surface 116' of a wall of the second half 1” of the ring.

[0445] According to a variant of the exemplary embodiment illustrated in figures 28 to 30, said variant being illustrated in figure 31, the contact interface between the bell 114 of the mold bottom 1'” and each of the two halves 1', 1” of the ring, comprises at least one guide 117', 117” configured to accompany the sliding movement of the two parts 1' and 1” of the ring when the bell 114 of the mold bottom 1'” moves in the direction transverse to the sliding direction.

[0446] According to these arrangements, the mold can be actuated alternately, to be closed, by a displacement of the mold bottom 1 ' ” in the direction D” ' transverse to the sliding direction, and to be opened, by a sliding displacement of the two halves 1 ', 1 ” so as to open the ring. The displacement of the mold bottom 1'” for closing can be obtained, for example, by a pressure exerted on the mold bottom 1”' towards the ring; sliding displacement of the two halves 1', 1 ” for opening can be obtained, for example, by an elastic device.

[0447] To enable the implementation of the injection step 107, the cavity 2 of the mold is configured to receive, via at least one injection channel 4, 4', 4”, 4”' opening into the cavity 2, the mixture comprising a molten material and a supercritical fluid.

[0448] For example, the mold may comprise an injection channel 4 opening into the cavity 2, as illustrated in FIG. 6. According to another example, the injection channel 4 opening into the cavity 2 may pass through the support 8 of the rod 9, as illustrated in FIG. 15.

[0449] According to yet another example, the cavity 2 is configured to receive the mixture via at least two injection channels 4', 4”, 4'” opening into the cavity 2, as illustrated in Figure 14 in which are shown, by way of example, 3 injection channels 4', 4”, 4'”. Thus, the method 100 makes it possible to obtain more quickly, and with a more homogeneous filling of the mold cavity, a sole 3 of the shoe 10 connected to a part of the upper 9 of the shoe 10.

[0450] To improve the strength of the connection between the upper 9 and the sole 3, it is in particular possible to provide an additional step of gluing 106 of the part of the surface 7 of the part of the upper 9, the gluing step 106 being carried out before the injection step 107. Alternatively, or in combination with the gluing step 106, the part of the surface 7 of the part of the upper 9 may comprise hot-melt threads configured to melt at an injection temperature of the mixture. Thus, the resistance to detachment of the sole and the upper is reinforced.

[0451] According to an example of implementation of the method, the part of the surface 7 of the part of the upper 9, intended to be taken in the foamed material of the sole 3, is solid as illustrated in Figure 11. To reinforce the resistance to detachment, it is also possible to provide that the part of the surface 7 of the part of the upper 9, intended to be taken in the foamed material of the sole 3, is perforated, i.e. the part of the surface 7 comprises holes as illustrated in Figure 12 or in Figure 3 with, for example, 3 holes passing through the part of the surface 7 of the part of the upper 9; it is also possible to provide that the part of the surface 7 is at least partly open as illustrated in Figure 10 with, for example, said part of the surface 7 almost completely open except for a part of this surface 7 near the docking zone 6.In the case shown in Figure 3, in which 3 holes pass through the part of the surface 7 of the part of the rod 9, and in which the part of the rod 9 intended to be taken in the foamed material of the sole 3 is not placed on a support 8, the cover 13 must ensure the closing of the holes or openings of the part of the surface 7 of the part of the rod 9 during the steps 105bis of pressurizing the cavity 2 and of injecting 107 the mixture into the cavity. For this purpose, the cover 13 may for example, as illustrated in Figure 3, rest, for example with a substantially flat and plane inner surface, on said part of the surface 7 of the part of the rod 9 so as to close the holes or openings present on this part of the surface 7 of the part of the rod 9.

[0452] Yet another way of reinforcing the resistance to detachment consists in providing that the part of the surface 7 of the part of the upper 9, intended to be taken in the foamed material of the sole 3, is textured or perforated in contact with or near the docking zone 6, as illustrated in figure 13.

[0453] In order to improve the abrasion resistance of the sole 3, or the rigidity of the sole 3, the method 100 may comprise the complementary steps of providing 104 and positioning 104bis one or more inserts 12, 12', 12” configured to be positioned in the cavity 2 of the mold 1.

[0454] For example, the insert(s) 12, 12' shown in Figure 16 are positioned to be inserted at an external surface of the sole, as illustrated respectively before and after the step 107 of injecting the mixture into the cavity 2 in Figures 17 and 18; according to another example, one or more inserts 12” may be positioned to be embedded inside the sole 3, as illustrated respectively before and after the step 107 of injecting the mixture into the cavity 2 in Figures 17 and 18.

[0455] According to these provisions, the abrasion resistance of the sole is reinforced, or a rigidity of the sole is improved, depending on whether respectively the inserts 12, 12' are inserted towards an external portion of the sole 3, for example with inserts 12, 12' made of rubber or thermoplastic material, or whether the insert is or the inserts 12” are embedded inside the sole 3, for example with inserts 12” made of carbon plate or thermoplastic material.

[0456] According to one embodiment, an insert 12” positioned to fit at an external surface of the sole 3 comprises one or more through holes 120, the one or more through holes 120 being matched with one or more pressurization channels 119, as illustrated in Figure 34, so that a pressurization gas can pass through the insert.

[0457] According to an exemplary implementation, a contact surface 112 between the insert and the sole has a particular geometry, in order to reinforce, by mechanical attachment, the adhesion between the insert and the sole, while avoiding the steps of gluing or surface preparation. For example, the particular geometry of the insert includes a texture of the contact surface, as illustrated in figures 25, 26 or 27.

[0458] The texture comprises for example a plurality of patterns formed on the contact surface 112, the plurality of patterns being distributed over the surface, according to a determined density, so that on a portion of the contact surface the plurality of patterns occupies a part of the portion of the contact surface, said part being between 1% and 15%, advantageously 6%, of the portion of the contact surface. The patterns are preferably distributed homogeneously over the contact surface, according to the determined density. The distribution of the patterns can also be densified in certain areas of the contact surface for which the stresses are greater. In other words, the distribution density of the patterns on an area of ​​the contact surface can be a function of the stresses to which the area in question is subjected.

[0459] The patterns have a height, measured along a direction of the height transverse to the contact surface, said height being between 1 mm and 10 mm, preferably equal to 1.6 mm.

[0460] The patterns have a thickness, measured in a direction transverse to the height direction; said thickness being between 1 mm and 2 mm, preferably equal to 1.6 mm. Said thickness is a diameter, respectively a width, depending on whether the patterns are tubular or cylindrical as illustrated in Figure 25, respectively linear as illustrated in Figure 26.

[0461] The texture may include tubular or cylindrical patterns in the center of the contact surface and a linear pattern around a periphery 113 of the contact surface, as illustrated in Figure 27, to prevent the onset of detachment.

[0462] The linear pattern on the periphery may be a burr obtained on a parting plane of a closure of an overmolding mold of the insert, which makes it possible to avoid removing said burr.

[0463] According to one aspect, the invention also relates to an article of footwear, for example a shoe 10 obtained by the method 100 according to one of the embodiments previously described.

[0464] According to another aspect, the invention also relates to a device comprising a mold 1, and optionally a cover 13, and optionally a support s, configured to implement the method 100 according to one of the embodiments previously described.

[0465] According to one embodiment, the device comprises a mold 1 defining an open cavity 2, a shape of at least a portion of the cavity 2 corresponding to a shape of a sole 3 of the shoe 10, the cavity 2 being configured to receive, via at least one injection channel 4, 4', 4”, 4'” opening into the cavity 2, a mixture comprising a molten material and a supercritical fluid, a rim 5 of an opening of the open cavity 2 being configured to be placed in contact with a docking zone 6 of a surface 7 of at least a portion of an upper 9 of the shoe 10, so that the surface 7 of the at least a portion of the upper 9 ensures a closure of the cavity at the contact between the docking zone 6 and the rim 5, so that said device is thus configured to implement the manufacturing method 100 according to one of the exemplary implementations described above.

[0466] According to a complementary exemplary embodiment, the device further comprises a cover 13 configured to be placed on the mold 1 so as to form with the mold a closed volume comprising the cavity 2, and a complementary part 14 of the cavity in said closed volume, the at least one part of the upper 9 of the shoe being located inside said closed volume, the complementary part 14 and the cavity 2 being located on either side of the closure of the cavity 2 at the level of the contact between the docking zone 6 and the rim 5, the device thus being configured to implement the manufacturing method 100, according to one of the implementation modes described above.

[0467] According to another complementary exemplary embodiment, the device further comprises a support 8 having a shape corresponding to a shape of a foot, an external surface of the support 8 being configured to be covered with at least one part of the upper 9 of the shoe, the at least one part of the surface 7 of the at least one part of the upper 9 covering a part of the external surface of the support corresponding to a sole of said foot.

[0468] According to an exemplary embodiment, the shoe 10 shown in Figure 20 comprises a sole obtained by the method 100 described above; a majority by mass of the sole is made of a main sole material; in other words the foamed material, resulting from the expansion of the mixture implemented in the method 100, comprises said main sole material; the shoe 10 further comprises an upper 30 of which a majority by mass is made of a main upper material.

[0469] The main sole material may be selected from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPUs), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester.

[0470] The main sole material is, for example, a styrenic thermoplastic elastomer, in particular chosen from SEBS (possibly grafted), SBS, SBC, SIS, and SEPS, in this specific example SEBS.

[0471] The main sole material is advantageously chosen from polyesters, thermoplastic polyurethanes (TPU), polyolefins, and block copolymers composed of rigid polyamide blocks and flexible polyether blocks (and in particular the compound marketed under the name Pebax® by the company Arkema).

[0472] The sole 20 may comprise a first auxiliary sole material, in particular a polyolefin, more particularly it is polypropylene, the foamed material, resulting from the expansion of the mixture, comprising said main sole material and the first auxiliary sole material.

[0473] The main upper material may be selected from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPUs), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester; and for example a polyolefin, in particular polyethylene or polypropylene, in this specific example polypropylene.

[0474] The main upper material is advantageously chosen from polyesters, thermoplastic polyurethanes (TPU), polyolefins, and block copolymers composed of rigid polyamide blocks and flexible polyether blocks (and in particular the compound marketed under the name Pebax® by the company Arkema).

[0475] Advantageously, the rod 30 comprises a lace 35 made of polypropylene, in particular comprising braided polypropylene threads.

[0476] Advantageously, the rod 30 comprises a component 40 folded back on itself and comprising a foam laminated on its two faces with a textile notably chosen from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester. The textiles are preferably made of polypropylene and / or polyethylene, in particular a fabric or a knit with polypropylene yarns and / or polyethylene yarns, preferably polypropylene yarns.The foam may be selected from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, thermoplastic polyurethanes (TPUs), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester; for example, a polyethylene foam.

[0477] The upper 30 may also comprise a foam component 50 housed in the fold of the external component 40, preferably made of polyethylene, said foam improves the reception of the rearfoot. The foam may be chosen from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester.

[0478] The edges of the component 40 folded back on itself can be secured using any technique known to those skilled in the art, for example using one or more seams, preferably made with one or more threads made of a material chosen from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester, in particular one or more polyolefin threads, in particular polypropylene.

[0479] Preferably, the upper component 40 is arranged in the rearfoot region 12a and partly in the medial 18 and lateral 16 foot regions. Advantageously, the upper 30 further comprises the upper component 42 arranged in the forefoot regions 14a, and partly in the lateral 16 and medial 18 foot regions. The upper component 42 may comprise a knit or a fabric. The upper 30 may comprise other upper component(s). The set of upper components including the components 40 and 42 are preferably shaped in three dimensions using a mounting insole.Preferably, the insole comprises a material selected from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester; for example, a polyolefin nonwoven, in particular polypropylene. The insole is advantageously heat-melted along all or part of its surface to improve its tear resistance. The upper 30 comprises, as well as preferably any upper according to the invention, a rearfoot region 12a, a forefoot region 14a, a lateral region 16, a medial region 18 and an instep region 19 comprising a tongue.

[0480] The shaping of the component 40, with possibly other upper component(s), on a foot-shaped preform (called lasting operation) is carried out for example using a cord comprising a material chosen from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester; and in particular a polypropylene cord (for example a circular braid not shown) tensioning the lower edges of the textile component 40 and possibly of the other upper component(s).

[0481] The shoe 10 may also include lacing eyelets 55 in the molded main upper material, for example, polypropylene lacing eyelets 55.

[0482] The shoe 10 may also comprise a non-woven fabric made of polypropylene or polyethylene coated in whole or in part with a poly(ethylene-vinyl acetate) (EVA) coating making it possible to secure by gluing, when the EVA is activated by heating, the lacing eyelets 55 to the external textile component 50.

[0483] The shoe 10 may comprise textile strips 60 and 61, in particular woven, made of polyethylene and / or polypropylene, in particular comprising polypropylene threads and / or polyethylene threads, in particular polypropylene threads. Each textile strip 60 and 61 comprises a lacing zone 62 forming a sheath for the passage of a lace.

[0484] The textile strips 60 and 61 preferably each have a width 11 and 12 greater than or equal to 5 mm, in particular greater than or equal to 10 mm, more particularly greater than or equal to 15 mm. Preferably, the textile strip 60 comprises a first end 64 and a second end 66 secured to the component 40. The first and second ends 64, 66 are spaced from each other so that the textile strip 60 forms an inverted V.

[0485] Preferably, the textile strip 61 comprises a first end 65 and a second end 67, substantially superimposed, and secured to the component 40.

[0486] Preferably, the lacing zone 62 comprises a portion of the textile strip 60 or 61 folded back on itself and thus forming a sheath for the passage of a lace.

[0487] Textile strips 60 and 61 also form lateral reinforcement zones.

[0488] The upper 30 may comprise a rear counter 70 secured in the rear foot region 14 of the component 40. This rear counter 70 is preferably a molded part made of polypropylene.

[0489] The rod 30 may also comprise a front hard tip 90 in a molded material, for example in the main rod material, preferably in a polyolefin, an olefinic thermoplastic elastomer, or even a vulcanized thermoplastic elastomer, or a styrenic thermoplastic elastomer, such as SEBS.

[0490] For this specific embodiment, the main rod material of the rod 30 is a polyolefin, in particular polypropylene. This is in fact the basic thermoplastic material whose mass fraction is the majority, that is to say the largest compared to the mass fractions of the other materials.

[0491] The rod 30 also comprises a first auxiliary rod material, different from the main rod material, which in this specific example is polyethylene.

[0492] In this specific example, the mass fraction of polyolefin in the rod is of the order of 55.17%, in particular the mass fraction of polypropylene (main rod material) in the rod is of the order of 44.83%, and the mass fraction of polyethylene (first auxiliary rod material) is of the order of 10.34%. The mass fraction of thermoplastic olefinic elastomer (TPO) in the rod is of the order of 27.59% (second auxiliary rod material), and finally the mass fraction of glue is of the order of 17.24%.

[0493] The ratio of the mass of the main upper material 30, in this specific example polypropylene, and the mass of the auxiliary upper materials 30, for example PE and TPO, relative to the total mass of the upper 30, is greater than or equal to 80%, in particular of the order of 82% or more if the glue used is EVA. This ratio preferably tends towards 100%. When the materials are recycled, there may remain one or more contaminating material(s) whose mass fraction nevertheless remains low, for example of the order of 5% or less.

[0494] It is possible for the sole 20 to be manufactured at the same time as it is secured to the upper. In this case, the sole is injected directly onto the upper, i.e. onto the lower part of the upper 30. Advantageously, the main material of the upper 30 is compatible with, or in the same basic thermoplastic material as, the main sole material, so that the sole adheres to the upper, preferably without using an external bonding agent.

[0495] Preferably, the mass fraction of the main sole material, in particular SEBS, in the sole is of the order of 65%. The mass fraction of polyolefin, in particular polypropylene mixed with SEBS, in the sole is of the order of 20%. The mass fraction of filler (for example calcium carbonate) in the sole is of the order of 5%. Finally, the mass fraction of plasticizer in the sole is of the order of 10%.

[0496] The shoe 10 essentially comprises a material chosen from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethane (TPU), an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester; and in particular polypropylene, polyethylene, a TPO and SEBS, SEBS being predominant in the sole and polypropylene being predominant in the upper. Recycling of the shoe is thus facilitated since it is not necessary to separate the different components. The shoe is ground and then the ground materials are transformed into thermoplastic granules capable of being transformed by a conventional thermoplastic shaping technique.The thermoplastic granules therefore comprise a thermoplastic mixture comprising the materials selected in the present invention which are compatible with each other during their hot transformation, and exhibit good adhesion to each other.

[0497] Thermoplastic granules can thus advantageously be extruded and injected to manufacture all or part of a wear sole or a midsole.

[0498] Thermoplastic granules can also be processed to make a hard front toe or a rear counter or even lacing eyelets, a foam component or agglomerated or non-agglomerated foam beads.

[0499] Figure 22 represents a second example cited without limitation of a shoe 200 according to the invention, comprising a sole 220 and an upper 230. The main upper material can be chosen from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethanes (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester; preferably in this specific example a polyolefin, in particular polypropylene.

[0500] The upper 230 comprises a textile part 240 forming a foot receiving zone having an external face 245, and four strips 250, 251, 252 in an olefinic thermoplastic elastomer secured to the external face 245 and to said sole 220. A part of each of the strips is arranged between the sole 220 and the external face 245 of the textile part 240.

[0501] A strip 250 is disposed along the front edge 205 of the shoe 200, and extends from a lateral side to a medial side of the shoe 200. A strip 251 is disposed along the rear edge 206 of the shoe 200, and extends from a lateral side to a medial side of the shoe 200. A strip 252 is disposed partially along the medial side 207 of the shoe 200, and extends between the front strip 250 and the rear strip 251. A strip, not visible in the photograph of FIG. 4, is disposed partially along the medial side of the shoe 200, and extends between the front strip 250 and the rear strip 251.

[0502] Advantageously, the textile portion 240 forming a foot receiving area comprises a textile component which comprises a yarn comprising the main upper material, in particular the main upper material is a polyolefin or an olefinic thermoplastic elastomer.

[0503] Preferably, the four strips, including strips 250-252, are leatherette type strips.

[0504] Advantageously, each strip comprises a polymer layer based on an olefinic thermoplastic elastomer, said polymer layer being arranged on a textile substrate. Said strips are thus advantageously compatible with the polymer material(s) of the textile part 240 and of the sole 220 so that they can be bonded by at least partial fusion of their structures to the textile part 240 and to the sole 220. Said strips, the strips 250-252 of which are bonded to the external face 245 of the textile part 240 so that the textile substrates are oriented opposite the external face 245.

[0505] The strip, such as one of the strips 250 to 252, may have a configuration different from that of a strip depending on the functions to be performed on the shoe. Generally, said strip may be a piece of imitation leather type having a shape determined according to its final function. In this specific example, the external faces of the strips 250 to 252 are substantially smooth, but they may include one or more relief pattern(s) imparted to the polymer layer, for example by calendering.

[0506] Figure 23 shows a third example cited without limitation of a shoe 80 according to the invention. The shoe 80 comprises a sole comprising a midsole 21 and an outsole 22, the majority by mass of the sole being made of a main sole material, and an upper 36 of which a majority by mass is made of a main upper material.

[0507] The main sole material is polyester.

[0508] The main material of the midsole 21 may be a thermoplastic copolyester of the TPEE (thermoplastic polyether ester elastomer) or TPC-ET (Thermoplastic copolyester elastomers) type. These are block copolymers comprising rigid polyester segments and soft polyether and / or polyester segments. The main material of the midsole 21 may be a thermoplastic copolyester, called COPE (Copolyester thermoplastic elastomer) or TPC (Thermoplastic Copolyester), of the TPC-EE (TPC with soft segments with both ether and ester linkages), TPC-ES (TPC with soft segments with ester linkages) or TPC-ET (TPC with soft segments with ether linkages).

[0509] The midsole 21 may be obtained by injection of supercritical fluid, as described previously.

[0510] The midsole 21 is advantageously co-molded with the outsole 22. The outsole 22 may also be bonded with the midsole 21.

[0511] The midsole 21, with or without the outsole 22, can be injected onto the upper. Alternatively, the sole and the upper 36 can be produced separately and assembled later.

[0512] The main material of the outsole 22 may be chosen from thermoplastic elastomers of the TPV type.

[0513] Thermoplastic vulcanizates (TPV) fall into the class of thermoplastic elastomers and possess, to a certain extent, the characteristics of both thermoplastics and elastomers. Generally, they are systems consisting of two phases, one soft, the elastic phase (EPDM) and the other hard, the thermoplastic phase (PP).

[0514] Preferably, a thermoplastic vulcanizate is used comprising a thermoplastic phase made of thermoplastic copolyester, and in particular TPEE. The soft phase may be poly(styrene / butadiene), also called SBR rubber (for styrene - butadiene rubber in English), which is a copolymer of styrene and 1,3-butadiene. The thermoplastic phase may be a thermoplastic phase made of block copolymer comprising rigid polyester segments and soft polyether and / or polyester segments.

[0515] Alternatively, the outsole 22 may comprise rubber. In this case, the outsole 22 is advantageously fixed to the midsole 21 using a specific bonding primer which allows the outsole 22 to be disassembled for the purpose of recycling the shoe.

[0516] The shoe 80 may also include a TPEE or TPC-ET insole, which may be obtained by foaming by injection of supercritical fluid, as described previously.

[0517] The main upper material is also preferably a polyester.

[0518] Advantageously, the upper 36 comprises a lace 23 made of polyethylene terephthalate (PET). The shoe 80 may comprise lacing eyelets 24 made of polyethylene terephthalate (PET).

[0519] The rod 36 may comprise a lower part 25 which is a protective layer bonded to the rod. The lower layer 25 is advantageously made of thermoplastic copolyester, and in particular of the TPEE or TPC-ET type.

[0520] The rod 36 may also comprise an upper portion 26 comprising polyethylene terephthalate (PET) and / or a thermoplastic copolyester, for example TPEE.

[0521] Figure 21 shows an exemplary embodiment of the upper part 26. The upper part 26 may comprise an upper layer 26a of PET, for example a two-dimensional woven PET mesh, and a lower layer 26b also of PET, for example a three-dimensional woven PET mesh. A central layer 26c of thermoplastic copolymer, for example TPEE, and in particular non-woven TPEE, is surrounded upwards and downwards by an intermediate layer of adhesive 26d, 26e. An upper intermediate layer 26d is disposed between the central layer 26c and the upper layer 26a, while a lower intermediate layer 26e is disposed between the central layer 26c and the lower layer 26b.

[0522] At the rear of the shoe 80, between the upper 36 and the midsole 21, a reinforcing ring 27 is arranged, which is a rigid injected insert, the insert being positioned in the mold, and assembled or not with the upper. The ring 27 is advantageously made of thermoplastic copolyester, and in particular of the TPEE or TPC-ET type. The ring 27 can be glued between the upper 30 and the midsole 21.

[0523] The upper 36 may also include an upper reinforcement 51 made of foam improving the support of the rearfoot. The upper reinforcement 51 may be made of PET, and in particular of non-woven PET.

[0524] The upper 36 includes a rearfoot region 28, a forefoot region 29, a lateral region 31, a medial region 32 and an instep region 33 including a tongue 34.

[0525] The tab 34 is advantageously made of PET, and in particular of non-woven PET.

[0526] The upper may include a polyester thread, particularly TPEE, which gives the shoe flexibility.

[0527] The outsole 22 is preferably manufactured at the same time as it is secured to the upper. In this case, the outsole is injected directly onto the upper, i.e. onto the lower part of the upper 36, preferably using the method described above.

[0528] Advantageously, the main material of the upper 36 is compatible with, or in the same base thermoplastic material as, the main sole material, so that the outsole adheres to the upper, preferably without using an external bonding agent.

[0529] Alternatively, it is possible for the shoe 80 to be manufactured using a conventional Strobel-type assembly. The outsole 22 can be secured to the upper 36 by gluing. The outsole 22 and the upper 36 are therefore manufactured separately and then secured.

[0530] The adhesives that can be used to assemble the different parts of the shoe 80, and in particular to assemble the upper to the sole, can be polyurethane or polyester-based adhesives.

[0531] The table below summarizes mechanical properties measured on examples of polymer blends from the recycling of shoes obtained by the process according to the invention.

[0532] The mixture in Example 1 is derived from the recycling of a shoe that does not contain any contaminating material within the meaning of this text. The shoe recycled to obtain the mixture in Example 1 thus comprises 50g of polypropylene (PP), 12g of polyethylene (PE), 250g of styrene-ethylene-butadiene-styrene (SEBS), and 25g of a vulcanized thermoplastic elastomer (TPV, in this specific example EPDM (ethylene-propylene-diene) / PP (polypropylene)).

[0533] The recycled shoe for obtaining the mixture of Example 2 is identical to the shoe of Example 1 except that the sole of the recycled shoe in this Example 2 comprises thermoplastic polyurethane whose mass fraction is 2%. The recycled shoe of the mixture of Example 3 is identical to the shoe of Example 2 except that the mass fraction of thermoplastic polyurethane in the shoe is 5%.

[0534] The recycled shoe from the mixture of Example 4 is identical to the shoe from Example 2 except that the mass fraction of thermoplastic polyurethane in the shoe is 10%.

[0535] The shoe of the blend of Example 5 is identical to the shoe of Example 1 except that the shoe of Example 5 comprises 2% by mass of thermoplastic polyamide from a polyamide hook and loop fastening system of the recycled shoe.

[0536] It is noted that the presence of polyurethane and polyamide, at most 10% by mass of the shoe, improves the resistance to rupture, but also surprisingly the resistance to abrasion. Beyond 10% by mass of polyurethane, a decrease in abrasion resistance is observed.

[0537] Furthermore, the recycled mixtures obtained are perfectly heat-transformable (extrusion-injection or blowing, or even by hot pressing, extrusion molding, etc.) while maintaining final properties allowing them numerous new applications.

Claims

CLAIMS Method (100) of manufacturing at least a part of an article of footwear (10) comprising the following steps: - providing (103) a mold (1) defining an open cavity (2), a shape of at least a portion of the cavity (2) corresponding to a shape of a sole (3) of the footwear article (10), the cavity (2) being configured to receive, via at least one injection channel (4, 4', 4”, 4”') opening into the cavity (2), a mixture comprising a molten material and a supercritical fluid; - placing (105) a rim (5) of an opening of the cavity (2) open in contact with a docking zone (6) of a surface (7) of at least one part of an upper (9) of the footwear article (10), so that the surface (7) of the at least one part of the upper (9) ensures a closure of the cavity at the level of the contact between the docking zone (6) and the rim (5); - pressurize (105bis) the cavity (2); - inject (107) the mixture into the cavity (2); - depressurizing (108) the cavity (2) of the mold, to trigger an expansion of the mixture in the cavity (2) and form the sole (3) in a foamed material resulting from the expansion of the mixture, at least one part of the surface (7) of the at least one part (9) of the upper being taken in said foamed material of the sole (3). Method (100) according to claim 1, further comprising, prior to the step of pressurizing (105bis) the cavity (2), the following step: - placing (103bis) a cover (13) on the mold (1) so as to form with the mold (1) a closed volume comprising the cavity (2), and a complementary part (14) of the cavity (2) in said closed volume, the at least one part of the rod (9) being located inside said closed volume, the complementary part (14) and the cavity (2) being located on either side of the closure of the cavity (2) at the level of the contact between the docking zone (6) and the rim (5). Method (100) according to claim 2, further comprising the following steps, implemented before the step of placing (105) the rim (5) of the opening of the cavity (2) open in contact with the docking zone (6) of a surface (7) of the at least one part of a rod (9): - providing (101) a support (8) having a shape corresponding to a shape of a foot, - covering (102), at least in part, an external surface of the support (8) with the at least one part of the upper (9) of the footwear article (10), the at least one part of the surface (7) of the at least one part of the upper (9) covering a part of the external surface of the support (8) corresponding to a sole of said foot, so that after the placement (103bis) of the cover (13) on the mold (1), the closed volume further comprises the support (8) with the at least one part of the upper (9). Method (100) according to one of claims 1 to 3, wherein the cavity (2) is configured to receive the mixture via at least two injection channels (4', 4”, 4'”) opening into the cavity (2). Method (100) according to one of claims 1 to 4, wherein the mold (1) comprises the at least one injection channel (4). Method (100) according to one of claims 3 to 5, wherein the support (8) comprises the at least one injection channel (4). Method (100) according to one of claims 1 to 6, comprising a step of gluing (106) the at least one part of the surface (7) of the at least one part of the rod (9), the gluing step (106) being carried out before the injection step (107). Method (100) according to one of claims 1 to 7, wherein the at least one part of the surface (7) of the at least one part of the rod (9) comprises thermofusible wires configured to melt at an injection temperature of the mixture. Method (100) according to one of claims 1 to 8, further comprising the following steps: - providing (104) inserts (12, 12') configured to be positioned in the mold cavity; - positioning (104bis) the inserts (12, 12') in the cavity (2) of the mold. Method (100) according to one of claims 1 to 9, in which at least one part of the surface (7) of the at least one part of the rod (9) is at least partly perforated or open. Method (100) according to one of claims 1 to 10, in which at least one part of the surface (7) of the at least one part of the rod (9) is textured or perforated in contact with the docking zone (6). Method (100) according to one of claims 1 to 11, in which the molten material is an elastomeric thermoplastic polymer. Method (100) according to one of claims 1 to 12, wherein the supercritical fluid is nitrogen in a supercritical state or carbon dioxide in a supercritical state or a mixture of nitrogen and carbon dioxide in a supercritical state. Method (100) according to one of claims 1 to 13, characterized in that: - a majority by mass of the rod (9, 30, 36, 230) being made of a main rod material, and optionally one or more auxiliary rod material(s); - a majority by mass of the sole (3, 20, 21, 22, 220) being made of a main sole material, and optionally one or more auxiliary sole material(s), the foamed material, resulting from the expansion of the mixture, comprising said main sole material and said auxiliary sole material(s); - the main rod material, and optionally the auxiliary rod material(s), is / are selected from the following materials: polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, a polyurethane thermoplastic (TPU), polyamides, an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester, and - the main sole material, and optionally the auxiliary sole material(s), is / are of the same chemical family as the main upper material, and optionally is / are of the same chemical family as the auxiliary upper material(s), or in that the main sole material, and optionally the auxiliary sole material(s) is / are chemically compatible with the main upper material, and optionally with the auxiliary upper material(s). Method according to claim 14, characterized in that the main sole material, and optionally the auxiliary sole material(s) is / are identical to the main upper material, and optionally is / are identical to the auxiliary upper material(s).Method according to claim 14 or 15, characterized in that the main upper material is chosen from polyesters, thermoplastic polyurethanes (TPU), polyolefins, and block copolymers composed of rigid polyamide blocks and flexible polyether blocks. Method according to one of claims 14 to 16, characterized in that the main sole material is chosen from polyesters, thermoplastic polyurethanes (TPU), polyolefins, and block copolymers composed of rigid polyamide blocks and flexible polyether blocks.Method according to one of claims 14 to 17, characterized in that the upper comprises a yarn comprising a material chosen from: polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethane (TPU), an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester. Method according to one of claims 14 to 18, characterized in that the upper comprises a textile component, and in that the textile component comprises a yarn comprising the main upper material.Method according to one of claims 14 to 19, characterized in that the upper comprises a textile part forming a foot receiving area having an external face, and at least one part, in particular a strip (250,251,252), comprising an olefinic thermoplastic elastomer, said strip (250,251,252) being secured to said external face of the textile part and to said sole. Method (100) according to one of claims 14 to 20, characterized in that the upper comprises a textile part forming a foot receiving area having an external face, and at least one part, in particular a strip (250,251,252), comprising. an olefinic thermoplastic elastomer, said strip (250,251,252) being secured to said external face of the textile part and to said sole. Method (100) according to one of claims 14 to 21, characterized in that the sole comprises a cellular component, and / or foam beads, comprising a material selected from: polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, thermoplastic polyurethane (TPU), an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester. Method (100) according to one of claims 14 to 22, characterized in that the upper (30) comprises a front hard end (90) comprising the main upper material or an auxiliary upper material, and / or a rear buttress (70) comprising the main upper material or an auxiliary upper material.Method (100) according to one of claims 14 to 23, characterized in that the upper (30) comprises at least one eyelet for passing at least one lacing element, said at least one passing eyelet comprises a textile strip comprising at least one thread comprising the main upper material, in particular the main upper material is a polyolefin. Method (100) according to one of claims 14 to 24, characterized in that the upper (30) comprises a foam component comprising the main upper material, in particular the main upper material is a polyolefin. Method (100) according to one of claims 14 to 25, characterized in that the upper (30;130) and / or the sole (20;120), each comprises / comprises, a recycled material from a sole and / or the upper of another shoe, and / or a recycled material from a sole and / or the upper of a boot.Method (100) according to one of claims 14 to 26, characterized in that the ratio of the mass of the main upper material, and possibly of the mass of the auxiliary upper material(s), to the total mass of the upper is greater than or equal to 40%. Method (100) according to one of claims 14 to 27, characterized in that the ratio of the mass of said main upper material and of the mass of the auxiliary upper material(s), to the total mass of the upper is greater than or equal to 50%. Method (100) according to one of claims 14 to 28, characterized in that the ratio of the mass of the main sole material, and possibly of the mass of the auxiliary sole material(s), to the total mass of the sole is greater than or equal to 40%. Method (100) according to one of claims 14 to 29, characterized in that the ratio of the mass of said main sole material and the mass of the auxiliary sole material(s), to the total mass of the sole is greater than or equal to 50%. Method (100) according to one of claims 14 to 30, characterized in that the footwear article (10) comprises at most 10% by mass of one or more contaminating material(s) not chosen from polyolefins, styrenic thermoplastic elastomers, olefinic thermoplastic elastomers, vulcanized thermoplastic elastomers, thermoplastic polyurethane (TPU), an ether-amide block copolymer (PEBA), an ethylene vinyl acetate (EVA), an ether-ester block copolymer, a styrene-based elastomer, and a polyester, in particular at most 10% by mass of one or more thermoplastic contaminating material(s) and / or at most 5% by mass of one or more thermosetting contaminating material(s).Method (100) according to one of claims 14 to 31, characterized in that the main sole material, and possibly the auxiliary sole material(s), is / are derived at least in part from the recycling of at least one other item of footwear (10). Method (100) according to one of claims 14 to 32, characterized in that it further comprises the collection of the item of footwear (10), and in that it comprises the transformation of the item of footwear (10) into thermoplastic granules. Method (100) according to claim 33, characterized in that the transformation step comprises:. - a step of grinding said at least one shoe to obtain ground particles; - a step of compacting said ground particles to obtain ground and compacted particles, in particular cold or hot, - a step of extrusion-granulation of said ground and compacted particles to obtain granules which can be transformed by a process of hot transformation of plastic(s). Method (100) according to claim 33 or 34, characterized in that it comprises a step of hot transformation of at least a portion of said thermoplastic granules for the manufacture of a plastic part, in particular forming at least in part an article for the practice of a sport. Plastic part, in particular forming at least in part an article for the practice of a sport, capable of being obtained by the method according to any one of claims 33 to 35, in particular said part is a fin blade. Footwear article obtained by the method (100) according to one of claims 1 to 36. Device for the manufacture of at least a portion of a footwear article (10), the device comprising a mold (1), defining an open cavity (2), a shape of at least a portion of the cavity (2) corresponding to a shape of a sole (3) of the footwear article (10), the cavity (2) being configured to receive, via at least one injection channel (4, 4', 4”, 4”') opening into the cavity (2), a mixture comprising a molten material and a supercritical fluid, a rim (5) of an opening of the open cavity (2) being configured to be placed in contact with a docking zone (6) of a surface (7) of at least a portion of an upper (9) of the footwear article (10), so that the surface (7) of the at least a portion of the upper (9) ensures a closure of the cavity at the contact between the docking zone (6) and the rim (5), so that said device is thus configured to implement the method (100) according to one of claims 1 to 36.

Images