IMPROVED HOOK-SHAPED FASTENING DEVICE AND METHOD

Description

GENERAL TECHNICAL FIELD

[0001] This presentation concerns the field of closure systems, and more specifically hook closure systems as well as the associated manufacturing processes and equipment. STATE OF THE ART

[0002] Hook closure systems are commonly used in various fields, including hygiene and food processing.

[0003] Hook closure systems typically include a base with hooks made of plastic material, this base being attached to a support of the product.

[0004] However, attaching the base to the product is a complex step, particularly due to the limited number of processes that allow a plastic base to be attached to a product.

[0005] Indeed, conventional processes require the use of glue, which can lead to problems in terms of cost, regularity or even reliability, and also requires the use of materials that are difficult to process and recycle.

[0006] Processes such as welding can also be considered, but are complex and expensive to implement, in addition to presenting risks to both the product and the closure system.

[0007] Document WO 2010 / 109087, filed on behalf of the applicant, presents an example of a product combining a hook-and-loop fastener and a substrate. However, this product requires the use of adhesive to bond the substrate to the hook-and-loop fastener, thus necessitating complex and bulky equipment. Document US 2005 / 0060849 presents a hook-and-loop fastener comprising multiple strips of material held together by the addition of a bottom layer, which further complicates the assembly and structure of the device.

[0008] There is therefore a need for a hook-type retention device associated with a support to simplify its integration into a product, in which the use of glue has been eliminated or at least minimized while remaining economically viable and not degrading the retention device or the product.

[0009] The present presentation aims to address these different issues. PRESENTATION OF THE PRESENTATION

[0010] This presentation concerns a restraint device, comprising an elastic film extending in a longitudinal direction, a plastic tape extending in the longitudinal direction comprising a base having a lower face and an upper face, and comprising a plurality of retaining elements extending from said upper face, characterized in that the film, base and retaining elements are formed as a single unit and produced by extrusion, and in that the elastic film exhibits a residual deformation of less than 30%.

[0011] In one example, the film, base and retaining elements are formed as a single unit by successive and / or simultaneous extrusions.

[0012] As an example, the transition between the elastic film and the base of the tape, on the top and / or bottom side, is continuous.

[0013] According to one example, the plastic tape and the elastic film forming an intermediate layer comprising a lower face and an upper face, said device further comprising a layer of non-woven material attached to at least a part of the lower face of the intermediate layer.

[0014] The bonding is then typically achieved by partial encapsulation in said intermediate layer.

[0015] Partial encapsulation is typically achieved in the elastic film of said intermediate layer.

[0016] Partial encapsulation is typically achieved within the plastic tape of said intermediate layer. Partial encapsulation can be achieved within the plastic tape of said intermediate layer and within the elastic film of said intermediate layer.

[0017] According to one example, the device further includes a non-woven layer attached to the upper face of the intermediate layer.

[0018] The non-woven layer is then typically bonded to the top face of the intermediate layer using glue.

[0019] According to one example, at least one of the lower face and / or the upper face of the intermediate layer has elements protruding from said face, which protruding elements are distinct from the retaining elements.

[0020] The protruding elements typically form bumps.

[0021] According to one example, the base of the plastic tape has a thickness of between 10 micrometers and 700 micrometers, the thickness being the distance between the upper face and the lower face, the retaining elements are each formed of a stem and a head, the stem comprising a lower end connected to the base, and an upper end opposite the lower end, the head surmounting the upper end of the stem, and comprising a lower face oriented towards the base, and an upper face opposite the lower face, and wherein the upper face of the head of the retaining elements comprises a rib.

[0022] For example, the non-woven fabric is activated. The activation of the non-woven fabric can be done prior to lamination, or the laminate can be activated across its entire width.

[0023] This also relates to a method for forming a hooked restraint device, in which A molten plastic material is dispensed into a molding device so as to form a ribbon comprising a base and retaining elements protruding from one face of said base, and a molten elastic material is dispensed. such that the plastic tape, an elastic film and the retaining elements are made in one piece by extrusion, the plastic material tape and the elastic film forming an intermediate layer, and the elastic film exhibits a residual deformation of less than 30%.

[0024] According to one example, the elastic film is formed as an extension of the ribbon.

[0025] According to an example, following the creation of the intermediate layer, a step is carried out of applying a layer of non-woven material against the underside of the intermediate layer before solidification of said underside of the intermediate layer, so as to cause portions of fibers and / or filaments of the non-woven layer to penetrate at least partially into the intermediate layer.

[0026] During the step of applying the non-woven layer against the underside of the intermediate layer, the non-woven material layer is typically at room temperature or at an unregulated temperature, and the temperature of the underside of the intermediate layer is solely due to the step of making the intermediate layer.

[0027] According to one example, the process includes a step of applying a layer of non-woven material against the top face of the intermediate layer.

[0028] The non-woven layer is then typically glued, typically via an adhesive, to the top face of the intermediate layer.

[0029] According to one example, prior to the formation of the intermediate layer, a support layer is positioned on at least part of the molding device.

[0030] According to one example, the process includes a preliminary step of activating the layer(s) of non-woven material.

[0031] According to one example, prior to the distribution of material, a molding strip is provided having an inner face and an outer face, and comprising a plurality of cavities, each cavity defining a rod extending from the outer face to the inner face, and comprising an end forming a head extending from the end of the rod towards the inner face of the molding strip, the molding strip is positioned on rotating drive means comprising for example at least two rollers, the inner face of the molding strip being disposed in contact with the drive means, the distribution of material being then carried out by a material distribution means disposed opposite the molding strip so as to define a gap between the material distribution means and the molding strip, the distribution of material being carried out so as to fill said gap and the molding material cavities in order to form a ribbon comprising a base whose thickness is defined by the gap, and first preforms protruding from said base comprising a stem and a head, the first preforms being formed by the plastic material in the cavities of the molding strip, and in which the distribution of material is followed by a demolding step in which the ribbon and the first preforms are demolded so as to plastically deform the first preforms in order to obtain second preforms whose shape is distinct from the first preforms.

[0032] Following the demolding stage, a forming stage is typically carried out in which the demolded ribbon is introduced into a forming device in order to modify the shape of the head of the second preforms by forming. PRESENTATION OF THE FIGURES

[0033] Other features, purposes, and advantages of this presentation will become apparent from the following description, which is purely illustrative and not exhaustive, and should be read in conjunction with the accompanying drawings, on which: There figure 1 schematically presents an example of equipment for the construction of a hook restraint device, The figures 2 to 10 present detailed views of the shape of the resulting retaining elements or preforms, The figure 11 uses the same equipment presented on the figure 1 and adds to it means of shaping the preforms obtained, The figures 12A to 12E And 13A to 13JThese are detailed views illustrating the steps involved in shaping the hooks, as well as the resulting hook shapes or preforms. figure 14 is a top view of the resulting ribbon illustrating the properties of the ribbon's borders. Figures 15 and 16 represent an example of equipment for assembling a substrate to a tape, for example a tape including a hook retaining device, The figure 17 schematically presents an example of a product obtained using such equipment, and The figure 18 schematically presents another example of a product that can be obtained using the equipment presented previously.

[0034] Across all figures, common elements are identified by identical numerical references. DETAILED DESCRIPTION

[0035] There figure 1 schematically presents an example of equipment for the construction of a hook restraint device.

[0036] The apparatus as represented includes a molding strip 1 positioned on rotating drive means 2 comprising here two rollers 21 and 22, a material distribution means 3 adapted to carry out an injection of molding material for example plastic and / or elastic.

[0037] The assembly formed by the molding strip 1 and the rotational drive means 2 thus forms a molding device.

[0038] The illustrated example, comprising two rollers 21 and 22, is not limiting; the number and arrangement of the roller(s) can vary, particularly to adapt to the length of the molding strip 1 and the different stations of the equipment. For example, three rollers could be used, or even just one, such that the molding strip is arranged around the periphery of that single roller. Specifically, only one of the two rollers can be driven in rotation by motorized means, for example, roller 21, while the other roller 22 remains free, i.e., without motorized means, and is driven in rotation by the molding strip, which is itself driven by roller 21.

[0039] The molding strip 1 as presented comprises an inner face 11 and an outer face 12, the inner face 11 being in contact with the rotating drive means 2.

[0040] The material distribution means 3 is arranged to inject molding material onto the outer face 12 of the molding strip 1.

[0041] More specifically, the material distribution means 3 is positioned opposite the molding strip 1, spaced from the molding strip 1 so as to define an air gap e indicated on the figure 1 . The limit of the injected material on the external face 12 of the molding strip 1 is identified by reference A, corresponding to the rear front of the injected material on the molding strip 1 with respect to the direction of movement of the molding strip 1.

[0042] The molding strip 1 is provided with a plurality of cavities allowing the making of hooks of the hooked retention device.

[0043] Each cavity 13 is formed to define a stem 14 extending from the outer face 12 to the inner face 11 of the molding strip 1, and a head 15 extending between the stem 14 and the inner face 11 of the molding strip 1. In the illustrated example, the heads 15 of the cavities 13 open onto the inner face 11 of the molding strip 1. The cavities 13 are therefore through-cavities. This embodiment is not limiting; the cavities 13 may also be blind, and therefore not open onto the inner face 11 of the molding strip 1.

[0044] The portions of the cavities 13 forming the rods 14 typically extend in a direction perpendicular to the outer face 12 of the molding strip 1. The portions of the cavities 13 forming the rods 14 typically have a rotational geometry about an axis perpendicular to the outer face 12 of the molding strip 1, or a geometry having a plane of symmetry extending in a direction parallel to the direction of scrolling of the molding strip 1 and / or in a direction perpendicular to the direction of scrolling of the molding strip 1.

[0045] The portions of the cavities 13 forming the rods 14 have, for example, a generally frustoconical or cylindrical shape of rotation around an axis perpendicular to the external face 12 of the molding strip 1, and have a rounded shape at the junction with the external face 12 of the molding strip 1.

[0046] The portions of the cavities 13 forming the heads 15 typically extend radially or transversely with respect to an axis perpendicular to the outer face 12 of the molding strip 1, and may exhibit rotational symmetry about this axis perpendicular to the outer face 12 of the molding strip 1. The portions of the cavities 13 forming the heads 15 typically have a substantially frustoconical or hexahedral shape.

[0047] The portions of the cavities 13 forming the heads 15 can be linear or curved, for example to form portions curved towards the inner face 11 or towards the outer face 12 of the molding strip 1 extending from the portions of the cavities 13 forming the stems 14.

[0048] The portions of the cavities 13 forming the heads 15 may have a constant or variable thickness.

[0049] In the example shown in the figures, the portions of the cavities 13 forming the heads 15 extend radially around the portions of the cavities 13 forming the stems 14, and have a general disc shape, as can be seen in particular on the figure 2 which will be presented later.

[0050] The molding strip 1 may have on its inner face 11 or on its outer face 12 a particular texture such as grooves, a network of grooves or a network of passages forming vents or studs, or be substantially smooth.

[0051] The molding strip 1 can be formed by a superposition of several strips, and is therefore not necessarily monobloc or monomaterial.

[0052] The material distribution means 3 is typically arranged to inject molding material into the molding strip 1 at a section of the molding strip 1 where the latter is supported against a drive roller, in this case the drive roller 21 in the example shown in the figure 1 The drive roller then forms a base for the cavities 13.

[0053] In the case where the injection of molding material is carried out while the molding strip 1 is not in contact with a drive roller, the material distribution means 3 may then include a base disposed on the other side of the molding strip 1, so that the inner face 11 of the molding strip 1 is in contact with the base when the injection of material is carried out, the base then forming a bottom for the cavities 13 of the molding strip 1.

[0054] The molding strip 1 typically has a thickness of between 5 and 5000 micrometers, or between 5 and 2000 micrometers, or more precisely between 20 and 800 micrometers, or between 100 and 500 micrometers.

[0055] The molding strip can have, in the longitudinal direction, a length of between 0.5 and 5 m.

[0056] The molding strip can have, in the transverse direction, a width of between 5 and 3,000 mm.

[0057] The rollers 21 and 22 typically each have a diameter between 10 and 10000 times the thickness of the molding strip 1, or between 50 and 5000 times the thickness of the molding strip 1, more precisely a diameter between 50 and 750 millimeters, or more particularly a diameter between 100 and 300 millimeters.

[0058] The use of a molding strip 1 associated with drive means 2 compared to the use of conventional forming means such as rollers in which molding cavities are directly made is advantageous for several reasons.

[0059] The use of a molding belt is particularly advantageous in terms of modularity. The molding belt can be easily removed and replaced from the drive means, unlike a solid roller where disassembly and reassembly are particularly complex. This advantage is especially noticeable when both rollers 21 and 22 are fixed to a frame on one side only, leaving the other end free for inserting / removing the molding belt. A molding belt guide can also be used to facilitate its insertion and / or removal.

[0060] Furthermore, manufacturing a molding strip is significantly simpler than manufacturing a roll with molding cavities. Such rolls are typically made by stacking successive layers, requiring multiple machining operations and resulting in significant stresses during assembly and each hook reference change. They also have a substantial mass, requiring the rolls to be held at both ends, which complicates their replacement.

[0061] Furthermore, the use of a molding belt coupled with drive means allows for the creation of a molding device with a significant length while maintaining simple manufacturing and installation, particularly when one of the rollers is mounted to move in translation, thus modifying the center distance between the rollers and allowing adjustment of the molding belt tension. Conversely, manufacturing molding rollers with a large diameter is particularly complex and results in molding devices with a very high mass, which therefore necessitates oversizing the entire installation to support such rollers. Moreover, manufacturing such large-diameter molding rollers does not allow for acceptable dimensional tolerances.

[0062] The various stages of forming a hook restraint device using this apparatus are now described with reference to figures 1 to 4 .

[0063] There figure 2 represents the molding material once injected into the molding strip 1. We represent on the figure 2 a side view (cross-section) of the material in the cavities 13 of the molding strip 1.

[0064] As can be seen on the figure 2 the molding material penetrates the molding strip so as to fill the cavity 13, thus forming a rough stem and head for hooks.

[0065] A layer of molding material is also deposited on the outer face 12 of the molding strip 1 so as to form a base for the retaining device, the thickness of this layer of molding material being determined by the gap e between the material distribution means 3 and the molding strip 1.

[0066] The air gap typically has a thickness between 10 and 700 micrometers, or typically between 10 and 500 micrometers, or even between 20 and 100 micrometers.

[0067] In the example shown, the cavities 13 of the molding strip 1 are through-holes. The apparatus may then include an element such as a scraper 4 positioned to scrape the inner face 11 of the molding strip 1 to remove excess molding material as needed. Injection molding refers to the process of shaping a molding material by melting, for example, dispensing, filling, molding, injection, and extrusion.

[0068] The injection of molding material into the molding strip 1 by means of material distribution 3 thus makes it possible to form a base 51 and a plurality of elements or preforms each comprising a stem 52 and a head 53, the whole thus forming a strip 100. As will be seen later, the elements comprising the stems 52 and the heads 53 are typically first preforms which will then be subjected to a forming step for the production of the hooks.

[0069] A longitudinal direction is defined relative to the direction of movement of the ribbon 100, this longitudinal direction being parallel to the direction of movement of the ribbon 100. This longitudinal direction is commonly referred to as "machine direction" or "MD" according to the English terminology. The longitudinal direction is designated by the MD axis in the figures.

[0070] We also define a transverse direction, or "cross direction" or "CD" according to the English term, corresponding to a direction perpendicular to the longitudinal direction, and extending parallel to a flat face of the ribbon 100. We designate the transverse direction by the axis CD on the figures.

[0071] The base 51 has an upper face 511 and an lower face 512 which are typically substantially parallel, the upper face 511 being the face with the hooks and / or preforms.

[0072] Base 51 typically has a thickness between 10 and 700 micrometers, or typically between 20 and 500 micrometers, or even between 50 and 100 micrometers.

[0073] The base 51 typically has a width between 1 and 3,000 millimeters, or more precisely between 2 and 400 millimeters, or even between 3 and 100 millimeters, the width of the base 51 being measured in the transverse direction relative to the longitudinal direction, for example in a direction parallel to the external face 12 of the molding strip 1.

[0074] THE figures 3, 4 and 5 illustrate three views of the hook preforms thus formed by injecting material into the molding strip 1, respectively in perspective view, top view and cross-sectional view.

[0075] We understand that these are representations of the molding material within the cavities 13, each represented isolated from the molding strip 1 to detail its shape.

[0076] As can be seen in these figures, the preforms of hooks thus formed, here the first preforms, have a stem 52 of general cylindrical or conical shape surmounted by a head 53.

[0077] We define a lower end 521 of the rod 52 connecting it to the base 51, and an upper end 522 of the rod 52 opposite the lower end 521 of the rod 52.

[0078] The head 53 extends from the upper end 522 of the stem 52.

[0079] In the example shown, the head 53 has a hexagonal shape with edges forming circular arcs. The head 53 therefore comprises a plurality of portions extending radially from the upper end 522 of the rod 52. The head 53, and more generally the assembly formed by the head 53 and the rod 52, thus exhibits rotational symmetry about an axis passing through the center of the rod 52 and the head 53. Several other shapes of the head 53 are possible; the illustrated example is intended only to demonstrate one embodiment. The head 53 can, in particular, have a hexagonal shape.

[0080] The apparatus as presented and the associated process allow operation at high ribbon formation speeds.

[0081] Indeed, conventional production lines for manufacturing hook-type retaining devices operate at reduced formation speeds, these low formation speeds being compensated for by widening the formed ribbon. This limitation in terms of formation speed stems primarily from the time required for the injected material to solidify.

[0082] The installation and process as presented, on the contrary, allow for the formation of a ribbon at a high rate, for example, exceeding 20 meters per minute, or exceeding 40, 60, 80, 100, 120, or 150 meters per minute, or between 1 and 500 meters per minute, or between 5 and 250 meters per minute. The presented process does not require complete cooling of the injected material for hook formation, and furthermore, the use of a molding ribbon with low thermal inertia, which may have through-cavities, significantly improves the ribbon's solidification rate.

[0083] According to one embodiment, the injection of molding material by the material distribution means 3 can be carried out through a sheet of non-woven material disposed on the external face 12 of the molding strip 1.

[0084] A non-woven material sheet is then placed on the outer face 12 of the molding strip 1 upstream of the material distribution means 3. This non-woven material sheet may have hollow areas facilitating the passage of the molding material, and also areas preventing the passage of the molding material.

[0085] This embodiment thus makes it possible to obtain a ribbon with a layer of non-woven material on its upper surface, i.e., on the surface with the retaining elements, i.e., the hooks. Injecting the molding material directly onto the non-woven layer then ensures strong cohesion of the non-woven material with the base 51.

[0086] Furthermore, by calibrating the distribution of hollow areas facilitating the passage of the molding material and areas preventing the passage of the molding material, a pattern for the distribution of the hooks can be defined.

[0087] The substrate in the calibrated area typically exhibits an air permeability greater than 2000 l / m² / sec, and more specifically, greater than 4000 l / m² / sec in the hook passage zone. This permeability characteristic is either intrinsic to the substrate or imparted to it through processing such as drilling, punching, needle pricking, vacuuming, embossing, or other methods. For example, the substrate could be a nonwoven material, such as a printed nonwoven. The substrate's permeability is measured, for instance, according to ISO 9237:1995 with a pressure of 200 Pa and circular specimens of 20 cm².

[0088] The basis weight of this nonwoven material is typically between 2 g / m² and 45 g / m². If the permeability of the nonwoven material is intrinsic, it can be less than 15,000 l / m² / sec, or even less than 7,500 l / m² / sec. The nonwoven material used is typically a nonwoven with a thickness between 0.10 and 0.8 mm, particularly between 0.20 and 0.60 mm. The thickness of the nonwoven material is measured, for example, according to standard NF EN ISO 9073-2:1997 using method A for normal nonwovens at a pressure of 0.5 kPa for a duration of 10 s.

[0089] The non-woven material may also exhibit locally low mechanical resistance or intrinsically low mechanical resistance such that the non-woven material is perforated by the molding material when making the hooks or preforms.

[0090] The material distribution means 3 can be adapted to distribute simultaneously or successively at least two distinct materials, thus allowing two zones made of two distinct materials to be defined in the ribbon 100.

[0091] More specifically, the material distribution means 3 can be adapted to simultaneously inject a molding material such as polypropylene for the formation of the base 51 and the hooks, and an elastic material to form an elastic profile in the extension of the base 51.

[0092] The molding strip 1 can then have shapes adapted for the different areas of the strip 100, for example have a portion with cavities 13 for the formation of preforms or hooks corresponding to the portion where the molding material is injected, and a portion without such cavities 13 corresponding to the portion where the elastic material is injected.

[0093] There figure 6 schematically represents the demolding of the 100 ribbon formed previously.

[0094] Due to the geometry of the cavities, it is understood that the heads 53 are necessarily deformed in order to allow their exit from the molding strip 1.

[0095] The portions of the cavities 13 forming the rods 14 and the heads 15 are thus dimensioned to allow passage of the heads 53 through the portions of the cavities 13 forming the rods 14 in order to carry out the demolding.

[0096] The demolding process therefore causes a deformation of the heads 53, which are schematically represented on the figure 6 This deformation can be elastic and / or plastic in nature, and can therefore lead to a modification of the heads 53 and the rods 52 in the case of plastic deformation, or the heads 53 and rods 52 can return to their initial shape after demolding in the case of elastic deformation.

[0097] The nature of the deformation depends in particular on the material used, but also on the geometry of the heads 53 and the rods 52.

[0098] To reduce the stress on the preforms during demolding, demolding is typically carried out in an area where the molding strip is not in contact with either of the rollers 21 and 22.

[0099] In the example shown on the figure 6 , we schematically represent a deformation of the head 53 which goes from a generally flat shape to a corolla shape, the portions of which extending radially or transversely from the upper end 522 of the stem 52 therefore go from a substantially flat configuration to a configuration inclined in a direction opposite to the base 51. The perimeter of the free end of the head 53 typically remains unchanged.

[0100] We then represent on the figures 7 to 10 a portion of ribbon 100 thus unmolded.

[0101] In the example shown, the demolding of the ribbon 100 resulted in a plastic deformation of the head 53, whose geometry was therefore modified in relation to the shape of the portion of cavity 13 forming the head 15.

[0102] There figure 7 is a perspective view of a portion of ribbon 100 thus demolded, the figure 8 is a top view, and the Figures 9 and 10 are two cross-sectional views along two perpendicular planes marked on the figure 7 .

[0103] As can be seen in the figures, and in particular in the Figures 7, 8, 9 and 10 The head 53, after demolding, has an asymmetrical shape; the orientation of the force during demolding causes distinct deformations on the different portions of the head 53. As shown in the Figure 10The portion of the head 53 positioned at the front (relative to the direction of travel of the molding strip 1) of the preform is here more raised than the portion of the head 53 positioned at the rear (relative to the direction of travel of the molding strip 1) of the preform; that is to say, the inclination of the portion of the head 53 positioned at the front of the preform has been modified by an angle greater than the angle by which the inclination of the portion of the head 53 positioned at the rear of the preform has been modified. This embodiment is not limiting; the head 53 can be made so as to have a symmetrical shape after demolding. This deformation of the head 53 results in the formation of a flared collar around a central portion of the head 53. This collar exhibits variations in thickness, for example, a thickness that thins out as it moves away from the stem 52.Compared to the stem 52, the distal end of the collar is thinner than its proximal end. These variations in thickness make the mechanical action of bending easier and reduce the thermal inertia required for its deformation in a subsequent step, for example during the bending and / or forming described below.

[0104] More specifically, at least one portion of the collar thus formed, when viewed in section, presents an angle A of at least 15° between the mean axis of the portion of said collar considered and a plane parallel to that of the base 51. More specifically, this angle is greater than 35°, and even more specifically, greater than 45°. On the figure 9 , angle A as shown is approximately equal to 55° and on the Figure 10 angle A is approximately equal to 80°.

[0105] Due to the formation of the collar, the maximum dimension of the head of the first preform measured in a plane parallel to the plane of the base 51 (which is called the head width) is reduced by 10% to 150%, or by 25% to 100% compared to the head width of the second preform and / or the diameter of the stem of the second preform.

[0106] The height of the head of the second preform is increased by 5% to 100%, or by 12% to 50%, compared to the height of the head of the first preform, the height being measured along a plane perpendicular to the plane of the base 51. For example, the width of the head is decreased by 0.05 mm to 0.2 mm for a stem diameter of approximately 0.2 mm, the stem diameter of the first and second preforms being virtually identical. The height of the head is increased by 0.025 mm to 0.1 mm for a stem diameter of approximately 0.2 mm, the stem diameter of the first and second preforms being virtually identical.

[0107] The injection of the molding material into the molding strip 1 is considered to form the first preforms for the hooks, each comprising a stem 52 and a head 53 (as shown, for example, on the figures 2 to 5), and that these first preforms are then plastically deformed during demolding so as to form second preforms whose shape differs from the first preforms, as shown for example on the figures 6 to 10 Plastic deformation is understood to be a residual or lasting deformation after elongation and relaxation.

[0108] In the example shown in Figures 1 , 11 And 15The demolding process is carried out using a demolding roller 6, typically configured to separate the base 51 of the ribbon 100 from the molding strip 1 under the effect of the ribbon's tension and its change of direction. The demolding roller may be equipped with a suction device and / or a surface with a high coefficient of friction, such as a rubber coating, to improve traction and limit slippage. This demolding roller may be motorized and have a tangential speed slightly higher than that of the ribbon. The separation between the ribbon 100 and the molding strip 1 is indicated in the figures by reference numeral C; this point corresponds, for example, to the point at which the base 51 of the ribbon 100 is no longer in contact with the molding strip 1.It can be anticipated that the molding strip 1 will engage with the demolding roller 6, i.e. that the demolding roller 6 will form a lever in the molding strip 1 to facilitate the demolding of the preforms and / or hooks.

[0109] The first or second preforms can then be adapted to perform a function of restraint means, or conversely not exhibit such properties.

[0110] Demolding typically occurs when the base 51 of the ribbon 100 is at a temperature lower than the melting temperature of the molding material, or lower than the heat deflection temperature of the molding material, for example when the inner face 11 of the molding strip 1 is at a temperature of approximately 45°C and the upper face 511 of the base 51 is at a temperature of approximately 75°C. The heat deflection temperature is commonly referred to by its English name "Heat Deflection Temperature" or "HDT".

[0111] The demolding stage can be followed by a forming stage, in which the second preforms are modified, particularly at the level of their head 53.

[0112] We represent schematically on the figure 11 equipment for carrying out such a forming step, and on the Figures 12 And 13two successive shape modifications can be carried out during such a forming step.

[0113] The equipment shown on the figure 11 is similar to that already depicted on the figure 1 but also includes a forming device 7 positioned downstream of the demolding roller 6.

[0114] The forming device 7 as shown comprises a drive roller 71 and two forming rollers 72 and 73.

[0115] The drive roller 71 guides and drives the ribbon 100. The forming rollers 72 and 73 perform a forming action on the stems 52 and / or the heads 53 of the preforms produced during demolding. In the example shown, the forming device 7 comprises two forming rollers 72 and 73, enabling two successive forming steps, which are described below. The forming device 7 is not limited to this embodiment and can include a variable number of rollers or, more generally, forming means to perform the desired forming steps. For example, the forming device 7 can be configured to perform only a single deformation, and thus include only one forming roller.

[0116] The forming rollers 72 and 73 are configured to exert a mechanical and / or thermal force on the heads 53 as well as on the rods 52 of the preforms, so as to induce plastic deformation in order to give a final shape to the hooks.

[0117] An example of cheesemaking is described below with reference to figures 12 to 16 .

[0118] After demolding, the ribbon 100 is driven by the drive roller 71 of the forming device 7. The forming rollers 72 and 73 are arranged so as to each define a passage between the forming roller considered and the drive roller 71 allowing the passage of the ribbon 100.

[0119] These passages between the drive roller 71 and the forming rollers 72 and 73 are dimensioned so as to have a dimension less than the height of the ribbon 100, or where appropriate the height of the ribbon 100 and the substrate, so that the forming rollers 72 and 73 exert a force on the preforms.

[0120] In the example shown, the two forming rollers 72 and 73 will allow the realization of two successive stages of deformation of the preforms.

[0121] The forming rollers 72 and 73 are each driven in rotation at rotational speeds distinct from that of the drive roller 71, and therefore also distinct from the scroll speed of the ribbon 100.

[0122] Considering the speed of the drive roller 71 as the reference speed, the first forming roller 72 has a tangential speed lower than that of the drive roller 71, for example between 5 and 200% lower than that of the drive roller 71, or between 10 and 80% lower than that of the drive roller 71, and the second forming roller 73 typically has a tangential speed higher than that of the drive roller 71, for example between 5 and 200% higher than that of the drive roller 71, or between 10% and 80% higher than that of the drive roller 71.

[0123] In addition, the forming rollers 72 and 73 are each typically maintained at a predetermined temperature depending on the molding material, for example between 75 and 165 °C or more particularly substantially equal to 120 °C for a ribbon formed from polypropylene, while the drive roller 71 is maintained at ambient temperature or at an unregulated temperature or at a temperature below the deflection temperature under load, for example below 65 °C.

[0124] These drive speed and temperature parameters cause adhesion and / or friction and / or slippage of the head 53 of the preforms on the forming rollers 72 and 73, thus causing their deformation.

[0125] THE figures 12a to 12eThese diagrams illustrate the deformation of a preform after the action of the first forming roller 72. The direction of rotation of the forming roller 72 and the direction of travel of the ribbon 100 are schematically shown by arrows. Upstream of the forming roller 72, the preform, as considered, is that presented previously with reference to the figures 7 to 10 .

[0126] We represent on the figure 12a schematically the approach of the ribbon in relation to the forming roller 72.

[0127] We then represent on the figure 12bThe schematic representation illustrates the forming action of the forming roller 72 on the preform. As seen in this figure, the forming roller 72 crushes and deforms a portion of the head 53. More precisely, the forming roller 72 comes into contact with some of the different portions of the head 53 extending from the upper end 522 of the stem 52, and brings them towards the central region of the head 53. This deformation of the preform results in a partial softening of the portion brought towards the central region of the head 53 with the material of the central region of the head 53, and also the formation of a substantially flat inclined region on one face of the head 53.

[0128] There figure 12c schematically represents the preform after the action of the forming roller 72. figures 12d and 12e present two other views, respectively in perspective and in top view of such a preform thus deformed.

[0129] As can be seen in this figure, the forming roller 72 has produced a deformation on one front of the preform, here the front of the preform relative to the direction of travel.

[0130] This deformation results in the formation of a rib extending in a direction substantially transverse to the longitudinal direction of the ribbon 100.

[0131] The deformation action exerted by the forming roller 72 causes a return of a portion of the head 53 of the preform corresponding to the front of the preform in the direction of scrolling, but this deformation action causes a flattening of the portions of the head of the preform 53 extending in the transverse direction relative to the direction of scrolling, thus forming fins extending on either side of the rod 52 in the direction transverse to the direction of scrolling of the ribbon 100. These fins define hooking portions 54 of the head 53, extending radially beyond the rod 52 of the preform, from the upper end 522 of the rod 52.

[0132] The deformation produced by the forming roller 72 forms a first rib 81 extending at least partially over the attachment portions 54.

[0133] More generally, the deformation carried out by the forming roller 72 results in the formation of a hook portion 54 and a rib extending at least partially over the hook portion 54. The rib thus formed extends over the upper face of the head 53, thus providing mechanical reinforcement of the head 53.

[0134] In the case where the head 53 includes several attachment portions 54, the forming can then result in the formation of a single rib extending continuously between the attachment portions 54, or several disjointed ribs each extending at least partially over one or more of the attachment portions 54.

[0135] Following this first deformation by the forming roller 72, a second deformation can be carried out by the forming roller 73.

[0136] THE figures 13a to 13jThese schematically represent the deformation of the preform by the forming roller 73, and the resulting shape of the hook. Indeed, the term "hook" is now used once the preforms have undergone these forming steps.

[0137] THE figures 13a and 13b represent the deformation of the preform by the forming roller 73. As can be seen in these figures, the forming roller 73 is configured to come into contact with a front portion of the preform relative to its direction of travel, and deform the head 53 of the preform.

[0138] The temperature and rotation speed parameters of the forming roller 73 cause the material of the head 53 of the preform to adhere, allowing a part of the head 53 protruding from the stem 52 to be straightened.

[0139] It is noted in particular that, with respect to the ribbon 100, the forming roller 73 has the same direction of rotation as the forming roller 72 described previously, and has a tangential speed greater than the tangential speed of the drive roller 71.

[0140] Due to these characteristics of direction and speed of rotation, the forming roller 73 deforms the head 53 of the preform in such a way as to move the material from the head 53 towards the front of the preform (relative to its direction of movement).

[0141] As a result, the forming roller 72 performs a first deformation of the preform tending to bring the material from the front of the preform towards the central part of the head 53, while the forming roller 73 performs a second deformation of the preform tending to bring the material towards the front of the preform.

[0142] The first rib 81 formed previously is thus brought forward on the preform and extends beyond the preform's stem 52. This modified first rib is identified by the reference numeral 81' in the figures. For readability, the first rib will be referred to as 81 throughout this text. A second, substantially transverse rib 82 is formed, also extending between two transverse ends of the hook, here formed by the attachment portions 54.

[0143] As can be seen on the figures 13c to 13j , the hook thus formed comprises a first rib 81 resulting from both the action of the first forming roller 72 and the action of the second forming roller 73, and a second rib 82 resulting from the action of the second forming roller 73.

[0144] These two ribs 81 and 82 each extend between two opposite ends of the hook in the transverse direction, that is to say between the two attachment portions 54 in the example shown.

[0145] Considering the direction of belt drive in the installation, a front face and a rear face of the hooks are defined. The first rib 81 extends substantially along the front face of the hooking portions 54, while the second rib 82 extends substantially along the rear face of the hooking portions 54. The hooking portions 54 thus typically comprise two distinct ribs extending at least partially over the hooking portion in question.

[0146] The attachment portions 54 and the first and second ribs 81 and 82 thus define transverse ends of the hooks having a substantially U-shaped form with a substantially flat base and whose two ribs extend in a substantially perpendicular direction.

[0147] Ribs 81 and 82 thus provide mechanical reinforcement to the hooking portions 54, the latter being configured to cooperate with complementary elements such as other hooks or loops to form a retention system. Here, "mechanical reinforcement" means that the hook is less prone to deformation under the same force when fitted with such a rib or ribs than a similar hook without such a rib.

[0148] The attachment portions 54 may extend substantially radially with respect to the rod 51, or have a free end inclined towards the base 51 as visible for example on the figures 13th , 13i or 13j , which improves the hook's holding properties.

[0149] The rib(s) 81 and 82 each extend over only a portion of the head 53. The ribs thus typically extend over only a portion of the periphery of the head 53. The ribs typically have a cumulative length of between 5 and 95% of the length of the periphery of the head 53, or more precisely between 30 and 70% of the length of the periphery of the head 53. The periphery of the head 53 is here considered to be the radial periphery of the head 53 after the hook forming step or during its formation in the molding strip 1.

[0150] In this example, at least one of the ribs 81 and 82 typically has a length greater than the diameter of the stem 52, the diameter being measured in a direction transverse to the longitudinal direction.

[0151] As can be seen in the figures, and more particularly in the figures 13d And 13hRibs 81 and 82, viewed from above the hook, each have a general inverted V (or U or C) shape comprising two branches forming an angle, this angle typically being between 90° and 180°, or more precisely between 110° and 170°, or between 140° and 150°, or approximately 145°. The two branches of the general V shape of the rib converge here towards the front of the hook. This embodiment is purely illustrative, and the general V shape can be reversed so that the rib converges towards the rear of the hook, for example by modifying the speed parameters of the forming device 7. The tip of the inverted V shape, or where applicable the apex of the U or C, can be forward in the longitudinal direction.

[0152] Ribs 81 and 82 typically exhibit symmetry with respect to a plane extending along a longitudinal direction from the base 51, passing through a central axis of the stem 52 of the retaining elements.

[0153] The hooks thus formed typically have a height of between 5 and 5000 micrometers, or between 5 and 2000 micrometers, or more particularly between 20 and 800 micrometers, or more particularly between 100 and 500 micrometers, the height being measured along a direction perpendicular to the upper face 511 of the base 51.

[0154] The head 53 can be preheated before the forming step so that it is at a temperature between the load deflection temperature of the molding material and the melting temperature of the molding material, the forming device 7 comprising a rotating element at a temperature, for example, lower than the load deflection temperature of the molding material.

[0155] As can be seen in particular on the figures 13f , 13g And 13j , the hook has a substantially flat inclined region on the face of the head arranged at the rear of the hook (relative to the direction of scrolling of the molding strip 1).

[0156] Another aspect of the device as presented concerns the regularity of the ribbon thus produced.

[0157] The injection of molding material by means of material distribution 3 makes it possible to obtain a ribbon having edges in the longitudinal direction substantially straight from the production of the ribbon, without requiring an additional cutting step.

[0158] We represent schematically on the figure 14 the 100 ribbon as described previously in top view, which ribbon includes a base and here preforms or hooks. In the example shown on the figure 14 The 100 ribbon is shown equipped with preforms as already described, particularly with reference to figures 7 to 10 .

[0159] This figure schematically represents the ribbon 100 obtained following the injection of material into the molding strip 1, this ribbon therefore extending along a longitudinal direction identified by an axis XX on the figure 14 We also represent on the figure 14The transverse direction, identified by an axis YY. The longitudinal direction identified by the axis XX is here parallel to the machine direction, that is to say the drive direction of the ribbon 100.

[0160] For this ribbon 100, we define two edges 102 and 104 extending each along the longitudinal direction, these two edges 102 and 104 defining the two ends of the ribbon 100 along a transverse direction perpendicular to the longitudinal direction.

[0161] The hooks or preforms are generally arranged near edges 102 and 104. The hooks or preforms are typically arranged at a distance D from edges 102 and 104 of between 2 and 3 hook pitches P, typically equal to 2 or 3 hook pitches P, the distance D being measured along the transverse direction relative to the longitudinal direction materialized by the axis XX on the figure 14The pitch P between two brackets corresponds to the distance between two successive brackets along the longitudinal direction. In the example shown on the figure 14 The hooks or preforms are arranged in columns extending along the longitudinal direction marked by the XX axis, these columns being repeated identically along the transverse direction. The hooks or preforms can also be arranged in a staggered or "honeycomb" pattern, for example by offsetting the columns of hooks or preforms along the longitudinal direction.

[0162] As depicted on the figure 14Each of the edges 102 and 104 exhibits a succession of rises and valleys, this succession extending along the longitudinal direction and these rises and valleys extending in a plane parallel to that formed by the base 51. These rises and valleys reflect slight irregularities in the distribution of molding material for the formation of the ribbon 100, it being understood that a perfectly straight edge is not industrially feasible. The valleys are understood to be the regions of edges 102 and 104 projecting inwards towards the ribbon 100, while the rises are understood to be the regions of edges 102 and 104 projecting outwards towards the ribbon 100. The regularity of edges 102 and 104 can therefore be assessed by means of these successive rises and valleys.

[0163] Edges 102 and 104, viewed in cross-section along a direction transverse to the longitudinal direction, exhibit a rounded portion. More specifically, this rounded shape is oriented laterally outside the base. This rounded shape is formed during the base's construction. In other words, this rounded shape was not obtained by cutting.

[0164] The apparatus and the process as presented above make it possible to obtain edges 102 and 104 of the ribbon such that for a length L along the longitudinal direction corresponding to three consecutive hills, the maximum gap E between the hills and the valleys along a direction transverse to the longitudinal direction is less than 3.0 mm, or more precisely less than 2.0 mm, or even more precisely less than 1.0 mm, or even between 0.001 mm and 1.0 mm, more particularly between 0.001 mm and 0.5 mm, even more particularly between 0.001 mm and 0.1 mm.

[0165] Such a definition is also applicable for a length corresponding to three consecutive valleys; the maximum difference between the mountains and the valleys in a direction transverse to the longitudinal direction is less than 3.0 mm, or more precisely less than 2.0 mm, or even more precisely less than 1.0 mm, or even between 0.001 mm and 1.0 mm, more particularly between 0.001 mm and 0.5 mm, even more particularly between 0.001 mm and 0.1 mm.

[0166] The 3 consecutive hills or valleys are typically over a distance less than the distance corresponding to 15 steps of hooks, preferably less than a distance of 25 mm.

[0167] Obtaining edges 102 and 104 which can thus be described as "straight" is advantageous in that it makes it possible to avoid a subsequent step of rectifying the edges, for example via a cutting step, such straight edges being perceived by the user as a sign of product quality.

[0168] Furthermore, the equipment and process employed make it possible to obtain such straight edges without requiring the formation of longitudinal ridges at the edge of the ribbon, as such ridges serve no functional purpose. The base 51 of the ribbon 100 can thus be free of a ridge extending continuously along its edges and typically exhibits a substantially constant thickness from one edge to the other. More generally, it is understood that the base 51 of the ribbon can be free of a non-functional ridge (whose sole function would be to improve the regularity of the ribbon edges), which is advantageous in terms of production since ridges lead to increased material consumption and lengthen mold occupancy time.

[0169] As can be understood from the preceding description, the straight edges are obtained via the injection of the molding material by means of material distribution 3. The subsequent demolding and forming steps maintain these straight edges as described previously, insofar as these steps do not cause the application of forces on the edges of the base 51 of the ribbon 100. The ribbon 100 thus obtained at the end of these different steps therefore has a straight edge as defined previously.

[0170] Furthermore, when at least two distinct materials are dispensed simultaneously or successively by the material dispensing means 3, the interface between the two materials is typically formed with a straight boundary, as described previously with reference to the edges of the base 51 of the ribbon 100. More precisely, when two materials are dispensed simultaneously or successively, each material is injected by the material dispensing means 3 in such a way as to form straight edges at both transverse ends of the resulting material ribbon. Consequently, the junction between the two materials is a junction between two straight edges as defined previously, and therefore has a profile that is described as straight according to the definition established earlier. The dispensing means may, for example, include two injection or extrusion nozzles.

[0171] The apparatus presented above and the associated process may also include means and a step for associating a substrate with the ribbon.

[0172] Such an association of a substrate on a tape comprising gripping elements is typically achieved by means of an adhesive, or via fusion of the base or substrate, as previously mentioned.

[0173] In order to achieve such a bonding of a substrate to the base of the ribbon, the proposed apparatus may include substrate drive means, adapted to provide substrate supply and to apply the substrate against the lower face 512 of the base 51 of the ribbon 100 downstream of the material distribution means 3.

[0174] We represent schematically on the Figures 15 and 16 an example of equipment including such means.

[0175] The apparatus as illustrated is similar to that presented previously with reference to the figure 1 Therefore, the common elements are not described again here.

[0176] As can be seen on the Figures 15 and 16 The apparatus as presented includes substrate drive means 9, here consisting of two rollers 91 and 92, configured to provide substrate 200 downstream of the material distribution means 3.

[0177] The substrate 200 is typically a layer of non-woven material, a plastic film, an elastic film, a composite film, or a thermally consolidated set of fibers and / or filaments. The substrate 200 is, for example, a sheet of fibers and / or filaments.

[0178] In the example shown on the Figures 15 and 16 The substrate is represented as a layer of non-woven material.

[0179] A nonwoven fabric is defined as a product obtained by forming a web of fibers and / or filaments that have been consolidated. Consolidation can be mechanical, chemical, or thermal and results in the presence of bonds between the fibers and / or filaments. This consolidation can be direct, meaning it is achieved directly between the fibers and / or filaments by welding, or it can be indirect, meaning it is achieved through an intermediate layer between the fibers and / or filaments, such as a layer of adhesive or a layer of binder. The term nonwoven fabric refers to a ribbon-like or web-like structure of fibers and / or filaments that are interwoven in a non-uniform, irregular, or random manner. A nonwoven fabric can have a single-layer or multi-layer structure. A nonwoven fabric can also be bonded to another material to form a laminate.A nonwoven fabric can be made from various synthetic and / or natural materials. Natural materials, for example, are cellulose fibers, such as cotton, jute, flax, and similar materials, and may also include reprocessed cellulose fibers, such as rayon or viscose. Natural fibers for a nonwoven material can be prepared using various processes, such as carding. Synthetic materials, for example, include, but are not limited to, synthetic thermoplastic polymers, which are known to form fibers that include, but are not limited to, polyolefins, such as polyethylene, polypropylene, polybutylene, and similar materials; and polyamides, such as polyamide 6.6, polyamide 10, polyamide 12 and similar materials; polyesters, for example polyethylene terephthalates, polybutylene terephthalates, polylactic acids and similar materials, polycarbonates, polystyrenes, thermoplastic elastomers, polymeric vinyls, polyurethanes and mixtures and copolymers thereof. By way of example, nonwoven fabrics may be spunbond, spunmelt, thermally bonded carded, SMS, SMMS, SS, SSS, SSMMS, SSMMMS, air-through, or other types.

[0180] The substrate is not limited to a non-woven material, and can more generally be a non-woven material, a woven material, a knitted material, or a combination of several of these materials.

[0181] The substrate drive means 9 are configured to supply the apparatus with substrate 200 and apply this substrate 200 against the lower face 512 of the base 51 of the ribbon 100 downstream of the material distribution means 3. The substrate drive means 9 are configured so that this application is carried out prior to the solidification of the base 51 of the ribbon 100. Thus, this application results in at least partial penetration of the substrate 200 beyond a plane defined by the lower face 512 of the base 51 of the ribbon 100. The point of contact between the base 51 of the ribbon 100 and the substrate 200 is identified by reference numeral B in the figures.

[0182] More precisely, the lower face 512 of the base 51 is substantially flat and defines a plane. Applying the substrate against this face results in the penetration of portions of the substrate 200, for example, fibers and / or filaments of the non-woven material layer in the case where the substrate 200 is a non-woven material layer within the base 51, thus passing through the lower face 512 of the base 51. This is schematically represented on the figure 17 an example of a product resulting from this bonding between the ribbon 100 and the substrate 200.

[0183] Insofar as such an application is carried out prior to the solidification of the base 51 of the ribbon 100, it is not necessary to heat the base 51 of the ribbon 100 and / or the substrate 200 in order to achieve such a bond.

[0184] For example, considering a base 51 made of polypropylene, the substrate is typically applied to the underside 512 of the base 51 when the underside 512 of the base 51 has a temperature between the melting point of the material and its Vicat softening point B minus 30°C, or between the melting point of the material and its Vicat softening point A. More specifically, when the base is made of a polypropylene-based material, the underside 512 of the base 51 has a temperature between 75°C and 150°C, typically around 105°C, this temperature being typically measured using an infrared or laser camera.The VICAT softening temperature is defined as the temperature obtained according to one of the methods described in ISO 306 or ASTM D 1525 standards with a heating rate of 50°C / h and a standardized load of 50N for VICAT B and a standardized load of 10N for VICAT A.

[0185] More generally, when the substrate 200 is applied against the lower face 512 of the base 51, the lower face 512 of the base 51 is at a temperature below its melting point, or more particularly below the deflection temperature under load of the material forming the base 51, or essentially equal to the ambient temperature (or an unregulated temperature), and the temperature of the base 51 results solely from the ribbon 100 formation step. Considering the points A, B, and C defined previously and visible in particular on the figure 15The distance traveled by the base 51 between points A and B is typically between 20.0 mm and 400 mm. Similarly, the distance traveled by the base 51 between points B and C is typically between 400 mm and 1500 mm. The distance traveled by the base 51 between points B and C is typically twice the distance traveled by the base 51 between points A and B.

[0186] The roller 92 is typically configured to apply the substrate 200 under pressure against the lower face 512 of the base 51 in order to facilitate the penetration of the substrate 200 into the base 51.

[0187] The roller 92 may have patterns or reliefs on its surface, so as to promote the penetration of the substrate 200 into the base 51.

[0188] The substrate 200 can be applied uniformly or non-uniformly against the lower face 512 of the base 51.

[0189] The bond made between the substrate 200 and the base 51 of the ribbon 100 can be made in a uniform or non-uniform manner.

[0190] In the case where the substrate 200 is a set of thermally consolidated fibers and / or filaments, the bond with the base 51 is also achieved by penetration into the base of a part of the fibers and / or filaments of the substrate 200.

[0191] In cases where the substrate 200 is a thermally bonded assembly of fibers and / or filaments, a plastic film, an elastic film, or a composite film, shrinkage may occur in the ribbon 100 during its cooling as it bonds to the base. This shrinkage increases the bonding surface between the substrate and the ribbon base. This shrinkage has no impact on the visual appearance for the end user.

[0192] More specifically, it is well known that molded parts exhibit shrinkage or cavities during material cooling. In this case, the ribbon 100 has sections of varying thickness due to the presence of retaining elements extending from the upper face 511 of the base 51. These areas of excess thickness will cause material shrinkage vertically along the shanks 52 of the hooks, thus forming shrinkage zones 530 in the lower face 512 of the base 51.

[0193] However, since the substrate 200 is applied against the lower face 512 of the base 51 prior to the solidification of the base 51, this material shrinkage occurs after the substrate has been applied to the lower face 512 of the base 51. The pressure applied by the substrate 200 against the lower face 512 of the base 51, and the fact that the base 51 is not yet solidified during this application, results in adhesion by molecular interdiffusion between the substrate 200 and the lower face 512 of the base 51. Thus, during the material shrinkage of the base 51 during its solidification, as mentioned previously, the substrate 200 remains in contact with the lower face 512 of the base 51, and regions of the film forming the substrate 200 therefore conform to the shape of the material shrinkage zones in the lower face 512 of the base 51. These regions of the film forming the substrate 200 thus penetrate beyond of the plane defined by the lower face 512 of the base 51.Thus, the surface area of ​​the film forming the substrate 200 in contact with the lower face 512 of the base 51 is greater than the projection of the surface of the film onto a plane defined by the lower face 512 of the base 51, which makes it possible to increase the adhesion between the substrate 200 and the ribbon 100.

[0194] If the substrate 200 is a layer of non-woven material, the hooks can be easily demolded even with a non-woven material weighing less than 80gsm. For example, the non-woven material's weight can range from 5gsm to 120gsm, or even from 10gsm to 70gsm.

[0195] In the case where the substrate 200 is a layer of non-woven material, the apparatus may include a calendering device upstream of the substrate drive means 9, thus allowing a calendering step to be carried out locally or not of the layer of non-woven material prior to its application against the tape 100.

[0196] This method of bonding a substrate 200 to a ribbon 100 is particularly advantageous in that it does not cause deformation of the ribbon 100, and therefore advantageously allows the shape of the base 51 obtained during the injection step to be preserved, and in particular the straight edges that can be obtained via the process and equipment described above.

[0197] This method of bonding a substrate to a tape can be applied to a tape formation process as described above, or more generally to any other tape formation process including retaining elements such as hooks.

[0198] The various devices and processes described above can be used independently or in combination.

[0199] As an example, the following is described with reference to the figure 18 a product that can be obtained via the equipment and processes described above.

[0200] There figure 18 Product 300 is presented, comprising a ribbon 100 made of plastic material. The ribbon 100 is formed in one piece with an elastic film 310 by extrusion. More specifically, the plastic ribbon 100 is formed in one piece with an elastic film 310 by simultaneous or successive extrusions. "Successive extrusions" here refers to the fact that the film 310 and / or the ribbon 300 are produced in the same continuous process as the ribbon 300 and / or the film 310, or on the same production line.

[0201] There figure 18 is a cross-sectional view along a plane perpendicular to the longitudinal direction of the product 300 formed.

[0202] The 100 ribbon is similar to the ribbon as previously described, and comprises a base 51 and hooks extending from the upper face 511 of the base 51.

[0203] The elastic film 310 was extruded simultaneously, successively, or prior to the extrusion of the ribbon 100 by the material distribution means 3, thus defining a bond between the ribbon 100 and the film 310 along one of their transverse ends. The transition between the elastic film 310 and the base 51 of the ribbon 100 is therefore typically continuous.

[0204] Thus, the elastic film 310, the base, and the retaining elements of the plastic ribbon 100 are made from a single piece of extruded material. The numerical reference 320 designates the interface between the elastic film 310 and the ribbon 100.

[0205] The term "one-piece" refers to the fact that the tape and the film are bonded solely by simultaneous or successive material distributions, for example, by simultaneous or successive extrusions. In other words, the bond is formed only by intramolecular diffusion from the tape to the elastic film and / or from the elastic film to the tape.

[0206] This interface 320 can be made along a plane substantially parallel to the longitudinal direction of the product 300 as shown in the figure 18 , or create an overlap between the elastic film 310 and the tape 100.

[0207] When the hooks and the base are made of the same material, there is a continuity of material from the base to the hooks and vice versa. In other words, the material forming the hooks and the material forming the base are contiguous.

[0208] For the elastic film 310, we define an upper face 311 and a lower face 312. According to the example shown in the figure, the upper face 311 of the elastic film 310 is here in line with the upper face 511 of the base 51 of the ribbon 100. According to the example shown in the figure 18 , the lower face 312 of the elastic film 310 is here in the extension of the lower face 512 of the base 51 of the ribbon 100.

[0209] The assembly formed by the elastic film 310 and the tape 100 thus constitutes an intermediate layer, presenting a lower face and an upper face.

[0210] As can be seen on the figure 18 , a substrate 200 is attached to the lower face of the intermediate layer, i.e. to the lower face 312 of the elastic film 310 and to the lower face 512 of the base 51 of the ribbon 100.

[0211] Substrate 200, for example, is a non-woven material, as described previously.

[0212] The substrate 200 is bonded to the intermediate layer by partial encapsulation within said intermediate layer, that is, by partial encapsulation of the substrate in the base 51 of the tape 100 and in the elastic film 310. This bonding is achieved using the method and apparatus already described previously with reference to figures 15 to 17 .

[0213] The product 300, as presented, also includes a support layer 330 bonded to the upper surface of the intermediate layer. This support layer 330 extends over the upper surface 311 of the elastic film 310, and also at least partially over the upper surface 511 of the base 51 of the tape 100.

[0214] The support layer 330 may be of the same composition as the substrate 200, or of a different composition; for example, it may be a layer of non-woven material, a knit or a grid.

[0215] In the example shown, the support layer 330 is bonded to the top surface of the intermediate layer. This is schematically represented on the figure 18 a layer of glue 340 extending over the upper face 311 of the elastic film 310 and also partially over the upper face 511 of the base 51 of the tape 100.

[0216] The support layer 330 is then typically bonded to the upper face of the intermediate layer after the substrate 200 has been bonded to the lower face of the intermediate layer.

[0217] It is understood that this method of bonding is only illustrative, and that any other suitable method can be used to bond the support layer 330 to the upper face of the intermediate layer.

[0218] The support layer 330 can for example be placed on the molding strip 1 prior to the distribution of material by the material distribution means 3, so that the plastic and elastic material is injected onto the molding strip while the support layer 330 is positioned on the molding strip 1, as mentioned previously.

[0219] The upper and / or lower face of the base 51 of the tape 100 and / or the elastic film 310 may be smooth (except for the hooks) or not. They may, for example, have raised features, such as transition elements, removed hooks, recesses such as holes, slots, or projections such as studs, points, domes, and / or peaks. These raised features may have a height that is less than the height of the retaining elements, more specifically less than 40% of the height of the retaining elements, and more specifically, less than 25% of the height of the retaining elements. Such raised features may be advantageous in certain applications, for example, to define areas with distinct roughness or a different surface appearance, offering practical and / or aesthetic benefits.

[0220] In the case where the substrate 200 and / or the support layer 330 is a non-woven, the substrate 200 and / or the support layer 330 can be activated prior to its bonding to the intermediate layer, as indicated previously.

[0221] Plastic material is understood to mean a thermoplastic material, more particularly a polyolefin material based on homopolymer or copolymer.

[0222] As an example, the list of plastic materials includes: LLDPE (Linear Low Density Polyethylene), LDPE (Low Density Polyethylene), m-PE (Metallocene Polyethylene), HDPE (High Density Polyethylene), EVA (Ethylene Vinyl Acetate), and PP (Polypropylene), comprising a unimodal or multimodal (e.g., bimodal) molecular weight distribution, in particular a composition comprising LLDPE and a plastomer, especially a polyethylene-based plastomer. Polyamide (PA), polylactic acid (PLA), polyhydroxyalkanoates (PHA), PVOH, and PBS could also be used.

[0223] An elastic material is defined as a material adapted to be stretched under a lateral tensile force and to substantially return to its original shape and dimensions after the tensile force is released. For example, it is a material that retains a residual deformation or set after elongation and release (residual deformation, also called "permanent set" or "SET") of less than 30%, or less than 20%, or, for example, less than 5%, of its original dimension (before elongation) for an elongation of 100% of its original dimension, at room temperature (23°C). The SET can be measured as described in patent application EP1783257, the contents of which are incorporated by reference, and in particular paragraphs

[0056] to

[0062] of publication EP1783257A1, which detail an example of SET measurement.

[0224] Examples of elastic materials include styrene / isoprene (SI), styrene / isoprene / styrene (SIS), styrene / butadiene / styrene (SBS), styrene-ethylene / butylene-styrene (SEBS), styrene-ethylene / propylene-styrene (SEPS), and SIBS copolymers. Blends of these elastomers with each other or with non-elastomers that modify certain characteristics other than elasticity can also be considered. For example, up to 50 percent by weight, but preferably less than 30 percent by weight, of polymer may be added to modify certain characteristics of the base materials (elasticity, heat resistance, processability, UV resistance, color, etc.), such as polyvinyl styrene, polystyrene or poly α-methyl styrene, epoxy polyesters, polyolefins, for example polyethylenes or certain ethylene / vinyl acetates, preferably those of high molecular weight.

[0225] The elastic material may be, in particular, a styrene-isoprene-styrene, available, for example, from Kraton Polymers under the name KRATON D (Registered Trademark), or from DEXCO POLYMERS LP under the name VECTOR SBC 4211 (Registered Trademark). Thermoplastic elastomer (TPE) materials may also be used, in particular a thermoplastic polyurethane elastomer, notably PELLETHANE (Registered Trademark) 2102-75A from The Dow Chemical Company. A styrene-butadiene-styrene material may also be used, notably KRATON D-2122 (Registered Trademark) from Kraton Polymers, or VECTOR SBC 4461 (Registered Trademark) from Dexco Polymers LP. One can also use a styrene-ethylene / butylene, in particular KRATON G-2832 (Registered Trademark) from Kraton Polymers, or a sequence copolymer styrene-ethylene-butylene-styrene (SEBS), in particular KRATON (Registered Trademark) G2703.One can also use a copolymer of isooctyl acrylate and acrylic acid with monomer ratios of 90 / 10. One can also use a sequence polyamide polyester copolymer PEBAX (Registered Trademark) 2533 from the company Arkema.

[0226] Other possible materials are polyolefin polymers, mainly ethylene and / or propylene copolymers, having characteristics of elastomers, especially those produced by metallocene catalysis, such as VISTAMAXX VM-1120 (Trademark), available from Exxon Mobil Chemical, or polymers filled with rubber, such as Santoprene filled with EPDM.

[0227] Materials can also be used to promote bonding between the plastic and elastic materials. As an alternative embodiment, each cavity in the molding strip could have a rod extending from the top to the bottom of the molding strip.

[0228] Various systems and methods compatible with the present exposition are described in patent applications FR 16 53866, FR 16 53870, FR 16 53872, FR 16 53873, FR 16 53888, FR 16 53894 and FR 16 553897.

Claims

1. A retaining device (300) with hooks, comprising: • an elastic film (310) extending in a longitudinal direction; and • a plastics tape (100) extending in the longitudinal direction comprising a base (51) presenting a bottom face (512) and a top face (511) and including a plurality of retaining elements extending from said top face (511); characterized in that the film (310), the base (51), and the retaining elements are formed integrally by means of extrusion, and in that the elastic film (310) presents residual deformation that is less than 30%, measured according to the method presented in the description.

2. A retaining device (300) according to claim 1, wherein the film (310), the base (51), and the retaining elements are formed integrally by successive and / or simultaneous extrusion operations.

3. A retaining device (300) according to claim 1 or claim 2, wherein the transition between the elastic film (310) and the base (51) of the tape (100), beside the top face and / or the bottom face, is continuous.

4. A retaining device (300) according to any one of claims 1 to 3, wherein the plastics tape (100) and the elastic film (310) form an intermediate layer having a bottom face and a top face, said device further comprising a layer of nonwoven material (200) secured to the bottom face of the intermediate layer.

5. A retaining device (300) according to claim 4, wherein the securing is performed by partial encapsulation of the layer of nonwoven material (200) in said intermediate layer.

6. A retaining device (300) according to claim 5, wherein the partial encapsulation is performed in the plastics tape (100) of said intermediate layer.

7. A retaining device (300) according to any one of claims 1 to 6, further comprising a support layer (330) secured to the top face of the intermediate layer, for instance by means of an adhesive.

8. A retaining device (300) according to any one of claims 4 to 7, wherein at least one of the bottom face and / or of the top face of the intermediate layer presents elements projecting from said face, which projecting elements are distinct from the retaining elements.

9. A retaining device (300) according to claim 8, wherein the projecting elements are in the form of spikes.

10. A retaining device (300) according to any one of claims 1 to 9, wherein the base of the plastics tape (100) presents a thickness lying in the range 10 µm to 700 µm, where the thickness is the distance between the top face (511) and a bottom face (512) of the base (51), and wherein each of the retaining elements is constituted by a stem (52) and by a head (53), the stem (52) having a bottom end (521) connected to the base (51), and a top end (522) opposite from the bottom end (521), the head (53) surmounting the top end (522) of the stem (52), and having a bottom face facing towards the base (51) and a top face opposite from the bottom face, and wherein the top face of the head (53) of each retaining element includes a rib (81, 82).

11. A method of forming a retaining device (300) with hooks, wherein: • a plastics material in the molten state is dispensed in a molding device (1, 2) so as to form a tape (100) having a base (51) and retaining elements projecting from a face of said base (51); and • an elastic material in the molten state is dispensed; in such a manner that the plastics tape (100), an elastic film (310), and the retaining elements are made integrally by extrusion, the tape of plastics material (100) and the elastic film (330) forming an intermediate layer, and the elastic film (310) presents residual deformation that is less than 30%.

12. A method according to claim 11, wherein the elastic film (310) is formed to extend the base (51) of the tape (100).

13. A method according to any one of claims 11 to 12, including a step of applying a support layer (330) against the top face of the intermediate layer, the support layer (330) being for example made of nonwoven material.

14. A method according to any one of claims 11 to 13, wherein prior to forming the intermediate layer, a support layer (330) is positioned on at least a portion of the molding device (1).

15. A method according to any one of claims 12 to 14, wherein prior to dispensing material, a molding strip (1) is provided presenting an inside face (11) and an outside face (12), and having a plurality of cavities (13), each cavity (13) defining a stem (14) extending from the outside face (12) towards the inside face (11), and including an end that forms a head (15) extending from the end of the stem (14) towards the inside face (11) of the molding strip (1), the molding strip (1) is positioned on rotary drive means (2), e.g. comprising at least two rollers (21, 22), the inside face (11) of the molding strip (1) being arranged to press against the drive means (2); • molding material is then dispensed by material dispenser means (3) arranged facing the molding strip (1) in such a manner as to define a gap between the material dispenser means (3) and the molding strip (1), the molding material being dispensed in such a manner as to fill said gap and the cavities (13) with molding material so as to form a tape (100) comprising a base (51) of thickness that is defined by the gap, and first preforms projecting from said base (51), each comprising a stem (52) and a head (53), the first preforms being formed by the plastics material in the cavities (13) of the molding strip (1); and wherein the dispensing of material is followed by an unmolding step in which the tape (100) and the first preforms are unmolded in such a manner as to deform the first preforms plastically so as to obtain second preforms of shape that is different from the shape of the first preforms.