FR3035666A1 - TRICOTE TEXTILE STRUCTURE WITH DIFFERENTIATED ZONES - Google Patents

Abstract

This knitted textile structure is obtained by the technology knit jetty on chain loom, Rachel or hook, in one step. It comprises a central zone (101) delimited by a peripheral zone (102), said zones having different densities and / or different mechanical characteristics.

Description

FIELD OF THE INVENTION The present invention relates to a knitted textile structure having differentiated zones, more particularly in terms of the dimensions of the openings that it comprises, in terms of density, or even in terms of physicochemical characteristics. .

It is particularly applicable in the medical field, and more in the field of producing dressings intended to cover a wound or scar. It is also applicable in implants or in areas of mechanical stress or composites of parts in three dimensions.

PRIOR ART Healing brings about a certain number of phenomena leading to closure of a wound, and more particularly to restoring the continuity of cutaneous development.

For this purpose, it is known to use dressings intended to protect and / or facilitate the healing of open wounds. In the particular case of exudative wounds, such as pressure ulcers, burns, etc., the textile constituting the dressing must be peel-and-open, the size of the pores or openings, defined by the calculation of the percentage of surface area. opening relative to the total surface, being controlled to facilitate the transport of exudates out of the wound, often towards an absorbent layer. The size of the pores is adapted to the healing phase, the larger pores being used at the beginning of healing. Then, as and when the healing progresses, the pore size decreases, in order to respect the fleshy bud constituting an essential element of said healing. The surface of the textile in contact with the wound must be smooth and non-adherent, in order to avoid tearing of the healing zone at the time of the change of dressing. It is known that wound dressings made of complex composites, such as for example described in document WO 2006/044882, are capable of comprising an absorbent layer and / or a compressive layer, associated with an adhesive support intended to maintain dressing on the skin, but also to provide a wound protection function against the external environment. The various layers constituting such a complex are difficult to bond to one another, due to the fact that the textile surface in contact with the wound is most often functionalized by a release agent (see for example 10 US 2013/150763), or coated with an oil emulsion in order to preserve the entirety of the reconstructed biological tissues at the time of the dressing change, in particular during the budding phase, that is to say of proliferation cell production and extracellular matrices, that is to say, during the most critical phase of healing.

Furthermore, it results from the implementation of the dressings of the prior art a number of difficulties, among which may be mentioned: - a weakness of the mechanical properties at the periphery of the textile structure, insufficient to resist the manipulations, and insusceptible to withstand the tearing force of the dressing, likely to induce a tear at the time of change of dressing, - a weakening of the adhesive zone when using son or coating anti -adherent, making the process of making the dressing more complex and more expensive.

In the field of textile implants, more particularly used in pathologies such as urinary incontinence, parietal reinforcement (herniation, hernia), cardiovascular implants, ligamentous implants, etc., it is known to use the technology it is said to have jagged mesh, because of the possibility that it offers products that can be peeled off, besides adapting the porosity of the textile depending on the level of colonization desired for the zone to be treated. In fact, various processes and textile weaves have been described in order to obtain effective porosities (see, for example, FR 2 984 370), said porosities being identical at all points of the textile structure. It has also been described in the same application self-fixation systems of the implant, or even association with bioactive or adhesive layers in order to activate or on the contrary to deactivate cell colonization (see below). example EP 2 556 845). Whatever the purpose of these implants, the mechanical reinforcement of the latter is never discussed in terms of armor variations. SUMMARY OF THE INVENTION One of the aims of the invention is to provide a knitted textile structure, obtained by the mesh knitting technology on warp, Rachel or hook, obtained in a single step, basically aiming at defining zones. differentiated.

This knitted textile structure comprises a central zone delimited by a peripheral zone, said zones having different densities and / or different mechanical characteristics. In other words, the invention consists in producing, in a single step, by the knitting jersey technology, in particular on a warp, Rachel or crochet, a knitted textile structure defining different zones intended to perform functions. themselves different. According to an advantageous characteristic of the invention, the central and peripheral zones also have different conformational possibilities, that is to say they are capable of adopting a non-planar shape. Typically, the central zone is likely to adopt a curved shape, even though the peripheral zone is flat. This differentiation is obtained on the knitting machine by playing on the length of son absorbed, that is to say by supercharging the armor implemented, thereby generating a surplus of textile structure that can then deform . This differentiation of the characteristics of the zones, respectively central and peripheral, can also result in a variation of the dimensions of the openings or pores. Thus, and in an application more particularly intended for dressings, the central zone defines openings of dimensions greater than those of the peripheral zone or zones, and typically between 50 microns and 5 millimeters, even though the The peripheral zone has openings of dimensions typically between 25 micrometers and 3 millimeters. In this case, the healing phenomenon, and in particular the exudate exiting the so-called exudative wounds, is favored. In other applications, including in the field of dressings, this variation in dimensions can be reversed, that is to say that the peripheral zone can define openings larger than those defined by the central zone. This central zone can adopt any shape, including square, rectangle, oval, or other.

According to the invention, the central zone may be made of anti-adhesion material, and for example silicone-wrapped PET (polyethylene terephthalate); but it can also be made of resorbable materials, including bioresrobables such as PLA (polylactic acid), PLG (polyglycolic acid), PCL (polycaprolactone), chitosan. The peripheral zone is advantageously made of a material chosen from the group comprising: polyamide, polyether terephthalate (PET), polyethylene, polypropylene, PEEK (polyetheretherketone), mineral fibers (glass, basalt), but also bioabsorbable materials of the type previously mentioned in relation to the central zone. In the more particular case of the application of the invention to dressings, the peripheral zone receives on one of its faces an adhesive film, preferably by laminating or thermo-bonding, intended to ensure the joining of the dressing on the skin of a patient. In the context of the invention, it is also conceivable to produce the textile structure in the form of a sheet, defining a plurality of elementary structures, that is to say structures comprising a central zone associated with a peripheral zone. Such a sheet resulting from the knitting machine, is then cut according to the needs. In the particular case of the application of the invention to implants, the central zone consists mainly of non-absorbable materials in order to ensure the permanent and constant effect over time, and thus to ensure the function of reinforcement sought, while the peripheral zone is, for its part, made mainly of absorbable materials 5, in particular to facilitate the grip and pause. According to the invention, the density is greater in the peripheral zone than in the central zone, in order to ensure the mechanical properties of the structure.

The textile structure of the invention is capable of having an elongation extension capacity, in particular in the two directions of the plane in which it fits, typically between 5 and 170%. This variation in elongation capacity can result from the armor used.

Such a variation in elongation capacity may be advantageous for composite applications, thus allowing the structure to be adapted to complex shapes. The textile structure of the invention may also further comprise a layer 20 made of a woven, knitted or non-woven material, or even a film. This layer is secured to the structure directly on the knitting machine, in this case a Rachel trade. Thus, in the context of the application of the structure of the invention to the dressings, it becomes possible to integrate during the production of said structure, an absorbent layer, for example of the foam type, capable of containing the exudates, which and again, in one step. BRIEF SUMMARY OF THE FIGURES The manner in which the invention can be realized and the advantages which result therefrom will emerge more clearly from the following exemplary embodiments, given as an indication and not by way of limitation, in support of the appended figures, in which: FIG. 1 is a schematic representation of the knitted textile structure according to the invention implementing an elementary cell.

FIG. 2 is a diagrammatic representation of a ply resulting from a knitting machine incorporating a plurality of these elementary cells. FIG. 3 is a diagrammatic representation illustrating the various yarns and weaves used in a first embodiment. embodiment of the invention. Figure 4 is a view similar to Figure 3 of a second embodiment of the invention. DETAILED DESCRIPTION OF THE INVENTION As can be seen in FIG. 1, and according to an essential characteristic of the invention, the knitted textile structure of the invention basically comprises two zones, a central zone (101) delimited by a zone peripheral (102). According to the invention, these two zones have different densities.

This variation in densities may result from a variation in the dimensions of the apertures or pores of the respective zones. Thus, the central zone, as can be seen in FIGS. 1 and 2, has larger openings than the peripheral zone. Corollary it also has a lower density than the peripheral zone. In fact, the dimensions of the openings of the central zone may be between 50 micrometers and 5 millimeters, even though those of the openings of the peripheral zone may be between 25 micrometers and 3 millimeters.

This knitted textile structure is obtained in a single step, using the so-called chain knuckle, Rachel or crochet knitting technology. In fact, and by way of example, a three-bar wire-fed loom is used, three of which serves essentially to obtain the peripheral zone, and the two others essentially serving to obtain the central zone. During the realization of the peripheral zones, the five bars can function according to the following design: - a first bar is a bar bar, - a second bar feeds a capstan wire to ensure the mechanical properties, and 3035666 -7- - A third bar provides a total frame, necessary for the cohesion of the whole. Corollary, two bars do not mesh, so that two technical solutions 5 can be envisaged: - the first is to hide the son intended to constitute the central area, either by a capstan introduction, or by an armor to introduce straight threads, that is to say oriented production direction, without them emerging on the surface of the textile, such as for example in armor chain, 10 - the second, is to let out son in question of the structure that is to say leaving them free at the output of the knitting members, these son found in the peripheral zone in floating form, and are then cut after completion of the structure.

The embodiment of the central zone is then carried out in the following manner by way of example: two bars mesh and the armor is adapted to the geometry of the pores, in particular according to the desired shape and dimensions, such as for example in implementing a net armor.

The other three bars provide an armor so as to hide these threads in the structure, either by capstan introduction, or by an armor which makes it possible to introduce the straight threads without emerging from the surface of the textile, such as by example chain type.

According to the invention, the shape and the size of the openings, in particular of the central zone, are affected as a function of: the nature of the wires used; the mono- or multi-filament nature of the wires; - the profession's tonnage; - the density of the meshes; - selected armor; the number of knitting bars of the loom; It is conceivable when the large number of parameters thus making it possible to vary this shape and these dimensions. FIG. 2 shows a textile web (200) derived from a knitting machine operating according to the jetted knit technology, of the chain, Rachel or hook type, and defining a plurality of elementary ones incorporating each a central zone (201) and a peripheral zone (202). Such a sheet may then be cut, in order to obtain said elementary structures. FIG. 3 is thus an exemplary embodiment of the invention with bindings offering a method of construction typically adapted to the dressing function.

Thus, in the production direction, lengths respectively identified by A and B are distinguished, which can be different and adapted to the types of wounds to be treated, and generally to the desired size of the central zone. In parallel, and in the cross direction, zones of widths C and D are defined respectively. Thus, intersecting zones A and C define the central zones of the structure of the invention.

In the first exemplary embodiment illustrated in FIG. 3, the zone D, therefore limitingly constitutive of a portion of the peripheral zones, consists of wires (301) working in a chain with wires (302), which work in sectional weft. , so as to obtain a structured zone, fairly strong, that is to say, fairly mechanically resistant. Typically, these son are made of polyester, whose mechanical strength is known, and moreover, biocompatible and therefore likely to be used for medical applications. Within zone C, specific yarns (304, 305), such as polyethylene terephthalate (PET) silicone sheaths are used, said yarns working in "cellular" weave or armor or in atlas is that is to say, armor allowing to mesh diagonally evolving on different columns or needles of the knitting machine in order to create effects of "days", this on two or more rows to create the days or openings, and so to create a certain relief of this part at the same time to conceal the other threads (301, 302) relative to the background binding, necessary for the cohesion of the structure. These particular wires will reappear in the zones B to get closer to the configuration of the zones D. Moreover, wires (303, which remain in capstan, thus very discrete in the zone A, will work in sectional frame in zone B to reinforce the mechanical cohesion of the textile structure.

The particular yarns (304, 305) made of silicone-sheathed PET are in turn concealed in the capstan cross-over zone B (and therefore substantially straight), that is, in a substantially straight structure so as to be hidden and without surface contact.

In the embodiment of FIG. 4, it is also possible to provide for the appropriate separation of the yarns (404, 405) of part B. In this case, as for the manufacture of lace on a knitted loom, it is conceivable to cut these son during a complementary step called shaving or typing.

The other wires of the structure, respectively (401), (402) and (403) performing the same functions as the wires respectively (301), (302) and (303) of FIG. of the present invention which makes it possible to carry out in addition these steps, a knitted textile structure having separate zones, with distinct functions, which are particularly suitable both for application to dressings and to implants. 5 2. 10 3. 15 4. 20 5. 25 6. 30 7. 35

Claims (1)

REVENDICATIONS1. A knitted textile structure obtained by a single-stage chain-mail knitting technology, Rachel or hook, comprising a central zone (101, 201) delimited by a peripheral zone (102, 202), said zones having different densities and / or different mechanical characteristics. Knitted textile structure according to claim 1, characterized in that the respectively central and peripheral zones also have different conformations, that is to say are likely to adopt a non-planar shape. Knitted textile structure according to claim 2, characterized in that the central zone adopts a curved shape as a result of the knitting operation by varying the absorbed son length. Knitted textile structure according to one of claims 1 to 3, characterized in that the difference in densities of the respectively central and peripheral zones results from a variation in the dimensions of the openings or pores that said zones define. Knitted textile structure according to claim 4, characterized in that the dimensions of the openings of the central zone are between 50 micrometers and 5 millimeters. and in that those of the peripheral zone are between 25 micrometers and 3 millimeters. Knitted textile structure according to one of claims 4 and 5, characterized in that the openings of the central zone are square, rectangular or oval. Knitted textile structure according to one of claims 1 to 6, characterized in that the central zone is made of material with anti-adhesion properties, and in particular PET (polyethylene terephthalate) sheathed silicone. Knitted textile structure according to one of claims 1 to 6, characterized in that the central zone is made of a resorbable material selected from the group consisting of PLA (polylactic acid), PLG (polyglycolic acid), PCL (polycaprolactone), chitosan. Knitted textile structure according to one of claims 1 to 8, characterized in that the peripheral zone is made of a material chosen from the group comprising: polyamide, polyether terephthalate (PET), polyethylene, polypropylene, PEEK ( polyetheretherketone), mineral fibers (glass, basalt), but also in bioabsorbable materials of the type previously mentioned in relation to the central zone. Knitted textile structure according to one of claims 1 to 9, characterized in that the peripheral zone receives on one of its faces an adhesive film Knitted textile structure according to one of claims 1 to 6, characterized in that the area Central is mainly composed of non-resorbable materials, and in that the peripheral zone is mainly made of absorbable materials. Knitted textile structure according to one of claims 1 to 11, characterized in that it has an extension capacity yes elongation, typically between 5 and 170%. Knitted textile structure according to one of claims 1 to 12 characterized in that it further comprises a layer made of a woven, knitted or non-woven material, or even a film, associated with the structure directly on the knitting machine , and especially on a Rachel job. Use of the knitted textile structure according to one of claims 1 to 10 and 12, 13 for producing a dressing. Use of the knitted textile structure according to one of claims 1 to 6, 11 and 12 for producing an implant.