FR2852029A1 - Butt welding of coated fabrics, with a core of polymer filaments, strips the coating from the core to give thin sections as complementary steps for an overlap without distortion for welding - Google Patents

Abstract

The coated fabric, of a polymer material which can be rolled, has a butt joint of at least two basic widths (1,2) welded together at their selvedges. The fabric thickness is reduced (3,4) at the selvedge butts, as complementary steps, so that a non-reversible joint is formed at their overlap which is equal to the nominal thickness (l1,l2) of the original selvedges without distortion or bulging. The coated fabric, of a polymer material which can be rolled, has a butt joint of at least two basic widths (1,2) welded together at their selvedges. The fabric thickness is reduced (3,4) at the selvedge butts, as complementary steps, so that a non-reversible joint is formed at their overlap which is equal to the nominal thickness (l1,l2) of the original selvedges without distortion or bulging. The coating (5-8) is removed from the butting surfaces at the joint.

Description

PROCESS FOR MAKING A COATED TEXTILE. AND COATED TEXTILE THUS OBTAINED

  Technical field The invention relates to the textile industry, and more specifically to the coated textiles sector. It finds multiple applications, and in particular in the production of tarpaulins for trucks, blinds of the "banner" type, or even flexible roofing elements, or more generally in furniture or interior or exterior fittings. , as well as the digital printing sector on textile support. It relates more particularly to a coated textile which can be produced in large width, and therefore suitable for large-scale works, while being easily transportable.

  In the following description, and to facilitate understanding, the term “coated textile” will include both textiles which comprise a textile core and which are covered on at least one of their faces with a coating layer made of polymer material.

  BACKGROUND ART In general, textile fabrics, and in particular coated textiles, are transported after being wound on a generally cylindrical support which can be formed by a tube for example. This storage mode is particularly advantageous since it is very compact, and it allows both to envy the textile as soon as it is produced, and to unwind it on demand. 25 Nevertheless, the winding of the textile on a cylindrical axis can have certain drawbacks, in particular in the case where the width is particularly large.

  Indeed, for certain applications, it sometimes happens that the necessary width is greater than the maximum width that can be obtained with a loom, or the associated coating machine. In this case, it is necessary to make the wide width from elementary widths which are butted. In the case of coated textiles, such a butting is achieved by welding, at the edges of the elementary widths. At this weld, the textile thus obtained has an extra thickness, corresponding substantially to twice the thickness of the textile forming an elementary width.

  Thus, when a textile of this type is wound on a cylindrical mandrel, and in the case where the welding is carried out in the direction of the length of the textile, the additional thickness formed by the winding of the welding on itself generates the deformation of the textile. Indeed, the difference in thickness between the area of the weld and the rest of the textile aggravates the deformation of the textile as it is wound on the mandrel.

  Thus, in the case where the textile is used to form a rolling blind, the deformation of the textile generates folds in the form of chevrons around the weld, when the latter is vertical.

  This is why, to avoid this deformation, the large-width roller blinds are formed by the joining of elementary widths placed end to end, in the direction of unwinding. Each of these sections therefore has a length equal to the basic width, and is cut to the desired width for the blind. However, the presence of horizontal welds in the direction of unwinding of the blind poses an aesthetic problem, since the position of these welds is a function of the degree of unwinding of the blind. In addition, the multiplication of these welds increases the number of operations required, to the detriment of the cost price. 25 A problem which the invention proposes to solve is therefore that of allowing the winding on cylindrical mandrels, or more generally comprising a cylindrical part, of coated textiles comprising a weld perpendicular to the winding axis, and this without generate deformation on the textile.

  Furthermore, a similar problem arises when folding made-up articles. Thus, for example, when the tarpaulins of trucks are made up to the dimensions of trailers, these tarpaulins are then folded to facilitate their transport. The existence of welds having an excess thickness relative to the rest of the textile also causes deformations on the faces of the sheets, which degrade the aesthetic appearance of the sheet when it is installed.

  A second problem which the invention proposes to solve is that of the deformations which appear on articles made up from coated textiles having welds, when these are folded.

  In addition, when two widths are joined by the overlapping of their selvedge, the increase in thickness of the coating layer creates a darker area. In fact, this zone is less transparent to light, which makes darker bands appear which are detrimental to the esthetics according to the desired application.

  DISCLOSURE OF THE INVENTION The invention therefore relates to a process for making coated textile and the coated textile obtained by means of this process. The textile is coated with a polymeric material, and is produced by the joining of at least two basic widths of coated textile, welded by their selvedge.

  In accordance with the invention, this method is characterized in that there are butted 25 widths which have at their abutment edge an area of reduced thickness, so as to produce a non-reversible assembly including the abutment area has a thickness which is less than or equal to the nominal thickness of the widths.

  In other words, the invention consists in using elementary widths of coated textile which have an area of lesser thickness on their abutment edges, and then of welding them together on their edges, so that the thickness of the textile thus formed , at the weld, either less than or equal to the nominal thickness of the widths.

  According to a first embodiment, the zone of reduced thickness of the width 5 intended to be butted with a similar width is produced by the non-deposition, in this zone, of at least a fraction of a coating layer.

  In other words, when coating the fabric forming the web of the web, the coating machine can be equipped with devices which prevent the coating material from fixing in this area. This operation can be carried out during the application of a coating layer but also on a fraction of this layer.

  A width is thus obtained which has a lesser thickness over at least one area close to its edges and which is obtained by the non-deposition of a fraction 15 of a coating layer.

  According to a second embodiment, the zone of reduced thickness of the width intended for butting with an analogous width is produced by removing material, in this zone, of at least a fraction of a coating layer . In other words, once the operations for depositing the various elementary coating layers on the textile have been completed, an operation is carried out, for example trimming, aimed at reducing the thickness of the width in an area close to its edges.

  This also gives a width which has a reduced thickness over at least one area close to its edges and which is obtained by removing material from a fraction of a coating layer.

  To make the welds making it possible to obtain the textile according to the invention, compression of the weld zone is ensured, concomitantly with the weld. In this way, the non-reversible cohesion between the two widths is then ensured.

  In the case where the thicknesses of the coating layers situated on either side of the textile are equal, the thickness of the superimposed selvedges before welding is then greater than the nominal thickness of the widths. It is by means of the compression of the weld zone that the thickness between this zone and the nominal thickness of the widths is obtained.

  This welding can be carried out by a large number of techniques, and in particular ultrasonic techniques, at high frequency, by blowing hot air, or by contact with a heating resistor.

  The absence of any additional thickness over the entire width of the textile therefore allows it to be wound on a cylindrical mandrel or to be folded without any deformation or folds being caused by the welding.

  In practice, large width textiles can be produced from a single type of roller. The different widths 20 intended to be abutted are then cut from the same roll, then they are assembled so as to obtain a coated textile which comprises, in one direction, a succession of reverse and right-hand side widths of parallel orientations. Of course, the right and wrong sides can be identical or different.

  Thus, the invention finds multiple applications, and in particular for making roller blinds from coated textiles, and this in very large width, since it then suffices to join several widths lengthwise to obtain the width desired.

Brief description of the figures

  The manner of carrying out the invention as well as the advantages which result therefrom will emerge clearly from the description of the embodiment which follows, supported by the appended figures in which: FIG. 1 is an exploded section view of the junction zone of two basic widths, shown before welding.

  Figures 2 and 3 are sectional views according to two possible variants of the same junction area, shown after welding, according to the invention.

  How to carry out the invention As already mentioned, the invention therefore relates to a process for making coated textiles. This process also makes it possible to produce textiles coated by welding without extra thickness at the butting zone, in order to facilitate the operations of winding the textile.

  In accordance with the invention, two widths are butted which, in an area close to their abutment edge, have a coating layer of lesser thickness so as to produce a weld of thickness less than or equal to the nominal thickness widths.

  Thus, as illustrated in FIG. 1, two widths (1, 2) are put in place, each having at least one coating layer (5, 6, 7, 8) and of respective nominal thickness (V, -2 ). The textile core (9, 10) is produced by weaving or knitting threads, in particular glass, polyamide or polyester threads. 25 These two widths (1,2) have at their edge edge a zone of reduced thickness (3, 4), making it possible to obtain, as shown in FIG. 2, an assembly after welding whose thickness (3) is equal to the nominal thickness of the widths (X1, t2).

  According to a second variant and as shown in FIG. 3, the thickness of the assembly (e4) obtained after welding of the two widths (1, 2) can also be less than the nominal thickness of the widths (V1, t2).

  The textile thus obtained by abutment has many advantages, and in particular: * that of being able to be wound or folded without causing deformations 5 at the weld zone, due to the almost constant thickness over the entire width of the textile.

  * that of not presenting areas more opaque to light at the level of the welds between two widths. Multiple applications of tarpaulins can be envisaged, among which one can cite in addition to architectural applications in general, the winter coverings of boats or swimming pool, but also solar radiation protection devices.

Claims (9)

  1. Method for making a textile coated with a polymer material, suitable for being rolled up, comprising the joining of at least two elementary widths (1, 2) of coated textile, welded by their selvedges, characterized in that 'we butt widths (1, 2) which have at their edge edge a zone of lesser thickness (3, 4), so as to achieve a non-reversible assembly whose jointing zone has a thickness ( 3, 4) which is less than or equal to the nominal thickness of the widths (V1, f2) 2. Method according to claim 1, characterized in that the zone of reduced thickness (3, 4) of the width, intended to be butted with an analogous width, is produced by the non-deposition, in this zone (3, 4), at least a fraction of a coating layer (5, 6, 7, 8).   3. Method according to claim 1, characterized in that the zone of reduced thickness (3, 4) of the width, intended to be butted with a similar width, is produced by removing material, in this zone (3, 4 ), at least a fraction of a coating layer (5, 6, 7, 8).   4. Method according to claim 1, characterized in that the welding between two widths (1, 2) is carried out by an ultrasonic technique, at high frequency, by blowing hot air or by contact with a heating resistor.   5. Method according to claim 1, characterized in that the widths (1, 2), intended to be butted, are cut from the same roll of coated textile and then assembled so that the coated textile thus obtained comprises, in a direction , a succession of backs and places with widths (1, 2) of parallel orientations.   6. elementary width (1, 2) of textile coated with a polymer material suitable for use in the method according to claim 1, characterized in that it has, at at least one of its edges, a zone of lesser thickness (3, 4).   7. elementary width (1, 2) of coated textile according to claim 6, 5 characterized in that the zone of reduced thickness (3, 4) is obtained by the non-deposition, in this zone (3, 4), d '' at least a fraction of a coating layer (5,6,7,8).   8. Elementary width (1, 2) of coated textile according to claim 6, 10 characterized in that the zone of lesser thickness (3, 4), is obtained by removal of material, in this zone (3, 4), at least a fraction of a coating layer (5, 6, 7, 8).   9. Elementary coated textile width according to claim 6, characterized in that the threads (9, 10) of the textile core are made of polyester.   10. Textile produced by the joining of at least two elementary widths (1, 2) of textile according to claim 6, characterized in that its thickness (3, 4), in the overlapping zone of the two widths (1, 2), is less than or equal to 20 the nominal thickness (e, ú2) of the widths (1, 2).   Depositor: WEAVING AND COATING SERGE FERRARI SA Mandatory Cabinet LAURENT ET CHARRAS