WO1997020978A1

WO1997020978A1 - Process for printing patterns in a warp and weft textile structure, and product thus obtained

Info

Publication number: WO1997020978A1
Application number: PCT/FR1996/001819
Authority: WO
Inventors: Frédéric NOELLE
Original assignee: Icbt Perfojet
Priority date: 1995-12-01
Filing date: 1996-11-19
Publication date: 1997-06-12
Also published as: FR2741895B1; FR2741895A1

Abstract

Process for printing in and on a textile structure patterns obtained by the water jet needling technic comprising: positioning the textile structure on a perforated moving conveyor (1), formed of a warp (11) and weft (10) grid; passing said assembly in contact with a perforated rotary drum (4) of which the perforations (15) are distributed in such a way as to correspond with the patterns to be produced; and simultaneously, directing radially on the internal face of the drum a plurality of pressure water microjets (6) issued from a lower ramp (5) and which are directed to the tangent point (7) of the drum (4) and of the textile structure; characterized in that the textile structure is a warp and weft fabric; in that the perforated conveyor (1) is comprised of yarns having a diameter at least equal to 0.25 millimeters; and in that the conveyor has an undulated surface.

Description

PROCESS FOR PRINTING PATTERNS IN A CHAIN AND WEFT TEXTILE STRUCTURE, AND PRODUCT THUS OBTAINED

= Technical area

The invention relates to the field of textile finishing; it relates more particularly to warp and weft fabrics used in the field of clothing and furnishings, that is to say of low areal mass, as opposed to fabrics used in drapery. More

I _Q specifically, the invention relates to a method for printing patterns in the thickness of warp and weft fabrics. The invention also relates to this new type of fabric.

Prior techniques ι ^ In the field of clothing and furnishings, it may be advantageous to use fabrics having patterns formed in the mass and in the thickness of the fabric to give particular aesthetic effects. Thus in a conventional manner, this kind of effect is obtained by weaving using Jacquard looms which make it possible to vary

2o will armor, so as to create visual effects. Unfortunately, the creation of the patterns is a relatively complex operation, using sophisticated materials, and therefore a high cost price.

₉ 5 In the following description, the term "warp and weft fabric" means fabrics woven in which the arrangement between the parallel warp and weft son son is virtually undeformable.

Furthermore, there are known textile structures made from

3 _Q sheets of nonwoven staple fibers having patterns produced by needling techniques using water jets, as taught by the document EP-A-0 059 608 or the document FK-Λ 2 536 432 corresponding to the document US-A-4 691 417

Thus, the technique described in these documents consists in passing the textile structure consisting of a sheet of nonwoven hebrews through a needling installation by water jets. This installation comprises in particular a drum or rotating perforated cylinder in which are cut out openings corresponding to the pattern being performed and, when the web of nonwoven fibers passes under the drum, micro _j ets water I_Q through re-arrange perforations the free fibers to form the desired patterns.

It is obvious that the creation of a pattern by this method is only possible thanks to the fact that the tablecloth on which we want to print them

15 consists of free fibers of appropriate length, of the order of a centimeter, the arrangement of which can be easily rearranged by simple needling.

Conversely, it was known that the application of such a technique to a 2Q woven fabric warp and weft would be perfectly ineffective, given the relative fixity of the arrangement produced by weaving. Indeed, the fibers or filaments constituting the son are fixed, because generally assembled by twisting operations in order to give them cohesion and good resistance to abrasion. The interlacing of the threads by weaving gives the fabric strong stability.

The problem which the invention proposes to solve is that of producing patterns in the thickness of the warp and weft fabric, the arrangement of the threads of which naturally oppose the displacement of said thread. Statement of the invention

The invention relates firstly to a method for printing, and in su r a textile structure, patterns obtained by the technique ^of needling by _j ets of water comprising:

. positioning the textile structure on a moving _day conveyor, formed of a warp and weft grid,. passing this assembly in contact with a perforated rotary drum, the perforations of which are distributed to correspond to the patterns to be produced,

10. and simultaneously, directing radially on the internal face of the drum a plurality of micro-jets of pressurized water coming from a ramp of micro-perforations, directed at the point of tangency of the drum and of the textile structure,

This process is characterized:

- in that the textile structure is a warp and weft fabric,

- in that the perforated conveyor consists of wires with a diameter at least equal to 0.25 (zero point twenty-five) millimeters

- And in that the conveyor has a wavy surface state.

20

In other words, the printing process consists in subjecting a warp and weft fabric to a plurality of micro-jets of water which, thanks to the essential presence of a conveyor in the highly corrugated surface state, causes a certain modification. of the arrangement of the sons of

-) <= warp and weft at the level of the patterns to be printed.

In other words, the invention consists in using the technique of producing known patterns for nonwoven structures and in applying it to a warp and weft fabric which, by its nature of arrangement

-, Q woven, opposes the disorganization of the fibers observed and essential during the treatment of non-woven textiles. Λinsi, contrary to popular belief, I application of these micro _j ets of water causes displacement of CERTAI ns son tissue and pa rta nt 1 appearance patterns.

Of course, these patterns only appear thanks to the use of a particular conveyor in the form of wires of relatively large diameter. In fact, a grid is used, so that the weft of the weft yarns is very low and in any case very much lower than that of the warp yarns, so that the latter form sinusoids whose peaks are prominent.

To obtain patterns, it is necessary that the action of the micro-jets of water on the fabric causes, at the level of the patterns: the spacing of the warp threads by a distance corresponding substantially to the diameter of the threads of conveyor chain, and simultaneously, partial destructuring of the weft threads.

In other words, the warp threads of the fabric or more exactly the threads of the fabric parallel to the direction of movement of the machine are spaced apart when they are subjected to the combined action of the micro-jets and the conveyor.

Indeed, it is observed that the micro-jets crossing the fabric and continuing their path through a day of the grid do not produce any deformation.

On the other hand, the micro-jets which pass through the fabric and which then come into contact with an undulation of a conveyor wire are diffracted and thus cause the neighboring wires to be driven and displaced. Moreover, the weft son tissue, perpend iculaires the direction of movement of the fabric, are clamps in the area where the d _j ets are iffractés and are therefore textures. This texturing produces ruffles, either the appearance of loops or more generally a destructuring of the thread.

Advantageously, in practice, that is observed ^is obtained good results when the conveyor is woven into a taffeta weave, twill or herringbone and this in warp and weft, the son whose diameter is between 0.25 and 1.5 mm , and more precisely when the weft threads are at most equal to 1.5 mm in diameter and that of the warp threads at least equal to 0.3 mm.

This selection makes it possible to obtain optimal undulations on the surface of the conveyor, because the embuvage of the weft threads of large diameter being almost zero, the warp threads are strongly wavy and form protuberances or "knees" which allow efficient diffraction micro-jets of water.

In a particular embodiment, the warp threads of the grid forming the conveyor are made of a polyester, stainless steel or bronze monofilament.

It has also been noted that permanent patterns of good thickness are obtained when the ramp of micro-perforations by which the micro-jets are formed, is formed of two rows of micro-perforations arranged in regular staggered rows with a diameter between one hundred and. two hundred micrometers, spaced from 0.5 to 1.5 mm, the two rows being spaced by a distance of between 0.5 and 1 mm. The invention also relates to a warp and weft textile fabric, comprising alternating zones of regular density separated by zones of which the structure of the threads is disorganized in which, on the edges of the pattern, the warp threads are separated, while the threads of weft disposed between these spaced apart warp threads have ruffles or loops

In other words, patterns are obtained by disorganization, and in particular the spacing of wires in localized areas

Brief description of the drawings

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, with the support of the appended figures in which FIG. 1 is a simplified side view of a machine allowing the implementation of the process.

FIG. 2 is a greatly enlarged summary perspective view of a portion of the conveyor grid according to the invention

Figure 3 is a summary perspective view of a perforated cvhndre comprising the patterns to be printed

Figure 4 is a top view of a metal strip on which are pierced the micro-perforations generating the water jets

Figure 5 is a schematic view of detail greatly enlarged, of an elementary pattern

Finally, FIGS. 6 and 7 are reproductions of photographs taken at scale (2) of fabrics printed in accordance with the invention, respectively with hexagonal patterns and chevrons

Way of realizing the invention

As said above, the invention relates to a method for producing patterns in the thickness of a warp and weft fabric As also mentioned, this printing process can be implemented on an installation of the needling type by water jets, as described in the aforementioned documents, and on which certain parameters have been selected. There is therefore no need to describe the entire installation precisely and in detail, but simply to outline the characteristic elements of the invention.

However, the typical installation allowing the implementation of the process and the production of fabrics in accordance with the invention mainly comprises the following elements: an endless conveyor (1) set in motion by drive means (2, 3 ), a rotary cylinder (4) coming into contact with the conveyor (1), an injector ramp (5) allowing the radial emission of micro-jets of water (6) under pressure, directed towards the point of tangency ( 7) of the drum (4) with the conveyor (1), a suction box (8) connected to a vacuum source, and allowing the suction of water from the micro-jets (6) having passed through the conveyor (1 ).

The other elements of the installation not being characteristic of the invention, they will not be described here in more detail.

One of the essential characteristics of the invention resides in the structure of the conveyor (1). This is schematically illustrated in FIG. 2. This conveyor is produced from a grid woven according to a twill or chevron taffeta weave having significant porosity. As already said, in order to obtain highly imprinted patterns in the thickness of the fabric, it is important that the conveyor grid has a wavy surface condition. Thus, as shown in FIG. 2, the warp threads (11) as well as the weft threads (10) are of relatively large diameter, so that the arrangement of the warp threads (11) relative to the weft (10) forms sinusoids whose vertices (12) are as prominent as possible, so that the micro- _j ets of water (6) are well diffracted. This characteristic is manifested by a large amount of misting in the warp direction of the grid and conversely very little misting of the weft threads.

As _J to said, interesting results are obtained by using chain son (11) with a diameter of 0.5 mm and arranged in number of 8.6 per centimeter son on frame son (10) of this optimal shape, their diameter is close to 0.4 mm and their number per centimeter is 9.5.

Of course, the invention is not limited to these precise dimensional parameters, but on the contrary covers variants in which the diameter of the weft threads (10) is greater than 0.25 mm.

Regarding the materials used to form this conveyor grid

(1), various vanantes are possible, in particular grids produced from stainless steel or polyester wires, or even composite grids using these three types of materials respectively in warp and weft threads, or also grids woven in bronze threads.

Another essential characteristic of the invention resides in the use of a cylinder (4) having perforations (15) corresponding to the pattern to be printed. The variant illustrated in FIG. 3 represents perforations (15) in the form of inclined oblong holes, place the ones in relation to the other to form regular rafters. More specifically, these or oblong vertices (15) are in the embodiment shown 8 mm long by 1.2 mm wide.

Of course, ^the invention is not limited to those absolutely no grounds for rafters but of course covers all grounds Envisa eables can take all geometric forms or not, fair or not, and variable in size.

In the embodiment described, the cylinder is made of nickel, and the perforations are obtained by electro-deposition, according to a known technique.

Geometrically, the cylinder described has an external circumference of 1,621 mm for a thickness of 0.35 mm.

Regarding the injector boom (5) of the micro-jets (6), this is of conventional design and mainly comprises a cylindrical chamber in which the water pressure is greater than 100 bars, and preferably between 150 and 200 bars. This chamber (16) receives a perforated strip in its part directed towards the point of tangency (7). The band is maintained by a non-detailed hydraulic tightening system

It has been observed that the characteristics of this strip influence the quality and the thickness of the patterns obtained. Thus, this strip, shown in FIG. 4 may include one or more rows (18) of micro-perforations (17). Each of these microperforations is a circular hole 100 to 200 micrometers in diameter and is spaced from its transverse neighbors by a distance of 0.5 to 1.5 mm. In the case of the presence of several rows (17), these are spaced from 0.5 to 1 mm.

It has been observed that good results are obtained using a band

(9) stainless steel 0.8 to 1 mm thick, having two rows (17) staggered and spaced 0.6 mm. Inside these rows, the micro-perforations are 120 micrometers in diameter and spaced 0.5 mm apart.

The speed of advance of the fabric is eminently variable as a function of the surface mass of the fabric and is generally between 1 and 40 meters per minute, preferably around 10.

One of the essential characteristics of the invention resides in the fact that the textile structure treated by the needling machine is a warp and weft fabric. Of course, and as already said, this definition also extends to knits produced in such a way that the characteristics of extensibility and arrangement of the fibers are similar to those of a fabric. Given the need to move the threads of the fabric during the action of the micro-jets, it is necessary for these fabrics to be relatively fine, such as those used for the production of clothing fabrics such as a shirt or scarf, as opposed to thick fabrics used in drapery.

The process according to the invention can be applied to any type of fabric of this kind, made of natural or synthetic fiber, off-white printed or dyed. The operation of the invention is as follows, during passage of the fabric L evel the point of tangency (7) of the drum (4) with the conveyor (1), the micro-jets (6) ^when they are in front perforations (15) of the cylinder (4), come into contact and pass through the fabric. If micro _j ects, after passing through the tissue, are at the level of one day (13) of the grid, this micro-jet (6) undergoes no diffraction, and is reflected sucked by the suction box (8) . On the other hand, if after having crossed the fabric, the micro-jet (6) encounters on its path a prominence (12) of one of the warp threads (11) of the grid (1), it becomes diffracted, and this especially since the diameter of the warp thread (11) is important. It follows that the beam of diffracted micro-jets entrains the threads of the fabric adjacent to this point of impact.

The behavior of the warp threads (20) and the weft threads (21) of the fabric is different because of the direction of movement (D) of the fabric. Thus, the warp threads (20) are continuously and progressively spread apart as the micro-jet moves along the characteristic length of the top (12) of the sinusoid of the warp thread (11) of the grid (1 ).

On the other hand, the weft threads (21) situated facing the prominent areas (12) of the grid are only exposed to micro-jets (6) for a very reduced period. They are therefore not accompanied by the jets unlike the warp threads (20) and their latitude of movement is reduced. Thus, when they are clamped by the micro-jet, it causes a disorganization of the fibers or filaments forming this thread (21) and the appearance of ruffles (26), or loops, or more generally a shape texturing. The results obtained are illustrated by the photographs which are the subject of FIGS. 6 and 7. Thus, in FIG. 6, there is clearly an impression of hexagonal patterns arranged regularly. Each of these units comprises a plurality of perforated zones in which the warp son (direction of arrow "C") are slightly apart, in the manner which is schematically illustrated in Figure 5. These areas coincide with a _j ourées the projecting parts (12) of the chain son (11) of the grid (1) on which the ^water jets (6) are diffracted. The other reproduction of fabric object of FIG. 7 shows patterns obtained by the passage of the fabric under a cylinder (4) as illustrated in FIG. 3, comprising oblong openings arranged relative to each other to form effects. rafters.

It emerges from the above that the product according to the invention, in particular when it is obtained by the characteristic process, has patterns printed in its mass of a new type, never obtained by prior methods. At the fabric level, this is characterized by a good drape, a pleasant hand and a certain volume.

Industrial application possibilities

The process according to the invention and the product resulting therefrom can find a particularly advantageous application in the field of light fabrics and of clothing, or of furnishing. This method can be applied to any type of lightweight fabric, that ^it be unbleached, dyed or printed, before or after the operation characteristic of the invention.

Claims

1 / Method for printing, in and on a textile structure, patterns obtained by the needling technique using water jets consisting of:

. positioning the textile structure on a perforated conveyor (1) in motion, formed by a warp grid (11) and weft (10),. passing this assembly in contact ^with a perforated rotating drum (4) whose perforations (15) are distributed to correspond to the patterns to be produced,

10. and simultaneously, radially direct on the inner face of the drum a plurality of micro-jets of ^water (6) under pressure from a micro-perforated ramp (9), directed onto the point of tangency (7) of the drum ( 4) and of the textile structure, characterized:., C - in that the textile structure is a warp and weft fabric,

- in that the perforated conveyor (1) consists of wires with a diameter at least equal to 0.25 (zero point twenty-five) millimeters

- And in that the conveyor has a wavy surface state.

2 / A method according to claim 1, ca acterized in that the embuvage of the weft son of the conveyor is much lower than the embuvage of the warp son of said conveyor, so that the surface condition of the conveyor is wavy.

_I - 3 / A method according to claim 1, characterized in that the action of micro-water jets (6) on the fabric causes, at the grounds:

the spacing of the warp threads (20) by a distance corresponding substantially to the diameter of the warp threads (11) of the conveyor (1),

- And simultaneously the partial texturing of the weft threads (21).

30 4 / Method according to one of claims 1 to 3, characterized in that the conveyor (1) is woven in a taffeta, twill or chevron weave, and has in the weft (10) and warp (11), son of which diameter is between 0.25 (zero point twenty-five) and 1.5 (one point five) millimeters.

5 / A method according to claim 4, characterized in that the diameter of the weft son (10) is at most 1.5 (one point five) millimeter, and in that the diameter of the warp son (11) is at least 0.3 (zero point three) millimeters.

6 / A method according to one of claims 1 to 5, characterized in that the warp son (11) are made of a monofilament of polyester, stainless steel or bronze.

7 / A method according to one of claims 1 to 6, characterized in that the micro-perforated ramp (9) has two rows (17) of micro-perforations (18) arranged in regular staggered rows, of diameter between one hundred and two hundred micrometers, spaced from 0.5 (zero point five) to 1.5 (one point five) millimeters, the two rows (17) being spaced a distance compπse between 0.5 (zero point five) and one millimeter.

8 / Warp and weft textile fabric, characterized in that it alternates between zones (24) of regular density separated by zones (25) whose structure of the threads (20, 21) is disorganized in which the warp threads (20) are spread over the edges of the pattern, while the weft threads (21) arranged between these warp threads (20) that are spread apart have ruffles (26) or loops.