EP0853152B1 - Process to produce an extensible fabric for use as a seat cover - Google Patents

Abstract

In the method for producing a fabric that is extendible in both the warp and weft directions and which exhibits colour effects, the warp and weft yarns being synthetic yarns that have been subjected a false twist type texturing treatment to render them both voluminous and extendible, the textured yarns forming the warp and/or the weft are dyed prior to forming into the fabric under conditions such that the yarns can contract during the dyeing operation. The weave of the fabric is designed such that the raw fabric is decontextured in the warp and the weft with respect to the desired density in the finished fabric. It then involves carrying out a weaving operation while maintaining the warp and weft yarns under tension. After the weaving operation, the raw fabric is washed at a temperature of below 100 degrees C to avoid washing out of the colourants, then subjected to a thermal finishing treatment by passage on a tenter frame, these operations being carried out under conditions which cause a contraction of the crimp of the yarn which in turn causes a retraction of the fabric in both the warp and the weft directions.

Description

The present invention relates to an improved process making it possible to produce a new type of stretch fabric both in the warp direction and in the weft direction, and more particularly a fabric which can be used as seat coverings, automobile seats in particular.

It is known that the materials used to produce seat covers, in particular in the automobile sector, must not only have very good resistance to abrasion under pressure, but must not deteriorate over time under the influence heat, solar radiation ....

Furthermore, the complex shape that the seat and the seat back can have to improve the comfort and support of the driver's body, means that more and more stretchy textile structures are used to produce such coverings. .

To date, as materials, mainly fabrics obtained by knitting are used and more particularly those made according to the technique known as “with picked stitches” which are, by the very fact of the interweaving of the stitches one in the other, slightly stretchable even if the threads used to make them do not have such a property.

Although very many proposals have been made to date for making stretch warp and weft fabrics which can be used more particularly in the clothing sector (see in particular DE 2845919), their use as seat coverings has not developed, which can be explained by the fact that they do not make it possible to simultaneously solve all of the problems recalled previously, in particular as regards resistance to friction.

Among the stretch fabrics offered to date, two main families can be mentioned.

The first, which makes it possible to obtain articles which can have a very high extensibility, which can reach up to 40%, consists in making the fabric from gimped, assembled or equivalent threads, the core of which consists of a thread. belonging to the class of elastofibers, elastane for example, and the coating of which may consist of either a fiber spun or a synthetic thread, possibly textured in particular by false twist.

These gimped threads undergo an appropriate heat treatment which temporarily blocks their extensibility thus making them suitable for weaving, the extensibility of the fabric being revealed during a subsequent finishing treatment.

Such a procedure however poses implementation problems, in particular to obtain the retraction of the wire during the heat treatment, retraction which can cause defects in the tissue, blistering in particular, requiring a new treatment to bring the tissue flat.

If such articles may be suitable for the production of seat coverings given their very high extensibility, they are however not adapted by the fact that the elastic core can degrade over time, and above all that they have a resistance insufficient friction for such an application.

Furthermore, fabrics based on elastomeric yarns (core yarns) also have a major drawback, namely their high price which results, both from the materials which go into their composition, and from the molding operations necessary for obtaining them and they pose problems during their handling, especially dyeing.

It has also been proposed, still in the field of clothing, to make warp and weft fabrics having very good extensibility, up to 15%, using synthetic threads, in polyamide or polyester for example, having received a treatment. texturing, notably by false twist.

Such fabrics made from textured yarns can be produced at a very competitive price. From a practical point of view, these products are however mainly used in the field of clothing and have not found application in the field of seat covers. Furthermore, this type of article is generally dyed in pieces, which makes it possible to produce only plain or semi-plain fabrics, and does not make it possible to obtain colored designs.

Now we have found, and this is what is the subject of the present invention, an improved process which makes it possible to produce stretch fabrics both in the warp direction and in the weft direction, fabrics which have colored effects, and this from threads textured by false twist called “foam threads” which have not received any additional heat treatment, making it possible to limit their extensibility.

• · les fils texturés formant la chaîne et/ou la trame sont préalablement teints avant l'opération de transformation en tissu, et ce dans des conditions entraînant la rétraction desdits fils;
• · le tissage est réalisé pour que le tissu écru présente une densité en fils de chaîne et de trame inférieure de 10 à 15% de la densité finale souhaitée dans le tissu fini ;
• · l'opération de tissage est réalisée en maintenant les fils de chaîne et de trame sous tension ;
• . après tissage, le tissu écru est soumis à une opération de lavage à une température inférieure à 100°C éliminant tout risque de dégorgement des matières colorantes, puis à un traitement thermique de finition par passage sur rame, ces opérations étant réalisées en maintenant le tissu sans tension tant en long qu'en large, provoquant une contraction de la frisure des fils entraînant une rétraction de l'étoffe tant dans le sens chaîne que dans le sens trame.

In general, the method according to the invention for the production of a fabric which can be stretched both in the warp direction and in the weft direction, and which has colored effects, the warp threads and the weft threads being synthetic yarns having received a texturing treatment by false twist, making them both bulky and extensible, the method according to the invention is characterized in that:

• · The textured yarns forming the warp and / or the weft are dyed beforehand before the transformation operation into fabric, and this under conditions causing the retraction of said yarns;
• · The weaving is performed to the unbleached fabric has a density in warp son and lower frame 10 to 15% of the desired final density in the finished fabric;
• · The weaving operation is carried out while keeping the warp and weft threads under tension;
• . after weaving, the unbleached fabric is subjected to a washing operation at a temperature below 100 ° C. eliminating any risk of bleeding the dyestuffs, then to a finishing heat treatment by passing over a ream, these operations being carried out while maintaining the fabric without tension both in length and in width, causing a contraction of the crimp of the threads causing a retraction of the fabric both in the warp direction and in the weft direction.

According to a preferred embodiment, the fabric obtained by the process according to the invention is produced from polyester threads textured by false twist. In such a case, to carry out the dyeing operation, the threads are in the form of soft spools allowing the thread to shrink during the dyeing operation which, preferably, is carried out in an autoclave at a temperature of the order 130 ° C.

Such a fabric can be based on any type of weave, whether plain, fancy, or even Jacquard.

Furthermore, when producing the unbleached fabric, the density of warp and weft threads is calculated to be approximately 10 to 15% less than the final density desired in the finished fabric.

As indicated previously, the washing operation is carried out so as not to affect the coloring of the threads, a temperature of 90 ° C. being suitable in the case of polyester threads previously dyed, the finishing heat treatment (treatment on the ream) being as for him realized on an installation inside which reigns a temperature of 150 ° C, but which, taking into account the speed of passage of the fabric which is of the order of 15 m / minute, makes that this last n 'meanwhile reaches a temperature of the order of 130 ° C.

By proceeding in this way, a fabric is obtained which can be stretched both in the warp direction and in the weft direction, having an extensibility of the order of 20% and which, moreover, has improved abrasion resistance. compared to the previous warp and weft fabrics, extensible, made of textured threads and which are intended for clothing.

The invention and the advantages which it brings will however be better understood thanks to the exemplary embodiments given below for information but not limitation.

Example 1

• · Chaîne : fils polyester texturés par fausse torsion, chaque fil comportant deux bouts de 167 dtex30 brins, ayant été préalablement teints. La chaîne comporte 4498 fils et est réalisée avec une disposition de couleurs (trois coloris). Le peigne du métier comporte 13 dents/centimètre avec deux fils par dent, soit 26 fils par centimètre.
• · Trame : fils polyester texturés FT similaires aux fils de chaîne. Les fils de trame sont également teints.

A fabric is produced in accordance with the invention, the warp and weft constituents of which are as follows.

• · Warp : polyester threads textured by false twist, each thread comprising two ends of 167 dtex30 strands, having been previously dyed. The chain has 4498 threads and is made with a color arrangement (three colors). The loom comb has 13 teeth / centimeter with two wires per tooth, or 26 wires per centimeter.
• Weft : FT textured polyester threads similar to warp threads. Weft threads are also dyed.

Weaving is carried out by keeping the warp threads under tension, the weft being inserted also under tension at the rate of 20 strokes / centimeter.

When the loom falls, the fabric obtained has a width of 152 centimeters and weighs 230 grams / square meter.

Such an ecru fabric has a 10% long and wide stretch.

The unbleached fabric thus produced is subjected to a treatment making it possible to amplify these extensibility properties, treatment which consists first of all of a washing operation at a temperature of 90 ° C. carried out on a machine of the “Jet” type, treatment during which the fabric is kept tensionless both long and wide. The washing temperature is such that on the one hand, it does not affect the qualities of the dyeing produced on the threads, and does not cause thermal fixing of the crimped threads. After such a washing treatment, the fabric is subjected to a drying and fixing operation on a ream. During this operation, the oar is at a temperature of 150 ° C, the speed of passage of the fabric is 15 meters / minute. Consequently, taking into account this speed of the passage, the rise in temperature of the fabric is limited to approximately 130 ° C. Furthermore, the oar is adjusted so that the fabric is kept in the width obtained after washing, without exerting tension, and also with an introduction supercharging.

At the end of the treatment, a finished fabric is obtained having a width of 145 cm and a weight of 255 grams per square meter.

The density of warp threads is 30.5 threads / centimeter and that of weft 23.8 threads / centimeter.

Such a fabric has an elasticity of the order of 20% both in the warp direction and in the weft direction. This elasticity is determined by measurement on a dynamometer according to the test method defined by French car manufacturers in standard D 41029 under a load of 5daN.

Example 2

Example 1 is repeated except that the warp and weft threads consist of textured polyester threads each consisting of three ends having a titer of 167dtex / 30 strands, the number of warp threads being 4134 threads and the density with the comb also of 26 threads / centimeter.

The weft is also made up of a false twist textured polyester yarn formed by three ends of 167 dtex / 30 strands previously dyed, with a reduction of 14 strokes / centimeter.

When the loom falls, the fabric is 152 centimeters wide and weighs 275 grams / square meter.

Its elasticity in warp and weft is 10%.

A finishing treatment is carried out under the same conditions as in Example 1.

After treatment, a finished fabric is obtained having a width of 142 cm and weighing 335 grams per square meter.

Such a fabric has 28.5 threads / centimeter and 15.5 threads / centimeter.

Like the fabric of Example 1, it has a two-way elasticity of the order of 20%.

This fabric is particularly suitable for coating seats, in particular for cars, and has very good abrasion resistance characteristics.

Claims (2)

1. Process for producing a stretch fabric which can stretch both in the warp direction and in the weft direction and which has coloured effects, able to be used as seat covers, the warp yarns and the weft yarns being synthetic yarns which have received a false-twist texturing treatment making them both bulky and extensible, characterized in that:

   . the textured yarns forming the warp and/or the weft are predyed before the operation of conversion into fabric, this being done under conditions resulting in the shrinkage of the said yarns;

   . the weaving is carried out so that the greige cloth has a warp and weft yarn density of less than 10 to 15% of the final density desired in the finished fabric;

   . the weaving operation is carried out while keeping the warp and weft yarns under tension;

   . after weaving, the greige cloth is subjected to a washing operation, at a temperature below 100°C eliminating any risk of the colouring matter bleeding, then to a finish heat treatment by passage over a stenter, these operations being carried out while keeping the fabric under no tension both lengthwise and widthwise, inducing contraction of the yarn crimp, resulting in the cloth shrinking both in the warp direction and in the weft direction.
2. Process for producing an extensible fabric according to Claim 1, characterized in that:

   . the textured yarn forming the warp and the weft are polyester yarns;

   . during the dyeing operation, the said yarns are in the form of soft packages allowing their shrinkage during this operation, which is carried out in an autoclave at a temperature of around 130°C.