EP1179622B1 - Process for manufacturing a reinforcing yarn - Google Patents

Abstract

The object of the invention is a method of manufacturing, by friction spinning, a reinforcing thread (1) for fabric covering or a technical textile intended to be incorporated in a textile base, in which: the spinning machine (7) is supplied with a core thread (2); the spinning machine (7) is supplied simultaneously with a sliver (9) of fibers (3, 4), the said fibers (3, 4) being individualized and then associated with the said core thread (2); in which the sliver (9) of fibers is formed from a mixture of hot-melt fibers (3) and high melting point fibers (4).

Description

The invention relates to a method of manufacturing a friction wire by friction spinning. reinforcement for interlining or technical textiles.

Such threads are intended to be woven or to be incorporated into a textile base for example formed of a knitted fabric.

They are frequently used in articles intended for stabilization of the type tailor cloths or breastplates. They bring to the products in which they are incorporated their nervousness and resistance.

We already know, replacing natural hair, the use of threads synthetic monofilaments as reinforcement threads.

One of the problems that arises is the appearance, especially during washing successive, of a slip of these threads inside the base texture textile in which they are incorporated.

Document EP-A-0 428 430 describes a reinforcing thread comprising a core thread and coating fibers which are bonded around the core wire using a adhesive substance. The coating fibers then give relief to the wire, which allows it to hang in the texture and therefore prevents it from sliding.

This technique has the disadvantage of providing, beforehand or after the combination of the coating fibers on the core wire, a step specific deposit of an adhesive substance.

In addition, the association of a second type of coating fibers is made necessary to improve the feel of the reinforcement wire.

The invention therefore aims to remedy these drawbacks by proposing a method manufacturing a reinforcing thread which plans to use the spinning method friction to associate, in a single step, coating fibers to a core wire, said fibers which can then be bonded to the core wire by heating and the wire thus obtained having a satisfactory feel.

• on alimente la machine à filer avec un fil d'âme ;
• on alimente simultanément la machine à filer avec une mèche de fibres, lesdites fibres étant individualisées puis associées audit fil d'âme ;

dans lequel la mèche de fibres est formée d'un mélange de fibres thermofusibles et de fibres à haut point de fusion.To this end, the invention provides a method of manufacturing by friction spinning a reinforcing thread for interlining or technical textile intended to be incorporated into a textile base, in which:

• the spinning machine is fed with a core thread;
• the spinning machine is simultaneously fed with a wick of fibers, said fibers being individualized and then associated with said core thread;

wherein the wick of fibers is formed from a mixture of hot melt fibers and high melting point fibers.

The individualization and association of fibers on the core thread can be made with perforated spinning drums with strong air intake (friction spinning process).

The core thread is formed from a monofilament thread or a multifilament thread.

According to one embodiment, the core wire further comprises a wire formed of fibers which is associated or juxtaposed with said monofilament yarn or multifilament.

A step of heating the reinforcing wire to a temperature between the melting temperature of hot melt fibers and that of high point fibers may be expected.

• la figure 1 représente, de façon schématique, une machine à filer à friction qui est alimentée d'une part avec un fil d'âme et d'autre part avec une mèche de fibres formée d'un mélange de fibres thermofusibles et de fibres à haut point de fusion ; ladite machine comprenant des tambours de filature perforés pour individualiser et associer lesdites fibres sur le fil d'âme ;
• la figure 2 représente, en vue de face, un fil de renfort obtenu par mise en oeuvre du procédé suivant l'invention, ledit fil comprenant un fil d'âme formé d'un fil monofilament et des fibres d'enrobage associées à lui ;
• la figure 3 est une vue en coupe du fil représenté sur la figure 2 ;
• la figure 4 représente, en coupe, un fil de renfort obtenu par mise en oeuvre du procédé suivant un deuxième mode de réalisation de l'invention, ledit fil comprenant un fil d'âme formé d'un fil monofilament et d'un fil fibres, et des fibres d'enrobage associées à lui.

Other objects and advantages of the invention will appear during the description which follows, given with reference to the appended drawings, in which:

• Figure 1 shows, schematically, a friction spinning machine which is fed on the one hand with a core thread and on the other hand with a wick of fibers formed from a mixture of hot-melt fibers and fibers to high melting point; said machine comprising perforated spinning drums for individualizing and associating said fibers on the core thread;
• FIG. 2 represents, in front view, a reinforcing thread obtained by implementing the method according to the invention, said thread comprising a core thread formed by a monofilament thread and coating fibers associated with it;
• Figure 3 is a sectional view of the wire shown in Figure 2;
• FIG. 4 represents, in section, a reinforcing thread obtained by implementing the method according to a second embodiment of the invention, said thread comprising a core thread formed by a monofilament thread and a fiber thread , and coating fibers associated therewith.

The reinforcing wire 1 comprises a core wire 2 and coating fibers 3, 4 deposited around said core wire 2 by a friction spinning technique.

For example, when the textile base is a fabric, the reinforcing thread 1 is woven and when the textile base is a knitted fabric, the reinforcing threads 1 are incorporated into the mesh system without participating in the formation thereof. According to destination of the textile base, they can be introduced in the weft direction and / or in the chain direction.

According to an embodiment shown in Figures 2 and 3, the core wire 2 is formed of a thread 5 which is generally monofilament but which can also be multifilament.

The core wire 2 is made of a synthetic or artificial material such as for example polyamide, polyester or viscose.

In another embodiment shown in FIG. 4, the core wire 2 further includes a wire 6 formed of staple fibers. The two wires 5, 6 are for example juxtaposed parallel to each other. Alternatively, they can be associated, for example by winding or wrapping the wire 6 formed of fibers discontinuous on the wire 5. The association or the juxtaposition is carried out prior to feeding the spinning machine 7 with the core thread 2.

The function of the wire 6 formed of staple fibers is to promote the attachment coating fibers 3, 4 on the core wire 2. The material forming the fibers of the wire 6 may be the same or different from that forming the wire 5.

The choice of the type of core wire 2 used depends on the applications targeted for the reinforcing wire 1. The core wire 2 is in particular a wire of large titration, by example between 160 Dtex and 800 Dtex.

According to the invention, the coating fibers 3, 4 are formed from a mixture of hot-melt fibers 3 and fibers 4 with high melting point.

The term "high melting point fibers" is used to denote fibers which melt or degrade at a temperature above the temperature of fusion of hot-melt fibers 3.

For example, the hot-melt fibers 3 have a melting point below 150 ° C, the melting point of fibers 4 with a high melting point being greater than 180 ° C.

The hot-melt fibers 3 can be formed from copolymers, for example based on copolyamides, copolyesters. 4 high-melting fibers can be synthetic, for example formed from polyamide, polyester, or artificial, for example made of viscose or natural, for example made of cotton.

According to another embodiment, the hot-melt fibers 3 are fibers two-component, for example of the CoPA / PA-6 type with a melting point included between 135 ° C and 145 ° C.

The hot-melt fibers 3 and the fibers 4 with high melting point have generally a titration, identical or different, between 1 Dtex and 3.5 Dtex.

The hot-melt fibers 3 and the fibers 4 with high melting point are arranged simultaneously on the core thread 2 by means of a friction spinning machine 7. The friction spinning technique is itself known, but we continue below, in relation to FIG. 1, its essential characteristics for the understanding of the invention.

A coil 8 on which the core wire 2 has been wound is provided to be able to feeding, along a first path, the spinning machine 7 with said core wire 2.

Following a second path, a wick 9 or ribbon which is formed of mixture of hot melt fibers 3 and high melting point fibers 4 is fed into the spinning machine 7 via rollers 10. In the embodiment shown in Figure 1, the spinning machine 7 is powered with four identical wicks 9.

The wick 9 is prepared in a conventional manner by working, carding and drawing the fibers 3, 4 making it up. Hot melt fibers 3 and the fibers 4 with high melting point are then distributed uniformly in the wick 9 so that they are arranged statistically on the core wire 2.

The spinning machine 7 has perforated spinning drums 11 in which the two paths meet so as to be fed simultaneously in core wire 2 and in coating fibers 3, 4.

The function of the drums 11 is, by their rotation, to individualize the fibers 3, 4 forming the wick 9 and placing said fibers 3, 4 individualized on the core 2.

The term "individualized" is used here to describe the condition of fibers 3, 4 by as opposed to fibers which have been twisted and constitute a thread or still as opposed to long filaments.

At the outlet of the drums 11, the reinforcing wire 1 formed from the core wire 2 on which the hot melt fibers 3 and fibers 4 with high melting point are arranged, is wound on a reel 12.

In a first alternative embodiment, the reinforcing wire 1 is then heated at a temperature between the melting temperature of the fibers 3 and that of fibers 4 with high melting point.

This step allows, by fusion of the hot-melt fibers 3, to ensure a bonding fibers 4 with a high melting point on the core wire 2.

Furthermore, by an appropriate choice of the mixture of materials forming the coating fibers 3, 4, the feel of the reinforcing wire 1 can be made satisfactory in view of its application.

Indeed, and unlike the wire described in document EP-A-0 428 430, the coating fibers 3, 4 are already formed of two materials of nature different.

In a second alternative embodiment, the reinforcing wire 1 is first incorporated into the textile base by weaving or knitting techniques then the textile base is heated to a temperature between melting temperature of hot-melt fibers 3 and that of fibers 4 at high melting point so as to ensure bonding of fibers 4 with high melting point on the core 2.

This variant is made possible by the fact that, before all heating, the coating fibers 3, 4 have characteristics of adhesion on the core wire 2 which are sufficient to allow the work of the wire reinforcement 1.

The coating fibers 3, 4 have the function of giving relief to the reinforcing wire 1 which allows it to be hooked in the texture.

For this purpose, they must be integral with the core wire 2 to avoid any slippage reinforcement wire 1 in the texture, especially during successive washes of the textile base.

The reinforcing wires 1 have a diameter generally greater than ten hundredths of millimeter and the core wire can have great rigidity.

In a preferred embodiment, the proportion of hot-melt fibers 3 in the wick 9 is between 20% and 60% by weight.

Indeed, it turns out that 20% of hot-melt fibers 3 in the wick 9 provides sufficient cohesion of the coating fibers 3, 4 on the core wire 2 to meet the average specifications required.

However, depending on the performance essential for resistance to maintenance treatments (washing, dry cleaning), it is better to increase the percentage of hot-melt fibers 3 in the wick 9.

However, it turns out that more than 60% of hot-melt fibers 3 in the wick 9 does not allow the implementation of the process under good conditions.

Indeed, the preparation of the coating fibers 3, 4 to present them parallel, in the form of wick 9, the continuous spinning is then made practically impossible. This problem is partly due to the lack of crimps permanent on the coating fibers 3, 4 and the excessive flexibility of the hot melt fibers 3.

An exemplary embodiment of a reinforcing wire 1 is given below the invention, given by way of illustration and not limitation.

• d'un fil monofilament 5 en Polyamide 6-6 - 22/100 (430 Dtex) ; et
• d'un fil 6 formé de fibres discontinues en viscose de 1,7 Dtex coupe 40 mm, le titrage du fil étant de 250 Dtex.

The core wire 2 is formed:

• a monofilament 5 thread of Polyamide 6-6 - 22/100 (430 Dtex); and
• of a thread 6 formed of viscose staple fibers of 1.7 Dtex cuts 40 mm, the titration of the thread being 250 Dtex.

• 40 % de fibres 3 en copolyamides thermofusibles de 2,2 Dtex coupe 43 mm;
• 60 % de fibre 4 de viscose de 1,7 Dtex coupe 38 mm.

The coating fibers 3, 4 are formed from a mixture of:

• 40% of fibers 3 in hot-melt copolyamides of 2.2 Dtex cut 43 mm;
• 60% viscose fiber 4 of 1.7 Dtex cuts 38 mm.

Reinforcement wire 1 thus obtained with a titration of 970 Dtex including 44% of wire monofilament 5, 26% yarn 6 formed of staple fibers and 30% of fibers coating 3, 4.

Claims (15)

1. A method of manufacture by friction spinning of a reinforcing yarn (1) for an interfacing or technical textile intended to be incorporated in a textile base, in which:

   the spinning machine (7) is supplied with a core thread (2) ;

   the spinning machine (7) is simultaneously supplied with a roving (9) of fibres (3, 4), said fibres (3, 4) being individualised and then associated with said core thread (2);

   said method being characterised in that the roving (9) of fibres is formed from a mixture of hot-melt fibres (3) and high melting point fibres (4).
2. A method according to Claim 1, characterised in that the individualisation and association of the fibres (3, 4) on the core thread (2) are implemented by means of perforated spinning drums (11) with strong air suction.
3. A method according to Claim 1 or 2, characterised in that the proportion of hot-melt fibres (3) in the roving (9) is between 20% and 60% by weight.
4. A method according to any one of Claims 1 to 3, characterised in that the hot-melt fibres (3) are formed from copolymers, for example based on copolyamides or copolyesters.
5. A method according to any one of Claims 1 to 3, characterised in that the hot-melt fibres (3) are bicomponent fibres.
6. A method according to any one of Claims 1 to 5, characterised in that the hot-melt fibres (3) have a melting point below 150°C, the melting point of the high melting point fibres (4) being above 180°C.
7. A method according to any one of Claims 1 to 6, characterised in that the high melting point fibres (4) are synthetic, for example formed from polyamide or polyester.
8. A method according to any one of Claims 1 to 6, characterised in that the high melting point fibres (4) are artificial, for example formed from viscose.
9. A method according to any one of Claims 1 to 6, characterised in that the high melting point fibres (4) are natural, for example formed from cotton.
10. A method according to any one of Claims 1 to 9, characterised in that the core thread (2) is formed from a monofilament thread (5).
11. A method according to any one of Claims 1 to 9, characterised in that the core thread (2) is formed from a multifilament thread (5).
12. A method according to Claim 10 or 11, characterised in that the core thread (2) also comprises a thread (6) formed from discontinuous fibres which is associated or juxtaposed with said monofilament or multifilament thread (5).
13. A method according to any one of Claims 1 to 12, characterised in that the core thread (2) is synthetic, for example formed from polyamide or polyester.
14. A method according to any one of Claims 1 to 12, characterised in that the core thread (2) is artificial, for example formed from viscose.
15. A method according to any one of Claims 1 to 14, characterised in that it comprises a step of heating the reinforcing yarn (1) to a temperature between the melting temperature of the hot-melt fibres (3) and that of the high melting point fibres (4).

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