EP1098575B2 - Textile complex for making clothes for protection against heat - Google Patents

Abstract

A textile complex is provided including at least a fabric, a textile lap, made of inflammable material, designed to form the external surface of the complex, and a comfort and hygiene lining designed to form the complex internal surface. On the fabric internal surface and/or the lining external surface folds are provided having substantially the same orientation with respect to each other, fixed on the fabric and/or the lining, and defining between the fabric and the lining air-filled passages.

Description

The present invention relates to a textile complex for producing thermal protective clothing. The complex is aimed at providing thermal protection against heat and flame, being used for the realization of clothing for firefighters but also, more generally, in other areas of activity where there is a risk of burns due to heat or fire.

In a fairly old fashion, firefighters use in France a leather jacket equipped with a comfort inner lining in cotton or wool. Such a jacket does not have adequate internal thermal protection. In other countries, jackets used by firefighters are textile-based, either without a waterproof barrier, which leads to a reduction in thermal protection, or with a non-vapor permeable water barrier. water, which prevents the evaporation of perspiration and increases the problem of heat stress. Thermal stress is a physiological phenomenon resulting from the elevation of the internal temperature of the body, occurring under the effect of external factors such as a warm atmosphere, or under the effect of a large and prolonged effort. Thermal stress results in an increase in the internal temperature of the body that can no longer thermoregulate, which can lead to discomfort, or even a syncope or a cardiac event. It is known today that when the body temperature exceeds + 1.5 ° C the normal temperature, the judgment and reaction are altered to the point of causing accidents in dangerous environments. The latest study of firefighter fatalities in the USA reports only 8% of burn deaths, 42% of deaths are directly due to heat stress, and the remaining 50% are accidents with no apparent cause but specialists are moving closer together. stupid accidents related to impaired judgment related to heat stress.

There is a European directive on personal protective equipment used in particular by firefighters. A jacket must have a number of criteria, including protection against radiant heat, protection against convective heat, have a good thermal stability of the constituent materials, meet criteria of pure fireproofness, and have good impermeability.

A textile complex for producing such equipment is known from US-A-5,274,849, which represents the preamble of claim 1.

In addition, a jacket must allow an operator to protect it in extreme conditions of an accidental nature, including by providing a time of escape. In particular, it is necessary to protect a firefighter against a phenomenon of "flash-over". Flash-over is a very fast transition stage in the development of a city fire and occurs when gases and vapors in a room reach a temperature of 500 to 600 ° C and ignite suddenly. In a fraction of a second, the temperature rises from 500 to 1000 ° C, corresponding to an incident heat flux of the order of 40 kW / m ² . An operator should be allowed to resist this sudden increase in temperature long enough to be able to move away from home.

It is known to create a textile complex to achieve these objectives. Such a textile complex comprises an outer protective fabric made of a non-flammable material, for example based on aramid fiber, meta-aramid or polyamide imide. This fabric incorporates thermal protection qualities, provides mechanical resistance to abrasion and tear, and has been water-repellent to water-repellent and chemical-liquid-repellent in general. Behind this protective fabric is a waterproof and breathable membrane, generally fixed on a textile surface ensuring its mechanical strength, allowing to let the water vapor resulting for example from the perspiration of a user, but not the water under its liquid form. In addition, this membrane provides a windproof effect, which contributes to the thermal insulation of the jacket by slowing the penetration of heat flows. Under the membrane is disposed a thermal insulation consisting of a three-dimensional mesh knit, as described in document EP 0443991, or by a felt capable of trapping air, as described in document EP 0 364 370. This thermal insulation is usually sewn on a liner.

Such a jacket has the advantage of providing excellent thermal protection under an extremely high heat flow of 40 kW / m ² , a very important efficiency, even too important because of its high insulating power it does not allow to the user to be sensitive to heat to heat flows of 0 to 1 kW / m ^2, corresponding to the usual working conditions of firefighters, and to detect a possible danger. Under these conditions, the overprotected operator may have to take unmeasured risks due to an alteration of the perception of the heat flow. Such a jacket is also uncomfortable insofar as it is thick and heavy, and where it is loaded with water, especially at the level of the thermal insulating material, which can be translated, in case of sudden rise in temperature, by a vaporization of this water likely to burn the operator.

In addition, when the jacket is wet, following a wet intervention or washing, the felt or knit mesh absorbs a lot of water, resulting in a significant drying time during which the jacket is wet. is not usable.

Figures 1 and 2 show two graphs that illustrate the behavior of different complex designed to make clothing for firefighters, taking into account the European standard EN 469.

FIG. 1 illustrates the evolution of the heat transfer factor TF%, which is the ratio of the heat flux that has passed through the product to the incident heat flux Q _o . The incident heat flux is the heat flux generated by a thermal source to which the sample is exposed.

Figure 2 illustrates the evolution of the warning time T. ₁₂ as a function of the incident heat flux Q _o . The warning time is the time after which the user painfully feels the heat. It is sought to obtain a T. ₁₂ of about 15 seconds for an incident flux of 40 kW / m ² .

1. A = cuir
2. B = cuir + doublure coton
3. C = cuir + doublure laine
4. D = tissu + membrane + non tissé 90 g/m² + doublure 120 g/m²
5. E = tissu + membrane + maille 220 g/m² + doublure 120 g/m²
6. F = tissu + membrane + feutre 120 g/m² + doublure 120 g/m²

The different curves represented in FIGS. 1 and 2 were obtained by carrying out measurements on the following products or complexes, according to the method of standard EN 366 as described in its draft revision CEN / TC162 / WG2 / N266 of 27/01/97:

1. A = leather
2. B = leather + cotton lining
3. C = leather + wool lining
4. D = + membrane + fabric Nonwoven 90 g / m ² + liner 120 g / m ²
5. E = fabric + membrane + mesh 220 g / m ² + lining 120 g / m ²
6. F = fabric + membrane + felt 120 g / m ² + lining 120 g / m ²

• Tissu : tissu référence 4781 de la société DMC Tissus Techniques, Sergé 2/1, 195 g/m², en Nomex℘ Delta TA de Dupont de Nemours, mélange de 75 % de fibres meta aramide, 23 % de fibres para aramide et 2 % de fibres antistatiques.
• Membrane : Référence 89/55 de la société Proline, membrane microporeuse imperméable et respirante en Polyuréthanne ignifuge d'environ 40 g/m², contrecollée sur un non tissé Sontara℘ Nomex℘ SL Type E-89, mélange de meta et para aramide d'environ 90 g/m².
• Doublure : tissu réf 4948 de la société DMC Tissus Techniques, Toile, 120 g/m², en Nomex℘/Viscose FR, mélange de 50 % de fibres meta aramide et de 50 % de fibres viscose Ignifugée dans la masse.
• Non tissé : Sontara℘ Nomex℘ SL Type E-89, mélange de meta et para aramide d'environ 90 g/m².
• Maille : maille tridimensionnelle référence AR220 de la société TTI, 220 g/m², en Nomex℘ T450, 100 % meta aramide.
• Feutre : feutre aiguilleté de la société DUFLOT, 120 g/m², en Nomex℘, en 100 % aramide.

As examples, the products used are as follows:

• Fabric: fabric reference 4781 from DMC Tissus Techniques, Twill 2/1, 195 g / m ² , in Nomex® Delta TA from Dupont de Nemours, blend of 75% aramid meta fibers, 23% aramid fibers and 2 % of antistatic fibers.
• Membrane: Reference 89/55 of the company Proline, waterproof and breathable microporous membrane in flame retardant Polyurethane of about 40 g / m ² , laminated on a non woven Sontara® Nomex® SL Type E-89, mixture of meta and para aramid about 90 g / m ² .
• Lining: fabric ref 4948 from DMC Fabrics Techniques, Canvas, 120 g / m ² , in Nomex® / Viscose FR, blend of 50% meta-aramid fibers and 50% viscose fibers Fireproof in the mass.
• Nonwoven: Sontara℘ Nomex℘ SL Type E-89, mixture of meta and para aramid of about 90 g / m ² .
• Mesh: three-dimensional mesh reference AR220 of the company TTI, 220 g / m ² , Nomex℘ T450, 100% meta aramid.
• Felt: needle felt from DUFLOT company, 120 g / m ² , in Nomex®, in 100% aramid.

These different curves perfectly summarize the advantages and disadvantages of the various jackets known that have been presented above.

The object of the invention is to provide a textile complex for clothing production, which is light and comfortable, which, under usual conditions of intervention (flow of 0 to 1 kW / m ² approximately), transmits the heat relatively well ( which corresponds to a high TF%) and quickly alerts the operator of the presence of a hazard (which corresponds to a low T. ₁₂ ), and which, in critical conditions, such as a resulting heat flow a flash-over phenomenon (flow of the order of 40 kW / m ² ), ensures for a sufficient period of time and in compliance with the standards, a high insulation rate (ie a low TF%), to ensure the operator a reasonable time of escape. In addition, this complex must allow rapid drying when wet.

For this purpose, the textile complex it concerns, of the type comprising at least one fabric or a textile web, made of a non-flammable material, intended to form the outer face of the complex and a comfort and cleanliness lining intended to form the inner face of the complex, is characterized in that on the inner face of the fabric and / or on the outer face of the lining are disposed beads of textile material having substantially the same orientation, fixed by bonding to the fabric and / or on the lining during its manufacture, to be an integral part, and delimiting between the fabric and the lining of the channels filled with air.

The beads delimit with the lining, on the one hand, and the wall of the complex vis-à-vis the lining, on the other hand, channels that are filled with air. This air is not static but can circulate, insofar as it is not trapped, by a tight mesh, as is the case for example with structures of knit type three-dimensional mesh or net. Thus, under normal conditions of use (0 to 1 kW / m ² of heat flow), there is no retention of water in these channels, or significant overheating of the air. Conversely, during a very sudden increase in temperature (about 40 kW / m ² of heat flow for example), the amount of air in the channels defined by the beads constitutes a sufficient thermal insulation, and meets the standard EN 469, to allow the operator to move away from the dangerous place.

This simplicity of structure contributes to the lightness of the garment obtained, and consequently to its comfort. This is recessed by the circulation of air in the channels, which promotes the evaporation of the sweat water absorbed by the lining. Indeed, it is known that to help the thermoregulation of the body, it is absolutely essential to allow evaporation of the water of sweating. When body temperature rises, the mechanism of perspiration intervenes to cool the body by evaporation of sweat. If the sweat water can not evaporate and accumulates in liquid form in the different textile layers, the thermoregulatory mechanism of sweating is neutralized and the body temperature continues to rise. These characteristics, of a on the other hand, improve the thermoregulation of the body of the operator and reduce heat stress and, secondly, facilitate the drying of the garment when it has been wet, during an intervention, or for its maintenance. In fact, because of its very small structure, the water absorption and storage capacities of the invention are practically reduced to those of the lining supporting the beads, compared with those of a felt that acts as a sponge. The main disadvantage of the current complexes, such as felts or three-dimensional mesh knits, is precisely their low propensity to allow the evaporation of perspiration. On the contrary, they tend to absorb it and store it.

Advantageously, the beads are made of a material that is not very compressible under the effect of an increase in heat.

This makes it possible to maintain a sufficient volume of insulating air to ensure protection, including under the effect of large heat flows (about 40 kW / m ² for example).

According to a first embodiment of this complex, each bead is made from thermostable fibers, such as para-aramid.

Advantageously in this case each bead is constituted by a bundle of son assembled to each other, for example two Nm 8/2 twists twisted together. Such a structure is less compressible than an equivalent title wire composed of a single end.

According to one possibility, always in the case of this type of bead, each bead is attached to the liner by bonding with the son of this liner, during the manufacture thereof.

In order to ensure the formation of a sufficient volume of air between the beads, the thickness of each bead is greater than 0.3 mm, and preferably between 1 and 10 mm, and the spacing of the beads is greater at 2 mm, and preferably between 2 and 15 mm.

In order to promote the circulation of air, in the case of a garment made from a textile complex, such as that which has just been defined, the beads and the channels they delimit have a longitudinal general orientation to the garment, and especially vertical in the case of a jacket, promoting air circulation by a natural phenomenon of convection.

It is possible to provide between the outer protective fabric and the lining a waterproof and breathable membrane allowing water vapor to pass but not water in liquid form, this membrane also having a windproof effect, favorable to the protection thermal.

• Figure 1 représente une série de courbes montrant l'évolution du facteur de transmission de chaleur TF % en fonction du flux de chaleur incident ϕ_o ;
• Figure 2 représente une série de courbes montrant l'évolution du temps d'alerte T12 en fonction du flux de chaleur incident ϕ_o ;
• Figure 3 est une vue en perspective éclatée des différentes couches constitutives du complexe ;
• Figure 4 est une vue en coupe de ce complexe, transversalement aux bourrelets que comporte celui-ci ;
• Figure 5 est une vue en perspective partiellement arrachée d'une partie de veste réalisée à partir du complexe de figures 1 et 2.

In any case, the invention will be better understood from the description which follows, with reference to the appended diagrammatic drawings showing, by way of nonlimiting examples, an embodiment of this textile complex and a form of execution. of a jacket obtained using this complex:

• FIG. 1 represents a series of curves showing the evolution of the heat transfer factor TF% as a function of the incident heat flux φ _o ;
• FIG. 2 represents a series of curves showing the evolution of the warning time T12 as a function of the incident heat flux φ _o ;
• Figure 3 is an exploded perspective view of the various constituent layers of the complex;
• Figure 4 is a sectional view of this complex, transversely to the beads that comprises it;
• Figure 5 is a partially cutaway perspective view of a jacket portion made from the complex of Figures 1 and 2.

The complex represented in the drawing comprises an outer protective fabric 2 made of a non-flammable material, consisting of a fabric reference 4781 from DMC Tissus Techniques, Twill 2/1, 195 g / m ² , in Nomex® Delta TA from Dupont de Nemours, blend of 75% meta aramid fibers, 23% aramid fibers and 2% antistatic fibers. Against this outer fabric is arranged a waterproof and breathable membrane, consisting of the reference 89/55 of the company Proline, waterproof and breathable microporous membrane in flame retardant polyurethane of about 40 g / m ² , laminated on a nonwoven Sontara℘ Nomex℘ SL Type E-89, mixture of meta and para aramid of about 90 g / m ² .

The complex finally comprises a liner 4 consisting for example of a fabric reference 4948 from DMC Tissus Techniques, Canvas 120 g / m ² , made of Nomex® / Viscose FR, a blend of 50% of meta-aramid fibers and 50% of fibers. viscose flame retardant in the mass.

On the liner 4 is fixed, on the side facing the membrane 3, a series of continuous parallel beads 5 representing a mass per unit area of 70/80 g / m ² , in this case consisting of 100% Nm aramid fiber yarn. 8/2/2 (doubling of 2 ends of Nm 8/2). Insofar as the lining is constituted by a fabric, the connection of the beads with the fabric is obtained during weaving, by a particular evolution of certain background threads of said fabric.

It should be noted that in the complex shown in Figures 3 to 5, the layers 2, 3 and 4 are generally not assembled, but simply juxtaposed. However it is quite possible that some of these layers are assembled by gluing for example, in the case of specific needs.

The thickness of each bead is of the order of 1 mm, and the spacing of the beads is of the order of 10 mm.

FIG. 5 represents a jacket 6 made from the textile complex which has just been defined, and in which the beads 5 are oriented vertically.

The curves of FIGS. 1 and 2 illustrate the behavior of a complex I according to the invention.

This complex has the advantage, compared to some existing complexes, to be lighter and more flexible, the beads 5 advantageously replacing a felt for trapping air. These beads are lighter and more flexible than such a felt or knit three-dimensional mesh.

The water absorption capacity of these beads is very small compared to such a felt or a three-dimensional mesh, which greatly limits the phenomenon of pumping and storage of sweat water in the garment.

Thus, the pumping and water storage capacities of the insulating complex of the invention are practically reduced to those of the lining used as support for the beads, which in its embodiment as described above represents 2.5 times its weight. dry. In comparison that of the complex F using a felt, which acts as a sponge, is 10 times its dry weight.

Maintained at a distance from the membrane by the beads, the lining serving as a support for the complex of the invention is converted into an exchange surface of the sweat water (which it absorbs) with the air circulating in the formed channels. by these so-called beads, accelerating evaporation and allowing the body to thermoregulate much more quickly. The onset of heat stress is delayed or suppressed, especially under the usual working conditions of 0-1 kW / m ² .

This low water absorption capacity of the complex according to the invention also has the advantage of limiting the risk of burning by vaporization of the water trapped in the jacket in the event of exposure to a sudden heat flow.

It also avoids the weight gain of the garment in operation, aggravating factor of heat stress. Indeed, recent physiological studies have shown that the weight of the textile intervention jackets of firefighters had a direct influence on the heat stress generated.

In terms of protection, the volume of air maintained in the channels ensures a satisfactory thermal insulation by limiting a rapid transmission of heat under critical conditions (flow of the order of 40 kW / m ² ). The structure of this complex also ensures good sensitivity to heat under normal conditions of use, and therefore a low warning time T. ₁₂ , due to its low surface area, as shown in FIG. Warning in normal conditions is similar to that of leather + lining complexes, recognized as being more reassuring than that of traditional textiles too insulating (curves E and F).

It can be seen from FIG. 1 that, in terms of thermal conduction and non-confinement of heat, the complex according to the invention provides a good comfort at low energy, 0 to 1 kW / m ² (usual working conditions) comparable to that of leather + lining complexes recognized as posing few problems of heat stress, which results in a relatively high TF% (good heat transfer). On the contrary, it has high incident heat fluxes (about 40 kW / m ² ), a TF% heat transmission factor, low (good insulation), comparable to that of much heavier complexes, less comfortable and retaining much more the water.

The comfort of this complex in terms of heat stress reduction, is also expressed by a particularly low Ret (evaporative resistance) compared to existing products on the market.

The more the complex of the jacket will allow a good evaporation of sweat, which means that it will have a low resistance to evaporation, the better the body can thermoregulate and avoid the accident.

• C : 85.0 m².Pa/W
• D : 26.7
• E : 28.5
• F : 31.0
• I : 25.6

The table below gives the Ret of the different complexes of fig 1 (measured according to standard EN31092)

• C: 85.0 m ² .Pa / W
• D: 26.7
• E: 28.5
• F: 31.0
• I: 25.6

This classification evolves in parallel with T. ₁₂ which illustrates the thermal sensitivity of the complex. There is therefore the double advantage in terms of comfort of combining low thermal insulation (low heat storage) in normal conditions and good evaporation, hence significant progress in terms of reducing the risk of heat stress.

It goes without saying that the invention is not limited to the sole embodiment of this textile complex or its sole application to the realization of a jacket, it encompasses all variants. It is thus in particular that the lining could be associated with a membrane or a film, that the beads could be discontinuous and / or could be made of another material, such as silicone, or that the complex could be constituted by two unbonded layers, such as trousers and overpants on the inner side of which are arranged beads, without departing from the scope of the invention.

Claims (10)

1. A textile composite for the production of garments providing thermal protection, of the type comprising at least one fabric (2), or textile web, made of a non-flammable material and intended to form the outer face of the composite, and a comfort and hygiene lining (4), intended to form the inner face of the composite, there being disposed on the outer face of the lining (4) beads (5) oriented in substantially the same direction and bonded onto the lining and defining between the fabric and the lining channels filled with air, said beads being of textile material, characterised in that said beads are fixed to the lining at the time of weaving thereof by means of threads of said lining, to make them an integral part thereof.
2. A textile composite according to claim 1, characterised in that the beads (5) are continuous.
3. A textile composite according the claim 1, characterised in that the beads (5) are discontinuons.
4. A composite according to one of claims 1 to 3, characterised in that the lining (4) comprises, on its face directed towards the outside of the composite, beads (5) oriented in substantially the same direction and defining, with the opposing wall of the composite, channels filled with air.
5. A composite according to any one of claims 1 to 4, characterised in that the beads (5) are made of a material which is not readily compressible under the effect of increased heat.
6. A composite according to claim 5, characterised in that each bead (5) is made of thermostable fibres such as para-aramid.
7. A composite according to any one of claims 1 to 6, characterised in that each bead (5) consists of a bundle of threads combined together, such as two Nm 8/2 twists twisted together.
8. A composite according to any one of claims 1 to 7, characterised in that the thickness of each bead (5) is greater than 0.3 min. and preferably between 1 and 10 mm.
9. A composite according to any one of claims 1 to 8, characterised in that the spacing of the beads (5) is greater than 2 mm, and preferably between 2 and 15 mm.
10. A garment made from a textile composite according to one of claims 3 to 9, characterised in that the beads (5) and the channels which they define exhibit a longitudinal general orientation relative to the garment, and in particular vertical in the case of a jacket.

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