Classifications

• • A—HUMAN NECESSITIES
  • A41—WEARING APPAREL
  • A41D—OUTERWEAR; PROTECTIVE GARMENTS; ACCESSORIES
  • A41D31/00—Materials specially adapted for outerwear
  • A41D31/04—Materials specially adapted for outerwear characterised by special function or use
  • A41D31/08—Heat resistant; Fire retardant
  • A41D31/085—Heat resistant; Fire retardant using layered materials

Definitions

• the present invention relates to the individual protection of individuals and more particularly of workers in the metallurgical industry against projections of materials and in particular of molten metals at high temperature.
• the assembly consists of four superimposed layers, namely, from the inside of the garment to the outside, a smooth fabric acting as lining, foam of rubber or plastic, fabric and metal foil.
• This garment is intended for protection against hot, cold, wind, storm, in particular as sports clothing, for expeditions in cold, hot and windy environments.
• the fabric corresponding to the third layer only serves as a support for the metal sheet and has no particular characteristic.
• This complex material consists, in a known manner, of an assembly of three superimposed layers, the third layer, intended to constitute the interior part of the garment is not very thick and light, the second, intermediate layer, is bulky and of aerated structure and typically the first layer, intended to constitute the outer part of the garment, has a relatively smooth surface condition and comprises at least one fabric, mainly composed of thermostable or flame retardant fibers, having a high coverage factor.
• the first layer has a double role: it protects against the double impact, mechanical and thermal, of the molten metal. This double protection is ensured by the combination of the surface condition (the metal tends to slip on the surface), the composition of the layer (the heat-stable or flame-retardant fibers have good resistance to high temperature rises) and its factor cover (there is no preferential passage of incident radiant heat).
• the second layer acts as a thermal insulator against the heat emitted through the first layer.
• the third layer completes the thermal insulation of the second layer and gives the complex material comfort to wear.
• the relatively smooth surface condition of the first layer can be obtained either by a suitable treatment of the fabric, or by the texture of the latter combined with the fibers which compose it.
• the suitable treatment preferably consists in depositing a thin metallic layer on the outer surface of the fabric: this is for example a specific aluminization technique, already used for the production of protective clothing. But the desired surface finish can be obtained without any special treatment, only thanks to the tight texture of the fabric and the characteristics of the fibers that compose it.
• a flame-retardant cotton fabric the weave of which is a satin, and having a tight texture has a surface condition such that the projections of cast iron, for example, slide and are not caught by the fabric.
• flame retardant cotton is more particularly retained, in pure form, and in intimate mixture of flame retardant cellulosic fibers such as viscose or thermostable fibers such as preoxidized fibers, of polyacrylonitrile type mixed with fibers such as aramids, polyester, wool.
• the high coverage factor means that the first layer is made of a uniformly distributed and homogeneous material, such that it forms a screen without preferential passage.
• This coverage factor is obtained for a fabric by a tight texture, that is to say, for threads of a given size, by a number of threads in warp and weft sufficient for a given thread to be in close contact with the wires adjacent to it.
• This is obtained for a satin weave fabric, twill or derivative, which comprises in warp between 24 and 41 threads per centimeter and in weft between 17 and 26 threads per centimeter, each thread having an apparent diameter comprised between 0,2 and 0 , 6 millimeter.
• the smaller the apparent diameter of the chosen threads the more the tightening of the texture will have to be important to obtain a high coverage factor.
• the second layer should be bulky and have an airy structure.
• the thermal insulation provided by this layer is mainly due to the air contained in the material constituting this layer.
• a sparse product is therefore chosen, having a significant “bulk” (or apparent specific volume), for example a nonwoven, a brushed fleece, a very loose knit.
• the third layer should be thin and light; this will be for example a polyester lining type fabric or a solid nonwoven usable as a lining, for example polyethylene nonwoven known under the name TYVEK.
• the assembly of the three layers constituting the material according to the invention is obtained by any usual assembly means: sewing, bonding ...
• the second and third layers are first assembled by sewing, then the first is assembled layer with the other two thus assembled when making the protective clothing, the seams necessary for the constitution of the clothing being the only connection links between the first layer and the other two.
• the protective clothing using the material according to the invention is sufficiently effective with regard to projections of molten material to be used alone as permanent work clothing without requiring the wearer to put on a superprotection. Its wearing comfort is increased by the fact of its low weight.
• the total weight of the material is at most 750 grams per square meter, and the distribution between the three layers is as follows: 300 to 500 grams per square meter for the first layer, 100 to 400 grams for the second, 20 to 100 grams for the third.
• the complex material for protective clothing consists of the assembly of a flame-retardant cotton fabric, a needled nonwoven based on polyacrylate fibers and a poly fabric. ester type lining.
• the nonwoven fabric which constitutes the intermediate layer weighs 210 grams per square meter and has a thickness of approximately 3 millimeters (according to NF G 07 153).
• the lining fabric which constitutes the layer intended to be in contact with the individual weighs 50 grams per square meter; it is a polyester fabric with a taffeta weave having a texture of 42 x 16, the apparent diameters being 0.14 mm for the warp threads and 0.33 mm for the weft threads.
• the three layers were assembled by sewing, and constitute a complex material weighing 610 grams per square meter. The assembled material has been tested according to the indications of standard NF S74-107.
• molten cast iron (1300 ° C) are poured onto a test tube of the material, inclined at 15 ° to the horizontal plane. Thermal probes are placed in contact with the third layer of the material and make it possible to measure the rise in temperature of this zone due to the impact of the molten metal. In this case, the maximum temperature rise was 22 ° C, which, even in the case of clothing worn directly on the skin, does not cause burns.
• the molten iron has slipped on the surface of the material without any catching, that is to say without drops of cast iron remaining attached to the surface. The same observation was made on the same used material, after it was crumpled and abraded.
• the flame-retardant cotton fabric of Example 1 was previously aluminized, with the deposition according to a particular technique of a thin layer of aluminum weighing 60 grams per square meter. Then the same complex as above was assembled; it therefore weighs 670 grams per square meter.
• the temperature rise observed in the third layer is 13 ° C, lower than that of the first example and therefore giving more favorable protection. Again, no snagging occurred, even in the used state.
• the best performance for the lowest weight was obtained with a complex material weighing 580 grams per square meter. It is composed for the outer layer of an aluminized fabric weighing 300 grams per square meter, consisting of threads based on an intimate mixture of 30% aramid fibers of the "paraaramide” type and 70% of preoxidized polyacrylonitrile fibers; for the intermediate layer of a needled nonwoven of polyacrylate fibers weighing 210 grams per square meter, of thickness 3 millimeters (according to standard NF G 07153); for the inner layer of a perforated polyethylene nonwoven used for the lining, called TYVEK, weighing 40 grams per square meter.
• aluminized materials according to examples 2 and 3 above do not exhibit any attachment even in the used state. This does not mean that the aluminum film deposited on the outside surface of the fabric does not undergo any alteration. But the alterations caused by wear do not cause points of attachment with the cast iron because of the fabric which forms the base of the first layer: the combination of the heat-stable or flame-retardant fibers and the texture promotes the sliding of the cast iron despite the changes in the aluminized coating.
• Example 1 results similar to those of Example 1 were obtained by replacing the intermediate layer either with a brushed fleece knit based on aramid fibers called KERMEL (weighing 350 grams per square meter) or with a relatively loose knit woolen knit weighing 325 grams per square meter.
• Results similar to those of Example 3 were obtained by replacing the first layer with an aluminized fabric of 360 grams per square meter based on fibers called PYROVICEL which are an intimate mixture of flame retardant viscose, preoxidized fibers, polyester and of wool. This fabric is based on a twill weave, 27 x 21 texture, the apparent diameters being 0.43 mm for the warp threads and 0.39 mm for the weft threads.

Landscapes

• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Professional, Industrial, Or Sporting Protective Garments (AREA)
• Manufacture Of Alloys Or Alloy Compounds (AREA)
• Coating By Spraying Or Casting (AREA)
• Laminated Bodies (AREA)
• Details Of Garments (AREA)
• Other Surface Treatments For Metallic Materials (AREA)
• Respiratory Apparatuses And Protective Means (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (3)

Family

ID=9340883

Family Applications (1)

Country Status (6)

Cited By (4)

Families Citing this family (1)

Family Cites Families (3)

• 1986
  • 1986-11-17 FR FR8615961A patent/FR2606601B1/fr not_active Expired - Lifetime
• 1987
  • 1987-11-12 ES ES87402553T patent/ES2022419B3/es not_active Expired - Lifetime
  • 1987-11-12 AT AT87402553T patent/ATE62109T1/de not_active IP Right Cessation
  • 1987-11-12 DE DE8787402553T patent/DE3769109D1/de not_active Expired - Lifetime
  • 1987-11-12 EP EP87402553A patent/EP0272952B1/de not_active Expired - Lifetime
• 1991
  • 1991-04-04 GR GR91400439T patent/GR3001740T3/el unknown

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