Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F41—WEAPONS
  • F41H—ARMOUR; ARMOURED TURRETS; ARMOURED OR ARMED VEHICLES; MEANS OF ATTACK OR DEFENCE, e.g. CAMOUFLAGE, IN GENERAL
  • F41H1/00—Personal protection gear
  • F41H1/02—Armoured or projectile- or missile-resistant garments; Composite protection fabrics
• • 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
  • A41D31/26—Electrically protective, e.g. preventing static electricity or electric shock

Definitions

• the present invention relates to a fabric that is suitable for making protective clothes against electroshock weapons.
• a well-known type of electroshock weapon is the Taser ® , which causes paralysis by delivering an electric shock of 50,000 to 1,000,000 volt.
• a taser generally has two pins (electrodes), with a current passing through them.
• the pins can penetrate through clothes and may be fitted with barbs to prevent them from becoming detached easily.
• the pins When the pins come sufficiently close to the human body, the person in question receives a number of electric shocks. These block the electric signals between the brain and the muscles, causing paralysis and collapsing of the person in question.
• the pins (electrodes) are connected to the device by electrically conducting wires, so they can be propelled from the weapon over a distance of 4-10 metres.
• Fabrics for making such protective clothes are already known per se. It is for example known to weave into a fabric electrically conducting wires at a certain distance (1 cm) from one another.
• these fabrics have the disadvantage that sparks are generated when an electroshock weapon comes into contact with them but the electrodes of the weapon do not come into direct contact with the wires present. Furthermore, these fabrics cannot neutralize the whole current surge issuing from the electroshock weapon.
• US patent specification 2006/0,175,581 discloses a fabric that is provided with an electrically conducting coating.
• this solution has the disadvantage that an additional processing step is required in order to apply the coating to the fabric.
• the effect of the coating is limited in time, because it disappears from the fabric after a number of washing operations.
• a coated fabric is also inevitably much less comfortable to wear, because it is much less permeable to air and water vapour.
• the aim of the present invention is therefore to provide a fabric for making protective clothes against electroshock weapons that are comfortable to wear and offer permanent protection against electroshock weapons.
• the aim of the invention is achieved by providing a fabric that is suitable for making protective clothes against electroshock weapons, which comprises electrically conducting elements, the electrically conducting elements being formed either by stainless-steel fibres or by mutually perpendicular stainless-steel filaments, and the said fabric having an electrical resistance of at most 10 5 ohm/square, measured according to European Standard EN 1149.
• the electrical resistance of the fabric is measured more specifically according to European Standard EN 1149-1.
• the fabric preferably has an electrical resistance that lies between 10 2 and 10 5 ohm/square (O/square), measured according to European Standard EN 1149-1, and more preferably one that lies between 10 3 and 10 4 ohm/square.
• the fabric according to the invention has an electrical resistance of at most 10 4 ohm/square, measured according to European Standard EN 1149-1. Most especially, the fabric according to the invention has an electrical resistance of at most 10 3 ohm/square, measured according to European Standard EN 1149-1.
• This European Standard EN 1149-1 is used to determine in particular the surface resistance of a fabric with the aid of two metal rings of a different diameter and is carried out at a humidity of 25% and a temperature of 23°C (it should be mentioned here that this very low humidity should be regarded as a worst case scenario).
• the presence of sufficient stainless-steel fibres or stainless-steel filaments in the fabric ensures that the fabric has a much higher conductivity than the human body, so the electric charge issuing from the electroshock weapon is dissipated through the fabric, and the risk of injury is minimized for the person wearing the protective clothes made from such a fabric.
• the use of stainless steel has the advantage that the fabric is washable and offers permanent protection from electric discharges issuing from electroshock weapons. Another advantage is that stainless steel does not corrode.
• the said stainless-steel fibres are (intimately) mixed with the fibres from which the yarns of the fabric are made.
• all the yarns from which the fabric is made contain both a certain amount of stainless steel fibres, and a certain amount of non-metal fibres.
• each yarn contains at least 0.5 wt-% of stainless-steel fibres, for example at least 1 wt-% fibres, such as at least 5 wt-% or at least 8 wt-% fibres. The higher the percentage of stainless-steel fibres by weight, the lower the electrical resistance, and the better the protection against the effect of electroshock weapons.
• the fabrics made from the yarns described above preferably comprise at least 1 g/m 2 of stainless-steel fibres, for example at least 2 g/m 2 of stainless-steel fibres, preferably at least 10 g/m 2 of stainless-steel fibres and more especially at least 16 g/m 2 of stainless-steel fibres.
• the other, non-metallic fibres for which the yarns of the fabric are made are chosen from a group comprising natural, artificial or synthetic fibres.
• the fibres from which the yarns of the fabric are made are chosen according to the other properties the fabric in question is required to have, and are for example aramids, modacrylic and FR viscose for making a fireproof fabric, or they are cotton, PES, PA, wool, etc. for purposes of comfort and appearance.
• the said fabric comprises a first group of stainless-steel filaments and a second group of stainless-steel filaments, which extend respectively in the longitudinal and transverse direction of the fabric.
• the maximum distance at which two stainless-steel filaments can lie from each other is the same as the diameter of the electrodes in the electroshock weapon. This prevents the electrodes from coming into contact with a non-conducting yarn, and it prevents undesirable sparking.
• the stainless-steel filaments of the same group are laid at a distance of at most 1.5 mm from one another.
• Another aim of the present patent application relates to the use of stainless-steel fibres or mutually perpendicular stainless-steel filaments in fabrics that are suitable for making protective clothes against electroshock weapons.
• the present invention relates to a fabric that is suitable for making protective clothes against electroshock weapons, so that police and other security personnel can adequately protect themselves from the effect of these weapons.
• the present invention provides a fabric, which can be of the woven, knitted or non-woven type, is suitable for making protective clothes against electroshock weapons, and comprises electrically conducting elements, the electrically conducting elements being formed either by stainless-steel fibres or by mutually perpendicular stainless-steel filaments, and the said fabric having an electrical resistance of at most 10 5 ohm, measured according to European Standard EN 1149-1.
• the presence of sufficient stainless-steel fibres or stainless-steel filaments in the fabric ensures a higher conductivity for the fabric than the conductivity of the human body, so that the electrical charge issuing from the electroshock weapon is dissipated through the fabric, and no harm comes to the person wearing the protective clothes made from this fabric.
• the stainless-steel fibres are made of stainless steel having a certain composition, such as for example type 304 or type 316.
• Stainless steel 304 has for example the following composition: ⁇ 0.08% of C, 17.5-20% of Cr, 8-11% of Ni, ⁇ 2.0% of Mn, ⁇ 1% of Si, ⁇ 0.045% of P and ⁇ 0.03% of S, the rest being Fe.
• Stainless steel 316 has for example the following composition: ⁇ 0.03% of C, 16-18.5% of Cr, 10-14% of Ni, 2-3% of Mo, ⁇ 2% of Mn, ⁇ 1% of Si, ⁇ 0.04% of P and ⁇ 0.03% of S. All these quantities are expressed in percentages by weight.
• the stainless-steel fibres are made by the bundled drawing process. This method is described e.g. in the following patent documents: US-A-2,050,298 , US-A-3,277,564 and US-A-3,394,213 .
• the process starts with stainless-steel wires that are covered with a coating of iron or copper.
• a bundle of these coated wires is then enclosed in a metal pipe.
• the resulting pipe is reduced in diameter by successive drawing operations. This gives a composite bundle with a smaller diameter.
• the successive drawing stages can alternate with a suitable heat treatment in order to make further drawing possible or easier.
• This converts the wires in the composite bundle into thin fibres, which are individually embedded in a matrix of the coating material - copper or iron.
• Such a bundle normally contains 500-1500 fibres.
• the coating material is removed by etching it out with an acid. The final result is an uncoated fibre bundle.
• the fabric according to the invention can be obtained in one of two ways.
• the stainless-steel fibres e.g. stainless-steel fibres sold under the commercial name of Bekinox ®
• the fibres used for making the fabric preferably by intimate mixing.
• 10 wt-% of stainless-steel fibres can be mixed with 90 wt-% of other fibres, which can be natural, artificial or synthetic in origin.
• These "other fibres” are principally chosen according to the other characteristics required for the fabric in question, and can be for example aramids, modacrylic or FR viscose in order to obtain a fireproof fabric, or they can be cotton, PES, PA, wool, etc. for purposes of comfort and appearance.
• stainless-steel fibres are used whose length and fineness are as close to the characteristics of the "other fibres" as possible.
• stainless-steel fibres and aramid fibres are intimately mixed together, stainless-steel fibres of 6.5-22 microns and a fibre length of about 3-10 cm can be chosen, depending on the spinning method used.
• the fabric In addition to “intimate mixing", it is possible to obtain fabrics with the required characteristics, especially a high conductivity and an associated limited resistance, by providing the fabric with mutually perpendicular stainless-steel filaments.
• the basic yarns used for making the fabric do not themselves contain stainless steel, but instead, as it were, a lattice structure of stainless-steel filaments is formed in the fabric.
• the fabric in question contains mutually perpendicular stainless-steel filaments extending both in the longitudinal and in the transverse direction of the fabric.
• the different filaments lie sufficiently close to one another, so that a fine lattice structure is obtained.
• the maximum distance at which two stainless-steel filaments can lie from each other is the same as the diameter of the electrodes in the electroshock weapon. This prevents the electrodes from coming into contact with a non-conducting yarn, and prevents undesirable sparking.
• the present invention also relates to the use of stainless-steel fibres or mutually perpendicular stainless-steel filaments in fabrics that are suitable for making protective clothes against electroshock weapons.
• the patent proprietor prepared a number of fabrics according to the invention, which were then subjected to the following test: the fabric was pressed against the arm of a volunteer, and a hand-held electroshock weapon was then brought into contact with the fabric. The volunteer described the resulting sensation in the case of each fabric.
• the electrical resistance of the corresponding fabric was also measured according to European Standard EN 1149-1, using an annular electrode with a distance of 10 mm between the two rings. The resulting value of O was multiplied by a factor of 19.8 in order to obtain the value in units of ohm/square. This factor is specific for the annular electrode used.
• Fabric 1 was made of a modacrylic-cotton blend and contained a lattice of mutually perpendicular stainless-steel filaments laid at a distance of 1 cm from one another.
• the fabric had the following characteristics:
• Fabric 2 was made of aramid fibres, mixed with stainless-steel fibres, and had the following characteristics:
• Fabric 2 contained 13.6 g of stainless steel per square metre. This fabric offered a good protection against hand-held electroshock weapons, for the volunteer did not feel anything. The electrical resistance obtained for this fabric was 4.4 x 10 3 O/square.
• Fabric 3 was made of polyamide fibres, mixed with stainless-steel fibres, and had the following characteristics:
• Fabric 3 therefore contained 24.7 g of stainless steel per square metre. In the case of this fabric, the volunteer again naturally did not feel anything when touched with a hand-held electroshock weapon. The electrical resistance obtained for this fabric was 2.6 x 10 3 O/square.
• the amount of stainless steel (expressed in g/m 2 ) that must be present in the fabric in order to ensure a good protection against electroshock weapons is at least 1.5 g/m 2 when the fabric is provided with mutually perpendicular stainless-steel filaments, and at least 5 g/m 2 for a minimum protection, but preferably at least 10 g/m 2 , when the fabric is provided with stainless-steel fibres.

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• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Woven Fabrics (AREA)

Priority Applications (1)

Applications Claiming Priority (1)

Publications (1)

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Cited By (2)

Citations (7)

• 2010
  • 2010-07-23 EP EP10170626A patent/EP2410281A1/de not_active Withdrawn

Patent Citations (7)

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