A lattice or mat of fine polyethyleneterephthalate fibres glued together in bundles is stretched above a film of polyethyleneterephthalate whose valencies have been saturated with fluorine. The two layers are led together through a wide slit die to a drying chamber into which is introduced a sparingly-flammable elastomer e.g. Fluorell (RTM), Viton (RTM) at 220 atmos. The surface of the lattice and the film are completely covered with elastomer whereby the non-slip coating on the lattice is dissolved by the volatile solvent, e.g. a ketone, of the elastomer. The film and lattice are brought together in the drying chamber and the volatile solvent is removed by a hot air stream. A top layer of fluorinated polyethyleneterephthalate film is applied and the whole is compressed in a heated laminating machine. At a cylinder pressure of 15 kp/cm2 and at 170 degrees C, the separate fibres of the lattice spread out to a flat network and bond intimately to the enclosing films. The prod. so derived is allowed to rest rolled up under strain for 70 hours before applying the required base colour. Known camouflage nets, based on polyamide fabrics coated with olive green PVC pastes have the disadvantages that the PVC plasticiser migrates, befouls the surface of the fabric, alters the infra-red emmission values of the organic pigments and quickly imparis their effectiveness. This invention increases life-span of camouflage nets, permits mechanical printing of camouflage patterns and simplifies storage.
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