| 摘要 |
A formed product produced by needling a fibrous web containing at least 10% by weight of fibres having an elongation at break of at least 100% at a temperature 150 C degrees below the melting point of the said fibres, heating the resultant needled felt at a temperature at or above that at which the said fibres have an elongation at break of at least 100%, and draw-forming the heated felt. These products can be used as filter materials. Figure 1 shows a deep drawn double layer filter for oil/ water separation whilst Figure 2 shows an air conditioning filter comprising a non-woven needed fabric 4 having deep drawn recesses 5 filled with absorbents and bactericides 6 and covered by an air permeable non-woven sheet 7. Fibres suitable for use in the invention are acrylonitrile-PVC copolymer fibres, undrawn polyester fibres, polyamide fibres or PVC/PVA copolymer fibres. The fibres may be mixed with other perhaps thermoplastic films and may be bonded with a thermoplastics binder. <IMAGE> |
