Polyester or polyamide fibres or very low denatured viscose fibres, less than 1 decitex. Beginning mainly in the form of woven knitting threads, the microfibres give the thread special flexibility, since, in the same diameter, microfibre yarns can be coupled with a greater number of bait than traditional denim fibres. Fabrics made of microfibre in bow, much used for raincoats, dusters and sportswear in general, are lightweight, flexible, with spongy hand and / or hand-picked depending on the treatments done in the finishing.