GB1009696A - Improvements in or relating to papermachine felts - Google Patents

Abstract

A paper-machine felt is made by weaving a base structure of more than one layer so as to have both mutually united front and back layers therein of which the back layer is formed so as to contribute the major proportion of the tensile strength of the base of the front layer is composed wholly or mainly of wool and then needling the front layer into and on to the back layer. The base structure may be a duplex fabric, i.e. two single woven plies bound together during weaving by binder yarns, or a semi-duplex fabric, i.e. a fabric which comprises either two layers of warp threads woven together with a common weft or two layers of weft threads weaving with a common warp. Preferably, the base structure is woven tubular with yarns of lower twist in the outer layer and yarns of harder twist in the inner layer and is transferred to a needling machine wherein the weft yarns become the circumferentially lengthwise yarns. After needling, the felt is turned inside out and a further needling operation is carried out on the now outermost layer. The yarns of the front layer are spun yarns containing at least 70% of wool fibres and at most 30% of synthetic fibres. The yarns of the back layer may be composed wholly of wool or may be spun from a blend of wool and synthetic fibres or may be formed by twisting together a wool yarn and a continuous multi-filament synthetic yarn or may be formed by twisting a yarn spun from a blend of wool and synthetic fibres with a continuous multifiliament synthetic yarn or may be composed entirely of synthetic fibres or continuous synthetic multifilaments.