Mixed acrylic bulky yarns

1,148,215. Mixed acrylic bulky yarns. ASAHI KASEI KOGYO K.K. 2 Jan., 1967, No. 72/67. Heading B5B. [Also in Division Dl] Mixed acrylic bulky yarns consist of non- shrinkable or only slightly shrinkable fibres N consisting of either a homopolymer of acrylonitrile or a copolymer of acrylonitrile containing at least 50% by weight of copolymerized acrylonitrile; synthetic polymer non-conjugate shrinkable fibres S; and conjugate fibres C containing at least 50% by weight of polymerized acrylonitrile and consisting of two or more different components bonded together along their length, the components being disposed eccentrically with respect to one another in the cross-section of the fibre; the shrinkage # and the latent crimping rate 8 (both as hereinbefore defined) being in the ranges:- for N: 0##n#4; for S : 5##5#35; for C: 0##c#8; 10##c#35; and the percentages by weight of N, S and C satisfying the following requirements:- N+S+C=100; N#15; C#25; 50#S#10. The shrinkable fibres S may consist of either a homopolymer of acrylonitrile or a copolymer of acrylonitrile containing more than 50% by weight of copolymerized acrylonitrile. At least one of the components of the conjugate fibres C may be a copolymer of (i) acrylonitrile, (ii) acrylamide, (iii) a methallyl sulphonic acid ester or an acrylic acid or methacrylic acid ester of a sulphoalcohol, and optionally (iv) one or more other ethylenically unsaturated monomers, in the proportions by weight, of (i) over 80%, (ii) 4À5 to 12%, (iii) 0À1 to 2% and (iv) 0 to 15À4%, the average proportion of this copolymer component of the conjugate fibres C being 30 to 80% by weight based on the whole conjugate fibre. The shrinkable fibres S may be mainly positioned in a stretched state in the central portion of the yarn, the conjugate fibres C may mainly surround this central portion and the fibres N may mainly surround the conjugate fibres and form the outer surface of the yarn.