Improvements in the production of patterned knitted textile fabrics

摘要

Warp knitted fabrics produced on a machine having at least three guide bars with at least two bars guiding a synthetic yarn, e.g. a polyamide, polyester, polyether ester, polyacrylonitrile, or "Spandex" yarn, and at least one further bar guiding a yarn made at least in part of natural cellulose, regenerated cellulose or cellulose acetate, are subjected at an elevated temperature in selected areas to the action of a substance which splits off an acid, e.g. aluminium chloride or sulphate, zinc nitrate, sodium bisulphate or an alkylated naphthalene sulphonic acid, and effects carbonisation of the natural cellulose, regenerated cellulose or cellulose acetate yarns in these areas, and the carbonised cellulose then removed from the fabrics so that a patterned fabric is produced. The cellulosic yarns may also contain wool or fibres of natural rubber. Prior to carbonisation the fabric may contain 25-75% by weight of the synthetic yarns and 75-25% by weight of cellulosic yarns, e.g. cotton, viscose rayon or cuprammonium rayon. The fabric may be printed with an aqueous printing composition comprising the substance which splits off an acid which may also contain tragacanth, an emulsified mineral oil, a non-ionic wetting agent, sulphonated castor oil, gum arabic and crystal gum, dried, heated with hot air or steam to effect carbonisation and the carbonised cellulose removed by washing.