GB383627A - Improvements in or relating to the treatment of vegetable fibres - Google Patents

Abstract

383,627. Obtaining fibres. HAUGHEY, T. P., Stonewall Apartments, Danville, Virginia, U.S.A. May 15, 1931, No. 14461. Convention date, May 16, 1930. [Class 120 (i).] Fibres of flax, hemp, or the like are prepared for spinning by cutting partially decorticated fibres into lengths suitable for spinning, digesting the cut fibres in a weak chemical solution to dissolve the gum, and separating the fibres from the gum, the process preferably being carried out at a temperature less than 180‹ F. In an example, flax straw is decorticated, cut into the desired lengths, and tied into bundles which are kept straight on frames. The fibres are thoroughly washed in cold water and treated with a very dilute solution of potassium permanganate at 4-20 lbs. per sq. inch up to 40 mins. without heating. Alternative chemicals are other permanganates, caustic soda, saponifying or sulphonating oils such as castor, olive, linseed, soya or cottonseed oils, or distillates such as alcohol and glycerine, the strength of the solution being about # - ¢ per cent. Vacuum is then applied and air introduced at the bottom of the vessel, whereby violent agitation ensues and the gum and remaining shives rise to the surface. The gum may be recovered. This treatment causes the ends of the fibre bundles to taper and fray, whereby subsequent operations are facilitated. The fibres are washed, drained and squeezed and put into a mechanical beater, and, if necessary, neutralized with a very dilute acid solution, e.g. oxalic, sulphuric, phosphoric or acetic acid, and finally treated with a <1>/5 per cent solution of a silk softener. If further bleaching is required, chlorine water may be added to the water in the beater. The fibres are removed from the beater and passed to a mechanical picker, and dried with a warm air blast.