Abstract: The present invention relates to a process for the preparation of a mixture of cellulosic fibers and microfibers. Said process comprises: the preparation of a cellulosic solution (C); the extrusion of said solution (C) through the hole or holes of a die (1); the disintegration of said solution (C) when it comes out of said hole or holes by projecting a liquid or gas fluid (F) in a direction making an angle lower than or equal to 75 degrees with the axis of said die (1); said fluid (F) being neutral or appropriate to regenerate or precipitate, only partially, the cellulose; the reception in a cellulose regeneration or precipitation bath, of the dispersion generated at the disintegration step; the recovery of the mixture of fibers and microfibers, more or less bonded, obtained in said bath. Said process provides for the preparation of mixtures rich in microfibers (with a fineness lower than 1 dtex, particularly between 0.5 and 0.3 dtex).

Abstract: A sewing thread consists of from 70 to 95 percent by weight of lyocell fibre and from 5 to 30 percent by weight of at least one synthetic fibre such as polyester or polyamide. The sewing thread can be used for sewing garments, particularly those comprising a major proportion of cellulosic fibres, and can be dyed with a dyestuff for cellulose.

Abstract: Use in the manufacture of extruded lyocell articles of cellulose having a value of Pipe Flow Index (as defined) to Jet Flow Index (as defined) in the range from 0.85 to 6 can offer a number of advantages, particularly in cellulose solution transport and in spinning stability. Pipe Flow Index is designed to assess the flow performance of cellulose solution under low shear conditions typically experienced in transfer pipework. Jet Flow Index is designed to assess the flow performance of cellulose solution under high shear conditions typically experienced during extrusion.

Abstract: A wound dressing has its wound-contacting surface composed of a tow or strand of textile filaments at least 15 mm long or a fabric of textile filaments at least 3 mm long, substantially all of the filaments being non-crosslinked carboxymethylcellulose filaments capable of absorbing at least 15 times their own weight of 0.9% aqueous saline solution. The wound-contacting surface forms a swollen, transparent gel which retains sufficient fibrous character to be removable as a coherent dressing from the wound.

Abstract: The fibrillation tendency of solvent-spun fiber can be increased by subjecting the fiber to a treatment which reduces its degree of polymerisation by about 200 units or more. Suitable methods of treatment include severe bleaching, for example application of an aqueous liquor containing 0.1 to 10 percent by weight sodium hypochlorite (as available chlorine) to the fiber followed by steaming. Fiber may be treated in never-dried or previously-dried form. Fiber treated by the process of the invention is useful for example in the manufacture of paper and hydroentangled fabrics. Fiber of increased tendency to fibrillation can be beaten to a Canadian Standard Freeness 400 in the Disintegration Test by 30,000-150,000 disintegrator revolutions and to a Canadian Standard Freeness 200 in the same Test by 50,000-200,000 disintegrator revolutions.

Abstract: A method of producing lyocell fibers by spinning a solution of cellulose in an organic solvent through an air gap and into a spin bath in which there is provided a cross-draught of air in the air gap.

Abstract: A method of producing lyocell fibres by spinning a solution of cellulose in an organic solvent through an air gap and into a spin bath in which there is provided a cross-draught of air in the air gap.

Abstract: A method is described for forming a solution of cellulose in a tertiary amine oxide (such as N-methylmorpholine N-oxide) and a non-solvent for cellulose (such as water). The method involves the preparation of a mixture containing excess non-solvent, and removing the excess by heating the mixture to a temperature in excess of the boiling point of the non-solvent at a predetermined sub-atmospheric pressure, and feeding the heated mixture into the introduction zone of a mixing chamber at the predetermined sub-atmospheric pressure, so as to cause flash evaporation of some of the excess non-solvent. The mixture in the mixing chamber is then agitated by a rotor and transported through the mixing chamber whilst further evaporation of the non-solvent occurs. The cellulose solution thus formed is extracted from the mixing chamber, and the evaporated non-solvent withdrawn in cocurrent mode from the same end of the mixing chamber. Apparatus for carrying out the method is also described.