Patent GB-763364-A (GB)
Title: Improvements in or relating to the treatment of threads
IPC: D06B17/02
Filed: 1954-02-22
Abstract: <PICT:0763364/IV(a)/1> Artificial threads are continuously treated by continuously dropping the threads under the action of gravity into the longer limb of a J-shape receptacle, which is kept with its longer limb substantially vertical and its curved portion lowermost, continuously allowing the threads to slide loosely and in folds through the longer limb and thence into the curved portion, owing to the difference in the weight of the threads in the longer and shorter limbs, continuously treating the threads in the curved portion with a liquid and/or vapour, and continuously withdrawing the treated threads from the shorter limb through an aperture at or near its free end.  The treatment may also be effected in the lower part of the longer limb of the J-shaped receptacle.  The process may be used to effect or complete the regeneration of cellulose in the production of viscose rayon, for the diffusion of residual solvent contained in cellulose acetate filaments, or for the continuous dyeing of threads. As shown in Fig. 1, a tow 11 of continuous cellulose xanthate filaments incompletely converted into regenerated cellulose is delivered by a roller 12, which is oscillated horizontally by means not shown, so that the tow falls into the 3 metre high vertical limb 13 of a J-shaped receptacle 14 to form a heap of coils reaching to within 1 metre of the top of the limb 13.  The cross-section of the top of the limb 13 is a rectangle whose sides are 10 and 30 cm. long and the limb 13 tapers as far as the curved portion of the J, where its cross-section is a rectangle whose sides are 5 and 15 cm. long respectively.  The height of the shorter limb 18 is 1 metre.  The tow is withdrawn through the orifice 15 by means of a draw-off device (not shown) at the same speed as it is delivered into the limb 13.  A solution for completing the coagulation of the filaments of the tow is introduced into the limb 13 through an orifice 16.  The shorter limb 18 of the receptacle may be heated to vaporize the carbon bisulphide formed in the receptacle, the vapour passing through the orifice 17 to recovery means (not shown).  In a second example a tow of superpolyamide filaments impregnated with an equal weight of a colloidal 1.4.5.8-tetraminoanthraquinone dispersion is similarly passed through a J-shaped receptacle, the cross-section of which throughout its length is an ellipse having axes of 4 and 10 cm. The longer limb of the J is vertical and the other at an angle of about 45 degrees to it.  The tow is withdrawn through the open end of the shorter limb and the tow in the receptacle is raised to a temperature of about 100 DEG  C. by the injection of steam through inlets in both limbs and in the curved lower portion of the receptacle.  In a third example, cellulose acetate filaments obtained by coagulating a solution of the acetate in acetic acid in an aqueous bath are passed successively through two J-shaped tubes similar to those of Example 2 but of uniform circular cross-section and 10 cm. diameter.  The filaments are fed into the longer limbs of the receptacles by means of rollers reciprocating horizontally both in the vertical plane of the J and at right angles thereto.  Water is continuously fed through an inlet in the lower portion of the long limb of the first J tube and discharged from the open end of the shorter limb, through which the filaments are withdrawn and passed to the second J tube. In the latter the filaments are treated with a countercurrent of water.ALSO:<PICT:0763364/IV(b)/1> Artificial threads are continuously treated by continuously dropping the threads under the action of gravity into the longer limb of a J-shaped receptacle, which is kept with its longer limb substantially vertical and its curved portion lower-most, continuously allowing the threads to slide loosely and in folds through the longer limb and thence into the curved portion, owing to the difference in the weight of the threads in the longer and shorter limbs, continuously treating the threads in the curved portion with a liquid and-or vapour and continuously withdrawing the treated threads from the shorter limb through an apeture at or near its free end.  The treatment may also be effected in the lower part of the longer limb of the J-shaped receptacle.  The process may be used to effect or complete the regeneration of cellulose in the production of viscose rayon, for the diffusion of residual solvent contained in cellulose acetate filaments, or for the continuous dyeing of threads.  As shown in Fig. 1 a tow 11 of continuous cellulose xanthate filaments incompletely converted into regenerated cellulose is delivered by a roller 12, which is oscillated horizontally by means not shown, sa that the tow falls into the 3 metre high vertical limb 13 of a J-shaped receptacle 14 to form a heap of coils reaching to within 1 metre of the top of the limb 13. The cross section of the top of the limb 13 is a rectangle whose sides are 10 and 30 cm. long and the limb 13 tapers as far as the curved portion of the J, where its cross section is a rectangle whose sides are 5 and 15 cm. long respectively.  The height of the shorter limb 18 is 1 metre.  The tow is withdrawn through the orifice 15 by means of a draw-off device (not shown) at the same speed as it is delivered into the limb 13.  A solution for completing the coagulation of the filaments of the tow is introduced into the limb 13 through an orifice 16.  The shorter limb 18 of the receptacle may be heated to vaporize the carbon bisulphide formed in the receptacle, the vapour passing through the orifice 17 to recovery means (not shown).  In a second example a tow of superpolyamide filaments impregnated with an equal weight of a colloidal 1. 4. 5. 8 - tetramino-anthraquinone dispersion is similarly passed through a J-shaped receptacle, the cross section of which throughout its length is an ellipse having axes of 4 and 10 cm.  The longer limb of the J is verticle and the other at an angle of about 45 degrees to it.  The tow is withdrawn through the open end of the shorter limb and the tow in the receptacle is raised to a temperature of about 100 DEG C. by injection of steam through inlets in both limbs and in the curved lower portion of the receptacle.  In a third example, cellulose acetate filaments obtained by coagulating a solution of the acetate in acetic acid in an aqueous bath are passed successively though two J-shaped tubes similar to those of Example 2 but of uniform circular cross section and 10 cm. diameter.  The filaments are fed into the longer limbs of the receptacles by means of rollers reciprocating horizontally both in the vertical plane of the J and at right angles thereto.  Water is continuously fed through an inlet in the lower portion of the long limb of the first J tube and discharged from the open end of the shorter limb, through which the filaments are withdrawn and passed to the second J tube.  In the latter the filaments are treated with a counter current of water.