GB425392A - An improved process for after-treating artificial silk - Google Patents

Abstract

Artificial filaments are led in a helical path over a rotating cylinder, or pair of cylinders, having a smooth surface without projections, ribs or channels, and are treated by constantly renewed continuous envelopes of liquids which act simultaneously but separately at different zones of the cylinder. The liquids may be applied by spraying and after flowing in the opposite direction to that of the filaments, they may be led away through the interior of the cylinder. The cylinder may have a hollow shaft and its surface may be porous or perforated. Liquid may be withdrawn from the surface inwardly by the application of suction. Alternatively, the cylinder is arranged vertically and constructed with separate cylindrical parts, the lower edge of each having a smaller periphery than the upper edge of the next lower part so that liquid draining from the upper part is led away through the interior of the lower part. The separate cylindrical parts may abut with castellated or zig-zag edges, the <PICT:0425392/IV/1> <PICT:0425392/IV/2> <PICT:0425392/IV/3> <PICT:0425392/IV/4> <PICT:0425392/IV/5> tongues being inwardly bent without contacting. annular troughs are arranged underneath the cylinder for the spent liquid dropping off the lower edges of the cylindrical parts. Mixing of different treatment liquids is thus avoided. As shown in Fig. 1, artificial filaments 8 are advanced helically round an upright rotating cylinder 1, the separate turns being kept apart by means of guides 10. The surface is sprayed with liquids from pipes 6. The cylinder is perforated and covered with felt or other porous material. Suction is applied to the hollow shaft to remove the treating liquids. Partitions 11 in the interior of the cylinder, and separate withdrawal pipes 2 enable the liquids to be separately collected. As shown in Fig. 2, the cylinder comprises three sections 1, each sprayed with liquid from a pipe 6. The lower end of each section is bevelled so that liquid dripping from the edge is led into the interior of the adjacent lower section. The liquids are collected separately in concentric annular troughs 45. As shown in Fig. 3, the adjacent edges of the sections 1 are of zig-zag shape, the tongues 14 being inwardly bent. Treatment liquid from the upper section flows along the tongues 14 and into the interior of the lower section, and is withdrawn through the hollow shaft 2. Liquid from the lower section is collected in a trough 47. The thread loops are maintained apart by means of the inclined roller 12. As shown in Fig. 4, the adjacent edges of the sections are constructed with rectangular tongues 40, 42. The tongues 42 of the upper section are bent inwardly. As shown in Fig. 6, the cylinder is suspended vertically from an overhead bearing, and the upper section 19 is of smaller diameter than the lower section 23 so that liquid draining from it passes inside the lower section and is collected in a trough 25. Liquid from the lower section is collected in an annular trough 24.