GB347235A - Improvements in or relating to dyeing - Google Patents

Abstract

Circulating or passing fluids through travelling materials.-Relates to a process and apparatus for the dyeing of textiles, preferably at a comparatively high speed, the yarn or fabric being passed through the dyeing vat in an extended condition, while the dye liquor is circulated so that by reason of pressure differences it flows through the material, whereby <PICT:0347235/IV/1> <PICT:0347235/IV/2> <PICT:0347235/IV/3> <PICT:0347235/IV/4> <PICT:0347235/IV/5> the fabric is distended more or less, th liquor being applied to and withdrawn from the material by means arranged so that the pressure differences act on a length of material which is freely suspended in the liquor and guided out of forcible contact with the means. The speed of transit and the rate of propulsion of the liquor are preferably arranged near the maximum point allowed by the texture of the fabric so that it is dyed to the required shade by a single passage through the vat, the latter being kept at a desirable temperature e.g. by heating coils submerged therein. The rapidity of transit is stated to allow of the dyeing of woollen goods &c. which are permanently injured by lengthened contact with certain dyes. For the treatment of flat piece material, or beamed warps of yarn, the material is guided and drawn by rollers j, j3, Fig. 1, through a vat a between two sets of pipes f respectively perforated, in staggered fashion, on their upper and lower sides so that jets of liquor are directed at an angle towards and through the material, to extend same, being sucked from connections b and returned by pump d through pipe e. Fresh dye equivalent to the amount extracted by the passing material is added continuously from tank l through pipe l1. In a modification, Fig. 5, the vat is formed with two sets of vertical perforated plates between which the fabric &c. passes, the dye being forced outwardly from the central compartment a4, across the spaces a1, a2 through the material, being finally returned via pipe c. A single immersed guide roller m is provided. For the treatment of tubular fabrics, which may be flat piece fabric those selvages have been joined, the fabric is loaded on to swivel pipes q3, q4, Figs. 3 an 4, supplying liquor via a three-way cock q to an immersed pipe p1 whose whole submerged area is perforated. The pipe q3 say, is swung away from the cock q and material is drawn from pipes q4, p1 being held and dyed in a distended condition by the action of the radially impacting liquor jets. As the following end of the material approaches q it is connected to the loading on pipe q3, which is then connected to cock q, pipe q4 being swung away, so that a continuous process is possible. The end p2 of the pipe is preferably flattened and looped to allow for the transformation of shape of the fabric in approaching the draw rollers j3. Instead of pipes q3, q4 a single pipe may be employed, the pipe p1 admitting of a swivel action so that it can be moved above the vat for loading on the material. The apparatus shown in Fig. 5 can be modified for tubular goods by having an immersed perforated U tube in a U-shaped casing the action being as described in reference to Figs. 3 and 4. Steam pipes k are provided in each case for temperature adjustment. For dyeing stockings &c. a continuously rotating drum, which may rotate at a speed of half revolution per minute, is employed, Fig. 14, the liquid being supplied to the hollow spindle t and escaping by nozzles s upon which the stockings are attached. The drum has dovetail grooves o allowing for the speedy fitting and removal of slides r each containing a row of nozzles. The liquor in the vat extends up to the centre of the rotating drum and deflecting means such as a baffle-plate t2 prevents the radially moving liquor from escaping upwardly while rows of stockings are being positioned. In an example the bath was made from 650 gallons of water, 60 pints of caustic at 66 DEG Tw. and 3 lbs. of hydrosulphite. To this was added 20 lbs. of colour paste which had been previously vatted. This liquor was circulated at the rate of 650 gallons per minute and maintained at 112 DEG F. The treated fabric was moved at a speed of 1 1/4 lbs per minute and fresh dye was added from tank l at the rate of 12 1/2 per cent of weight of fabric passing.