GB890633A - Process for the dyeing of finished goods, especially textiles - Google Patents

Abstract

<PICT:0890633/IV (c)/1> A process for the dyeing of finished goods, especially textiles, on forms is characterized in that, after each dyeing operation, one portion of the used dye liquor is discharged and the other portion is used again for the next dyeing operation, fresh liquor of constant composition being added in an amount corresponding to the amount of used liquor discharged. As shown the process may be effected in apparatus comprising a storage container 1 connected to a dosing vessel 5 by means of a tubular conduit 2 incorporating a filter 3 and an electrically operated valve 4. A tubular conduit 7 also leads to the dosing vessel from a collection vessel 6 in which the already used liquor is stored, this conduit including a filter 8 and electrically operated valve 9. Associated with the dosing vessel is a double electrode water level control 10, the long electrode 11 of which controls the amount of fresh liquor from the reservoir and the short electrode 12 of which controls the amount of the already used liquor from vessel 6. Liquor from the dosing vessel 5 is discharged through the conduit 121 via a magnetically controlled valve 13 into a pressure vessel 14. The pressure vessel contains forms 15 carrying finished goods to be dyed, a pump 16, spray 17, steam outlet valve 18 and electrically controlled inlet for steam 19. Dye liquor circulates through pump 16, spray 17, over the finished goods and collects in the base of the pressure vessel to be acted upon by the pump again. To fill vessel 14, valve 4 is opened and fresh dye liquor from container 1 flows into the dosing vessel 5 up to the level controlled by electrode 11. Valve 4 is automatically closed and valve 9 opened. Used liquor flows from vessel 6 into vessel 5 up to the level controlled by electrode 12. Thereupon valve 13 is opened and valve 9 shut automatically, causing the dye liquor to flow into the pressure vessel. Circulation causes homeneneous mixing of the used and fresh dye liquors as the finished goods are dyed, after which pump 16 is stopped, electrically operated valve 20 is opened and the used dye liquor is forced by pressure from within vessel 14 through conduit 21 to vessel 6. Subsequently valve 20 is closed and residual steam pressure released through valve 18. In a modification (not shown) only a part of the dye liquor is discharged by use of an electrically operated valve, that part of the liquor situated below the valve being re-used in the next dyeing cycle.