Device for fixing dye in reactive dyeing

A device for dye fixing in connection with reactive dyeing of cellulose goods (6) with a padding machine (7) for applying a dye liquor (10) containing the reactive dyestuff to the goods (6), and with an air dryer (14) connected downstream of the padding machine (7) having a chamber 15 with a goods inlet and outlet (16, 17), as well as a controllable draw-off conduit (24) and a controllable recirculating fan (36), characterized in that, the chamber (15) has adjustable steam injectors (30), that a climate measuring device (35), connected with the control means (34) of the draw-off conduit (24) and the steam injectors (30), is provided for regulating a preset steam content of the ambient air, and that at the goods outlet (17) an outlet measuring device (37) for the residual outlet moisture is assigned to the goods (6) in controlled connection with the recirculating fan (36) for regulating a residual moisture of the goods (6) still capable of reacting up to the goods outlet (17), and wherein the control means comprises a first regulator (34) for regulating the chamber climate by the selective triggering of a ventilator (28) in the draw-off conduit (24) or of a valve (32) for blowing in steam through the steam injectors (30) as a function of a climate measurement in the chamber (15), and further including a second regulator (38) for regulating the drying output by means of the recirculating fan (36) as a function of an outlet measurement of the residual moisture in the goods (6).

A method for dye fixing in connection with reactive dyeing of cellulose goods (6) with a padding machine (7) for applying a dye liquor (10) containing the reactive dyestuff to the goods (6), and with an air dryer (14) connected downstream of the padding machine (7) having a chamber 15 with a goods inlet and outlet (16, 17), as well as a controllable draw-off conduit (24) and a controllable recirculating fan (36), the method comprising the steps of:

• applying a dye liquor containing a weak alkali including a reaction dye and a wetting agent;
• providing climate and residual moisture measuring devices (35, 37) assigned to the chamber (15) and the goods (6), and regulators (34, 35) of the draw-off conduit (24) and steam injectors (30) and a recirculating fan (36) for keeping the goods sufficiently moist whereby the applied dye liquor remains ready to react to bind the dye to the cellulose fibers;
• and
• retaining the goods in the chamber for a retention treatment time of a predetermined length in the air dryer with a predetermined steam content of the air for providing excellent dyeing results.