Abstract
In discharge printing of cotton fabrics dyed with C.I. Reactive Orange 16(O-16), C.I. Reactive Blue 19(B-19) and C.I. Reactive Black 5(Bl-5), when the dyes were discharged by some chemicals, such as $K_{2}CO_{3}$, BASB, DSR, sarcosine and GSB, the single use of those chemicals made a very poor discharge, but mixing them with $K_{2}CO_{3}$ resulted to the outstanding improvement of discharge. Especially the dischargeability of $K_{2}CO_{3}$ BASB or $K_{2}CO_{3}$+DSR was very gratifying. For O―16, $K_{2}CO_{3}$+ DSR was slightly more effective than $K_{2}$CO$_{3}$+BASB, but for B―19 and Bl―5 $K_{2}CO_{3}$+BASB and $K_{2}CO_{3}$+DSR showed similar good results. In discharging of O―16 and B―19 by $K_{2}CO_{3}$+BASB or $K_{2}CO_{3}$ +DSR, the dischargeabilities of them increased as the time of 102$^{\circ}C$ steaming increased under the condition of 102$^{\circ}C$ steaming and no baking, but not under the condition of 102$^{\circ}C$ steaming and 16$0^{\circ}C$ baking. However for Bl-5, without regard to baking, the 102$^{\circ}C$ steaming of more than 15 minutes caused the discharge to be much more remarkable than that of 8 minutes did. Generally baking elevated the dischargeability, and this was sure in discharging by $K_{2}CO_{3}$+BASB or $K_{2}CO_{3}$+DSR. And it was confirmed that the structure of vinylsulfonyl reactive dyes could effect on the dischargeability because the three dyes, though little, showed different discharge behaviors.