SUBJ-20:
Polyester (PES) Discharge/Disperse Discharge through Alkali (Soda Ash, Na2CO3)
Chemicals:
Synthetic Thickener (Polysacchride), Soda Ash, Sodium Hydro sulfite and Caustic for Reduction Cleaning (although not necessary, it is done to have shin and glorious effect), Disperse Dyes
1. Stable to Alkali
2. Not Stable to Alkali.
Bit Discussion:
Polyester dyed or printed fabric can also be discharged but discharging requires more severe conditions like chemicals and parameters to obtain good results. Discharge of Polyester is more crucial and every dye cannot be discharged.
Normally there are two ways to Discharge a polyester fabric printed through Disperse dyes. First, utilization of simple alkali like soda ash which provides alkaline medium required to carry out discharge and other is done through utilization of Ragolit C and Tin Chloride.
Here in this post we are going to utilize former method in which we will be discharging though alkali soda ash. There are two kind of disperse dyes. One, Which are not stable to Alkaline medium at all and Second, Those disperse dyes which can bit stand with alkaline medium. So, this is basic principle which we are going to utilize in our both discharges, white and color Discharge.
Process:
Dyeing Recipe:
Padding Liquor{Continuous Process}
Disperse Dye (Not stable to Alkali) 30 g/Kg
Acetic Acid To Adjust Ph between 5-6
Water Balance
Total 1 Kg
Pad at pressure 2bar with pick up 70 to 80.
Dry at 110C° for 1Min.
After Dyeing, Not fixed Yet and remember, we need not to fix it here.
