Question 54 (Textile Engineering & Fibre Science)
The add-on of a chemical finish required on a fabric is 3% on-weight-of-fabric (owf). If the wet pick up is 80%, then the concentration of finish required in the padding bath, in % (wt/wt), accurate to two decimal places is __3.50 to 4.00__.
Answer / Solution
Given in the question–
Add on the fabric=3%
Wet pick up=80%
The concentration of finish(wt/wt)=?
Let, weight of the fabric=100 kg
Formula:
Weight of chemical finish=Weight of fabric x add on%/100
Weight of chemical finish=100 x 3/100
Weight of chemical finish(oven dry wt of finish)=3 kg
By formula –
Wet pick up%=wt of dye on liquor*100/wt of fabric
80=wt of finish on liquor *100/100
Wt of finish on liquor=80 kg
By formula-
Concentration%=Oven dry wt of finsh*100/Wt of finish on liquor
Concentration%=3*100/80
Concentration%=300/80
Concentration%(wt/wt)=3.7 (Answer)