Information about the process run 1.
Material
Cotton weave, 440 g per running meter Warp, sized with a blend of Corn starch Polyvinyl alcohol Polyacrylate Wax
2.
Previous process 1st Step: 2nd Step: 3rd Step:
3.
Enzymatic desizing, dwelling process a) Washing-off decomposed starch b) Alkali-Pad Steam Peroxide-Pad steam
Process 1st Step: 2nd Step:
Combined alkali + oxidative treatment, dwelling process a) Washing-off solubilized impurities and decomposed starch b) Peroxide-Pad steam 3.1 Advantages of the oxidative desizing in the alkali step - Maximum swelling of cellulose, breaking up of husks, saponification of waxes and grease. - Persulphate decomposes starch as well as polyvinyl alcohol - Alkali solubilizes polyacrylate - Shorter dwell time (4 hours) as compared to enzymatic desizing Remarks : Padding at 90ÂşC, covering of batching roller with foil Temperature is kept due to exothermic reactions: Starch + Persulphate exothermic > Polyvinylalcohol + Persulphate exothermic > 3.2
Calculation of feed liquor concentration F1 = 60% (Entry mangle) F2 = 90% (Exit mangle) 2 d = 30% 90 F2 – F1
= 90 = factor 3 90-60