Anti-Pilling Application Of Cellulases On Low-Twisted Cotton Fabircs

Low-twisted fabrics are popular nowadays because of their bulky and soft handle. However, due to its low twist, the pilling becomes a nerve-racking problem. With the aim of improving the pilling rate by 1 grade, in this paper 4 commercial cellulases, namely Cellusoft L, Cellusoft APL, Primafast Luna RL(Luna for short), Cellusoft CR consisting different composition were used on both circular knitted and flat knitted fabrics.For Cellusoft L and Luna, orthogonal experiments indicated there existed interaction among the 4 process parameters namely pH value, temperature, enzyme dosage and treaded time while the enzyme dosage had a great influence on the pilling rate.Furthermore, one way analysis of enzyme dosage showed for the flat knitted fabric, all of these 4 cellulases within the operational range could enhance its pilling rate by 1 grade. But when considered from efficiency, Cellusoft L performed better than other 3 cellulases. For the circular knitted fabric, Cellusoft L and Cellusoft APL acted almost in vain while Luna could increase its pilling rate by 1 grade. Therefore, it meant pilling was related to fabric structures and cellulase kind.Moreover, it was concluded by the Scheffémethod that the pilling rate of the flat knitted fabric increased only when the dosage of Cellusoft L increases from 0.5%(o.w.f) to more than l%.There is no significant pilling rate difference when its dosage changed between 1% and 5%. Optimal recipes were also given in this paper. For the flat knitted fabric, the process of Cellusoft L bypH=4.8, 50℃, 5%(o.w.f), 30min or pH=4.8, 50℃, l%(o.w.f), 60min were recommended. And for the circular knitted fabric, the process of Luna by pH=4.5, 65℃, 5%(o.w.f), 30min was recommended. Their bursting strengths could both maintain at more than 70% when treated like above.It was also discovered in average there existed logarithmic relation between the bursting strength of the flat knitted fabric and the reducing sugar concentration of its after-treatment solution.Finally, cellulase processes in combination with 2D resin, polyurethane and softening processes were researched. The handle was a little affected when combination of Cellusoft L and PU enhanced the pilling rate by 1 grade and the bursting strength for both kinds of fabrics .Although the combination of Cellusoft L and 2D resin could increase the pilling rate to more than 4.5, it was not applicable due to the great strength loss. The pilling rate could be kept at 2.5 if the softener dosage was adjusted high.