Evaluation Of Prickle And Anti-Prickle Finishing Of Ramie Fabrics

Ramie is a textile material with dominant resources in China, and ramie fabric is wellknown with its cool, breathable, antibacterial performance and wild natural style. However, thefabric stiffness, roughness and prickle-itching characteristics caused by high degree ofcrystallinity and great rigidity of ramie fibers have seriously affected the comfortability of ramiefabrics, so that the development and application of high-grade ramie fabrics are restricted..Firstly, a BP neural network model related to KES fabric mechanical indexes and subjectiveevaluation of prickle rating is designed, and a new objective evaluation method of fabric prickleis constructed. The results show that the model had the characteristics of an extremely fastconvergence and a relatively high accuracy. The prickle sensation could be easily obtained fromfabric mechanical properties measured by KES system. Therefore, this objective evaluation is aconcise, convenient and feasible method.Secondly, an effective anti-prickle finishing of ramie fabrics is developed by optimizing andcombining cellulase and polyurethane finishing processes. The results show that the hairiness onramie fabric surface is partly softened or removed by appropriate cellulase finishing, which ishelpful to improve fabric surface smoothness. However, the decrease of prickle sensation islimited by this cellulase finishing. Polyurethane finishing of ramie fabrics can significantlydecrease the fabric prickle property, due to the improvement in fabric surface smoothness and thedecrease in the surface hairiness by wrapping and sheathing ramie fibers or yarns. Meanwhile,the compressive property of ramie fabrics is effectively increased by cross-linking andnet-working between polyurethane and fibers. The anti-prickle effect of polyurethane-cellulasecombination finishing is similar to single polyurethane finishing, while thecellulase-polyurethane combination finishing decreases the prickle property remarkably.Moreover, the ramie fabric surface property and compressive property are improved and thebreathability and whiteness are preferably preserved. The optimized cellulase finishing process isa treatment in a solution containing1.0%(o.w.f.) of cellulase(80L) at pH4.5and55℃for90min with a bath ration of1:30, and then heat to100℃to denature cellulose enzyme, and dry atroom temperature; The optimized polyurethane treatment is followed for anti-prickle finishing by dip-nip twice with a liquor containing160g/L of PA-11at room temperature, and predryingat80℃for4min and baking at160℃for4min.Finally, the influence of NaOH-urea aqueous solution swelling system on the properties(tensile property, moisture regain and dye uptake) and structure (crystallinity and morphology) oframie yarns are investigated, making useful explorations for reducing ramie fabric prickle. Theresults show that, The breaking strength of ramie yarn is slightly lowered, and the elongation atbreak and accessibility are significantly increased, and the crystallinity and stiffness aresubstantially decreased after alkali/urea relaxation treatment. This method is of significantinterest to reducing ramie fabric prickle property. The breaking strength and elongation at breakand accessibility of ramie yarn are slightly increased. At the same time, the crystallinity andstiffness have a minor reduction after NaOH/urea treatment with low tension. Although theeffect of anti-itch under tension treatment is less than on the role of relaxation process, themechanical properties of ramie yarn are enhanced and other aspects of quality has a positivemeaning, suggesting a potential application value.