Structural investigation of spunlace nonwoven

Purpose Spunlacing is a promising nonwoven technology for the production of fabric with good handle and better structural integrity. Structural parameters such as pore size, thickness and number of binding point/entanglement between fibres are decisive for good mechanical and comfort properties of nonwoven fabrics. This study aims to focus on the effect of different process parameters on the structural change in spunlace fabrics. Design/methodology/approach Spunlacing is purely a mechanical bonding technology where high-speed jets of water strike a web to entangle the fibres. Different spunlace nonwoven structures were produced by varying processing parameters such as waterjet pressure, delivery speed, web mass and web composition as per four-factor, three-level Box–Behnken design. The effect of these parameters on the structural arrangement was studied using scanning electron microscopy. An attempt has also been made to study the changes in pore geometry and thickness of the fabrics by using response surface methodology with backward elimination. Findings Significant structural changes were observed with variation in water pressure, web mass and web composition. The test results showed that fabric produced at higher waterjet pressure has lower mean pore diameter and lower thickness. The variation in mean pore diameter and mean thickness due to waterjet pressure is around 26 and 34 per cent, respectively, at 95 per cent significance level. The web composition and web mass also significantly influence the mean pore diameter and thickness at 95 per cent significance level. There is a strong positive correlation (r = 0.523) between mean air permeability and mean pore diameter of fabric, and this correlation is significantly linear. A strong negative correlation (r = −0.627) is found between weight and air permeability of fabric. Research limitations/implications The delivery speed failed to show any significant effect; this is in contrary to the general expectation. Originality/value The effect of concurrent variation in waterjet pressure, web mass, delivery speed and web composition on the structure of spunlace nonwoven is studied, which was not reported in the literature. The effect of web composition on pore diameter of spunlace nonwoven is interesting finding. This study is expected to help in designing the spunlace nonwoven as per end uses and specifically for apparel application.