ECO-friendly durable press finishing of cellulose-containing fabrics

To impart easy-care properties to cellulose-containing fabrics along with avoiding any harmful effects of formaldehyde on both the health and the environment, attempts have been made to use citric acid (CA) as an ester crosslinking agent along with different catalytic systems in the absence and presence of certain additives. Further, fixation conditions, type of crosslinking agent, as well as type of substrate have been studied. Results revealed that the enhancement in carboxyl content, performance properties, and the decrease in tear strength (TS) as well as in whiteness indices (WI) of the finished fabric samples were increased by increasing CA concentration up to 80 g/L and by raising thermofixation temperature from 140 up to 180degreesC for 90 s. Inclusion of triethanolamine hydrochloride (TEA. HCI), decreased the carboxyl content, TS, color strength KS, as well as oily stain release rating (SER) of the finished fabric samples along with an increase in bound nitrogen (%N), wrinkle recovery angle WRA, and an improvement in WI without affecting the durable press rating (DP). Within the range examined (0-30 g/L), increasing PEG-600 concentration improved the wet resiliency, TS, as well as WI properties of the finished samples. Increasing DMDBEU ratio in the CA/DMDHEU crosslinking system gave rise to an increase in %N, WRA (dry and wet), DP, as well as in free CH2O of finished fabrics, along with a slight improvement in WI values. On the other hand, the TS, carboxyl content, K/S, SRR values of the finished fabric samples were lower at a higher DMDHEU ratio. Increase in carboxyl content, %N, WRA (dry and wet), DP and SRR, as well as extent of post dyeing (KS) of the treated fabric samples upon using different ester crosslinking agents followed the descending order: citric acid > pyromellitic dianhydride. The opposite holds true for the TS, and WI values. Among the esterifying catalysts used, and for a given set of finishing conditions, NaH2PO2 . H2O proved to be the most effective one, and the following order of effectiveness may be drawn: NaH2PO2 - H2O > K2HPO4 > Na-3-citrate > Na-2-tartrate. Inclusion of silicone softener in the finishing formulation brought about an improvement in softeness degree, WRA, %N, DP, TS as well as IVS values along with a decrease in carboxyl content, SRR, and WI values of the treated fabric samples, regardless of the used silicone softener. The performance properties of the finished fabric samples were determined by the type and nature of the substrate. (C) 2002 Wiley Periodicals, Inc.