Comparative Study on Crease Recovery Finishing of Silk Fabric with Citric Acid and Dimethylol Dihydroxy Ethylene Urea (DMDHEU) as Finishing Agent

In this research work, an attempt was made to increase the crease resistant property of silk fabrics by using citric acid and dimethylol dihydroxy ethylene urea (DMDHEU) as crosslinking agents. Variables were curing time, curing temperature, concentration of catalysts and crosslinking agents. Sodium hypophosphite (NaPO₂H₂) and magnesium chloride (MgCl₂) were used as catalyst for citric acid and DMDHEU respectively and silicone was used as softener. The properties of the treated fabrics like crease recovery angle (CRA), whiteness index, tensile strength, tear strength and stiffness were measured and compared with the untreated fabric. The results report that 150°C curing temperature and 2 minutes curing time is suitable for both citric acid and DMDHEU as with increasing curing temperature and time whiteness index reduces (around 23% in case of citric acid and 27.55% in case of DMDHEU). Samples treated with dimethylol dihydroxy ethylene urea (DMDHEU) shows better crease recovery angle (up to 189°) than citric acid (up to 161°). The finished fabrics treated with citric acid retained 81.51% to 99.81% breaking strength and there was an increase in its tear strength (up to 121%). On the other hand, the finished fabric treated with dimethylol dihydroxy ethylene urea (DMDHEU) retained 82.12% to 97.89% breaking strength and showed maximum tear strength retention (%) of 123%. The drape co-efficient of fabrics treated with both finishing agents were increased significantly