CHEMICAL FINISHING OF COTTON .2. COMBINED EASY-CARE FLAME RETARDANCY FINISHING OF COTTON

Treatment of cotton fabric with etherified methylolated melamine (MM) alone or in admixture with dimethylodihydroxy ethylene urea (DMDHEU) a long with Pyrovatex Cp was investigated to render the cotton fabric cr ease resistant and flame retardant. The treatment was carried out unde r different conditions including nature of catalyst, ratios of EMM and DMDHEU in their binary mixture and incorporation of silicon-elastomer s, other polymeric products, as well as pre-polymerized EMM in the tre ating solution. Of all several catalysts examined, ammonium sulphate p roved to be the best one for combined easy-care and flame retardancy f inishing using EMM/Pyrovatex Cp mixture. The use of EMM/DMDHEU at diff erent ratios, along with Pyrovatex Cp, did not perturb the individual contribution of EMM and DMDHEU in nitrogen content, crease recovery an d strength losses of the fabric. Flame retardancy was greater at highe r ratios of EMM in the EMM/DMDHEU mixture. Incorporation of certain si licon elastomers in the EMM/Pyrovatex Cp treating solution enhanced th e easy-care and flame retardancy properties of the finished fabric wit hout adversely affecting strength properties. On the other hand, incor poration of pre-polymerized EMM in a treating solution containing EMM and Pyrovatex Cp caused substantial changes in easy-care and flame ret arding properties of the finished fabric, depending upon the pH of bot h pre-polymerization and treating solution. The use of EMM pre-polymer ization at pH 6 brought about a finished fabric with significant flame retardancy beside a crease recovery of 250-degrees and retained stren gth of ca. 77 %.