The purpose of this research was to study the dyeing polyamide/elastane fabric with natural indigo using exhaustion dyeing process. The effects from the concentration of the natural indigo dye thiourea dioxide and sodium hydroxide were investigated. The colour of each dyed material was investigated in term of the CIELAB (L* a* and b*) and K/S value. The color fastness to washing rubbing perspirdation light water sea water and chlorinated water of the dyed samples was determined. The bursting strengrh of dyed polyamide/elastane was evaluated. The best vatting condition was at 50 ̊C for 30 minutes. The optimal formula of dyeing polyamide/elastane fabric using natural indigo was prepared by mixing 200 g/L natural indigo paste 60 g/L thiourea dioxide 1 g/L sodium hydroxide. The fabric dyed in the solution of indigo vatting a shade of dark blue colour. The color fastness to light washing water sea water perspiration and chlorinated water were good to very good. However the rubbing fastness results showed fair level. The bursting strength of dyed fabrics is less than the undyed fabric 3.1%. The optimal ratio of discharge printing on polyamide/elastane fabric were compose of 70 % starch print paste and 30 % discharging agent (KMnO4). The pattern design produced from these combinations in the printing areas on fabrics showed an excellent standard of printing quality. The results confirmed that natural indigo dyes have potential applications in polyamide/elastane fabric dyeing and the dyed fabric can be used produce women’s intimate apparel.

This study aims to investigate on the adjustment of texture and indigo dye using natural substance on Sisal fibre. Temperature time period conditions of texture adjustment process and ombre dying techniques on braided Sisal fibre are used as focal factors of the study. To elaborate further the proper condition to alter braided Sisal fibre is by using softening agent and Surfactant each for 5 grams per litre at the temperature of 50 degree Celsius for 30 minutes as a result the tensile strength of the processed fibre has been reduced compared to the pre-processed ones. After the adjustment process the fabric will be dyed in natural indigo dye with 5 distinctive pigment concentrations of 20 30 40 100 and 200 grams per litre respectively. The colour fastness to washing is at good to high level while artificial light fastness is at an excellent level (level 8). The colour fastness to rubbing under dry condition of the deepest pigment (of 200 grams per litre) indigo-dyed braided Sisal fibre simmered with Sodium Hydroxide and boiled with softening agent and Surfactant is at low level and the colour fastness to rubbing under wet condition of the deepest pigment (of 200 grams per litre) indigo-dyed braided Sisal fibre simmered in Sodium Hydroxide and boiled with softening agent and Surfactant is relatively low to average. Thus it indicates that the softening agent could adjust Sisal fibre and its texture to be smoother and natural indigo dye could be adapted to dying Sisal textile as well.