Dyeability of red cabbage colorant on silk fabric treated with Entada Spiralis / Najihah Mat Shom

Natural dyes have been the focus of recent researchers due to their unique colour shades and environmentally friendly processes. However, dyeing with natural dyes often results in light colour shades with poor colourfastness properties. This study focuses on dyeing using red cabbage extracts on silk fabrics which were treated with Entada spiralis to produce a variety of colour shades, enhance colour properties and improve the colourfastness of the dyed fabrics. Entada spiralis, or locally known as pokok beluru, was used as a colour enhancer. The red cabbage extracts were extracted through boiling water (BWE) and ultrasound-assisted extraction (UAE) methods. The extracts were used to dye silk fabrics, which were treated with Entada spiralis, using several types of mordants. The exhaustion method was set at 85oC for 60 minutes using different liquor ratios. Both the treated and untreated silk fabrics were dyed and comparisons were made on their colour shades, properties and colourfastness to washing, perspiration, crocking and light. The results indicated that the dyed samples treated with Entada spiralis and red cabbage solution gave dark shades in colour such as dark brown, and higher colour strength, and better colourfastness. The treated dyed samples gave ratings of moderate to good colourfastness in the greyscale test. Meanwhile, the untreated dyed samples gave poor to moderate colourfastness. The UAE method at 15 minutes extraction resulted in higher colour strength at 0.208 K/S value for treated sample with iron (II) sulphate as mordant compared to the boiling water extraction (BWE) method that needed 30 minutes of extraction time with a K/S value of 0.17995. As a conclusion, the Entada spiralis treated samples with a red cabbage solution using UAE techniques gave better colourfastness properties and higher colour strength than the untreated fabrics.