First Application of Mix Metallic Salt Mordant Combinations to Develop Newer Shades on Wool with Bixa orellana Natural Dye Using Reflectance Spectroscopy

Abstract

Annatto colorants derived from Bixa orellana L. seeds have been extensively used in a wide range of food commodities such as dairy products, flour confectionery, fish, soft drinks, meat products, snack foods, and dry mixes. To exploit its use as a colorant for textiles, this research study investigates for the first time pre-mordanting of wool with bi and tri metal salt combinations using aluminum potassium sulfate, ferrous sulfate, and stannous chloride mordants in order to develop natural and beautiful shades on wool with variation in hue and tone. The dyeing was carried by exhaustion method and dyed samples were analyzed using a Reflective Spectrophotometer in terms of CIELAB (L*, a*and b*) and K/S values and washing and light fastnesses were investigated according to I.S.O. standard recommendations. In the dyeing experiments, wool samples pre-mordanted with Fe + Sn displayed highest color strength followed by Fe + Al and Al + Sn combinations. The results showed that overall 36 different shades having good to very good fastness properties were produced by the use of different metallic salt combinations in the natural dyeing of wool using annatto dye.

Keywords

• annatto
• bixin
• coloring
• fastness
• mordanting
• wool