Indigo was originally made from two plants; Woad, Isatis tinctoria, a native of Greece and Italy, and Indigo, Indigofera tinctoria, a native of India. Color changes to greenish yellow in alkaline medium. The product is entirely herbal and safe on the skin and has medical properties. Indigofera tinctoria is used as dye on all types of yarn and fabrics. Indigo is among the oldest dyes to be used for textile dyeing and printing in many Asian countries. India is believed to be the oldest center of indigo dyeing. Natural indigo was the only source of the dye until about 1900. Major use of indigo finds in the textile industry where it is used as blue dye to color blue jeans and other natural fabrics. Over one billion pairs of jeans around the world are dyed blue with indigo. For many years indigo was used to produce deep navy blue colors on wool. The process of dyeing cotton, wool & silk is almost same. The process is like that of vat dyes. The dye has to be dissolved in reduced state, then oxidized to get the shade blue. The Indigo Leaves are used to make hair dye as well as prepare medicated hair oil.
