Indigo

Indigo dye is an organic compound with a distinctive blue colour. Historically, indigo was a natural dye extracted from plants, and this process was important economically because blue dyes were once rare.
It is used in combination with the shibory dyeing technique.
Shibori is a Japanese dyeing technique that typically involves folding, twisting or bunching cloth and binding it, then dyeing it in indigo. Whatever is used to bind the fabric will resist the dye, resulting in areas of the cloth that take the distinctive blue dye in patterns created by the resistance, and other areas of the cloth that remain white. Shibori is a very vast technique and there are tons of ways to do it (and a truly infinite number of patterns you can create), but in this post we’re going to look at two methods: using wood blocks and rubber bands to bind and resist the dye.