indigo as been used to dye textiles for centuries across many cultures. india was the earliest to cultivate the dye, and its name comes from a roman name indicum which means a product of india. it has been known in a lot of the ancient world and many other countries were producers. at planet we primarily have indigo dyed cloth from japan, india, indonesia and a number of countries in africa. indigo is natural and sustainable. more than fifty different species are used to make indigo dye but most natural indigo for sale comes from the tropics and from the species indigofera tinctoria. the plant residue can be used as a fertilizer and the water can even be used for crops.
the dye is challenging because it is not water-soluble until it has undergone a chemical transformation (reduction). several chemical manipulations are required to achieve this process and the dye bath needs to be carefully monitored in order to achieve the required result. to make it soluble, the fabric is immersed in an alkaline vat where oxygen has been removed either by fermentation or with a suitable chemical. after the fabric has been immersed in the dye-bath and is exposed to oxygen, the indigo rapidly converts from a green shade to the deep blue that is much loved. multiple dips in the dye bath deepen the colour and fasten it. cotton and linen are dipped and dried 15-20 times and silk is dipped and dried over 40 times.
indigo is popular because it is fast acting, and so it is less likely to penetrate under the ties in resist-dyeing methods such as bandhani in india, shibori in japan as well as in the resist dyeing required for ikat. indigo also works at lower temperatures, so it is particularly useful for batik in that it won’t melt the resist wax.
indigo is famously used to dye traditional denim and demand for indigo increased dramatically due to levi strauss’s jeans.
in our showroom we have a large collection of products made from natural indigo dyed cloth, (even though of course there are easily available chemical blue coloured dyes). indigo has wonderful natural variations and an intensity of colour that synthetic colours never seem to match. we think that nothing surpasses the intense shades possible with natural indigo.