Padma Shree Vankar - Natural Dyes for Textiles : sources, chemistry and applications

Environment; Pollution; Dyeing industry; Eco-friendly textiles; Natural dye; Cotton fabric

In India with its diversity of climatic zones and altitudes, geographic variety has resulted in a rich biodiversity that has gifted flora and fauna, which yields an array of dye-producing shrubs and perennials. The ancient people exclusively used dyestuffs of vegetables, minerals, and animal origin, all easily obtained in their own vicinity. In India, it was widely used for coloring of fabrics and other materials. In order to meet the growing demand for natural colorants, new pigment crops are being sought. The newer sources need to be tapped. However, for some sources such as Al root ( Morinda tinctoria ), manjistha, safflower, and indigo, there is an organized cultivation because of their exceptional and established versatility. Increased acreage is devoted to Al root and safflower cultivation purely because of their dye qualities. More plants need to be considered as agronomically viable plantations.

Natural dyes are basically elements of natural resources, and these dyes are generally classified as plant, animal, mineral, and microbial dyes based on their source of origin, although plants are the major sources of natural dyes. Natural dyes per se are sustainable as they are renewable and biodegradable. The experience with natural dyeing has given an insight to explore plants in the neighborhood. Finding fiber colors in plants that grow easily and fast has lead into a new world of fiber colors that give exotic shades. These natural colors have richness and luster that synthetics can never attain. It has become a common misconception that natural dyes only produce beiges and browns and other washed out shades. In reality, vibrant, fast natural colors can be produced, which are comparable with and often surpass the colors of synthetics. Apart from the sources of these dyes, it is perhaps the commitment of those propagating them and the near clinical efficiency with which dye is extracted, produced, and used, which is responsible for the unique nature of natural dyeing and producing stable coloration.

Experimental trials were carried out in domestic gardens in collaboration with botanists mainly focusing on the best conditions for the growth of dye plants in regard to soil and climatic factors. Modern cultivation system for getting maximal dye yields including optimal seeding and harvesting time and optimal fertilization procedures was adapted. The utilizable plant parts were subjected to specific dehydration processes, or the dyestuff was extracted as per the given strategy.

It will help in giving an idea about feasibility of providing high-quality natural dyes from plants, creating new opportunities for both farmers and fabric industryin line with the current consumer trends toward ethnic fabric and natural products. Several newer sources of natural dyes particularly for dyeing cotton and silk fabrics to get a gamut of colors have been explored. This will increase the availability of newer shades and new choices of fabric dyed with natural dyes.

The aim is to show feasibility of providing high-quality natural dyes from plants, creating new opportunities for both farmers and the fabric industryin line with the current consumer trends toward ethnic fabric and natural eco-friendly products.

Many new plant sources have been explored for natural dyeing, and the following section is a brief introduction of the plants used from our screening experience. Many of them are known medicinal plants and have been shown to have potentially rich natural colorant content as well. It is imperative to make a documentation of these plants for the future use of these plants as sources of natural dyes.