Natural dyes are the dyes and pigments obtained from renewable resources of nature, such as plant and animal, although natural dyes from minerals of the earth are also known [1]. Colouring matter derived from different organs of a plant, such as root, leaf, bark, trunk or fruit are known as vegetable dyes, while the colouring matter obtained from the animal kingdom are known as animal dyes. Natural dyes find application chiefly for colouration of food, drugs, cosmetics and textile [2]. Natural dyes are explored by craft dyers and printers for colouration of textile materials for long time [3]. After the synthesis of Mauvin by W.H.Perkin and its subsequent commercialization, the use of natural dyes receded [2, 4] and the position continued to be much the same until in the recent past growing consciousness about environmental preservation and control of pollution and conventional wisdom and belief regarding environment friendliness of natural dyes have renewed interest for use of natural dyes for the colouration of textile [5-7]. Studies related to application of some of the natural dyes on cotton, silk and wool fibres are available in the literatures [8-15]. Onion (Allium cepa) belongs to Liliaceae family and originated in the Middle East. It has been used since centuries as vegetable all over the world. The outermost dry papery skin of onion yields the dye C.I. Natural Yellow 10. The main colouring component found in the skin of onion is quercetin [16]. Marigold (Tagetes erecta) is a stout branching herb extensively cultivated in all over India and is used at religious ceremonies. The flowers mainly contain the flavonol-quercetagetol, which is a derivative of quercetol [17-18]. Tea (Camellia sinensis) is a beverage produced from leaves of the tea plant. The chief biochemical colouring compounds present in the tea liquor are theaflavin and thearubigins [19]. Palas (Butea monosperma) flower is abundantly available throughout India in deciduous forests. This tree gets up to 50 ft high with stunning flower clusters. It looses its leaves as the flowers develop during the month of January to March. The main colouring compound found in this flower is buteol [1].

The present article reports printing of handloom cotton fabric with the above vegetable colourants in presence of different inorganic salts, like aluminium sulphate, ferrous sulphate and copper sulphate and to assess different colourfastness properties of those printed textile. The present work was undertaken keeping the scope and growing demand for environmentally safe natural printed handloom textile products in view.

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The Authors are associated with Visva-Bharati University, Department of Silpa Sadana.West Bengal