Colour stability and performance of vegetal dyes on natural fibres

Abstract

In the past natural dyestuffs were employed extensively to colour textiles, but their use has been progressively substituted by synthetic colours. Nowadays, we assist to a renewed interest being natural products safer both for humans and environment. The respect of nature and human health underlies the search for low-impact production methodologies and materials; anyway, the choice of colours and fibres should ensure long-lasting and stable visual performance. In this work we investigated the chromatic robustness of some dyestuffs on cotton and silk samples; we also evaluated the colour changes they underwent after repeated washes or exposition to direct sunlight. Vegetal Woad, Weld and Madder, produced at the Museum of Natural Colours in Lamoli (PU, Italy) by non-dangerous traditional techniques, were selected to colour our sample textiles. The results of this investigation would provide useful guidelines towards dyeing processes, in the full respect of the environment.