Abstract:
Purpose – The purpose of this paper is to evaluate the efficiency of dyeing on cotton wool and silk fabrics with natural dye obtained from kitchen
waste of dry skin extract of Allium cepa.
Design/methodology/approach – The dry skin of onion produces natural dye which has been used for dyeing textiles. In the present study,
innovative dyeing with onion has been shown to give good dyeing results. Pretreatment with 2 per cent metal mordant and using 5 per cent of plant
extract (owf) was found to be optimum and showed very good fastness properties for cotton, wool and silk dyed fabrics. For effective natural dyeing
with dry skin extract of Allium cepa, conventional method of dyeing was carried out using metal mordants. The purpose of using this source was with an
idea to produce value addition dyed product from kitchen waste as the dye has very good potential of uptake, adherence to the fabric and has good
wash and light fastnesses. Results show very attractive hue colours.
Findings – The preference of using easily and cheaply available material for dyeing by conventional dyeing lowers the cost of natural dyeing and
enhances resource productivity and as a result, reduces waste. This makes onion scale one of the easily available materials for natural dyeing industry.
Research limitations/implications – Although metal mordanting with copper sulphate and potassium dichromate are not ecofriendly but we have
used only 2 per cent of these metal salts to prepare different shades with dry scales of Allium cepa extract.
Practical implications – The method developed for natural dyeing of cotton, silk and wool fabrics using skin extract of allium in conjunction with
metal mordanting has shown very deep coloration. The stepwise dyeing of cotton fabric with metal mordant by the natural dye Allium cepa showed
that the stepwise dyeing process gave very good result. The dye uptake in case of stepwise dyeing was from 65-68 per cent in the case of cotton, 70-74
per cent in silk and 78-82 per cent in wool with different mordants.
Originality/value – The method developed for natural dyeing of cotton, silk and wool fabrics using skin extract of allium in conjunction with metal
mordanting has shown marked improvement in terms of dye adherence and fastness properties and can thus be recommended for industrial
application.
