Rakhi Shanker

Dyeing of cotton, wool and silk with extract of Allium cepa

– 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., – 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., – 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., – 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., – 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., – 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.

Chemical characterisation of extract derived from Daphne papyraceae and sonicator dyeing of cotton, silk and wool with the extract

Purpose – The purpose of this paper is to evaluate the efficiency of ultrasonication on new natural dye obtained from leaves and stem extracts of Daphne papyraceae using metal mordant for good cotton, silk and wool dyeing prospects. It also proposes to effect the characterisation of the colorant.Design/methodology/approach – For effective natural dyeing with leaves and stem extracts of D. papyraceae, both conventional and sonication methods for cotton, silk and wool dyeing were carried out using metal mordants. The purpose of using sonication was for betterment of dye uptake, improved dye adherence and good wash and light fastnesses. Results show marked improvement by the chosen dyeing method. Simultaneously, chemical characterisation of the colorant was carried out by first column chromatographic separation of the crude extract, followed by spectral analysis of the isolated products.Findings – The superiority of sonicator dyeing over conventional dyeing in terms of enhanced resource productivity and, as ...

Sonicator dyeing of cotton with the leaves extract Acer pectinatum Wallich

Purpose – The purpose of this paper is to evaluate the efficiency of ultrasonication on new natural dye obtained from leaves extract of Acer pectinatum Wallich using metal mordant for good cotton dyeing prospects.Design/methodology/approach – For effective natural dyeing with leaves extract of Acer pectinatum Wallich, both conventional and sonication methods of dyeing were carried out using metal mordants. The purpose of using sonication was for improvement of dye uptake, improved dye adherence and good wash and light fastnesses. Results show marked improvement by the chosen dyeing method.Findings – The superiority of sonicator dyeing over conventional dyeing in terms of enhanced resource productivity and, as a result, reduced wastes establishes it as the best available technique in the natural dyeing industry. Use of sonicator shows marked enhancement for cotton dyed fabric. Typical bath liquor to fabric ratio for conventional dyeing varies from 20:1 to 15:1 and for sonicator dyeing from only 12:1 to 10:...

Dyeing of Cotton, Silk and Wool with Bark Extract of Artocarpus Heterophyllus Lam

Artocarpus heterophyllus Lam (local name jackfruit) belongs to the family of Moraceae. It produces natural dye from the bark of the tree which has been shown as a prospective natural dye source for textiles. In the present study, innovative extraction of yellow colorants using ultrasound energy is shown. Dyeing with jackfruit bark extract has been shown to give good dyeing results. Pretreatment with 1 % metal mordant and 4 % of bark extract (owf) was found to be suitable and showed very good fastness properties for cotton, wool and silk dyed fabrics with hue colors ranging from light brown to greenish to brown. The dye uptake by cotton fabric ranged from 55-62%, 68-70% for silk and 59-73% for wool with different mordants. The effectiveness of metal mordant-artocarpus in better dye uptake appears to be an improved process resulting in good dye adherence and good fastness properties.