( 1 Research Scholar, 2 Professor, ³ Professor) Eco. Env. & Cons. 29 (3) : 2023; pp. (1355-1361) Copyright@ EM International ISSN 0971–765X Effects of selected mordants on colour characteristics of green coconut husk dye on silk Tusharbala Sahoo 1 *, Nibedita Mishra 2 and Sanjaya K. Dash³ 1 Rama Devi Women’s University, Bhubaneswar, Odisha, India 2 Govt. Women’s College (Rama Devi Women’s University), Puri, Odisha, India ³ Odisha University of Agriculture and Technology, Bhubaneswar, Odisha, India (Received 13 February, 2023; Accepted 4 April, 2023) ABSTRACT Coconut husk is a common waste material thrown away by the street vendors and coconut based food processing industries. The disposal of this waste often involves huge cost for the industries. Hence, further value addition of this waste can be rewarding. In this context, an attempt was made to extract dye from green coconut husk and to study its colouring characteristics on silk. The natural dyes need the support of mordants to acquire the properties as colour fastness to washing, rubbing as well as exposure to light. The mordants also affect the shades of colour. Thus, the colour intensity and fastness properties of silk fabric was determined after treating the fabric with five mordants, viz. copper sulphate, ferrous sulphate, aluminum sulphate, alum and citric acid. Each mordant was used at three concentrations, viz. 1, 3 and 5%. It was observed that the different mordants and their concentrations affected the final shades of colours as well as the fastness properties. In view of the treatments considered in this study, the CuSO 4 and FeSO 4 mordants at 3 and 5% levels and alum at 5% level can be recommended for application on silk. Key words: Silk, Green coconut husk dye, Mordants Introduction The green coconut husk is an important by-product of the coconut water processing industry. A huge amount of coconut husk is also thrown away by the street vendors, which often remains scattered on roadsides and open fields. Another add-on issue is that the coconut husk is not quickly biodegradable. In this context, further value addition of coconut husk can be very rewarding for the producers and processors and in addition to reducing the food pro- cessing wastes; it can also help in protecting envi- ronment. An important application of the green co- conut husk could be in the preparation of dyeing materials, particularly for textiles. In the recent years, the emphasis on using natural dyes in the tex- tile materials has been increasing because of envi- ronmental issues, to minimize the damage to the environment caused by the production and applica- tion processes used for the synthetic colours and the effluent produced. Kashyap et al. (2016) reported that the natural dyes are considered eco-friendly as these are renewable and biodegradable, are skin friendly and may also provide health benefits to the wearer. Most of the commercial dyers and textile export houses have been exploring the possibilities of using naturally obtained colours for dyeing and printing of different textiles for targeting niche mar- ket. Many studies have been conducted to obtain dyes from different natural sources and on their ap- DOI No.: http://doi.org/10.53550/EEC.2023.v29i03.054