Sustainable dyeing technologies for Polyester

The aim of this paper is to review possible polyester dyeing method technologies in order to reduce the environmental impact of dyeing polyester fibre. It will answer the research question, what are the sustainable alternatives to conventional polyester dyeing process? Currently polyester is dyed using disperse dyes using carrier or HTHP method. Polyester fibre is the most used fibre in the textile industry, due to its physical properties, price, recyclability, and versatility however, 30% of pollutants in textile chemical processing is from dyeing and printing process. Therefore, it is the need of the hour to find sustainable alternatives to conventional polyester dyeing. The paper reviews the following sustainable polyester alternative dyeing methods: Air Dyeing, Supercritical CO2 dyeing, Dope Dyeing and Spray Batch Dyeing. The process of dyeing as well as advantages and disadvantages are reviewed. A few alternatives such as natural dyes and thermosol dyeing is also discussed. A conclusion of each alternative dyeing method is derived from the studied literature, performance as well scope is also discussed. The sustainable polyester dyeing space has received quite a lot of attention in the past few decades. However, it still has immense potential and further investigation is required to solve problems of colourfastness and operational costs.