Dyeing of polyamide fibre with cochineal natural dye

Abstract

Purpose The aim of the paper was to study the effects of mordanting methods on the absorption behaviour of cochineal natural dye on polyamide fibres. Design/methodology/approach Iron sulphate and aluminium potassium sulphate salts were used as mordanting agents, and bottom mordanting, meta-mordanting and after mordanting methods were applied in the dyeing of polyamide samples with the cochineal natural dye. Colourimetric evaluations were carried out, and the principal component analysis was used to investigate the spectrophotometric properties of the dyed samples. Fastness properties of the dyed samples were also assessed. Findings The obtained results indicate that the method of mordanting has a great effect on the obtained shades, absorption behaviour and fastness properties. Based on the results, it was concluded that polyamide fabrics could be successfully dyed with cochineal and combination of dyeing with different mordanting methods, and different mordanting agents would develop the range of obtainable shades. Originality/value The textile and apparel industries have been widely criticised for their role in polluting the environment. So, the use of synthetic dyes has been limited and the use of natural dyes has increased. The literature survey indicates that there have been relatively few works investigating the dyeing of polyamide with cochineal natural dye. This research studies the effects of mordanting methods and mordant types on colourimetric and fastness properties of cochineal-dyed polyamide samples.