Use of enzymes and chitosan biopolymer in wool dyeing

Abstract

The importance of bio-processes and mild chemical so-called 'soft chemistry' processes have been increasing of late. Especially for expensive and fashionable material such as wool and silk, the compatibility with the environment and protecting these fibres' natural properties during their treatments have been investigated. In this study, we used proteases of different origins to treat wool-woven fabric. Proteolytic treatments were carried out with various commercial protease preparations such as Perizym AFW, Alcalase 2.5L, Savinase 16L and Papain. After proteolytic treatments, the samples were evaluated with regard to the loss of tensile strength, weight loss, degree of whiteness and alkali solubility. The samples were then dyed with different classes of dyestuffs such as reactive dyes, levelling acid, milling acid and metal complex dyestuffs. The effects of these proteolytic treatments on colour strength and various fastness values were evaluated. Moreover, some samples treated with proteases were then treated with chitosan, a polysaccharide-based cationic biopolymer, and dyed. Next, the effects of the treatment with chitosan on colour strength were determined.