Study of a natural dye solubilisation in o/w microemulsions and its dyeing behaviour

The manufacture of synthetic dyes involves many non eco-friendly chemical procedures. For this reason, the application of natural dyes in textile dyeing is being explored worldwide. The dye exhaustion, fixation and levelness of dyeing depends on several factors such as the properties of fibres, the molecular structure of dyes, and the medium of the dyebath. The solubilisation of insoluble natural dyes in colloidal systems like microemulsions and its influence on dye exhaustion and fixation are becoming important in this connection. In the present investigation, the phase behaviour of water/non-ionic surfactant/polar oil system was studied and the microemulsion regions were identified. A water insoluble natural dye, C.I. Natural Orange 2, was then solubilised in selected microemulsions and its ability to dye wool was studied. The mechanism involved in the dye migration from the oil-swollen micelles to the fibre surface was also investigated.