Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
177219 | Dyes and Pigments | 2011 | 10 Pages |
Dyeings on cotton obtained using three commercial bifunctional reactive dyes were subjected to a standard, five-stage method which employed a proprietary wash-off agent as well as a three stage, chemical-free wash-off process. Dyeings obtained using both wash-off methods were of the same colour and displayed similar levels of fastness to repeated washing at 60 °C. Lowering the number of wash-off stages from five to three and replacing the wash-off agent with 98 °C water rinses reduced considerably, both the COD and, especially, BOD5 compared with the standard wash-off method, with no increase in COD/BOD5 ratio. The three-bath wash-off method therefore offers potential savings in water usage, compared to the standard method and also eliminates the need for chemicals to be employed in wash-off.