摘要

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 degrees C. Lowering the number of wash-off stages from five to three and replacing the wash-off agent with 98 degrees C water rinses reduced considerably, both the COD and, especially, BOD(5) compared with the standard wash-off method, with no increase in COD/BOD(5) 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.

  • 出版日期2011-2