Electrochemical reduction processes in indigo dyeing

The application of indirect electrolysis as a reduction technique in indigo dyeing is described. Various reversible redox systems were tested to determine whether they are suitable for indigo dyeing. The results of the dyeing trials confirm that the process engineering involved can be applied to the production of denim. The new process offers environmental benefits and offers the prospects of improved process stability, because the reduction state in the dyebath can be readily monitored by measuring reduction potential.