The results show that deep dyeing of high fastness to repeated washing at 60 C and of good dry and moderate wet rub fastness can be obtained on artificial nylon suede. However, research, using a large number of vat dyes, is on-going, to characterise more fully the colorimetric and fastness (e.g. light, perspiration, etc.) properties
of acid leuco dyeing on nylon fibres of varying dtex. In addition, work is in hand to attempt to identify the reasons for the observed differences between the dyeing of polyamide fibres with the acid leuco and the alkali leuco forms of vat dyes.