Tanning materials used for production of leathers may vary according to the properties required and the field of use. Since different tanning materials react with different reactive groups of the collagen, this results changes in the reactive groups available for the chemicals that will be used in further processes. Simple acid dyes are the most common used dyestuffs in the leather industry, generally without considering the type of tanning. Starting from this point, it has been investigated the consumption and fastness properties of the simple acid dyes on the leathers tanned with various tanning materials. Chromium and aluminium from mineral tanning materials; tara, gambier and valonea from vegetable ones were selected for the trials. Simple acid dyes gave good consumption and fastness values for dyeing of mineral tanned leathers however the values for vegetable tanned leathers were relatively bad. 1:1 metal complex dyes were tried as an alternative, and the results of the trials were rather good for both the mineral and vegetable tanned leathers.
