Evaluation of Natural Dyeing of Leather with Rubia tinctorum Extract

Abstract

The aspect o f producing leather and textile products without impacting on the ecological balance, affecting both human and environmental health, is an important focal point to be pursued. Therefore, to address some o f these issues a study was conducted to evaluate the efficiency o f dyeing leather with madder, which is a 100% natural dyestuff from the extract o f Rubia tinctorum and ascertain its friendly attributes to the environment. Treatment designs in the study included pre and post mordanting methods which were applied to selected types o f leather and subsequently subjected to three different mordants: potassium aluminium sulphate [K A h S O ^ .U H ^O ] , copper sulphate [CuSO^SH^O] and ferro sulphate [FeSO4.7H2O]. This approach was done to potentially obtain different colors and improve color fastnesses. In this study, the investigation was based on two primary source o f tanned material, chrome and vegetable tanned leathers. Color measurements o f the dyed leathers were carried out using a M inolta CM-508d brand spectrophotometer. O n the other hand, dyestuff exhaustions were determined using a Shimadzu UV-1601 PC UV-Visible spectrophotometer. O n the finished leather products, parameters such as color fastness to rubbing was determined with, the TS EN ISO 11640, color fastness to perspiration with, the TS EN ISO 11641, and color fastness to light with, the ISO 10S-B02 standard method. Moreover these parameters were comparatively analyzed and reported. The results eventually indicated that the obtained color and color fastness values varied according to; the type o f tanning method, mordanting method, and mordant type. Most o f the result values obtained were generally at satisfactory levels which were between 3/4 and S fastness values. Different extraction methods, different mordants, and mordanting methods to be carried out in future are suggested so as to optimize the results o f the current study.