study of raspberry extract applications as textile colorant on natural fibers

The present study deals with the biomordant assisted application of natural extracts obtained from red raspberry (Rubus idaeus L.) fruits onto two different cellulosic supports – flax and bamboo. The study relies on the improvement of multifunctionalities such as colour fastness, washing and rubbing fastness, due to the synergism provided by the co-assistance of both a biomordant, and the complex resulted by inclusion of the pigment molecule, in the cavity of MCT-β-CD; it is well known that natural dye molecule have a good selectivity binding to the hydrophobic monochloro-triazynil-cyclodextrin’s (MCT-β-CD) cavity to form inclusion complexes. An investigation system provided the characterization of the composites: FT-IR spectroscopy stressed the main chemical bonds created between MCT-β-CD as host molecule and guest molecule represented by natural colorant molecule; Brunauer-Emmett-Teller (BET) Surface Area Analysis completes the analysis, proving the positive contribution of MCT-β-cyclodextrin grafting. Dyeing fastness and colour modifications were conclusive for this research. Samples of bamboo knitting are less colorful than those of the flax fabric in terms of high absorption capacity and stability / durability of natural dye applied by inclusion within cyclodextrin’s inner. The results of analysis revealed improvement of washing and rubbing fastness (1-1.5 points). Colour modifications noticed due to the colorant deposition were quantified from up to 3 points.