No abstract

The application of natural dyes is increasing each year due to their environmental friendliness and easy application on cellulose fibers. In this study, the natural dye from the Mexican marigold flower was extracted using a Soxhlet extraction apparatus. The extracted natural dye was applied on lyocell fabric with five different metallic salts using pre-mordanting and post-mordanting methods. It was observed that different color shade depth was achieved with different fixing agents. The color shade depth (K/S) washing fastness, light fastness, rubbing fastness, perspiration, and Fourier transform infrared (FTIR) test results of all dyed samples were excellent in both pre- and post-mordanting methods. There was no significant difference in the results between post- and pre-mordanting fixation methods. However, the results showed that mordant ferrous sulfate had higher K/S value as compared to all other mordants. The dye extracted from marigold flower showed good dyeing efficiency with mordant to excellent colorfastness tests. FTIR results showed that there was no structural change in lyocell fabrics, before and after dyeing processes. Thus, a natural dye extracted from marigold flower has shown good colorfastness properties without damaging its fiber structure.

The usage of natural dyes for coloration has attained attention in recent years due to their ecofriendly environment. Therefore, in this study, orange peel solvent extract is used as a natural dye for coloring Tencel fabric samples. Pre-mordanting and post-mordanting methods were accomplished with two different mordants, i.e. ferrous sulfate and copper sulfate. The dyeing shade effects were retrieved through colorfastness properties according to the ISO standardizations. The results revealed that the best color shade ([Formula: see text]/[Formula: see text]: 4.56) was achieved using mordant ferrous sulfate through the post-mordanting method. The effect of lightfastness on all dyed Tencel fabric samples was observed good (3–4) in both mordanting methods. However, mordant ferrous sulfate showed better lightfastness (4) than copper sulfate (3–3.5) through both mordanting methods. Comparatively, in the rubbing fastness, copper sulfate has superior results in both mordanting methods. The ferrous and copper sulfates in both mordanting methods have similar tests results (4.5) of washing fastness, acidic and alkaline perspiration. Furthermore, the FTIR test substantiated that not any structural change occurred through orange peel dyed Tencel fabric samples through both methods. TGA observed samples were relatively stable up to 300∘C temperature. Overall, the best results of colorfastness for Tencel fabric samples were obtained with ferrous sulfate mordant through the post-mordanting extraction method.