Dyeing of silk with natural dyes (English)

In the present study an attempt has been made to explore the possibilities of extracting dyes from different parts of plants and to optimize various dyeing variables for dyeing of silk in a wide range of colors by using metallic mordants. The following natural dyes were selected for the study: Jatropha integerrima (flowers), Lantana camara (flowers), Hamelia patens (leaves), Euphorbia pulcherrima (leaves), Kilmora - Berberis vulgaris (roots) and Walnut - Juglans regia (barks). The maximum percent absorption of Jatropha, Lantana, Hamelia and Euphorbia dye was achieved in acidic extraction media, for Kilmora and Walnut dye in alkaline media. A concentration of 1% extraction media showed best results for all the dyes except for Kilmora, for which the maximum percent absorption was found to be with 0.8%. The optimum extraction time for Lantana, Euphorbia and Walnut dye was 90 min, for Jatropha, Hamelia and Kilmora dye 60 min. Optimum dye concentration for all dyes was between 3 and 7 g/100 ml water. 30 min dyeing time gave best results for Jatropha and Hamelia, 45 min for Kilmora and Walnut, 60 min for Euphorbia and 75 min for Lantana. A mordant concentration of 5% of alum was best for Jatropha, Hamelia and Kilmora, 10% for Lantana and Walnut and 15% for Euphorbia. In case of CuSO4 mordant, 2% concentration was recorded as best for all the dye sources except Kilmora, for which 3% showed the best results. 1% concentration of ferrous sulphate mordant was best for Jatropha and Hamelia, 2% for Kilmora and Walnut, 3% for Euphorbia and 4% for Lantana. The optimum mordanting method for all three mordants was found to be pre-mordanting for Jatropha dye, simultaneous for Hamelia dye and post-mordanting for Lantana dye. In the case of Kilmora and Walnut dye the mordanting method depends on the mordants. The colours obtained are different pink shades for Jatropha, gray and green shades for Lantana, pink and peach shades for Hamelia, rose, brown and henna shades for Euphorbia, yellow and green shades for Kilmora and beige, brown and black shades for Walnut.