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Tamarind seed coat tannin was extracted and its tannin class was determined. The extracted tannin was employed as a natural mordant alone and in combination with metal mordant namely copper sulphate for cotton, wool and silk fabrics and dyed using natural dyes namely turmeric and pomegranate rind. The colour strength, colour coordinates, wash and light fastness were evaluated and compared for all the three fabrics with and without mordanting. The pre-mordanted fabrics on dyeing gave better colour strength, wash and light fastness than those dyeing obtained without mordanting. The total phenolic content of the extract was calculated and minimum inhibition concentration was 1% against both the Staphylococcus aureus and Escherichia coli bacteria. The mordanted and dyed fabrics resulted in good antibacterial activity up to 20 washes, when natural mordant was used along with 0.5% and 1% copper sulphate mordant and dyed with natural dyes.

Although madder (Rubia tinctorum) has been used as a well-known natural textile dye source for dyeing of natural fibers such as wool, silk and cotton, 100 % polyester dyeing with madder is not common. In this study, polyester samples were dyed with madder at different dyeing temperatures, from 60 °C to 130 °C, in company with 7 chemical and 5 natural mordants. Color properties and rub, light and wash fastness performances were investigated. Different shades of orange, brown, pink and reddish green colors were obtained. Dyeing at 130 °C exhibited the highest color yield, the highest chroma and the lowest lightness values. Overall, chemical mordants exhibited higher color yields than natural mordants. High wash fatness, moderate light and rub fastness levels were observed. The potassium bitartrate and gallnut, a natural mordant, exhibited the best results. The madder dyeing of polyester should be carried out at hot temperature conditions, 130 °C, in order to obtain the highest achievable color yield and chroma with the highest light and wash fastness properties. © 2014 The Korean Fiber Society and Springer Science+Business Media Dordrecht.

Ultraviolet radiation (UVR) blocking properties of textiles depend on fibre type, fabric construction and nature of finishing chemicals. Natural dyes can provide vegetable fibres with strong colours if mordants are used. In this study UV protection properties of dyeing extracts from Mediterranean flora ( Helichrysum italicum Roth, Rubia peregrina L., Daphne gnidium L., Lavandula stoechas L., Cynara scolymus L.) were tested in combination with fabrics made of vegetable fibres (cotton and flax) and different types of mordants (potassium alum and chestnuts tannins). Pre- and post-dyeing solutions were analyzed quali-quantitatively by HPLC/DAD/ESI-MS in order to calculate the dye uptake on fabrics during the dyeing process. UVR transmittance of fabrics was measured using a spectrophotometer equipped with an integrating sphere. After the dyeing process only flax fabrics mordanted with alum and dyed with Lavandula and Rubia, and flax fabrics mordanted with tannin and dyed with Rubia and Helychrysum reached the minimum protection level. A very good protection level was reached by flax mordanted with alum and dyed with Helychrysum. Chestnut tannins provided a slight support in phenols uptake for Lavandula and Helichrysum plant dyes with respect to potassium alum, but without an improvement of the fabrics UV protection properties; flax samples dyed with Helichrysum extract showed an improvement in UV protection properties when mordanted with potassium alum instead of tannins. Colour fastness and the persistence of UV protection characteristics were also tested after light/sun exposure and after several washes.