Dyeing silk and cotton fabrics using natural blackcurrants

Silk and cotton fabrics were dyed using the extract from blackcurrants, and the properties of the dyed fabrics were investigated. The natural dyes present in the blackcurrants were identified as four types of anthocyanins, i.e. delphinidin-3-glucoside, delphinidin-3-rutinoside, cyanidin-3-glucoside, and cyanidin-3-rutinoside. The colors of the fabrics dyed with and without five types of mordants, including Mg ²⁺ , Ca ²⁺ , Al ³⁺ , Fe ³⁺ , and Cu ²⁺ , were measured and expressed according to the CIELAB color system, Δ E* value, and K/ S value. The affinity of the extracted dye for the silk fabric was higher compared with that for the cotton fabric. The crystallinity of silk was lower than that of cotton. The fabrics dyed with blackcurrants had UV shielding ability, especially at 330–400 nm, and antibacterial properties. Although color fastness to light and washing (color change) was not sufficient, treatment with Mg ²⁺ , Fe ³⁺ , and Cu ²⁺ mordants could enhance the color fastness.