RESUMO
In the present study, cotton, silk and polyester yarns were dyed with the aqueous extracts of natural dyes from the pink leaves of Cordyline fruticosa and red sepals of Mussaenda erythrophylla. The dyeing was performed with mordants (Alum, Acetic acid, Copper sulphate and Lemon juice) and without mordant. UV-visible spectral analysis of natural dyes was determined. The selected dyed samples were assessed in terms of dye absorption percentage (E%), colour values (CIELAB), colour strength (K/S) and fastness properties. Various shades of ash-green and pink colours were obtained from the aqueous extracts of C. fruticosa leaves and M. erythrophylla sepals. Fastness results showed good to very good grades. It was observed that multiple colours were produced with different mordants from a single source; therefore, the dyes extracted from the above plants are polygenetic in nature.
Assuntos
Cordyline , Rubiaceae , Corantes/química , Seda , TêxteisRESUMO
In the present study, an attempt had been made to explore the potential of natural colourants and its application in the textile industry. Natural colorants extracted from the sepals of Mussaenda hybrid, fruits of Carissa carandas and Syzygium cumini were applied on cotton, silk and polyester yarns accompanied with mordants (Alum, Acetic acid, Copper sulphate and Lemon juice) and without mordant, using an aqueous method. UV-Vis spectra of different natural dyes were determined. Percent absorption, colour co-ordinates values (CIELab), colour strength (K/S) values and fastness properties of the selected dyed yarns were tested. Different shades of yellow, pink and purple were obtained from the aqueous extracts of Mussaenda hybrid, Carissa carandas and Syzygium cumini. K/S values were enhanced with the addition of mordants. Fastness results of the selected dyed yarns showed good grades. The present study demonstrated that the above plants could be a promising source of natural colourants.
