RESUMO
Various azo compounds (Modified dyes) have been synthesised by chemical modification of areca nut extract (epicatechin), a plant-based Polyphenolic compound to get semi-synthetic dyes. Three different primary amines namely p- nitro aniline, p-anisidine and aniline, were diazotized to form their corresponding diazonium salts which were further coupled with an areca nut extract. Preliminary characterization of the areca nut extract and the resultant azo compounds (Modified dyes) was carried out in terms of melting point, solubility tests, thin layer chromatography, UV-Visible and FTIR spectroscopy. These modified dyes were further applied on polyester and nylon fabrics and % dye exhaustion was evaluated. Dyed fabrics were further tested for their fastness properties such as wash fastness, rubbing fastness, light fastness and sublimation fastness. The results of the fastness tests indicate that, all the three modified dyes have good dyeability for polyester and nylon fabrics. The dyed fabrics were also tested for ultraviolet protection factor which showed very good ultraviolet protection.
RESUMO
We have described a novel red biochrome, 514 Da in size, produced by solid-state cultivation of a bacterial isolate obtained from garden soil. The growth requirements of the isolate, the chemical characteristics of the biochrome produced, and the application of the biochrome in dying of silk, wool, and cotton fabrics have been studied. The biochrome obtained after 52 h of incubation and having a λ (max) of 535 nm was used for dyeing the fabrics. We found that silk, wool, and cotton fabrics dyed with this new natural red compound have high color strength values and dye uptake along with good color fastness as well as antibacterial activity.
