Azodisperse Dyes with Photochromic Mercury(II)-Dithizonate Moiety for Dyeing Polyester, Nylon and Cellulose Triacetate Fibres

Abstract

<span style="font-size:11.0pt;line-height:115%; font-family:" calibri","sans-serif";mso-ascii-theme-font:minor-latin;mso-fareast-font-family:="" "times="" new="" roman";mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:="" minor-latin;mso-bidi-font-family:"times="" roman";mso-ansi-language:en-us;="" mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">Some 4-{arylazophenyl) mercury(II) dithizonates were synthesized and their dyeing performance on polyester, nylon and cellulose triacetate fibres was assessed. All the dye samples showed moderate to good fastness to light, and very good to excellent fastness to washing, rubbing, perspiration and sublimation. The dyed fibres on exposure to bright sunlight or a light source of suitable wavelength showed a very good Photochromic effect giving various shades. When the fibres were removed from sunlight the colour returned to the original shade. The duration required for this return depended on the intensity of incident light, ambient temperature and the moisture content of fabric. Polyester fibres required a longer duration for attaining the original shade but rapid change was observed by ironing the cloth. The return rate could be increased by keeping nylon fibres in an oven at 80°C for 2-3 min and polyester fibres at 100°C for 2-3 min.</span>