New Azodisperse Dyes with 5-Pyrazolone Ring for Dyeing Polyester Fibres

82-84<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"="">The dyeing performance of some4-arylhydrazono-1-hydroxymethyl-3-methyl-2-pyrazolin-5-ones on polyester fibres has. It is observed that these dyes have good affinity for polyester fibres, whereas polyamide and triacetate fibres are only slightly stained. The maximum exhaustion of the dye bath takes place at 100°C after 90 min. The fastness properties of the dyes on polyester fibres are compared with respect to the position and the nature of the substituent.