Novel dyeing process using H_2O_2 oxidized indigo naturalis

Traditional air oxidation of the plant dye indigo naturalis have hindered its modern production.For this reason,this article studied dyeing wool fabrics with indigo naturalis which contained natural indigo and oxidized it with hydrogen peroxide in replace of the air,to explore the possibility of industrial scale dyeing using indigo naturalis.The effects of hydrogen peroxide′s concentration,oxidative temperature,pH value and time on the result of dyeing were studied.The oxidative effect of hydrogen peroxide is compared with that of the air.The results indicated that the K/S value,color fastness and reproducibility of the dyed fabric employing hydrogen peroxide oxidation were better.Compared to the traditional air oxidation,hydrogen peroxide oxidation is easier to control and more applicable to modern production.