Study On Union-Color Of One-Bath And One-Stage Dyeing Of Silk/Cotton Fabrics

Cotton/silk(blended or woven) fabrics are featured by bright luster,good moisture absorption,ventilation,flexibility and drape,which is better than pure silk and cotton fabric,but the color difference of cotton/silk fabrics is big.In order to improve the homochromatic level of the silk/cotton fabrics,two-bath and two-stage dyeing of silk/cotton with reactive dyes and acid dyes is mainly used in industry now,due to cumbersome production process,plant dyeing processing time of up to 6-8 hours,the consumption of energy and water is large.One-bath and one-step dyeing process can save energy,reduce emission,and improve production efficiency.People have been trying to use one-bath and one-step dyeing of cotton/silk fabrics with reactive.But the direct and the dyeing rate of reactive dyes with the different structures onto cotton and silk are different at different process parameters,which makes the color shading of one-bath and one-stage dyeing of silk/cotton with reactive dyes big,process parameters difficult to control.The main target of this paper is developing the homochromatic properties of one-bath and one-step dyeing of silk/cotton fabrics by chosing suitable bi-functional reactive dyes and studying dyeing conditions.Under normal circumstances(weak acid),cotton / silk fabrics is dyeing in light,the color yield of the silk is higher than cotton.For this case,this paper utilized high activity of dyes,the direct on cotton is higher or relatively closer than silk at lower temperatures.This minimize the color shading of cotton/silk fabrics on dyeing stage.Several important factors influencing the homochromatic level of the silk/cotton fabrics were also researched,such as dyeing temperature,pH value,salt and base dosages,fixation time and temperature.The homochromatic level of silk/cotton fabrics and the principle of dyeing process was discussed by using K/S value,dyeing percentage,dye fixation and the value of the same color balance.Industrialized technology preparation of union-color of one-bath and one-step dyeing were gained finally by many experiments which simulated plant condition.Cotton/silk(mass percentage:80/20) blended yarn which was dyed with this process had good levelness,dye penetration and the union color,the same color balance values(Q) with an absolute deviation of around 0.3,and soaping fastness, alkaline perspiration fastness,rubbing fastness and light fastness were about 4. In addition,the paper also used buffering agent to improve union-color of one-bath and one-step dyeing of the cotton/silk fabrics.By choosing the suitable buffering agent and evaluating the dyeing percentage,dye fixation,K/S value and the value of the same color balance,we found that buffering agent lyogen AB could improve union-color of one-bath and one-step dyeing of the cotton/silk blended fabrics by decreasing the dyeing rate of dyes onto silk efficiently.This method can broaden range of options of reactive dyes which wre used in one-bath and one-step dyeing of silk/cotton fabrics.At the same time,this paper has obtained curve function(Y) by drawing the corresponding curves of K/S value and dyeing percentage(o.w.f) of dyeing fabrics. when the K/S value of the cotton and silk fabrics is same,the dyeing percentage(o.w.f) of silk is higher than cotton’s by calculating and analyzing the function(Y).This function can illustrate the influence of dyeing percentage on union-color of one-bath and one-step dyeing of the cotton/silk fabrics.This method needs further theoretical research and confirmation.