One-Bath Dyeing Of Polyester/Cotton Blends With Disperse And Reactive Dyes

One-bath dyeing of polyester/cotton blends is performed in one-bath process with disperse dyes, reactive dyes and other related auxiliaries. With temperature increasing, polyester and cotton components are dyed by the disperse dyes and reactive dyes separately. Comparing to the conventional two-bath method, the one-bath dyeing process has many advantages, such as short dyeing time, low energy and water consumption. In addition, this dye system meet the requirements of sustainable development, namely energy saving, emission reduction, and low carbon conception. Therefore, it is very important to research one-bath dyeing.The suitable reactive dyes and disperse dyes were screened out. According to dyeing factors, the practical dyeing processes are determine, which will reduce the production costs and achieve the goals of energy-saving and emission-reduction and the technology progress of finishing &dyeing industry.First of all, through the orthogonal experiment, different structure reactive dyes such as monochlorotriazine, vinyl sulfone, double active groups with monochlorotriazine and vinyl sulfone, and bichlorotriazine were chosen to dye under the high temperature conditions. According to the K/S%, the dye absorbing rate and resistance to elevated temperatures, the dyes with bichlorotrazine groups are better than other reactive dyes. Secondly, The salt-tolerant and the alkali-tolerant properties are tested with the ALK disperse dyes producted by Zhejiang Longsheng company. Comparing the dyeing results, the K/S% can reach 80% when the concentration of Na2SO4 is 70g/L; and the K/S% is 85% when the concentration of Na2CO3, which identified that the disperse dyes can dye under the high alkali and high salt conditions because their good resistant to salts and alkalis. Therefore, the bichlorotriazine reactive dyes and the ALK disperse dyes were chosen to research the one-bath dyeing process.Polyester fabric and cotton fabric were dyed under the same dyeing procedures. The result revealed that the red series and the blue series can also have a high dye fixed rate and K/S% when the temperature is about 115-130℃, the concentration of Na2SO4 is about 40-60g/L, the concentration of Na2CO3 is 0-10g/L, the dyeing time is 30-60min. But the results is not suitable for the yellow series.Besides, the one-bath dyeing of polyester/cotton (65/35) blends fabric were investigated in this paper by single factor and orthogonal experiments. The various color fastness such as light fastness, water and soaping fastness, rubbing fastness and chlorine fastness were estimated. The best dyeing processes were determined. The blue is dyed at 125℃,45min in 2g/L soda ash 50g/L Na2SO4; the red is dyed at 125℃,50min in 2g/L soda ash and 60g/LNa2SO4.Changing the concentration of dyes, the results of pale and medium depths of shade dyed by all-in process were excellent. The bursting strength is better compare the one-bath process with the two-bath process, which reduced the damage of the fabrics. But the heavy depths of shade cannot be obtained because of the low color fastness especially the wet rubbing fastness and soap fastness. The reasons is that the high concentration of reactive dyes and disperse dyes were stained each other. Using the auxiliariese.g.DM-2588 and DM-1510 can improve the color fastness, which will obtain the results of dyeing in two-bath process.