Abstract:

In view of the problem of low production efficiency, uneven dyeing in cold pad-batch dyeing process, the cotton fabrics and Tencel/cotton fabrics were dyed with reactive dyes salt-free continuous pad-steam dyeing process. The stability of padding solutions were measured using AGS analyzer. The special alkali was used in pad-steam dyeing with the SNE reactive dyes, and the dyeing effect was compared with that of pad-batch dyeing. The results show that the stability and diffusion properties of dye solutions were affected by alkali composition and time. When the dyeing solution with mixed alkali is placed for 10 min, the stability index is 0.72, which are 2.6 and 2.1 times higher than that of dye liquors with special alkali and Selilao. The special alkali and Selilao can improve the diffusion performance of padding solutions. The Integ values of the dyed cotton fabrics (army blue, coffee) obtained from the salt-free continuous pad-steam dyeing process are 2.9 and 2.7 times higher than that of dyed fabrics using cold pad-batch dyeing process, respectively. The color fastness of dyed fabrics is more than 3 grades, which is in accordance with the production requirements. The salt-free continuous pad-steam dyeing process can also be used in reactive dyeing for Tencel/cotton union fabrics with the advanages of high productivity and darker color depth.

Key words: reactive dye, cold pad-batch dyeing, salt-free dyeing, Integ value, color fastness