棉针织物和纤维的活性染料无盐染色

Salt-free dyeing of cotton knitted fabrics and fibers using reactive dyes

无盐染色是减少废水中盐含量,提高废水回用率,减少废水排放的重要途径。在不进行前处理的条件下,使用自主开发的活性染料和碱剂对棉针织物和纤维进行低温无盐染色,研究了碱剂用量、染色温度、染料浓度和染色时间等因素对染色效果的影响,测定了染料固色率。结果表明,未经过前处理的棉针织坯布在25℃染色4~10 h,染色效果与经前处理的织物相同。染色后原棉纤维的染料固色率比常规染色工艺高5%以上,其可纺性优于常规染色工艺。扫描电子显微镜图像表明,原棉纤维染色后表面变得洁净光滑,形态结构无明显变化。

Salt-free dyeing is an important way to reduce the salt content and the discharge of waste- water, and to enhance the reuse rate of wastewater. The objective of the present study is to realize salt-free dyeing of un-pretreated cotton knitted fabrics and fibers at low temperature using self-made reactive dyes and alkali agents. The effects of alkali dosage, dye concentration, dyeing temperature and time on dyeing results are investigated. The dye fixation yield is also determined. The results show that the un-pretreated fabrics dyed at 25 ℃ for 4-10 h can reach the same dyeing effect as the pretreated fabrics. The fixation yield of the dyed raw cotton fiber is 5% higher than the cotton fiber dyed with conventional dyeing process. The spinnability of the salt-free-dyed cotton knits is better than the conventional-dyed cotton. The scanning electron microscopy images show that the dyed cotton fibers become cleaner and smoother than the original fibers, and there are no obvious changes in morphology.