Study On The Dyeing Process Of Hydrophobic Fiber With Microencapsulated Disperse Dyes

Hydrophobic fibers play an important role in textile and some high-tech area due to their outstanding utilitiy properties, e.g. resistance to cauterization and mildew, high wet strength, anti-moth and low hygroscopicity. Whereas the traditional dyeing using disperse dyes of hydrophobic fiber are those processes which are carried out by auxiliaries solubilization. Furthermore, subsequent reductive cleaning, soaping & rinsing bring about heavy burthen to environment.According to literatures, the dyeing process of hydrophobic fiber using microencapsulated disperse dyes is characterized with no auxiliaries solubilization, less unfixed dyes on fiber surface, low dyeing waste water chromaticity, leaving out reductive cleaning, economizing dyeing time, energy conservation and emission reduction.In this paper, disperse dyes microcapsules were prepared by means of in-situ polymerization. Different microcapsules were obtained by different use level of system regulator PDA and under different emulsion time. The mean size and distribution of microcapsules were tested by Laser Granularity Analyzer and their surface topography were observed by Scan Electron Microscope. PET fabrics were dyed using disper dyes microcapsules with infrared high temperature high pressure dyeing machine. Relating dyeing behaviors were tested by datacolor, soaping and dry/wet rub machine. The results show that the disperse dyes microcapsules prepared by PDA whose dosage from 2% to 16% are prone to sieve and appear powdery after drying. The disperse dyes microcapsules prepared by 8% PDA with 10min emulsion time exhibit better dyeing behaviors to PET fabric, better encapsulated and excellent thermal stability.Integrating the characteristics of the traditional disperse dyes of hydrophobic fiber and the polyester dyeing with disperse dyes microcapsules under high temperature high pressure condition without auxiliary reagent, the optimum dyeing parameters were established by investigating of the bath ratio, dyeing temperature, heat preservation time and the pH of dying bath. Results show that the dyeing process of nylon 6 using microencapsulated disperse dyes possess better level dyeing at 1:30 bath ratio, 100℃dyeing temperature, and 40 min heat preservation time. During the process of dyeing, there is had better preserving heat at 80℃, falling the speed of raise temperature simultaneity. When 100℃, preserve temperature for 40 min. Then insulate disperse dyes microcapsules, continue to dye for 20 min. High quality color fastness fabric can be obtained by this way. The dyeing process of PTT fibers using microencapsulated disperse dyes take on better level dyeing at pH 7, 100℃dyeing temperature, 40 min heat preservation time. During the process of dyeing, there is had better preserving heat at 60℃, and reducing the speed of raise temperature. As far as the dyeing process of ultra-fine fiber synthetic leather is concerned, the optimization dyeing parameters are pH 7, 120℃dyeing temperature, 40 min heat preservation time. During the process of dyeing, there is had better preserving heat at 80℃, and debase the speed of raise temperature.Compared with the traditional dyeing process, the results of disperse dye microcapsules dyeing process show without dispersant and level dyeing reagent, the developed dyeing technology which leaving out reductive cleaning can impart the hydrophobic fiber deeper color and outstanding color fastness, including the dry/wet rub fastness, staining fastness and colour fading grade. Moreover, the chromaticity of dyeing wastewater is reduced obviously after filtrating microcapsules.In the interest of ensuring quality of dyeing samples and avoiding additional device, above discussed process of hydrophobic fiber using microencapsulated disperse dyes is easy to implement, less investment, energy conservation and emission reduction.