When the yarn dyeing machine is produced under high temperature and high pressure conditions, when the polyester is dyed with disperse dye, the molecular structure of the polyester is closely arranged, the fiber pores are extremely small, and the dye molecules are difficult to enter the fiber core layer, so the high temperature and high pressure dyeing is used instead of the closed type. The machine promotes fiber expansion by high temperature to facilitate dyeing, and it is also necessary to extend the dyeing time to overcome the resistance of the fiber to dye adsorption. In addition, efforts must be made to improve the fineness of the dye particles.
For yarn dyeing machines, high temperature and high pressure processes are widely used, usually under closed conditions, with steam heating and pressurization to a temperature of 130 ° C for dyeing. The pH value during dyeing is particularly important. In addition, the dyeing temperature, time and water quality have a great influence on the dyeing quality of polyester. Usually, the pH in the dye bath of high temperature and high pressure dyeing is controlled in the weak acid range of 5-6, and an appropriate amount of diffusing agent is added in the dyebath.
In short, during the use of the yarn dyeing machine, since the dye liquor circulates in the thick layer of the yarn, if the water quality is not good, not only the color is light, but also the dye is precipitated, filtered onto the yarn, and dyed. spot. Therefore, soft water should be used when dyeing yarn at high temperature and high pressure to ensure the stability of dyeing quality.www.textiledyeingmachines.com