Polyester is one of the most important varieties of synthetic fiber, with a lot of excellent performance like durable, good elasticity, easy to deformation, corrosion resistance, insulation, crisp, easy to wash and quick drying, while the price low. At present, polyester dye is mainly disperse dye. With the emergence of polyester fibers, dispersed dye has developed rapidly, becoming a large category of products and the only one suitable polyester dye.
For better and high quality of polyester production, the auxiliaries for polyester are necessary in the dyeing, printing and finishing processes. The chemicals for polyester include expanding agent, fixing agent for polyester, oligomer inhibitor, polyester brewing agent, dyeing acid, oil removing and high temperature leveling agent, reduction cleaning powder, acid reduction cleaning powder, acid reductive cleaning agent, high temperature leveling agent, heat sublimation fastness improving agent and dyeing accelerator etc.
In general, the slow function of leveling agent is the key for leveling dyeing. However, for the polyester fiber using polyester dye, the leveling agent also needs to have strong migration performance. No matter in the process of grinding of polyester dye or in the process of dyeing polyester, you need to add a lot of dispersant to disperse the polyester dye. In order to remove the floating color caused by disperse dye, polyester dyeing will be followed by the cleaning process which uses mild reduction clearing agent for polyester, replacement of sodium hydrosulfite.
In order to achieve a better dyeing effect, polyester dyeing usually need to add a certain amount of polyester auxiliaries, whose functions are multiple in the actual process, such as:
1. These polyester auxiliaries can appropriately increase the solubility of disperse dyes;
2. Promote the adsorption of disperse dyes on the fiber surface;
3. Plasticized the fiber or increase Swelling degree to speed up the diffusion of disperse dyes in the fiber;
4. Improve the dispersion stability of the dye.
In general, polyester auxiliaries plays a very important role on the polyester fiber dyeing .