The temperature of the HTHP sample dyeing machine is the key factor of dyeing during the operation. It can increase the temperature to a certain extent, and can effectively increase the dyeing rate of the dispersed material, but when the temperature is higher than 130 degrees, most of the dispersion The percentage of dye uptake no longer increased significantly. If the temperature is too high, the polyester ester bond will be hydrolyzed, resulting in a decrease in the elasticity and strength of the fiber, and the color shade is poor. Therefore, the high temperature and high pressure dyeing is generally limited to not more than 145 degrees.
The dyeing temperature of the HTHP sample dyeing machine is generally controlled between 125 and 130 degrees. At this temperature, the dyeing is not only good in leveling property, but also has a high color yield, and the pH value of the dyeing bath is controlled in the weak acid range of 5-6. Inside, most of the disperse dyes are quite stable, so the color is very bright. In order for the dye to be uniformly adsorbed by the polyester, the heating rate must be strictly controlled. When the temperature is raised to the specified temperature, the dyeing should be kept for a period of time to ensure that the dye diffuses and penetrates sufficiently.
The high temperature and high pressure sample dyeing machine is generally 30-60 minutes when it is dyed, the light color can be shorter, and the dark color can be longer. After dyeing, the temperature should not be too fast, otherwise it will affect the hand and cause creases. Many disperse dyes will hydrolyze under high temperature alkaline conditions, so high temperature and high pressure dye baths are suitable for controlling acidic conditions.