The importance of temperature control in high temperature dyeing machines
May 20, 2022
When dyeing with a high temperature dyeing machine, it is necessary to correctly control the heating rate. The actual heating rate should be reasonably set according to the levelness of the dyes used, the depth of dyeing, the circulation state of the dye solution and the different dyeing stages. The usual heating rate is 1 ~ 2℃/min. Slow when it shouldn't be fast.
When the dyeing temperature is below 85 ℃, the dye is rarely dyed, and the temperature can be directly heated. 85°C-110°C is the temperature region where the dyeing speed increases rapidly, and it is necessary to strictly control the heating speed below 1.5/min. It can be slightly faster in the range of 115°C-130°C, but the heating rate needs to be controlled at about 2°C/min. The holding time here is for medium-depth colors, light colors can be appropriately shortened, and dark colors can be appropriately extended. The holding time should be appropriate, too short will cause ring dyeing phenomenon, too long will easily produce wool. Generally, it should be controlled within 30-60min.
After dyeing, the temperature should be lowered quickly, because oligomers will be produced during the slow cooling process, and the surface of the residual thread will be tar-like and difficult to remove.