About the cause of the color difference problem in dyeing

In the textile industry, dyelot chromatism refers to the color difference of the same kind of grey cloth dyed with different dyeing vats of the same color. This is a widespread problem. The cylinder difference is also the color difference between the first cylinder and the next cylinder of the dyed cloth, and the color difference generally refers to the color difference of the same dyed cloth, including the cylinder difference and the color difference in the same cylinder.

Effect of the remaining dye solution in the dye vat
Dyeing vat dyeing causes vat difference. It mainly refers to the presence of a small amount of residual liquid after dyeing in the previous tank, and various dyes are present in the residual liquid. Because the dyeing rate of each dye is different, the error is large and the cylinder difference is easy to produce due to the large number of dyes added in the dyeing process of the cylinder.
The effect of temperature
Like other dye dyeing, under the condition that the dyeing can reach the process equilibrium, the dyeing percentage increases with the decrease of temperature, the temperature is 60 degrees during dyeing, and the temperature is lower than 60 degrees, which affects the color rate and makes the fiber color rate too low; Higher than 60 degrees, the dye is easy to hydrolyze, which affects the dyeing rate, and the color yield of the fiber is low.
Effect of staining time
It is easy to color for a long time, and the color will be deeper, so the length of time controlled by the cylinder stopper dyeing will produce a cylinder difference.
Effects of electrolytes
The reactive dye molecule is relatively small, the diffusion performance is good, and the leveling effect is good, so a large amount of electrolyte can be added to promote dyeing during dyeing, which can effectively increase the percentage of dyeing. However, too much electrolyte can also cause staining instability.
The effects of alkaline agents
Reactive dyes in alkaline media, bonded and fixed with cellulose molecules at the same time, dyes will also be hydrolyzed in alkaline, although the reaction speed of dyes and fibers is fast, but if the treatment is not good, the amount of dye hydrolysis will increase. Therefore, in the case of ensuring good color fixation, the pH value should be as low as possible, and it is generally appropriate to control it at 10-11