How to prevent the occurrence of color dots in the process of color paste configuration
In the configuration of color paste, because to mix with a variety of dyes, and the color of the dyes configured are different. For different dyes, the amount of dispersant used is also different. When modulating color paste, it should be strictly operated according to the nature of dyestuff and dissolution conditions, and according to the relevant preparation requirements.
When preparing dyestuffs with low solubility, other co-solvents should be used to assist in addition to strict temperature control. Under high speed stirring, the dyestuff will be fully dissolved. In this process, the selection and dosage of co-solvents are crucial.
For example, the amount of urea used in the dissolution of reactive brilliant blue K-3R should be substantially increased than the theoretical amount, that is, the amount of dyestuff and urea added at 1:3 is more suitable for paper collection, and can be kept for about 5h without dye particles precipitated after making the color paste. Such as the use of dissolved salt B as a co-solvent, the dye dissolved more fully than urea, and placed for more than 5h no dye particles precipitation, to overcome the effect of color point is particularly significant, but the resulting color than the normal shallow about 2 into.
When the color paste preparation is basically formed, it is necessary to add the last alkali agent. The amount of this alkali agent in the preparation should not exceed 20g/L at most, and the temperature of modulation should be controlled at about 45~50℃, using these two points can also effectively prevent the occurrence of color spots.
