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Which auxiliaries should be used when dyeing reactive dyes
Apr 24, 2018

Because of the different reactive groups in reactive dyes, the best dyeing temperature and dyeing prescription have also been changed.

Reactive dyestuffs are less direct than direct dyes, so the inorganic salts are added to the dyestuffs to improve their directness. They usually use 50 g/L of mirabilite (Na2SO4) to increase or decrease the amount of salt in different depths. In order to achieve the leveling effect, the inorganic salts can be added in batch. As a catalyst for dyestuff and dyestuff, it combines dye molecules with cellulose molecules. Therefore, it is important not that the alkali is the type but the PH average after adding alkali. In general, the pH value of the dye is 11.5, and the pH value of the usual addition of 20g/L soda can reach about 11.5. But there are also some dyeing and finishing enterprises. The use of caustic soda (NaOH), but because of its strong alkali, the pH value adjustment to 11.5 is certain, that is, not easy to control, so the use of less, but if there is a quantitative feeding system can be used.

When the fabric is dyed to prevent the rope from folding, it is very effective to add soft softening agent to the dyed bath. When the water quality of the dyeing water is hard, the metal chelating agent can be added.


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