Reactive Dye Characteristic

Reactive dyes suppliers to introduce the characteristics of Reactive dyes for you

1. Solubility

Reactive dyes have good water solubility.The solubility and the concentration of the prepared dye are related to the bath ratio, the amount of electrolytes added, the dyeing temperature and the amount of urea used.The solubility of reactive dyes is different, applied in printing or pad dyeing reactive dyes, should be selected in the solubility of about 100 g/l variety, the requirements of complete dye dissolution, no turbidity, no color point.Hot water can accelerate the dissolution, urea has a solubilizing effect, salt, such as sodium, sodium powder electrolytes will reduce the solubility of dyes.Alkali should not be added at the same time when the reactive dye is dissolved to prevent hydrolysis of the dye.

2. Diffusivity

Diffusivity refers to the ability of the dye to move into the fiber, and the temperature is conducive to the diffusion of dye molecules.The dye with large diffusion coefficient has high reaction rate and color fixation efficiency, and the degree of evenness and penetration is good.The diffusivity depends on the structure and size of the dye.On the fiber affinity of the dye by the fiber adsorption force is strong, diffusion is difficult, usually by increasing the temperature to accelerate the dye diffusion.The diffusion coefficient of dye decreases when electrolyte is added into the dye solution.

3. Directness

Directness refers to the ability of reactive dyes to be absorbed by fibers in the dye solution.The solubility of reactive dyes is often low direct, continuous pad dyeing and printing should be chosen low direct varieties.For dyeing equipment with large bath ratio, such as rope-like dyeing and Hank dyeing, high directness dyes should be preferred.Rolling roll (cold rolling) dyeing method, the dye is transferred to the fiber through the dip rolling, also with a slightly lower directness of the dye is easy to be evenly dyed, before and after the color difference is less, hydrolysis dye is easy to wash.

4. Reactivity

The reactivity of reactive dyeing usually refers to the dye and cellulose hydroxy reaction ability strong and the weak, strong Reactive dye at room temperature, under the condition of weak base namely fixation can be performed, but the reaction of the dye stability is relatively poor, easy to hydrolysis lose Dyeing ability.Reactive dyes need to bond with cellulose at a higher temperature, or use a strong alkali to activate the hydroxyl group of the fiber yarn, so that the dye reaction is fixed to the fiber.

Hydro Peroxide Stabilizer LH-P1510

Development of dyes

In order to meet the needs of dyeing, new dyes have been constantly emerging in recent years. The development of new dyes is mainly to meet the following requirements:

(1) replace banned dyes and develop environmentally friendly dyes;

(2) adapt to the needs of new fibers and multi-component textile dyeing;

(3) adapt to the needs of new technology and new equipment processing;

(4) to meet the needs of efficient, water-saving and energy-saving processing.

The development of reactive dyes includes new chromophores, reactive groups and their combinations in molecules, and the mixing of ligands and different dyes. In addition, the post-processing of commercial dyes has been greatly improved. The performance of new reactive dyes is mainly shown in:

(1) high color intensity, high directness and fixation;

(2) high fastness, including fastness to sun, friction, sweat, chlorine and soaping, etc.;

(3) low salt, low alkali or neutral staining and fixation;

(4) environmentally friendly, free of harmful aromatic amines, heavy metals, formaldehyde and other substances;

(5) good levelness, reproducibility and compatibility.