Dope Dyed dissolved in water, the molecule contains sulfonic acid or carboxyl, can be directly under the neutral conditions of cellulose fibers (weak acid conditions on the dye protein fibers). It is used for cellulose fiber, paper, leather, protein fiber and cotton and so on.
Dyeing on the dye into the pigment anion, and negatively charged cellulose surface repulsion, salt can reduce the repulsion, the effect of different effects of different dyes. For evenly dope dyed, the temperature is high and the uptake rate drops. For the temperature effect of dope dyed, increasing the temperature is conducive to dye diffusion, increasing the rate of dye uptake and the percentage of dye uptake.
Only a single dye molecule can diffuse into the fiber. There is a rapid equilibrium between the individual molecules and the collective in the solution. The aggregation process is slightly exothermic. As the dye dye temperature increases, the aggregates gradually dissipate (endothermic), so that more individual molecules can penetrate like fibers. The uptake rate is then increased with increasing temperature. Finally, if the dyeing temperature continues to increase, and the aggregation is no longer obvious, the final dyeing will begin to decline with the increase in temperature.
Dope dyed products, there are a certain amount of yuan and other thin powder to adjust the concentration of dyes. Cellulose fibers are stained in a neutral environment containing metamromole or salt. Dyeing, the first dye with a small amount of cold water into a slurry, can add a small amount of wetting agent. And then continue to stir, add hot water to dye the dye fully, the amount of dye with the color density and bath ratio may be.
For quiet applications, UV consumption becomes important and under intensity, cooling wear and amplitude become important. Nylon has a greater adaptability and comfort than the wear of the background, its high degree of amplitude and absorption background authoritative is considered to be the most suitable for decorative absolutely and dope dyed polyester yarn the best.