First, the effect of thermal migration of disperse dyes […]
First, the effect of thermal migration of disperse dyes:
1. The shade of the dyed object changes;
2. The rubbing fastness decreases;
3. The fastness to washing and perspiration decreases;
4. Fastness to sunlight decreases;
5. The fastness of dry cleaning decreases;
6. When ironing, it causes staining of other fabrics.
Second, the reasons for thermal migration of disperse dyes:
Thermal migration is a redistribution phenomenon of disperse dyes in two-phase solution (fibers and additives). Under high temperature or long-term storage conditions, the dye is dissolved by the additives remaining in the outer layer of the fiber and moves the dye Fiber surface
Fiber residue additives generally come from:
1. Oil agents and antistatic agents added during spinning or weaving;
2. Various auxiliaries added during dyeing and finishing, such as refining agents, softeners, etc .; nonionic surfactant residues are more likely to cause thermal migration of dyes;
3. The sublimation fastness of disperse dyes is not absolutely related to thermal migration;
4. Disperse dyes with different structures have different thermal migration under the same conditions.
Third, the prevention of thermal migration of disperse dyes:
1. All oils (auxiliaries) added during spinning or weaving should be removed;
2. The auxiliary used in pre-treatment and dyeing should be washed as much as possible when the process flow is formulated;
3. Test the heat transferability when selecting the post-treatment aid.
Fourth, the detection of fabric thermal migration phenomenon:
Using dimethylformamide (DMF) as the solvent, put the dyed fabric into it for 3 minutes at room temperature, the dye that migrated to the fiber surface will fall into DMF, and the amount of dye shedding can determine the degree of thermal migration of the dispersed dye in the fabric .