Methods to improve dye fastness

Although some dyes can produce brighter colors, due to the water-soluble groups on the dyes, the wet fastness is poor, and the fading and staining phenomena are serious, which not only makes the textile itself look old, but also the dyes will stain the white or other colored fibers when they fall off, resulting in staining and color matching.

In addition, although reactive dyes can form covalent bonds with cellulose fibers, if there are hydrolyzed dyes or the unbonded dyes are not soaped sufficiently during dyeing, the wet fastness will also decrease; in addition, reactive dyes that have formed covalent bonds with fibers e fastnmay also decompose and break bonds under acidic or alkaline conditions, as well as problems such as insufficient chloriness, perspiration fastness, and sunlight fastness.

In order to improve the color fastness of fabrics, color fixation can be carried out. These auxiliaries that can improve the fastness of various dyeing are called color fixers.

Color fixation principle of color fixers

1. Generate insoluble color lakes on the fabric, block soluble groups, and make the dyes on the fabric difficult to dissolve and fall off when exposed to water, so as to achieve the purpose of improving wet fastness. However, after these fixing agents fix the color, the color of the fabric may change or cause the light fastness to decrease.

2. Generate a mesh film on the fabric to prevent the dye from falling off.

3. Use the reactive groups in the fixing agent molecules to cross-link with the reactive groups on the dye molecules and the hydroxyl groups on the cellulose molecules to improve the fixing effect of the dye on the fiber.

4. Use the molecular attraction between the fixing agent and the fiber to increase the fixing strength of the fixing agent, thereby improving the color fastness.

If you want to know more about dyeing solutions, please contact:  info@sylicglobal.com