Thesis Details

Thesis Title: Effects of dye dispersion stability on dyed fabric quality
Thesis Author: Jamison Edwards
Abstract: Nonionic surfactants are specifically used in fabric preparation to remove mineral oils added to manufactured fibers, such as polyester, during spinning and texturing. However, nonionic surfactants left on the fabric after preparation may have negative effects on the polyester-disperse dyeing system. The mechanisms of dyeing polyester with disperse dyes is well known, but far less is known about how dyebath additives influence the dyeing process. Previous research has shown that nonionic surfactants used in disperse dyebaths may negatively affect the dyeing process and dyed fabric quality. This research studied the effects of nonionic surfactant type, nonionic surfactant concentration, and disperse dye type on dye dispersion stability and dyed fabric quality. This work determined that nonionic surfactants left on the fabric after preparation do have an effect on dyeing. When nonionic surfactants are present in the dyebath, dye staining, dispersion stability, shade, and colorfastness may be affected. Observations gathered from dye dispersion stability testing suggested that forces in the dyebath and the dyebath temperature play important roles in dye staining. Furthermore, some nonionic surfactant/disperse dye combinations significantly reduced the depth of shade of the dyed fabrics. This phenomenon resulted from a reduction in dye uptake. The presence of some types of nonionic surfactants in the dyebath significantly affected the equilibrium dye sorption by decreasing the chemical potential of the dye in the dye bath, which significantly reduced the dye uptake. Therefore, less dye diffused into the fiber, which had noteworthy repercussions on the resultant shade of the dyed fabric.