DC pseudo plasma discharge treatment of polyester textile surface for disperse dyeing

Polyester fibers are hydrophobic in nature; most of the successful preparations such as dyeing, printing, and finishing are based on wet treatments. The plasma treatments for polyester textile surfaces using low-pressure pseudo-discharge in nitrogen as a working gas are discussed in this work. Different plasma parameters, e.g., pressures of 0.06, 0.1, and 0.2 torr; different times (15-600 s); and different currents (1-6 mA), are applied on textile samples in nitrogen plasma. The wetability of the treated specimens was increased by increasing either the electric current or the time at the treatment pressure. The plasma treatment of the polyester fabrics improved for their hygroscopicity and in turn their performances during the dyeing with disperse dye. The optimum exposuring conditions for high water absorbance and best color (expressed as the lightness (L), red-green (a), and yellow-blue (b) coordinates with the CIE Lab color measuring system) were exposure time (15 s), pressure (0.1 tort), and electric current (5 mA). Meanwhile the exposed samples showed no significant deterioration for their mechanical properties expressed as tensile strength and elongation percent, and the results were proved by the examination of the treated samples using a scanning electron microscope.