Pre-treatment process of cotton knitted fabrics made from different grade cotton fibers with variable physiochemical properties using a single recipe was investigated to obtain a more comprehensive picture about the reproducibility and repeatability of the process. Single jersey knitted fabrics with different characteristic properties, were subjected to same pre-treatment processes. This, Pre-treatment processes included acid demineralization and one bath scouring, peroxide bleaching and optical brightening. The fabrics made of different grade cotton fibers were monitored for metallic impurities, as well the whiteness index, and color coordinates during different steps of finishing and washing. The stability of whiteness after first and fifth washing cycles with detergent for white programmer carried out in industrial washing machine was analyzed by Berger scale and color coordinates and compared with bleached-thermo stabilized knitted fabric.
The results obtained showed that the Pre-treatment process of demineralization followed by one bath scouring, peroxide bleaching and optical brightening is stable giving knitted fabrics with whiteness index with variance coefficient less than three in all three different grade of cotton. Knitted fabrics after first washing cycle have the same whiteness index as before.