Cationization of cotton fabrics was performed utilizing 3-chloro-2-hydroxypropyltrimethylammonium chloride (CHPTAC) in a cold pad batch procedure. Cotton fabrics were cationized at three levels 2.11, 4.23, and 8.45 % on weight of fabric of CHPTAC. Different neutralization schemes were employed on each cationization level to determine the effect of pH and process parameters on minimizing the amount of free trimethyl amine (TMA) in cationized cotton. Employing a solvent extraction method and gas chromatography/flame ionization detection (GC/FID), TMA was extracted and determined in parts per million (ppm) from the neutralized and sealed and aged cationized fabric. The results show that it is straightforward to quantify the concentration of TMA in cationized fabric and that the lowest levels of TMA in cationized cotton are achieved with by an initial warm rinse to remove excess sodium hydroxide, followed by acidification bath to achieve an acidic pH, and ending with a subsequent cold final rinse.

Cationisation allows cotton to be dyed with anionic dyestuffs (including anionic pigment dispersions) without the need for salt, and with decreased usage of dye, water, and energy. Appropriate cationisation levels play a part in dyeing properties such as fabric levelness, in fastness properties such as lightfastness, and in the overall cost of the cationisation treatment. The objective of this work is to assess whether it is possible simultaneously to predict a dye recipe and cationisation treatment level for cotton to yield a colourless or nearly colourless dyebath at the completion of the dyeing to match the shade of conventional fibre reactive dyeing of cotton. It has been shown that it is possible to model a cold pad batch cationisation process, relate the colour yield data and cationisation level for individual dyes, and finally predict a dyeing recipe and the required corresponding cationisation treatment to match the shade of conventional fibre reactive dyeing of cotton. The predicted dye recipe and cationisation amount yield colourless or nearly colourless dyebaths at the conclusion of the dyeing process.

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UV protection is a key quality attribute for many consumer products such as sunscreens, paints, coatings, and textiles. One common UV protection mechanism, especially for sunscreens, uses metal oxides. Researchers have explored the use of metal oxides, in particular, TiO2 and ZnO, for their UV protection, antimicrobial efficacy, and self-cleaning properties on cotton specimens. This work examines whether three TiO2 extender pigments commonly used in the paints and coatings industry, calcium carbonate, kaolin clay, and barium sulfate, can impart UV-Vis opacity to a reactive dyed cotton/spandex knit fabric. Barium sulfate coatings were found to greatly improve dyed cotton/spandex fabric opacity in both the UV and visible light of the electromagnetic spectrum. Barium sulfate coatings yielded exceptional UV protection on dyed cotton/spandex fabric.