Alkaline Treatment
Chemical modification of cotton yarns or fabrics under high tension using concentrated alkaline solutions permanently alters the physical and optical properties of the cellulosic fibres. This process of sodium hydroxide mercerization swells the cell wall and increases the surface lustre of the material. Textile finishers use this treatment to improve dye affinity and dimensional stability.
Structural Phase
Transition from cellulose I to cellulose II occurs during this exposure. The swelling of the fibers disrupts the natural crystalline structure, converting the flat cotton ribbon into a round cylinder. This phase change is permanent.
Physical Property
Dye uptake increases by up to forty percent because the treatment opens up the crystalline regions of the cellulose. This increased accessibility allows more dye molecules to penetrate the fiber core, resulting in richer, deeper colors with less dye consumption. The treated fabric also exhibits increased tensile strength and better resistance to shrinkage during home laundering.
These physical enhancements make the fabric highly desirable for premium apparel and home textiles where durability and color brilliance are essential.
Treatment Limit
Temperature and concentration controls are critical to prevent degradation of the cellulosic polymer chains. The concentration must be maintained between twenty and thirty percent at a temperature below twenty degrees Celsius for optimal results. If the alkaline solution is too concentrated or too hot, it can damage the fibers, causing them to lose strength and elasticity.
