Cotton Ply Twist Multipliers in Continuous Reactive Dyeing
Yarn ply twist multiplier controls intra-bundle pore radius; multipliers above 4.0 cause surface ring-dyeing frosting while values under 3.2 provoke migration.
Open Width Soaping
Washing Configuration
Continuous processing of fabric in a flat, spread out state ensures that chemical residues are removed after dyeing or printing. Open width soaping prevents the formation of permanent creases that often occur when fabric is processed in a rope form. The cloth travels through a series of tanks equipped with rollers that maintain constant width and tension.
This method is preferred for high quality woven fabrics and sensitive knits.
Fabric Tension
Control systems regulate the speed of each roller to prevent the cloth from stretching or sagging. During open width soaping, the fabric is subjected to high velocity water sprays and mechanical agitation to dislodge unfixed dye. If the tension is too high, the fabric may become distorted or lose its natural elasticity.
Accurate load cells monitor the force applied to the fabric throughout the entire machine.
Chemical Efficiency
Hot water mixed with detergents and sequestering agents accelerates the removal of hydrolyzed reactive dyes. The design of the tanks in open width soaping promotes counter current flow, where clean water enters at the exit and moves toward the entry. This maximizes the concentration gradient and ensures the most efficient use of water and chemicals.
Crease Prevention
Flat processing is essential for fabrics containing spandex or those with high thread counts. Because the material never bunches together, the risk of dye streaks or uneven washing is significantly reduced. Final results from open width soaping are evaluated by testing the color fastness to washing and rubbing.