Desorption Kinetics of Hydrolyzed Reactive Dyes in Continuous Wash Ranges
Continuous wash ranges clear hydrolyzed reactive dye by maximizing thermal diffusion and maintaining steep counter-current concentration gradients across wash stages.
Intermediate Wet Pick Up
Moisture Retention
Padding operations in continuous dyeing ranges rely on controlled liquid application to ensure uniform chemical distribution before the drying stage. Maintaining a stable intermediate wet pick up prevents the migration of dissolved chemicals toward the fabric surface during subsequent infrared pre-drying. This parameter is monitored at the exit of the padder.
Wetting Uniformity
High variation in fabric density, fiber blend composition or loom state preparation alters the amount of liquor held between the yarns. When fabric enters the padder, a high liquid retention level can dilute the incoming chemistry or cause uneven chemical fixation. For this reason, moisture sensors are placed across the fabric width to measure the water content.
Chemical Application
The dyer controls this parameter by adjusting the nip pressure of the squeeze rolls and the fabric speed through the trough. Lower squeeze pressure yields a higher pickup, which provides more chemical for reaction but demands more thermal energy to evaporate during dry-off.
Production Variance
In consistent run settings, a variation of more than five percent in the pickup value signals a mechanical issue or a shift in fabric absorbency. This variation leads to color shade differences between the left, center and right sections of the textile roll.