Controlling Continuous Dyeing Particulate Migration across Thermal Intermediate Dryers
Intermediate drying needs balanced radiative heat, controlled convection air speed, and pseudoplastic antimigrants to eliminate dye migration across woven fabric.
Reflectance Spectrophotometer
Optical Instrument
Precision hardware that measures the amount of light bouncing off a surface at specific wavelengths provides a numerical description of color. A reflectance spectrophotometer translates the visual appearance of a textile into a set of coordinates known as L-a-b values. The coordinates allow mills to communicate color requirements electronically without shipping physical swatches.
Data Collection
The device shines a light on the fabric sample and records the intensity of the reflection across the visible spectrum. Using a reflectance spectrophotometer eliminates human error caused by eye fatigue or poor lighting conditions. Accuracy improves with averaging.
Software then calculates the delta-E value, which represents the mathematical difference between the production sample and the target color.
System Calibration
Regular maintenance using a white ceramic tile and a black trap ensures the sensor remains accurate over time. The reflectance spectrophotometer must be used on a flat, opaque surface to prevent light from passing through the fabric and skewing the results. Multiple readings are taken and averaged to account for the texture and orientation of the yarns.
Formulation Support
Dyeing laboratories use these measurements to generate initial recipes and adjust production batches in real time. The integration of this hardware into the production flow reduces the time needed for shade matching.