Mechanical Volumetric Dosing Calibration for Textile Pad Dyeing Systems
Mechanical volumetric dosing calibration requires gravimetric cross-verification and pressure-balanced manifolds to prevent shade tailing in pad dyeing.
Reactive Dye Chemistry
Molecular Interaction
Formation of a permanent chemical link between a dye molecule and a textile fiber creates a color that is highly resistant to washing. Reactive dye chemistry involves a reaction where the dye reacts with the hydroxyl groups of cellulose or the amino groups of wool. This process results in the dye becoming an integral part of the fiber polymer.
It only occurs under specific temperature and pH conditions.
Covalent Bonding
Strength of the attachment is much higher than the physical forces that hold other types of dyes in place. In reactive dye chemistry, the covalent bond ensures that the color does not bleed or fade even after multiple domestic laundry cycles. The reaction requires the presence of an alkali to activate the fiber.
Color Fastness
Performance of the dyed garment is evaluated by its ability to retain its shade when exposed to light, perspiration, water and rubbing. Because reactive dye chemistry produces a stable union, these dyes are the preferred choice for high quality cotton apparel. They offer a wide range of bright and saturated colors.
Fixation Yield
Efficiency of the dyeing process is measured by the percentage of the dye that actually reacts with the fiber. Reactive dye chemistry is often accompanied by hydrolysis, where some of the dye reacts with the water instead of the fabric. Improving the fixation rate reduces the amount of color in the wastewater.