How to prevent color difference in Jigger Dyeing Machine?

1. Equipment inspection and adjustment
Roller pressure uniformity: Check whether the fabric guide rollers and dyeing rollers of the Jigger Dyeing Machine are parallel and whether the pressure is uniform. Use a pressure sensor to detect the pressure difference at both ends of the roller and adjust it to be consistent. The pressure deviation is usually required to be less than 5%.
Cloth roll tension control: Install an automatic tension control system to maintain constant tension. The tension of thin fabrics should be low (such as 0.5-1.5 kg/cm²), and the tension of heavy fabrics can be appropriately increased.
Equipment cleaning and maintenance: Clean the dye tank and rollers regularly to avoid accumulation of residual dyes or auxiliaries. Check whether the circulation pump and filter are blocked to ensure uniform flow of dye.
2. Process optimization
Dye circulation and flow: Increase the dye circulation frequency, shorten the reversing time to 2-3 minutes, optimize the nozzle design or dye spray angle, and ensure that the dye covers the entire width of the cloth.
Temperature and time control: The heating rate should not be too fast. 1-2℃/min is recommended to avoid uneven dyeing caused by sudden dyeing. Extend the heat preservation time to ensure that the dye is fully diffused.
Dye and auxiliaries selection: Choose dyes with good leveling properties, add leveling agents (such as anionic leveling agents 1-2 g/L) or penetrants (such as JFC 0.5-1 g/L).
3. Operation specifications
Grey cloth pretreatment: Ensure that the grey cloth is thoroughly desized, refined, and bleached, and the pH value of the cloth surface is neutral (6.5-7.5), and avoid local impurities that hinder dye adsorption.
Cloth rolling method: Use "edge rolling" to avoid uneven tightness at both ends of the cloth roll. A photoelectric correction device can be installed, and manual auxiliary finishing is performed during the initial cloth rolling to ensure that the cloth surface is flat and wrinkle-free.
Dyeing process monitoring: Regularly check whether the surface of the cloth roll is flat, and stop the machine for adjustment in time if abnormalities are found. Record the state of the dye solution (such as chromaticity and foam volume) at each reversal.
4. Raw material management
Grey cloth consistency: Grey cloth of the same color number should be from the same supplier and batch as much as possible to avoid color difference due to grey cloth differences.
Dye management: Dyes should be stored separately according to origin and batch number, and the color of each batch of dyes should be strictly tested to ensure consistency.
Pretreatment quality: Pretreatment should ensure uniformity and consistency to avoid color difference during dyeing due to uneven pretreatment.
5. Special problem handling
Left-center-right color difference: Check whether the dye nozzle is blocked, adjust the position of the cloth in the dye tank, and avoid low local dye flow rate.
Front and back color difference: Increase the permeability of the dye (such as increasing the bath ratio to more than 1:3), or use a double-sided circulation dyeing process.
Intermittent color difference: Check whether the dye temperature fluctuates too much (±0.5℃ accuracy is required), or whether the dye is not fully dissolved.