How to prevent the chicken paw print on the fabric during dyeing with overflow dyeing machine?

1. Potential factors in spinning and weaving

For example, uneven yarn evenness and twist shrinkage after twisting, tension and density differences during weaving, especially high-count and high-density fabrics, will all affect dyeing.

2. The thermal shrinkage of two or more fibers in the blended fabric is inconsistent

Sometimes even though the fabric is pre-shaped, there is still residual stress, especially the difference in thermal shrinkage at 130°C is more significant.

3. The dyeing bath ratio is too small

The length of each tube of fabric should be controlled within 350-400 ITI as much as possible, and its operating cycle roughly coincides with the theoretical number (ie 1r/min). The design capacity of the machine and the circulation function are sometimes inconsistent, and most dyeing machines are generally in o. Around 5r/rain, if the bath ratio is too small at lr/(3～4)rain, it is not only easy to dye flowers, but also easy to form prints, especially light and high-density fabrics, such as polyester plain spinning and pongee spinning. .

4. The temperature rise/fall speed is too fast

Dyeing on the overflow machine, heating and cooling will directly affect the shrinkage of the fiber, thereby forming a print. For thermoplastic fibers such as nylon, once a fold print is formed, it will be irreversible. Therefore, during dyeing, special attention should be paid to slowly increasing/decreasing the temperature within 10°C before and after the glass transition temperature of the fiber. Generally, the speed of 1°C/rain is appropriate.

5. The fabric after heat treatment cannot be cooled instantaneously

Do not rush to drain the liquid after dyeing. You should gradually add cold water in the middle of the operation, wash with running water, and wait for the temperature to drop before draining. You can also change the liquid for cleaning.

6. Reasonable choice of processing equipment

There are suitable equipment for the dyeing and finishing of various fabrics, which should be selected according to the performance and end use of the fabric.