Yarn Dyeing Faults: Their Causes And Remedies

Yarn Dyeing

Dyeing is the combination of reactions among fiber, dyes, chemicals, and water. In the dyeing process, different faults can occur for various factors. Among all of the dyeing processes, package yarn dyeing is different. In package yarn dyeing different types of faults are occurs but the following are the most common.

Yarn Dyeing Faults: Their Causes And Remedies

Uneven Dyeing

A textile engineer must have knowledge about the shade of color. A small percentage of shade difference can move material to rejection. So, it needs to be highly careful during dyeing. Dyeing is a continuous process and during dyeing, one should be sure about the shade of materials that matched the standard swatch. Uneven shade means the variation of shade in a different layers of a yarn package. We know that package yarn dyeing is done by the In-0ut mechanism of dye liquor. So shade could be varying in the various layers of a package. Followings are the causes and remedies of uneven shade.

Causes

• Firstly, uneven pretreatment (uneven scouring & bleaching).
• Secondly, improper color dosing.
• Thirdly, using dyes of high fixation property.
• After that, uneven heat-setting in case of synthetic fibers.
• Lastly, lack of control on dyeing machine.

Remedies

• Firstly, by ensuring even pretreatment.
• Secondly, by ensuring even heat-setting in case of synthetic fibers.
• After that, proper dosing of dyes and chemicals.
• Lastly, proper controlling of dyeing m/c.

Batch to Batch Shade Variation

In dyeing; dyeing is done according to the buyer’s requirement. An order for a specific shade could be a small amount or a large amount. In the mill, the different batch is made as per order or depending on the capacity of the machine. For this reason batch to batch, shade variation could take place. The following are the causes and remedies way of the batch to batch variation.

Causes

1. Fluctuation of Temperature.
2. Improper dosing time of dyes & chemicals.
3. Batch to batch weight variation of dyes and chemicals.
4. Dyes lot variation.
5. Improper reel speed, pump speed, liquor ratio.
6. Improper pretreatment.

Remedies

1. Use standard dyes and chemicals.
2. Maintain the same liquor ratio.
3. Follow the standard pretreatment procedure.
4. Maintain the same dyeing cycle.
5. Identical dyeing procedure should be followed for the same depth of the Shade.
6. Make sure that the operators add the right bulk chemicals at the same time and temperature in the process.
7. The pH, hardness and sodium carbonate content of supply water should check daily.

So, friends make sure about the yarn dyeing faults and take steps to remove them.