â–¶What should I do if polyester knitted fabric produces wind prints?

Wind print generally refers to a kind of dyeing defects produced during drying and storage of dyed and processed textiles. The reason why textiles produce wind marks is mainly related to dyes.

In general, a small number of vat dyes, naphtol dyes, and partially vinyl sulfone reactive dyes, and most direct dyes, can produce wind prints because the dye itself has poor fastness to sunlight and oxidation.

Certain reactive dyes have strong sensitivity to alkalis. If the surface is not clean after dyeing, the wind prints (such as active cyan blue KN-G, reactive brilliant orange G, etc.) will be easily generated when the pH is greater than 8. Polyester fabrics are also prone to wind prints during the dyeing and finishing process. However, there are few reports on the root causes and solutions of the wind prints.

When continuous production of polyester fabrics (long-car production line) is not easy to produce wind prints, and intermittent production (during high-temperature and high-pressure overflow dyeing) is easy to produce wind prints. Most of the pleats of polyester fabrics were created after the dehydration of the fabric and before the setting, and the position appeared in the reciprocal folded printing area when the stacker was stored. In severe cases, dozens of lines appear in the zonal direction, and the spacing is exactly the spacing of the reciprocal folds of the grey cloth . Windprints appear as red, white, or dark gray shades in almost the entire width of the web compared to normal dyed areas. What is puzzling is that it cannot be seen before setting. After setting, it will be produced.

Such as non-pulp polyester woven fabrics or polyester knitted fabrics, the process flow is: dyeing → post-processing → dehydration → open width → set shape → fabric inspection after the opening of such fabrics to be shaped after the opening process, reciprocating folding place Exposure to the air, the flow of air causes the moisture in these areas to volatilize and air dry first. Due to the capillary effect, free water from other areas will flock to the reciprocating fold. However, antistatic agents and lubricants added during spinning and weaving, as well as leveling agents and detergents added during dyeing, are still left in the free water carried by fabrics and fabrics. Most of these additives are Non-ionic additives. In the same way as dye migration, when the free water flocks to the reciprocating fold where it is volatilized and air-dried first, the residual agent dissolved in the free water also flocks to the reciprocating fold. With the further volatilization of water, the concentration of auxiliaries at the reciprocating fold is bound to be much larger than other parts.