It is very easy to wrinkle (chicken paw mark) when dyeing polyester superfine fiber ground fabric, especially when the color of scarlet, navy blue and dark gray occurs, it is difficult to repair. Most of the fabrics are 75d72f (Warp) × 150D / 228f (weft), 144 × 93 in density and 4000 PX in width. In general, desizing → pre setting → sanding → dyeing → stretching and setting → finished product inspection and dyeing and finishing are adopted.

Practice has proved that there are many factors to form wrinkle. For example, the warp and weft tearing strength of the fabric decreases by 11% and 50% respectively after desizing and sanding. After high temperature dyeing at 130 ℃, the molecular chain movement in the crystallization zone of the fabric is intensified due to the absence of glume. In addition, the pressure of the nozzle on the dyeing machine and the high-speed friction of the cloth guide roller cause the fabric to fold in the machine and be fixed with different angles. In particular, the slower the fabric rotation speed is, the dyes in the dyeing bath will gather in the fabric deformation area. The higher the concentration is, the deeper the crease print will be (obvious). It is not helpful to take measures such as slow cooling.

After repeated practice, it is found that in order to overcome this kind of crease printing, the following improvements must be made:

(1) The fabric should be desized by compact desizing equipment, such as open width scouring machine and roll dyeing machine, so as to ensure the smooth rolling of the fabric.

(2) The preset shape must be regarded as the final shape, that is, 190-200 ℃× 30s, and the actual temperature of the main setting box in the heat setting machine must be strictly controlled. The moisture content of the setting fabric must be 5% - 7%, and it should not be too dry, especially when the climate is relatively dry in autumn and summer.

(3) Sanding paper should not only be smooth and even, but also control the technical parameters such as tension and speed. It is found in practice that in order to select sandpaper and adjust the horizontal roller, the technical parameters should be determined according to different specifications of products and standard samples. It is difficult to ensure dimensional stability and fabric strength reduction is very serious if the fabric is overheated due to the poor levelness of the roller.

Influence of different processes on fabric strength reduction

Process warp and weft

Grey cloth 3.76 3.2

Before setting 2.16 2.08

After sanding 1.92 1.04

(4) In order to select disperse dyes with good quality, disperse dyes with high color fastness should be selected, and high temperature leveling agent with good migration property should be added. It has been proved that the dyeability of the mending agent is good, such as adding the mending agent wt-l9 (Guangzhou Huanian) as the retarding agent, at the same time adding 1% - 1.5% of the high temperature bath wrinkle inhibitor, such as the bath wrinkle inhibitor wt-bh (Guangzhou Huanian), to ensure uniform dyeing. In addition, special attention should be paid to the cooling rate in the dyeing process. Generally, 1 ℃ / min is appropriate. Finally, in the dyeing operation, the pressure of the mechanical nozzle and the cloth guide roller must be reduced to the minimum to minimize the friction between the equipment and the fabric.

It is better to dry the fabric on the short ring crawler dryer before heat setting. This is also one of the ways to reduce wrinkle formation.