Spunlace non woven has good air permeability and can be used in many industries, such as sanitary napkins, diapers, masks and other surface materials. Its permeability has a great influence on the filtration effect. This paper analyzes the main factors affecting the permeability of spunlace non woven fabric.

1.Effect of mass per unit area on the permeability of spunlace non woven

One of the key factors affecting the permeability of products is the mass per unit area of nonwovens. By testing the air permeability of spunlace non woven under different unit area mass, it is concluded that with the improvement of unit area mass, the air permeability of spunlace cloth gradually decreases, and when the unit area mass increases to a certain extent, the downward trend tends to be gentle. When the mass per unit area of the product is less than 45g/ square meter, the air permeability decreases faster. This is because when the mass per unit area of Spunlaced cloth exceeds 45g/ square meter, the fibers can be arranged in a very dense way. When the mass per unit area is smaller than 45g/ square meter, the uniformity of the cloth surface of spunlaced products will gradually become worse. If the carding and spunlaced process control are unreasonable, there will sometimes be obvious small holes in the cloth surface, resulting in the increase of air permeability. To sum up, the higher the quality per unit area, the thicker the product, the greater the area density, the tighter the fiber arrangement under the entanglement of water spikes, the less the pores, and the stronger the blocking effect on air.

2.Effect of mesh laying method on the permeability of spunlace non woven

Spunlace non woven has two ways of laying nets: direct laying and cross laying. Under the carding of the fiber re carding machine for direct laying products, the fibers are arranged longitudinally, and only a small amount of fibers change direction under the action of the messy roller or the condensation roller. The effect of straight laid products is that the longitudinal parallelism of fibers is high and the gap is relatively large. When laying products, the fiber net is laid many times according to a certain angle, and the fibers are crisscrossed. The spatial structure of the fiber net is more messy. The crisscross of vertical and horizontal fibers makes the gap between the fibers smaller and denser. Generally, the vertical and horizontal strength ratio of straight laid Spunlaced cloth is 3.5~5.5, and that of cross laid Spunlaced cloth is 1.0~1.8, and the vertical and horizontal strength is basically close. Two groups of cross laid and direct laid products with different unit area mass and the same polyester viscose ratio were selected for air permeability experiments, from which it was concluded that the air permeability of direct laid products was better.

3.The influence of cloth surface type on the permeability of spunlace non woven

Plain weave, jacquard and mesh are three kinds of more common spunlace non woven cloth surface. According to the hole density, mesh products with 22 mesh and 40 mesh are more common.

Through experiments, it is found that there is no obvious difference in the air permeability between the straight laid plain weave and the jacquard Spunlaced cloth, which indicates that the overall uniformity of the jacquard Spunlaced cloth is not much different from that of the plain weave, the fiber distribution is relatively uniform, and the air permeability of the mesh Spunlaced cloth is significantly increased, because the small holes on its surface increase the gas permeability, and the air permeability of products with different pore diameters and densities is also different. The pore diameter of 22 mesh products is larger than that of 40 mesh products, It has stronger air permeability and higher air permeability.

With the rapid development of nonwovens, the application field of spunlace non woven is also gradually expanding. It is of great significance to discuss and analyze the permeability of spunlace non woven fabric for its production guidance.