Under the same processing conditions, the causes of uneven thickness of non-woven fabrics may be as follows:
1、 Incomplete melting of low melting point fiber: the main reason for incomplete melting of low melting point fiber is insufficient temperature. For non-woven fabric with low base weight, it is not easy to have insufficient temperature. However, for products with high base weight and high thickness, special attention should be paid to whether it is sufficient. The non-woven fabric at the edge is usually thicker because it has enough heat, and the non-woven fabric in the middle part is easy to form a thin non-woven fabric due to the lack of heat.
2、 High shrinkage of fiber: no matter it is conventional fiber or low melting point fiber, if the hot air shrinkage rate of fiber is high, it is easy to produce uneven thickness during the production of non-woven fabric due to shrinkage problem.
3 Low melting point fiber and conventional fiber are not uniform: different fibers have different cohesion. Generally speaking, low melting point fiber has greater cohesion than conventional fiber, and it is not easy to disperse. If the low melting point fiber is not evenly dispersed, the part with less low melting point fiber content can not form enough network structure, and the non-woven fabric is thinner than the low melting point fiber Thick phenomena are formed in places with large quantities.
The problem of static electricity during the production of non-woven fabrics is mainly caused by the low moisture content in the air when the fiber contacts with the card clothing, which can be divided into the following points:
1、 The weather is too dry and the humidity is not enough.
2、 When there is no oil on the fiber, there is no antistatic agent on the fiber. Because the moisture regain of polyester cotton is 0.3%, the lack of antistatic agent results in static electricity during production.
3、 Due to the special molecular structure of silicone polyester cotton, there is almost no moisture on the finish, so it is relatively easy to generate static electricity during production. Generally, the sliding degree of handle is positively proportional to the static electricity, and the smoother the silicon cotton, the greater the static electricity.
4、 In addition to humidifying the workshop, it is also an important work to eliminate the oil-free cotton effectively in the feeding stage.