The reason for the uneven thickness of nonwoven fabric
The reasons for the uneven thickness of nonwoven fabric under the same processing conditions may include the following points:
I. Uneven blending of low-melting fiber and conventional fiber: Different fibers have different cohesive power. Generally speaking, low-melting fiber has greater cohesive power than conventional fiber and is less easy to disperse.If the low melting point fiber is unevenly dispersed, the part with less low melting point fiber content cannot form a sufficient network structure and the nonwoven fabric is thinner. In contrast, a thicker phenomenon is formed where the content of low-melting fiber is more.
II. Incomplete melting of low-melting fiber: Incomplete melting of low-melting fiber is mainly due to insufficient temperature. For nonwoven fabric with low basis weight, it is usually not easy to cause insufficient temperature, but for high basis weight and high thickness Special attention should be paid to whether the products are sufficient. The nonwoven fabric at the edge has enough heat, the nonwoven fabric is usually thicker, the nonwoven fabric at the middle part, because the heat is not easy to form a thinner nonwoven fabric.
III. High shrinkage rate of fiber: whether it is conventional fiber or low melting point fiber, if the hot air shrinkage rate of the fiber is too high, it is easy to produce uneven thickness due to shrinkage during the production of nonwoven fabric.