Fractal Characteristics of Contact Surface of Needle Punched Nonwovens

In this work, we analyzed the fractal characteristics of the contact surface of needle punched nonwovens with different contents of polyurethane compressed under different pressures. Fractal dimensions, Da and Dg, were used to evaluate the fiber area distribution and grayscale distribution of the contact surfaces respectively. The results show that both Da and Dg increase with the increasing compressing stress. The more polyurethane the nonwoven contains, the larger Dg and smaller Da it has.