Minimizing frictional sound of PU-Nanoweb and PTFE film laminated vapor permeable water repellent fabrics

Abstract

To investigate sound characteristics of PU-Nanoweb (NW) and PTFE film (PTFE) laminated vapor permeable water repellent fabrics, their frictional sounds by walking, jogging, and running speeds were recorded and sound characteristics such as SPL, loudness (Z), sharpness (Z), roughness (Z), and fluctuation strength (Z) were calculated. Mechanical properties were measured by KES-FB system. SPL and fluctuation strength (Z) were significantly increased by increasing speed. Roughness (Z) was generated to be the highest by jogging and running speeds. However, sharpness (Z) was decreased by increasing speeds. NW had significantly lower SPL, loudness (Z), but had higher roughness (Z) than PTFE. NW significantly had less B (bending rigidity), G (shear stiffness), WC (compressional energy), and W (weight). These distinctions influenced the sound characteristics to have the different sound between NW and PTFE. The sound would be low by controlling the mechanical properties and laminated nanoweb and film conditions. The crucial factors were RC and laminated nanoweb and film weight to minimize SPL and loudness (Z) of NW and PTFE at all speeds.