SOUND ABSORPTION SHEET THROUGH CONTROLING VENTILATION MAP OR AIR POROSITY

摘要

PURPOSE: A glass fiber sound absorbing sheet capable of controlling air permeability and air porosity is provided to improve sound absorbing performance and to enable to be utilized for an acoustic material and system. CONSTITUTION: A sound absorbing sheet comprises a base. An average sound absorbing rate of the sheet at a frequency range of 200-2000Hz is 0.4 or greater. The base comprises 30-60 weight% of a glass fiber and 40-70 weight% of a cellulosic fiber. [Reference numerals] (AA) Sound absorbing rate