SOUND ABSORBING SHEET HAVING MICRO RESONANT STRUCTURE, METHOD FOR MANUFACTURING SAME, AND SOUND ABSORPTION TYPE SOUNDPROOF PANEL USING SAME

摘要

Disclosed are a sound absorbing sheet having a micro resonant structure and capable of improving sound absorption performance up to the low frequency band by means of the micro resonance principle, a method for manufacturing same, and a sound absorption type soundproof panel using same. The sound absorbing sheet according to the present invention has multiple uneven patterns configured to have convex parts and concave parts on one surface of a porous base material, and the area ratio of the concave part determined by the following formula 1 is 40 to 99%. The area corresponding to the concave part has a lower air permeability than the area corresponding to the convex part. [Formula 1] Area ratio of concave portion = [area portion of concave portion]/[area portion of porous base material].