SOUND-TRANSMITTING WATERPROOF FILM AND METHOD FOR PRODUCING SAME

摘要

Provided is a sound-transmitting waterproof film that has water proof properties and stable sound-transmitting performance over a wide tonal range. The sound-transmitting waterproof film is formed from a porous film of a synthetic resin, has a water pressure resistance according to JIS L 1092 method B (high water pressure method) of 10 to 400 kPa, and in sound-transmitting performance tests has an acoustic loss at a frequency of 1 kHz of less than 10 dB, an acoustic loss at a frequency of 2 kHz of less than 5 dB, and an acoustic loss at a frequency of 5 kHz of less than 5 dB.