Sound-permeable film, sound-permeable film member provided with the same, microphone and electronic device

摘要

The sound-permeable membrane of the present invention is adapted, when placed over an opening for directing sound to or from a sound transducer, to prevent entry of foreign matters into the sound transducer through the opening while permitting passage of sound, the sound-permeable membrane including a non-porous film or a multilayer membrane including the non-porous film. The non-porous film is formed of oriented polytetrafluoroethylene. This sound-permeable membrane has an unconventional configuration and exhibits various excellent properties. At least one principal surface of the non-porous film may have a region subjected to a surface modification treatment.