Fiber aggregate for sound insulation, sound absorbing/insulating material, and sound absorbing/insulating material for vehicle

摘要

[Problem] To provide a fiber aggregate for sound insulation that is able to effectively insulate sound by a simple structure, a sound absorbing/insulating material and a sound absorbing/insulating material for a vehicle that comprise this fiber aggregate for sound insulation. [Solution] This fiber aggregate for sound insulation has a mean fiber diameter of 450-8500 nm and a bulk density of 0.09-0.33 g/cm