Sound insulation fiber aggregate, sound absorbing and insulating material and sound absorbing and insulating material for vehicles

摘要

PROBLEM TO BE SOLVED: To provide a sound insulating fiber aggregate capable of effectively insulating sound with a simple structure, and a sound absorbing and insulating material having the sound insulating fiber integrated body and a sound absorbing and insulating material for a vehicle. A sound insulation fiber aggregate has an average fiber diameter of 450Nm～8500nm, a bulk density of ^{0.09g / cm 3 ~0.33g / cm 3} . Sound insulation fiber aggregate has an average fiber diameter of 450Nm～1650nm, bulk density is particularly preferably from ^{0.09g / cm 3 ~0.22g / cm 3} . By satisfying these numerical ranges, the sound insulation fiber aggregate can be lightweight and effectively exhibit sound insulation performance. [Selection diagram] FIG. 8