SOUNDPROOF MATERIAL, SOUNDPROOF STRUCTURE, AND CONSTRUCTION METHOD OF THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a soundproof material which can absorb or insulate an airborne sound effectively in spite of being a lightweight and a simple structure.SOLUTION: A soundproof material 6 which may contact an inner wall of a hollow double wall structure having an air layer inside and is for insulating an airborne sound includes: a buffer layer 6a formed of a shock absorbing material with an apparent density of 0.03 to 0.7 g/cm; and a mass layer 6b having a larger density than that of the buffer layer 6a. The mass layer 6b is formed of a first mass layer 6b1 and a second mass layer 6b2 having a smaller density than that of the first mass layer.