| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide sound insulation material composed of resin foam, which is lightweight and has excellent sound insulation effect without secondary processing such as covering of an internal surface or an external surface with a resin film.SOLUTION: Sound insulation material is composed of polyurethane resin foam, a permeability of the polyurethane resin foam measured in accordance with JIS-L1096 is 0.05 to 20 cm/cm/sec, and an average value of a ratio of the long diameter/short diameter of a cell constituting the polyurethane resin foam is 1.5 or more. It is preferable that the resin foam is arranged so that sound enters in a long diameter direction of the cell, permeability is secured while sound collides with a cell membrane, thereby obtaining excellent sound insulation performance.</p> |
