| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a waterproofness dust resistant thin film assembly having efficient waterproofness, dust resistance, sound passing property and air permeability, as well as having excellent support strength and pressure resistance.SOLUTION: A thin film-like asymmetry porous structure having a first surface and a second surface, comprises an open cell porous layer and a skin layer which is either on the first surface or the second surface and occupies 0.04 to 40% of the thickness of the asymmetry porous structure, and has the thickness of 1 to 1000μm, a void ratio (first void ratio) of 5% to 91%, a bore diameter of each pore of 0.01μm to 15μm, a Frazier gas flow amount of 10 to 60 ft/minft, a Gurley number of 0.3 to 25 sec., a water pressure resistance of 3000 to 20000 mmHO, and sound transmission loss of 0.5 to 2.5 dB.</p> |
