| 摘要 |
PROBLEM TO BE SOLVED: To provide a waterproof and dustproof thin film having enough waterproofness, dust resistance, sound passing characteristic and air permeability, and excellent support strength and pressure resistance.SOLUTION: A waterproof and dustproof thin film is a thin film shaped asymmetry porous structure having a first surface and a second surface, has a skin layer and an open cell porous layer, contains the skin layer on both sides of the first surface and the second surface, and has a thickness of 1 to 1000 μm, a porosity (a first porosity) of 5 to 91%, a hole diameter of each holes of 0.01 to 15 μm, a Frazier gas flow amount rate of 10 to 60 ft/minft, a Gurley number of 0.3 to 25 sec., water pressure resistance of 5000 to 20000 mmHO and a sound transmission loss of 0.5 to 1.1 dB. |
