| 摘要 |
PURPOSE:To provide a mask excellent in low pressure loss, high catching efficiency and portability by enveloping a perforated film formed of an organic polymer to specify the intake resistance and average bore of the perforated film. CONSTITUTION:A mask envelops a perforated film formed of an organic polymer. The pressure loss of the perforated film is preferably 8mmH2O or less when 30l/min of air flow is passed through. When the pressure loss exceeds 8mmH2O, the intake resistance is so high that breathing gets difficult. This perforated film has fine apertures on the one surface which have 0.2-10mum of average bore opened substantially perpendicular to the film surface and 35-95% of opening rate so that the vacant aperture rate ranges 50-95%. |
