| 摘要 |
<p>A pressure chamber (2) sealed by the test material (3), is filled with gas, to exceed a given pressure. It is then de-pressurized, by venting through the sample. The time for the pressure to fall from the given upper value to a given lower limit is taken as a measure of the air-permeability of the leather. The gas is compressed air. - An INDEPENDENT CLAIM is included for the apparatus.</p> |
