Air permeance of paper or board

Air permeance is an important property for some paper grades, such as paper bags that are filled industrially. Measulabs offers air permeance testing with the Bendtsen or Gurley methods: Bendtsen method (ISO 5636-3) - For papers with permeance of 0.35 µm/(Pa*s) to 15 µm/(Pa*s). Not for rough-surfaced papers that cannot be securely clamped to the device. This result is expressed as ml/min, which expresses the average volume of air that passes through the material in a minute at elevated pressure. Gurley Method (ISO 5636-5) - For papers with permeance between 0.1 µm/(Pa*s) to 100 µm/(Pa*s). This test may also be used to determine the air resistance of paper and board. In this test, the time it takes for a certain volume of air to pass through the paper at a certain pressure is measured in seconds.