Gas Transmission
Permeation testing of plastic films defines the primary application for iso 15105-2. This procedure employs an isostatic method to measure gas transmission rates through flexible packaging materials under controlled conditions. High sensitivity sensors detect the concentration of permeant gas passing through a specimen into a carrier gas stream.
The measurement establishes the barrier effectiveness of a material before production conversion.
Permeation Calibration
Differential pressure between both sides of the test specimen drives the gas migration through the film structure. Controlled environmental chambers hold the temperature steady because small fluctuations alter the molecular kinetic energy of the test gas. Flow controllers monitor the steady stream of carrier gas as it collects the permeated molecules for analysis at the detector.
Vacuum systems ensure the downstream pressure remains near zero to prevent back pressure from slowing the flux rate. Analytical software integrates the sensor output over a fixed interval to compute the final transmission value for the material batch.
Barrier Validation
Print quality and shelf life stability depend heavily on these calculated transmission rates for oxygen and carbon dioxide. Extrusion coating lines rely on this validation to confirm that adhesive or barrier layers meet the threshold for protective packaging. Laminate structures often contain multiple layers where the combined gas barrier properties must resist degradation throughout the distribution cycle.
Tight control over the testing variables prevents false negatives in the evaluation of multilayer composite films. Accurate quantification of transmission rates allows converters to optimize gauge thickness without compromising the performance of the final package.
