The WICOVALVE® functional principle

• Picture 1

The sealant and the membrane prevent air from entering the packaging.

• Picture 2

The membrane opens as soon as the product generates internal pressure. Depending on the valve type and the packaging content, this may occur at very low overpressure levels. In coffee pouches, for example, the membrane will lift off the seal flange at a pressure level of 3.5 ± 1.5 mbar, allowing the gas to vent.

• Picture 3

The membrane remains open until the overpressure has dropped to below 0.5 mbar. Then, the sealant blocks oxygen ingress (back diffusion) into the packaging, making it airtight again.