The product has a high WVTR rate yet does not allow liquid to pass through. Formulations are available for all humidity increments, with packages designed to control product integrity over a pre-determined shelf life.
Humidi-Pak Inc: Humidity control
Humidity levels in a wide variety of packages can be controlled with the Humidi-Pak (TM) system from Humidi-Pak (Minneapolis, MN). Designed to control and maintain any required humidity level (from 13% RH to 95% RH), it is suitable for storage of food, tobacco, digital film and medical devices.