Optimize the protection of your packaging with water vapor transmission rate analysis
The Water Vapor Transmission Rate (WVTR) is a key parameter for assessing the permeability of a material to water molecules in gaseous form. This analysis is essential for the food, pharmaceutical and cosmetic industries to ensure optimal preservation of packaged products by limiting their exposure to humidity.
The assessment of the water vapor transmission rate allows the selection of packaging materials adapted to the requirements of protection against humidity, thus guaranteeing the stability of sensitive products.
How Water Vapor Transmission Rate Analysis Works
The assessment of the water vapor transmission rate is based on standardized methods allowing reproducible and reliable measurements to be obtained.
- Gravimetric method – A sample of material is placed between a chamber containing water and another exposed to a dry environment. Moisture absorption is measured by the change in mass of the sample over a given period.
- Manometric method – The sample is subjected to a vapor pressure difference between two compartments, and the transmission rate is determined by the pressure variation in the dry compartment.
- Humidity sensor method – The sample is placed in a test cell where the humidity change is monitored in real time by a high-precision sensor.
These techniques guarantee measurements adapted to industrial requirements, making it possible to optimize the barrier performance of materials.
Technical characteristics of water vapor transmission rate analysis
Water vapor transmission rate analysis is performed according to rigorous protocols ensuring accurate results. Key features include:
- Units of measurement : g/m²/24h (grams of water vapor transmitted per square meter in 24 hours).
- Reference standards : ASTM F1249, ISO 15106, DIN 53122.
- Measuring ranges : from 0.01 to 1000 g/m²/24h depending on the equipment used.
- Controlled temperature and humidity : simulations at 23°C, 38°C or other specific conditions to reproduce the real packaging environment.
- Samples tested : plastic films, papers, cardboards, composites and barrier coatings.
These parameters ensure precise and reproducible analysis of the barrier performance of the materials tested.
For which matrices?
Water vapor transmission rate is a key indicator for many materials used in the packaging industry. The matrices analyzed include:
Main industrial applications
Léa Géréec
Technical and scientific advisor
