Plastic coatings are used on paperboard to give a protection against wet or aggressive products and to provide a barrier against moisture loss and gas transfer. The construction of the package and its closures is in many cases the factors which limit for the total protective function of the package.
The shelf life of the packed product depends on parameters such as:
- Quality and geometry of the product
- Filling level in the package
- Exposed area of the product
- Chemical properties of the product
- Storage conditions
Read more: “We chose Incada from Iggesund because of its stiffness and we coated the inside with a barrier of black-dyed polyethylene"
Tony Norén, Elanders
When selecting a suitable protective plastic barrier it is necessary to refer to previous experience with similar packing requirements and also to consider the specific barrier. Typical values for our most common plastic coatings are tested according to ASTM F-1249/ DIN 53122 (water vapour permeability) and ASTM D-3985/DIN 53380 (oxygen permeability).
To attain specific properties, paperboard is combined with various plastics, films, foils or other additional paperboard layers. Complete descriptions of the product can be acquired by studying the specifications of the coating together with the specifications of the paperboard product.
The choice of material is determined by the desired properties. These can be barriers against moisture and grease, heat tolerance, strength or combinations of these qualities. By using paperboard as a carrier for the plastic, the amount of plastic used can be reduced to about a fifth of what would have been required for an equivalent plastic container.