■ What is an aluminium blister?
High-quality tablets are packed in blisters to protect them from environmental influences, atmospheric oxygen and moisture, because this is the only way the ingredients retain their effect. This protection is made possible by the aluminium cover foil on the underside of the blister.
■ What types of aluminium foil are there?
Both soft and hard aluminium foils are used for the lid foils of the push-through packs.
Blister foil made of hard aluminium
In most cases, a hard aluminium foil is used. This has only a low stretching force. The advantage of this is that it breaks relatively quickly and releases the medicine when relatively little force is applied.
Blister foil made of soft aluminium
If a soft aluminium foil is used, more force must be applied to reach the medicine, as the foil has a higher stretching force. Thus, blister packaging with lidding foil made of soft aluminium is considered more child-resistant.