Читать книгу Packaging Technology and Engineering - Dipak Kumar Sarker - Страница 28

Composite packaging is made from combining at least two different and often physically distinct materials. The goal in combining various materials is to increase the mechanical and chemical properties of the materials over those observed in any single material. Sometimes composite materials also demonstrate unique properties not seen with either individual material through an effective synergism in the physical properties of each material. Commonly used examples include plastic–aluminium composite packaging used for steam retortable pouches; cardboard–PE composite packaging used for Tetra Brik® cartons; paper–PE composite packaging, frequently used for medical sachet pouches; plastic–paper–aluminium composite packaging used for UHT sterilised product cartons; and paper–aluminium composite packaging used as the webbing for pharmaceutical push‐out packs. In some more modern combinations hemp and flax woven materials are embedded within plastic to produce more rigid materials and a range of contemporary ‘bioplastics’ make use of this composite structure.