Chemical migration from multi-layer packaging into food

Chemical migration from multi-layer packaging into food 

Typical substrates found in flexible multilayer packaging and reasons for their inclusion are summarised in Table 16.1. Individual component layers in flexible materials normally range in thickness from 2.5 pm to -125 pm, with the total thickness normally being less than 250 pm. Thicker laminates are normally considered to be sheet materials and are rigid in nature. 

Polyamides and ethylene vinyl alcohol do not readily adhere to polyolefins, so a laminating adhesive or tie-layer is necessary to hold the coextruded stmcture together. Other polymers such as polycarbonate (PC) or polyethylene terephthalate (PET) are also used as outer layers in multi-layer stmctures. 

Paperboard Aluminium foil Metallised frkn Ethylene acrylic acid (EAA) 

Provides stiffness and barrier to light transmission. Provides a barrier to oxygen, moisture and light. Provides a barrier to oxygen and light. 

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