Packaging material and process for producing the same

A process for producing a packaging material having a laminate structure comprising a first polymer layer providing an outer surface which will be directed outwardly upon formation of a packaging container from the packaging material, a second polymer layer providing an inner surface which will be directed inwardly upon formation of the packaging container from the packaging material, and at least a substrate and a grease-proof paper layer formed between the first and second polymer layers, said process comprising:

• (a) providing a substrate and a grease-proof paper sheet,
• (b) subjecting the surfaces of said grease-proof paper sheet to a surface-activating treatment to activate the surfaces,
• (c) melt-extruding a third polymer and a fourth polymer as melts onto respective activated surfaces of said grease-proof paper sheet to form a third polymer layer and a fourth polymer layer, respectively, and to incorporate said third and fourth polymers into said grease-proof paper sheet, said fourth polymer emitting an odor and being melt-extruded at a first temperature,
• (d) laminating said grease-proof paper sheet to said substrate through said third polymer melt, and
• (e) forming and applying said second polymer layer, at a second temperature lower than said first temperature, over said fourth polymer layer to form a barrier to said odor.