An intermediate laminate product, an expanded laminate structure, and process manufacturing thereof

Abstract

An intermediate laminate product includes a first paper layer including lignocellulose fibres, and a dry coating layer applied to one surface of the first paper layer, the coating including expandable microspheres having an expansion temperature (TE), at least one polysaccharide, and a plasticizing additive which is capable of forming a thermoplastic blend with the polysaccharide. An expanded laminate structure includes the intermediate laminate product and a second paper layer comprising lignocellulose fibres, which is attached to the dry coating by heat lamination. A liquid packaging board includes the expanded laminate structure and a liquid barrier layer. A process for forming the expanded laminate structure includes applying a second paper layer to the coating of the intermediate product at a second temperature (T2), which is above the expansion temperature (TE) of the microspheres, whereby the microspheres expand, and at which the plasticizing additive causes plasticizing of the polysaccharide, to form a thermoplastic blend.

Dependencies are inferred from the claim text.