Coextruded foil composite material and its use in card bodies

A data card body of a portable data carrier comprising:

• a card core including at least one core layer,
• a first cover layer covering a first surface of the card core, and
• a second cover layer covering a second surface of the card core,
• wherein at least one of the first cover layer or the second cover layer or at least one intermediate layer comprises a foil composite material, the foil composite material including
• an inner layer formed between a first outer layer and a second outer layer, wherein the first outer layer, the inner layer, and the second outer layer jointly form a coextruded composite,
• within the coextruded composite, the first outer layer is in direct contact with a first surface of the inner layer, and the second outer layer is in direct contact with a second surface of the inner layer, the second surface of the inner layer being opposite from the first surface of the inner layer,
• the first outer layer includes at least a first partial layer and a second partial layer, the second partial layer being between the first partial layer and the inner layer, the first layer containing 95 wt. % or more polyethylene terephthalate glycol copolymer (PETG),
• the inner layer consists essentially of 100% of a single thermoplastic copolyester elastomer (TPC) material or consists essentially of a plurality of inner plastic layers, each of the plurality of inner plastic layers consisting essentially of a same thermoplastic copolyester elastomer (TPC), and
• the second outer layer comprises polyethylene terephthalate glycol copolymer (PETG),
• wherein the first outer layer, the inner layer, and the second outer layer jointly form a coextruded composite formed by the materials of each of the first outer layer, the inner layer, and the second outer layer are coextruded by being merged into said coextruded composite before leaving an extruder nozzle,
• wherein the inner layer constitutes 60 to 80% of a total thickness of the foil composite material
• wherein a thickness of each of the first outer layer and the second outer layer is in the range of 10 μm to 70 μm, and
• wherein the first partial layer and the second partial layer of the first outer layer include a mixture of PETG and TPC and the content of TCP is higher in the second partial layer than in the first partial layer and the content of PETG is higher in the first partial layer than in the second partial layer.