摘要：

A can end is formed from a metal sheet having adhered thereto a coating of a semi-crystalline thermoplastic polyester film. The can end comprises a central panel, a panel wall dependent from the periphery of the centre panel, an annular countersink bead extending outwardly from the panel wall, a chuck wall extending upwardly from the periphery of the countersink bead and an annular seaming panel extending radially from the chuck wall. The metal sheet comprises an aluminum alloy having a magnesium content between 0.8% and 2.0% by weight and manganese content between 0.6% and 1.5% by weight; the polyester coating has a crystallinity factor in the range 0.05 to 0.5 measured by X-ray diffraction; and the distance between the chuck wall and panel wall is between 0.85 mm and 1.0 mm as measured at a height of 0.45 mm above the lowest part of the upper surface of the countersink bead.

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