Structure of the opening curl of a bottle-type can

Abstract

To provide a structure of an opening curl part of a bottle type can, that is less likely to damage a tamper-evidence property via excellent form maintainability with respect to a load from above.SOLUTION: A curl part 10 comprises an inner peripheral wall part 16, an upper end R part 17, an outer peripheral wall part 20, a lower end R part 21, a folding piece part 22, and a tip edge part 23. An inclined wall part 15 where an outer diameter is gradually increased by downwardly connecting to a screw from the inner peripheral wall part 16. A retreat surface 24 for which a curvature radius R2 on a cross-section when being cut on a flat face passing through a center axis line O of a neck part, whose curvature center P2 is present outside the neck part is larger than another curvature radius R1 of the lower end R part 21 is provided, while extending downward from a lowermost end part 25 at which the folding piece part 22 comes into contact with a connecting part from the inner peripheral wall part 16 to the inclined wall part 15.SELECTED DRAWING: Figure 3

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