Patent ID: 6913158

Claim:
A closure cap ( 1 ) for a container containing a carbonated beverage comprising an end panel ( 2 ) joined at a radius portion ( 7 ) to a depending peripheral skirt ( 4 ); said end panel ( 2 ), radius portion ( 7 ) and depending peripheral skirt ( 4 ) each including an inner surface; said radius portion inner surface defining a transition surface between said end panel inner surface and an uppermost peripheral inner surface portion of said peripheral skirt inner surface; a cap thread ( 6 ) below said uppermost peripheral inner surface portion of said peripheral skirt inner surface for threading the closure cap ( 1 ) to an associated container mouth, a plurality of peripherally spaced substantially stiff reinforcing rib means ( 8 , 38 , 48 , 58 ) for stiffening said peripheral skirt ( 4 ) at said uppermost peripheral inner surface portion and said end panel ( 2 ) at said transition surface thereby preventing at least one of radial outward peripheral skirt bulging and spreading between the peripheral skirt and the end panel; said plurality of reinforcing rib means ( 8 , 38 , 48 , 58 ) being a plurality of reinforcing ribs extending axially from said end panel inner surface along and projecting radially inwardly from and beyond said uppermost peripheral skirt inner surface and terminating contiguous said cap thread, said cap thread ( 6 ) having a thread end portion located contiguous said uppermost peripheral inner surface portion, a plane through said thread end portion defining an imaginary screwing line (S), said plurality of reinforcing ribs each having a terminal end contiguous said imaginary screwing line (S), and at least some of said reinforcing ribs being of different axial lengths.