摘要 |
A one-piece plastics closure for a carbonated beverage bottle has a sealing ring (24) which extends inwardly and downardly towards the closure mouth from its attachment to the closure body. When the closure is fitted the ring extends around the outer radius (56) and over the annular top face (50) of the bottle neck, backed by a stepless abutment and reaction surface (34) of the closure body. The latter surface engages the sealing ring mechanically above the container top face (50) to determine the fitted position of the closure and create a seal when the pressure in the bottle is low. When the product pressure is high, however, the effective seal is made between the sealing ring (24) and the outer radius (56) of the bottle neck. For that purpose the abutment and reaction surface is roughened, so allowing access for the product pressure to the back of the sealing ring. <IMAGE> |