Closure with cured expanded plastisol liner - engaging under container neck ridge with locking bead formed solely by expansion

摘要

A closure comprises a shell (22) with a liner (24) having a lower radially inward locking bead formed solely due to expansion and engaging below a container neck finish bead (20). The shell pref. has a cylindrical upper part and is radially outwardly enlarged at the bead where the liner thickness is greater than in axially adjacent parts. The liner pref. terminates below the bead in a tapered ramp ending at the shell intermediate ends of the shell enlargement. The plastisol pref. has an expansion rate which increases with thickness and expands when cured so that thickened areas increase in thickness to a greater linear extent than thinner areas. The uncured liner may be contoured by a moulding punch and may have a skirt interior surface which is a straight line in cross-section.