A container and preferably a thermoplastic container, is disclosed which offers an improved structure around the container top opening to allow better sealing of a crimped-on closure member.

Liquified and compressed gases are sold in cylinders having threaded necks which attach to lanterns, stoves, torches, etc., which use the gas as fuel. A tearable plastic cap fits over the neck and has an internal bead which snaps under a shoulder on the neck. Above the shoulder is a circumferential first score line and a second score line extends to the bottom of the cap. In proximity to the second score line is a pull tab. Before the tab is pulled, the cap prevents surreptitious dispensing of the gas, protects the threads and prevents contamination of the neck and of the valve inside the neck. To remove the cap, the tab is pulled, tearing the cap along the second and then the first score line, thereby removing the lower portion of the cap, including the bead. The upper portion of the cap may be used for reclosure.

A plastic cap has a tearable outer skirt depending from a top disc, the interior of the skirt having means engaging with cooperating means on a container neck to hold the cap in place until the lower portion of the skirt is torn. To prevent dishonest persons from defeating the tamper resistant character of the cap by prying upward on the bottom edge of the cap skirt, a shoulder has been formed on the neck fitting closely under the bottom edge of the cap skirt. To further reduce such prying, a series of protrusions is formed on the shoulder with spaces between the protrusions. The protrusions inhibit fingernails from access to the lower edge of the skirt. The bumper ring which cooperates with loading grippers is interrupted by straight sections which prevent collapse of the bumper ring when the cap is applied.

A snap-on, tamper evident plastic cap for a plastic bottle neck has a skirt with upper and lower internal locking beads which lock under extenral beads on the neck. The cap is not removable so long as the skirt is intact. The lower end of the skirt, including the lower bead, may be torn off to permit the cap to be removed. To facilitate removal, the cap skirt is formed with a score line which slants upward from the lower edge of the skirt to merge with a circumferential score line which terminates near the origin of the slanted score line. A third score line extends from the terminus of the circumferential score line down to the lower edge of the skirt. Thus there is a tab (a remnant of the original skirt) between the first and third score lines which functions as a lift tab.

A push on cap for engaging a container neck is formed with inturned thickened flanges on its inner surface which cooperate with matching grooves in the container neck to retain the cap in place when the skirt is intact. A circumferential groove is formed in the skirt intermediate the inturned thickened flanges joined with a second groove extending to the bottom edge of the skirt. A tab projecting beyond the skirt is gripped and pulled causing the skirt to tear upward and then circumferentially thereby removing the lower thickened flange and permitting the top of the cap to be removed and reclosed. A rigid circumferential flange on the exterior of the skirt is spaced above the level of the uppermost inturned thickened flange and below the top of the cap has an angled gusset below the flange to prevent removing the cap by prying upwards with a fingernail prior to removing the tear skirt. The addition of the rigid circular flange and gusset and the uppermost thickened flange do not restrict the cap from expanding when pressed over the neck of the container due to the thin wall formation of the circumferential skirt of the cap.