Japan Crown Cork Co Ltd.

Hiroyuki Oda

Junichi Itsubo

Fumio Mori

Gunji Matsuda

A plastic closure having pilfer-proofing characteristics for a container including a mouth-neck portion having formed on its peripheral surface an external thread and an annular flange located beneath it. The closure includes a top panel wall and a cylindrical skirt wall extending downwardly from the peripheral edge of the top panel wall. A breakable line extending circumferentially is formed on the skirt wall to divide the skirt wall into a main portion above the breakable line and a pilfer-proof bottom portion below it, and an internal thread adapted to be fitted with the external thread of the mouth-neck portion of the container is formed on the inner surface of the main portion of the skirt wall. The inner surface of the pilfer-proof bottom portion has formed therein at least one flap extending radially inwardly therefrom.

Plastic closure for containers

Disclosed is a bottle for a carbonated drink, which is formed by biaxial draw-blow molding of a polyester containing a surface active agent and being composed mainly of ethylene terephthalate units, wherein at least the barrel wall portion of the bottle is molecularly oriented biaxially so that the density is at least 1.34 g/cm.sup.3 as measured at 20.degree. C., and the surface active agent is distributed in the surface of the barrel wall portion so that the contact angle of the surface of the barrel wall portion to water is not larger than 76.degree.. In this bottle, the speed of transfer of carbon dioxide gas from the liquid phase of the drink to the gas phase at the time of opening the bottle is controlled to a very low level. Accordingly, occurrence of the cap missile phenomenon at the time of removing the cap from the bottle or reduction of the carbon dioxide content in the drink at the time of repeating sealing and opening of the bottle can effectively be prevented.

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Hiratsuka, Japan

Hiroyuki Oda