| 摘要 |
<p>One-&iece thermoplastic involable screw-on top comprises an internally threaded body, and two segments each fixed at one end to the bottom of the body skirt by a hinge flap at two adjacent points. At the free end of each segment is a lug for engaging in a recess in the bottom of the skirt opposite the flaps, for heat welding or adhesion. Each segment comprises near its lug a profile which, when the top is screwed on, engages without breaking beneath a counter-ring on the neck of the receptacle. Unscrewing of the top causes fracture of the lugs which are welded or adhered, and opening of the segments which remain fixed to the body of the top by their hinge flaps.</p> |
