Interrupted threads on a plastic bottle finish

摘要

This relates to a container having a neck finish which is provided with threads for receiving a closure and wherein the threads are blow molded in the formation of the container from a tubular parison. It has been found that in the blow molding of the threads, there is a thinning of the wall of the neck finish at the roots of the threads and under certain circumstances, when a closure is applied at a high torque, there is an axial collapse of the neck finish rendering the container unfit for use. The problem of axial collapse of the neck finish is overcome by interrupting the threads so as to provide axial beam strength at circumferential intervals around the neck finish.