Method and device for the production of an optimized neck contour on preforms

A method for producing preforms with an improved neck geometry beneath a threaded region or a transporting ring for a simplified subsequent blow-molding process, wherein the produced preform is made of at least one thermoplastic material and has a significantly thinner wall thickness in a neck region beneath the thread than in the thread itself, and the preform is provided in order to be formed into blow-molded containers, the method comprising:

• providing at least two channels having an increased wall thickness so that when the preform is injection molded the holding pressure is maintained, despite thin-walled regions, the at least two channels being provided on a circumference of the described preform regions;
• and designing a mold for the preform so that two or three of the channels are provided over the thin-walled region with a sufficient width to ensure maintenance of pressure in the neck region so that the preform is producible by conventional injection molding technology, wherein the channels for an injection-molding solution are configured so that, in order for a holding pressure to be maintained, the plastic material in said channels does not freeze any more quickly than the plastic material in the preform neck.