Extrusion-blow-molded plastic container with undercut neck and method for its production

A method for the production of a plastic container having a container body closed with a container bottom, and a container neck connected to the container body, the container neck having a pour opening, wherein an inside wall of the container neck includes at least one calibrated structuring extending over a periphery of the inside wall at least in places, wherein the calibrated structuring is limited in a direction of the container body by a material accumulation, the material accumulation being shaped as a collar that extends at least partially along the periphery of the inside wall and crosswise to a center axis of the container neck, the method comprising:

• extruding continuously or intermittently by an extrusion head in an extrusion-blow-molding method, a section of a single-layer or multi-layer plastic hose;
• introducing the section of a single-layer or multi-layer plastic hose into a mold cavity of a blow mold tool;
• inflating and cooling the section of the single-layer or multi-layer plastic hose by introducing via a calibrating blow pin that is run into the hose through an opening in the blow mold tool, a gas that is injected with overpressure into the mold cavity to form the plastic container, wherein when the calibrating blow pin is run in, plastic material is displaced from a lost section of the plastic hose, upstream from the container neck through the pour opening in the container neck, and in the inside wall of the container neck, the at least one calibrated structuring is designed in the shape of an outside contour of a calibrating section of the calibrating blow pin;
• forming the material accumulation that limits the calibrated structuring in the direction of the container body from the plastic material;
• calibrating a section of the plastic hose that corresponds to the container neck;
• and
• demolding the plastic container.