摘要 |
The invention relates to a method for producing a hollow article of polymeric materials. The hollow article is produced by means of extrusion and comprises a multilayered, tubular preform having at least one foamable wall. Immediately after its forming, in the still thermoplastic state, the preform is enclosed by a dividable mould in a seal-tight manner in the parting region, is expanded in its foamable wall, brought into the final shape and, after cooling, removed from the mould as a hollow body. According to the invention, the preform is brought to bear here against the contours of the mould by means of a vacuum, which acts on its surface areas lying free in the mould cavity. |