Method for the production of composite containers

The method of making an article having a first wall including an arcuate edge portion and a second wall folded relative to the first wall from the arcuate edge portion of said first wall comprising forming a flat blank having first and second panels conforming to the respective first and second walls with the arc of the arcuate edge portion of said first panel intersecting the adjacent edge of said second panel at two spaced positions, forming a slit in the blank between said spaced positions to define a pair of hinge parts at the ends of the slit adjacent the points of intersection of said panels and also to define a cut-away in at least one of the panels when the panels are folded relative to one another about said hinge parts to the relative panel positions required by the shape of the article, folding said panels to said relative positions, confining the so folded panels between two mould tools which define a blank cavity for receiving the panels in their relative folded positions and also define a mould cavity in the region of the cut-away and in the region of edges of the panels juxtaposed by virtue of folding said panels to their relative positions, and injecting material into the mould cavity to complete that panel having the cut-away formed by said slit and to connect said juxtaposed edges.