Abstract: An apparatus for the cutting and creasing of plastics material sheet is disclosed which comprises a cutting and creasing tool and a corresponding plate arranged for mutual contact characterized in that the plate is free of raised surfaces and is covered with a plastic material, preferably nylon. Additionally, an apparatus for preheating corrugated plastics sheet material is described which comprises a flat bed portion adapted to receive a stack of precut corrugated sheet material blanks with their direction of corrugation aligned, heating means at at least one end of the stack, and fan means at at least one end of the stack, the heating and fan means being arranged such as to direct heated air along the corrugation of at least some of the sheets in the stack and back via the remainder of the sheets in the stack in an endless loop.

Abstract: A box with integral corner reinforcements and a method of making the same is described. The method comprises folding the box from a prescored sheet of material so as to leave a flap adjacent each corner. The flap is prescored and is pushed towards its hinged corner whereby it buckles into a curved shape. The end of the flap is secured by gluing or stapling so as to stabilize the curved shape. The curved shape considerably increases the stiffness and crush resistance of the whole box and may allow may more boxes to be stacked.

Abstract: A plastic sheet material comprising a pair of opposed faces between which run a series of elongate voids, the voids being arranged such that there are a series of uninterrupted interconnections between the two opposite faces. The voids are of a cross-sectional shape such that there is a substantial absence of sharp corners. Where the voids are not in themselves round, the corners are radiussed. In a preferred construction, two series of interconnections are provided which join one another where they meet. The construction is particularly useful in packaging, especially the packaging of food products. The present invention has high buckling resistance in both the machine and cross-machine directions and is particularly resistant to torsional stresses, compression and/or extension and demonstrates good impact resistance.