BAHNFOERMIGES MATERIAL

摘要

Sheet material 10 e.g. high density P.V.C. having at least one portion provided with a required stiffness by forming said portion with corrugations. The plan view dimensions of the sheet when corrugated are substantially the same as those of the original sheet, the corrugations being formed by a machine tool having co-operating teeth 4 with an interference fit on their flanks 6 so that the sheet 10 is stretched by the peaks 7 of the teeth 4. Typically, a neck stiffener 21 for a man's shirt is formed from a strip 22 having an initial thickness of 0.2 of a millimetre with end portions 23 formed with corrugations 24 having a lateral distance of 2.7 millimetres between two adjacent peaks or troughs and a vertical distance between a peak and trough of 0.6 of a millimetre. Other articles include an inverted trunkated cone or hollow cylinder corrugated for use as a pot plant protector and a corrugated separator for layers of chocolates in a box. <IMAGE>