Abstract: A synthetic paper suitable for in-mould labelling is formed from a composite plastics sheet which is printable on at least one surface, and comprises a base layer and optionally a printable layer forming the printable surface. The base layer has a density of 0.65 g/cm3 or less, or, if there is no separate adhesive layer on the surface opposite the printable surface, a density of 0.7 g/cm3 or less. Preferably the base layer comprises a core layer and a co-extruded layer or layers, on one or both surfaces of the core layer. One of the co-extruded layers is preferably heat-sealable to blow-moulded bottles or other articles, and may comprise low density polyethylene, ethylene vinyl acetate copolymer, ethylene methacrylic acid copolymer or ethylene acrylic acid copolymer.