Abstract: The invention relates to a two-layer composite material comprising a metal foil and an adhesive layer.The adhesive layer is formed of a mixture of two compounds A and B, compound A being a copolymer of an aliphatic monoolefin and a monoethylenically unsaturated carboxylic acid which has good adhesion for the metal foil and the container, and compound B being a compound adapted to reduce the adhesion of compound A for the metal foil and/or the container.Said composite material is intended in particular for the fabrication of caps serving as closures for containers.