| 摘要 |
<p>Composite material for plastic caps, especially screw caps (screw-tops), providing both sealing against liquids and impermeability to gases, characterised in that it comprises, joined together into a coherent multilayer structure, at least one central layer (4) made of a plastic having a gas-barrier effect and a high modulus of rigidity, two outer layers (7) placed on either side of the central layer and consisting of a plastic having a low modulus of rigidity, the outer layers each having a thickness greater than the thickness of the central layer, and between the central layer (4) and each outer layer (7), an interlayer (5) made of a material of the same family as the outer layer, but with a high modulus of rigidity. <IMAGE></p> |
