| 摘要 |
<p>A composite stopper (1) made of synthetic materials, particularly for bottles and similar containers, comprises a substantially cylindrical central body (2) made of thermoplastic material and defining a longitudinal axis (L), with a side surface (3) and two substantially flat end faces (4, 4'), and at least two elastic rings (5, 6) located in corresponding annular seats (7, 7') on the side surface (3). The two elastic rings (5, 6) are made of plastic materials which are different from each other and from the base material of the central body (2). The base materials of the elastic rings (5, 6) are non-toxic, in particular at least one of them being made of nitrile rubber having a formulation able to ensure optimum gas impermeability, and at least the other one being made of silicone rubber having a formulation able to ensure complete compatibility for alimentary use and a high resistance to ageing.</p> |
