Patent ID: 7556720

Claim:
Method for the metallization of a plastic tank with at least one opening, comprising the steps of: preparing a chamber for vacuum processes; introducing said plastic tank into said chamber, the plastic tank being provided with a loading pipe union and an unloading pipe union; creating a pre-vacuum in said chamber; subjecting the gas inside said chamber to an electric field such that it generates a plasma suitable for forming, on the outer surface of said tank, a modified surface layer with an improved wettability; creating a high-vacuum in said chamber; depositing a layer of conductive metallic material superposing said surface layer of the tank to obtain a tank metallized on the outside by using vacuum PVD (physical Vapor Deposition) technique, and re-establishing atmospheric pressure in said chamber, wherein at least one of the pipe unions is closed through means suitable for allowing the passage of gas and for preventing the passage of metallic molecules during the step of depositing a layer of conductive metallic material.