Silver nanocluster-silica composite antibacterial coatings for materials to be used in mobile telephones

Antibacterial coatings containing different amount of metallic silver nanoclusters embedded in a silica matrix have been deposited by co-sputtering technique on several different polymers used in mobile telephones components such as: screens, covers, and microphone felts. Sputtering parameters have been varied to obtain different coating thickness and silver content, in order to meet antibacterial, aesthetic and functional requirements for each component. In particular, an antibacterial functionality has been obtained for screens, covers and felts without affecting their respective transparency, aesthetic and acoustic properties. The optimal parameters for each part have been used to obtain an antibacterial mobile telephone suitable for personnel operating in hospitals or other environments with potentially high bacterial contamination.