Fuente: WIPO "tomato" There is described a multilayer structure (14) comprising: a substrate (15) made of transparent material; a coating (16) comprising functional carbonylic groups, wherein coating (16) is obtained by applying plasma treatment to substrate (15) There is also described a packaging machine (1) for producing sealed packages (2) containing a pourable product, the packaging machine (1) comprises at least one lighting device (10) and/or at least one protective case (17) and/or at least one protective wall (21) provided with the multilayer structure (14).