Fuente: WIPO "tomato" The present invention relates to a method for manufacturing a gasbarrier coated substrate material (10a; 10b), coated with a layer of reduced graphene oxide.The invention further relates to laminated packaging materials (20a; 20b) comprising the barrier-coated substrate material (10a; 10b), in particular intended for liquid carton food packaging, and to liquid carton packaging containers comprising the laminated packaging material.