Guelph, Ontario--(Newsfile Corp. - November 9, 2020) -  ZEN Graphene Solutions Ltd. (TSXV: ZEN) (OTC Pink: ZENYF) ("ZEN" or the "Company") is pleased to announce that it has signed a binding letter of intent (LOI) with Trebor Rx Corp. (Trebor), a Canadian personal protective equipment mask manufacturer with an initial production facility...