a flexible film laminate especially adapted for use in the manufacture of a retortable pouch for the packaging of food is disclosed which comprises : a first layer of heat - sealable polyolefin ; a second layer of previously metallized thermoplastic polymer bonded to said first layer ; and , an adhesive bonding the first layer to the metallized surface of the second layer , said adhesive being a maleic acid anhydride adduct of ethylene - propylene copolymer .