Gas barrier film, laminate, and packaging material

A laminate comprising:

• a gas barrier film including,
• a base material that is an unstretched film, and containing a polyethylene as a main resin component of the base material, and
• an inorganic oxide layer on a first surface side of the base material, and
• a heat seal layer that is an unstretched film, the heat seal layer containing a polyethylene as a main resin component of the heat seal layer and being joined to the gas barrier film by an epoxy-based gas barrier adhesive layer on the inorganic oxide layer such that the inorganic oxide layer and the epoxy-based gas barrier adhesive layer are sandwiched between the base material and the heat seal layer without an overcoat layer between the base material and the heat seal layer,
• wherein the base material has both;
• (i) a crystallinity on the first surface side of less than 30%, and
• (ii) a density in a range from 0.940 g/cm3 to 0.952 g/cm3,
• a proportion of the polyethylene in an entirety of the gas barrier film is 90 mass % or more,
• the laminate is without an oxygen barrier membrane containing water-swellable mica, and
• a thickness of the epoxy-based gas barrier adhesive layer is within a range of 1 to 5 μm, and the thickness of the epoxy-based gas barrier adhesive layer is 50 times or more and 300 times or less than a thickness of the inorganic oxide layer.