NOVELTY - A gas-barrier multilayer film consists of a primer layer (13) and a vapor-deposited film layer (15) of inorganic oxide, laminated sequentially on the surface(s) of a resin base material (11). The primer layer comprises a thermosetting reaction composite of amine-type hardener, and an acrylic resin containing (meth)acrylic acid derivative having an epoxy group, and (meth)acrylic acid derivative having hydroxyl group, and the hydrolysis product of a silane coupling agent. The multilayer film has a water-vapor permeability of 1 g/m2/day or less.    USE - Gas-barrier multilayer film is used for protecting target e.g. solar cells, electronic paper, LCD elements, electromagnetic wave shielding materials, touch panels, and organic electroluminescent element, from gas e.g. in-air moisture, oxygen, and carbon dioxide. Can also be used for packaging foodstuffs, pharmaceuticals, daily necessaries, and electronic devices.    ADVANTAGE - The gas-barrier multilayer film has excellent water-vapor barrier property. The vapor-deposited film layer has excellent heat resistance, moisture resistance, and water resistance. The primer layer is formed without using noxious isocyanate compound.    DETAILED DESCRIPTION - A gas-barrier multilayer film consists of a primer layer and a vapor-deposited film layer consisting of inorganic oxide, laminated sequentially on the surface(s) of a resin base material. The primer layer comprises a thermosetting reaction composite of amine-type hardener, and an acrylic resin containing (meth)acrylic acid derivative (5-50 mol%) having an epoxy group, and (meth)acrylic acid derivative (5-30 mol%) having hydroxyl group, and the hydrolysis product of a silane coupling agent of formula: Si(R1)n(OR2)3-nY'. The acrylic resin is a copolymer with styrene contained in a copolymerization ratio of 0-40 mol%. The multilayer film has a water-vapor permeability of 1 g/m2/day or less.    R1=alkyl;    R2=CH3, C2H5 or CH3OC;    Y'=epoxy group;and    n=0-2.    DESCRIPTION OF DRAWING(S) - The drawing shows a sectional view of the gas-barrier multilayer film.    Resin base material (11)    Primer layer (13)    Vapor-deposited film layer (15)    Gas-barrier coating layer (17)