NOVELTY - An armouring material (1) for an air secondary battery, comprises an armouring sheet (2) constituted by laminating an outer layer including heat-resistant resin film, a metal foil layer, and an inner layer including a thermoplastic resin film, being equipped with an opening part (12) for taking oxygen in, perforating through the outer layer, the metal foil layer and the inner layer, and an oxygen-permeable membrane (3) being joined to the inner layer side in the opening part periphery (12a) so as to cover the opening part.    USE - For air secondary battery (claimed).    ADVANTAGE - The armouring material shows improved oxygen-permeablity and barrier performance against water, improved the joining strength between the inner layer of the armouring sheet and the oxygen-permeable membrane to heighten the sealing property; and provides air secondary battery which is capable of preventing leaking out of electrolyte and invading of water.    DETAILED DESCRIPTION - An armouring material (1) for an air secondary battery, comprises an armouring sheet (2) constituted by laminating an outer layer including heat-resistant resin film, a metal foil layer, and an inner layer including a thermoplastic resin film, being equipped with an opening part (12) for taking oxygen in, perforating through the outer layer, the metal foil layer and the inner layer, and an oxygen-permeable membrane (3) being joined to the inner layer side in the opening part periphery so as to cover the opening part, where the oxygen-permeable membrane is constituted from a porous fluororesin in which fluorine type resin particles are aggregated, where the joining surface of outer periphery of the oxygen-permeable membrane is equipped with a primer layer, and an adhesive layer is provided at least in the space between the primer layer and the inner layer of the armouring sheet, to adhering the oxygen-permeable membrane to the armouring sheet. INDEPENDENT CLAIMS are included for the following:    (1) an air secondary battery comprising the armouring material; and    (2) a process of producing the armouring material, involving: forming the armouring sheet constituted by laminating an outer layer including heat-resistant resin film, a metal foil layer, and an inner layer including a thermoplastic resin film, being equipped with an opening part for taking oxygen in, perforating through the outer layer, the metal foil layer and the inner layer; conducting a primer treatment on the oxygen-permeable membrane which is constituted from a porous fluororesin in which fluorine type resin particles are aggregated, to forming a primer layer on the outer periphery of the oxygen-permeable membrane; applying an adhesive to at least the joining surface in the vicinity of the opening in the surface at the side of inner surface of the armouring sheet to form an adhesive layer; and joining the oxygen-permeable membrane to the circumference of the opening of the armouring sheet by the adhesive layer.    DESCRIPTION OF DRAWING(S) - The figure shows a perspective view of an armouring material.    Armouring material (1)    Armouring sheet (2)    Oxygen-permeable membrane (3)    Opening part (12)    Periphery (12a)