Process for treating a membrane for vulcanisation apparatuses for vulcanising and moulding tyres, wherein the apparatus comprises: a vulcanisation mould internally delimiting a vulcanisation and moulding cavity having a shape corresponding to an external shape to be conferred to a tyre once moulded and vulcanised; devices operatively associated with the vulcanisation and moulding cavity and configured for administering heat to the tyre contained in said vulcanisation and moulding cavity so as to vulcanise said tyre; a membrane arranged in the vulcanisation and moulding cavity; wherein the membrane is movable at least between a contracted configuration and an expanded configuration; wherein in the contracted configuration, an external surface of the membrane is spaced from a radially inner surface of the tyre and wherein portions of an internal surface of the membrane, opposite the external surface, lie in mutual contact and/or in contact with elements of said apparatus; wherein in the expanded configuration, the external surface of the membrane is engaged and presses against the radially inner surface of the tyre; wherein the process comprises: - preparing the membrane comprising the external surface and the internal surface opposite the external surface; - applying at least one internal protective layer on the internal surface; characterized in that applying said at least one internal protective layer comprises applying at least two internal protective layers that are mutually superimposed by preparing a substantially crosslinkable composition and: a) covering the internal surface with said substantially crosslinkable composition; b) crosslinking said substantially crosslinkable composition on the internal surface; c) repeating the operations a) and b) at least once. a vulcanisation mould internally delimiting a vulcanisation and moulding cavity having a shape corresponding to an external shape to be conferred to a tyre once moulded and vulcanised; devices operatively associated with the vulcanisation and moulding cavity and configured for administering heat to the tyre contained in said vulcanisation and moulding cavity so as to vulcanise said tyre; a membrane arranged in the vulcanisation and moulding cavity; wherein the membrane is movable at least between a contracted configuration and an expanded configuration; wherein in the contracted configuration, an external surface of the membrane is spaced from a radially inner surface of the tyre and wherein portions of an internal surface of the membrane, opposite the external surface, lie in mutual contact and/or in contact with elements of said apparatus; wherein in the expanded configuration, the external surface of the membrane is engaged and presses against the radially inner surface of the tyre; - preparing the membrane comprising the external surface and the internal surface opposite the external surface; - applying at least one internal protective layer on the internal surface; a) covering the internal surface with said substantially crosslinkable composition; b) crosslinking said substantially crosslinkable composition on the internal surface; c) repeating the operations a) and b) at least once.