NOVELTY - A cured organopolysiloxane resin film having gas barrier properties where layer of cured organopolysiloxane contains organic functional group, organic groups (G1) or hydrosilyl/silanol group, is formed on a visible region-transparent film comprising cured organopolysiloxane resin (OP1) obtained by crosslinking (A) organopolysiloxane resin and (B) organosilicon compound in the presence of (C) hydrosilylation reaction catalyst, and a transparent inorganic layer (L1) selected from silicon oxynitride, silicon nitride and silicon oxide layers is formed on cured organopolysiloxane layer.    USE - As a film substrate for the transparent electrodes in electroluminescent displays and liquid-crystal displays; as a back sheet for crystalline silicon solar cells; and as a substrate for amorphous silicon solar cells.    ADVANTAGE - The cured organopolysiloxane resin film that exhibits, inter alia, excellent gas barrier properties. The cured organopolysiloxane resin film, is free-standing film that is transparent in the visible region and exhibits an excellent heat resistance and that exhibits a high gas barrier performance due to an excellent adherence by a uniformly formed transparent inorganic layer, that is, transparent inorganic film selected from silicon oxynitride layer, that is, silicon oxynitride film, silicon nitride layer, that is, silicon nitride film, and silicon oxide layer, that is, silicon oxide film, to the cured organopolysiloxane resin film, particularly free-standing film. The cured organopolysiloxane resin film, particularly free-standing film having gas barrier properties exhibits an excellent durability and an excellent capacity to block a variety of gases, such as air, steam, nitrogen gas, oxygen gas, carbon dioxide gas and argon gas. The methods of producing the cured organopolysiloxane resin film, provide the cured organopolysiloxane resin film, particularly free-standing film easily and surely.    DETAILED DESCRIPTION - A cured organopolysiloxane resin film having gas barrier properties, where layer of cured organopolysiloxane contains an organic functional group, an organic groups (G1) produced by polymerization between polymerizable organic functional groups or a hydrosilyl or silanol group, is formed on a film which is transparent in the visible region and comprising a cured organopolysiloxane resin (OP1) obtained by a crosslinking reaction between (A) an organopolysiloxane resin that is represented by the average siloxane unit of formula R'aSiO(4-a)/2 (I) and that has an average of at least 1.2 2-10C unsaturated aliphatic hydrocarbyls per molecule; and (B) an organosilicon compound having at least two silicon-bonded hydrogen atoms per molecule in the presence of (C) a hydrosilylation reaction catalyst, and a transparent inorganic layer (L1) selected from silicon oxynitride layer, silicon nitride layer, and silicon oxide layer is formed on the cured organopolysiloxane layer.    R'=1-10C monovalent hydrocarbyl;and    a=greater that 0.5 and less than 2.    INDEPENDENT CLAIMS are included for the following:    (1) producing (M1) the cured organopolysiloxane resin film, where layer of cured organopolysiloxane contains organic functional group, involving: coating and curing an organic functional group-containing curable organosilane or its composition or an organic functional group-containing curable organopolysiloxane or its composition on a film which is transparent in the visible region and comprising resin (OP1), to form on the film an organic functional group-containing cured organopolysiloxane layer; and then forming, by vapor deposition, the layer (L1), on the cured organopolysiloxane layer;    (2) producing (M2) the cured organopolysiloxane resin film, where layer of cured organopolysiloxane contains organic groups (G1), involving either coating an organopolysiloxane that has polymerizable organic functional groups on film which is transparent in the visible region and comprising resin (OP1); crosslinking the organopolysiloxane by polymerization of the polymerizable organic functional groups with each other to form a layer of cured organopolysiloxane having organic groups on the film; and then forming, by vapor deposition, the layer (L1), on the cured organopolysiloxane layer; or coating a polymerizable organic functional group- and crosslinking group-containing curable organopolysiloxane or its composition on a film which is transparent in the visible region and comprising resin (OP1); reacting the crosslinking groups with each other and polymerizing the polymerizable organic functional groups with each other to form a layer of cured organopolysiloxane having organic groups on the film; and then forming, by vapor deposition, the layer (L1), on the cured organopolysiloxane layer;    (3) producing (M3) the cured organopolysiloxane resin film, where layer of cured organopolysiloxane contains hydrosilyl or silanol group, involving either coating and curing a hydrosilylation reaction-curable organopolysiloxane composition comprising (a1) organopolysiloxane that has at least two alkenyl groups per molecule, (b1) an organosilicon compound that has at least two silicon-bonded hydrogen atoms per molecule, and (c1) hydrosilylation reaction catalyst where the molar ratio between the hydrosilyl groups in component (b1) and the alkenyl groups in component (a1) is at least 1.05, on a film which is transparent in the visible region and comprising resin (OP1), to form a hydrosilyl group-containing cured organopolysiloxane layer on the film; and forming, by vapor deposition, the layer (L1), on the cured organopolysiloxane layer; or coating and curing a condensation reaction-curable organosilane, condensation reaction-curable organosilane composition, condensation reaction-curable organopolysiloxane, or condensation reaction-curable organopolysiloxane composition on a film which is transparent in the visible region and comprising resin (OP1), to form silanol group-containing cured organopolysiloxane layer on the film; and forming, by vapor deposition, the layer (L1), on the cured organopolysiloxane layer; and    (4) producing a cured organopolysiloxane resin film having gas barrier properties, involving forming a silicon oxynitride layer by a reactive ion plating procedure on a hydrosilyl group-containing cured organopolysiloxane resin film which is transparent in the visible region and is obtained by crosslinking (A) and (B) (where the molar ratio between the hydrosilyl groups in component (B) and the unsaturated aliphatic hydrocarbyl in component (A) is 1.05-1.50) in the presence of (C).