NOVELTY - Manufacture of composite (10) involves forming a silicone resin layer on the surface of a porous support (12) having acidic gas separation layer formed in the surface of an acidic gas separation membrane having the acidic gas separation layer, and coating a silicone coating liquid as the silicone resin layer on the surface at the side of porous membrane of the porous support using roll-to-roll system. The porous support is a support material formed by laminating a porous membrane and an auxiliary support film. The viscosity of silicone coating liquid is 100-1 million cP.    USE - Manufacture of composite used for acidic gas separation module used for selectively-separating acidic gas e.g. carbon dioxide gas from source gas for manufacture of hydrogen gas and purification of natural gas.    ADVANTAGE - The method enables manufacture of composite with suppressed seepage of silicone coating liquid into porous support, and peeling of porous membrane and auxiliary support film, due to the presence of thin silicone resin layer.    DETAILED DESCRIPTION - Manufacture of composite involves forming a silicone resin layer on the surface of a porous support having acidic gas separation layer formed in the surface of an acidic gas separation membrane having the acidic gas separation layer, and coating a silicone coating liquid as the silicone resin layer on the surface at the side of porous membrane of the porous support using roll-to-roll system. The porous support is a support material formed by laminating a porous membrane and an auxiliary support film. The conveyance speed of the porous support is 0.5-200 m/minute. The viscosity of the silicone coating liquid is 100-1 million cP. The peeling force of porous membrane and auxiliary support film is 10 mN/mm or more.    DESCRIPTION OF DRAWING(S) - The drawing shows the schematic view of composite manufacturing apparatus.    Composite (10)    Porous support (12)    Composite manufacturing apparatus (20)    Hardening device (28)    Coiling unit (30)