Functional film manufacturing method and functional film

A functional film manufacturing method for manufacturing a functional film having a support, and two or more organic layers and one or more inorganic layers alternately formed on the support, the method comprising:

• a step of forming an organic layer by a coating process and a step of forming an inorganic layer of a silicon compound by a vapor-phase deposition process, and upon formation of an organic layer overlying an inorganic layer, further comprising a step of exposing an surface of the inorganic layer to air prior to the formation of the organic layer,
• wherein the organic layer overlying the inorganic layer is formed using a coating material containing an organic solvent, an organic compound for forming the organic layer, and a silane coupling agent in an amount of 0.1 to 25 wt % in terms of concentration in the coating material exclusive of the organic solvent and containing no pH adjuster by applying the coating material onto the surface of the inorganic layer and subjecting the coating material on the inorganic layer to heating treatment and drying at a higher temperature than an azeotropic point of a by-product due to the silane coupling agent and the organic solvent or at a higher temperature than a higher one of boiling points of the by-product and the organic solvent, then curing the organic compound.