NOVELTY - A dope (24) containing solid electrolyte and a low-boiling-point organic solvent is flow-spread on a support from a spread die (81), and a spread film is formed. The spread film is stripped off from the support, and dried to obtain a solid-electrolyte film. The film is contacted with a liquid which is a poor solvent of the solid electrolyte. The vicinity of the spread film and/or stripped-off film is pressure-reduced by a pressure controller.    USE - For manufacturing solid-electrolyte films for electrode-membrane composites used in fuel cells (all claimed), such as direct methanol fuel cells, useful as energy source for mobile phones, mobile notebook personal computers, electronic still cameras, personal digital assistants, video cameras, handheld game machines, mobile servers, mobile displays, portable generators, field lighting-equipment devices, flashlights, electrically-driven bicycles, robots, household appliances, and toys, and for redox flow batteries, lithium cells, display elements, electrode chemical sensors, signal-transmission media, capacitors, electrodialysis, electrolysis, gel actuators, salt electrolysis films, and proton exchange resins.    ADVANTAGE - The method enables continuous manufacture of solid-electrolyte films having excellent quality, ionic conductivity, and mechanical strength, with improved drying rate and without requiring acid treatment process. The obtained solid-electrolyte film provides fuels cells having excellent electromotive force.    DETAILED DESCRIPTION - A dope (24) containing solid electrolyte and a low-boiling-point organic solvent is flow-spread on a support from a spread die (81), and a spread film is formed. The spread film is stripped off from the support, and dried to obtain a solid-electrolyte film. The film is contacted with a liquid which is a poor solvent of the solid electrolyte. The vicinity of the spread film and/or stripped-off film is pressure-reduced by a pressure controller. The film(s) is dried by a drier while increasing the partial pressure of the organic solvent contained in the film. INDEPENDENT CLAIMS are included for the following:    (1) manufacturing equipment (33b) of solid-electrolyte film, equipped with a spread-film forming apparatus, a film-forming apparatus, a liquid contactor, a pressure controller, a drier, and a reduced-pressure drier;    (2) solid-electrolyte film;    (3) electrode-membrane composite comprising an anode for generating a proton from the hydrogen-containing substance, a cathode for synthesizing water from the proton and a gas, and the solid-electrolyte film with one surface contacting the anode and the other contacting the cathode; and    (4) fuel cell comprising the electrode-membrane composite and a collector contacting the electrode. The collector delivers the electron of the anode and cathode.    DESCRIPTION OF DRAWING(S) - The figure shows the schematic drawing of film manufacturing equipment. (Drawing includes non-English language text)    Dope manufacturing equipment (10)    Dope (24)    Film manufacturing equipment (33b)    Tenter (64)    Spread die (81)