NOVELTY - The method involves forming a carbon layer on the surface of a metallic substrate, then crimping the carbon layer to the substrate. The substrate, together with the carbon layer, are then heat-processed at a temperature of 300 to 850 degrees Celsius. Slurry containing graphite powder and a binder is then applied to the surface of the substrate, after which the substrate is heat-processed to completely decompose the binder. The binder contains at least a thickener, a phenol resin, furan resin, an epoxy resin, melamine resin, a polyimide resin, and polyvinyl chloride.    USE - Manufacturing method for fuel cell separator.    ADVANTAGE - Improves the electroconductivity of a separator by the carbonization of the binder and acquiring electroconductivity while being able to make firmer relation of graphite powder and a metallic substrate. Enables formation of a carbon layer in the metallic substrate surface uniformly, thus avoiding omission of graphite powder after slurry drying. Maintains high electroconductivity in the high temperature and acidic atmosphere inside a fuel cell for extended periods of time. Improves adhesiveness and an electroconductivity by specifying a binder and a thickener to be used. Enables the formation of a carbon layer that precisely covers the metallic substrate surface using predetermined graphite powder. Improves productivity by applying slurry appropriately on the substrate surface.    DETAILED DESCRIPTION - The thickener can be carboxymethylcellulose, an agarose, alginic acid, pectin, a carrageenan, a guar gum, a xanthan gum, gellan gum, tamarind gum, a curdlan, or psyllium. The graphite powder has, as main constituents, flaky graphite powder, expanded graphite powder or thermal decomposition graphite powder, or graphite powder.    DESCRIPTION OF DRAWING(S) - The drawing shows the schematic diagram of the contact resistance measuring apparatus used in adhesive evaluation. (Drawing includes non-English language text).    Contact resistance measuring apparatus (10)    Test body (11)    Carbon cloth (12)    Copper electrode (13)