NOVELTY - Preparing dispersion comprising complexes of polythiophene and a surfactant, comprises oxidatively polymerizing thiophene monomers in an aqueous phase in presence of a surfactant using an organic peroxide.    USE - The dispersion is useful for antistatic coating, and for producing a conductive layer in a capacitor, which is a solid electrolytic layer or a polymeric outer layer applied on a solid electrolyte layer; a hole injection layer in an organic light-emitting diode or an organic photovoltaic device; or an infrared reflective layer (all claimed).    ADVANTAGE - The dispersion exhibits improved storage stability compared to conventional dispersions. The method ensures very low increase in viscosity of the dispersion during gradual drying of the dispersion.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for:    (1) the dispersion obtainable by the above method, exhibiting a viscosity of not greater than 3 mPas, when the dispersion is adjusted to a solids content of 2-5 wt.%, an integral of the viscosity of the dispersion, which is represented as a function of the solids content, in an integration area of 0.5-5 wt.% solids, of less than 15 mPasx %, where the viscosity is determined using a rheometer in mPas at 20 degrees C, a shear rate of 100 s-1 and at a solids content in percent, a sulfate content of not greater than 200 ppm, when the dispersion is adjusted to a solids content of 2 wt.%, a sodium content of not greater than 1000 ppm, when the dispersion is adjusted to a solids content of 2 wt.%, a filterability through a 0.45 mu m filter after storage of the dispersion for 7 days at 20 degrees C, of at least 50%, when the dispersion is adjusted to a solids content of 2 wt.% before filtration, and a pH of less than 5;    (2) producing an electrically conductive layer, comprising providing a substrate, applying the above dispersion on the substrate, and at least partially removing water or the organic solvent from the dispersion to form an electrically conductive layer on the substrate; and    (3) the electrically conductive layer obtainable by the above method.