Electrodeposition of paint (EDP) has been investigated with the aid of electrochemical methods using four various binders pigmented with five various carbon blacks (c.b.) in the concentration range of 0–25 weight percent (w/o) (in the solid). Electrodeposition itself is not influenced at low to medium c.b. concentrations, where ionic wet film resistivity is even slightly enhanced by single particles dispersed in the binder. At a relatively high critical c.b. concentration , where strong electronic conductivity in the wet film is initiated due to the formation of linear agglomerates of c.b. particles, heavily deteriorated deposits are produced with warts at the surface. In the stoved film, electronic conductivities are in the range of 10−9–10−5 S cm−1. Percolation sets in at extremely low c.b. concentrations in the order of 1 w/o. This is rationalized by a model of transversal c.b. chains, where electrons are tunneling through ultrathin dielectric films between the c.b. particles. The electrodeposition of a second homogeneous layer on top of the stoved film becomes possible above a critical c.b. concentration in the order of 5 w/o. This can be interpreted as the consequence of isolated surface point contacts at lower c.b. concentrations. Rapid spherical off‐diffusion of precipitating ions prevent the establishment of the critical surface concentration for electrocoagulation. At higher c.b. concentrations, the point contacts are amalgamated, and slow linear diffusion is achieved. Practical conclusions are drawn at the end of the report.