The present invention is directed to an improved composition and process for preparing a non-conductive substrate for electroplating. The composition comprises 0.1 to 20% by weight graphite having a mean particle size within the range of 0.05 to 50 microns; 0.01 to 10% by weight of a water soluble or dispersible binding agent for binding to the graphite particles; an effective amount of an anionic dispersing agent for dispersing the bound graphite particles; a pH within the range of 4-14; and an aqueous dispersing medium. Optionally, the composition may contain an amount of a surfactant that is effective for wetting the through hole. The resulting graphite dispersion is capable of uniformly coating the through holes in either a double-sided or multi-layer circuit board prior to electroplating. Through holes that were treated with the disclosed graphite dispersion prior to electroplating were free of visible voids after electroplating.