A solvent-free electroconductive composition may be used to make electroconductive lines on a surface of a substrate or electroconductive plugs within via holes of a substrate. The solvent-free electroconductive composition is generally made of about 40 to about 95 wt % of a conductive component, about 4 to about 30 wt % of a polymer or oligomer comprising a reactive functional group, up to about 20 wt % of a monomeric diluent comprising a reactive functional group, and up to about 3 wt % of a curing agent. In some instances, the solvent-free electroconductive composition further includes up to about 3 wt % of a lubricating compound. Substrates made using solvent-free electroconductive compositions may be used in printed circuit boards, integrated circuits, solar cells, capacitors, resistors, thermistors, varistors, resonators, transducers, inductors, and multilayer ferrite beads.