a thermographic element containing : a substrate ; an image - forming layer coated onto the substrate ; and overlaying the image - forming layer , a topcoat layer composed of the reaction product of a polymer composed of interpolymerized units derived from : about 45 - 65 wt % of vinyl - substituted aromatic monomer ; about 15 - 30 wt % vinyl monomer containing a pendant nitrile group ; about 5 - 30 wt % hydroxyl - containing ; ethylenically - unsaturated monomer ; and a suitable crosslinking agent . a slip agent is optionally used . the topcoat layer provides a thermographic element with high gloss in the imaged areas ; has excellent runnability with no chatter in the feed direction of the element ; and exhibits no removal of topcoat which prevents formation of printhead - created voids in the imaged areas .