Printable release coatings and stamp constructions

This invention is directed to ink-imprintable or ink-receptive release coating compositions and to ink-cancelable self-adhesive postage stamps. Ink-imprintable compositions comprise a reaction product of a mixed emulsion containing a carboxylic acid terminated polydimethylsiloxane, or an isocyanate terminated polydimethylsiloxane, a hydrophilic isocyanate reactive agent, a polyisocyanate, and at least one dihydroxy terminated oligomer. Ink-imprintable stamp constructions also comprise a plurality of contiguous stamps in a roll or stacked sheet configuration without an independent release liner wherein the stamps have a pressure-sensitive adhesive on the back surface of the stamps and the above ink-imprintable release coating on the face surface of the stamps.