A liquid ink, drop-on-demand pagewidth printhead including a semiconductor substrate, a plurality of drop-emitter nozzles fabricated on the substrate; an ink supply manifold coupled to the nozzles; pressure element for subjecting ink in the manifold to a pressure above ambient pressure; a drop...http://www.google.com/patents/US5726693?utm_source=gb-gplus-sharePatent US5726693 - Ink printing apparatus using ink surfactants
